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1

Fisica a escala de Planck usando o principio de incerteza generalizado: efeitos nas flutuações primordiais e buracos negros  

NASA Astrophysics Data System (ADS)

Em escalas proximas à escala de Planck todas as teorias perturbativas de cordas produzem essenciamente a mesma relação de conmutação entre as coordenadas e impulsos (a chamada "álgebra deformada"), permitindo assim estudar a física resultante independentemente dos detalhes da teoria de cordas que seja considerada correta. Este resultado completamente geral, que inclui as interações gravitacionais junto com o resto dos campos pode ser considerada uma versão generalizada (GUP) do Princípio de Incerteza de Heisenberg. Aplicamos neste trabalho essas relações de conmutação para dois sistemas físicos bem definidos: buracos negros de massas próximas à massa de Planck, e flutuações quânticas em pequenas escalas antes do universo sofrer inflação. Obtemos dois resultados concretos dos efeitos do GUP : o primeiro é que o GUP impede a evaporação completa de buracos negros microscópicos na extensão do formalismo semiclássico, deixando assim remanescentes de pequena massa que já foram postulados como candidatos a matéria escura. O segundo resultado é o 'smoothing' das flutuações primordiais em pequenas escalas que levariam à produção de buracos negros primordiais após a inflação, impedindo assim a produção abundante destes últimos e predizendo abundancias atuais bem menores do que os limites disponíveis. Concluimos que, analogamente a utilização do Princípio de Incerteza de Heisenberg para estudar e determinar propriedades fundamentais das interações sem gravitação, o GUP e uma ferramenta poderosa para estudar uma ampla variedade de sistemas trans-Planckianos e predizer seu comportamento dispensando cálculos mais detalhados proprios da teoria quântica da gravitação.

Horvath, J. E.; Custódio, P. S.

2003-08-01

2

NOTA TCNICA 001 ABRIL DE 2008 Instituto Nacional de Pesquisas Espaciais INPE. Centro Regional Sul de Pesquisas Espaciais CRS Santa Maria -RS  

E-print Network

Sul de Pesquisas Espaciais ­ CRS ­ Santa Maria - RS e-mail: geodesastressul@crs.inpe.br - http://www.inpe.br/crs ­ INPE. Centro Regional Sul de Pesquisas Espaciais ­ CRS ­ Santa Maria - RS e-mail: geodesastressul@crs.inpe.br - http://www.inpe.br/crs/geodesastres/ 2 (ação gravitacional, principalmente pela Lua-Terra). No caso das

3

Instituto Nacional de Pesquisas Espaciais -Laboratrio Associado de Plasma 1 Project ELISA  

E-print Network

- Laboratório Associado de Plasma 14 Project ELISA: costs and timetable Launching06/2006 Construction of the electron beam can corroborate indirect evidences. 2. Study of electron heating by wave.0 Range(cm) Energy (MeV) protons electrons #12;Instituto Nacional de Pesquisas Espaciais - Laboratório

4

NAS parallel benchmark results  

NASA Technical Reports Server (NTRS)

The NAS (Numerical Aerodynamic Simulation) parallel benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a 'pencil and paper' fashion. The performance results of various systems using the NAS parallel benchmarks are presented. These results represent the best results that have been reported to the authors for the specific systems listed. They represent implementation efforts performed by personnel in both the NAS Applied Research Branch of NASA Ames Research Center and in other organizations.

Bailey, D. H.; Barszcz, E.; Dagum, L.; Simon, H. D.

1992-01-01

5

NAS Parallel Benchmark Results  

Microsoft Academic Search

The NAS Parallel Benchmarks have been developed at NASA Ames Research Center to studythe performance of parallel supercomputers. The eight benchmark problems are specified in a"pencil and paper" fashion. In other words, the complete details of the problem to be solved aregiven in a technical document, and except for a few restrictions, benchmarkers are free to selectthe language constructs and

Subhash Saini; David H. Bailey

1995-01-01

6

NATIONAL ALCOHOL SURVEY (NAS)  

EPA Science Inventory

National Alcohol Survey (NAS) is designed to assess the trends in drinking practices and problems in the national population, including attitudes, norms, treatment and experiences and adverse consequences. It also studies the effects of public policy on drinking practices (i.e., ...

7

The NAS parallel benchmarks  

NASA Technical Reports Server (NTRS)

A new set of benchmarks has been developed for the performance evaluation of highly parallel supercomputers in the framework of the NASA Ames Numerical Aerodynamic Simulation (NAS) Program. These consist of five 'parallel kernel' benchmarks and three 'simulated application' benchmarks. Together they mimic the computation and data movement characteristics of large-scale computational fluid dynamics applications. The principal distinguishing feature of these benchmarks is their 'pencil and paper' specification-all details of these benchmarks are specified only algorithmically. In this way many of the difficulties associated with conventional benchmarking approaches on highly parallel systems are avoided.

Bailey, D. H.; Barszcz, E.; Barton, J. T.; Carter, R. L.; Lasinski, T. A.; Browning, D. S.; Dagum, L.; Fatoohi, R. A.; Frederickson, P. O.; Schreiber, R. S.

1991-01-01

8

NAS Parallel Benchmarks Results  

NASA Technical Reports Server (NTRS)

The NAS Parallel Benchmarks (NPB) were developed in 1991 at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a pencil and paper fashion i.e. the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select the language constructs and implementation techniques best suited for a particular system. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: Cray C90, Cray T'90 and Fujitsu VPP500; (b) Highly Parallel Processors: Cray T3D, IBM SP2 and IBM SP-TN2 (Thin Nodes 2); (c) Symmetric Multiprocessing Processors: Convex Exemplar SPP1000, Cray J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL. We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention NAS future plans of NPB.

Subhash, Saini; Bailey, David H.; Lasinski, T. A. (Technical Monitor)

1995-01-01

9

Update on NAS  

NASA Astrophysics Data System (ADS)

With the approval of the governing bodies of the National Academy of Sciences (NAS), the National Academy of Engineering (NAE), and the Institute of Medicine (IOM), the first phase of a major reorganization of the National Research Council [Eos, March 16, p. 194] is well underway. As part of the reorganization—which consolidates seven existing assemblies and commissions into three commissions, two offices, and an independent board—the new Commission on Physical Sciences, Mathematics, and Resources will combine the activities of the former Assembly of Mathematical and Physical Sciences (AMPS) and the former Commission on Natural Resources (CNR).Herbert Friedman and Robert M. White, chairman of the assembly and of the commission, respectively, will cochair the new commission for 1 year. Charles K. Reed, executive director of the former assembly, is retiring but will serve as senior advisor to help establish the new commission and will serve as a member of the commission through June 1983. Raphael G. Kasper, executive secretary of the Environmental Studies Board, will be the commission's acting executive director.

10

NASA's UAS NAS Access Project  

NASA Technical Reports Server (NTRS)

The vision of the Unmanned Aircraft System (UAS) Integration in the National Airspace System (NAS) Project is "A global transportation system which allows routine access for all classes of UAS." The goal of the UAS Integration in the NAS Project is to "contribute capabilities that reduce technical barriers related to the safety and operational challenges associated with enabling routine UAS access to the NAS." This goal will be accomplished through a two-phased approach based on development of system-level integration of key concepts, technologies and/or procedures, and demonstrations of integrated capabilities in an operationally relevant environment. Phase 1 will take place the first two years of the Project and Phase 2 will take place the following three years. The Phase 1 and 2 technical objectives are: Phase 1: Developing a gap analysis between current state of the art and the Next Generation Air Transportation System (NextGen) UAS Concept of Operations . Validating the key technical areas identified by this Project . Conducting initial modeling, simulation, and flight testing activities . Completing Sub-project Phase 1 deliverables (spectrum requirements, comparative analysis of certification methodologies, etc.) and continue Phase 2 preparation (infrastructure, tools, etc.) Phase 2: Providing regulators with a methodology for developing airworthiness requirements for UAS, and data to support development of certifications standards and regulatory guidance . Providing systems-level, integrated testing of concepts and/or capabilities that address barriers to routine access to the NAS. Through simulation and flight testing, address issues including separation assurance, communications requirements, and human systems integration in operationally relevant environments. The UAS in the NAS Project will demonstrate solutions in specific technology areas, which will address operational/safety issues related to UAS access to the NAS. Since the resource allocation for this Project is limited ($150M over the five years), the focus is on reducing the technical barriers where NASA has unique capabilities. As a result, technical areas, such as Sense and Avoid (SAA) and beyond line of sight command and control will not be addressed. While these are critical barriers to UAS access, currently, there is a great deal of global effort being exercised to address these challenge areas. Instead, specific technology development in areas where there is certainty that NASA can advance the research to high technology readiness levels will be the Project's focus. Specific sub-projects include Separation Assurance, Human Systems Integration, Communications, Certification, and Integrated Test and Evaluation. Each sub-project will transfer technologies to relevant key stakeholders and decision makers through research transition teams, technology forums, or through other analogous means.

Johnson, Charles W.

2011-01-01

11

Storage : DAS / SAN / NAS Dploiement  

E-print Network

les moyens de stockage directement attachés à un serveur ou une workstation ­ Sans réseau de stockage moyens de stockage directement attachés à un serveur ou une workstation ­ Sans réseau de stockage entre · Résumé ­ Type de stockage assez basique ­ Moins cher que NAS et SAN ­ Espace de stockage accédé via le

Collette. Sébastien

12

The NAS Computational Aerosciences Archive  

NASA Technical Reports Server (NTRS)

In order to further the state-of-the-art in computational aerosciences (CAS) technology, researchers must be able to gather and understand existing work in the field. One aspect of this information gathering is studying published work available in scientific journals and conference proceedings. However, current scientific publications are very limited in the type and amount of information that they can disseminate. Information is typically restricted to text, a few images, and a bibliography list. Additional information that might be useful to the researcher, such as additional visual results, referenced papers, and datasets, are not available. New forms of electronic publication, such as the World Wide Web (WWW), limit publication size only by available disk space and data transmission bandwidth, both of which are improving rapidly. The Numerical Aerodynamic Simulation (NAS) Systems Division at NASA Ames Research Center is in the process of creating an archive of CAS information on the WWW. This archive will be based on the large amount of information produced by researchers associated with the NAS facility. The archive will contain technical summaries and reports of research performed on NAS supercomputers, visual results (images, animations, visualization system scripts), datasets, and any other supporting meta-information. This information will be available via the WWW through the NAS homepage, located at http://www.nas.nasa.gov/, fully indexed for searching. The main components of the archive are technical summaries and reports, visual results, and datasets. Technical summaries are gathered every year by researchers who have been allotted resources on NAS supercomputers. These summaries, together with supporting visual results and references, are browsable by interested researchers. Referenced papers made available by researchers can be accessed through hypertext links. Technical reports are in-depth accounts of tools and applications research projects performed by NAS staff members and collaborators. Visual results, which may be available in the form of images, animations, and/or visualization scripts, are generated by researchers with respect to a certain research project, depicting dataset features that were determined important by the investigating researcher. For example, script files for visualization systems (e.g. FAST, PLOT3D, AVS) are provided to create visualizations on the user's local workstation to elucidate the key points of the numerical study. Users can then interact with the data starting where the investigator left off. Datasets are intended to give researchers an opportunity to understand previous work, 'mine' solutions for new information (for example, have you ever read a paper thinking "I wonder what the helicity density looks like?"), compare new techniques with older results, collaborate with remote colleagues, and perform validation. Supporting meta-information associated with the research projects is also important to provide additional context for research projects. This may include information such as the software used in the simulation (e.g. grid generators, flow solvers, visualization). In addition to serving the CAS research community, the information archive will also be helpful to students, visualization system developers and researchers, and management. Students (of any age) can use the data to study fluid dynamics, compare results from different flow solvers, learn about meshing techniques, etc., leading to better informed individuals. For these users it is particularly important that visualization be integrated into dataset archives. Visualization researchers can use dataset archives to test algorithms and techniques, leading to better visualization systems, Management can use the data to figure what is really going on behind the viewgraphs. All users will benefit from fast, easy, and convenient access to CFD datasets. The CAS information archive hopes to serve as a useful resource to those interested in computational sciences. At present, only information that may be di

Miceli, Kristina D.; Globus, Al; Lasinski, T. A. (Technical Monitor)

1995-01-01

13

Mapa Geologico de Venezuela a Escala 1:750,000  

USGS Publications Warehouse

Se presenta un mapa geologico digital de Venezuela sobre un fondo de relieve sombreado. Los datos geologicos e hidrologicos del norte del rio Orinoco proceden de la digitalizacion de mapas geologicos en papel a escala 1:500.000. Estos datos fueron integrados con el mapa geologico digital del Escudo de Guayana Venezolano, a su vez derivado de hojas en papel a escala 1:500.000. La informacion sobre los tipos de fallas mostrados en el mapa es igual que en las fuentes originales. Los poligonos geologicos fueron atribuidos por edad, litologia y nombre de la unidad siguiendo el Codigo geologico de Venezuela. Se incorporaron revisiones significativas de la geologia de la Cordillera de la Costa a partir de las nuevas hojas integradas a escala 1:25.000. Toda esta informacion geologico-estructural se sobrepuso a una imagen de relieve sombreado, producida por el procesamiento de los datos de radar interferometrico con 90 m (3 arcosegundos) de resolucion espacial obtenidos por la mision topografica de radar del transbordador espacial (SRTM). Las areas de la base de datos del SRTM carentes de informacion fueron llenadas por medio de la interpolacion de los datos de las celdas adyacentes. Para producir la imagen de relieve sombreado se uso una direccion de iluminacion de 315 deg con un angulo de 65 deg sobre el horizonte. La proyeccion usada en el mapa es conica equidistante, con latitudes de 4 y 9 deg norte como paralelos estandar y una longitud de 66 deg al oeste como meridiano central. Los datos en el mapa proceden primordialment de hojas a escala 1:500.000 y el producto esta preparado para una impresion optima en escala 1:750.000. Los usuarios pueden obtener ampliaciones mayores, sin embargo no se garantiza la precision del mapa a escalas mas detalladas. Especialmente en la region de Guayana, al sobreponer los mapas geologicos sobre la reciente imagen SRTM, se notan grandes discrepancias no sistematicas tanto en contactos como en fallas. Esto es debido a que los mapas geologicos de Guayana tienen como base topografica las imagenes de radar de vision lateral (SLAR), con muy control de campo de los a?os 1970's. La correccion de estos desfases esta planificada para el futuro.

Hackley, Paul C.; Urbani, Franco; Karlsen, Alex W.; Garrity, Christopher P.

2006-01-01

14

NASA Advanced Supercomputing (NAS) User Services Group  

NASA Technical Reports Server (NTRS)

This viewgraph presentation provides an overview of NAS (NASA Advanced Supercomputing), its goals, and its mainframe computer assets. Also covered are its functions, including systems monitoring and technical support.

Pandori, John; Hamilton, Chris; Niggley, C. E.; Parks, John W. (Technical Monitor)

2002-01-01

15

The NAS Parallel Benchmark Kernels in MPL  

Microsoft Academic Search

The Numerical Aerodynamic Simulation (NAS) Parallel Benchmarks are a set ofalgorithmically specified benchmarks indicative of the computation and communicationneeds of typical large-scale aerodynamics problems. Although a greatdeal of work has been done with respect to implementing the NAS ParallelBenchmark suite on high-end vector supercomputers, multiprocessors, and multicomputers,only recently has the possibility of running such demanding applicationson workstation clusters begun to

Adam Ferrari; Adrian Filipi-martin; Soumya Viswanathan

1995-01-01

16

TITLE: The NAS Parallel Benchmarks AUTHOR: David H Bailey1  

E-print Network

TITLE: The NAS Parallel Benchmarks AUTHOR: David H Bailey1 ACRONYMS: NAS, NPB DEFINITION: The NAS Parallel Benchmarks (NPB) are a suite of parallel computer per- formance benchmarks. They were originally. Venkatakrishnan and Sisira Weeratunga. DISCUSSION: The original NAS Parallel Benchmarks consisted of eight

Bailey, David H.

17

NAS Parallel Benchmark Results D. H. Bailey L. Dagum  

E-print Network

NAS Parallel Benchmark Results D. H. Bailey L. Dagum E. Barszcz H. D. Simon NAS Applied Research 94035 Moffett Field, CA 94035 Abstract The NAS Parallel Benchmarks have been developed at NASA Ames the NAS Parallel Benchmarks. These results represent the best results that have been reported to us

Bailey, David H.

18

NAs-Ns-3034(Revm) OF TITANIUM  

E-print Network

NAs-Ns-3034(Revm) R OF TITANIUM NUCLEAR SCIENCE SERIES National Academy of Sciences of `Titanium by Vincent J. Landis San DiegoState University San Diego, California and James H. Kaye Battelle of the Inorganic Chemistryof Titanium and Analytical 11. General Reviews of the Radiochemistryof Titanium III

19

Communication Characteristics in the NAS Parallel Benchmarks  

Microsoft Academic Search

In this paper, we investigate the communication characteris- tics of the Message Passing Interface (MPI) implementation of the NAS parallel benchmarks and study the effectiveness of com- piled communication for MPI programs. Compiled communica- tion is a technique that utilizes the compiler knowledge of both the application communication requirement and the underlying network architecture to significantly optimize the performance of

Ahmad Faraj; Xin Yuan

2002-01-01

20

The NAS Parallel Benchmarks in Titanium  

E-print Network

Titanium is an explicitly parallel dialect of Java TM designed for high-performance scientific programming. It offers object-orientation, strong typing, and safe memory management in the context of a language that supports high performance and scalable parallelism. We present an overview of the language features and demonstrate their use in the context of the NAS Parallel Benchmarks, a benchmark suite of common scientific kernels. We argue that parallel languages like Titanium provide greater expressive power than conventional approaches, thereby enabling more concise and expressive code and minimizing time to solution. Moreover, the Titanium implementations of three of the NAS Parallel Benchmarks can match or even exceed the performance of the standard Fortran/MPI implementations at realistic problem sizes and processor scales, while still using far cleaner, shorter and more maintainable code.

Kaushik Datta; Kaushik Datta

21

NAS Grid Benchmarks. 1.0  

NASA Technical Reports Server (NTRS)

We provide a paper-and-pencil specification of a benchmark suite for computational grids. It is based on the NAS (NASA Advanced Supercomputing) Parallel Benchmarks (NPB) and is called the NAS Grid Benchmarks (NGB). NGB problems are presented as data flow graphs encapsulating an instance of a slightly modified NPB task in each graph node, which communicates with other nodes by sending/receiving initialization data. Like NPB, NGB specifies several different classes (problem sizes). In this report we describe classes S, W, and A, and provide verification values for each. The implementor has the freedom to choose any language, grid environment, security model, fault tolerance/error correction mechanism, etc., as long as the resulting implementation passes the verification test and reports the turnaround time of the benchmark.

VanderWijngaart, Rob; Frumkin, Michael; Biegel, Bryan A. (Technical Monitor)

2002-01-01

22

The NAS Parallel Benchmarks in Titanium  

Microsoft Academic Search

Titanium is an explicitly parallel dialect of JavaTM designed for high-performance scientific programming. It offers object-orientation, strong typing, and safe memory management in the context of a language that supports high performance and scal- able parallelism. We present an overview of the language features and demonstrate their use in the context of the NAS Parallel Benchmarks, a benchmark suite of

Kaushik Datta

2006-01-01

23

Implementation of NAS Parallel Benchmarks in Java  

NASA Technical Reports Server (NTRS)

A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would move Java closer to Fortran in the competition for CFD applications.

Frumkin, Michael; Schultz, Matthew; Jin, Hao-Qiang; Yan, Jerry

2000-01-01

24

NAS Parallel Benchmarks Results 3-95  

NASA Technical Reports Server (NTRS)

The NAS Parallel Benchmarks (NPB) were developed in 1991 at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion, i.e., the complete details of the problem are given in a NAS technical document. Except for a few restrictions, benchmark implementors are free to select the language constructs and implementation techniques best suited for a particular system. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: CRAY C90, CRAY T90 and Fujitsu VPP500; (b) Highly Parallel Processors: CRAY T3D, IBM SP2-WN (Wide Nodes), and IBM SP2-TN2 (Thin Nodes 2); and (c) Symmetric Multiprocessors: Convex Exemplar SPPIOOO, CRAY J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL (75 MHz). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention future NAS plans for the NPB.

Saini, Subhash; Bailey, David H.; Walter, Howard (Technical Monitor)

1995-01-01

25

UAS Integration in the NAS Project - Project Overview  

NASA Technical Reports Server (NTRS)

The goal of the UAS integration in the NAS Project is to contribute capabili1es that reduce technical barriers related to the safety and opera1onal challenges associated with enabling routine UAS access to the NAS.

Johnson, Chuck

2011-01-01

26

Architectural Requirements and Scalability of the NAS Parallel Benchmarks  

E-print Network

Architectural Requirements and Scalability of the NAS Parallel Benchmarks Frederick C. Wong and scalability of the NAS Parallel Benchmarks. We find that the local processor and memory systems dominate both the overall performance and scalability of the NAS parallel benchmarks, as opposed to the communication

Culler, David E.

27

Architectural Requirements and Scalability of the NAS Parallel Benchmarks  

E-print Network

Architectural Requirements and Scalability of the NAS Parallel Benchmarks Abstract We present a study of the architectural requirements and scalability of the NAS Parallel Benchmarks. We find of the benchmarks because of their all­to­all communication patterns. 1 Introduction The NAS Parallel Benchmarks

Culler, David E.

28

Architectural Requirements and Scalability of the NAS Parallel Benchmarks  

E-print Network

1 Architectural Requirements and Scalability of the NAS Parallel Benchmarks Frederick C. Wong of the NAS Parallel Benchmarks. Through direct measurements and simulations, we identify the factors which. 1 Introduction The NAS Parallel Benchmarks (NPB) are widely used to evaluate parallel machines [19

Arpaci-Dusseau, Remzi

29

HPC in Java: Experiences in Implementing the NAS Parallel Benchmarks  

E-print Network

HPC in Java: Experiences in Implementing the NAS Parallel Benchmarks BRIAN AMEDRO, DENIS CAROMEL version of the Nas Parallel Benchmarks. We first briefly describe the implementation and the performance AND COMMUNICATIONS (2010)" #12;sues. Section 5 presents the results obtained with the NAS Parallel Benchmarks on two

Boyer, Edmond

30

Architectural Requirements and Scalability of the NAS Parallel Benchmarks  

E-print Network

Architectural Requirements and Scalability of the NAS Parallel Benchmarks Frederick C. Wong and scalability of the NAS Parallel Benchmarks. We find that many complex factors affect performance. Of these Introduction The NAS Parallel Benchmarks (NPB) are widely used to evaluate parallel machines. To date, every

Culler, David E.

31

NAS Parallel Benchmarks. 2.4  

NASA Technical Reports Server (NTRS)

We describe a new problem size, called Class D, for the NAS Parallel Benchmarks (NPB), whose MPI source code implementation is being released as NPB 2.4. A brief rationale is given for how the new class is derived. We also describe the modifications made to the MPI (Message Passing Interface) implementation to allow the new class to be run on systems with 32-bit integers, and with moderate amounts of memory. Finally, we give the verification values for the new problem size.

VanderWijngaart, Rob; Biegel, Bryan A. (Technical Monitor)

2002-01-01

32

NAS Parallel Benchmarks, Multi-Zone Versions  

NASA Technical Reports Server (NTRS)

We describe an extension of the NAS Parallel Benchmarks (NPB) suite that involves solving the application benchmarks LU, BT and SP on collections of loosely coupled discretization meshes. The solutions on the meshes are updated independently, but after each time step they exchange boundary value information. This strategy, which is common among structured-mesh production flow solver codes in use at NASA Ames and elsewhere, provides relatively easily exploitable coarse-grain parallelism between meshes. Since the individual application benchmarks also allow fine-grain parallelism themselves, this NPB extension, named NPB Multi-Zone (NPB-MZ), is a good candidate for testing hybrid and multi-level parallelization tools and strategies.

vanderWijngaart, Rob F.; Haopiang, Jin

2003-01-01

33

Performance and the NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

This talk will describe the NAS (National Aerospace Standards) Parallel Benchmarks, which are now widely cited in the high performance computing field as a measure of sustained performance on realistic scientific applications. The latest performance results will be included. It will be shown that significant progress has been made by several systems during the past year or so, with sustained performance on a par with the best conventional systems, and with performance per dollar significantly exceeding the conventional systems. This talk will also describe many of the pitfalls of performance reporting, and will give advice on how to avoid such pitfalls. The overall state of the field of high performance computing will also be discussed.

Bailey, David H.; Lasinski, T. A. (Technical Monitor)

1994-01-01

34

NAS Grid Benchmarks: A Tool for Grid Space Exploration  

Microsoft Academic Search

We present a benchmark suite for computational grids in this paper. It is based on the NAS Parallel Benchmarks (NPB) and is called the NAS Grid Benchmark (NGB). We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending\\/receiving initialization data. These nodes may be

Michael A. Frumkin; Rob F. Van Der Wijngaart

2001-01-01

35

An Implementation Plan for NFS at NASA's NAS Facility  

NASA Technical Reports Server (NTRS)

This document discusses how NASA's NAS can benefit from the Sun Microsystems' Network File System (NFS). A case study is presented to demonstrate the effects of NFS on the NAS supercomputing environment. Potential problems are addressed and an implementation strategy is proposed.

Lam, Terance L.; Kutler, Paul (Technical Monitor)

1998-01-01

36

Theoretical calculations on the NaS and NaS+ radicals: electronic structure, spectroscopy and spin-orbit couplings  

NASA Astrophysics Data System (ADS)

We used an ab initio methodology for the computation of the potential energy curves of the lowest electronic states of NaS and NaS+ diatomics. Using these highly correlated wavefunctions, we calculated their spin-orbit couplings. The X2? and the A2?+ electronic states of NaS are found to possess deep potential wells. The upper bound electronic states have either shallow potential wells located in the molecular region or potentials of ~1 eV depth located for large NaS distances. For NaS+, our calculations reveal the existence of shallow potentials for all states correlating to the four lowest dissociation limits. Using our potentials, we calculated an accurate set of spectroscopic constants for NaS and NaS+. Most of the data relative to the electronic excited states represent predictions. The spin-orbit induced predissociation of NaS(A2?+ is discussed. Finally, our cationic potentials and the NaS(X2?) potential were used for the prediction of the single ionization spectrum of NaS. Tables S1-S7 are only available in electronic form at www.epj.org

Khadri, F.; Hochlaf, M.

2012-05-01

37

The NAS Parallel Benchmarks 2.1 Results  

Microsoft Academic Search

We present performance results for version 2.1 of the NAS Parallel Benchmarks(NPB) on the following architectures:ffl IBM SP2\\/66 MHzffl SGI Power Challenge Array\\/90 MHzffl Cray Research T3Dffl Intel ParagonMRJ, Inc. This work is supported through NASA Contract NAS 2-14303.yNASA Ames Research Center, Moffett Field, CA, 94035-1000.zSterling Software, Palo Alto, CA. This work is supported through NASA ContractNAS 2-13210.1Contents1 Introduction 42

William Saphir; Alex Woo; Maurice Yarrow

1996-01-01

38

UAS Integration in the NAS Project - FY 14 Annual Review  

NASA Technical Reports Server (NTRS)

This briefing gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS Projects progress and future directions.

Grindle, Laurie; Randall, Debra; Hackenberg, Davis

2014-01-01

39

Natural attenuation software (NAS): Assessing remedial strategies and estimating timeframes  

USGS Publications Warehouse

Natural Attenuation Software (NAS) is a screening tool to estimate remediation timeframes for monitored natural attenuation (MNA) and to assist in decision-making on the level of source zone treatment in conjunction with MNA using site-specific remediation objectives. Natural attenuation processes that NAS models include are advection, dispersion, sorption, non-aqueous phase liquid (NAPL) dissolution, and biodegradation of either petroleum hydrocarbons or chlorinated ethylenes. Newly-implemented enhancements to NAS designed to maximize the utility of NAS for site managers were observed. NAS has expanded source contaminant specification options to include chlorinated ethanes and chlorinated methanes, and to allow for the analysis of any other user-defined contaminants that may be subject to microbially-mediated transformations (heavy metals, radioisotopes, etc.). Included is the capability to model co-mingled plumes, with constituents from multiple contaminant categories. To enable comparison of remediation timeframe estimates between MNA and specific engineered remedial actions , NAS was modified to incorporate an estimation technique for timeframes associated with pump-and-treat remediation technology for comparison to MNA. This is an abstract of a paper presented at the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

Mendez, E.; Widdowson, M.; Chapelle, F.; Casey, C.

2005-01-01

40

NAS - Supercomputing master tool for aeronautics. [Numerical Aerodynamic Simulation  

NASA Technical Reports Server (NTRS)

Features, performance objectives and applications planned for the NASA National Aerodynamics Simulator (NAS) are outlined. NAS was conceived in the 1970s as a means to performing numerical aerodynamic simulations beyond the scope of wind tunnel testing for high-speed flight. Present supercomputers cannot deal with problems exhibiting strongly coupled viscous effects, which are being increasingly more accurately represented by approximations to the full Navier-Stokes equations. Located at the NASA-Ames Center, the NAS will by 1990 comprise a distributed computer network capable of a 4 Gflop computing rate and have a memory capacity of 1 billion 64-bit words. Remote access to the system through UNIX-based microcomputers will be available through land lines and satellite links. New supercomputers will be tested on the system without disturbing ongoing work. The core machine will be a Cray-2 with a 2 Gflop rate.

Bailey, F. R.

1985-01-01

41

Upgrades to the Probabilistic NAS Platform Air Traffic Simulation Software  

NASA Technical Reports Server (NTRS)

This document is the final report for the project entitled "Upgrades to the Probabilistic NAS Platform Air Traffic Simulation Software." This report consists of 17 sections which document the results of the several subtasks of this effort. The Probabilistic NAS Platform (PNP) is an air operations simulation platform developed and maintained by the Saab Sensis Corporation. The improvements made to the PNP simulation include the following: an airborne distributed separation assurance capability, a required time of arrival assignment and conformance capability, and a tactical and strategic weather avoidance capability.

Hunter, George; Boisvert, Benjamin

2013-01-01

42

Performance and Scalability of the NAS Parallel Benchmarks in Java  

Microsoft Academic Search

Several features make Java an attractive choice for scientific applications. In order to gauge the applicability of Java to computational fluid dynamics (CFD), we have implemented the NAS parallel benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would position Java closer to Fortran

Michael A. Frumkin; Matthew G. Schultz; Haoqiang Jin; Jerry Yan

2003-01-01

43

XcalableMP implementation and performance of NAS Parallel Benchmarks  

Microsoft Academic Search

XcalableMP is a parallel extension of existing languages, such as C and Fortran, that was proposed as a new programming model to facilitate program parallel applications for distributed memory systems. In order to investigate the performance of parallel programs written in XcalableMP, we have implemented NAS Parallel Benchmarks, specifically, the Embarrassingly Parallel (EP) benchmark, the Integer Sort (IS) benchmark, and

Masahiro Nakao; Jinpil Lee; Taisuke Boku; Mitsuhisa Sato

2010-01-01

44

Parallelization of NAS Benchmarks for Shared Memory Multiprocessore  

Microsoft Academic Search

This paper presents our experiences of parallelizing the sequential implementation of NAS benchmarks using compiler directives on SGI Origin2000 distributed shared memory (DSM) system. Porting existing applications to new high performance parallel and distributed computing platforms is a challenging task. Ideally, a user develops a sequential version of the application, leaving the task of porting the code to parallelization tools

Abdul Waheed; Jerry C. Yan

1998-01-01

45

Performance characteristics of the multi-zone NAS parallel benchmarks  

Microsoft Academic Search

We describe a new suite of computational benchmarks that models applications featuring multiple levels of parallelism. Such parallelism is often available in realistic flow computations on systems of meshes, but had not previously been captured in benchmarks. The new suite, named NPB (NAS parallel benchmarks) multi-zone, is derived from the NPB suite, and involves solving the application benchmarks LU, BT

Haoqiang Jin; Rob F. Van Der Wijngaart

2006-01-01

46

Parallelization of NAS benchmarks for shared memory multiprocessors  

Microsoft Academic Search

This paper presents our experiences of parallelizing the sequential implementation of NAS benchmarks using compiler directives on SGI Origin2000 distributed shared memory (DSM) system. Porting existing applications to new high performance parallel and distributed computing platforms is a challenging task. Ideally, a user develops a sequential version of the application, leaving the task of porting the code to parallelization tools

Abdul Waheed; Jerry Yan

1999-01-01

47

Unstructured Adaptive (UA) NAS Parallel Benchmark, Version 1.0  

Microsoft Academic Search

We present a complete specification of a new benchmark for measuring the perfor- mance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.

Huiyu Feng; Rob F. Van der Wijngaart; Rupak Biswas; Catherine Mavriplis

2004-01-01

48

Architectual Implications of the NAS MG and FT Parallel Benchmarks  

Microsoft Academic Search

This paper characterizes the structure and resource requirements of the NAS Parallel Benchmarks (NPB), a popular benchmark suite used to evaluate various parallel computers. The phase parallel model is used to obtain parameter values for memory, I\\/O, and communication latency and bandwidth requirements. These quantitative parameters are useful in the design and evaluation of various parallel computers. The results of

Yuzhong Sun; Jianyong Wang; Zhiwei Xu

1997-01-01

49

Architectural Requirements and Scalability of the NAS Parallel Benchmarks  

Microsoft Academic Search

We present a study of the architectural requirements and scalability of the NAS Parallel Benchmarks. Through direct measurements and simulations, we identify the factors which affect the scalability of benchmark codes on two relevant and distinct platforms; a cluster of workstations and a ccNUMA SGI Origin 2000. We find that the benefit of increased global cache size is pronounced in

Frederick C. Wong; Richard P. Martin; Remzi H. Arpaci-Dusseau; David E. Culler

1999-01-01

50

Performance Characteristics of the Multi-Zone NAS Parallel Benchmarks  

Microsoft Academic Search

We describe a new suite of computational benchmarks that models applications featuring multiple levels of parallelism. Such parallelism is often available in realistic flow computations on systems of grids, but had not previously been captured in bench- marks. The new suite, named NPB Multi-Zone, is extended from the NAS Parallel Benchmarks suite, and involves solving the application benchmarks LU, BT

Haoqiang Jin; Rob F. Van Der Wijngaart

2004-01-01

51

A practical study of UPC using the NAS Parallel Benchmarks  

Microsoft Academic Search

We describe a performance study of the UPC PGAS model applied to three application benchmarks from the NAS Parallel Benchmark suite. The work focuses on the performance implications of programming choices made for data affinity and data access. We compare runs of multiple versions of each benchmark encoded in UPC on both shared-memory and cluster-based parallel systems. This study points

Haoqiang Jin; Robert Hood; Piyush Mehrotra

2009-01-01

52

Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0  

NASA Technical Reports Server (NTRS)

We present a complete specification of a new benchmark for measuring the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.

Feng, Huiyu; VanderWijngaart, Rob; Biswas, Rupak; Mavriplis, Catherine

2004-01-01

53

Advanced Intermediate-Temperature Na-S Battery  

SciTech Connect

In this study, we reported an intermediate-temperature (~150°C) sodium-sulfur (Na-S) battery. With a reduced operating temperature, this novel battery can potentially reduce the cost and safety issues associated with the conventional high-temperature (300~350°C) Na-S battery. A dense ?"-Al2O3 solid membrane and tetraglyme were utilized as the electrolyte separator and catholyte solvent in this battery. Solubility tests indicated that cathode mixture of Na2S4 and S exhibited extremely high solubility in tetraglyme (e.g., > 4.1 M for Na2S4 + 4 S). CV scans of Na2S4 in tetraglyme revealed two pairs of redox couples with peaks at around 2.22 and 1.75 V, corresponding to the redox reactions of polysulfide species. The discharge/charge profiles of the Na-S battery showed a slope region and a plateau, indicating multiple steps and cell reactions. In-situ Raman measurements during battery operation suggested that polysulfide species were formed in the sequence of Na2S5 + S ? Na2S5 + Na2S4? Na2S4 + Na2S2 during discharge and in a reverse order during charge. This battery showed dramatic improvement in rate capacity and cycling stability over room-temperature Na-S batteries, which makes it attractive for renewable energy integration and other grid related applications.

Lu, Xiaochuan; Kirby, Brent W.; Xu, Wu; Li, Guosheng; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo (Gary) [Gary

2013-01-01

54

Como a Petrobras Biocombustíveis pode Engajar Agricultores de Pequena Escala Enquanto Promove a Sustentabilidade do Programa de Biodiesel Brasileiro?  

Microsoft Academic Search

A nossa pesquisa indica que a Petrobras Biocombustíveis pode ajudar a aliviar a pobreza entre os agricultores familiares de pequena escala, reforçando a integração das partes interessadas no programa brasileiro de biodiesel. Isso corrobora diversos estudos que demonstram a importância das redes compostas pelas partes interessadas (Rowley, 1997; Roloff, 2008), que podem ser particularmente importantes nos programas que visam integrar

Clovis Zapata; Diego Vazquez-Brust; José Plaza-Úbeda

2011-01-01

55

NAS Grid Benchmarks: A Tool for Grid Space Exploration  

NASA Technical Reports Server (NTRS)

We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.

Frumkin, Michael; VanderWijngaart, Rob F.; Biegel, Bryan (Technical Monitor)

2001-01-01

56

GaInNAs(Sb) Long-Wavelength VCSELs  

NASA Astrophysics Data System (ADS)

The push to provide high-speed optical network access directly to the end user is creating both significant pressure for the development of low-cost, high-speed access terminals as well as opportunities for development of entirely new technological approaches compared to those now used in the optical backbone networks. One of the most challenging is that of providing low-cost, long wavelength, single mode lasers that can be directly modulated at 10 Gbit/s, operate un-cooled in ambient environments and are easily packaged and coupled to fiber. Long wavelength vertical cavity surface emitting lasers (VCSELs) on GaAs certainly have the potential to meet these challenges. The development of MBE growth of GaInNAsSb on GaAs, issues of VCSEL design and successful demonstration of low threshold edge emitting lasers and the first 1530 nm monolithic VCSELs in GaInNAsSb on GaAs are described.

Harris, James S.; Bae, Hopil; Sarmiento, Tomás

57

New Implementations and Results for the NAS Parallel Benchmarks 2  

Microsoft Academic Search

We present new implementations and results for the NAS Parallel Benchmarks 2suite. The suite currently consists of seven programs. Of these LU, SP, BT, MG andFT have previously been released. Here we describe implementations of EP and IS, aswell as a rewritten version of FT that corrects some problems with the original release.Performance results are shown for several architectures: IBM

William Saphir; Rob F. Van Der Wijngaart; Alex Woo; Maurice Yarrow

1997-01-01

58

NAS Parallel Benchmarks I\\/O Version 2.4  

Microsoft Academic Search

We describe a benchmark problem, based on the Block-Tridiagonal (BT) prob- lem of the NAS Parallel Benchmarks (NPB), which is used to test the output capa- bilities of high-performance computing systems, especially parallel systems. We also present a source code implementation of the benchmark, called NPBIO2.4- MPI, based on the MPI implementation of NPB, using a variety of ways to

Parkson Wong; Rob F. Van der Wijngaart

2003-01-01

59

A Scalability Study of Columbia using the NAS Parallel Benchmarks  

Microsoft Academic Search

The Columbia system at the NASA Advanced Supercomputing (NAS) facility is a cluster of 20 SGI Altix nodes, each with 512 Itanium 2 processors and 1 terabyte (TB) of shared-access memory. Four of the nodes are organized as a 2048-processor capability-computing platform connected by two low-latency interconnects— NUMALink4 (NL4) and InfiniBand (IB). To evaluate the scalability of Columbia with respect

Subhash Saini; Johnny Chang; Robert Hood; Haoqiang Jin

60

THE RADIOCHEMISTRY OF IRIDIUM--NAS-NS 3045  

E-print Network

------..--------- !546.8 L472ra .c.8 THE RADIOCHEMISTRY OF IRIDIUM-- NAS-NS 3045 +- -:, G. W The Rctdiochemistry of Iridium #12;COMNll~EE ON. NUCLEAR SCIENCE L.F. CURTffS, CM~ " ROBLEY D.EVAiil%Vk8 Ckzi;c-TRY The Radiochemistry of Iridium G. W. LEDDI~ W Ridge Ndioml Lduwulwy Ckz&Ridge, T-&?See Chb3ber

61

Evaluating the Information Power Grid using the NAS Grid Benchmarks  

NASA Technical Reports Server (NTRS)

The NAS Grid Benchmarks (NGB) are a collection of synthetic distributed applications designed to rate the performance and functionality of computational grids. We compare several implementations of the NGB to determine programmability and efficiency of NASA's Information Power Grid (IPG), whose services are mostly based on the Globus Toolkit. We report on the overheads involved in porting existing NGB reference implementations to the IPG. No changes were made to the component tasks of the NGB can still be improved.

VanderWijngaartm Rob F.; Frumkin, Michael A.

2004-01-01

62

Hybrid Network Architectures for the Next Generation NAS  

NASA Technical Reports Server (NTRS)

To meet the needs of the 21st Century NAS, an integrated, network-centric infrastructure is essential that is characterized by secure, high bandwidth, digital communication systems that support precision navigation capable of reducing position errors for all aircraft to within a few meters. This system will also require precision surveillance systems capable of accurately locating all aircraft, and automatically detecting any deviations from an approved path within seconds and be able to deliver high resolution weather forecasts - critical to create 4- dimensional (space and time) profiles for up to 6 hours for all atmospheric conditions affecting aviation, including wake vortices. The 21st Century NAS will be characterized by highly accurate digital data bases depicting terrain, obstacle, and airport information no matter what visibility conditions exist. This research task will be to perform a high-level requirements analysis of the applications, information and services required by the next generation National Airspace System. The investigation and analysis is expected to lead to the development and design of several national network-centric communications architectures that would be capable of supporting the Next Generation NAS.

Madubata, Christian

2003-01-01

63

Autotasked Performance in the NAS Workload: A Statistical Analysis  

NASA Technical Reports Server (NTRS)

A statistical analysis of the workload performance of a production quality FORTRAN code for five different Cray Y-MP hardware and system software configurations is performed. The analysis was based on an experimental procedure that was designed to minimize correlations between the number of requested CPUs and the time of day the runs were initiated. Observed autotasking over heads were significantly larger for the set of jobs that requested the maximum number of CPUs. Speedups for UNICOS 6 releases show consistent wall clock speedups in the workload of around 2. which is quite good. The observed speed ups were very similar for the set of jobs that requested 8 CPUs and the set that requested 4 CPUs. The original NAS algorithm for determining charges to the user discourages autotasking in the workload. A new charging algorithm to be applied to jobs run in the NQS multitasking queues also discourages NAS users from using auto tasking. The new algorithm favors jobs requesting 8 CPUs over those that request less, although the jobs requesting 8 CPUs experienced significantly higher over head and presumably degraded system throughput. A charging algorithm is presented that has the following desirable characteristics when applied to the data: higher overhead jobs requesting 8 CPUs are penalized when compared to moderate overhead jobs requesting 4 CPUs, thereby providing a charging incentive to NAS users to use autotasking in a manner that provides them with significantly improved turnaround while also maintaining system throughput.

Carter, R. L.; Stockdale, I. E.; Kutler, Paul (Technical Monitor)

1998-01-01

64

48 CFR 852.236-82 - Payments under fixed-price construction contracts (without NAS).  

Code of Federal Regulations, 2014 CFR

...Payments under fixed-price construction contracts (without NAS). 852.236-82 ...AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses...Payments under fixed-price construction contracts (without NAS). As prescribed...

2014-10-01

65

48 CFR 852.236-83 - Payments under fixed-price construction contracts (including NAS).  

Code of Federal Regulations, 2014 CFR

...Payments under fixed-price construction contracts (including NAS). 852.236-83...AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses...Payments under fixed-price construction contracts (including NAS). As...

2014-10-01

66

Nas redes sociais, a influncia de cada um vai muito alm do que se pensava  

E-print Network

Nas redes sociais, a influência de cada um vai muito além do que se pensava Uma equipa de cientistas portugueses mostrou que, nas redes online como o Facebook ou o Twitter, a influência das opiniões Tóquio, as opiniões que estamos constantemente a proclamar perante os nossos amigos nas redes sociais

Instituto de Sistemas e Robotica

67

Performance Results for Two of the NAS Parallel Benchmarks David H. Bailey Paul O. Frederickson  

E-print Network

Performance Results for Two of the NAS Parallel Benchmarks David H. Bailey Paul O. Frederickson NAS Moffett Field, CA 94035 Abstract Two problems from the recently published "NAS Parallel Benchmarks" have been implemented on three advanced parallel computer systems. These two benchmarks are the following

Bailey, David H.

68

The Performance and Scalability of the NAS Parallel Benchmarks on a Cray SV1  

E-print Network

The Performance and Scalability of the NAS Parallel Benchmarks on a Cray SV1 Glenn R. Luecke, Ying Introduction This work investigates the performance and scalability of the eight NAS Parallel Benchmarks (NPB and the np options. The NAS Parallel Benchmarks are all written in Fortran except for the IS benchmark

Luecke, Glenn R.

69

Navigation in Grid Space with the NAS Grid Benchmarks  

NASA Technical Reports Server (NTRS)

We present a navigational tool for computational grids. The navigational process is based on measuring the grid characteristics with the NAS Grid Benchmarks (NGB) and using the measurements to assign tasks of a grid application to the grid machines. The tool allows the user to explore the grid space and to navigate the execution at a grid application to minimize its turnaround time. We introduce the notion of gridscape as a user view of the grid and show how it can be me assured by NGB, Then we demonstrate how the gridscape can be used with two different schedulers to navigate a grid application through a rudimentary grid.

Frumkin, Michael; Hood, Robert; Biegel, Bryan A. (Technical Monitor)

2002-01-01

70

High electron mobility in Ga(In)NAs films grown by molecular beam epitaxy  

SciTech Connect

We report the highest mobility values above 2000 cm{sup 2}/Vs in Si doped GaNAs film grown by molecular beam epitaxy. To understand the feature of the origin which limits the electron mobility in GaNAs, temperature dependences of mobility were measured for high mobility GaNAs and referential low mobility GaInNAs. Temperature dependent mobility for high mobility GaNAs is similar to the GaAs case, while that for low mobility GaInNAs shows large decrease in lower temperature region. The electron mobility of high quality GaNAs can be explained by intrinsic limiting factor of random alloy scattering and extrinsic factor of ionized impurity scattering.

Miyashita, Naoya; Ahsan, Nazmul; Monirul Islam, Muhammad; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Inagaki, Makoto [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan); Yamaguchi, Masafumi [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan)

2012-11-26

71

Statistical Analysis of NAS Parallel Benchmarks and LINPACK Results  

NASA Technical Reports Server (NTRS)

In the last three years extensive performance data have been reported for parallel machines both based on the NAS Parallel Benchmarks, and on LINPACK. In this study we have used the reported benchmark results and performed a number of statistical experiments using factor, cluster, and regression analyses. In addition to the performance results of LINPACK and the eight NAS parallel benchmarks, we have also included peak performance of the machine, and the LINPACK n and n(sub 1/2) values. Some of the results and observations can be summarized as follows: 1) All benchmarks are strongly correlated with peak performance. 2) LINPACK and EP have each a unique signature. 3) The remaining NPB can grouped into three groups as follows: (CG and IS), (LU and SP), and (MG, FT, and BT). Hence three (or four with EP) benchmarks are sufficient to characterize the overall NPB performance. Our poster presentation will follow a standard poster format, and will present the data of our statistical analysis in detail.

Meuer, Hans-Werner; Simon, Horst D.; Strohmeier, Erich; Lasinski, T. A. (Technical Monitor)

1994-01-01

72

Parallelization of NAS Benchmarks for Shared Memory Multiprocessors  

NASA Technical Reports Server (NTRS)

This paper presents our experiences of parallelizing the sequential implementation of NAS benchmarks using compiler directives on SGI Origin2000 distributed shared memory (DSM) system. Porting existing applications to new high performance parallel and distributed computing platforms is a challenging task. Ideally, a user develops a sequential version of the application, leaving the task of porting to new generations of high performance computing systems to parallelization tools and compilers. Due to the simplicity of programming shared-memory multiprocessors, compiler developers have provided various facilities to allow the users to exploit parallelism. Native compilers on SGI Origin2000 support multiprocessing directives to allow users to exploit loop-level parallelism in their programs. Additionally, supporting tools can accomplish this process automatically and present the results of parallelization to the users. We experimented with these compiler directives and supporting tools by parallelizing sequential implementation of NAS benchmarks. Results reported in this paper indicate that with minimal effort, the performance gain is comparable with the hand-parallelized, carefully optimized, message-passing implementations of the same benchmarks.

Waheed, Abdul; Yan, Jerry C.; Saini, Subhash (Technical Monitor)

1998-01-01

73

Thermal management of GaInNAs/GaAs VECSELs  

NASA Astrophysics Data System (ADS)

Different methods used to reduce temperature increase within the active region of vertical-external-cavity surface-emitting lasers (VECSELs) are described and compared with the aid of the self-consistent thermal finite-element method. Simulations have been carried out for the GaInNAs/GaAs multiple-quantum-well (MQW) VECSEL operating at room temperature at 1.31 ?m. Main results are presented in form of `thermal maps' which can be simply used to determine maximal temperature of different structures at specified pumping conditions. It has been found that these maps are also appropriate for some other GaAs-based VECSELs and can be very helpful especially during structure designing. Moreover, convective and thermal radiation heat transfer from laser walls has been investigated.

Sokó?, A. K.; Sarza?a, R. P.

2013-06-01

74

Identification Of Point Defects In Ga(Al)NAs Alloys  

NASA Astrophysics Data System (ADS)

By employing the optically detected magnetic resonance (ODMR) technique, two different Gai defects, namely Gai-A and Gai-B, are found and identified in the investigated Ga(Al)NAs epilayers grown on GaAs substrates by molecular-beam epitaxy (MBE). This finding shows that Ga interstitials are common intrinsic defects in various dilute nitrides. In addition to the Gai-related defects, "middle line" ODMR signals were observed at around g=2 and are suggested to arise from superposition of a defect with a single ODMR line and a defect with an unresolved HF structure. All defects studied are shown to act as non-radiative recombination centers, and are therefore harmful to performance of potential light-emitting devices based on the alloys.

Vorona, I. P.; Mchedlidze, T.; Dagnelund, D.; Buyanova, I. A.; Chen, W. M.; Köhler, K.

2007-04-01

75

Comparison of GaInNAs and GaInNAsSb solar cells grown by plasma-assisted molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

We compare dilute nitride GaInNAs and GaInNAsSb solar cells grown by molecular beam epitaxy. Single junction p-i-n diode solar cells were fabricated to test the dilute nitride and antimonide material fabrication process. Triple-junction solar cells were fabricated to test the behavior of single GaInNAs(Sb) junctions in multi-junction configuration. When nitrogen was added to the growth of GaInNAs, good crystal quality was maintained up to 4% of nitrogen at the used growth conditions. Short circuit current densities of the devices could be increased by adding Sb to the growth but at the same time the open circuit voltages decreased due to bandgap shrinkage induced by Sb. In multijunction configuration, the samples with Sb showed inferior properties to ones without it. Lower currents and voltages of Sb-containing cells may be linked to segregation of Sb and transfer to the upper junctions.

Aho, Arto; Tukiainen, Antti; Korpijärvi, Ville-Markus; Polojärvi, Ville; Salmi, Joel; Guina, Mircea

2012-10-01

76

NAS Parallel Benchmark Results 11-96. 1.0  

NASA Technical Reports Server (NTRS)

The NAS Parallel Benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion. In other words, the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select the language constructs and implementation techniques best suited for a particular system. These results represent the best results that have been reported to us by the vendors for the specific 3 systems listed. In this report, we present new NPB (Version 1.0) performance results for the following systems: DEC Alpha Server 8400 5/440, Fujitsu VPP Series (VX, VPP300, and VPP700), HP/Convex Exemplar SPP2000, IBM RS/6000 SP P2SC node (120 MHz), NEC SX-4/32, SGI/CRAY T3E, SGI Origin200, and SGI Origin2000. We also report High Performance Fortran (HPF) based NPB results for IBM SP2 Wide Nodes, HP/Convex Exemplar SPP2000, and SGI/CRAY T3D. These results have been submitted by Applied Parallel Research (APR) and Portland Group Inc. (PGI). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks.

Bailey, David H.; Bailey, David; Chancellor, Marisa K. (Technical Monitor)

1997-01-01

77

Performance Characteristics of the Multi-Zone NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

We describe a new suite of computational benchmarks that models applications featuring multiple levels of parallelism. Such parallelism is often available in realistic flow computations on systems of grids, but had not previously been captured in bench-marks. The new suite, named NPB Multi-Zone, is extended from the NAS Parallel Benchmarks suite, and involves solving the application benchmarks LU, BT and SP on collections of loosely coupled discretization meshes. The solutions on the meshes are updated independently, but after each time step they exchange boundary value information. This strategy provides relatively easily exploitable coarse-grain parallelism between meshes. Three reference implementations are available: one serial, one hybrid using the Message Passing Interface (MPI) and OpenMP, and another hybrid using a shared memory multi-level programming model (SMP+OpenMP). We examine the effectiveness of hybrid parallelization paradigms in these implementations on three different parallel computers. We also use an empirical formula to investigate the performance characteristics of the multi-zone benchmarks.

Jin, Haoqiang; VanderWijngaart, Rob F.

2003-01-01

78

Performance Comparison of HPF and MPI Based NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

Compilers supporting High Performance Form (HPF) features first appeared in late 1994 and early 1995 from Applied Parallel Research (APR), Digital Equipment Corporation, and The Portland Group (PGI). IBM introduced an HPF compiler for the IBM RS/6000 SP2 in April of 1996. Over the past two years, these implementations have shown steady improvement in terms of both features and performance. The performance of various hardware/ programming model (HPF and MPI) combinations will be compared, based on latest NAS Parallel Benchmark results, thus providing a cross-machine and cross-model comparison. Specifically, HPF based NPB results will be compared with MPI based NPB results to provide perspective on performance currently obtainable using HPF versus MPI or versus hand-tuned implementations such as those supplied by the hardware vendors. In addition, we would also present NPB, (Version 1.0) performance results for the following systems: DEC Alpha Server 8400 5/440, Fujitsu CAPP Series (VX, VPP300, and VPP700), HP/Convex Exemplar SPP2000, IBM RS/6000 SP P2SC node (120 MHz), NEC SX-4/32, SGI/CRAY T3E, and SGI Origin2000. We would also present sustained performance per dollar for Class B LU, SP and BT benchmarks.

Saini, Subhash

1997-01-01

79

The Use of the MPI Communication Library in the NAS Parallel Benchmarks  

E-print Network

1 The Use of the MPI Communication Library in the NAS Parallel Benchmarks Theodore B. Tabe, Member-- The statistical analysis of traces taken from the NAS Parallel Benchmarks can tell one much about the type Parallel Benchmarks Theodore B. Tabe is with the Advanced Computer Architecture Laboratory, University

Stout, Quentin F.

80

NPB-MPJ: NAS Parallel Benchmarks Implementation for Message-Passing in Java  

E-print Network

NPB-MPJ: NAS Parallel Benchmarks Implementation for Message-Passing in Java Dami´an A. Mall presents NPB-MPJ, the first extensive implementa- tion of the NAS Parallel Benchmarks (NPB), the standard parallel benchmark suite, for Message-Passing in Java (MPJ) libraries. Together with the design

Touriño, Juan

81

Genome-wide identification, classification and expression profiling of nicotianamine synthase (NAS) gene family in maize  

PubMed Central

Background Nicotianamine (NA), a ubiquitous molecule in plants, is an important metal ion chelator and the main precursor for phytosiderophores biosynthesis. Considerable progress has been achieved in cloning and characterizing the functions of nicotianamine synthase (NAS) in plants including barley, Arabidopsis and rice. Maize is not only an important cereal crop, but also a model plant for genetics and evolutionary study. The genome sequencing of maize was completed, and many gene families were identified. Although three NAS genes have been characterized in maize, there is still no systematic identification of maize NAS family by genomic mining. Results In this study, nine NAS genes in maize were identified and their expression patterns in different organs including developing seeds were determined. According to the evolutionary relationship and tissue specific expression profiles of ZmNAS genes, they can be subgrouped into two classes. Moreover, the expression patterns of ZmNAS genes in response to fluctuating metal status were analysed. The class I ZmNAS genes were induced under Fe deficiency and were suppressed under Fe excessive conditions, while the expression pattern of class II genes were opposite to class I. The complementary expression patterns of class I and class II ZmNAS genes confirmed the classification of this family. Furthermore, the histochemical localization of ZmNAS1;1/1;2 and ZmNAS3 were determined using in situ hybridization. It was revealed that ZmNAS1;1/1;2, representing the class I genes, mainly expressed in cortex and stele of roots with sufficient Fe, and its expression can expanded in epidermis, as well as shoot apices under Fe deficient conditions. On the contrary, ZmNAS3, one of the class II genes, was accumulated in axillary meristems, leaf primordia and mesophyll cells. These results suggest that the two classes of ZmNAS genes may be regulated on transcriptional level when responds to various demands for iron uptake, translocation and homeostasis. Conclusion These results provide significant insights into the molecular bases of ZmNAS in balancing iron uptake, translocation and homeostasis in response to fluctuating environmental Fe status. PMID:23575343

2013-01-01

82

Natural Attenuation Software (NAS): A computer program for estimating remediation times of contaminated groundwater  

USGS Publications Warehouse

This paper describes the development and application of a modeling system called Natural Attenuation Software (NAS). NAS was designed as a screening tool to estimate times of remediation (TORs), associated with monitored natural attenuation (MNA), to lower groundwater contaminant concentrations to regulatory limits. Natural attenuation processes that NAS models include advection, dispersion, sorption, biodegradation, and non-aqueous phase liquid (NAPL) dissolution. This paper discusses the three main interactive components of NAS: 1) estimation of the target source concentration required for a plume extent to contract to regulatory limits, 2) estimation of the time required for NAFL contaminants in the source area to attenuate to a predetermined target source concentration, and 3) estimation of the time required for a plume extent to contract to regulatory limits after source reduction. The model's capability is illustrated by results from a case study at a MNA site, where NAS time of remediation estimates compared well with observed monitoring data over multiple years.

Mendez, E.; Widdowson, M.; Brauner, S.; Chapelle, F.; Casey, C.

2004-01-01

83

NAS Parallel Benchmark. Results 11-96: Performance Comparison of HPF and MPI Based NAS Parallel Benchmarks. 1.0  

NASA Technical Reports Server (NTRS)

High Performance Fortran (HPF), the high-level language for parallel Fortran programming, is based on Fortran 90. HALF was defined by an informal standards committee known as the High Performance Fortran Forum (HPFF) in 1993, and modeled on TMC's CM Fortran language. Several HPF features have since been incorporated into the draft ANSI/ISO Fortran 95, the next formal revision of the Fortran standard. HPF allows users to write a single parallel program that can execute on a serial machine, a shared-memory parallel machine, or a distributed-memory parallel machine. HPF eliminates the complex, error-prone task of explicitly specifying how, where, and when to pass messages between processors on distributed-memory machines, or when to synchronize processors on shared-memory machines. HPF is designed in a way that allows the programmer to code an application at a high level, and then selectively optimize portions of the code by dropping into message-passing or calling tuned library routines as 'extrinsics'. Compilers supporting High Performance Fortran features first appeared in late 1994 and early 1995 from Applied Parallel Research (APR) Digital Equipment Corporation, and The Portland Group (PGI). IBM introduced an HPF compiler for the IBM RS/6000 SP/2 in April of 1996. Over the past two years, these implementations have shown steady improvement in terms of both features and performance. The performance of various hardware/ programming model (HPF and MPI (message passing interface)) combinations will be compared, based on latest NAS (NASA Advanced Supercomputing) Parallel Benchmark (NPB) results, thus providing a cross-machine and cross-model comparison. Specifically, HPF based NPB results will be compared with MPI based NPB results to provide perspective on performance currently obtainable using HPF versus MPI or versus hand-tuned implementations such as those supplied by the hardware vendors. In addition we would also present NPB (Version 1.0) performance results for the following systems: DEC Alpha Server 8400 5/440, Fujitsu VPP Series (VX, VPP300, and VPP700), HP/Convex Exemplar SPP2000, IBM RS/6000 SP P2SC node (120 MHz) NEC SX-4/32, SGI/CRAY T3E, SGI Origin2000.

Saini, Subash; Bailey, David; Chancellor, Marisa K. (Technical Monitor)

1997-01-01

84

Multiscale Habitat Selection by Ruffed Grouse at Low Population Densities (Seleccin de Hbitat a Varias Escalas por Bonasa umbellus a Densidades Poblacionales Bajas)  

E-print Network

Multiscale Habitat Selection by Ruffed Grouse at Low Population Densities (Selección de Hábitat HAbITAT SELECTION by RUffED GROUSE AT LOw POPULATION DENSITIES Selección de Hábitat a Varias Escalas

Gutiérrez, R.J.

85

Testing New Programming Paradigms with NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

Over the past decade, high performance computing has evolved rapidly, not only in hardware architectures but also with increasing complexity of real applications. Technologies have been developing to aim at scaling up to thousands of processors on both distributed and shared memory systems. Development of parallel programs on these computers is always a challenging task. Today, writing parallel programs with message passing (e.g. MPI) is the most popular way of achieving scalability and high performance. However, writing message passing programs is difficult and error prone. Recent years new effort has been made in defining new parallel programming paradigms. The best examples are: HPF (based on data parallelism) and OpenMP (based on shared memory parallelism). Both provide simple and clear extensions to sequential programs, thus greatly simplify the tedious tasks encountered in writing message passing programs. HPF is independent of memory hierarchy, however, due to the immaturity of compiler technology its performance is still questionable. Although use of parallel compiler directives is not new, OpenMP offers a portable solution in the shared-memory domain. Another important development involves the tremendous progress in the internet and its associated technology. Although still in its infancy, Java promisses portability in a heterogeneous environment and offers possibility to "compile once and run anywhere." In light of testing these new technologies, we implemented new parallel versions of the NAS Parallel Benchmarks (NPBs) with HPF and OpenMP directives, and extended the work with Java and Java-threads. The purpose of this study is to examine the effectiveness of alternative programming paradigms. NPBs consist of five kernels and three simulated applications that mimic the computation and data movement of large scale computational fluid dynamics (CFD) applications. We started with the serial version included in NPB2.3. Optimization of memory and cache usage was applied to several benchmarks, noticeably BT and SP, resulting in better sequential performance. In order to overcome the lack of an HPF performance model and guide the development of the HPF codes, we employed an empirical performance model for several primitives found in the benchmarks. We encountered a few limitations of HPF, such as lack of supporting the "REDISTRIBUTION" directive and no easy way to handle irregular computation. The parallelization with OpenMP directives was done at the outer-most loop level to achieve the largest granularity. The performance of six HPF and OpenMP benchmarks is compared with their MPI counterparts for the Class-A problem size in the figure in next page. These results were obtained on an SGI Origin2000 (195MHz) with MIPSpro-f77 compiler 7.2.1 for OpenMP and MPI codes and PGI pghpf-2.4.3 compiler with MPI interface for HPF programs.

Jin, H.; Frumkin, M.; Schultz, M.; Yan, J.

2000-01-01

86

1.15?Å resolution structure of the proteasome-assembly chaperone Nas2 PDZ domain  

PubMed Central

The 26S proteasome is a 2.5?MDa protease dedicated to the degradation of ubiquitinated proteins in eukaryotes. The assembly of this complex containing 66 polypeptides is assisted by at least nine proteasome-specific chaperones. One of these, Nas2, binds to the proteasomal AAA-ATPase subunit Rpt5. The PDZ domain of Nas2 binds to the C-terminal tail of Rpt5; however, it does not require the C-terminus of Rpt5 for binding. Here, the 1.15?Å resolution structure of the PDZ domain of Nas2 is reported. This structure will provide a basis for further insights regarding the structure and function of Nas2 in proteasome assembly. PMID:24699731

Singh, Chingakham R.; Lovell, Scott; Mehzabeen, Nurjahan; Chowdhury, Wasimul Q.; Geanes, Eric S.; Battaile, Kevin P.; Roelofs, Jeroen

2014-01-01

87

Low temperature grown GaNAsSb: A promising material for photoconductive switch application  

NASA Astrophysics Data System (ADS)

We report a photoconductive switch using low temperature grown GaNAsSb as the active material. The GaNAsSb layer was grown at 200 °C by molecular beam epitaxy in conjunction with a radio frequency plasma-assisted nitrogen source and a valved antimony cracker source. The low temperature growth of the GaNAsSb layer increased the dark resistivity of the switch and shortened the carrier lifetime. The switch exhibited a dark resistivity of 107 ? cm, a photo-absorption of up to 2.1 ?m, and a carrier lifetime of ˜1.3 ps. These results strongly support the suitability of low temperature grown GaNAsSb in the photoconductive switch application.

Tan, K. H.; Yoon, S. F.; Wicaksono, S.; Loke, W. K.; Li, D. S.; Saadsaoud, N.; Tripon-Canseliet, C.; Lampin, J. F.; Decoster, D.; Chazelas, J.

2013-09-01

88

Mode locked 1550 nm VECSEL using a two quantum wells GaInNAs Saturable Absorber  

Microsoft Academic Search

We report a 2 GHz mode locked vertical external cavity surface emitting laser using a hybrid metal-metamorphic Bragg mirror on the gain structure with a resonant two quantum wells GaInNAs semiconductor saturable absorber mirror (SESAM).

A. Khadour; S. Bouchoule; G. Aubin; J. P. Tourrenc; A. Miard; J. C. Harmand; J. Decobert; J. L. Oudar

2008-01-01

89

Low temperature grown GaNAsSb: A promising material for photoconductive switch application  

SciTech Connect

We report a photoconductive switch using low temperature grown GaNAsSb as the active material. The GaNAsSb layer was grown at 200 °C by molecular beam epitaxy in conjunction with a radio frequency plasma-assisted nitrogen source and a valved antimony cracker source. The low temperature growth of the GaNAsSb layer increased the dark resistivity of the switch and shortened the carrier lifetime. The switch exhibited a dark resistivity of 10{sup 7} ? cm, a photo-absorption of up to 2.1 ?m, and a carrier lifetime of ?1.3 ps. These results strongly support the suitability of low temperature grown GaNAsSb in the photoconductive switch application.

Tan, K. H.; Yoon, S. F.; Wicaksono, S.; Loke, W. K.; Li, D. S. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)] [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Saadsaoud, N.; Tripon-Canseliet, C. [Laboratoire d'Electronique et Electromagnétisme, Pierre and Marie Curie University, 4 Place Jussieu, 75005 Paris (France)] [Laboratoire d'Electronique et Electromagnétisme, Pierre and Marie Curie University, 4 Place Jussieu, 75005 Paris (France); Lampin, J. F.; Decoster, D. [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille, BP 60069, 59652 Villeneuve d'Ascq Cedex (France)] [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille, BP 60069, 59652 Villeneuve d'Ascq Cedex (France); Chazelas, J. [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)] [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)

2013-09-09

90

UAS in the NAS: Survey Responses by ATC, Manned Aircraft Pilots, and UAS Pilots  

NASA Technical Reports Server (NTRS)

NASA currently is working with industry and the Federal Aviation Administration (FAA) to establish future requirements for Unmanned Aircraft Systems (UAS) flying in the National Airspace System (NAS). To work these issues NASA has established a multi-center "UAS Integration in the NAS" project. In order to establish Ground Control Station requirements for UAS, the perspective of each of the major players in NAS operations was desired. Three on-line surveys were administered that focused on Air Traffic Controllers (ATC), pilots of manned aircraft, and pilots of UAS. Follow-up telephone interviews were conducted with some survey respondents. The survey questions addressed UAS control, navigation, and communications from the perspective of small and large unmanned aircraft. Questions also addressed issues of UAS equipage, especially with regard to sense and avoid capabilities. From the civilian ATC and military ATC perspectives, of particular interest are how mixed operations (manned / UAS) have worked in the past and the role of aircraft equipage. Knowledge gained from this information is expected to assist the NASA UAS Integration in the NAS project in directing research foci thus assisting the FAA in the development of rules, regulations, and policies related to UAS in the NAS.

Comstock, James R., Jr.; McAdaragh, Raymon; Ghatas, Rania W.; Burdette, Daniel W.; Trujillo, Anna C.

2014-01-01

91

Improved optical quality of GaNAsSb in the dilute Sb limit  

SciTech Connect

GaNAs(Sb) layers were grown by solid-source molecular-beam epitaxy utilizing a radio frequency (rf) nitrogen plasma source. The samples contained less nitrogen and antimony (0.5%-0.8% N and {<=}2% Sb) than in previous studies and were examined for their optical and electronic properties and any interactions between the elements. Secondary-ion-mass spectrometry, high-resolution x-ray diffraction, electroreflectance (ER) spectroscopy, and photoluminescence (PL) measurements were used to study those properties. We found that the addition of small amounts of antimony enhanced nitrogen incorporation into GaAs, similar to other studies that used 5-15x the mole fraction of antimony. The nitrogen concentration increased with increasing antimony flux. PL measurements indicated an improvement in optical quality with increasing nitrogen and antimony concentrations--contrary to the belief that adding more nitrogen necessarily degrades material quality. We collected and simulated ER spectra to examine the general band properties of the layers. Isoelectronic codoping can explain the improved quality when antimony is added to GaNAs. The improvement in GaNAs with small amounts of antimony holds great promise for improving strain-compensated GaInNAs(Sb)/GaNAs devices.

Yuen, Homan B.; Bank, Seth R.; Wistey, Mark A.; Harris, James S. Jr.; Seong, Maeng-Je; Yoon, Seokhyun; Kudrawiec, Robert; Misiewicz, Jan [Solid State and Photonics Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California 94305-4075 (United States); National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, Colorado 80401 (United States); Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

2005-06-01

92

GaNAsP: An intermediate band semiconductor grown by gas-source molecular beam epitaxy  

SciTech Connect

Dilute nitride GaNAsP thin films were grown via a GaAsP metamorphic buffer on GaP(100) substrate with gas-source molecular beam epitaxy. The compositions of this III-V-V-V compound were determined by channeling Rutherford backscattering spectroscopy and nuclear reaction analysis. Photoreflectance shows two distinctive transitions from the valence band to the split conduction bands due to N incorporation. Photoluminescence and optical absorption show the fundamental bandgap of Ga(N)AsP is largely tailored by the small amount of N. The observed multiband characteristics and the bandgap tunability of GaNAsP are two merits that fit into the intermediate-band solar cell roadmap, and GaNAsP of high crystal quality provides a strong candidate for intermediate band solar cell materials.

Kuang, Y. J. [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States)] [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Yu, K. M.; Walukiewicz, W. [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Kudrawiec, R. [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States) [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Institute of Physics, Wroclaw University of Technology, Wybrzeze, Wyspianskiego 27, 50-370 Wroclaw (Poland); Luce, A. V. [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States) [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Ting, M. [Department of Mechanical Engineering, University of California, Berkeley, California 94720 (United States)] [Department of Mechanical Engineering, University of California, Berkeley, California 94720 (United States); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States)] [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States)

2013-03-18

93

Examination of Frameworks for Safe Integration of Intelligent Small UAS into the NAS  

NASA Technical Reports Server (NTRS)

This paper discusses a proposed framework for the safe integration of small unmanned aerial systems (sUAS) into the National Airspace System (NAS). The paper briefly examines the potential uses of sUAS to build an understanding of the location and frequency of potential future flight operations based on the future applications of the sUAS systems. The paper then examines the types of systems that would be required to meet the application-level demand to determine "classes" of platforms and operations. A framework for categorization of the "intelligence" level of the UAS is postulated for purposes of NAS integration. Finally, constraints on the intelligent systems are postulated to ensure their ease of integration into the NAS.

Logan, Michael J.

2012-01-01

94

Desarrollo de la Escala sobre el Estigma Relacionado con el VIH/SIDA para Profesionales de la Salud mediante el uso de métodos mixtos123  

PubMed Central

El estigma relacionado con el VIH/SIDA continúa siendo un obstáculo para la prevención primaria y secundaria del VIH. Las consecuencias para las personas que viven con la enfermedad han sido muy documentadas y continúan siendo una gran preocupación para las personas que proveen servicios de salud y para aquellas que investigan el tema. Estas consecuencias son preocupantes cuando el estigma emana de profesionales de la salud porque se puede limitar el acceso a los servicios. Uno de los principales obstáculos para la investigación del estigma relacionado con el VIH en Puerto Rico es la falta de instrumentos cuantitativos para evaluar las manifestaciones del estigma entre profesionales de la salud. El objetivo principal de este estudio fue desarrollar y probar las propiedades psicométricas de una escala sobre el estigma relacionado con el VIH/SIDA culturalmente apropiada para personas que proveen servicios de salud puertorriqueñas y desarrollar una versión corta de la escala que pudiera usarse en escenarios clínicos con tiempo limitado. El instrumento desarrollado estuvo basado en evidencia cualitativa recopilada entre profesionales y estudiantes de profesiones de la salud puertorriqueños/as (n=80) y administrado a una muestra de 421 profesionales de la salud en adiestramiento. La escala contenía 12 dimensiones del estigma relacionado con el VIH/SIDA. El análisis cuantitativo corroboró 11 de ellas, teniendo como resultado un instrumento con validez y confiabilidad satisfactoria. Estas dimensiones, a su vez, fueron subcomponentes de un factor de estigma general superior. PMID:20333258

Varas-Díaz, Nelson; Neilands, Torsten B.; Guilamo-Ramos, Vincent; Cintrón Bou, Francheska N.

2009-01-01

95

Test report for the Direct Access Radar/National Airspace System (DARC/NAS) bi-directional interface test  

NASA Astrophysics Data System (ADS)

The results of the DARC/NAS (HOST) bi-directional interface testing are described in this report. The DARC and NAS systems were physically connected by the General Purpose Output (GPO)/General Purpose Input (GPI) lines. Controller and supervisory messages were entered automatically by time from both the DARC and NAS systems. Both systems used common simulated radar data. Results were examined by analyzing recorded data to determine the transparency of the system.

Dimeo, Robert V.; Mullany, T. C.; Tedford, A.; Grossman, L.

1989-01-01

96

General Nitrogen Regulation of Nitrate Assimilation Regulatory Gene nasR Expression in Klebsiella oxytoca M5al  

PubMed Central

Klebsiella oxytoca can assimilate nitrate and nitrite by using enzymes encoded by the nasFEDCBA operon. Expression of the nasF operon is controlled by general nitrogen regulation (Ntr) via the NtrC transcription activator and by pathway-specific nitrate and nitrite induction via the NasR transcription antiterminator. This paper reports our analysis of nasR gene expression. We constructed strains bearing single-copy ?(nasR-lacZ) operon fusions within the chromosomal rhaBAD-rhaSR locus. The expression of ?rhaBS::[?(nasR-lacZ)] operon fusions was induced about 10-fold during nitrogen-limited growth. Induction was reduced in both ntrC and rpoN null mutants, indicating that Ntr control of nasR gene expression requires the NtrC and ?N (?54) proteins. Sequence inspection of the nasR control region reveals an apparent ?N-dependent promoter but no apparent NtrC protein binding sites. Analysis of site-specific mutations coupled with primer extension analysis authenticated the ?N-dependent nasR promoter. Fusion constructs with only about 70 nucleotides (nt) upstream of the transcription initiation site exhibited patterns of ?-galactosidase expression indistinguishable from ?(nasR-lacZ) constructs with about 470 nt upstream. Expression was independent of the Nac protein, implying that NtrC is a direct activator of nasR transcription. Together, these results indicate that nasR gene expression does not require specific upstream NtrC-binding sequences, as previously noted for argT gene expression in Salmonella typhimurium (G. Schmitz, K. Nikaido, and G. F.-L. Ames, Mol. Gen. Genet. 215:107–117, 1988). PMID:10572131

Wu, Stephen Qitu; Chai, Weihang; Lin, Janine T.; Stewart, Valley

1999-01-01

97

Beyond the NAS Parallel Benchmarks: Measuring Dynamic Program Performance and Grid Computing Applications  

NASA Technical Reports Server (NTRS)

The contents include: 1) A brief history of NPB; 2) What is (not) being measured by NPB; 3) Irregular dynamic applications (UA Benchmark); and 4) Wide area distributed computing (NAS Grid Benchmarks-NGB). This paper is presented in viewgraph form.

VanderWijngaart, Rob F.; Biswas, Rupak; Frumkin, Michael; Feng, Huiyu; Biegel, Bryan (Technical Monitor)

2001-01-01

98

NAS: the NAIST user authorization management system for network accesses in consideration of system administration volunteers  

Microsoft Academic Search

The Nara Institute of Science and Technology (NAIST) user Authorization management System for network accesses (NAS) was designed and developed as a campus-network management system for administrators who are not information and communications technology (ICT) experts. Student residents have successfully operated the system in the dormitory network since November 2002, in the staff accommodation network by residents since June 2003,

Motohiro Ichikawa; Yutaka Nakamura; Eiji Kawai; Kazutoshi Fujikawa; Hideki Sunahara

2005-01-01

99

INFLUÊNCIA DAS CONDIÇÕES AMBIENTAIS NAS RELAÇÕES BÁSICAS N:P:K DAS FOLHAS DE ÁRVORES URBANAS  

Microsoft Academic Search

3 RESUMO: Este trabalho investigou a influência das condições ambientais das árvores nas relações dos teores foliares de N, P e K. As espécies utilizadas foram: acer ( Acer negundo L.) e ipê (Tabebuia chrysotricha ( Mart ex DC.) Standl). Foram selecionados locais com diferentes intensidades de tráfego de veículos (tráfego grande, médio, residenciais e parques), condições ambientais ( com

D. Biondi; C. B. Reissmann

100

Today's National Airspace System (NAS) consists of a complex collection of facilities, systems, equipment,  

E-print Network

. · Approximately 13,000 instrument flight proce- dures, including over 1,000 Instrument Landing System (ILS such as microwave landing system (MLS), localizer (LOC), localizer type directional aid (LDA), simplified1-1 Today's National Airspace System (NAS) consists of a complex collection of facilities, systems

Sun, Dengfeng

101

INFLUÊNCIA DE SISTEMAS DE PREPARO E PASTEJO NAS CARACTERÍSTICAS FÍSICAS DO SOLO  

Microsoft Academic Search

RESUMO - No Rio Grande do Sul, os sistemas integrados de agricultura e pecuária estão sendo adotados em extensas áreas que historicamente estavam submetidas ao binômio trigo-soja. Esta mudança na forma de exploração da terra origina uma nova condição que deve ser pesquisada para evitar efeitos indesejáveis no solo. Procurando determinar alterações nas propriedades físicas e mecânicas do solo, durante

MARCELO RESCHUTZEGGER GAGGERO; CARLOS RICARDO TREIN; E GABRIELA IPPOLITI

102

Numerical Applications and Sub-Word Parallelism: The NAS Benchmarks on a Pentium 4  

Microsoft Academic Search

We examine the impact of Pentium 4 SIMD instructions on the Fortran and C versions of the NAS benchmarks, either by compiler vectorization or by assembly code in-lining. If few functions generally profit from the SIMD operations, the ones using complex numbers or random number generators can be efficiently accelerated.

Etiemble Daniel

2002-01-01

103

The Use of the MPI Communication Library in the NAS Parallel Benchmarks  

Microsoft Academic Search

The statistical analysis of traces taken from the NAS Parallel Benchmarks can tell one much aboutthe type of network tra#c that can be expected from scienti#c applications run on distributed memoryparallel computers. For instance, such applications utilize a relatively few number of communication libraryfunctions, the length of their messages is widely varying, they use many more short messages than longones,

Theodore B. Tabe; Quentin F. Stout

1999-01-01

104

Comparison of Origin 2000 and Origin 3000 Using NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

This report describes results of benchmark tests on the Origin 3000 system currently being installed at the NASA Ames National Advanced Supercomputing facility. This machine will ultimately contain 1024 R14K processors. The first part of the system, installed in November, 2000 and named mendel, is an Origin 3000 with 128 R12K processors. For comparison purposes, the tests were also run on lomax, an Origin 2000 with R12K processors. The BT, LU, and SP application benchmarks in the NAS Parallel Benchmark Suite and the kernel benchmark FT were chosen to determine system performance and measure the impact of changes on the machine as it evolves. Having been written to measure performance on Computational Fluid Dynamics applications, these benchmarks are assumed appropriate to represent the NAS workload. Since the NAS runs both message passing (MPI) and shared-memory, compiler directive type codes, both MPI and OpenMP versions of the benchmarks were used. The MPI versions used were the latest official release of the NAS Parallel Benchmarks, version 2.3. The OpenMP versiqns used were PBN3b2, a beta version that is in the process of being released. NPB 2.3 and PBN 3b2 are technically different benchmarks, and NPB results are not directly comparable to PBN results.

Turney, Raymond D.

2001-01-01

105

An efficient parallel algorithm for the 3-D FFT NAS parallel benchmark  

Microsoft Academic Search

We propose an efficient algorithm to implement the 3D NAS FFT benchmark. The proposed algorithm overlaps the communication with the computation. On parallel machines supporting overlap of communication with computation, the proposed algorithm can outperform the non-overlapping version of this algorithm by a factor close to two

R. C. Agarwal; F. G. Gustavson; M. Zubair

1994-01-01

106

NAS Parallel Benchmark (Version 1.0) Results 11-96  

Microsoft Academic Search

The NAS Parallel Benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a ''pencil and paper'' fashion. In other words, the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select

Subhash Saini; David H. Bailey

107

Characterizing Shared-Memory Applications: A Case Study of the NAS Parallel Benchmarks  

Microsoft Academic Search

The objective of this report is to present our characterization of a shared-memoryimplementation of the NAS Parallel Benchmarks (NPB). This characterization is neededto support the design decisions of future shared-memory multiprocessors. This reportpresents two sets of characterization data; the first set is the application characteristicsthat do not change from one hardware configuration to another, and the secondset is the traffic

Gheith A. Abandah

1997-01-01

108

NAS Parallel Conjugate Gradient Benchmark on the Cray T3D  

Microsoft Academic Search

. The NAS Parallel Benchmark [1] kernels were developed to evaluatethe performance of highly-parallel supercomputers. These benchmarks are unstructuredin the sense that they give only an algorithm defining the benchmark; all implementationdetails are left to the programmer. We looked specifically at a kernelto solve an unstructured sparse linear system via the conjugate gradient method,the CG kernel. This kernel was implemented

Tamara L. Gibson

1995-01-01

109

Performance of the NAS Parallel Benchmarks on PVM-Based Networks  

Microsoft Academic Search

The NAS parallel benchmarks are a set of applications that embody the key characteristics of typical processing in computational aerodynamics. Five of these, the kernel benchmarks, have been implemented on the PVM system, a software system for network-based concurrent computing, with a view to determining the efficacy of networked environments for high-performance computational aerodynamics applications. We present results of porting

S. White; A. Alund; V. S. Sunderam

1995-01-01

110

Performance of NAS parallel application-benchmarks on IBM SP1  

Microsoft Academic Search

We present the performance of three application benchmarks (BT, LU, and SP) from the NAS Parallel Benchmark suite on the IBM scalable POWERparallel 1 (SP1) system. We present performance results on both Class A and Class B problem sets. We compare the performance of two communication protocols, MPL and MPL\\/p, and also present results on a cluster of workstations called

Vijay K. Naik

1994-01-01

111

Passively modelocked GaInNAs VECSEL at centre wavelength around 1.3 lm  

E-print Network

Passively modelocked GaInNAs VECSEL at centre wavelength around 1.3 lm A. Rutz, V. Liverini, D-external-cavity surface- emitting laser (VECSEL) is demonstrated for the first time. The VECSEL was optically pumped using to generate red light. Optically pumped VECSELs have potential for both high average output power and near

Keller, Ursula

112

Room-temperature electron spin amplifier based on Ga(In)NAs alloys.  

PubMed

The first experimental demonstration of a spin amplifier at room temperature is presented. An efficient, defect-enabled spin amplifier based on a non-magnetic semiconductor, Ga(In)NAs, is proposed and demonstrated, with a large spin gain (up to 2700% at zero field) for conduction electrons and a high cut-off frequency of up to 1 GHz. PMID:23108727

Puttisong, Yuttapoom; Buyanova, Irina A; Ptak, Aaron J; Tu, Charles W; Geelhaar, Lutz; Riechert, Henning; Chen, Weimin M

2013-02-01

113

ESCALA DE IDENTIFICACI\\  

Microsoft Academic Search

The study describes the construction of a 12 item scale serving to identify the stage within the process of change lived by battered women. Several tests were conducted to measure reliability and concurrent validity of the instrument in a sample of 199 women consulting 11 out of 17 Family Resource Centers of Medellín, Colombia. Women ranged in age from 16

DORIS OSPINA; DIVA ESTELA JARAMILLO; TULIA MARÍA URIBE; GERMÁN C ABARCAS-IGLESIAS

114

Meeting of Experts on NASA's Unmanned Aircraft System (UAS) Integration in the National Airspace Systems (NAS) Project  

NASA Technical Reports Server (NTRS)

Topics discussed include: Aeronautics Research Mission Directorate Integrated Systems Research Program (ISRP) and UAS Integration in the NAS Project; UAS Integration into the NAS Project; Separation Assurance and Collision Avoidance; Pilot Aircraft Interface Objectives/Rationale; Communication; Certification; and Integrated Tests and Evaluations.

Wolfe, Jean; Bauer, Jeff; Bixby, C.J.; Lauderdale, Todd; Shively, Jay; Griner, James; Hayhurst, Kelly

2010-01-01

115

Ubiquity and Diversity of Heterotrophic Bacterial nasA Genes in Diverse Marine Environments.  

PubMed

Nitrate uptake by heterotrophic bacteria plays an important role in marine N cycling. However, few studies have investigated the diversity of environmental nitrate assimilating bacteria (NAB). In this study, the diversity and biogeographical distribution of NAB in several global oceans and particularly in the western Pacific marginal seas were investigated using both cultivation and culture-independent molecular approaches. Phylogenetic analyses based on 16S rRNA and nasA (encoding the large subunit of the assimilatory nitrate reductase) gene sequences indicated that the cultivable NAB in South China Sea belonged to the ?-Proteobacteria, ?-Proteobacteria and CFB (Cytophaga-Flavobacteria-Bacteroides) bacterial groups. In all the environmental samples of the present study, ?-Proteobacteria, ?-Proteobacteria and Bacteroidetes were found to be the dominant nasA-harboring bacteria. Almost all of the ?-Proteobacteria OTUs were classified into three Roseobacter-like groups (I to III). Clone library analysis revealed previously underestimated nasA diversity; e.g. the nasA gene sequences affiliated with ?-Proteobacteria, ?-Proteobacteria and Lentisphaerae were observed in the field investigation for the first time, to the best of our knowledge. The geographical and vertical distributions of seawater nasA-harboring bacteria indicated that NAB were highly diverse and ubiquitously distributed in the studied marginal seas and world oceans. Niche adaptation and separation and/or limited dispersal might mediate the NAB composition and community structure in different water bodies. In the shallow-water Kueishantao hydrothermal vent environment, chemolithoautotrophic sulfur-oxidizing bacteria were the primary NAB, indicating a unique nitrate-assimilating community in this extreme environment. In the coastal water of the East China Sea, the relative abundance of Alteromonas and Roseobacter-like nasA gene sequences responded closely to algal blooms, indicating that NAB may be active participants contributing to the bloom dynamics. Our statistical results suggested that salinity, temperature and nitrate may be some of the key environmental factors controlling the composition and dynamics of the marine NAB communities. PMID:25647610

Jiang, Xuexia; Dang, Hongyue; Jiao, Nianzhi

2015-01-01

116

Ubiquity and Diversity of Heterotrophic Bacterial nasA Genes in Diverse Marine Environments  

PubMed Central

Nitrate uptake by heterotrophic bacteria plays an important role in marine N cycling. However, few studies have investigated the diversity of environmental nitrate assimilating bacteria (NAB). In this study, the diversity and biogeographical distribution of NAB in several global oceans and particularly in the western Pacific marginal seas were investigated using both cultivation and culture-independent molecular approaches. Phylogenetic analyses based on 16S rRNA and nasA (encoding the large subunit of the assimilatory nitrate reductase) gene sequences indicated that the cultivable NAB in South China Sea belonged to the ?-Proteobacteria, ?-Proteobacteria and CFB (Cytophaga-Flavobacteria-Bacteroides) bacterial groups. In all the environmental samples of the present study, ?-Proteobacteria, ?-Proteobacteria and Bacteroidetes were found to be the dominant nasA-harboring bacteria. Almost all of the ?-Proteobacteria OTUs were classified into three Roseobacter-like groups (I to III). Clone library analysis revealed previously underestimated nasA diversity; e.g. the nasA gene sequences affiliated with ?-Proteobacteria, ?-Proteobacteria and Lentisphaerae were observed in the field investigation for the first time, to the best of our knowledge. The geographical and vertical distributions of seawater nasA-harboring bacteria indicated that NAB were highly diverse and ubiquitously distributed in the studied marginal seas and world oceans. Niche adaptation and separation and/or limited dispersal might mediate the NAB composition and community structure in different water bodies. In the shallow-water Kueishantao hydrothermal vent environment, chemolithoautotrophic sulfur-oxidizing bacteria were the primary NAB, indicating a unique nitrate-assimilating community in this extreme environment. In the coastal water of the East China Sea, the relative abundance of Alteromonas and Roseobacter-like nasA gene sequences responded closely to algal blooms, indicating that NAB may be active participants contributing to the bloom dynamics. Our statistical results suggested that salinity, temperature and nitrate may be some of the key environmental factors controlling the composition and dynamics of the marine NAB communities. PMID:25647610

Jiang, Xuexia; Dang, Hongyue; Jiao, Nianzhi

2015-01-01

117

Moth eye antireflection coated GaInP/GaAs/GaInNAs solar cell  

NASA Astrophysics Data System (ADS)

The performance of a GaInP/GaAs/GaInNAs solar cell incorporating AlInP moth eye antireflection coating is reported and compared with the performance of a similar cell comprising TiO2/SiO2 antireflection coating. The moth eye coating exhibits an average reflectance of only 2% within the spectral range from 400 nm to 1600 nm. EQE measurements revealed absorption-related losses in the AlInP moth eye coating at wavelengths below 510 nm. Short wavelength absorption decreases the current generation in the top GaInP junction by 10%. Despite the absorption losses, the moth eye patterned GaInP/GaAs/GaInNAs solar cell exhibited higher current generation under AM1.5G real sun illumination.

Aho, Arto; Tommila, Juha; Tukiainen, Antti; Polojärvi, Ville; Niemi, Tapio; Guina, Mircea

2014-09-01

118

Object-Oriented Implementation of the NAS Parallel Benchmarks using Charm++  

NASA Technical Reports Server (NTRS)

This report describes experiences with implementing the NAS Computational Fluid Dynamics benchmarks using a parallel object-oriented language, Charm++. Our main objective in implementing the NAS CFD kernel benchmarks was to develop a code that could be used to easily experiment with different domain decomposition strategies and dynamic load balancing. We also wished to leverage the object-orientation provided by the Charm++ parallel object-oriented language, to develop reusable abstractions that would simplify the process of developing parallel applications. We first describe the Charm++ parallel programming model and the parallel object array abstraction, then go into detail about each of the Scalar Pentadiagonal (SP) and Lower/Upper Triangular (LU) benchmarks, along with performance results. Finally we conclude with an evaluation of the methodology used.

Krishnan, Sanjeev; Bhandarkar, Milind; Kale, Laxmikant V.

1996-01-01

119

Al-enhanced N incorporation in GaNAs alloys grown by chemical beam epitaxy  

NASA Astrophysics Data System (ADS)

The N incorporation is studied in AlGaNAs with low Al content grown by chemical beam epitaxy at low temperature using dimethylhydrazine as the N precursor. The incorporation efficiency is significantly enhanced by introducing a relatively low Al concentration. The relation between the N incorporation and N/(N+As) flow ratio for Al concentrations of 0-15% is presented. The highest N incorporation and the best AlGaNAs crystal quality are obtained between 400 °C and 440 °C, where the growth mode starts to change from 2D to 3D. The activation energies for N incorporation in both the 2D and 3D growth mode regions are extracted.

Kolhatkar, Gitanjali; Boucherif, Abderraouf; Valdivia, Christopher E.; Wallace, Steven G.; Fafard, Simon; Aimez, Vincent; Arès, Richard

2013-10-01

120

Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project  

NASA Technical Reports Server (NTRS)

NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication system prototype radio, operating on recently allocated UAS frequency spectrum bands. The prototype radio will be used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current status of the design, development, and flight test planning for this prototype radio.

Griner, James H.

2013-01-01

121

Carrier trapping and escape times in p-i-n GaInNAs MQW structures  

PubMed Central

We used a semi-classical model to describe carrier capture into and thermionic escape from GaInNAs/GaAs multiple quantum wells (MQWs) situated within the intrinsic region of a GaAs p-i-n junction. The results are used to explain photocurrent oscillations with applied bias observed in these structures, in terms of charge accumulation and resonance tunnelling. PMID:24417767

2014-01-01

122

Evaluation of the HPF\\/JA Extensions on Fujitsu VPP Using the NAS Parallel Benchmarks  

Microsoft Academic Search

We have ported 5 codes in APR’s HPF implementation of NAS Parallel benchmark, so that it is conformable to HPF 2.0 and HPF\\/JA\\u000a specification. The porting is done with the full usage of HPF 2.0 and HPF\\/JA new features, while the base Fortran codes remain\\u000a almost unmodified. Then we have measured the performance of these benchmark codes on Fujitsu VPP800

Kae Asaoka; Akio Hirano; Yasuo Okabe; Masanori Kanazawa

2002-01-01

123

NAS Parallel Benchmarks I/O Version 2.4. 2.4  

NASA Technical Reports Server (NTRS)

We describe a benchmark problem, based on the Block-Tridiagonal (BT) problem of the NAS Parallel Benchmarks (NPB), which is used to test the output capabilities of high-performance computing systems, especially parallel systems. We also present a source code implementation of the benchmark, called NPBIO2.4-MPI, based on the MPI implementation of NPB, using a variety of ways to write the computed solutions to file.

Wong, Parkson; VanderWijngaart, Rob F.; Biegel, Bryan A. (Technical Monitor)

2002-01-01

124

Functional Requirements Document for HALE UAS Operations in the NAS: Step 1. Version 3  

NASA Technical Reports Server (NTRS)

The purpose of this Functional Requirements Document (FRD) is to compile the functional requirements needed to achieve the Access 5 Vision of "operating High Altitude, Long Endurance (HALE) Unmanned Aircraft Systems (UAS) routinely, safely, and reliably in the national airspace system (NAS)" for Step 1. These functional requirements could support the development of a minimum set of policies, procedures and standards by the Federal Aviation Administration (FAA) and various standards organizations. It is envisioned that this comprehensive body of work will enable the FAA to establish and approve regulations to govern safe operation of UAS in the NAS on a routine or daily "file and fly" basis. The approach used to derive the functional requirements found within this FRD was to decompose the operational requirements and objectives identified within the Access 5 Concept of Operations (CONOPS) into the functions needed to routinely and safely operate a HALE UAS in the NAS. As a result, four major functional areas evolved to enable routine and safe UAS operations for an on-demand basis in the NAS. These four major functions are: Aviate, Navigate, Communicate, and Avoid Hazards. All of the functional requirements within this document can be directly traceable to one of these four major functions. Some functions, however, are traceable to several, or even all, of these four major functions. These cross-cutting functional requirements support the "Command / Control: function as well as the "Manage Contingencies" function. The requirements associated to these high-level functions and all of their supporting low-level functions are addressed in subsequent sections of this document.

2006-01-01

125

NAS technical summaries: Numerical aerodynamic simulation program, March 1991 - February 1992  

NASA Technical Reports Server (NTRS)

NASA created the Numerical Aerodynamic Simulation (NAS) Program in 1987 to focus resources on solving critical problems in aeroscience and related disciplines by utilizing the power of the most advanced supercomputers available. The NAS Program provides scientists with the necessary computing power to solve today's most demanding computational fluid dynamics problems and serves as a pathfinder in integrating leading-edge supercomputing technologies, thus benefiting other supercomputer centers in Government and industry. This report contains selected scientific results from the 1991-92 NAS Operational Year, March 4, 1991 to March 3, 1992, which is the fifth year of operation. During this year, the scientific community was given access to a Cray-2 and a Cray Y-MP. The Cray-2, the first generation supercomputer, has four processors, 256 megawords of central memory, and a total sustained speed of 250 million floating point operations per second. The Cray Y-MP, the second generation supercomputer, has eight processors and a total sustained speed of one billion floating point operations per second. Additional memory was installed this year, doubling capacity from 128 to 256 megawords of solid-state storage-device memory. Because of its higher performance, the Cray Y-MP delivered approximately 77 percent of the total number of supercomputer hours used during this year.

1992-01-01

126

Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project. NASA Contributions to the SARP WC Definition  

NASA Technical Reports Server (NTRS)

To better inform sense and avoid research needs and to understand ongoing investigation of potential solutions that ultimately lead to the assisting the FAA with their Congressional mandate to fly UAS in the NAS.

Randall, Debra K.; Consiglio, Maria Cristina; Santiago, Confesor

2014-01-01

127

Effect of antimony on the deep-level traps in GaInNAsSb thin films  

SciTech Connect

Admittance spectroscopy has been performed to investigate the effect of antimony (Sb) on GaInNAs material in relation to the deep-level defects in this material. Two electron traps, E1 and E2 at an energy level 0.12 and 0.41?eV below the conduction band (E{sub C}), respectively, were found in undoped GaInNAs. Bias-voltage dependent admittance confirmed that E1 is an interface-type defect being spatially localized at the GaInNAs/GaAs interface, while E2 is a bulk-type defect located around mid-gap of GaInNAs layer. Introduction of Sb improved the material quality which was evident from the reduction of both the interface and bulk-type defects.

Islam, Muhammad Monirul, E-mail: islam.monir.ke@u.tsukuba.ac.jp; Miyashita, Naoya; Ahsan, Nazmul; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro ku, Tokyo 153-8904 (Japan); Sakurai, Takeaki; Akimoto, Katsuhiro [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)

2014-09-15

128

Material properties of GaInNAs for long-wavelength laser diodes with excellent high-temperature performance  

Microsoft Academic Search

We propose the application of GaInNAs in laser diodes. This novel material is very attractive for overcoming the poor temperature characteristics of conventional InGaAsP-based long-wavelength LDs, because the electron overflow from the wells to the barrier layers at high temperatures can be suppressed because of the very deep quantum wells. GaInNAs is also promising for the fabrication of long-wavelength vertical-cavity

M. Kondow; T. Kitatani; K. Nakahara; K. Uomi

1998-01-01

129

Improved container electrode coatings for Na/S battery systems. Final report  

SciTech Connect

Current sodium sulfur (Na/S) battery systems utilize the fast ion conducting properties of sodium beta{double_prime}-alumina electrolyte (BASE) to create high energy density sodium-sulfur electrochemical cells which can be used as components of secondary batteries. Since the days when these cells were invented at the Ford Motor Company Scientific Laboratory by J.T. Kummer and N. Weber, problems with container electrode corrosion have troubled the Na/S systems that have been developed in the many laboratories. In an unpublished investigation carried out at the Ford Motor Company laboratory, it was shown that titanium nitride films sputter deposited onto aluminum substrates under the appropriate conditions can exhibit excellent resistance to corrosion by sodium polysulfide melts. In the work carried out here, the corrosion resistant properties of TiN coatings sputter deposited on Al substrates have been investigated. TiN sputter coated aluminum samples were tested under static conditions in sodium sulfide melts and in Na/S cells under the range of electrochemical conditions needed for battery operation. The sputter deposited coatings produced in these experiments exhibited satisfactory corrosion resistance in the static tests but degraded under full cell operation. Tests of TiN coatings deposited by reactive ion-plating (IP), a common commercial process, showed excellent corrosion and electrical performance in both static and complete cell testing. Charge/discharge testing of sulfur core cells with IP coatings for over 350 cycles to 70 % depth of discharge has shown only very minor changes in cell performance and the tests are continuing.

Hunt, T.K. [Environmental Research Institute of Michigan, Ann Arbor, MI (United States). Applications Development Dept.

1995-08-01

130

Communication Improvement for the LU NAS Parallel Benchmark: A Model for Efficient Parallel Relaxation Schemes  

NASA Technical Reports Server (NTRS)

The first release of the MPI version of the LU NAS Parallel Benchmark (NPB2.0) performed poorly compared to its companion NPB2.0 codes. The later LU release (NPB2.1 & 2.2) runs up to two and a half times faster, thanks to a revised point access scheme and related communications scheme. The new scheme sends substantially fewer messages. is cache "friendly", and has a better load balance. We detail the, observations and modifications that resulted in this efficiency improvement, and show that the poor behavior of the original code resulted from deriving a message passing scheme from an algorithm originally devised for a vector architecture.

Yarrow, Maurice; VanderWijngaart, Rob; Kutler, Paul (Technical Monitor)

1997-01-01

131

NAS (Numerical Aerodynamic Simulation Program) technical summaries, March 1989 - February 1990  

NASA Technical Reports Server (NTRS)

Given here are selected scientific results from the Numerical Aerodynamic Simulation (NAS) Program's third year of operation. During this year, the scientific community was given access to a Cray-2 and a Cray Y-MP supercomputer. Topics covered include flow field analysis of fighter wing configurations, large-scale ocean modeling, the Space Shuttle flow field, advanced computational fluid dynamics (CFD) codes for rotary-wing airloads and performance prediction, turbulence modeling of separated flows, airloads and acoustics of rotorcraft, vortex-induced nonlinearities on submarines, and standing oblique detonation waves.

1990-01-01

132

The OpenMP Implementation of NAS Parallel Benchmarks and its Performance  

NASA Technical Reports Server (NTRS)

As the new ccNUMA architecture became popular in recent years, parallel programming with compiler directives on these machines has evolved to accommodate new needs. In this study, we examine the effectiveness of OpenMP directives for parallelizing the NAS Parallel Benchmarks. Implementation details will be discussed and performance will be compared with the MPI implementation. We have demonstrated that OpenMP can achieve very good results for parallelization on a shared memory system, but effective use of memory and cache is very important.

Jin, Hao-Qiang; Frumkin, Michael; Yan, Jerry

1999-01-01

133

Quality of life assessment in intellectual disabilities: The Escala Pessoal de Resultados versus the World Health Quality of Life-BREF.  

PubMed

The aim of this study is to compare the applications of the Escala Pessoal de Resultados (EPR) and the World Health Quality of Life-BREF (WHOQOL-BREF) in quality of life (QOL) assessment of people with intellectual disabilities (ID). A total of 216 adults with ID were assessed (age ranging from 18 to 64 years; 128 people were diagnosed with mild, and 88 with moderate ID). The two scales were administered to each person to obtain their perception about their QOL. Statistically significant correlations (weak to moderate) were observed between both scales. The EPR and the WHOQOL-BREF demonstrated adequate reliability, construct, and discriminant validity in our sample. However, the group of adults with moderate ID scored higher on the WHOQOL-BREF than on the EPR. Results indicated that the two assessment instruments aim to evaluate different measures, and seem to be not interchangeable. PMID:25481536

Simões, Cristina; Santos, Sofia; Claes, Claudia

2015-02-01

134

Web Prep: How to Prepare NAS Reports For Publication on the Web  

NASA Technical Reports Server (NTRS)

This document contains specific advice and requirements for NASA Ames Code IN authors of NAS reports. Much of the information may be of interest to other authors writing for the Web. WebPrep has a graphic Table of Contents in the form of a WebToon, which simulates a discussion between a scientist and a Web publishing consultant. In the WebToon, Frequently Asked Questions about preparing reports for the Web are linked to relevant text in the body of this document. We also provide a text-only Table of Contents. The text for this document is divided into chapters: each chapter corresponds to one frame of the WebToons. The chapter topics are: converting text to HTML, converting 2D graphic images to gif, creating imagemaps and tables, converting movie and audio files to Web formats, supplying 3D interactive data, and (briefly) JAVA capabilities. The last chapter is specifically for NAS staff authors. The Glossary-Index lists web related words and links to topics covered in the main text.

Walatka, Pamela; Balakrishnan, Prithika; Clucas, Jean; McCabe, R. Kevin; Felchle, Gail; Brickell, Cristy

1996-01-01

135

Simultaneous Quantification of Indium and Nitrogen Concentration in InGaNAs Using HAADF-STEM.  

PubMed

To unambiguously evaluate the indium and nitrogen concentrations in In x Ga1-x N y As1-y , two independent sources of information must be obtained experimentally. Based on high-resolution scanning transmission electron microscopy (STEM) images taken with a high-angle annular dark-field (HAADF) detector the strain state of the InGaNAs quantum well is determined as well as its characteristic HAADF-scattering intensity. The strain state is evaluated by applying elasticity theory and the HAADF intensity is used for a comparison with multislice simulations. The combination of both allows for determination of the chemical composition where the results are in accordance with X-ray diffraction measurements, three-dimensional atom probe tomography, and further transmission electron microscopy analysis. The HAADF-STEM evaluation was used to investigate the influence of As-stabilized annealing on the InGaNAs/GaAs sample. Photoluminescence measurements show an annealing-induced blue shift of the emission wavelength. The chemical analysis precludes an elemental diffusion as origin of the energy shift-instead the results are in agreement with a model based on an annealing-induced redistribution of the atomic next-neighbor configuration. PMID:25268110

Grieb, Tim; Müller, Knut; Cadel, Emmanuel; Beyer, Andreas; Schowalter, Marco; Talbot, Etienne; Volz, Kerstin; Rosenauer, Andreas

2014-12-01

136

Growth optimization and optical properties of AlGaNAs alloys  

SciTech Connect

The effect of Al on the surface morphology of chemical beam epitaxy grown AlGaNAs alloys is studied. Pits attributed to N clustering appearing on the dilute nitride surface become smaller, denser, and more uniformly distributed in the presence of Al. This reveals that the introduction of Al results in more homogenous N atoms spatial distribution. A growth temperature study reveals the formation of 3D structures at high temperature due to phase separation. The density of these structures decreases, while their diameter and height increase when the temperature is raised from 380?°C to 565?°C. At growth temperatures in the 380–420?°C range, the phase separation is suppressed and the growth mode is 2D. At 420?°C, the N incorporation is also maximized, making it the optimum temperature. The absorption coefficient and the bandgap of AlGaNAs alloys are extracted from transmittance measurement. A good agreement is obtained between the experimentally measured bandgap and the theoretical values calculated using the band anticrossing model. A bandgap as low as 1.22?eV was reached using Al and N concentrations of ?15% and ?3.4%, respectively.

Kolhatkar, Gitanjali; Boucherif, Abderraouf; Aimez, Vincent; Arès, Richard, E-mail: Richard.Ares@USherbrooke.ca [Institut interdisciplinaire d'innovation technologique (3IT), Université de Sherbrooke, 3000, boul. Université, J1K 0A5 Sherbrooke, Québec (Canada); Laboratoire Nanotechnologies Nanosystèmes (LN2)- CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke J1K OA5, Québec (Canada); Valdivia, Christopher E.; Wallace, Steven G.; Fafard, Simon [Cyrium Technologies Inc., 50 Hines Road, K2K 2M5 Ottawa, Ontario (Canada)

2014-04-28

137

Growth and characterisation of Ga(NAsBi) alloy by metal-organic vapour phase epitaxy  

NASA Astrophysics Data System (ADS)

This paper summarises results of the epitaxial growth of Ga(NAsBi) by metal-organic vapour phase epitaxy (MOVPE) and the subsequent optical and structural characterisations of the samples. Ga(NAsBi)/GaAs multi-quantum well (MQW) samples are grown at 400 °C and single layers at 450 °C on GaAs (001) substrates. Triethylgallium (TEGa), tertiarybutylarsine (TBAs), trimethylbismuth (TMBi) and unsymmetrical dimethylhydrazine (UDMHy) are used as precursors. Secondary ion mass spectrometry (SIMS) shows that the Bi content is independent of the N content in the alloy. It is found that the N content depends on both UDMHy and TMBi supply during growth. High resolution X-ray diffraction (HR-XRD), scanning transmission electron microscopy (STEM) and atomic force microscopy (AFM) measurements show that samples with good crystalline quality can be realised. For samples containing 1.8% Bi and up to 1.8% N grown at 450 °C, photoreflectance spectroscopy (PR) shows a decrease in the band gap with increasing N content of 141±22 meV/% N.

Bushell, Z. L.; Ludewig, P.; Knaub, N.; Batool, Z.; Hild, K.; Stolz, W.; Sweeney, S. J.; Volz, K.

2014-06-01

138

NAS Demand Predictions, Transportation Systems Analysis Model (TSAM) Compared with Other Forecasts  

NASA Technical Reports Server (NTRS)

The current work incorporates the Transportation Systems Analysis Model (TSAM) to predict the future demand for airline travel. TSAM is a multi-mode, national model that predicts the demand for all long distance travel at a county level based upon population and demographics. The model conducts a mode choice analysis to compute the demand for commercial airline travel based upon the traveler s purpose of the trip, value of time, cost and time of the trip,. The county demand for airline travel is then aggregated (or distributed) to the airport level, and the enplanement demand at commercial airports is modeled. With the growth in flight demand, and utilizing current airline flight schedules, the Fratar algorithm is used to develop future flight schedules in the NAS. The projected flights can then be flown through air transportation simulators to quantify the ability of the NAS to meet future demand. A major strength of the TSAM analysis is that scenario planning can be conducted to quantify capacity requirements at individual airports, based upon different future scenarios. Different demographic scenarios can be analyzed to model the demand sensitivity to them. Also, it is fairly well know, but not well modeled at the airport level, that the demand for travel is highly dependent on the cost of travel, or the fare yield of the airline industry. The FAA projects the fare yield (in constant year dollars) to keep decreasing into the future. The magnitude and/or direction of these projections can be suspect in light of the general lack of airline profits and the large rises in airline fuel cost. Also, changes in travel time and convenience have an influence on the demand for air travel, especially for business travel. Future planners cannot easily conduct sensitivity studies of future demand with the FAA TAF data, nor with the Boeing or Airbus projections. In TSAM many factors can be parameterized and various demand sensitivities can be predicted for future travel. These resulting demand scenarios can be incorporated into future flight schedules, therefore providing a quantifiable demand for flights in the NAS for a range of futures. In addition, new future airline business scenarios are investigated that illustrate when direct flights can replace connecting flights and larger aircraft can be substituted, only when justified by demand.

Viken, Jeff; Dollyhigh, Samuel; Smith, Jeremy; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

2006-01-01

139

Utilizing Traveler Demand Modeling to Predict Future Commercial Flight Schedules in the NAS  

NASA Technical Reports Server (NTRS)

The current work incorporates the Transportation Systems Analysis Model (TSAM) to predict the future demand for airline travel. TSAM is a multi-mode, national model that predicts the demand for all long distance travel at a county level based upon population and demographics. The model conducts a mode choice analysis to compute the demand for commercial airline travel based upon the traveler s purpose of the trip, value of time, cost and time of the trip,. The county demand for airline travel is then aggregated (or distributed) to the airport level, and the enplanement demand at commercial airports is modeled. With the growth in flight demand, and utilizing current airline flight schedules, the Fratar algorithm is used to develop future flight schedules in the NAS. The projected flights can then be flown through air transportation simulators to quantify the ability of the NAS to meet future demand. A major strength of the TSAM analysis is that scenario planning can be conducted to quantify capacity requirements at individual airports, based upon different future scenarios. Different demographic scenarios can be analyzed to model the demand sensitivity to them. Also, it is fairly well know, but not well modeled at the airport level, that the demand for travel is highly dependent on the cost of travel, or the fare yield of the airline industry. The FAA projects the fare yield (in constant year dollars) to keep decreasing into the future. The magnitude and/or direction of these projections can be suspect in light of the general lack of airline profits and the large rises in airline fuel cost. Also, changes in travel time and convenience have an influence on the demand for air travel, especially for business travel. Future planners cannot easily conduct sensitivity studies of future demand with the FAA TAF data, nor with the Boeing or Airbus projections. In TSAM many factors can be parameterized and various demand sensitivities can be predicted for future travel. These resulting demand scenarios can be incorporated into future flight schedules, therefore providing a quantifiable demand for flights in the NAS for a range of futures. In addition, new future airline business scenarios are investigated that illustrate when direct flights can replace connecting flights and larger aircraft can be substituted, only when justified by demand.

Viken, Jeff; Dollyhigh, Samuel; Smith, Jeremy; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

2006-01-01

140

Comparison of 250 MHz R10K Origin 2000 and 400 MHz Origin 2000 Using NAS Parallel Benchmarks  

NASA Technical Reports Server (NTRS)

This report describes results of benchmark tests on Steger, a 250 MHz Origin 2000 system with R10K processors, currently installed at the NASA Ames National Advanced Supercomputing (NAS) facility. For comparison purposes, the tests were also run on Lomax, a 400 MHz Origin 2000 with R12K processors. The BT, LU, and SP application benchmarks in the NAS Parallel Benchmark Suite and the kernel benchmark FT were chosen to measure system performance. Having been written to measure performance on Computational Fluid Dynamics applications, these benchmarks are assumed appropriate to represent the NAS workload. Since the NAS runs both message passing (MPI) and shared-memory, compiler directive type codes, both MPI and OpenMP versions of the benchmarks were used. The MPI versions used were the latest official release of the NAS Parallel Benchmarks, version 2.3. The OpenMP versions used were PBN3b2, a beta version that is in the process of being released. NPB 2.3 and PBN3b2 are technically different benchmarks, and NPB results are not directly comparable to PBN results.

Turney, Raymond D.; Thigpen, William W. (Technical Monitor)

2001-01-01

141

Characterization of a Dominant Electron Trap in GaNAs Using Deep-Level Spectroscopy  

SciTech Connect

Dilute-nitrogen GaNAs epitaxial layers grown by metal-organic chemical vapor deposition were characterized by deep-level transient spectroscopy (DLTS). For all samples, the dominant DLTS signal corresponds to an electron trap having an activation energy of about 0.25 to 0.35 eV. The minority-carrier trap density in the p-type material is quantified based on computer simulation of the devices. The simulations show that only about 2% of the traps in the depleted layer are filled during the transient. The fraction of the traps that are filled depends strongly on the depth of the trap, but only weakly on the doping of the layers and on the conduction-band offset. The simulations provide a pathway to obtain semi-quantitative data for analysis of minority-carrier traps by DLTS.

Johnston, S. W.; Kurtz, S. R.

2006-08-01

142

Security Risk Assessment Process for UAS in the NAS CNPC Architecture  

NASA Technical Reports Server (NTRS)

This informational paper discusses the risk assessment process conducted to analyze Control and Non-Payload Communications (CNPC) architectures for integrating civil Unmanned Aircraft Systems (UAS) into the National Airspace System (NAS). The assessment employs the National Institute of Standards and Technology (NIST) Risk Management framework to identify threats, vulnerabilities, and risks to these architectures and recommends corresponding mitigating security controls. This process builds upon earlier work performed by RTCA Special Committee (SC) 203 and the Federal Aviation Administration (FAA) to roadmap the risk assessment methodology and to identify categories of information security risks that pose a significant impact to aeronautical communications systems. A description of the deviations from the typical process is described in regards to this aeronautical communications system. Due to the sensitive nature of the information, data resulting from the risk assessment pertaining to threats, vulnerabilities, and risks is beyond the scope of this paper.

Iannicca, Dennis C.; Young, Dennis P.; Thadani, Suresh K.; Winter, Gilbert A.

2013-01-01

143

Development of computer program NAS3D using Vector processing for geometric nonlinear analysis of structures  

NASA Technical Reports Server (NTRS)

An algorithm for vectorized computation of stiffness matrices of an 8 noded isoparametric hexahedron element for geometric nonlinear analysis was developed. This was used in conjunction with the earlier 2-D program GAMNAS to develop the new program NAS3D for geometric nonlinear analysis. A conventional, modified Newton-Raphson process is used for the nonlinear analysis. New schemes for the computation of stiffness and strain energy release rates is presented. The organization the program is explained and some results on four sample problems are given. The study of CPU times showed that savings by a factor of 11 to 13 were achieved when vectorized computation was used for the stiffness instead of the conventional scalar one. Finally, the scheme of inputting data is explained.

Mangalgiri, P. D.; Prabhakaran, R.

1986-01-01

144

Security Risk Assessment Process for UAS in the NAS CNPC Architecture  

NASA Technical Reports Server (NTRS)

This informational paper discusses the risk assessment process conducted to analyze Control and Non-Payload Communications (CNPC) architectures for integrating civil Unmanned Aircraft Systems (UAS) into the National Airspace System (NAS). The assessment employs the National Institute of Standards and Technology (NIST) Risk Management framework to identify threats, vulnerabilities, and risks to these architectures and recommends corresponding mitigating security controls. This process builds upon earlier work performed by RTCA Special Committee (SC) 203 and the Federal Aviation Administration (FAA) to roadmap the risk assessment methodology and to identify categories of information security risks that pose a significant impact to aeronautical communications systems. A description of the deviations from the typical process is described in regards to this aeronautical communications system. Due to the sensitive nature of the information, data resulting from the risk assessment pertaining to threats, vulnerabilities, and risks is beyond the scope of this paper

Iannicca, Dennis Christopher; Young, Daniel Paul; Suresh, Thadhani; Winter, Gilbert A.

2013-01-01

145

Efficient GaInNAs Gain Mirrors for Semiconductor Disk Lasers at 1.18 ?m and 1.22 ?m  

NASA Astrophysics Data System (ADS)

We report two GaInNAs/GaAs semiconductor disk lasers emitting at the wavelengths of 1180 nm and 1220 nm. The lasers generated 5 W and 7 W output powers, respectively, at a mount temperature of 15° C. Both the gain mirrors were grown by molecular beam epitaxy and consisted of a GaAs/AlAs distributed Bragg reflector and an active region with 10 GaInNAs/GaNAs/GaAs QWs.

Korpijärvi, Ville-Markus; Puustinen, Janne; Leinonen, Tomi; Rautiainen, Jussi; Härkönen, Antti; Hakkarainen, Teemu; Guina, Mircea

2010-11-01

146

Right and Wrong and Cultural Diversity: Replication of the 2002 NAS/Zogby Poll on Business Ethics  

ERIC Educational Resources Information Center

In April 2002, a NAS/Zogby poll found that only a quarter of sampled students perceived uniform standards of "right and wrong" and that most students felt that ethical behavior depends on cultural diversity. In this effort to replicate those findings in a larger sample of American college students, the authors obtained results that contradict the…

Ludlum, Marty; Mascaloinov, Sergei

2004-01-01

147

One-dimensional carbon-sulfur composite fibers for Na-S rechargeable batteries operating at room temperature.  

PubMed

Na-S batteries are one type of molten salt battery and have been used to support stationary energy storage systems for several decades. Despite their successful applications based on long cycle lives and low cost of raw materials, Na-S cells require high temperatures above 300 °C for their operations, limiting their propagation into a wide range of applications. Herein, we demonstrate that Na-S cells with solid state active materials can perform well even at room temperature when sulfur-containing carbon composites generated from a simple thermal reaction were used as sulfur positive electrodes. Furthermore, this structure turned out to be robust during repeated (de)sodiation for ~500 cycles and enabled extraordinarily high rate performance when one-dimensional morphology is adopted using scalable electrospinning processes. The current study suggests that solid-state Na-S cells with appropriate atomic configurations of sulfur active materials could cover diverse battery applications where cost of raw materials is critical. PMID:23981085

Hwang, Tae Hoon; Jung, Dae Soo; Kim, Joo-Seong; Kim, Byung Gon; Choi, Jang Wook

2013-09-11

148

THE NAS PARALLEL BENCHMARKS D. Bailey, E. Barszcz, J. Barton, D. Browning, R. Carter, L. Dagum, R.  

E-print Network

THE NAS PARALLEL BENCHMARKS D. Bailey, E. Barszcz, J. Barton, D. Browning, R. Carter, L. Dagum, R parallel supercomputers. These benchmarks consist of five parallel kernels and three simulated application. In this way many of the difficulties associated with conven- tional benchmarking approaches on highly parallel

Bailey, David H.

149

Theoretical studies of optical gain tuning by hydrostatic pressure in GaInNAs/GaAs quantum wells  

SciTech Connect

In order to describe theoretically the tuning of the optical gain by hydrostatic pressure in GaInNAs/GaAs quantum wells (QWs), the optical gain calculations within kp approach were developed and applied for N-containing and N-free QWs. The electronic band structure and the optical gain for GaInNAs/GaAs QW were calculated within the 10-band kp model which takes into account the interaction of electron levels in the QW with the nitrogen resonant level in GaInNAs. It has been shown that this interaction increases with the hydrostatic pressure and as a result the optical gain for GaInNAs/GaAs QW decreases by about 40% and 80% for transverse electric and transverse magnetic modes, respectively, for the hydrostatic pressure change from 0 to 40 kilobars. Such an effect is not observed for N-free QWs where the dispersion of electron and hole energies remains unchanged with the hydrostatic pressure. This is due to the fact that the conduction and valence band potentials in GaInAs/GaAs QW scale linearly with the hydrostatic pressure.

Gladysiewicz, M.; Wartak, M. S. [Institute of Physics, Wroclaw University of Technology, 50-370 Wroclaw, Wybrzeze Wyspianskiego 27 (Poland); Department of Physics and Computer Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Kudrawiec, R. [Institute of Physics, Wroclaw University of Technology, 50-370 Wroclaw, Wybrzeze Wyspianskiego 27 (Poland)

2014-01-21

150

Air Traffic Controller Performance and Acceptability of Multiple UAS in a Simulated NAS Environment  

NASA Technical Reports Server (NTRS)

Previously, we showed that air traffic controllers (ATCos) rated UAS pilot verbal response latencies as acceptable when a 1.5 s delay was added to the UAS pilot responses, but a 5 s delay was rated as mostly unacceptable. In the present study we determined whether a 1.5 s added delay in the UAS pilots' verbal communications would affect ATCos interactions with UAS and other conventional aircraft when the number and speed of the UAS were manipulated. Eight radar-certified ATCos participated in this simulation. The ATCos managed a medium altitude sector containing arrival aircraft, en route aircraft, and one to four UAS. The UAS were conducting a surveillance mission and flew at either a "slow" or "fast" speed. We measured both UAS and conventional pilots' verbal communication latencies, and obtained ATCos' acceptability ratings for these latencies. Although the UAS pilot response latencies were longer than those of conventional pilots, the ATCos rated UAS pilot verbal communication latencies to be as acceptable as those of conventional pilots. Because the overall traffic load within the sector was held constant, ATCos only performed slightly worse when multiple UAS were in their sector compared to when only one UAS was in the sector. Implications of these findings for UAS integration in the NAS are discussed.

Vu, Kim-Phuong L.; Strybel, Thomas; Chiappe, Dan; Morales, Greg; Battiste, Vernol; Shively, Robert Jay

2014-01-01

151

MPI, HPF or OpenMP: A Study with the NAS Benchmarks  

NASA Technical Reports Server (NTRS)

Porting applications to new high performance parallel and distributed platforms is a challenging task. Writing parallel code by hand is time consuming and costly, but this task can be simplified by high level languages and would even better be automated by parallelizing tools and compilers. The definition of HPF (High Performance Fortran, based on data parallel model) and OpenMP (based on shared memory parallel model) standards has offered great opportunity in this respect. Both provide simple and clear interfaces to language like FORTRAN and simplify many tedious tasks encountered in writing message passing programs. In our study, we implemented the parallel versions of the NAS Benchmarks with HPF and OpenMP directives. Comparison of their performance with the MPI implementation and pros and cons of different approaches will be discussed along with experience of using computer-aided tools to help parallelize these benchmarks. Based on the study, potentials of applying some of the techniques to realistic aerospace applications will be presented.

Jin, H.; Frumkin, M.; Hribar, M.; Waheed, A.; Yan, J.; Saini, Subhash (Technical Monitor)

1999-01-01

152

MPI, HPF or OpenMP: A Study with the NAS Benchmarks  

NASA Technical Reports Server (NTRS)

Porting applications to new high performance parallel and distributed platforms is a challenging task. Writing parallel code by hand is time consuming and costly, but the task can be simplified by high level languages and would even better be automated by parallelizing tools and compilers. The definition of HPF (High Performance Fortran, based on data parallel model) and OpenMP (based on shared memory parallel model) standards has offered great opportunity in this respect. Both provide simple and clear interfaces to language like FORTRAN and simplify many tedious tasks encountered in writing message passing programs. In our study we implemented the parallel versions of the NAS Benchmarks with HPF and OpenMP directives. Comparison of their performance with the MPI implementation and pros and cons of different approaches will be discussed along with experience of using computer-aided tools to help parallelize these benchmarks. Based on the study,potentials of applying some of the techniques to realistic aerospace applications will be presented

Jin, Hao-Qiang; Frumkin, Michael; Hribar, Michelle; Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

1999-01-01

153

Improvement of Sealing Performance for Nas Battery by a Surface Modification Process  

NASA Astrophysics Data System (ADS)

A gradient film of Na-beta-Al2O3 has been fabricated by a gas-solid reaction method to improve the sealing performance for the Na/S battery. The effect of the substrate surface pre-treatment methods on the thickness of the gradient films and the thermophysical characteristics of the gradient films have been systematically studied. It shows that the pre-treatment method on the surface of the alpha-Al2O3 has a great influence on the thickness of the film. The substrate pre-treated by MgCO3 could react with alpha-Al2O3, accompanied by the generation of spinel MgAl2O4, which could promote the formation of the Na-beta-Al2O3 film, resulting in the thickness of the Na-beta-Al2O3 film as thick as 100?m. The thermal shock resistance and thermal stability of the films were also satisfactory. The constituent of the gradient film was unchanged after thermal shock for 100 times. No micro-crack was observed on the film after heating the sample at 350 °C for 100h. The interfaces between the glass and substrates have also been analyzed.

Zhang, Gaoxiao; Wen, Zhaoyin; Wu, Xiangwei; Ma, Guoqiang

2013-07-01

154

Performance Characteristics of Hybrid MPI/OpenMP Implementations of NAS Parallel Benchmarks SP and BT on Large-scale Multicore Clusters  

E-print Network

}@cse.tamu.edu Abstract The NAS Parallel Benchmarks (NPB) are well-known applications with fixed algorithms for evaluating of the hybrid SP and BT. Keywords Performance characteristics, Hybrid MPI/OpenMP, NAS Parallel benchmarks Benchmarks (NPB) [1, 2] are well-known applications with fixed algorithms for evaluating parallel systems

155

Performance of BLAS 3, FFTs and NAS Parallel Benchmarks on Cray T3D  

NASA Technical Reports Server (NTRS)

Recently, a Cray T3D Emulator has been made available on the Cray Y-MP and C90 computers. The Pittsburgh Supercomputer Center has acquired a CRAY T3D system and many other centers like Jet Propulsion Laboratory (JPL) will have it by the end of 1994. The Cray T3D system is the firstphase system in Cray Research, Inc.'s (CRI) three-phase massively parallel processing (MPP) program. This system features a heterogeneous architecture that closely couples DEC's ALPHA microprocessors and CRI's parallel-vector technology, i.e. the Cray Y-MP and Cray C90. The Cray T3D Emulator will give prospective users a valuable experience in developing high performance applications on the MPP system. This emulator runs programs written in CRI's MPP Fortran programming model (data sharing and work sharing) or Parallel Virtual Machine (PVM) programming model. It will help the users to study data layout, data locality, and data reference patterns thereby providing feedback which will enable one to write more efficient parallel codes. An overview of the Cray T3D hardware, software, and three of its available programming models is presented.The Cray Fortran Programming Model comprising (a) Data Sharing, (b) Worksharing and (c) Message Passing, will be discussed with examples. We have also implemented distributed BLAS 3 (matrix-matrix multiplication) in data parallel model (using only CSHIFT); worksharing model using block distribution and collapsed distribution; and message passing model using PVM. We have also implemented 2D and 3D FFTs for radix-2 using PVM. The performance of NAS Parallel 'Benchmarks (NPB) on CRAY T3D will be compared with other highly parallel systems such as CM-5, Paragon, C90 etc.

Saini, Subhash; Simon, Horst D.; Cooper, D. M. (Technical Monitor)

1994-01-01

156

1.3 ?m emitting GaInNAs/GaAs quantum well resonant cavity LEDs  

NASA Astrophysics Data System (ADS)

The electrical and optical characteristics of a set of MBE-grown 1.3 ?m emitting GaInNAs/GaAs quantum well (QW) resonant cavity light-emitting diodes (RCLEDs) have been analyzed as a function of the growth temperature of the distributed Bragg reflector (DBR) and the contact alloying. The RCLEDs consist of a ?-long microcavity delimited on one side by an 8-pair AlAs/GaAs DBR and on the opposite side by a metallic mirror, with the QW located at one of the antinodes of the standing wave. The structures are designed for extraction of the light through the substrate. Room-temperature electroluminescence at 1.3 ?m is demonstrated with 38% In and 1.3% N in the quantum well. It is found that the RCLEDs with the DBR grown at the lowest temperature of 670 °C show a lower differential slope efficiency and degraded current-voltage characteristics, i.e. higher ideality factor, lower shunt resistance and lower threshold voltage. This degradation can be explained to arise from the higher roughness observed in the DBRs grown at 670 °C, which likely enhance the formation of point defects and compositional inhomogeneities in the quantum well. Alloying of the ohmic contacts also results in a widening of the electroluminescence emission, probably due to the degradation of the top metallic mirror sharpness caused by the diffusion of the metal into the GaAs. The best results in terms of differential slope efficiency and electrical characteristics are obtained when the DBRs are grown at 750 °C and the contacts are left non-alloyed.

Montes, M.; Guzmán, A.; Trampert, A.; Hierro, A.

2010-04-01

157

On Ensino de Astronomia nas Cidades de Ribeirão Pires e Rio Grande da Serra  

NASA Astrophysics Data System (ADS)

Apesar da astronomia ser um dos temas indicados pelos Parâmetros Curriculares Nacionais, observa-se que poucas mudanças ocorreram desde a implementação do mesmo em sala de aula. A presente pesquisa diz respeito sobre como os tópicos de astronomia estão sendo abordados pelos professores no ensino médio. Optou-se por aplicar um questionário com os professores que ministram a disciplina de física. Os mesmos trabalham em escolas estaduais situadas nas cidades de Ribeirão Pires e Rio Grande da Serra, ambas subordinadas a Diretoria de Ensino de Mauá, no Estado de São Paulo. O questionário foi aplicado durante o 2° semestre de 2006. Até o momento os resultados são preliminares. Dos 82,0% dos professores que responderam ao questionário no município de Rio Grande da Serra, 66,7% não aplicaram nenhum tópico de astronomia, 77,8% não utilizaram qualquer tipo de programa computacional, 66,7% não utilizaram laboratório, que 77,8% nunca levaram os alunos a museus e ou planetários e que 66,7% não indicaram qualquer tipo de revista ou livro sobre astronomia aos seus alunos. No município de Ribeirão Pires, 53,3% dos professores responderam ao questionário, destes 75,0% não aplicaram nenhum tópico de astronomia, 93,8% não utilizaram qualquer tipo de programa computacional, 75,0% não utilizaram laboratório, 81,3% nunca levaram os alunos a museus e ou planetário e 56,3% não indicaram qualquer tipo de revista ou livro sobre astronomia ao seus alunos. Apesar da maioria dos professores reconhecerem que o conteúdo de astronomia influi na formação do jovem, os mesmos não incluem o tema em seus planejamentos escolares.

Faria, R. Z.; Voelzke, M. R.

2007-08-01

158

Photoconductivity and photoluminescence under bias in GaInNAs/GaAs MQW p-i-n structures  

PubMed Central

The low temperature photoluminescence under bias (PLb) and the photoconductivity (PC) of a p-i-n GaInNAs/GaAs multiple quantum well sample have been investigated. Under optical excitation with photons of energy greater than the GaAs bandgap, PC and PLb results show a number of step-like increases when the sample is reverse biased. The nature of these steps, which depends upon the temperature, exciting wavelength and intensity and the number of quantum wells (QWs) in the device, is explained in terms of thermionic emission and negative charge accumulation due to the low confinement of holes in GaInNAs QWs. At high temperature, thermal escape from the wells becomes much more dominant and the steps smear out. PMID:23021540

2012-01-01

159

NASA's UAS Integration into the NAS: A Report on the Human Systems Integration Phase 1 Simulation Activities  

NASA Technical Reports Server (NTRS)

In 2011 the National Aeronautics and Space Administration (NASA) began a five-year Project to address the technical barriers related to routine access of Unmanned Aerial Systems (UAS) in the National Airspace System (NAS). Planned in two phases, the goal of the first phase was to lay the foundations for the Project by identifying those barriers and key issues to be addressed to achieve integration. Phase 1 activities were completed two years into the five-year Project. The purpose of this paper is to review activities within the Human Systems Integration (HSI) subproject in Phase 1 toward its two objectives: 1) develop GCS guidelines for routine UAS access to the NAS, and 2) develop a prototype display suite within an existing Ground Control Station (GCS). The first objective directly addresses a critical barrier for UAS integration into the NAS - a lack of GCS design standards or requirements. First, the paper describes the initial development of a prototype GCS display suite and supporting simulation software capabilities. Then, three simulation experiments utilizing this simulation architecture are summarized. The first experiment sought to determine a baseline performance of UAS pilots operating in civil airspace under current instrument flight rules for manned aircraft. The second experiment examined the effect of currently employed UAS contingency procedures on Air Traffic Control (ATC) participants. The third experiment compared three GCS command and control interfaces on UAS pilot response times in compliance with ATC clearances. The authors discuss how the results of these and future simulation and flight-testing activities contribute to the development of GCS guidelines to support the safe integration of UAS into the NAS. Finally, the planned activities for Phase 2, including an integrated human-in-the-loop simulation and two flight tests are briefly described.

Fern, Lisa; Rorie, R. Conrad; Shively, R. Jay

2014-01-01

160

Nitrogen-concentration control in GaNAs/AlGaAs quantum wells using nitrogen ?-doping technique  

SciTech Connect

GaNAs/Al{sub 0.35}Ga{sub 0.65}As multiple quantum wells (MQWs) with nitrogen ?-doping were fabricated on GaAs (100) substrates by plasma-assisted molecular beam epitaxy. High controllability of nitrogen-concentrations in the MQWs was achieved by tuning nitrogen ?-doping time. The maximum nitrogen concentration in the MQWs was 2.8%. The MQWs exhibit intense, narrow photoluminescence emission.

Mano, Takaaki; Jo, Masafumi; Kuroda, Takashi; Noda, Takeshi; Sugimoto, Yoshimasa; Sakuma, Yoshiki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Elborg, Martin; Sakoda, Kazuaki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan and Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan)

2014-05-15

161

Nitrogen-concentration control in GaNAs/AlGaAs quantum wells using nitrogen δ-doping technique  

NASA Astrophysics Data System (ADS)

GaNAs/Al0.35Ga0.65As multiple quantum wells (MQWs) with nitrogen ?-doping were fabricated on GaAs (100) substrates by plasma-assisted molecular beam epitaxy. High controllability of nitrogen-concentrations in the MQWs was achieved by tuning nitrogen ?-doping time. The maximum nitrogen concentration in the MQWs was 2.8%. The MQWs exhibit intense, narrow photoluminescence emission.

Mano, Takaaki; Jo, Masafumi; Kuroda, Takashi; Elborg, Martin; Noda, Takeshi; Sugimoto, Yoshimasa; Sakuma, Yoshiki; Sakoda, Kazuaki

2014-05-01

162

1.55 {mu}m GaAs/GaNAsSb/GaAs optical waveguides grown by radio frequency nitrogen plasma-assisted molecular beam epitaxy  

SciTech Connect

We demonstrate a 1.55 {mu}m GaAs/GaNAsSb/GaAs optical waveguide grown by molecular beam epitaxy as an alternative to the AlGaAs/GaAs system. The 0.4-{mu}m-thick GaNAsSb guiding layer contains {approx}3.5% of N and 9% of Sb, resulting in optical band gap of 0.88 eV. The refractive index of the GaNAsSb layer was measured from 800 to 1700 nm. The GaNAsSb layer has a refractive index value of 3.42 at 1.55 {mu}m wavelength. The propagation loss measured using the Fabry-Perot resonance method was found to be affected by nitrogen-related defect absorption.

Tan, K. H.; Yoon, S. F.; Loke, W. K.; Wicaksono, S.; Xu, Z.; Ng, T. K.; Lew, K. L. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Saadsaoud, N.; Zegaoui, M.; Decoster, D. [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille BP 60069, 59652 Villeneuve d'Ascq Cedex (France); Chazelas, J. [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)

2008-03-17

163

1.3- m GaNAsSb–GaAs UTC-Photodetectors for 10Gigabit Ethernet Links  

Microsoft Academic Search

We report on 10 gigabit Ethernet (IEEE 802.3ae) fiber-optic transmission at 1.3 mum wavelengh utilizing high-speed GaNAsSb uni-travelling-carrier photodetectors (PDs) grown on GaAs substrate. With an optical bandgap of ~0.88 eV, the PDs are suitable for near-infrared operation up to wavelengths of about 1380 nm. The dc responsivity and 3-dB cut-off frequency of the non-antireflection-coated PD at 1.3-mu m wavelength

S. Fedderwitz; A. Stohr; K. H. Tan; S. F. Yoon; M. Weiss; A. Poloczek; W. K. Loke; S. Wicaksono; T. K. Ng; V. Rymanov; A. Patra; E. Tangdiongga; D. Jager

2009-01-01

164

Remotely Operated Aircraft (ROA) Impact on the National Airspace System (NAS) Work Package, 2005: Composite Report on FAA Flight Plan and Operational Evaluation Plan. Version 7.0  

NASA Technical Reports Server (NTRS)

The purpose of this document is to present the findings that resulted from a high-level analysis and evaluation of the following documents: (1) The OEP (Operational Evolution Plan) Version 7 -- a 10-year plan for operational improvements to increase capacity and efficiency in U.S. air travel and transport and other use of domestic airspace. The OEP is the FAA commitment to operational improvements. It is outcome driven, with clear lines of accountability within FAA organizations. The OEP concentrates on operational solutions and integrates safety, certification, procedures, staffing, equipment, avionics and research; (2) The Draft Flight Plan 2006 through 2010 -- a multi-year strategic effort, setting a course for the FAA through 2001, to provide the safest and most efficient air transportation system in the world; (3) The NAS System Architecture Version 5 -- a blueprint for modernizing the NAS and improving NAS services and capabilities through the year 2015; and (4) The NAS-SR-1000 System Requirements Specification (NASSRS) -- a compilation of requirements which describe the operational capabilities for the NAS. The analysis is particularly focused on examining the documents for relevance to existing and/or planned future UAV operations. The evaluation specifically focuses on potential factors that could materially affect the development of a commercial ROA industry, such as: (1) Design limitations of the CNS/ATM system, (2) Human limitations, The information presented was taken from program specifications or program office lead personnel.

2005-01-01

165

Three of Four GlnR Binding Sites Are Essential for GlnR-Mediated Activation of Transcription of the Amycolatopsis mediterranei nas Operon  

PubMed Central

In Amycolatopsis mediterranei U32, genes responsible for nitrate assimilation formed one operon, nasACKBDEF, whose transcription is induced by the addition of nitrate. Here, we characterized GlnR as a direct transcriptional activator for the nas operon. The GlnR-protected DNA sequences in the promoter region of the nas operon were characterized by DNase I footprinting assay, the previously deduced Streptomyces coelicolor double 22-bp GlnR binding consensus sequences comprising a1, b1, a2, and b2 sites were identified, and the sites were then mutated individually to test their roles in both the binding of GlnR in vitro and the GlnR-mediated transcriptional activation in vivo. The results clearly showed that only three GlnR binding sites (a1, b1, and b2 sites) were required by GlnR for its specific binding to the nas promoter region and efficient activation of the transcription of the nas operon in U32, while the a2 site seemed unnecessary. PMID:23543714

Wang, Ying; Wang, Jing-Zhi; Shao, Zhi-Hui; Yuan, Hua; Lu, Yin-Hua; Jiang, Wei-Hong

2013-01-01

166

Electronic and optical structure of 1.55 ?m emitting GaInNAs quantum dots on different substrates  

NASA Astrophysics Data System (ADS)

We present a theoretical study which compares the electronic and optical properties of GaInNAs quantum dots (QD) with dilute amount of nitrogen (< 4%) on two different substrates, GaAs (001) and InP (001). The calculations are based on a 10 band k.p band-anti-crossing (BAC) Hamiltonian, incorporating valence, conduction and nitrogen-induced bands. We show that 1.55 ?m emission can be achieved on both substrates through appropriate tailoring of the QD size. On GaAs, the dominant dipole matrix element is the of the in-plane light polarization, whereas on InP substrate, the dominant component is of the perpendicular light polarization. Our results also identify the different In and N QD compositions required for long-wavelength emission on both material substrates.

Tomi?, Stanko

2010-01-01

167

Origin of radiative recombination and manifestations of localization effects in GaAs/GaNAs core/shell nanowires  

NASA Astrophysics Data System (ADS)

Radiative carrier recombination processes in GaAs/GaNAs core/shell nanowires grown by molecular beam epitaxy on a Si substrate are systematically investigated by employing micro-photoluminescence (?-PL) and ?-PL excitation (?-PLE) measurements complemented by time-resolved PL spectroscopy. At low temperatures, alloy disorder is found to cause localization of photo-excited carriers leading to predominance of optical transitions from localized excitons (LE). Some of the local fluctuations in N composition are suggested to lead to strongly localized three-dimensional confining potential equivalent to that for quantum dots, based on the observation of sharp and discrete PL lines within the LE contour. The localization effects are found to have minor influence on PL spectra at room temperature due to thermal activation of the localized excitons to extended states. Under these conditions, photo-excited carrier lifetime is found to be governed by non-radiative recombination via surface states which is somewhat suppressed upon N incorporation.

Chen, S. L.; Filippov, S.; Ishikawa, Fumitaro; Chen, W. M.; Buyanova, I. A.

2014-12-01

168

Transmission electron microscopy study of GaInNAs(Sb) thin films grown by atomic hydrogen-assisted molecular beam epitaxy  

SciTech Connect

The quaternary GaInNAs is a promising material system for use in next generation multijunction photovoltaic devices. We have investigated the effect of introducing antimony on the growth by using transmission electron microscopy and energy dispersive x-ray (EDX) spectroscopy. Two-dimensional growth was observed in GaInNAs films with striation features associated with compositional fluctuation and nanometer scale elemental segregation on the growth front. On the contrary, GaInNAsSb films exhibit uniform contrast throughout. EDX profile indicates uniform compositional distribution, as antimony atoms suppress the surface mobilites of adatoms resulting in a lower probability to generate the favored bonds, such as Ga-N and In-As.

Oshima, R. [Research Center for Advanced Science and Technology (RCAST), University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Huang, J. Y.; Ponce, F. A. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Miyashita, N.; Okada, Y. [Research Center for Advanced Science and Technology (RCAST), University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Matsubara, K. [National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

2011-11-07

169

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 481488. Crystal Basis Model of the Genetic Code  

E-print Network

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 481­488. Crystal features of a model of genetic code based on the crystal basis of Uq0(sl(2)sl(2)) is presented (Ala), Arginine (Arg), Asparagine (Asn), Aspartic acid (Asp), Cysteine (Cys), Glutamine (Gln), Glutamic

Popovych, Roman

170

THE NAS PARALLEL BENCHMARKS D. H. Bailey1, E. Barszcz1, J. T. Barton1, D. S. Browning2, R. L. Carter, L.  

E-print Network

THE NAS PARALLEL BENCHMARKS D. H. Bailey1, E. Barszcz1, J. T. Barton1, D. S. Browning2, R. L evaluation of highly parallel supercomputers. These benchmarks con- sist of ve \\parallel kernel" benchmarks to the computational aerophysics community on many currently available parallel systems. Benchmarking and performance

Bailey, David H.

171

Performance characteristics of hybrid MPI\\/OpenMP implementations of NAS parallel benchmarks SP and BT on large-scale multicore supercomputers  

Microsoft Academic Search

The NAS Parallel Benchmarks (NPB) are well-known applications with the fixed algorithms for evaluating parallel systems and tools. Multicore supercomputers provide a natural programming paradigm for hybrid programs, whereby OpenMP can be used with the data sharing with the multicores that comprise a node and MPI can be used with the communication between nodes. In this paper, we use SP

Xingfu Wu; Valerie E. Taylor

2011-01-01

172

GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 ?m operation  

PubMed Central

Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This study investigates the prospects for a Hellish VCSOA based on GaInNAs/GaAs material for operation in the 1.3-?m wavelength range. Hellish VCSOAs have increased functionality, and use undoped distributed Bragg reflectors; and this coupled with direct injection into the active region is expected to yield improvements in the gain and bandwidth. The design of the Hellish VCSOA is based on the transfer matrix method and the optical field distribution within the structure, where the determination of the position of quantum wells is crucial. A full assessment of Hellish VCSOAs has been performed in a device with eleven layers of Ga0.35In0.65N0.02As0.08/GaAs quantum wells (QWs) in the active region. It was characterised through I-V, L-V and by spectral photoluminescence, electroluminescence and electro-photoluminescence as a function of temperature and applied bias. Cavity resonance and gain peak curves have been calculated at different temperatures. Good agreement between experimental and theoretical results has been obtained. PMID:21711630

2011-01-01

173

GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 ?m operation.  

PubMed

Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This study investigates the prospects for a Hellish VCSOA based on GaInNAs/GaAs material for operation in the 1.3-?m wavelength range. Hellish VCSOAs have increased functionality, and use undoped distributed Bragg reflectors; and this coupled with direct injection into the active region is expected to yield improvements in the gain and bandwidth. The design of the Hellish VCSOA is based on the transfer matrix method and the optical field distribution within the structure, where the determination of the position of quantum wells is crucial. A full assessment of Hellish VCSOAs has been performed in a device with eleven layers of Ga0.35In0.65N0.02As0.08/GaAs quantum wells (QWs) in the active region. It was characterised through I-V, L-V and by spectral photoluminescence, electroluminescence and electro-photoluminescence as a function of temperature and applied bias. Cavity resonance and gain peak curves have been calculated at different temperatures. Good agreement between experimental and theoretical results has been obtained. PMID:21711630

Chaqmaqchee, Faten Adel Ismail; Mazzucato, Simone; Oduncuoglu, Murat; Balkan, Naci; Sun, Yun; Gunes, Mustafa; Hugues, Maxime; Hopkinson, Mark

2011-01-01

174

Study of a 1?eV GaNAsSb photovoltaic cell grown on a silicon substrate  

SciTech Connect

We report the performance of a 1?eV GaNAsSb photovoltaic cell grown on a Si substrate with a SiGe graded buffer grown using molecular beam epitaxy. For comparison, the performance of a similar 1?eV GaN{sub 0.018}As{sub 0.897}Sb{sub 0.085} photovoltaic cell grown on a GaAs substrate was also reported. Both devices were in situ annealed at 700?°C for 5?min, and a significant performance improvement over our previous result was observed. The device on the GaAs substrate showed a low open circuit voltage (V{sub OC}) of 0.42?V and a short circuit current density (J{sub SC}) of 23.4?mA/cm{sup 2} while the device on the Si substrate showed a V{sub OC} of 0.39?V and a J{sub SC} of 21.3?mA/cm{sup 2}. Both devices delivered a quantum efficiency of 50%–55% without any anti-reflection coating.

Tan, K. H.; Loke, W. K.; Wicaksono, S.; Li, D.; Leong, Y. R.; Yoon, S. F. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)] [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Sharma, P.; Milakovich, T.; Bulsara, M. T.; Fitzgerald, E. A. [Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States)

2014-03-10

175

The solution of linear systems of equations with a structural analysis code on the NAS CRAY-2  

NASA Technical Reports Server (NTRS)

Two methods for solving linear systems of equations on the NAS Cray-2 are described. One is a direct method; the other is an iterative method. Both methods exploit the architecture of the Cray-2, particularly the vectorization, and are aimed at structural analysis applications. To demonstrate and evaluate the methods, they were installed in a finite element structural analysis code denoted the Computational Structural Mechanics (CSM) Testbed. A description of the techniques used to integrate the two solvers into the Testbed is given. Storage schemes, memory requirements, operation counts, and reformatting procedures are discussed. Finally, results from the new methods are compared with results from the initial Testbed sparse Choleski equation solver for three structural analysis problems. The new direct solvers described achieve the highest computational rates of the methods compared. The new iterative methods are not able to achieve as high computation rates as the vectorized direct solvers but are best for well conditioned problems which require fewer iterations to converge to the solution.

Poole, Eugene L.; Overman, Andrea L.

1988-01-01

176

The NAS parallel benchmarks  

NASA Technical Reports Server (NTRS)

A new set of benchmarks was developed for the performance evaluation of highly parallel supercomputers. These benchmarks consist of a set of kernels, the 'Parallel Kernels,' and a simulated application benchmark. Together they mimic the computation and data movement characteristics of large scale computational fluid dynamics (CFD) applications. The principal distinguishing feature of these benchmarks is their 'pencil and paper' specification - all details of these benchmarks are specified only algorithmically. In this way many of the difficulties associated with conventional benchmarking approaches on highly parallel systems are avoided.

Bailey, David (editor); Barton, John (editor); Lasinski, Thomas (editor); Simon, Horst (editor)

1993-01-01

177

Molecular beam epitaxy of GaNAs alloys with high As content for potential photoanode applications in hydrogen production  

SciTech Connect

The authors have succeeded in growing GaN1?xAsx alloys over a large composition range (0 < x < 0.8) by plasma-assisted molecular beam epitaxy. The enhanced incorporation of As was achieved by growing the films with high As{sub 2} flux at low (as low as 100 C) growth temperatures, which is much below the normal GaN growth temperature range. Using x-ray and transmission electron microscopy, they found that the GaNAs alloys with high As content x > 0.17 are amorphous. Optical absorption measurements together with x-ray absorption and emission spectroscopy results reveal a continuous gradual decrease in band gap from -3.4 to < 1 eV with increasing As content. The energy gap reaches its minimum of -0.8 eV at x - 0.8. The composition dependence of the band gap of the crystalline GaN{sub 1?x}As{sub x} alloys follows the prediction of the band anticrossing model (BAC). However, our measured band gap of amorphous GaN{sub 1?x}As{sub x} with 0.3 < x < 0.8 are larger than that predicted by BAC. The results seem to indicate that for this composition range the amorphous GaN{sub 1?x}As{sub x} alloys have short-range ordering that resembles random crystalline GaN{sub 1?x}As{sub x} alloys. They have demonstrated the possibility of the growth of amorphous GaN{sub 1?x}As{sub x} layers with variable As content on glass substrates

Novikov, S. V.; Staddon, C. R.; Foxon, C. T.; Yu, K. M.; Broesler, R.; Hawkridge, M.; Liliental-Weber, Z.; Walukiewicz, W.; Denlinger, J.; Demchenko, I.

2009-10-06

178

Contactless electroreflectance study of band bending in Be-doped GaInNAs/GaAs quantum wells: The origin of photoluminescence enhancement  

NASA Astrophysics Data System (ADS)

Contactless electroreflectance (CER) has been applied to study band bending in Be-doped GaInNAs/GaAs quantum wells (QWs). It has been shown that (i) the sign of GaAs-related CER signal changes from positive to negative due to Be-doping and (ii) QW-related CER resonances disappear for Be-doped QWs whereas they are clearly observed for un-doped QWs. The two observations indicate a Be-related shift in the Fermi level above the hole levels in the QW region, i.e., the change in band bending in this system. The results point out that the experimentally-observed enhancement in QW photoluminescence upon Be-doping is associated with a better collection/confinement of photogenerated carriers by the Be-doped GaInNAs QW.

Kudrawiec, R.; Gladysiewicz, M.; Misiewicz, J.; Korpijärvi, V.-M.; Pakarinen, J.; Puustinen, J.; Laukkanen, P.; Laakso, A.; Guina, M.; Dumitrescu, M.; Pessa, M.

2010-07-01

179

Weather Requirements and Procedures for Step 1: High Altitude Long Endurance (HALE) Unmanned Aircraft System (UAS) Flight Operations in the National Air Space (NAS)  

NASA Technical Reports Server (NTRS)

This cover sheet is for version 2 of the weather requirements document along with Appendix A. The purpose of the requirements document was to identify and to list the weather functional requirements needed to achieve the Access 5 vision of "operating High Altitude, Long Endurance (HALE) Unmanned Aircraft Systems (UAS) routinely, safely, and reliably in the National Airspace System (NAS) for Step 1." A discussion of the Federal Aviation Administration (FAA) references and related policies, procedures, and standards is provided as basis for the recommendations supported within this document. Additional procedures and reference documentation related to weather functional requirements is also provided for background. The functional requirements and related information are to be proposed to the FAA and various standards organizations for consideration and approval. The appendix was designed to show that sources of flight weather information are readily available to UAS pilots conducting missions in the NAS. All weather information for this presentation was obtained from the public internet.

2007-01-01

180

A quantitative study of radiative, Auger, and defect related recombination processes in 1.3-?m GaInNAs-based quantum-well lasers  

Microsoft Academic Search

By measuring the spontaneous emission (SE) from normally operating ?1.3-?m GaInNAs-GaAs-based lasers we have quantitatively determined the variation of each of the current paths present in the devices as a function of temperature from 130 K to 370 K. From the SE measurements we determine how the current I close to threshold, varies as a function of carrier density n,

Robin Fehse; Stanko Tomic; Alfred R. Adams; Stephen John Sweeney; E. P. O'Reilly; A. Andreev; H. Riechert

2002-01-01

181

Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project, UAS Control and Non-Payload Communication System Phase-1 Flight Test Results  

NASA Technical Reports Server (NTRS)

NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication (CNPC) system prototype radio, operating on recently allocated UAS frequency spectrum bands. This prototype radio is being used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current status of the prototype radio development, and results from phase 1 flight tests conducted during 2013.

Griner, James H.

2014-01-01

182

Identification of nitrogen- and host-related deep-level traps in n-type GaNAs and their evolution upon annealing  

SciTech Connect

Deep level traps in as-grown and annealed n-GaNAs layers (doped with Si) of various nitrogen concentrations (N?=?0.2%, 0.4%, 0.8%, and 1.2%) were investigated by deep level transient spectroscopy. In addition, optical properties of GaNAs layers were studied by photoluminescence and contactless electroreflectance. The identification of N- and host-related traps has been performed on the basis of band gap diagram [Kudrawiec, Appl. Phys. Lett. 101, 082109 (2012)], which assumes that the activation energy of electron traps of the same microscopic nature decreases with the rise of nitrogen concentration in accordance with the N-related shift of the conduction band towards trap levels. The application of this diagram has allowed to investigate the evolution of donor traps in GaNAs upon annealing. In general, it was observed that the concentration of N- and host-related traps decreases after annealing and PL improves very significantly. However, it was also observed that some traps are generated due to annealing. It explains why the annealing conditions have to be carefully optimized for this material system.

Gelczuk, ?., E-mail: lukasz.gelczuk@pwr.edu.pl [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Kudrawiec, R., E-mail: robert.kudrawiec@pwr.edu.pl [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Henini, M. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2014-07-07

183

[Various ecological problems related to mining and processing of serpentine. Evaluation of non-occupational exposure of the population of Nas?awice to fibrous mineral dust].  

PubMed

Non-occupational exposure of the population living in the vicinity of the serpentine mining and processing mill in Nas?awice was assessed. The evaluation was based on the phase analysis and determination of respirable mineral fibres content in the samples of dust fall and soil in the fields nearby the mine, as well as on the in-door and out-door measurements of airborne fibres concentration. All soil samples contained antigorite--a mineral the structure of which is close to that of chrysotile asbestos add exhibiting high biological aggressiveness. The respirable mineral fibres content in the dust fall-out and in the soil ranged from 98,000 to 480,000 per 1 mg and from 48,000 to 122,000 per 1 mg, respectively, whereas the airborne concentrations were from 2 to 1540 fibres/l (outdoor) and from 4 to 7 fibres/l (indoor). The fall of dust in the years 1989-1990, recorded at all measuring points, exceeded 200,000 kg/km2 yearly (admissible value). The airborne concentrations of respirable mineral fibres were also higher than the admissible value (1 fibre/l of the air). The results obtained indicate that the exposure of the population in Nas?awice to mineral fibrous dusts has significantly exceeded to maximum admissible concentrations established for non-occupational exposure. PMID:1328808

Wo?niak, H; Wiecek, E; Dobrucka, D; Pelc, W; Bielichowska-Cybula, G; Król, M; Opalska, B

1992-01-01

184

Instituto Nacional de Pesquisas Espaciais Exame para o curso de ps-graduao em Astrofsica  

E-print Network

for Extraterrestrial Intelligence), afirmava que o grande radiotelescópio de Arecibo, em Porto Rico, "pode detectar um magnético? b) A que aceleração ele é submetido? #12;6. Frank Drake, um dos criadores do projeto SETI (Search

185

Recent results of plasma research activities at the Instituto de Pesquisas Espaciais  

NASA Astrophysics Data System (ADS)

Results of experiments performed at the Institute for Space Research (INPE) are reported. An enrichment of 390 percent of carbon isotopes was achieved in the plasma centrifuge. The role of ion-acoustic turbulence in the formation of double layers was experimentally investigated. The turbulent spectrum was measured and agrees quite well with the prediction of the modified Kadomtsev renormalized theory. The characteristics of the gyrotron that is being built at INPE and new techniques for gyrotron design are discussed. Theoretical results on the generalized Spitzer-Haerm problem, current drive in the start-up of tokamaks, and quasilinear theory of beat-wave current drive are also presented.

Barroso, J. J.; Bittencourt, J. A.; Dallaqua, R. S.; Delbosco, E.; Ferreira, A.; Ferreira, J. L.; Galvao, G. P.; Galvao, R. M. O.; Ludwig, G. O.; Montes, A.

1987-09-01

186

MINISTRIO DA CINCIA E TECNOLOGIA INSTITUTO NACIONAL DE PESQUISAS ESPACIAIS INPE  

E-print Network

.4. Revistas Nacionais ­ QUALIS C OU SEM QUALIS (7)................................... 24 7. LIVROS............................................................................................................ 25 7.1. Livros Internacionais C/ ISBN (4)................................................................ 25 7.2. Livros Nacionais C/ ISBN (14

187

Optimal Blast Condition for the Inner Surface of Mass Produced NAS Battery Cylindrical Aluminum Cell Containers as Pretreatment of Thermal Spraying  

NASA Astrophysics Data System (ADS)

The relationship between roughness caused by blasting and adhesion of spray coatings on aluminum container substrates was studied through various experiments as part of measures for improving the adhesion of the 75mass%Cr-Fe alloy plasma spray coating for sulfi dation corrosion resistance, which is applied on the inner surface of cylindrical Al containers of high-temperature type NAS batteries. Surface roughness of ?mRa2.8 - 7.3 was acquired by using Al2O3 particle size #100 (212 - 75?m) to #46 (600 - 250?m) grit. In order to achieve uniform roughness and a clean surface, a combination of blasting when the nozzle was being inserted from the top of the container, and air blowing when the nozzle was being removed was done. It was determined that when Al2O3 particles of size #100 grit was used, a good anchoring shape was formed throughout with a roughened surface of ?mRa 2.8. When the internal surface of 3000 Al cylindrical containers were continually blasted using particle size #100 grit, the initial surface roughness of ?mRa3.7 - 3.9 only deteriorated to about ?mRa2.6. A 75mass%Cr-Fe alloy spray coating was applied to the Al cylindrical containers that were roughened using particle size #100 grit. This coating showed cracks by a bending test, but no peeling occurred. This coating was examined by a tensile strength test and showed good adhesion at 64 - 66 MPa. Through experiments, it was proven that spray coatings formed on the Al cylindrical containers after receiving optimal blasting with particle size #100 grit had good adhesion and corrosion resistance after being used for NAS batteries that stored electrical power for about nine years.

Ando, Takashi; Harada, Yoshio

188

Nitrogen-related changes in exciton localization and dynamics in GaInNAs/GaAs quantum wells grown by metalorganic vapor phase epitaxy  

NASA Astrophysics Data System (ADS)

In this work, we show the results of low-temperature photoluminescence (PL), time-resolved photoluminescence, and photoreflectance (PR) investigations, performed on a series of three Ga0.64In0.34As1- x N x /GaAs single quantum wells (SQW) grown by metalorganic vapor phase epitaxy with the nitrogen content of 0, 0.5, and 0.8 %. Comparing the PL and PR data, we show that at low excitation intensity and temperature, the radiative recombination occurs via localizing centers (LCs) in all samples. The excitation intensity-dependent PL measurements combined with theoretical modeling of hopping excitons in this system allow us to provide quantitative information on the disorder parameters describing population of LCs. It has been found that the average energy of LCs increases about two times and simultaneously the number of LCs increases about 10 and 20 times after the incorporation of 0.5 and 0.8 % of nitrogen, respectively. The value of average localization energy ? 0 determined for N-containing samples (~6-7 meV) is in the range typical for dilute nitride QWs grown by molecular beam epitaxy (MBE). On the other hand, the "effective" concentration of LCs seems to be higher than for GaInNAs/GaAs QW grown by MBE. The dramatic increase in localizing centers also affects the PL dynamics. Observed PL decay time dispersion is much stronger in GaInNAs SQW than in nitrogen-free SQW. The change in PL dynamic is very well reproduced by model of hopping excitons.

Baranowski, M.; Kudrawiec, R.; Misiewicz, J.; Hammar, M.

2015-02-01

189

Investigation of the seasonal and local time variations of the high-altitude sporadic Na layer (Nas) formation and the associated midlatitude descending E layer (Es) in lower E region  

NASA Astrophysics Data System (ADS)

studies have suggested that the major reservoir for the sporadic sodium layer (Nas) above 95 km in altitude is likely the sodium ion (Na+) within the sporadic E layer (Es) in the lower E region. However, theoretical and laboratory works have demonstrated that the metal ion's neutralization process is quite difficult above 100 km, while intensive neutral metal layers are consistently observed in the lower E region between 100 km and 125 km. In this paper, the multiyear observations of a Na lidar and an ionosonde at Utah State University (41.7°N, 111.8°W) and the nearby Bear Lake Observatory (41.9°N, 111.4°W) are utilized to understand their seasonal and local time variations. The comparison study between this set of the Nas and the nocturnal Nas observations in Beijing China (40.2°N, 116.1°E) reveals similar variations, but major differences are also noticed. To investigate the mechanism of these variations, the Hamburg Model of the Neutral and Ionized Atmosphere and the Climatological Tidal Model of the Thermosphere are utilized to simulate the ion vertical drift in the lower E region. The simulation shows that the lower E region is dominated by convergence of metal ions in summer, and ion diffusion prevails during winter. The tidal wind modulates the ion vertical drift speed and increases the likelihood of Es evolution at certain local times during the summer, while the tidal components of atmospheric density facilitate Nas formation by neutralizing the Na+ within the Es.

Yuan, T.; Wang, Jihong; Cai, Xuguang; Sojka, J.; Rice, D.; Oberheide, J.; Criddle, N.

2014-07-01

190

GaInNAs semiconductor disk lasers as pump sources for Tm3+ (,Ho3+ )-doped glass, crystal and fibre lasers  

NASA Astrophysics Data System (ADS)

We report the first use of a Semiconductor Disk Laser (SDL) as a pump source for ~2?m-emitting Tm3+ (,Ho3+)-doped dielectric lasers. The ~1213nm GaInNAs/GaAs SDL produces >1W of CW output power, a maximum power transfer net slope efficiency of 18.5%, and a full width half maximum wavelength tuning range of ~24nm. Free-running operation of a Tm3+-doped tellurite glass laser under 1213nm SDL pumping generated up to 60mW output power with 22.4% slope efficiency. Wavelength tunable output is also obtained from 1845 to 2043nm. Improved performance with output powers of ~200mW and a slope efficiency of ~35% are achieved by replacing the Tm3+-doped glass with a Tm3+-doped KYW active medium. Emission of a Tm3+,Ho3+-codoped tellurite glass laser is also reported with maximum output power of ~12mW and a ~7% slope efficiency. Finally, preliminary investigations of 1213nm-pumping of a Tm3+,Ho3+-codoped silica fibre laser lead to 36mW output power with ~19.3% slope efficiency.

Vetter, Sharon L.; McKnight, L. J.; Calvez, Stephane; Dawson, Martin D.; Fusari, F.; Lagatsky, Alexander A.; Sibbett, Wilson; Brown, Christian T. A.; Korpijärvi, Ville-Markus; Guina, Mircea D.; Richards, B.; Jose, G.; Jha, Animesh

2009-02-01

191

Pratt and Whitney/Boeing Engine Validation of Noise Reduction Concepts: Final Report for NASA Contract NAS3-97144, Phase 1  

NASA Technical Reports Server (NTRS)

Major airports in the world's air transportation systems face a serious problem in providing greater capacity to meet the ever increasing demands of air travel. This problem could be relieved if airports are allowed to increase their operating time, now restricted by curfews and by relaxing present limits on takeoffs and landings. The key operational issue in extending the present curfews is noise. In response to these increasing restrictive noise regulations, NASA has launched a program to validate through engine testing, noise reduction concepts and technologies that have evolved from the Advanced Subsonic Technologies (AST) Noise Reduction Program. The goal of this AST program was to develop and validate technology that reduces engine noise and improves nacelle suppression effectiveness relative to 1992 technology. Contract NAS3-97144 titled "Engine Validation of Noise Reduction Concepts" (EVNRC) was awarded to P&W on August 12, 1997 to conduct full scale noise reduction tests in two Phases on a PW4098 engine. The following Section 1.2 provides a brief description of the overall program. The remainder of this report provides a detailed documentation of Phase I of the program.

Mathews, Douglas; Bock, Larry A.; Bielak, Gerald W.; Dougherty, R. P.; Premo, John W.; Scharpf, Dan F.; Yu, Jia

2014-01-01

192

Corte nas bolsas de doutoramento  

E-print Network

pós- doutoramentos, este ano, que foi o que teve o maior número de candida- turas de sempre, há uma em curso?", questionava no Facebook da ABIC Perpétua Santos Silva, num comentário em que dizia ter sido prejudicada na sua candida- tura por causa de

Instituto de Sistemas e Robotica

193

Map of a UAV flight operation in the NAS at the JER. The initial external pilot (EP) position is at P0. The UAV is launched at the red cross position into the  

E-print Network

Map of a UAV flight operation in the NAS at the JER. The initial external pilot (EP) position is at P0. The UAV is launched at the red cross position into the launch orbit, and is then moved to the H1 holding orbit. Once the EP has moved from P0 to P1, the UAV acquires imagery over the first flight area

194

Characterization of 1.3-um wavelength GaInNAs/GaAs edge-emitting and vertical-cavity surface-emitting lasers using low temperature and high pressure  

NASA Astrophysics Data System (ADS)

By measuring the spontaneous emission from normally operating ~1.3um GaInNAs/GaAs-based lasers grown by MBE and by MOVPE we have quantitatively determined the variation of monomolecular (defect-related ~An), radiative (~Bn2) and Auger recombination (~Cn3) as a function of temperature from 130K to 370K. We find that A, B and C are remarkably independent of the growth method. Theoretical calculations of the threshold carrier density as a function of temperature were also performed using a 10 band ?p Hamiltonian from which we could determine the temperature variation of A, B and C. At 300K, A=11x10-8 sec-1, B=8x10-11 cm3 sec-1 and C= 6x10-29 cm6 sec-1. These are compared with theoretical calculations of the coefficients and good agreement is obtained. Our results suggest that by eliminating defect-related currents and reducing optical losses, the threshold current density of these GaInNAs/GaAs-based edge-emitting devices would be more than halved at room temperature. The results from studies of temperature and pressure variation of ~1.3um VCSELs produced by similar MBE growth could also be explained using the same recombination coefficients. They showed a broad gain spectrum and were able to operate over a wide temperature range.

Adams, Alfred R.; Fehse, Robin; Tomic, Stanko; O'Reilly, Eoin P.; Andreev, Aleksey D.; Knowles, Gareth; Sale, Terry E.; Sweeney, Stephen J.; Steinle, Gunther; Ramakrishnan, A.; Riechert, Henning

2002-08-01

195

Physicochemical properties of the modeled structure of astacin metalloprotease moulting enzyme NAS-36 and mapping the druggable allosteric space of Heamonchus contortus, Brugia malayi and Ceanorhabditis elegans via molecular dynamics simulation.  

PubMed

Nematodes represent the second largest phylum in the animal kingdom. It is the most abundant species (500,000) in the planet. It causes chronic, debilitating infections worldwide such as ascariasis, trichuriasis, hookworm, enterobiasis, strongyloidiasis, filariasis and trichinosis, among others. Molecular modeling tools can play an important role in the identification and structural investigation of molecular targets that can act as a vital candidate against filariasis. In this study, sequence analysis of NAS-36 from H. contortus (Heamonchus contortus), B. malayi (Brugia malayi) and C. elegans (Ceanorhabditis elegans) has been performed, in order to identify the conserved residues. Tertiary structure was developed for an insight into the molecular structure of the enzyme. Molecular Dynamics Simulation (MDS) studies have been carried out to analyze the stability and the physical properties of the proposed enzyme models in the H. contortus, B. malayi and C. elegans. Moreover, the drug binding sites have been mapped for inhibiting the function of NAS-36 enzyme. The molecular identity of this protease could eventually demonstrate how ex-sheathment is regulated, as well as provide a potential target of anthelmintics for the prevention of nematode infections. PMID:24402824

Sharma, Om Prakash; Agrawal, Sonali; Kumar, M Suresh

2013-12-01

196

LAPMinistrio da Cincia e Tecnologia -Instituto Nacional de Pesquisas Espaciais -Laboratrio Associado de Plasma Macroscopic instabilities in lightning  

E-print Network

Associado de Plasma Macroscopic instabilities in lightning 1 2 G.O. Ludwig , M.M.F. Saba 1 2 Laboratório Characteristics of lightning discharges Typically, a lightning stroke lowers negative charge to earth from over a distance of 5km. The first return stroke in a lightning discharge is preceded by a stepped

197

PERCURSOS E TRAVESSIAS NO MORRO DA PROVIDNCIA: DESAFIOS DAS INTERAES SOCIAIS E ESPACIAIS NO JOGO FORMAL/INFORMAL  

E-print Network

NO JOGO FORMAL/INFORMAL COURSES AND CROSSINGS IN THE FAVELA MORRO DA PROVID�NCIA: CHALLENGES OF THE SOCIAL modalidades de apropriação do espaço. Palavras-chave: percursos; jogos de poder; interação social e espacial

Paris-Sud XI, Université de

198

Homogeneizao em Equaes Diferenciais Mtodo de Mltiplas Escalas  

E-print Network

Paulo - Brasil 2 Partially supported by FAPESP 2008/53094-4, CAPES DGU 127/07 and CNPq 305210/2008-4. marcone@usp.br Verão 2011 - IME - USP #12;Referências: 1 D. Cioranescu and P. Donato; An Introduction). 3 E. Sánchez-Palencia; Non-Homogeneous Media and Vibration Theory, Lecture Notes in Physics 127

Pereira, Marcone Corrêa

199

Validação cruzada de uma escala de clima organizacional  

Microsoft Academic Search

Cross validation of a scale of organizational climate. The stability of the factor structure of a scale of organizational climate of 66 items was investigated. A sample of 61,349 respondents was randomly divided in two parts, the first to identify the factor structure, the second to verify its replicability. The criterion used to identify the number of factors resulted in

Jacob A. Laros; Katia E. Puente-Palacios

2004-01-01

200

Response to Questions on Presentation to NAS  

SciTech Connect

Response to questions on the presentation 'Overview to Chamber and Power Plant Designs for IFE' made at the 1/29-31 meeting of the National Academies Committee on the Prospects for Inertial Confinement Fusion Energy Systems.

Meier, W R

2011-03-17

201

UAS Integration in the NAS Project  

E-print Network

of Unmanned Aircraft Systems · Mission ­ Utilize integrated system level tests in a relevant environment to reduce technical barriers related to the safety and operational challenges of Unmanned Aircraft Systems direction. ­ Numerous meetings have occurred with the FAA Unmanned Aircraft Program Office (UAPO

202

F/NAS/ Pressure Temperature Retrieval Techniques  

NASA Technical Reports Server (NTRS)

The purpose of this investigation is to study methods and ways for rapid inversion programs involving the correlated k-method, and to modify the existing programs so that the rapid analysis of data can be accomplished. The earth's atmosphere as well as those around the planets consist of gases which emit radiation in the infrared spectral region, providing wealth of information about chemical and physical processes in the atmosphere. The atmospheric molecular constituents absorb and radiate by vibrational and rotational transitions, and the observed spectra exhibit characteristic spectral features in the region of the electromagnetic spectrum. The observed absorption or thermal emission spectra may be obtained with space-borne high resolution infrared spectrometers the 50-1000 micrometers spectral region. A detailed analysis of the observed spectra leads to information about the atmospheric thermal structure, composition, and the physical and chemical processes. The analytic techniques involve the development of radiative transfer models for the calculation of the observed radiance and transmittances for realistic atmospheric conditions and observational geometries, and the development of inversion methods for retrieval of atmospheric parameters from the observations.

Poularikas, Alexander

1998-01-01

203

F/NAS/ Pressure Temperature Retrieval Techniques  

NASA Technical Reports Server (NTRS)

The purpose of this investigation is to study methods and ways for rapid inversion programs involving the correlated k-method, and to modify the existing programs so that the rapid analysis of data can be accomplished. This short paper presents the background regarding the research as well as accomplishments made during the contract period.

Poularikas, Alexander

1995-01-01

204

Task parallel implementation of NAS parallel benchmarks.  

E-print Network

??The multi-core era brings new challenges to the programming community. Parallelization requirements of applications in mainstream computing and applications in emergent fields of high performance… (more)

Nanjaiah, Shashi Kumar

2010-01-01

205

CONTRACT NAS5-22386 ,-.IP..1.,-_  

E-print Network

to confirm this theory two studies were conducted, !_ F" a theoretical one by the Bendix Corporation which be caused by the Incidence slowly mov- Ing highly charged particles. !? This theory was confirmed established, it Work Performed The program FREQ was modified to separate high and low PNA distributions

Rathbun, Julie A.

206

Multiband GaNAsP Quaternary Alloys  

SciTech Connect

We have synthesized GaN{sub x}As{sub 1-y}P{sub y} alloys (x {approx} 0.3-1% and y = 0-0.4) using nitrogen N ion implantation into GaAsP epilayers followed by pulsed laser melting and rapid thermal annealing techniques. As predicted by the band anticrossing model, the incorporation of N splits the conduction band (E{sub M}) of the GaAs{sub 1-y}P{sub y} substrate, and strong optical transitions from the valence band to the lower (E{sub -}) and upper (E{sub +}) conduction subbands are observed. The relative strengths of the E{sub -} and E{sub +} transition change as the localized N level E{sub N} emerges from the conduction band forming narrow intermediate band for y > 0.3. The results show that GaN{sub x}As{sub 1-x-y}P{sub y} alloys with y > 0.3 is a three band semiconductor alloy with potential applications for high-efficiency intermediate band solar cells.

Yu, K.M.; Walukiewicz, W.; Ager III, J.W.; Bour, D.; Farshchi,R.; Dubon, O.D.; Li, S.X.; Sharp, I.D.; Haller, E.E.

2005-12-08

207

Strategic Plans for the Future of Solar Physics: a community discussion of the NASA Sun-Earth Connection Program Roadmap and the NAS Decadal Survey of Astronomy and Astrophysics (Solar Astronomy section)  

NASA Astrophysics Data System (ADS)

The NASA Sun-Earth Connections Program is currently revising its Roadmap, the long-range plan for science goals, technology development, and missions between 2000 and 2040. From the interior dynamics of the Sun, to the interactions of plasma, fields, and radiation in the photosphere and solar atmosphere, to the heating and structure of the corona, to the acceleration, structure, and evolution of the solar wind, to the interactions of the heliosphere with the interstellar medium, to the processes of solar, stellar, and solar system evolution - progress in each of these domains will help us understand how the Sun impacts our home in space. The Roadmap Committee is seeking to refine and extend the SEC's vision and identify the milestone missions for the future. During this session, an outline of the current draft Roadmap will be presented, and further community involvement will be solicited to ensure the strongest possible concensus on the revised Roadmap. The National Academy of Sciences' Space Science Board has appointed a committee to perform a Decadal Survey of Astronomy and Astrophysics, which is surveying the field of space- and ground-based astronomy and astrophysics, recommending priorities for the most important new initiatives of the decade 2000-2010. The prioritization delivered by the earlier Decadal Surveys has played an important role in guiding the funding agencies in setting their priorities for astronomy and astrophysics. Therefore it will be of crucial importance for solar physics to contribute a strong case for its own set of future projects to be incorpoprated into the survey. The solar physics of the next decade will be characterized by its increasing societal relevance in the context of the National Space Weather Program and related issues, as well as its classical importance as a ``base" for many astrophysical questions. The presentation and subsequent discussion at the Chicago meeting is intended to solicit further community input, to achieve optimal representation for solar physics in the Decadal Survey. The Roadmap Committee and the Decadal Survey's solar panel encourage the whole solar physics community to contact them prior to the meeting. The list of the committee/panel members and their e-mail addresses, as well as related information, can be accessed via their websites at http://www.lmsal.com/sec/ and http://www.nas.edu/bpa/projects/astrosurvey/solar/ , respectively.

Schrijver, K.; Knoelker, M.

1999-05-01

208

Comparison of methods for the calculation of thermal contact resistance of the first Brazilian satellite. M.S. Thesis - Instituto de Pesquisas Espaciais, 6 Dec. 1985  

NASA Technical Reports Server (NTRS)

A comparative study of the methods developed for the calculation of thermal contact resistance between two surfaces submitted to a perpendicular heat flux is presented. Several factors affecting this resistance are analyzed and a brief historical review of the works in this field is made, spotting the methods of interest for space applications. These are compared to experimental data so as to establish the most proper method for the couplings of the first Brazilian satellite.

Mantelli, Marcia B. H.

1988-01-01

209

Escala de Clima Espacial de NOAA URL: www.sec.noaa.gov January 10, 2001  

E-print Network

redes de trasmisión pueden colapsar, y los transformadores pueden llegar a sufrir daños. Operaciones de, problemas con los enlaces y el seguimiento de satélites. Otros sistemas: La corriente inducida en las redes eléctrica en las redes de distribución de combustibles afecta las medidas preventivas, hay bloqueos

210

LA ESCALA ZONAL, REGIONAL Y LOCAL EN EL ANÁLISIS DEL RÉGIMEN PLUVIOMÉTRICO DEL ISTMO CENTROAMERICANO  

Microsoft Academic Search

The study is focused on geographic climatology; therefore the main geographical analysis instrument is the scale. To analyze the distribution of rain in Central America there has been defined three scales: the zonal, the regional and the local; each one of these scales presents concrete characteristics by the influence of the isthmic condition and the mountain relief; nevertheless the local

Gilbert Vargas Ulate

211

UMA ABORDAGEM ALGBRICA PARA WORKFLOWS CIENTFICOS COM DADOS EM LARGA ESCALA  

E-print Network

.Sc. ________________________________________________ Prof. Jano Moreira de Souza, Ph.D. ________________________________________________ Profa . Claudia algoritmos; � Claudia Bauzer de Medeiros, Jano Moreira de Souza e Marco Antônio Casanova, por terem aceitado Júnior, Fellipe Duarte, João Quadros, Jorge Abreu, Myrna Amorim, Rafael Castaneda, Renato Mauro, pelo

Paris-Sud XI, Université de

212

NAS Albuquerque 3/20/11 National Academy of Science  

E-print Network

depends on this spatial input of energy 3/30/2011 8 #12;Neutron yield 2.5 kJ, 1.2 ns flat top pulse, 2 10 TargetGain Laser Energy (MJ) NIC Central Hot Spot Igni on Fast Igni on FI Potentially Has ressure oresholein oronal asma Laser Electrons (hole-boring) Electrons (cone-guided) Protons DT fuel C

213

NAS/NAE Committee on the Prospects for IFE Systems  

E-print Network

-Driven Inertial Fusion Energy; Direct-Drive Targets Wrap Up R. L. McCrory Professor of Physics and Astronomy · Ignitionshouldbedemonstratedforany conceptbeforeprogressingtothefirstplant · LLEisdevelopingthephysicsbasisfor direct-drive ignition-pumpedIFEpowerplant system issues are the same for direct- and indirect-drive concepts ­ laser system design, including

214

Implementation of NAS Parallel Benchmarks in High Performance Fortran  

Microsoft Academic Search

We present an HPF implementation of BT, SP, LU, FT, CG and MG of the NPB2.3-serial benchmark set. The implementation is based on HPF perfor- mance model of the benchmark specific primitive operations with distributed arrays. We present pro- filing and performance data on SGI Origin 2000 and compare the results with NPB2.3. We discuss advantages and limitations of HPF

Michael Frumkin; Haoqiang Jin; Jerry Yan

2000-01-01

215

OBJECT-ORIENTED IMPLEMENTATION FOR NAS PARALLEL BENCHMARKS  

Microsoft Academic Search

ion deals with the external behavior of an objectwhile encapsulation helps manage the system complexity by hiding theinternal details of the object implementation. Thus, the abstraction andencapsulation complement each other in dealing with the complexity. Often,a set of abstractions in real life systems forms a hierarchy. Inheritanceorganizes the classes in a hierarchical structure, which gives a greater level ofabstraction to

Siva Linga Korlakunta

1995-01-01

216

Implementation of NAS parallel benchmarks in high performance fortran  

Microsoft Academic Search

Abstract We present an HPF implementation of BT, SP, LU, FT, CG and MG of the NPB2.3-serial benchmark set. The implementation,is based on HPF performance,model,of the benchmark,specific primitive operations with distributed arrays. We present profiling and performance,data on SGI Origin 2000 and compare,the results with NPB2.3. We discuss advantages,and limitations of HPF and pghpf compiler.

M. Frumkin; H. Jin; J. Yan

1998-01-01

217

Performance of the NAS Parallel Benchmarks on Grid Enabled Clusters  

Microsoft Academic Search

As Grids become more available and mature in real world settings, users are faced with considerations regard- ing the efficiency of applications and their capability of uti- lizing additional nodes distributed over a wide area net- work. When both tightly coupled clusters and loosely gath- ered Grids are available, a cost effective organization will schedule applications that can execute with

Philip J. Sokolowski; Daniel Grosu

2004-01-01

218

TRANSFORMING THE NAS: THE NEXT GENERATION AIR TRAFFIC CONTROL SYSTEM  

Microsoft Academic Search

The next-generation air-traffic control system will have to be able to handle, safely and efficiently, a traffic density that will be two or three times that accommodated by the present system. Capacity of the en route and transition (arrival\\/departure) airspace of the present system is principally limited by the controller workload associated with monitoring and controlling aircraft separation. Therefore, the

Heinz Erzberger

219

Transforming the NAS: The Next Generation Air Traffic Control System  

NASA Technical Reports Server (NTRS)

The next-generation air traffic control system must be designed to safely and efficiently accommodate the large growth of traffic expected in the near future. It should be sufficiently scalable to contend with the factor of 2 or more increase in demand expected by the year 2020. Analysis has shown that the current method of controlling air traffic cannot be scaled up to provide such levels of capacity. Therefore, to achieve a large increase in capacity while also giving pilots increased freedom to optimize their flight trajectories requires a fundamental change in the way air traffic is controlled. The key to achieving a factor of 2 or more increase in airspace capacity is to automate separation monitoring and control and to use an air-ground data link to send trajectories and clearances directly between ground-based and airborne systems. In addition to increasing capacity and offering greater flexibility in the selection of trajectories, this approach also has the potential to increase safety by reducing controller and pilot errors that occur in routine monitoring and voice communication tasks.

Erzberger, Heinz

2004-01-01

220

O Conceito de Resiliência Aplicado ao Trabalho nas Organizações  

Microsoft Academic Search

Resilience is a concept that has been used to explain psychosocial phenomena referred to individuals, groups or organizations that surpass or transcend adverse situations. In this study, the use of the concept of resilience as a theoretical referential in the field of Psychology of Work is discussed through: a) content analysis of two recent films - Frida and Life is

Lisete Barlach; Ana Cristina Limongi-França; Sigmar Malvezzi

2008-01-01

221

Comparison of leading parallel NAS file systems on commodity hardware  

SciTech Connect

High performance computing has experienced tremendous gains in system performance over the past 20 years. Unfortunately other system capabilities, such as file I/O, have not grown commensurately. In this activity, we present the results of our tests of two leading file systems (GPFS and Lustre) on the same physical hardware. This hardware is the standard commodity storage solution in use at LLNL and, while much smaller in size, is intended to enable us to learn about differences between the two systems in terms of performance, ease of use and resilience. This work represents the first hardware consistent study of the two leading file systems that the authors are aware of.

Hedges, R; Fitzgerald, K; Gary, M; Stearman, D M

2010-11-08

222

NAS-NS-3049(Rev.)' NUCLEAR SCIENCE SERIES  

E-print Network

, Chairman Robley D. Evans, Vice Chairman Yale University MassachusettsInstitute of Technology Lewis SlackPolytechnic Institute Richard M. Diamond Lawrence Radiation Laboratory Jerome Hudis Brookhavan National Laboratory Bruce Pacific Northwest Laboratories G. D. O'Keliey Oak Ridge National Laboratory Ellis P. Steinberg Argonne

223

Feasibility study for a secondary Na/S battery  

NASA Technical Reports Server (NTRS)

The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.

Abraham, K. M.; Schiff, R.; Brummer, S. B.

1979-01-01

224

Protótipo do primeiro interferômetro brasileiro - BDA  

NASA Astrophysics Data System (ADS)

A interferometria é uma poderosa ferramenta usada para investigar estruturas espaciais de fontes astrofísicas fornecendo uma riqueza de detalhes inatingível pelas técnicas convencionais de imageamento. Em particular, a interferometria com ondas de rádio abre o horizonte de conhecimento do Universo nesta ampla banda do espectro eletromagnético, que vai de cerca de 20 kHz até centenas de GHz já próximo ao infravermelho, e que está acessível a partir de instrumentos instalados em solo. Neste trabalho, apresentamos o interferômetro designado por Arranjo Decimétrico Brasileiro (BDA). Trata-se do primeiro interferômetro a ser desenvolvido no Brasil e América Latina que já está em operação na fase de protótipo. Apresentamos o desenvolvimento realizado até o momento, o sítio de instalação do instrumento, o protótipo e os principais resultados dos testes de sua operação, as perspectivas futuras e a ciência a ser desenvolvida com o instrumento nas fases II e III. Neste trabalho é dada ênfase ao desenvolvimento, testes de operação e principais resultados do protótipo. É discutida brevemente a ciência que pode ser feita com o instrumento. Tanto os detalhes técnicos quanto os principais parâmetros estimados para o instrumento nas próximas fases de desenvolvimento e o desempenho do protótipo serão publicados em breve.

Cecatto, J. R.; Fernandes, F. C. R.; Neri, J. A. C. F.; Bethi, N.; Felipini, N. S.; Madsen, F. R. H.; Andrade, M. C.; Soares, A. C.; Alonso, E. M. B., Sawant, H. S.

2004-04-01

225

Alterações cognitivas e demência na doença de Parkinson.  

E-print Network

??Na Doença de Parkinson (DP), mesmo nos seus estádios iniciais, vários domínios cognitivos estão alterados, incluindo funções executivas, funções visuo-espaciais, memória e linguagem. O risco… (more)

Santos, Filipe Sobral Blanco Heleno

2009-01-01

226

Avaliação nutricional do milho com maior teor de óleo, nas formas de grãos secos e silagens, para suínos nas fases de crescimento e terminação  

Microsoft Academic Search

Two experiments were carried out to determine nutritive value and verify performance of growing and finishing swine feed high moisture corn silage (HMCS) and reconstituted silage (RS) of higher oil corn. The digestibility assay was carried twelve cross breed barrow, were allotted in metabolism cages, in a completely randomized design. The values of digestible dry matter (DDM), digestible protein (DP),

Marcos Augusto Alves da Silva; Antonio Claudio Furlan; Ivan Moreira; Diovani Paiano; Clóves Cabreira Jobim; Livia Carla Grigoletto Barcellos

2006-01-01

227

UAS Integration into the NAS: HSI Full Mission Simulation Preliminary Results  

NASA Technical Reports Server (NTRS)

The goal of the Full Mission Sim was to examine the effects of different command and control interfaces on UAS pilots' ability to respond to ATC commands and traffic advisories. Results suggest that higher levels of automation (i.e., waypoint-to-waypoint control interfaces) lead to longer initial response times and longer edit times. The findings demonstrate the importance of providing pilots with interfaces that facilitate their ability to get back "in the loop."

Shively, Jay; Fern, Lisa; Rorie, Conrad

2014-01-01

228

UAS Integration in the NAS Project Overview: RTCA SC-228 Plenary DAA Working Group 5  

NASA Technical Reports Server (NTRS)

The presentation is intended to allow the public to know and understand NASA's plans for integrated test to allow them the opportunity to provide feedback and suggestions. The integrated testing will support verification and validation of the RTCA SC-228 UAS minimum operation performance standard requirements.

Randall, Debra K.

2014-01-01

229

DO "PRETO" DO CESTO AO MOLEQUE DO VINTM: A ESCRAVIDO NAS COMDIAS DE  

E-print Network

aproximadamente de dois terços de negros, escravos ou livres5 e concentrava-se no Rio de Janeiro, a "Corte" onde (24%).9 Além disso, em meados do século XIX era ela que comercializava no mercado exterior a maior

Paris-Sud XI, Université de

230

Variações nas frentes de gelo da Enseada Martel, Ilha Rei George, Antártica, entre 1956 e 2000  

Microsoft Academic Search

Ice masses in subpolar regions may respond rapidly to changes in atmospheric temperature. This study verified variations in ice front positions at Martel Inlet, King George Island, Antarctica, from 1956 to 2000, using maps produced from aerial photogrammetric surveys and satellite imagery. General retreat of ice fronts were observed through four decades, which means that 3.55 km2 of the ice

JORGE ARIGONY NETO; ULISSES FRANZ BREMER; JEFFERSON CARDIA SIMÕES

231

48 CFR 852.236-82 - Payments under fixed-price construction contracts (without NAS).  

Code of Federal Regulations, 2010 CFR

...equipment 5 Prefab temperature rooms (cold, constant temperature) 5 Entire...requirements and/or approved samples and shop drawings. (2) Only those materials and...withhold payment until samples, shop drawings, engineer's certificates,...

2010-10-01

232

48 CFR 852.236-83 - Payments under fixed-price construction contracts (including NAS).  

Code of Federal Regulations, 2010 CFR

...equipment 5 Prefab temperature rooms (cold, constant temperature) 5 Entire...requirements and/or approved samples and shop drawings. (2) Only those materials and...withhold payment until samples, shop drawings, engineer's certificates,...

2010-10-01

233

NATIONAL ACADEMY OF SCIENCES (NAS) REVIEW OF THE HEALTH IMPLICATIONS OF PERCHLORATE INGESTION (2005)  

EPA Science Inventory

In the interest of resolving scientific questions, the EPA, the Department of Defense, the Department of Energy, and the National Aeronautics and Space Administration - members of a broader Interagency Working Group on Perchlorate led by the Office of Science and Technology Polic...

234

Multi-agent Simulation of NAS Infrastructure Utilization in the Presence of Airline Policies  

E-print Network

the safety rules (separation distances). Usually, aircraft wait on the ground until the controllers allow ]. This paper uses a multi-agent-based simulation to model aircraft operations and infrastructure utilization in the presence of airline policies and aircraft route selection strategies. The main hypothesis of the paper

235

A Family of Well-Clear Boundary Models for the Integration of UAS in the NAS  

E-print Network

, VA, 23881, US The FAA-sponsored Sense and Avoid Workshop for Unmanned Aircraft Systems (UAS) defines of Approach UAS Unmanned Aircraft Systems Corresponding Author. Email: cesar.a.munoz@nasa.gov. AIAA Member. 1 of integrating Unmanned Aircraft Systems (UAS) into the airspace system is the lack of an on-board pilot

Muñoz, César A.

236

Validação das equações do NRC (2001) para predição do valor energético de alimentos nas condições brasileiras  

Microsoft Academic Search

This research was developed to estimate the energy values (TDN) of feeds, concentrate and roughage, through equations proposed by NRC (2001) and validate from the comparison among TDN values estimated by these equations and those observed in the total collection feces. Five concentrate feeds (wheat bran, soybean meal, corn ground, whole soybean and whole cotton seed) an five roughage feeds

Marcos Antonio Lana Costa; Sebastião de Campos Valadares Filho; Rilene Ferreira Diniz Valadares; Mário Fonseca Paulino; Paulo Roberto Cecon; Pedro Veiga Rodrigues Paulino; Mário Luiz Chizzotti; Mônica Lopes Paixão

2005-01-01

237

An Integrated Approach to Evaluating Risk Mitigation Measures for UAV Operational Concepts in the NAS  

E-print Network

An integrated approach is outlined in this paper to evaluate risks posed by operating Unmanned Aerial Vehicles in the National Airspace System. The approach supports the systematic evaluation of potential risk mitigation ...

Weibel, Roland E

2005-09-26

238

United States and available alternative energy sources. [Summary of NAS\\/CONAES study  

Microsoft Academic Search

This article is a summary of the National Academy of Sciences' Committee on Nuclear and Alternative Energy systems (CONAES) study. The CONAES study emphasized the challenges facing the United States in the medium term, when the country will have to make a transition from major dependence on fossil hydrocarbons to utilization of other available or renewable energy sources. Energy conservation

Maalouf

1980-01-01

239

CYCLIC HOMOLOGY, cdhCOHOMOLOGY AND NEGATIVE NAS, C. HAESEMEYER, M. SCHLICHTING, AND C. WEIBEL  

E-print Network

00958. Haesemeyer's research was partially supported by the Bell Companies Fellowship and RTN Network HPRN­CT­2002­00287. Schlichting's research was partially supported by RTN Network HPRN­CT­2002

240

BOREAS TE-9 In Situ Diurnal Gas Exchange of NAS Boreal Forest Stands  

NASA Technical Reports Server (NTRS)

The BOREAS TE-9 team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. The purpose of the BOREAS TE-09 study was threefold: 1) to provide in situ gas exchange data that will be used to validate models of photosynthetic responses to light, temperature, and carbon dioxide (CO2); 2) to compare the photosynthetic responses of different tree crown levels (upper and lower); and 3) to characterize the diurnal water potential curves for these sites to get an indication of the extent to which soil moisture supply to leaves might be limiting photosynthesis. The gas exchange data of the BOREAS NSA were collected to characterize diurnal gas exchange and water potential of two canopy levels of five boreal canopy cover types: young jack pine, old jack pine, old aspen, lowland old black spruce, and upland black spruce. These data were collected between 27-May-1994 and 17-Sep-1994. The data are provided in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Margolis, Hank; Coyea, Marie; Dang, Qinglai

2000-01-01

241

Large UAS Operations in the NAS - The NASA 2007 Western States Fire Missions (WSFM)  

NASA Technical Reports Server (NTRS)

Objectives: Demonstrate capabilities of UAS to overfly and collect sensor data on wildfires throughout Western US. Demonstrate long-endurance mission capabilities (20+ hours). Image multiple fires (greater than 4 fires per mission), to showcase extendable mission configuration and ability to either linger over key fires or station over disparate regional fires. Deliver real-time imagery to (within 10-minutes of acquisition).

Buoni, Gregory P.; Howell, Kathleen M.

2008-01-01

242

HPF and MPI Implementation of the NAS Parallel Benchmarks Supported by Integrated Program Engineering Tools  

Microsoft Academic Search

High Performance Fortran (HPF) compilers and communication libraries with the standardized Mes- sage Passing Interface (MPI) are becoming widely avail- able, easing the development of portable parallel appli- cations on distributed-memory parallel processor systems . The recently developed Annai tool environment supports programming, debugging and tuning of both HPF- and MPI-based applications. Considering code development and subsequent maintenance time to

Christian Cl; Karsten M. Decker; Vaibhav R. Deshpande; Akiyoshi Endo; Josef Fritscher; Paulo A. R. Lorenzo; Norio Masuda; William Sawyer; Brian J. N. Wylie; Frank Zimmermann

243

Performance characterization of the NAS Parallel Benchmarks in OpenCL  

Microsoft Academic Search

Heterogeneous parallel computing platforms, which are composed of different processors (e.g., CPUs, GPUs, FPGAs, and DSPs), are widening their user base in all computing domains. With this trend, parallel programming models need to achieve portability across different processors as well as high performance with reasonable programming effort. OpenCL (Open Computing Language) is an open standard and emerging parallel programming model

Sangmin Seo; Gangwon Jo; Jaejin Lee

2011-01-01

244

Design of Unstructured Adaptive (UA) NAS Parallel Benchmark Featuring Irregular, Dynamic Memory Accesses  

NASA Technical Reports Server (NTRS)

We describe the design of a new method for the measurement of the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. The method involves the solution of a stylized heat transfer problem on an unstructured, adaptive grid. A Spectral Element Method (SEM) with an adaptive, nonconforming mesh is selected to discretize the transport equation. The relatively high order of the SEM lowers the fraction of wall clock time spent on inter-processor communication, which eases the load balancing task and allows us to concentrate on the memory accesses. The benchmark is designed to be three-dimensional. Parallelization and load balance issues of a reference implementation will be described in detail in future reports.

Feng, Hui-Yu; VanderWijngaart, Rob; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

2001-01-01

245

Performance Evaluation of the MPI\\/MBCF with the NAS Parallel Benchmarks  

Microsoft Academic Search

. MPI\\/MBCF is a high-performance MPI library targeting acluster of workstations connected by a commodity network. It is implementedwith the Memory-Based Communication Facilities (MBCF),which provides software mechanisms for users to access remote task'smemory space with off-the-shelf network hardware. MPI\\/MBCF usesMemory-Based FIFO for message buffering and Remote Write for communicationwithout buffering from among the functions of MBCF. Inthis paper, we evaluate

Kenji Morimoto; Takashi Matsumoto; Kei Hiraki

1999-01-01

246

Automated Generation of Message-Passing Programs: An Evaluation of CAPTools using NAS Benchmarks  

NASA Technical Reports Server (NTRS)

Scientists at NASA Ames Research Center have been developing computational aeroscience applications on highly parallel architectures over the past ten years. During the same time period, a steady transition of hardware and system software also occurred, forcing us to expand great efforts into migrating and receding our applications. As applications and machine architectures continue to become increasingly complex, the cost and time required for this process will become prohibitive. Various attempts to exploit software tools to assist and automate the parallelization process have not produced favorable results. In this paper, we evaluate an interactive parallelization tool, CAPTools, for parallelizing serial versions of the NAB Parallel Benchmarks. Finally, we compare the performance of the resulting CAPTools generated code to the hand-coded benchmarks on the Origin 2000 and IBM SP2. Based on these results, a discussion on the feasibility of automated parallelization of aerospace applications is presented along with suggestions for future work.

Hribar, Michelle R.; Jin, Hao-Qiang; Yan, Jerry C.; Bailey, David (Technical Monitor)

1998-01-01

247

Tools-supported HPF and MPI parallelization of the NAS parallel benchmarks  

Microsoft Academic Search

High Performance Fortran (HPF) compilers and communication libraries with the standardized Message Passing Interface (MPI) are becoming widely available, easing the development of portable parallel applications. The Annai tool environment supports programming, debugging and tuning of both HPF- and MPI-based applications. Considering code development time to be as important as final performance, we address how sequential versions of the familiar

C. Clemencon; Karsten M. Decker; Vaibhav R. Deshpande; Akiyoshi Endo; Josef Fritscher; Paulo A. R. Lorenzo; Norio Masuda; Andreas Muller; R. Ruhl; W. Sawyer; B. J. N. Wylie; F. Zimmermann

1996-01-01

248

NPB-MPJ: NAS Parallel Benchmarks Implementation for Message-Passing in Java  

Microsoft Academic Search

Java is a valuable and emerging alternative for the development of parallel applications, thanks to the availability of several Java message-passing libraries and its full multithreading support. The combination of both shared and distributed memory programming is an interesting option for parallel programming multi-core systems. However, the concerns about Java performance are hindering its adoption in this field, although it

Damián A. Mallón; Guillermo L. Taboada; Juan Touriño; Ramon Doallo

2009-01-01

249

Coloração verde nas folhas da cultura do alho vernalizado em resposta à adubação nitrogenada  

Microsoft Academic Search

GREEN HUE IN VERNALIZED GARLIC LEAVES IN RESPONSE TO NITROGEN FERTILIZATION A field experiment was carried out in order to determine the feasibility of monitoring nitrogen fertilization of vernalized garlic production by means of the correlation between the indirect measurement of the intensity of the green hue of the leaves (SPAD chlorophyll meter) and the plant nutritional condition and bulb

Clarice Backes; Claudinei Paulo de Lima; Leandro José Grava de Godoy; Roberto Lyra Villas Bôas; Isao Imaizumi

2008-01-01

250

Evaluation of the Terminal Precision Scheduling and Spacing System for Near-Term NAS Application  

NASA Technical Reports Server (NTRS)

NASA has developed a capability for terminal area precision scheduling and spacing (TAPSS) to provide higher capacity and more efficiently manage arrivals during peak demand periods. This advanced technology is NASA's vision for the NextGen terminal metering capability. A set of human-in-the-loop experiments was conducted to evaluate the performance of the TAPSS system for near-term implementation. The experiments evaluated the TAPSS system under the current terminal routing infrastructure to validate operational feasibility. A second goal of the study was to measure the benefit of the Center and TRACON advisory tools to help prioritize the requirements for controller radar display enhancements. Simulation results indicate that using the TAPSS system provides benefits under current operations, supporting a 10% increase in airport throughput. Enhancements to Center decision support tools had limited impact on improving the efficiency of terminal operations, but did provide more fuel-efficient advisories to achieve scheduling conformance within 20 seconds. The TRACON controller decision support tools were found to provide the most benefit, by improving the precision in schedule conformance to within 20 seconds, reducing the number of arrivals having lateral path deviations by 50% and lowering subjective controller workload. Overall, the TAPSS system was found to successfully develop an achievable terminal arrival metering plan that was sustainable under heavy traffic demand levels and reduce the complexity of terminal operations when coupled with the use of the terminal controller advisory tools.

Thipphavong, Jane; Martin, Lynne Hazel; Swenson, Harry N.; Lin, Paul; Nguyen, Jimmy

2012-01-01

251

Correlation of DLTS and Performance of GaInNAs Cells  

SciTech Connect

A four-junction GaInP/GaAs/GaInAsN/Ge solar cell should be able to reach 40% efficiency if each of the junctions can be made with a quality similar to that demonstrated for GaAs. However, the GaInAsN subcell has shown poor performance. Deep-level transient spectroscopy (DLTS) can elucidate recombination centers in a material and could help identify the problem with the GaInAsN. So far, DLTS studies of GaInAsN have shown many peaks. In this paper we compare the performance of the GaInAsN solar cells with the DLTS spectra to identify which DLTS peak is correlated with the device performance.

Kurtz, S.; Johnston, S.; Friedman, D.; Ptak, A.; Geisz, J.; McMahon, W.; Olson, J.; Kibbler, A.; Crandall, R.; Ahrenkiel, R.; Kramer, C.; Young, M.

2005-01-01

252

Support of Activities of the NAS in Relation to the Radiation Effects Research Foundation  

SciTech Connect

The National Academies (NA) provides support for the activities related to the long-term follow up of the health of the survivors of the atomic bombings of Hiroshima and Nagasaki being conducted by the Radiation Effects Research Foundation (RERF) laboratories in Hiroshima and Nagasaki, Japan. The NA serves as scientific and administrative liaison between the U.S. Department of Energy (DOE) and RERF, and performs tasks in the areas of scientific oversight, information/public interface, fiscal oversight, and personnel management. The project includes recruitment and support of approximately 10 NA employees who work at RERF in Japan. Specific activities are performed consistent with the cooperative agreement’s Statement of Work between DOE and NA and consistent with an Annual Work Plan developed by DOE and NA.

Douple, Evan B.

2006-05-31

253

Preliminary C3 Loading Analysis for Future High-Altitude Unmanned Aircraft in the NAS  

NASA Technical Reports Server (NTRS)

This document provides a preliminary assessment and summary of the command, control, and communications (C(sup 3)) loading requirements of a generic future high-altitude, long-endurance unmanned aircraft (UA) operating at in the National Airspace System. Two principal types of C(sup 3) traffic are considered in our analysis: communications links providing air traffic services (ATS) to the UA and its human pilot, and the command and control data links enabling the pilot to operate the UA remotely. we have quantified the loading requirements of both types of traffic for two different assumed levels of UA autonomy. Our results indicate that the potential use of UA-borne relays for the ATS links, and the degree of autonomy exercised by the UA during the departure and arrival phases of its flight, will be among the key drivers of C(sup 3) loading and bandwidth requirements.

Ho, Yan-Shek; Gheorghisor, Izabela; Box, Frank

2006-01-01

254

INFLUÊNCIA DA IDADE NAS CARACTERÍSTICAS FÍSICO -QUÍMICAS E ANATÔMICAS DA MADEIRA DE Eucalyptus saligna  

Microsoft Academic Search

Althroug the effects of age on the physical, chemical and anatomical characteristics of wood are well known, the extent to which these properties vary for the genus Eucalyptus is poorly studied. The present contribution had as main goal to assess the influence of age on the physical, chemical and anatomical characteristics of the wood of Eucalyptus saligna. The analyses were

Paulo Fernando Trugilho; José Tarcísio Lima; Lourival Marin Mendes

255

Gordon and Mike's ICT Podcast: NSF, NAS, etc and the SMET Pipeline  

NSDL National Science Digital Library

Gordon and Mike's ICT Podcast offers perspectives on the information and communication technologies (ICT) industries from Gordon Snyder and Mike Qaissaunee. In this podcast, Mike and Gordon discuss "Science, Math, Engineering and Technology (SMET) pipeline and work being done by the National Academy of Science and the National Science Foundation." Running time for the show is 16:57.This podcast is available for direct download in mp3 format from the Libsyn site, or click here to subscribe to the whole series in iTunes.

Qaissaunee, Michael

256

The Washington Alphabet Circa 1895-1905: NAS, USGS, SI, WAS, CC, GWMA, WMI, CIW  

NASA Astrophysics Data System (ADS)

Pursuit of science as part of the Federal responsibility to the American public was vigorously defended by John Wesley Powell in the 1880s, but received serious financial setback during the next decade. The following decade saw the gradual laying of foundations for the present-day non-academic component of "big science" through the development of a series of Federal and private organizations, some which were ephemeral. A key person in this alphabet soup has the initials CDW (Charles Doolittle Walcott). His influence will be discussed and if time permits, BM, NACA and NRC will be used to demonstrate methodology.

Yochelson, E. L.

2002-05-01

257

The Washington Alphabet Circa 1895-1905: NAS, USGS, SI, WAS, CC, GWMA, WMI, CIW  

Microsoft Academic Search

Pursuit of science as part of the Federal responsibility to the American public was vigorously defended by John Wesley Powell in the 1880s, but received serious financial setback during the next decade. The following decade saw the gradual laying of foundations for the present-day non-academic component of \\

E. L. Yochelson

2002-01-01

258

Determination of biaxial creep strength of T-111 tantalum alloy. Final report. NAS-CR--72846  

Microsoft Academic Search

One seamless and one welded and reworked biaxial creep test capsules of T-111 alloy tubing were tested at 2200°F for 5000 hours each in a high-vacuum environment. The sealed capsules were half filled with liquid potassium. The stress in the thin wall gauge sections was generated by the potassium vapor pressure generated within the refluxing capsule. Diametral measurements were made

G. P. Brandenburg; L. B. Jr. Engel

1971-01-01

259

Minority carrier transport properties of GaInNAs heterojunction bipolar transistors with 2% nitrogen  

E-print Network

% nitrogen Rebecca J. Welty,a) Huoping Xin, Charles W. Tu, and Peter M. Asbeck University of California) of 0.98 eV; this is achieved with a nitrogen composition of 2%. These devices have a turn-on voltage HFE is 8. The current gain of nitrogen containing HBTs is degraded due to the complex change

Asbeck, Peter M.

260

USO DA TOMOGRAFIA COMPUTADORIZADA NAS FRATURAS FACIAIS USE OF TOMOGRAPHY COMPUTADORIZED IN THE FACIAL FRACTURES  

Microsoft Academic Search

A face é uma região proeminente do corpo humano sujeita a injúrias de intensidade leve à grave, possuindo, em alguns casos, lesões associadas às outras partes do corpo. Assim, as fraturas que acometem a face possuem certas peculiaridades em relação ao seu diagnóstico e planejamento cirúrgico. A Tomografia Computadorizada apresenta imagens mais acuradas sem sobreposições, com maior detalhes das estruturas

Ana Cláudia; Amorim GOMES; Belmiro Cavalcanti; Egito VASCONCELOS

261

Analysis of Well-Clear Boundary Models for the Integration of UAS in the NAS  

NASA Technical Reports Server (NTRS)

The FAA-sponsored Sense and Avoid Workshop for Unmanned Aircraft Systems (UAS) defnes the concept of sense and avoid for remote pilots as "the capability of a UAS to remain well clear from and avoid collisions with other airborne traffic." Hence, a rigorous definition of well clear is fundamental to any separation assurance concept for the integration of UAS into civil airspace. This paper presents a family of well-clear boundary models based on the TCAS II Resolution Advisory logic. Analytical techniques are used to study the properties and relationships satisfied by the models. Some of these properties are numerically quantifed using statistical methods.

Upchurch, Jason M.; Munoz, Cesar A.; Narkawicz, Anthony J.; Chamberlain, James P.; Consiglio, Maria C.

2014-01-01

262

QUESTÕES EPISTEMOLÓGICAS NAS ICONICIDADADES DE REPRESENTAÇÕES VISUAIS EM LIVROS DIDÁTICOS DE FÍSICA  

Microsoft Academic Search

Abstract This article analyses a certain kind of philosophical message about the nature of science, tacitally conveyed by some visual represention presented by textbooks of physics. However, our purpose is not ,strictly to analyse ,all the existing visual representation in textbooks ,in all their characteristics, but only to point out a certain kind of usage of those representation which conveys

Alexandre Medeiros; Cleide Medeiros

263

Complejidad descriptiva y computacional en m\\'aquinas de Turing peque\\~nas  

E-print Network

En este trabajo ofrecemos algunos de los resultados obtenidos al estudiar las funciones calculadas por m\\'aquinas de Turing con un alfabeto de dos s\\'imbolos y un n\\'umero de estados entre 1 y 3. Presentamos detenidamente el modelo de m\\'aquina de Turing empleado, donde la cinta es ilimitada en un solo sentido, y no existe estado de parada. Mostramos gr\\'aficamente c\\'omo es posible representar la funci\\'on calculada por una m\\'aquina, as\\'i como las computaciones realizadas para ello. Vemos que al aumentar el n\\'umero de estados, si bien es posible que algunas funciones se calculen con mayor rapidez, por lo general aumenta considerablemente el tiempo medio de computaci\\'on.

Joosten, Joost J; Zenil, Hector

2010-01-01

264

La Apaicultura de Pequena Escala (Small Scale Beekeeping). Appropriate Technologies for Development. Peace Corps Information Collection & Exchange Manual Series No. M-25.  

ERIC Educational Resources Information Center

This Spanish-language manual is designed to assist Peace Corps volunteers in Spanish-speaking countries in the implementation of small-scale beekeeping programs as a tool for development. Addressed in the individual chapters are bees and humans; project planning; the types and habits of bees; the essence of beekeeping; bee space and beehives;…

Gentry, Curtis

265

Características psicométricas de la Escala Center for Epidemiological Studies-depression (CES-D), versiones de 20 y 10 reactivos, en mujeres de una zona rural mexicana  

Microsoft Academic Search

SUMMARY Depressive symptoms constitute a common mental health problem, with a relevant social and personal impact. These symptoms are present not only among the urban population in more economically developed countries, but also in rural areas in poor and middle development countries. In order to obtain reliable information on the frequency of depressive symptoms, their risk factors or the impact

Ietza Bojorquez Chapela; Nelly Salgado de Snyder

266

Frecuencia de uso de escalas de dolor, incapacidad fisica y calidad de vida en el estudio de lumbalgia con intervenciones fisioterápicas  

Microsoft Academic Search

ObjectiveTo determine use frequency of the different types of validated scales on pain, physical incapacity, and quality of life in the primary documents in general and specifically in the Randomized Control Trials (RCT) in physiotherapy interventions on low back pain, as a documental indicator of adequacy in order to make recommendations for the physiotherapy interventions in non-specific mechanical low back

A. I. Cuesta Vargas; A. Rodríguez Moya

2008-01-01

267

Excitation energy-dependent nature of Raman scattering spectrum in GaInNAs/GaAs quantum well structures  

PubMed Central

The excitation energy-dependent nature of Raman scattering spectrum, vibration, electronic or both, has been studied using different excitation sources on as-grown and annealed n- and p-type modulation-doped Ga1???xInxNyAs1???y/GaAs quantum well structures. The samples were grown by molecular beam technique with different N concentrations (y = 0%, 0.9%, 1.2%, 1.7%) at the same In concentration of 32%. Micro-Raman measurements have been carried out using 532 and 758 nm lines of diode lasers, and the 1064 nm line of the Nd-YAG laser has been used for Fourier transform-Raman scattering measurements. Raman scattering measurements with different excitation sources have revealed that the excitation energy is the decisive mechanism on the nature of the Raman scattering spectrum. When the excitation energy is close to the electronic band gap energy of any constituent semiconductor materials in the sample, electronic transition dominates the spectrum, leading to a very broad peak. In the condition that the excitation energy is much higher than the band gap energy, only vibrational modes contribute to the Raman scattering spectrum of the samples. Line shapes of the Raman scattering spectrum with the 785 and 1064 nm lines of lasers have been observed to be very broad peaks, whose absolute peak energy values are in good agreement with the ones obtained from photoluminescence measurements. On the other hand, Raman scattering spectrum with the 532 nm line has exhibited only vibrational modes. As a complementary tool of Raman scattering measurements with the excitation source of 532 nm, which shows weak vibrational transitions, attenuated total reflectance infrared spectroscopy has been also carried out. The results exhibited that the nature of the Raman scattering spectrum is strongly excitation energy-dependent, and with suitable excitation energy, electronic and/or vibrational transitions can be investigated. PMID:23190628

2012-01-01

268

Effects of rapid thermal annealing conditions on GaInNAs band gap blueshift and photoluminescence intensity  

E-print Network

Electronics, Wolfgang-Pauli-Strasse 16, CH-8093 Zürich, Switzerland S. Schön ETH Zurich, FIRST Center for Micro- and Nanoscience, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland Received 7 December 2005

Keller, Ursula

269

76 FR 57690 - TRICARE; Elimination of the Non-Availability Statement (NAS) Requirement for Non-Emergency...  

Federal Register 2010, 2011, 2012, 2013, 2014

...for Non-Emergency Inpatient Mental Health Care AGENCY: Office of the Secretary...for non-emergency inpatient mental health care in order for a TRICARE Standard...for non-emergency inpatient mental health care. Currently, the...

2011-09-16

270

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 210217. Periodic Soliton Solutions to  

E-print Network

Soliton Solutions to the Davey­Stewartson Equation Masayoshi TAJIRI and Takahito ARAI Department-mail: tajiri@nm.ms.osakafu-u.ac.jp E-mail: arai@nm.ms.osakafu-u.ac.jp The periodic soliton resonances the interaction between a y-periodic soliton and a line soliton are analyzed to show the existence of the soliton

Popovych, Roman

271

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 486492 Relation between Periodic Soliton Resonance  

E-print Network

between Periodic Soliton Resonance and Instability Masayoshi TAJIRI Graduate School of Engineering, Osaka soliton resonances in interactions between two periodic solitons and between periodic soliton and another kind of soliton. A close relation exists between the periodic soliton resonance and soliton instability

Popovych, Roman

272

Practical Simulation of Large-Scale Parallel Programs and Its Performance Analysis of the NAS Parallel Benchmarks  

Microsoft Academic Search

. A simulation technique for very large-scale data parallel programsis proposed. In our simulation method, a data parallel program isdivided into computation and communication sections. When the controlflow of the parallel program does not depend on the contents of networkmessages, the computation time on each processor is calculated independently.An instrumentation tool called EXCIT is used to calculate theexecution time on

Kazuto Kubota; Ken’ichi Itakura; Mitsuhisa Sato; Taisuke Boku

1998-01-01

273

A Comparison of Automatic Parallelization Tools/Compilers on the SGI Origin 2000 Using the NAS Benchmarks  

NASA Technical Reports Server (NTRS)

Porting applications to new high performance parallel and distributed computing platforms is a challenging task. Since writing parallel code by hand is extremely time consuming and costly, porting codes would ideally be automated by using some parallelization tools and compilers. In this paper, we compare the performance of the hand written NAB Parallel Benchmarks against three parallel versions generated with the help of tools and compilers: 1) CAPTools: an interactive computer aided parallelization too] that generates message passing code, 2) the Portland Group's HPF compiler and 3) using compiler directives with the native FORTAN77 compiler on the SGI Origin2000.

Saini, Subhash; Frumkin, Michael; Hribar, Michelle; Jin, Hao-Qiang; Waheed, Abdul; Yan, Jerry

1998-01-01

274

Performance Evaluation of the Concurrent Execution of NAS Parallel Benchmarks with BYTE Sequential Benchmarks on a Cluster  

Microsoft Academic Search

Computers of a non-dedicated cluster are often idle (users attend meetings, have lunch or coffee breaks) or lightly loaded (users carry out simple computations). These underutilized computers can be employed to execute parallel applications not only during weekends and at nights but also during office hours. Thus, they have to be shared by parallel and sequential applications which could lead

Andrzej M. Goscinski; Adam K. L. Wong

2005-01-01

275

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 569573 Symmetries and Supersymmetries  

E-print Network

^aj, #12;570 B. Militello, A. Nikitin and A. Messina where A is the relevant atomic Bohr frequency, ^3 and Supersymmetries in Trapped Ion Hamiltonian Models Benedetto MILITELLO , Anatoly NIKITIN and Antonino MESSINA-boson-like Hamiltonian model is studied exploiting its symmetries and supersymmetries. Applications are discussed. 1

Nikitin, Anatoly

276

A Biometric Latent Curve Analysis of Memory Decline in Older Men of the NAS-NRC Twin Registry  

PubMed Central

Previous research has shown cognitive abilities to have different biometric patterns of age-changes. Here we examined the variation in episodic memory (Words Recalled) for over 6,000 twin pairs who were initially aged 59-75, and were subsequently re-assessed up to three more times over 12 years. In cross-sectional analyses, variation in Education was explained by strong additive genetic influences (~43%) together with shared family influences (~35%) that were independent of age. The longitudinal phenotypic analysis of the Word Recall task showed systematic linear declines over age, but with positive influences of Education and Retesting. The longitudinal biometric estimation yielded: (a) A separation of non-shared environmental influences and transient measurement error (~50%): (b) Strong additive genetic components of this latent curve (~70% at age 60) with increases over age that reach about 90% by age 90. (c) The minor influences of shared family environment (~17% at age 60) were effectively eliminated by age 75. (d) Non-shared environmental effects play an important role over most of the life-span (peak of 42% at age 70) but their relative role diminishes after age 75. PMID:19404731

McArdle, John J.; Plassman, Brenda L.

2010-01-01

277

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 211213 Differential Invariants of Transformation Groups  

E-print Network

)x + 2yxy y y+(y )2 +1 P 3/2 2y P Dx 3 yx - xy, (1 + x2 - y2 )x + 2xyy, 2xyx + (1 + y2 - x2 )y y (1+x + yy, yx - xy, (x2 - y2 )x - 2xyy, 2xyx - (y2 - x2 )y U Q3 P Q Dx 8 x, y, xx, yy, yx, xy, x2 x + xyy

Popovych, Roman

278

Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 540547 Quantum Algebras, Particle Phenomenology,  

E-print Network

Algebras, Particle Phenomenology, and (Quasi)Supersymmetry A.M. GAVRILIK Bogolyubov Institute, within the application of quantum algebras Uq(sun) [1, 2] to phenomenological description (see [3, 4, 7 for the Gi, ¯Gi) have been utilized. By means of #12;Quantum Algebras, Particle Phenomenology

Popovych, Roman

279

Forma física da ração e pesos de abate nas características de carcaça de cordeiros em creep feeding  

Microsoft Academic Search

Twenty 3\\/4 Suffolk male lambs were fed ground and pelleted diets and slaughtered at 26 and 28 kg of liveweight. Diets were isoprotein (21% CP) and isoenergetic (2.9 Mcal ME\\/kg DM). Lambs had free entrance on creep feeding, staying with their mothers until reaching slaughter weight. Pelleted diet resulted in higher hot dressing-out percentages (54.18% for pelleted diet and 52.04%

Marcela Abbado Neres; Alda Lúcia Gomes Monteiro; Cledson Augusto Garcia; Ciniro Costa; Mário de Beni Arrigoni; Guilherme Jordão Magalhães Rosa

2001-01-01

280

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 223230. Symmetry Groups and Conservation Laws  

E-print Network

of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bontchev St., Bl.4, 1113 Sofia, Bulgaria E-mails: vassil in structural mechanics ­ the dynamic beam equations of Bernouli­Euler and Timoshenko type governing vibration

Popovych, Roman

281

75 FR 33615 - Draft EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (EPA...  

Federal Register 2010, 2011, 2012, 2013, 2014

...038A). The EPA's draft document and peer review charge are available via the Internet...the EPA Science Advisory Board (SAB) peer review panel for its consideration and...Committee Act, for independent external peer review. The SAB is convening an...

2010-06-14

282

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 116119. Nonlinear Integrable Models with Higher  

E-print Network

determine a submodel in the terminology of [3]). By the way these equations have a long history since [4, 5 an infinite number of conserved currents for them. In this sense the submodel is integrable. The construction­S construction we extend the submodel stated above, [9]. For our extended submodel we can construct (A) (maybe

Popovych, Roman

283

78 FR 12951 - TRICARE; Elimination of the Non-Availability Statement (NAS) Requirement for Non-Emergency...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Non-Emergency Inpatient Mental Health Care AGENCY: Office of the Secretary...non-emergency inpatient mental health care in order for a TRICARE Standard...non-emergency inpatient mental health care for TRICARE Standard...

2013-02-26

284

GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 ?m operation  

Microsoft Academic Search

Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This

Faten Adel Ismail Chaqmaqchee; Simone Mazzucato; Murat Oduncuoglu; Naci Balkan; Yun Sun; Mustafa Gunes; Maxime Hugues; Mark Hopkinson

2011-01-01

285

EFEITOS DO CPPU E DO ÁCIDO GIBERÉLICO NAS CARACTERÍSTICAS DOS CACHOS DA UVA DE MESA CENTENNIAL SEEDLESS  

Microsoft Academic Search

Two trials were conducted in a commercial vineyard, in the region of Jundiaí-SP, with the objective of studying the effects of CPPU and GA3 on the clusters and berries characteristics of Centennial Seedless table grape. In the first experiment, it was used CPPU at 0; 5.0; 7.5; 10.0; 12.5; 15.0 and 17.5mg.L -1 . In a second trial, GA3 was

ERASMO JOSÉ PAIOLI PIRES; RENATO VASCONCELOS BOTELHO; MAURILO MONTEIRO TERRA

286

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 759766 Quantum Groups and Cabibbo Mixing  

E-print Network

-Mann­Okubo (GMO) mass relation for the SU(3) octet baryons 1 2 + derived in a particular version [5] of `diquark. The alternative improved version of GMO for octet baryons is the extremely precise mass sum rule (MSR) obtained-analog (1) yields the familiar [7] Gell-Mann­Okubo (GMO) mass relation MN +M = 3 2M + 1 2M in the `classical

Popovych, Roman

287

Levantamento de características referentes à análise de redes sociais nas comunidades virtuais brasileiras de jogos on-line  

Microsoft Academic Search

Online games have had a noticeable increase in the market. Today, many people interact for hours, with other people, in a virtual gaming world called the Massive Multiplayer Online Role-Playing Game (MMORPGs). The players maintain relationships and build big communities, formed by diverse people who establish links in very different ways. The research analyzed the development of these communities through

Lia C. Rodrigues; Pollyana N. Mustaro

288

PROTOTIPO A PEQUEÑA ESCALA DE UNA NEVERA SOLAR: PRIMEROS RESULTADOS (Prototype in a small scale of a solar refrigerador: first results) CIENCIA Y SOCIEDAD Volumen XXXIII, Número 2 Abril-Junio 2008  

Microsoft Academic Search

With the purpose of verifying the possibility of operation of a solar refrigerador by adsortion with a cooling pair (metanol-activated carbon), we designed and built a prototype in a small scale, simulating the energy received from the sun, by electrical resistances. In the test we performed, a temperature of 4.9 oC was obtained. This result is very promising, in so

Inna Samson; Rodolfo Echarri; Claudio El Hasi

289

Distribution Statement ---Approved for public release, distribution is unlimited. This work was performed under NASA contract no. NAS801100 with the 2 nd Generation Reusable Launch Vehicle  

E-print Network

, in principal, be defined in terms of explicit descriptions of the system nominal and failure modes, in either­based reasoning (MBR), or . implicitly, when used at design time to train or develop algorithms, e.g. neural nets

Pecheur, Charles

290

Influência da radiação solar na distribuição das comunidades vegetais nas áreas livres de gelo da Baía do Almirantado, Ilha Rei George, Antártica  

Microsoft Academic Search

This work had as objective to study the influence of the solar energy in the space distribution of the vegetal communities in the ice-free areas in the Admiralty Bay, King George Island, Antarctica. The Solar Analyst extension was used to generate model of distribution of the global radiation in the area of the Demay point. It was verified that the

Márcio Rocha Francelino

291

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 170175 Towards the Group Classification of Control Systems  

E-print Network

the Group Classification of Control Systems Victor I. LEHENKYI and Joachim RUDOLPH Institute classification for the second-order control systems. 1 Introduction Recently there has been quite a few publications dealing with the symmetries of control systems. Nevertheless, most of them deal with particular

Popovych, Roman

292

Pratt & Whitney/Boeing Engine Validation of Noise Reduction Concepts Final Report for NASA Contract NAS3-97144, Phase 2  

NASA Technical Reports Server (NTRS)

This report presents results of the work completed in Phase 2 of the Engine Validation of Noise Reduction Concepts (EVNRC) contract. The purpose of the program is to validate, through engine testing, advanced noise reduction concepts aimed at reducing engine noise up to 6 EPNdB and improving nacelle suppression by 50 percent relative to 1992 technology. Phase 1 of the program is completed and is summarized in NASA/CR-2014-218088.

Bock, Larry A.; Hauser, Joseph E.; Mathews, Douglas C.; Topol, David A.; Bielak, Gerald W.; Lan, Justin H.; Premo, John W.

2014-01-01

293

SISTEMAS DE COLHEITA DA CANA-DE-AÇÚCAR E ALTERAÇÕES NAS PROPRIEDADES FÍSICAS DE UM SOLO PODZÓLICO AMARELO NO ESTADO DO ESPÍRITO SANTO1  

Microsoft Academic Search

A long term (1989-1994) experiment with sugar cane (RB 739735) was carried out, in Linhares, ES, Brazil, in order to evaluate the effect of two systems of sugar cane harvesting: the first with previous burning (burned cane), and the second with crop residue remaining on the soil surface (green cane), on some physical properties of a tableland Yellow Podzolic soil.

MARCOS BACIS CEDDIA; LÚCIA HELENA CUNHA; DOS ANJOS; EDUARDO LIMA; ALEXANDRE RAVELLI NETO

294

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 767773 Classical Liouville Theory and the Microscopic  

E-print Network

Liouville Theory and the Microscopic Interpretation of Black Hole Entropy Alex GIACOMINI Department E-mail: giacomin@science.unitn.it In this paper we will compute the entropy of a Schwarzschild black a Virasoro algebra with a classical central charge. It is then possible to compute the black hole entropy via

Popovych, Roman

295

Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 616622 Equation for Particles of Spin 3  

E-print Network

gyromagnetic ratio g. 1 Introduction After the discovery of the acausality of the Rarita­Schwinger equation [1, incorrect value of the gyromagnetic ratio etc [2, 3, 4]. In the present paper we propose the equation

Popovych, Roman

296

Growth of InGaAs/GaNAs strain-compensated quantum dot superlattice on GaAs (3 1 1)B by molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

We have studied the structural and optical properties of 10 stacked layers of self-organized In 0.4Ga 0.6As quantum dots (QDs) grown on GaAs (3 1 1)B substrates by atomic hydrogen-assisted radio frequency (RF)-molecular beam epitaxy. A 40 nm-thick GaN 0.007As 0.993 dilute nitride, which is used to cover each QD layer acts as a strain-compensation layer (SCL). The density of strain-compensated In 0.4Ga 0.6As QDs on GaAs (3 1 1)B can be controlled between 2×10 10 and 1×10 11 cm -2 by simply changing the growth temperature. Closely spaced In 0.4Ga 0.6As QDs on GaAs (3 1 1)B shows an ordered structure, in which we observe clear peaks in the two-dimensional fast Fourier transformation image. The temperature dependence of photoluminescence (PL) spectra shows a narrower linewidth over the whole temperature range 30-300 K for strain-compensated QDs owing to better uniformity in the QD size.

Oshima, Ryuji; Shoji, Yasushi; Takata, Ayami; Okada, Yoshitaka

2009-03-01

297

Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 507509. Symmetric Properties of First-Order Equations  

E-print Network

Fmn - i¯m Dm - 1 2 (DmA)2 - 1 2 (DmB)2 - i ¯m Dm + ig(A + iB){ , } + ig(A - iB){¯ , ¯ } + igD[A, B] + 1 2 - iB) = 2, (A + iB) = 2¯ ¯, V = -2i( ¯ + ¯ ), D = -D ¯ + ¯ D , (F + iG) = 2i¯ D + g[¯ , A - iB] , (F - iG) = 2i D + g[, A + iB] , = 1 2 (f + 2iD), ¯ = 1 2 ¯ (f - 2i D), = i¯ D (A - iB

Popovych, Roman

298

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 574577 Generalized Self-Duality in Superfield Formalism  

E-print Network

- i ¯m Dm + ig(A + iB){ , } + ig(A - iB){¯ , ¯ } + 1 2 D2 + 1 2 F2 + 1 2 G2 . (5) The equations of motion of theory (5) are as follows D f + D f + 4g {, ¯ } + {, ¯ } - ig [A - iB, D (A + iB)] + [A + iB, D (A - iB)] = 0, D D (A - iB) - 4ig{ , } - 2g[D, A - iB] = 0, (6) D D (A + iB) - 4ig

Popovych, Roman

299

Passivo ambiental: estudo de caso da Petróleo Brasileiro S.A - Petrobrás. A repercussão ambiental nas demonstrações contábeis, em conseqüência dos acidentes ocorridos  

Microsoft Academic Search

Financial statements are very important for stockholders, investors, suppliers, funders and interested parties to know about the equity situation and result of a company, as well as how it relates to the environment, its commitment to nature and to current legislation. The absence of this information or the inexistence of its segregation can hide the impact of proactive or reactive

Ana Lúcia Bertoli; Maisa de Souza Ribeiro

2006-01-01

300

Magnetotransport study on as-grown and annealed n- and p-type modulation-doped GaInNAs/GaAs strained quantum well structures  

PubMed Central

We report the observation of thermal annealing- and nitrogen-induced effects on electronic transport properties of as-grown and annealed n- and p-type modulation-doped Ga1 - xInxNyAs1 - y (x?=?0.32, y?=?0, 0.009, and 0.012) strained quantum well (QW) structures using magnetotransport measurements. Strong and well-resolved Shubnikov de Haas (SdH) oscillations are observed at magnetic fields as low as 3 T and persist to temperatures as high as 20 K, which are used to determine effective mass, 2D carrier density, and Fermi energy. The analysis of temperature dependence of SdH oscillations revealed that the electron mass enhances with increasing nitrogen content. Furthermore, even the current theory of dilute nitrides does not predict a change in hole effective mass; nitrogen dependency of hole effective mass is found and attributed to both strain- and confinement-induced effects on the valence band. Both electron and hole effective masses are changed after thermal annealing process. Although all samples were doped with the same density, the presence of nitrogen in n-type material gives rise to an enhancement in the 2D electron density compared to the 2D hole density as a result of enhanced effective mass due to the effect of nitrogen on conduction band. Our results reveal that effective mass and 2D carrier density can be tailored by nitrogen composition and thermal annealing-induced effects. PACS 72.00.00; 72.15.Gd; 72.80.Ey PMID:24661541

2014-01-01

301

An estimate of the enroute noise of an advanced turboprop airplane NASA-TM-87302 E-3020 NAS 1.15:87302 HC A02/MF A01  

NASA Technical Reports Server (NTRS)

The enroute noise of an Advanced Turboprop powered aircraft was estimated. The measured noise levels were roughly equivalent in annoyance to the noise 15.24 m from an automobile traveling at 80 km/h. It is felt that these levels would not illicit noise complaints from urban areas during the day but might be a slight annoyance in rural areas or in urban areas at night. Although it is not felt that the enroute noise is a major problem, it is indicated that a reduction in the enroute noise could improve the acceptability of advance turboprop airplanes.

Dittmar, J. H.

1986-01-01

302

Review of the NAS/NRC report: {open_quotes}Groundwater at Yucca Mountain: How high can it rise?{close_quotes}. Special report No. 1  

SciTech Connect

There are three basic and serious problems that produce disagreement with the conclusions and recommendations of the Academy report entitled {open_quotes}Groundwater at Yucca Mountain: How high can it rise?{close_quotes}. These are: First, the report ignores a considerable body of critical data relating to the ages and nature of hydrothermal alterations at the site; second, many of the strong conclusions expressed in the report are not reasonably supported by the evidence presented and, in some cases, are inconsistent with data and results available to the committee but which are not cited or used by them; and finally, there are statements describing field relationships and data that are not consistent with the facts or are made in such a way as to be misleading.

Archambeau, C.B.

1992-12-01

303

Realizacao domestica e escolar de foto e video 3D  

E-print Network

English: Industry does not give attention to the small domestic or professional market of digital technologies for 3D images. What was done on the XX century by using photographic film is not know available to the common people, though the facilities are even better. Some technique developed in Brasil twenty years ago and the use of conventional domestic photo or video cameras allows fot making pictures and films at home by using digital conversions for editing, and two-color goggles. The anaglyphic technique, the same NASA employs to show Mars images to the public, is not employed in Brazil yet. We must analize the reasons for that. Portugues: A industria nao tem dado atencao ao mercado domestico ou profissional de pequena escala nas novas tecnologias digitais para imagem 3D. O que foi feito ao longo do seculo XX usando filme fotografico nao esta hoje ao alcance das pessoas, sendo que a facilidade de uso e muito maior. Tecnicas desenvolvidas no Brasil ha mais de vinte anos, e o uso de simples cameras convenc...

Lunazzi, Jose J

2012-01-01

304

Extensão do WEKA para Métodos de Agrupamento com Restrição de Contigüidade  

Microsoft Academic Search

This work addresses the shortage of open-source data mining tools that implement spatial data mining methods. Therefore, this work presents the development of a WEKA extension for contiguity-constrained clustering method. Resumo. Este trabalho aponta a pouca disponibilidade de ferramentas de mineração de dados de código-aberto que implementam métodos de mineração de dados espaciais. Portanto, o objetivo deste trabalho, para tentar

Carlos Eduardo; R. de Mello; Geraldo Zimbrão da Silva; Jano M. de Souza; Caixa Postal

2007-01-01

305

Ground Software Maintenance Facility (GSMF) user's manual. Appendices NASA-CR-178806 NAS 1.26:178806 Rept-41849-G159-026-App HC A05/MF A01  

NASA Technical Reports Server (NTRS)

Procedures are presented that allow the user to assemble tasks, link, compile, backup the system, generate/establish/print display pages, cancel tasks in memory, and to TET an assembly task without having to enter the commands every time. A list of acronyms is provided. Software identification, payload checkout unit operating system services, data base generation, and MITRA operating procedures are also discussed.

Aquila, V.; Derrig, D.; Griffith, G.

1986-01-01

306

A Pos-Graduacao Nas Ciencias Humanas e o Paradigma da Medicina: A Era da Especializacao. (Post-Graduation in the Human Sciences and the Paradigm of Medicine: The Era of Specialization.)  

ERIC Educational Resources Information Center

Reflects on the current tendency in Brazilian higher education for greater and greater specialization, particularly in human sciences and in medicine. Calls for less specialization and a more historic and general preparation, especially in teacher education. (BT)

Costa, Celio Juvenal

2000-01-01

307

Two Ohio State researchers elected to National Academy of Sciences Two Ohio State professors have been elected to the National Academy of Sciences (NAS), one of the most prestigious  

E-print Network

development partners to commit funds for larger scale trials. Columbus-based pH Matter, Inc., will receive-borne diseases that infect food and fiber-producing animals, companion animals, and humans. Her research focuses on how unique pathogens infect and thrive within primary host defensive white blood cells and cause

308

Determination of N-acetylserotonin and Melatonin Activities in the Pineal Gland, Retina, Harderian Gland, Brain and Serum of Rats and Chickens  

Microsoft Academic Search

An N-acetylserotonin\\/melatonin radioimmunoassay (NAS\\/Mel RIA) and a Mel RIA were developed to measure NAS and Mel contents in tissues of rats and chickens. Anti-NAS and anti-Mel sera were produced by immunization of rabbits with NAS-M-bovine serum albumin (BSA) and Mel-M-BSA, respectively. Anti-NAS serum used in the NAS\\/Mel RIA reacts equally well with NAS and Mel, while anti-Mel serum used in

S. F. Pang; G. M. Brown; L. J. Grota; J. W. Chambers; R. L. Rodman

1977-01-01

309

William H. Press Present position  

E-print Network

of Science, NAS, 2009. Committee on International Security and Arms Control, NAS, 2008­ Computer Science for Council and Officers, NAS, 2005­2006 U.S.-Russia Committee on Strengthening Cooperative Nuclear

Press, William H.

310

Determination and characterization of oxy-naphthenic acids in oilfield wastewater.  

PubMed

Oxy-naphthenic acids (oxy-NAs) are one of the major components of NA mixtures in wastewaters from petroleum industries. The limited available data indicated that oxy-NAs were considered as a potential marker for the degradation of NAs, and some oxy-NAs exhibited endocrine disrupting activities. However, the lack of information on the structures and occurrences of oxy-NAs in oilfield wastewaters limited the interpretations of the biotransformation pathways of NAs and structure-specific toxicity. A sensitive method for simultaneous determination of oxy-NAs together with NAs was developed by combining MAX extraction column and UPLC-ESI(-)-QTOF-MS. The 2000-fold SPE preconcentration step was highly specific for acids and the prewash solvent greatly reduced matrix effects in the UPLC-ESI(-)-QTOF-MS analysis, resulting in an increase in sensitivity down to detection limits in the ng/L range. To provide structural information within each oxy-NA isomer class, a new method was developed by derivatizing oxy-NAs with dansyl chloride by UPLC-ESI(+)-QTOF-MS. The molecular ion dansyl derivatives from the corresponding oxy-NAs and characteristic fragmentation ions, not detected before derivatization, were observed in the extracts of oilfield wastewater, providing evidence that O3-NAs and O4-NAs were mainly composed of OH-NAs and (OH)2-NAs, respectively. Semiquantification of oxy-NAs and NAs in various oilfield wastewaters revealed NAs, O3-NAs, and O4-NAs present at concentrations of 187-397, 44-146, and 40-108 ?g/L, respectively. Significantly different profiles of NA mixtures were observed in petroleum refinery wastewater and oil sands extraction water, but the profile of oxy-NAs was similar to NAs in different wastewaters suggesting the existence of biotransformation between NAs and oxy-NAs in the environment, and hydroxylation could be one of the major biotransformation pathways of NAs. PMID:23859600

Wang, Beili; Wan, Yi; Gao, Yingxin; Yang, Min; Hu, Jianying

2013-08-20

311

aquagym fitness salsa handball tennis de table rugby rock n'roll  

E-print Network

natation randonnées ski escala judo musculation ultimate gi- gong pilates step tennis capoeïra fesses abdos cuisses yoga kung fu basket-ball futsal judo aikid arts du cirque aquagym fitness salsa handball tennis de table rugby rock n'roll badminton volley-ball salsa zumb natation randonnées ski escala judo musculation

Jeanjean, Louis

312

Suporte `a computac~ao orientada aos grupos em sistemas distribuidos tolerantes a faltas  

E-print Network

redes de grande escala geogr´afica. Estas redes destinguem-se das redes locais principalmente pelas suas desempenho aceit´avel sobre este tipo de redes. A grande maioria das redes de grande-escala hoje existentes s~ao constitu´idas por aglomerados de redes locais interligados por redes ponto-a-ponto. Para oferecer comunicac

Rodrigues, Luís E.T.

313

ESTUDIO DEL MECANISMO DE FALLA DE TERRAPLENES DEBIDO A LA INFILTRACIÓN DE AGUAS LLUVIAS MEDIANTE EL MONITOREO DE PRESIONES DE POROS Y CONTENIDOS DE AGUA STUDY OF FAILURE MECHANISM IN EMBANKMENTS INDUCED BY RAINFALL INFILTRATION BY MONITORING PORE WATER PRESSURES AND WATER CONTENTS  

Microsoft Academic Search

Recibido para revisar 27 de Julio de 2006, Aceptado 14 de Noviembre de 2006, Version final 24 de Enero de 2007 RESUMEN: El presente artículo muestra experimentos realizados utilizando modelos a escala para estudiar el proceso de infiltración en terraplenes sometidos a aguas lluvias. Varios modelos a escala fueron construidos usando un suelo arenoso con alto contenido de finos; para

EDWIN GARCÍA; TARO UCHIMURA

2007-01-01

314

Deconstructing Network Attached Storage systems  

Microsoft Academic Search

Network Attached Storage (NAS) has been gaining general acceptance, because it can be managed easily and files shared among many clients, which run different operating systems. The advent of Gigabit Ethernet and high speed transport protocols further facilitates the wide adoption of NAS. A distinct feature of NAS is that NAS involves both network I\\/O and file I\\/O. This paper

Yuhui Deng

2009-01-01

315

QUALIDADE DE PRODUTOS MINIMAMENTE PROCESSADOS E COMERCIALIZADOS EM GÔNDOLAS DE SUPERMERCADOS NAS CIDADES DE LA VRAS - MG , BRASÍLIA - DF E SÃO P AULO - SP Quality of fresh-cut produce commercialized on supermarket shelves in the cities of Lavras-MG, Brasília-DF, and São Paulo-SP  

Microsoft Academic Search

The production of fresh-cut fruits and vegetables has shown an outstanding growth in the latest years, due to the remarkable changes in the consumers' life style, such as family reduction, search for convenience and increased awareness of a wholesome food diet which meets the requirements of food safety. The aim of this work was to characterize the physicochemical and microbiological

Nélio Ranieli; Ferreira de Paula; Eduardo Valério de Barros; Vilas Boas; Luiz José Rodrigues; Rosilane Aparecida Carvalho; Roberta Hilsdorf Piccoli

316

EFECTOS DE LABRANZA Y BIOFERTILIZACIÓN EN PROPIEDADES DEL SUELO QUE AFECTAN A LA SOSTENIBILIDAD DE LA PRODUCCIÓN DE FRIJOL EFFECTS OF TILLAGE AND BIOFERTILIZATION ON THE SOIL PROPERTIES AFFECTING SUSTAINABILITY OF THE DRY BEAN PRODUCTION EFECTOS DA LABRANZA E BIOFERTILIZACIÓN NAS PROPIEDADES DO SOLO QUE AFECTAN A SOSTEÑIBILIDADE DE PRODUCCIÓN DE FRIXOL  

Microsoft Academic Search

Dry beans (Phaseolus vulgaris L.) is an alternative of production in a cereal-legume crop rotation because improves profitability and fixes atmospheric nitrogen to soil. Different tillage practices that leave crop residues on the surface, and minimally alerts composition, structure and natural biodiversity of soil are used to conserve the agriculture ecosystem. Biological fertilizers using vesicular-arbuscular mycorrhizal (Glomus intraradices) constitutes a

J. R. Salinas-García; A. Díaz-Franco; E. Garza-Cano; I. Garza-Cano

2005-01-01

317

CeRRANDo LA BReCHA DIGITAL eN eL PeRÚ: eDUCANDo A PeRSoNAS VIVIeNDo CoN VIH\\/SIDA PARA eVALUAR LA CALIDAD De LA INFoRMACIÓN eN SALUD eN INTeRNeT  

Microsoft Academic Search

SUMMARY People living with HIV\\/AIDS (PLWHA) are increasingly using the Internet to find health information. Global literature about education of PLWHA regarding information and communication technologies (ICTs) is scarce. The objective of this paper is to report the evaluation of a workshop offered to PLWHA to evaluate the quality of the health information available on the Internet. A computer-based workshop

Walter H. Curioso; Katiuska Castillo C; Leslie Soto; David Iglesias Q; Juan Echevarria Z; Eduardo Gotuzzo

2007-01-01

318

A Aplicação e o Conceito de Raça em Saúde Pública: Definições, Controvérsias e Sugestões para Uniformizar sua Utilização nas Pesquisas Biomédicas e na Prática Clínica The Concept of Race in Public Health: Definitions, Controversies and Recommendations to Improve Its Use in Biomedical Research and Clinical Practice  

Microsoft Academic Search

A categorização dos seres humanos em raça e etnia é um dos temas mais controversos e discutidos em medicina. antropologistas e geneticistas acreditam que, do ponto de vista biológico, raças humanas não existem. Para eles, raça é um construto social (baseado em características físicas) que se modifica com o tempo; e etnia um conceito que incorpora na sua definição variáveis

Crésio Alves; Cristina M. M. Fortuna; Maria Betânia; P. Toralles

2005-01-01

319

Fotometria diferencial de estrelas T Tauri  

NASA Astrophysics Data System (ADS)

Neste trabalho apresentamos os resultados preliminares de um monitoramento de estrelas jovens, que pretende ser de longa duração. As estrelas estão em sua maioria localizadas no complexo Lupus-Scorpius. Nosso objetivo principal é o estudo da variabilidade em escalas de tempo de minutos até vários dias para estrelas cujos períodos não estão determinados ou apresentam discrepâncias entre diferentes publicações. A técnica utilizada foi a fotometria diferencial, com exposições de 60s e 90s, com as câmaras CCD SBIG ST7E e ST8E acopladas aos telescópios Schmidt-Cassegrain LX200 (10 e 12 polegadas), instalados na Fundação Planetário da Cidade do Rio de Janeiro. Os primeiros resultados indicam que a técnica é bastante sólida com relação à instabilidade na transparência do céu, mesmo com o uso de telescópios de pequeno porte. Objetos de magnitude 14, no telescópio de 10 polegadas, apresentam dispersões na diferença de magnitudes das comparações, em torno de 0,008mag nas exposições de 60s. Note-se, ainda, que a dispersão pode ser melhorada utilizando-se a técnica de soma de imagens. Destacamos AK Sco, GW Lup, GQ Lup e TW Hya. AK Sco é uma binária que, apesar de ter a sua órbita e período cobertos espectroscopicamente (13,6dias), nunca teve seus eclipses estudados por meio de fotometria. GW Lup não tem período determinado na literatura. Temos acompanhado este objeto há alguns anos, e sugestões de períodos entre 5 e 6 dias têm sido encontradas. O objeto que mereceu maior atenção foi TW Hya por apresentar vários trabalhos fotométricos e espectroscópicos com resultados discrepantes quanto ao período rotacional, que varia de 1,8 a 4,4 dias (Rucinsky & Krautter 1983, A&A 121, 217; Herbst & Koret 1988, AJ 96, 1949; Mekkaden 1988, A&A 340, 135; Batalha et al. 2002, ApJ 580, 343). Dedicamos 13 noites para essa estrela, totalizando cerca de 2.000 pontos na curva de luz. Nossos dados indicam a presença de uma modulação com dois períodos possíveis: 2,2 ou 3,8 dias, além de variações irregulares superpostas. Foram observados, também, dois eventos súbitos, espaçados de uma hora, com amplitudes de 0,05mag e duração de aproximadamente 30 minutos. Admitindo-se que tal modulação seja originada por acréscimo sobre a superfície estelar, dois cenários são possíveis. No caso do menor período, apenas uma mancha quente seria visível. No outro caso, duas manchas seriam necessárias, explicando assim a presença de dois picos ao se colocar os pontos em fase.

Pereira, P. C. R.; Santos-Júnior, J. M.; Cruz, W. S.

2003-08-01

320

Nanotecnología - Duration: 0:30.  

NASA Video Gallery

Piensa en pequeño. No, más pequeño -- piensa en nano. Achícate a la "nano escala", podrías ver los átomos que forman todo Y poder moverlos. Los científicos especialistas en nanotecnología crean nue...

321

Estudio de Exámenes de Detección de Cáncer de Próstata, Pulmón, Colorrectal y Ovarios (PLCO): preguntas y respuestas  

Cancer.gov

El estudio de exámenes de detección PLCO es un estudio a gran escala, aleatorizado, para determinar si el uso de ciertos exámenes selectivos de detección disminuirá el riesgo de morir por esos cuatro tipos de cáncer.

322

UAM. Cartoteca "Rafael Mas". Inventario, 2011 2 UAM. Cartoteca "Rafael Mas". Inventario, 2011 3  

E-print Network

tierra o los cuerpos celestes a cualquier escala, como los mapas y planos en dos y tres dimensiones, las cartas aeronáuticas marinas y celestes, los globos, los bloques-diagramas, los cortes de terreno, las

Autonoma de Madrid, Universidad

323

Contributed Paper Rapid Assessment of Risks to a Mobile Marine  

E-print Network

Protegida a Escala de Ecosistema Resumen: Las redes de ´areas marinas protegidas (AMPs) a escala de pastos marinos: uso de redes, cacer´ia por nativos, pesca con redes de arrastre, tr´afico de nav´ios y riesgo, se tendr´ia que disminuir el uso de redes comerciales y la cacer´ia por nativos en ´areas remotas

Marsh, Helene

324

Identification of Communication and Coordination Issues in the U. S. Air Traffic Control System  

E-print Network

Today’s air traffic control system is approaching the point of saturation, as evidenced by increasing delays across the National Airspace System (NAS). There exists an opportunity to enhance NAS efficiency and reduce ...

Davison, Hayley

325

Scheduling for Parallel Supercomputing: A Historical Perspective of Achievable Utilization  

E-print Network

Scheduling for Parallel Supercomputing: A Historical Perspective of Achievable Utilization James Field, CA 94035-1000 jjones@nas.nasa.gov Abstract.The NAS facility has operated parallel supercomputers supercomputing workload is unrealistic. 1.0 Introduction The Numerical Aerospace Simulation (NAS) supercomputer

Feitelson, Dror

326

Horizontal and vertical structure of the major sporadic sodium layer events observed during ALOHA90  

Microsoft Academic Search

Sporadic Na (Nas) layers have been observed frequently at low- and high-altitude sites primarily in the Northern Hemisphere. Nas layers are very dense and very thin (?1 km FWHM) and can form over periods ranging from a few minutes to several hours. Radar and lidar observations by our group at Arecibo have shown conclusively that Nas layers are linked to

Timothy J. Kane; Chris A. Hostetler; Chester S. Gardner

1991-01-01

327

Intrinsic Job Satisfaction, Overall Satisfaction, and Intention to Leave the Job among Nursing Assistants in Nursing Homes  

ERIC Educational Resources Information Center

Purpose: We examined predictors of intrinsic job satisfaction, overall satisfaction, and intention to leave the job among nursing assistants (NAs). Design and Methods: The study focused on NAs who worked 30 or more hours per week in a nursing home. Data on 2,146 NAs meeting this criterion came from the 2004 National Nursing Assistant Survey, the…

Decker, Frederic H.; Harris-Kojetin, Lauren D.; Bercovitz, Anita

2009-01-01

328

Utopia e Ficção Científica: a \\  

Microsoft Academic Search

Minha geração, cuja infância e adolescência transcorreram nas décadas de 1960 e 1970, assistiu na TV e no cinema muita ficção científica. De certo modo, minhas expectativas sobre o futuro foram moldadas por séries como Jornada nas Estrelas e filmes como Guerra nas Estrelas. As narrativas de ficção científica proliferaram ao nosso redor. E nelas, ingenuamente, eu procurei respostas para

Marcos Lobato Martins

329

CNPq/INPE-LANDSAT system  

NASA Technical Reports Server (NTRS)

The current status of the Brazilian LANDSAT facilities operated by Instituto de Pesquisas Espaciais (INPE) and the results achieved during the period from October 1, 1984 to August 31, 1985 are presented. INPE's Receiving Station at Cuiaba, MT, operates normally the two tracking and receiving systems it has installed, the old one (1973) for Band S and the new one (February 1983) for dual S- and X-band. Both MSS and TM recording capabilities are functional. Support to the NASA Backup Plan for MSS data also remains active. Routine recordings are being made for LANDSAT-5 only, for both MSS and TM. Originally, MSS was recorded over the full acquisition range. However, since December, 1984, due to further reduction of operational expenses, both instruments are being recorded over Brazilian territory only.

Debarrosaguirre, J. L.

1985-01-01

330

Enhanced Electron Precipitation in Brazilian Magnetic Anomaly in association with Sudden Commencement  

NASA Astrophysics Data System (ADS)

Following the first satellite observations of enhanced particle flux in the region of the Brazilian Magnetic Anomaly1,2, various attempts have been made to detect effects associated with the precipitation of radiation belt particles over the region of this anomaly at balloon altitudes3. Since 1968 balloon observations of charged particles and X-rays have been made periodically at the Instituto de Pesquisas Espaciais at São José dos Campos, Brazil. During one of the flights on December 17, 1971, a moderate geomagnetic storm occurred when the balloon was floating at a ceiling altitude of ~3 mbar. Marked changes in the measured particle flux were observed in association with the changes in the magnetic field. As well as pointing out this correspondence we discuss the observational results in relation to observations made on April 6, 1972, during a magnetically quiet period. To our knowledge this is the first direct detection of particle precipitation in the magnetic anomaly at balloon altitudes.

Martin, I. M.; Rai, D. B.; da Costa, J. M.; Palmeira, R.; Trivedi, N. B.

1972-11-01

331

Time-Space Trade-Offs for Longest Common Extensions  

E-print Network

4 sna 6 s a 1 bananas 3 nas 5 s na 7 s 12 / 56 #12;Two Simple Solutions #1: Store nothing T = b a n nas 4 sna 6 s a 1 bananas 3 nas 5 s na 7 s LCE(i, j) = |NCA(i, j)| = 3 13 / 56 #12;Two Simple: Store the suffix tree NCA(2, 4) 2 nas 4 sna 6 s a 1 bananas 3 nas 5 s na 7 s Time: O(1) Space: O(n) LCE

Lonardi, Stefano

332

Current developments in nucleoside/nucleotide analogues for hepatitis B.  

PubMed

There had been remarkable development in nucleos(t)ide analogues (NAs) and evolution in treatment strategies in last 15 years. Currently, there are five NAs available for chronic hepatitis B treatment, namely lamivudine, telbivudine and entecavir (nucleoside analogues), adefovir dipivoxil and tenofovir disoproxil fumarate (nucleotide analogues). The advantages of relatively infrequent side effects and easy administration per oral make NAs popular treatment options. The major drawback of earlier generation NAs is the risk of emergence of drug resistance. Current international guidelines recommend the use of more potent agents with high genetic barriers to resistance including entecavir and tenofovir as first line chronic hepatitis B treatment. However, there is no consensus regarding the subsequent treatment regimens in patients with suboptimal responses to NAs. De novo combination therapy of two NAs, response-guided therapy and roadmap concept in NAs with subsequent switch or add-on therapy can also potentially improve treatment efficacy and avoid resistance. PMID:24787673

Lo, Angeline Oi-Shan; Wong, Grace Lai-Hung

2014-08-01

333

Review of the assessment and management of neonatal abstinence syndrome  

PubMed Central

Neonatal abstinence syndrome (NAS) secondary to in-utero opioid exposure is an increasing problem. Variability in assessment and treatment of NAS has been attributed to the lack of high-quality evidence to guide management of exposed neonates. This systematic review examines available evidence for NAS assessment tools, nonpharmacologic interventions, and pharmacologic management of opioid-exposed infants. There is limited data on the inter-observer reliability of NAS assessment tools due to lack of a standardized approach. In addition, most scales were developed prior to the prevalent use of prescribed prenatal concomitant medications, which can complicate NAS assessment. Nonpharmacologic interventions, particularly breastfeeding, may decrease NAS severity. Opioid medications such as morphine or methadone are recommended as first-line therapy, with phenobarbital or clonidine as second-line adjunctive therapy. Further research is needed to determine best practices for assessment, nonpharmacologic intervention, and pharmacologic management of infants with NAS in order to improve outcomes. PMID:25199822

2014-01-01

334

Nonanastomotic biliary strictures after liver transplantation, part 1: Radiological features and risk factors for early vs. late presentation.  

PubMed

Nonanastomotic biliary strictures (NAS) are a serious complication after orthotopic liver transplantation (OLT). The exact pathogenesis is unclear. Purpose of this study was to identify risk factors for the development of NAS after OLT. A total of 487 adult liver transplants with a median follow-up of 7.9 years were studied. All imaging studies of the biliary tree were reviewed. Cholangiography was routinely performed between postoperative days 10-14 and later on demand. Localization of NAS at first presentation was categorized into 4 anatomical zones of the biliary tree. Severity of NAS was semiquantified as mild, moderate, or severe. Donor, recipient, and surgical characteristics and variables were analyzed to identify risk factors for NAS. NAS developed in 81 livers (16.6%). Thirty-seven (7.3%) were graded as moderate to severe. In 85% of the cases, anatomical localization of NAS was around or below the bifurcation of the common bile duct. A large variation was observed in the time interval between OLT and first presentation of NAS (median 4.1 months; range 0.3-155 months). NAS presenting early (< or =1 year) after OLT were associated with preservation-related risk factors. Cold and warm ischemia times were significantly longer in patients with early NAS compared with NAS presenting late (>1 year) after OLT (694 minutes vs. 490 minutes, P = 0.01, and 57 minutes vs. 53 minutes, P < 0.05, respectively), and early NAS were more frequently located in the central bile ducts. NAS presenting late (>1 year) after OLT were found more frequently in the periphery of the liver and were more frequently associated with immunological factors, such as primary sclerosing cholangitis, as the indication for OLT (24% vs. 45%, P < 0.05). By separating cases of NAS on the basis of the time of presentation after transplantation, we were able to identify differences in risk factors, indicating different pathogenic mechanisms depending on the time of initial presentation. PMID:17457932

Buis, Carlijn I; Verdonk, Robert C; Van der Jagt, Eric J; van der Hilst, Christian S; Slooff, Maarten J H; Haagsma, Elizabeth B; Porte, Robert J

2007-05-01

335

Concurrent observations of auroral activity and a large sporadic sodium layer event during ANLC-93  

NASA Astrophysics Data System (ADS)

Prominent sporadic sodium (Nas) layers, apparently associated with intense auroral activity, were observed during the 1993 Arctic Noctilucent Cloud Campaign (ANLC-93) with an airborne sodium lidar on the August 6 flight near 51°N latitude. The peak density of the Nas layer reached 74,500 cm-3. The zonal extent of the Nas layers exceeded 1600 km. Strong auroral emissions were recorded with an all-sky imager on the aircraft. A Michelson Interferometer was used to measure the intensity of OH nightglow between 85-90 km. OH rotational temperature exhibited no obvious correlation with the Nas layer peak density near 94 km. The data suggest a connection between the Nas layers and auroral electron precipitations. The data also support the conjecture that dust and smoke particles may play a crucial role in the Nas layer formation.

Gu, Y. Y.; Qian, J.; Papen, G. C.; Swenson, G. R.; Espy, P. J.

336

A Regulatory-Based Approach to Safety Analysis of Unmanned Aircraft Systems  

Microsoft Academic Search

Unmanned Aircraft Systems (UAS), the new frontier in civil aviation, add another dimension to the ever-increasing complexity\\u000a of the current National Airspace System (NAS) in the United States. The future inclusion of private and commercial operations\\u000a of the UAS into the NAS, unavoidably, raises safety concerns. As the NAS becomes increasingly more complex and constrained,\\u000a the associated hazard and safety

James T. Luxhøj; Ahmet Öztekin

2009-01-01

337

Horizontal and vertical structure of the major sporadic sodium layer events observed during ALOHA90  

Microsoft Academic Search

Sporadic Na, 'Na(s)' layers have been observed frequently at low- and high-altitude sites primarily in the Northern Hemisphere, Na(s) layers are very dense and very thin (about 1 km FWHM) and can form over periods ranging from a few minutes to several hours. Radar and lidar observations by the group at Arecibo have shown conclusively that Na(s) layers are linked

Timothy J. Kane; Chris A. Hostetler; Chester S. Gardner

1991-01-01

338

This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the  

E-print Network

vertical external-cavity surface-emitting laser (VECSEL) at 1.3 mm. We combined a GaInNAs VECSEL with a GaInNAs semiconductor saturable absorber mirror (SESAM) in a laser cavity. The VECSEL was optically pumped by an 808 nm-performance vertical external-cavity surface-emitting lasers (VECSELs) [3]. We have demonstrated that GaInNAs is also

Keller, Ursula

339

Neutrinos astrofísicos : mecanismo de produção e razão entre sabores.  

E-print Network

??Neutrinos Astrofísicos são produzidos quando prótons ou núcleos, acelerados numa fonte astrofísica, interagem com a matéria nas imediações gerando méons que decaem fracamente produzindo neutrinos.… (more)

Renan Picoreti

2011-01-01

340

Assessment of pesticides effects on soil fauna through ecotoxicological tests with Eisenia andrei (Annelida, Oligochaeta) and natural soil fauna community.  

E-print Network

??Os impactos ambientais relacionados ao uso de agrotóxicos em áreas agrícolas vêm sendo considerados como preocupantes nas últimas décadas, verificando-se efeitos adversos em diferentes níveis… (more)

Maria Edna Tenório Nunes

2010-01-01

341

Desenvolvimento, aplicação e avaliação de um modelo de intervenção positiva para pacientes com miastenia gravis.  

E-print Network

??Essa dissertação objetiva desenvolver, aplicar e avaliar um modelo de intervenção psicológica em grupo baseado nas abordagens cognitivo-comportamental e positiva para pacientes com miastenia gravis.… (more)

Bruna Larissa Seibel

2012-01-01

342

Fiscalização sobre a produção e distribuição de carne bovina em Blumenau em 2006: políticas públicas do setor e desenvolvimento regional.  

E-print Network

??Existem doenças que são transmitidas através de alimentos contaminados. Este trabalho pretende mostrar as conseqüências da falta de fiscalização eficiente da vigilância sanitária nas esferas… (more)

Eliane Maria Maciel Salvalágio

2007-01-01

343

Planejamento, desenvolvimento e estudos de QSAR-2D e QSAR-3D de derivados 5-nitro-2-tiofilidênicos com atividade frente a Staphylococcus aureus multi-resistente (CEB - Clone Endêmico Brasileiro).  

E-print Network

??A reemergência de algumas bactérias Gram-positivas, em particular, do gênero Staphylococcus, como principal foco causador de infecções hospitalares, tem se intensificado nas últimas décadas, e,… (more)

Andrea Masunari

2005-01-01

344

Nonanastomotic biliary strictures after liver transplantation, part 2: Management, outcome, and risk factors for disease progression.  

PubMed

Nonanastomotic biliary strictures (NAS) after orthotopic liver transplantation (OLT) are associated with high retransplant rates. The aim of the present study was to describe the treatment of and identify risk factors for radiological progression of bile duct abnormalities, recurrent cholangitis, biliary cirrhosis, and retransplantation in patients with NAS. We retrospectively studied 81 cases of NAS. Strictures were classified according to severity and location. Management of strictures was recorded. Possible prognostic factors for bacterial cholangitis, radiological progression of strictures, development of severe fibrosis/cirrhosis, graft survival, and patient survival were evaluated. Median follow-up after OLT was 7.9 years. NAS were most prevalent in the extrahepatic bile duct. Twenty-eight patients (35%) underwent some kind of interventional treatment, leading to a marked improvement in biochemistry. Progression of disease was noted in 68% of cases with radiological follow-up. Radiological progression was more prevalent in patients with early NAS and one or more episodes of bacterial cholangitis. Recurrent bacterial cholangitis (>3 episodes) was more prevalent in patients with a hepaticojejunostomy. Severe fibrosis or cirrhosis developed in 23 cases, especially in cases with biliary abnormalities in the periphery of the liver. Graft survival, but not patient survival, was influenced by the presence of NAS. Thirteen patients (16%) were retransplanted for NAS. In conclusion, especially patients with a hepaticojejunostomy, those with an early diagnosis of NAS, and those with NAS presenting at the level of the peripheral branches of the biliary tree, are at risk for progressive disease with severe outcome. PMID:17457935

Verdonk, Robert C; Buis, Carlijn I; van der Jagt, Eric J; Gouw, Annette S H; Limburg, Abraham J; Slooff, Maarten J H; Kleibeuker, Jan H; Porte, Robert J; Haagsma, Elizabeth B

2007-05-01

345

EMENTAS DAS DISCIPLINAS 1) Ementas das Disciplinas Obrigatrias  

E-print Network

Com a Rede de Saúde. Rio de Janeiro: FIOCRUZ, 1995. CASTRO, J. FOME COMO FOR�A SOCIAL: FOME E PAZ. Indicadores de Medida da Magnitude e Insegurança Alimentar no Brasil: Fundamentos para o uso de uma Escala. In

Paraná, Universidade Federal do

346

Estudio del NCI revela que la obesidad extrema puede acortar la esperanza de vida hasta en 14 años  

Cancer.gov

Los adultos con obesidad extrema tienen un mayor riesgo de morir a una edad más joven debido al cáncer y a muchas otras causas entre ellas, enfermedades cardíacas, accidentes cerebrovasculares, diabetes y enfermedades del hígado y los riñones, según los resultados de un análisis de datos de 20 estudios a gran escala realizados en personas de tres países.

347

GMOs and Glyphosate: A Dangerous Combina:on  

E-print Network

of Agriculture Au:sm Prevalence: 6 year olds GMO Roundup Ready Crops · Core crops-90% of the crop by 2010 · "Roundup-ready" weeds quickly evolved ­ EscalaSng use of Roundup, Roundup-ready and 2,4-D resistant corn coming? ­ Bt is a toxin that blows up

Seneff, Stephanie

348

TRANSNACIONALISMO E INCORPORACIÓN LABORAL DE MIGRANTES MEXICANOS EN ESTADOS UNIDOS Y LAS PERSPECTIVAS DE ASCENSO SOCIOECONÓMICO PARA SUS HIJOS  

Microsoft Academic Search

A lo largo de casi todo el siglo XX, en Estados Unidos prevaleció la idea de que los in- migrantes con bajos niveles de capacitación, lógicamente, ocuparían los peldaños más bajos de la escala ocupacional y salarial, pero que, dadas las oportunidades exis- tentes en el país, sus hijos tendrían muchas posibilidades para incorporarse a los estratos medios. A principios

Elaine Levine

349

PROTECCIÓN A LOS MENORES EN LA LEGISLACIÓN CUBANA  

Microsoft Academic Search

El tratamiento a la niñez y la adolescencia a escala internacional necesitan más que protección jurídica, atención especial de los Estados y en el caso específico de Cuba esta protección está garantizada, siendo prioridad del Estado revolucionario el desarrollo integral y multifacético de nuestros Niños, Niñas y Adolescentes. La protección jurídica que en el caso de Cuba se da a

Xiomara Cabrera Cabrera

2012-01-01

350

Caracterización y selección del lugar de nidificación de la grulla cubana (Grus canadensis nesiotes) en los herbazales del Refugio de Fauna El Venero, Cuba  

Microsoft Academic Search

Grus canadensis nesiotes es una subespecie endémica y amenazada de grulla cuyas poblaciones están asociadas a humedales de agua dulce. En este trabajo se caracterizó su lugar de nidificación y se determinó su selección a tres escalas espaciales en los herbazales del Refugio de Fauna El Venero, Cuba, durante los años 2005–2007. Se monitorizaron 26 nidos hasta la eclosión. También

Y. Ferrer Sánchez; D. Denis Ávila; I. Ruiz Companioni

2010-01-01

351

Sostenibilidad de la producción porcina en Cataluña (España). Aplicación del análisis multicriterio  

Microsoft Academic Search

La evaluación de la sostenibilidad en modelos de producción porcina en Cataluña (España), mediante el análisis multicriterio, se estructura en dos partes. Una primera de establecimiento del marco de análisis donde, de forma participativa, se fijan los criterios de evaluación, sus indicadores y las escalas de evaluación. En la segunda se implementa la metología expuesta para evaluar la sostenibilidad de

Ester Comas Argemí; Àngela D. Bosch Serra; Mamen Cuéllar Padilla; Gonzalo Gamboa Jiménez

2012-01-01

352

La ecología y el desarrollo sostenible frente al capitalismo: una contradicción insuperable  

Microsoft Academic Search

Resumen El progresivo deterioro ambiental y la creciente destrucción de los recursos naturales a escala planetaria constituyen una clara evidencia de lo que es capaz de generar un modelo basado exclusivamente en el crecimiento económico y la obtención de beneficios inmediatos, pero también son un signo elocuente de los propios límites que presenta el capitalismo, pues este modo de producción

José Antonio Segrelles

353

The Condor 111(2):314325 The Cooper Ornithological Society 2009  

E-print Network

migratorias (Zonotrichia albicollis, Dendroica coronata y Dendroica striata) en paisajes que variaron en el (Zonotrichia albicollis), yellow-rumped warbler (Dendroica coronata), and Blackpoll warbler (Dendroica striata significativamente relacionadas con la proporción de cosecha a las tres escalas para Z. albicollis; para todas las

Shutler, Dave

354

Estão os Portugueses a ?votar com os pés?? Alguma evidência empírica  

Microsoft Academic Search

Como é sabido, os movimentos migratórios à escala regional são fruto de uma diversidade de factores. Sendo entendidos como uma reacção, por parte da população, a desvantagens (inaceitáveis) de natureza económica apresentadas pela região de origem, estes movimentos demográficos constituem um importante exemplo da chamada ?votação com os pés?. Claramente, a inexistência (ou a mera ineficácia) de políticas regionais que

António Caleiro

2005-01-01

355

Sesso Especial: Novas Tendncias em Modelagem do Sistema Terrestre (New Trends on Land System Modelling) Coordenadores: Gilberto Cmara (INPE) e Giovana Espindola (IPO-GLP/INPE)  

E-print Network

Sessão Especial: Novas Tendências em Modelagem do Sistema Terrestre (New Trends on Land System múltipla escala, obteremos novas informações sobre os processos que comandam as mudanças do sistema

356

Documento vinculado a vertebradosibericos.org -AVES y Atlas Virtual de Aves Terrestres de Espaa BIOGEOGRAFA ECOLGICA DE LA AVIFAUNA TERRESTRE ESPAOLA  

E-print Network

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 19.51 Formaciones arbustivas IIIIIIIIIIIIIIIIIIIIII 5.66 Form. arboladas abiertas IIIIIII 1 distribución a gran escala en la Península Ibérica. Tiene marcadas preferencias por zonas montañosas, con menor gradientes climáticos y de uso de suelo zonas llanas

Carrascal, Luis M.

357

MESTRADO EM MICROBIOLOGIA FBRICAS CELULARES MICROBIANAS Instituto Superior Tcnico  

E-print Network

MESTRADO EM MICROBIOLOGIA FÁBRICAS CELULARES MICROBIANAS ­ Instituto Superior Técnico Objectivos: O microbiologia celular e molecular com as novas abordagens da engenharia metabólica à escala do genoma procariotas e eucariotas: - Estruturas celulares e compartimentalização; - Sistemas de transporte; - Fluxo de

Instituto de Sistemas e Robotica

358

XI INTI International Conference La Plata 2012 Equipo TAG Territorios Posibles UNLP-CONICET y Universidades asociadas del GDRI  

E-print Network

- CONICET EL CRECIMIENTO URBANO Y SU RELACI�N CON LOS PROCESOS TERRITORIALES EN LA "RNU LAS CARTAS-patagónica, tienen un gran atractivo mundial la demanda de tierras en zonas naturales excepcionales o privilegiadas elementos naturales que incluyen las tierras o territorios en venta. En escalas menores, los cambios que se

Paris-Sud XI, Université de

359

Liderança, Coesão e Satisfação em Equipas Desportivas: Um Estudo com Atletas Portugueses de Futebol e Futsal Leadership, Cohesion and Satisfaction in Sporting Teams: A Study with Portuguese Football and Futsal Athletes  

Microsoft Academic Search

Resumo Este trabalho foi realizado com 200 atletas de duas modalidades (futebol e futsal) incluídos em vários escalões desportivos e analisa a liderança dos treinadores e a coesão e satisfação dos praticantes. Para tal, utilizámos um protocolo de avaliação, com instrumentos de avaliação da liderança (Escala Multidimensional de Liderança, que avalia seis dimensões), da coesão (Questionário de Coesão em Equipas

A. Rui Gomes; Ana Patricia Pereira; Ana Raquel Pinheiro

360

Mathematical Modeling of PDGF-Driven Glioblastoma Reveals Optimized  

E-print Network

from glioblastoma (GBM), the most common and malignant primary brain tumor, have very poor survival in the survival of GBM patients (Walker et al., 1980). Dose escala- tion studies demonstrated that survival or survival and are thus not routinely used in the clinic. Three recent advances provide insights into GBM

361

Estimating naphthenic acids concentrations in laboratory-exposed fish and in fish from the wild.  

PubMed

Naphthenic acids (NAs) are the most water-soluble organic components found in the Athabasca oil sands in Alberta, Canada, and these acids are released into aqueous tailing waters as a result of bitumen extraction. Although the toxicity of NAs to fish is well known, there has been no method available to estimate NAs concentrations in fish. This paper describes a newly developed analytical method using single ion monitoring gas chromatography-mass spectrometry (GC-MS) to measure NAs in fish, down to concentrations of approximately 0.1mgkg(-1) of fish flesh. This method was used to measure the uptake and depuration of commercial NAs in laboratory experiments. Exposure of rainbow trout (Oncorhynchus mykiss) to 3mg NAsl(-1) for 9d gave a bioconcentration factor of approximately 2 at pH 8.2. Within 1d after the fish were transferred to NAs-free water, about 95% of the NAs were depurated. In addition, the analytical method was used to determine if NAs were present in four species of wild fish - northern pike (Esox lucius), lake whitefish (Coregonus clupeaformis), white sucker (Catostomus commersoni), walleye (Sander vitreus) - collected from near the oil sands. Flesh samples from 23 wild fish were analyzed, and 18 of these had no detectable NAs. Four fish (one of each species) contained NAs at concentrations from 0.2 to 2.8mgkg(-1). The GC-MS results from one wild fish presented a unique problem. However, with additional work it was concluded that the NAs concentration in this fish was <0.1mgkg(-1). PMID:18667226

Young, Rozlyn F; Wismer, Wendy V; Fedorak, Phillip M

2008-09-01

362

Iron fortification of rice seeds through activation of the nicotianamine synthase gene  

PubMed Central

The most widespread dietary problem in the world is mineral deficiency. We used the nicotianamine synthase (NAS) gene to increase mineral contents in rice grains. Nicotianamine (NA) is a chelator of metals and a key component of metal homeostasis. We isolated activation-tagged mutant lines in which expression of a rice NAS gene, OsNAS3, was increased by introducing 35S enhancer elements. Shoots and roots of the OsNAS3 activation-tagged plants (OsNAS3-D1) accumulated more Fe and Zn. Seeds from our OsNAS3-D1 plants grown on a paddy field contained elevated amounts of Fe (2.9-fold), Zn (2.2-fold), and Cu (1.7-fold). The NA level was increased 9.6-fold in OsNAS3-D1 seeds. Analysis by size exclusion chromatography coupled with inductively coupled plasma mass spectroscopy showed that WT and OsNAS3-D1 seeds contained equal amounts of Fe bound to IP6, whereas OsNAS3-D1 had 7-fold more Fe bound to a low molecular mass, which was likely NA. Furthermore, this activation led to increased tolerance to Fe and Zn deficiencies and to excess metal (Zn, Cu, and Ni) toxicities. In contrast, disruption of OsNAS3 caused an opposite phenotype. To test the bioavailability of Fe, we fed anemic mice with either engineered or WT seeds for 4 weeks and measured their concentrations of hemoglobin and hematocrit. Mice fed with engineered seeds recovered to normal levels of hemoglobin and hematocrit within 2 weeks, whereas those that ate WT seeds remained anemic. Our results suggest that an increase in bioavailable mineral content in rice grains can be achieved by enhancing NAS expression. PMID:20080803

Lee, Sichul; Jeon, Un Sil; Lee, Seung Jin; Kim, Yoon-Keun; Persson, Daniel Pergament; Husted, Søren; Schjørring, Jan K.; Kakei, Yusuke; Masuda, Hiroshi; Nishizawa, Naoko K.; An, Gynheung

2009-01-01

363

Crianças Paulistas: diferenças raciais ao nascer e ao morrer  

Microsoft Academic Search

A desigualdade em saúde é um tema tradicional nas pesquisas demográficas e epidemiológicas, já que os eventos dos quais elas se ocupam são fortemente condicionados pelo modelo de desenvolvimento de um país que conforma essas desigualdades, que se apresentam nas mais diversas dimensões: classes sociais, frações de classe, gênero, etnias\\/raças. Entretanto, uma das variáveis menos utilizadas nos estudos sobre diferenciais

Estela M. García; Pinto da Cunha

364

78 FR 22189 - Establishment of Area Navigation (RNAV) Routes; OR  

Federal Register 2010, 2011, 2012, 2013, 2014

...in the National Airspace System (NAS) and provides continued en route navigation guidance in the affected airspace. DATES: Effective...expands the use of RNAV within the NAS, and provides for continued en route navigation guidance in a portion of Seattle Air Route...

2013-04-15

365

75 FR 19212 - Modification of Class E Airspace; Oxnard, CA  

Federal Register 2010, 2011, 2012, 2013, 2014

...action also makes a minor change to the name and geographic coordinates of Point Mugu NAS, Oxnard, CA...above the surface for Point Mugu NAS, Oxnard, CA...airspace. This action also changes the name from Point Mugu NAWS, to Point...

2010-04-14

366

N-Acetyl-Serotonin Offers Neuroprotection through Inhibiting Mitochondrial Death Pathways and Autophagic Activation in Experimental Models of Ischemic Injury  

PubMed Central

N-acetylserotonin (NAS) is an immediate precursor of melatonin, which we have reported is neuroprotective against ischemic injury. Here we test whether NAS is a potential neuroprotective agent in experimental models of ischemic injury. We demonstrate that NAS inhibits cell death induced by oxygen–glucose deprivation or H2O2 in primary cerebrocortical neurons and primary hippocampal neurons in vitro, and organotypic hippocampal slice cultures ex vivo and reduces hypoxia/ischemia injury in the middle cerebral artery occlusion mouse model of cerebral ischemia in vivo. We find that NAS is neuroprotective by inhibiting the mitochondrial cell death pathway and the autophagic cell death pathway. The neuroprotective effects of NAS may result from the influence of mitochondrial permeability transition pore opening, mitochondrial fragmentation, and inhibition of the subsequent release of apoptogenic factors cytochrome c, Smac, and apoptosis-inducing factor from mitochondria to cytoplasm, and activation of caspase-3, -9, as well as the suppression of the activation of autophagy under stress conditions by increasing LC3-II and Beclin-1 levels and decreasing p62 level. However, NAS, unlike melatonin, does not provide neuroprotection through the activation of melatonin receptor 1A. We demonstrate that NAS reaches the brain subsequent to intraperitoneal injection using liquid chromatography/mass spectrometry analysis. Given that it occurs naturally and has low toxicity, NAS, like melatonin, has potential as a novel therapy for ischemic injury. PMID:24553937

Zhou, Hua; Wang, Jian; Jiang, Jiying; Stavrovskaya, Irina G.; Li, Mingchang; Li, Wei; Wu, Qiaofeng; Zhang, Xinmu; Luo, Chengliang; Zhou, Shuanhu; Sirianni, Ana C.; Sarkar, Sovan; Kristal, Bruce S.; Friedlander, Robert M.

2014-01-01

367

Work domain analysis for air traffic controller weather displays  

Microsoft Academic Search

Introduction: Adverse weather conditions have a major impact on National Airspace System (NAS) operations. They create safety hazards for pilots, constrain the usable airspace for air traffic control (ATC), and reduce the overall capacity of the NAS. A system-wide dissemination of weather information to controllers could theoretically improve safety and efficiency. Problem: However, it is currently unclear what weather information

Ulf Ahlstrom

2005-01-01

368

78 FR 23329 - Aircraft Access to SWIM Working Group Meeting  

Federal Register 2010, 2011, 2012, 2013, 2014

...participate in an Aircraft Access to SWIM Working Group...May 1, 2013. Aircraft Access to SWIM The FAA's Next...modernization of our National Airspace System (NAS). It is...the NAS. The Aircraft Access to SWIM (AAtS)...

2013-04-18

369

Impacts of new agents for multiple myeloma on development of secondary myelodysplastic syndrome and acute myeloid leukemia.  

PubMed

The use of new agents (NAs) such as bortezomib, thalidomide, and lenalidomide has extended the survival of patients with multiple myeloma (MM). However, whether long-term treatment using NAs may increase the risk of second primary malignancies is a concern. Three hundred and thirty-three patients with MM were treated at our hospital from 1998 to 2013. Additional chromosomal abnormalities (CAs), associated with secondary myelodysplastic syndrome/acute myeloid leukemia, were observed in 13 of 152 users of NAs, but in 38 of 181 non-users of NAs. The cumulative CA incidence was higher in non-users of NAs. The CAs frequently observed were 13q-, 20q-, +8 in users of NAs, while -5/5q- and -7/7q- were detected in non-users of NAs. The total dose and treatment period of NAs did not differ between CAs-positive and -negative patients. However, a higher dose of melphalan was observed to have been used in patients who had CAs. Longer follow-up periods are necessary for an accurate risk assessment. PMID:24850453

Hamano, Airi; Shingaki, Sumito; Abe, Yu; Miyazaki, Kanji; Sekine, Rieko; Nakagawa, Yasunori; Tsukada, Nobuhiro; Hattori, Yutaka; Suzuki, Kenshi

2014-04-01

370

LIFE Economics and Delivery Pathway Presentation to  

E-print Network

LIFE Economics and Delivery Pathway Presentation to National Research Council's review gain may outweigh benefits LIFE Point Design Anklam--NAS/NAE, January 29, 2011NIF-0111-20828s2.ppt 3--NAS/NAE, January 29, 2011NIF-0111-20828s2.ppt 5 #12;At the top level, LIFE plant can be grouped into 8 functional

371

"What Does Bowdoin Teach"? A Dialogue between Wood and Klingenstein  

ERIC Educational Resources Information Center

This article is an exchange of ideas between Peter Wood, President of the National Association of Scholars (NAS), and Tom Klingerstein, Chairman of the Claremont Institute and NAS Board Director, on the study "What Does Bowdoin Teach? How a Contemporary Liberal Arts College Shapes Students" (by Peter Wood and Michael Toscano). This…

Wood, Peter; Klingenstein, Tom

2013-01-01

372

Application performance analysis on Pilatus The US group at CSCS performed a set of benchmarks on Pilatus, using the three  

E-print Network

by the scientific community and parallel benchmarks. Information on the cluster and the processors · Vendor are implemented, the performance doesn't depend on the compiler used. #12;NAS Parallel Benchmarks (NPB) The NAS Parallel Benchmarks (NPB) are a small set of programs designed to evaluate the performance

373

de recherche ISSN0249-6399ISRNINRIA/RR--6945--FR+ENG  

E-print Network

les NPB (Nas Parallel Benchmarks) valident notre approche qui permet de r´eduire le nombre de retour layer on Grid'5000, the French research grid, using MPICH2. The results on the NPB (NAS Parallel Benchmarks) validate our architecture that reduces the number of idle timeout and the number of long

Paris-Sud XI, Université de

374

http://www.cse.wustl.edu/~jain/cse567-06/ftp/processor_workloads/inde... 1 of 14 A Survey Paper on Processor Workloads  

E-print Network

, Fhourstone, SPEC CPU, SiSoft Sandra, LINPACK, LAPACK, Lawrence Livermore Loops, NAS Parallel Benchmarks, 3.3 Lawrence Livermore Loops 4.4 NAS Parallel Benchmarks #12;http://www.cse.wustl.edu/~jain/cse567-06/ftp to compare them. Benchmarks have been developed to measure performance of processors and rank them among

Jain, Raj

375

ISSN0249-0803ISRNINRIA/RT--0353--FR+ENG INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE  

E-print Network

for basic arithmetic operations. Then we study a Java implementation of the Nas Parallel Benchmarks, using une impl´ementation Java des Nas Parallel Benchmarks avec l'intergiciel ProActive pour la distribution Collection. We first perform some micro benchmarks for various JVMs, showing the overall good performance

Paris-Sud XI, Université de

376

Understanding and Mitigating Multicore Performance Issues on the AMD OpteronTM Architecture  

E-print Network

of microbenchmarks such as STREAM, application kernels such as the NAS Parallel Benchmarks, and full application to the NAS Parallel Benchmarks to dramatically improve their performance.1 Introduction Recent trends codes that comprise the NERSC-5 SSP benchmark suite. We explore compiler options and software

Geddes, Cameron Guy Robinson

377

The Predictive Validity of Infant Assessments in Rural Guatemala.  

ERIC Educational Resources Information Center

The behavioral development of rural Guatemalan infants was assessed shortly after birth on a Neonatal Assessment Scale (NAS) and at 6-, 15-, and 24-months-of-age on a Composite Infant Scale (CIS). Summary variables based on NAS performance poorly predicted later assessed performance even as recently as six months after birth. The CIS modestly…

Lasky, Robert E.; And Others

1981-01-01

378

Coordination between carbon and nitrogen metabolism in nitrogen fixing bean nodules  

Technology Transfer Automated Retrieval System (TEKTRAN)

A cDNA clone of asparagine synthetase (AS) called PvNAS2 and two different cDNA clones of PvNADH-GOGAT were isolated from bean nodules. Southern blot analysis indicated that a small gene family encodes AS. Northern analysis demonstrated that PvNAS2 expression is induced in nodules during the early d...

379

Human Embryonic Stem Cell Research: An Argument for National Research Review  

Microsoft Academic Search

The US National Academy of Sciences (NAS) recently published voluntary guidelines for human embryonic stem (hES) cell research. The NAS guidelines propose two levels of oversight. At the local level, research institutions are to create Embryonic Stem Cell Research Oversight (ESCRO) committees with a mandate to assess the scientific merit and ethical acceptability of hES cell research. At the national

FRANÇOISE BAYLIS; JASON SCOTT ROBERT

2006-01-01

380

Scientific drug information in newspapers: sensationalism and low quality. The example of therapeutic use of cannabinoids  

Microsoft Academic Search

Objective: We aimed to analyse the quality of newspaper articles (NAs) concerning the therapeutic use of cannabis published in Spanish newspapers. Methods: A preliminary questionnaire of the Index of Scientific Quality was used (scores ranged from 0 (no misleading) to 14 (misinformation in each item)). Results: Of the 29 NAs analysed, 16 (55.2%) were scored as 4 or lower, and

Eva Montané; Marta Duran; Dolors Capellà; Albert Figueras

2005-01-01

381

Numerical Aerodynamic Simulation  

NASA Technical Reports Server (NTRS)

An overview of historical and current numerical aerodynamic simulation (NAS) is given. The capabilities and goals of the Numerical Aerodynamic Simulation Facility are outlined. Emphasis is given to numerical flow visualization and its applications to structural analysis of aircraft and spacecraft bodies. The uses of NAS in computational chemistry, engine design, and galactic evolution are mentioned.

1989-01-01

382

Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta.  

PubMed

Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is able to tolerate five model NAs (cyclohexanecarboxylic acid, cyclohexaneacetic acid, cyclohexanepropionic acid, cyclohexanebutyric acid and 1,2,3,4-tetrahydro-2-naphthoic acid) at 300mgL(-1), a level which exceeds that of any single or combination of NAs typically found in tailings ponds. Moreover, we show that D. tertiolecta can metabolize four of the model NAs. Analysis of NA-amended cultures of D. tertiolecta via low resolution gas chromatography-mass spectrometry allowed us to quantify decreasing NA levels, identify metabolites, and formulate putative mechanisms of biodegradation. Degradation of cyclohexanebutyric acid and cyclohexanepropionic acid proceeded via ?-oxidation and resulted in the transient accumulation of cyclohexaneacetic acid and cyclohexanecarboxylic acid, respectively. Cyclohexanecarboxylic acid was metabolized via 1-cyclohexenecarboxylic acid suggesting that further degradation may occur by step-wise ?-oxidation. When D. tertiolecta was inoculated in the presence of oil sands tailings water from the Athabasca region, biodegradation of single-ring NAs was observed relative to controls. This result corroborates the trend we observed with the single-ring model NAs. PMID:21459409

Quesnel, Dean M; Bhaskar, Iyswarya M; Gieg, Lisa M; Chua, Gordon

2011-07-01

383

Bold Plans for School Restructuring: The New American Schools Designs.  

ERIC Educational Resources Information Center

In 1991, the New American Schools (NAS) Development Corporation was founded by a group of business and foundation leaders interested in investing in innovative designs for school transformation. This book describes the first 3 years of development and evaluation of 9 NAS whole-school restructuring designs. The designs were very diverse, as were…

Stringfield, Sam, Ed.; Ross, Steven, M., Ed.; Smith, Lana, Ed.

384

Wake turbulence avoidance automation: Evaluation of feasibility and impact  

Microsoft Academic Search

Wake turbulence encounters are a significant concern to pilots flying in the National Airspace System (NAS). The MITRE Corporation's Center for Advanced Aviation System Development (CAASD) has worked with the Federal Aviation Administration (FAA) to increase efficiency and capacity in the NAS that will come with the FAA's Next Generation Air Transportation System (NextGen). By increasing efficiency and capacity, there

Steven L. Estes; Marshall E. Koch; Clark R. Lunsford; Andrew S. Mendolia

2011-01-01

385

77 FR 48469 - Airworthiness Directives; Airbus Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...Seals with Part Number (P/N) MS28775-XXX or a Part Number That Cannot Be Identified...the seals installed have P/N MS28775-XXX or a part number that cannot be identified...using a new O- ring seal P/N NAS1611-XXX or P/N NAS1611-XXXA, in...

2012-08-14

386

78 FR 27015 - Airworthiness Directives; Airbus Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...Seals with Part Number (P/N) MS28775-XXX or a Part Number that Cannot Be Identified...the seals installed have P/N MS28775-XXX or a part number that cannot be identified...using a new O- ring seal P/N NAS1611-XXX or P/N NAS1611-XXXA, in...

2013-05-09

387

The Future of the National Association of Scholars  

ERIC Educational Resources Information Center

The National Association of Scholars (NAS) today is focused more than ever on public controversies and on public tools of communication. Where once NAS members were primarily concerned with debates within the academy, now they are equally concerned with debates about the academy. If the topics they address have changed, so too have the means by…

Wood, Peter

2012-01-01

388

272 JOURNAL OF DISPLAY TECHNOLOGY, VOL. 9, NO. 4, APRIL 2013 First-Principle Electronic Properties of Dilute-As  

E-print Network

analysis shows that the dilute-As GaNAs alloy exhibits the direct band gap properties. The dilute-As Ga. Minimal interband Auger recombination is also suggested for the dilute-As GaNAs alloy attributing to the off-resonance con- dition for this process. Index Terms--Auger recombination, band parameters, band

Gilchrist, James F.

389

Model development for naphthenic acids ozonation process.  

PubMed

Naphthenic acids (NAs) are toxic constituents of oil sands process-affected water (OSPW) which is generated during the extraction of bitumen from oil sands. NAs consist mainly of carboxylic acids which are generally biorefractory. For the treatment of OSPW, ozonation is a very beneficial method. It can significantly reduce the concentration of NAs and it can also convert NAs from biorefractory to biodegradable. In this study, a factorial design (2(4)) was used for the ozonation of OSPW to study the influences of the operating parameters (ozone concentration, oxygen/ozone flow rate, pH, and mixing) on the removal of a model NAs in a semi-batch reactor. It was found that ozone concentration had the most significant effect on the NAs concentration compared to other parameters. An empirical model was developed to correlate the concentration of NAs with ozone concentration, oxygen/ozone flow rate, and pH. In addition, a theoretical analysis was conducted to gain the insight into the relationship between the removal of NAs and the operating parameters. PMID:25189805

Al Jibouri, Ali Kamel H; Wu, Jiangning

2015-02-01

390

ARTICLE doi:10.1038/nature13793 Artificial sweeteners induce glucose  

E-print Network

introduced into commonly consumed foods such as diet sodas, cereals and sugar-free desserts, and are being Elinav1 Non-caloric artificial sweeteners (NAS) are among the most widely used food additives worldwide for providing sweet taste to foods without the associated high energy content of caloric sugars. NAS consumption

Gleeson, Joseph G.

391

Abstract This paper addresses the following key questions in the discussion on the integration of renewable energy  

E-print Network

, lithium ion (Li-ion) batteries, pumped hydro energy storage (PH), and demand response (DR). Hybrid, NaS battery, Li-Ion battery, pumped-hydro energy storage, demand response, hybrid energy storage. The technologies considered in this study include conventional turbines (CT), sodium sulfur (NaS) batteries

392

1EV GaN[subscript x]As[subscript 1-x-y]Sb[subscript y] material for lattice-matched III-V solar cell implementation on GaAs and Ge  

E-print Network

The effect of different arsenic species (As[subscript 2] or As[subscript 4]) on the quality of molecular beam epitaxy (MBE) grown GaNAsSb materials (samples A and B) and GaAs/ GaNAsSb/GaAs p+n-n+ devices (samples C and D) ...

Yoon, Soon Fatt

393

The USAF Phillips Laboratory sodium-sulfur battery technology program: Results and status  

NASA Technical Reports Server (NTRS)

Tests performed on NaS batteries are reported. The results of safety and abuse testing, shock and vibration tests, cell failure on warm-up, freeze thaw, overtemperature conditions, electrolyte fracture, overdischarge, and short circuit tests are presented along with GEO and LEO cycle tests and the status of the NaS cell flight tests.

Rainbow, Marc E.; Somerville, Andrew

1996-01-01

394

Re-analysis of the nuclear winter phenomenon  

Microsoft Academic Search

Summary An analysis of the report of the (U.S.) National Academy of Sciences (NAS) on atmospheric effects of a nuclear exchange leads to conclusions that differ from those of the NAS and of the earlier “TTAPS” and “AMBIO” studies. Any cooling of the earth's surface is likely to beshort-lived because of rapid removal of the smoke clouds originating from nuclear

S. F. Singer

1988-01-01

395

Making the Case for New Research to Support the Integration of Small Unmanned Aircraft Systems into the National Airspace System  

NASA Technical Reports Server (NTRS)

This paper describes the current state of sUAS regulation, their technical capabilities and the latest technologies that will allow for sUAS NAS integration. The research that is needed to demonstrate sUAS NAS integration capability is identified, and recommendations for conducting this necessary research are suggested.

McAdaragh, Raymon M.; Comstock, James R., Jr.; Ghatas, Rania W.; Burdette, Daniel W.; Trujillo, Anna C.

2014-01-01

396

Comparison of Vehicle Efficiency Technology Attributes and Synergy Estimates  

Microsoft Academic Search

Analyzing the future fuel economy of light-duty vehicles (LDVs) requires detailed knowledge of the vehicle technologies available to improve LDV fuel economy. The National Highway Transportation Safety Administration (NHTSA) has been relying on technology data from a 2001 National Academy of Sciences (NAS) study (NAS 2001) on corporate average fuel economy (CAFE) standards, but the technology parameters were updated in

Duleep

2011-01-01

397

A COMPLEXIDADE EM GEOGRAFIA  

Microsoft Academic Search

Muitos de nós, nas suas infâncias, sucumbimos à curiosidade, achando que valia o risco de apanharmos umas palmadas correctivas, e desmontámos o brinquedo novo que tínhamos acabado de receber, só para tentar perceber como aquelas peças se encaixavam umas-nas-outras e de forma articulada permitiam ao brinquedo funcionar? Pois é, apesar de haver alguns menos confessos, a verdade é que passados

JORGE ROCHA; PAULO MORGADO SOUSA

398

Effects of exposure to naphthenic acids in tree swallows (Tachycineta bicolor) on the Athabasca oil sands, Alberta, Canada.  

PubMed

Naphthenic acids (NAs) are a group of carboxylic acids that are of particular concern to the steadily growing oil sands mining industry of Alberta, Canada, because they become highly concentrated in the water used for oil sands extraction and are toxic to aquatic biota and mammals. Upon mine closure, vast amounts of process-affected water will need to be reclaimed and proven safe for wildlife colonizing reclaimed areas. The effects of exposure to NAs have not been investigated in avian species. To address this void, tree swallow (Tachycineta bicolor) nestlings were dosed with NAs while being reared normally by their free-ranging parents on a site in the vicinity of the oil sands. Nestlings received 1.5 mg NAs/day (approximately 0.075 g/kg body mass) from d 7 to d 13 of age, which represented a 10-fold "worst exposure" scenario. Nestling growth, hematocrit, blood biochemistry, organ weights, and ethoxyresorufin O-deethylase (EROD) activity were unaffected by NAs. The only change detected on histopathological evaluation of major organs was an increase in extramedullary erythropoiesis in the liver. These findings indicate that nestling tree swallows can successfully tolerate short-term exposures to environmentally realistic concentrations of NAs. However, this study did not investigate the chronic or reproductive toxicity of NAs. More research needs to be conducted to complete this initial assessment, to determine environmental risks on reclaimed areas where birds will be breeding and where their exposure to NAs could extend for several weeks. PMID:17573632

Gentes, Marie-Line; Waldner, Cheryl; Papp, Zsuzsanna; Smits, Judit E G

2007-07-01

399

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles. Volume 1, Cell and battery safety  

SciTech Connect

This report is the first of four volumes that identify and assess the environmental, health, and safety issues involved in using sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles that may affect the commercialization of Na/S batteries. This and the other reports on recycling, shipping, and vehicle safety are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD&D) program for Na/S battery technology. The reports review the status of Na/S battery RD&D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers cell design and engineering as the basis of safety for Na/S batteries and describes and assesses the potential chemical, electrical, and thermal hazards and risks of Na/S cells and batteries as well as the RD&D performed, under way, or to address these hazards and risks. The report is based on a review of the literature and on discussions with experts at DOE, national laboratories and agencies, universities, and private industry. Subsequent volumes will address environmental, health, and safety issues involved in shipping cells and batteries, using batteries to propel electric vehicles, and recycling and disposing of spent batteries. The remainder of this volume is divided into two major sections on safety at the cell and battery levels. The section on Na/S cells describes major component and potential failure modes, design, life testing and failure testing, thermal cycling, and the safety status of Na/S cells. The section on batteries describes battery design, testing, and safety status. Additional EH&S information on Na/S batteries is provided in the appendices.

Ohi, J.M.

1992-09-01

400

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles  

SciTech Connect

This report is the first of four volumes that identify and assess the environmental, health, and safety issues involved in using sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles that may affect the commercialization of Na/S batteries. This and the other reports on recycling, shipping, and vehicle safety are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD D) program for Na/S battery technology. The reports review the status of Na/S battery RD D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers cell design and engineering as the basis of safety for Na/S batteries and describes and assesses the potential chemical, electrical, and thermal hazards and risks of Na/S cells and batteries as well as the RD D performed, under way, or to address these hazards and risks. The report is based on a review of the literature and on discussions with experts at DOE, national laboratories and agencies, universities, and private industry. Subsequent volumes will address environmental, health, and safety issues involved in shipping cells and batteries, using batteries to propel electric vehicles, and recycling and disposing of spent batteries. The remainder of this volume is divided into two major sections on safety at the cell and battery levels. The section on Na/S cells describes major component and potential failure modes, design, life testing and failure testing, thermal cycling, and the safety status of Na/S cells. The section on batteries describes battery design, testing, and safety status. Additional EH S information on Na/S batteries is provided in the appendices.

Ohi, J.M.

1992-09-01

401

Is Roux-en-Y choledochojejunostomy an independent risk factor for nonanastomotic biliary strictures after liver transplantation?  

PubMed

Biliary reconstruction using Roux-en-Y choledochojejunostomy has been suggested as a risk factor for the development of nonanastomotic biliary strictures (NAS) after liver transplantation. Roux-en-Y reconstruction, however, is preferentially used in patients transplanted for primary sclerosing cholangitis (PSC), and the disease itself is also associated with a higher incidence of NAS. The aim of this study was to determine whether Roux-en-Y reconstruction is really an independent risk factor for NAS. A series of 486 consecutive adult liver transplants were studied. Biliary reconstruction in patients transplanted for PSC was either by Roux-en-Y choledochojejunostomy or by duct-to-duct anastomosis, depending on the quality of the recipient's extrahepatic bile duct. Univariate and multivariate statistical analyses were used to identify risk factors for the development of NAS. The overall incidence of NAS was 16.5% (80/486). In univariate analyses, the following variables were significantly associated with NAS: PSC as the indication for transplantation, type of biliary reconstruction (Roux-en-Y versus duct-to-duct), and postoperative cytomegalovirus infection. After multivariate logistic regression analysis, PSC as the indication for transplantation (odds ratio, 2.813; 95% confidence interval, 1.624-4.875; P < 0.001) and postoperative cytomegalovirus infection (odds ratio, 2.098; 95% confidence interval, 1.266-3.477; P = 0.004) remained as independent risk factors for NAS. Biliary reconstruction using Roux-en-Y choledochojejunostomy was not identified as an independent risk factor for NAS. In conclusion, the association between Roux-en-Y choledochojejunostomy and NAS observed in previous studies can be explained by the more frequent use of Roux-en-Y reconstruction in patients with PSC. Roux-en-Y reconstruction itself is not an independent risk factor for NAS. Liver Transpl 15:924-930, 2009. (c) 2009 AASLD. PMID:19642122

Hoekstra, Harm; Buis, Carlijn I; Verdonk, Robert C; van der Hilst, Christian S; van der Jagt, Eric J; Haagsma, Elizabeth B; Porte, Robert J

2009-08-01

402

Effect of molecular structure on the relative reactivity of naphthenic acids in the UV/H?O? advanced oxidation process.  

PubMed

The large volume of oil sands process-affected water (OSPW) produced by the oil sands industry in Northern Alberta, Canada, is an environmental concern. The toxicity of OSPW has been attributed to a complex mixture of naturally occurring acids, including naphthenic acids (NAs). Highly cyclic or branched NAs are highly biopersistent in tailings ponds, thus understanding structure-reactivity relationship for NAs is very important for OSPW reclamation. In this study, we hypothesized that large, branched and cyclic NAs may be better oxidized in the UV/H(2)O(2) process than small, linear and acyclic NAs. Relative rate measurements using binary mixtures of model NA compounds confirmed that reactivity favored compounds with more carbons, and also favored NAs with one saturated ring, relative to the corresponding linear NA. However, for model compound with three rings, no increased reactivity was observed relative to monocyclic NA. UV/H(2)O(2) treatment of OSPW confirmed our findings with model compounds, indicating that the compounds with more carbons are favored for degradation. However, increasing the number of rings (or double bond equivalents) in OSPW NAs did not show any clear structure-reactivity. Microbial degradation studies of the UV/H(2)O(2) treated OSPW should be conducted to examine the overall benefit of this treatment for the real applications. PMID:22934634

Afzal, Atefeh; Drzewicz, Przemys?aw; Pérez-Estrada, Leónidas A; Chen, Yuan; Martin, Jonathan W; Gamal El-Din, Mohamed

2012-10-01

403

Making Each Other’s Daily Life: Nurse Assistants’ Experiences and Knowledge on Developing a Meaningful Daily Life in Nursing Homes  

PubMed Central

Background: In a larger action research project, guidelines were generated for how a meaningful daily life could be developed for older persons. In this study, we focused on the nurse assistants’ (NAs) perspectives, as their knowledge is essential for a well-functioning team and quality of care. The aim was to learn from NAs’ experiences and knowledge about how to develop a meaningful daily life for older persons in nursing homes and the meaning NAs ascribe to their work. Methods: The project is based on Participatory and Appreciative Action and Reflection. Data were generated through interviews, participating observations and informal conversations with 27 NAs working in nursing homes in Sweden, and a thematic analysis was used. Result: NAs developed a meaningful daily life by sensing and finding the “right” way of being (Theme 1). They sense and read the older person in order to judge how the person was feeling (Theme 2). They adapt to the older person (Theme 3) and share their daily life (Theme 4). NAs use emotional involvement to develop a meaningful daily life for the older person and meaning in their own work (Theme 5), ultimately making each other’s daily lives meaningful. Conclusion: It was obvious that NAs based the development of a meaningful daily life on different forms of knowledge: the oreticaland practical knowledge, and practical wisdom, all of which are intertwined. These results could be used within the team to constitute a meaningful daily life for older persons in nursing homes. PMID:25246997

James, Inger; Fredriksson, Carin; Wahlström, Catrin; Kihlgren, Annica; Blomberg, Karin

2014-01-01

404

Harnessing oil sands microbial communities for use in ex situ naphthenic acid bioremediation.  

PubMed

The caustic hot water extraction process used to release bitumen from the Alberta oil sands generates large volumes of tailings waste, or oil sands process water (OSPW). OSPW contains several components of environmental concern including diluents, polyaromatic hydrocarbons, heavy metals, and naphthenic acids (NAs); the latter are of particular concern as they are acutely toxic to aquatic organisms and mammals. Studies have demonstrated that the naturally occurring OSPW bacteria are capable of metabolizing the NAs. However, this in situ process takes place over hundreds of years, and is incomplete, leaving a recalcitrant fraction of NAs intact. In this study we explore options for recovering and harnessing the naturally occurring OSPW bacteria for potential future use in an aerobic ex situ OSPW treatment system. Here we evaluate our recovered microbes on their ability to degrade two model NAs, cyclohexane carboxylic acid and cyclohexane acetic acid. Using OSPW as a source for a bacterial inoculum, we were able to compare single and multispecies OSPW cultures, grown as either a biofilm, or as a planktonic suspension. Furthermore, we examined the effect of available nutrients on the ability of these cultures to degrade NAs. All biofilms were grown using the Calgary Biofilm Device. GC-MS, and GC-FID reveal that multispecies biofilm and planktonic cultures are each capable of degrading both NAs; a trait not observed for single species cultures. Moreover, complementary carbon sources have a tangible effect on the ability of the cultures to initiate the degradation of the NAs. PMID:24325800

Demeter, Marc A; Lemire, Joe; George, Iain; Yue, Gordon; Ceri, Howard; Turner, Raymond J

2014-02-01

405

Effect of ozonation on the naphthenic acids' speciation and toxicity of pH-dependent organic extracts of oil sands process-affected water.  

PubMed

The presence of naphthenic acids (NAs) and other organic constituents in oil sands process-affected water (OSPW) stored in tailings ponds, poses a serious environmental threat due to their potential toxicity to aquatic organisms and wild life. In this work, four fractions of OSPW, extracted by dichloromethane at different pHs, were ozonated to determine the ozone impact on NAs degradation. Extracts distributions showed that high carbon number NAs (14-22) were associated with higher pH fractions (pH>7) and smaller carbon number NAs (7-13) with lower pH fractions (pH?7). Extracts showed similar hydrogen deficiency (Z-number) patterns centered on Z=6. Analysis of the speciation of NAs and oxidized NAs in the four fractions showed that ozonation degraded most NAs (55% to 98%). Despite the high degradation levels, there was still significant toxicity of the fractions toward goldfish macrophages and measurable toxicity toward Vibrio fischeri. The toxicity of such a complex matrix as OSPW may be attributed to other organic compounds and degradation by-products not currently detected. Thus, there is a need to elucidate which compounds are responsible for the remaining OSPW toxicity and to determine if combined processes, such as ozonation followed by biological treatment, are able to completely detoxify OSPW. This work is taking the first steps into this direction, narrowing down the range of compounds which might be responsible for the toxicity. PMID:25460940

Klamerth, Nikolaus; Moreira, Jesús; Li, Chao; Singh, Arvinder; McPhedran, Kerry N; Chelme-Ayala, Pamela; Belosevic, Miodrag; Gamal El-Din, Mohamed

2015-02-15

406

The NYC native air sampling pilot project: using HVAC filter data for urban biological incident characterization.  

PubMed

Native air sampling (NAS) is distinguished from dedicated air sampling (DAS) devices (eg, BioWatch) that are deployed to detect aerosol disseminations of biological threat agents. NAS uses filter samples from heating, ventilation, and air conditioning (HVAC) systems in commercial properties for environmental sampling after DAS detection of biological threat agent incidents. It represents an untapped, scientifically sound, efficient, widely distributed, and comparably inexpensive resource for postevent environmental sampling. Calculations predict that postevent NAS would be more efficient than environmental surface sampling by orders of magnitude. HVAC filter samples could be collected from pre-identified surrounding NAS facilities to corroborate the DAS alarm and delineate the path taken by the bioaerosol plume. The New York City (NYC) Native Air Sampling Pilot Project explored whether native air sampling would be acceptable to private sector stakeholders and could be implemented successfully in NYC. Building trade associations facilitated outreach to and discussions with property owners and managers, who expedited contact with building managers of candidate NAS properties that they managed or owned. Nominal NAS building requirements were determined; procedures to identify and evaluate candidate NAS facilities were developed; data collection tools and other resources were designed and used to expedite candidate NAS building selection and evaluation in Manhattan; and exemplar environmental sampling playbooks for emergency responders were completed. In this sample, modern buildings with single or few corporate tenants were the best NAS candidate facilities. The Pilot Project successfully demonstrated that in one urban setting a native air sampling strategy could be implemented with effective public-private collaboration. PMID:21793731

Ackelsberg, Joel; Leykam, Frederic M; Hazi, Yair; Madsen, Larry C; West, Todd H; Faltesek, Anthony; Henderson, Gavin D; Henderson, Christopher L; Leighton, Terrance

2011-09-01

407

PREJUICIO Y DISTANCIA SOCIAL HACIA PERSONAS HOMOSEXUALES POR PARTE DE JÓVENES UNIVERSITARIOS  

PubMed Central

Se realizó un estudio descriptivo transversal con el propósito de explorar actitudes de rechazo y distancia social hacia las personas gays y lesbianas (GL) en 565 universitarios. Se utilizó una escala para medir Prejuicio y otra escala para medir Distancia Social. Los participantes reflejaron niveles moderados de prejuicio y distancia social (DS) hacia las personas gays y lesbianas. Los varones (M=104.5, DT= 27.47) mostraron significativamente más prejuicio que las mujeres (M=98.8, DT= 23.41). Los hombres (M=22.7, DT= 7.00) mostraron significativamente mayor DS que las mujeres (M=21.1, DT= 5.41). Las personas que asisten con regularidad a la iglesia mostraron más prejuicio y DS que los que no asisten. Se analiza importancia de incluir el tema de la diversidad sexual a través del currículo para desmontar prejuicios hacia la comunidad homosexual. PMID:25606066

Fernández Rodríguez, María del C.; Squiabro, José Calderón

2014-01-01

408

Alternative Architectures for Distributed Work in the National Airspace System  

NASA Technical Reports Server (NTRS)

The architecture for the National Airspace System (NAS) in the United States has evolved over time to rely heavily on the distribution of tasks and control authority in order to keep cognitive complexity manageable for any one individual. This paper characterizes a number of different subsystems that have been recently incorporated in the NAS. The goal of this discussion is to begin to identify the critical parameters defining the differences among alternative architectures in terms of the locus of control and in terms of access to relevant data and knowledge. At an abstract level, this analysis can be described as an effort to describe alternative "rules of the game" for the NAS.

Smith, Philip J.; Billings, Charles E.; Chapman, Roger; Obradovich, Heintz; McCoy, C. Elaine; Orasanu, Judith

2000-01-01

409

Clarification.  

PubMed

A News & Comment article by Jon Cohen about an investigation of indirect costs charged by the National Academy of Sciences (NAS) to federal grants and contracts (22 Nov., p. 1103) reported that congressional staff members had inquired about a condominium owned by the Academy at the Watergate building. The article should have noted that NAS officials responded that the apartment, which has served as the residence of the NAS president for 25 years, is not charged to indirect costs but is paid for entirely with private funds. PMID:17782188

1991-12-13

410

Neonatal abstinence syndrome: treatment and pediatric outcomes.  

PubMed

Recent rise in rates of opiate replacement therapy among pregnant women have resulted in increasing number of infants requiring treatment for neonatal abstinence syndrome (NAS). Short-term and long-term developmental outcomes associated with prenatal opiate exposure are discussed, including symptoms and severity of NAS, and early cognitive and motor delays. Maternal and infant risk factors are discussed, and include patterns of maternal substance use during pregnancy, genetic risk, polysubstance exposure pharmacological treatment for NAS and breastfeeding. The importance of characterizing corollary environmental risk factors is also considered. PMID:23314720

Logan, Beth A; Brown, Mark S; Hayes, Marie J

2013-03-01

411

Phase I Clinical Trial of Oral Curcumin: Biomarkers of Systemic Activity and Compliance  

Microsoft Academic Search

Curcumin, a polyphenolic antioxidant derived from a dietary spice, exhibits anticancer activity in rodents and in humans. Its efficacy appears to be related to induction of glutathione S-transferase enzymes, inhibition of prostag- landin E2 (PGE2) production, or suppression of oxidative DNA adduct (M1G) formation. We designed a dose-escala- tion study to explore the pharmacology of curcumin in humans. Fifteen patients

Ricky A. Sharma; Stephanie A. Euden; Sharon L. Platton; Darren N. Cooke; Aisha Shafayat; Heather R. Hewitt; Timothy H. Marczylo; Bruno Morgan; David Hemingway; Simon M. Plummer; Munir Pirmohamed; Andreas J. Gescher; William P. Steward

2004-01-01

412

LA FSICA AL ENCUENTRO DE LA COMPLEJIDAD Miguel A. F. Sanjun  

E-print Network

XX. Por un lado, su Teoría de la Relatividad nos ayudó a entender el mundo a escalas cósmicas y por el Año Mundial de la Física, se celebró durante el mes de Julio la XIII Conferencia General de la. Relatividad, Materia y Cosmología 3. Movimiento Browniano, Sistemas Complejos y Física en Biología Es

Rey Juan Carlos, Universidad

413

Javier @Toret. UOC/iN3 Barcelona DatAnalysis15M Research Network: y X.net. Patrones comunes de los movimientos en red 2011 2013  

E-print Network

el uso estrátegico de las redes sociales y las identidades coletivas en red, + la falta de democracia táctico de la redes sociales y las identidades colectivas, más la toma del espacio urbano condicionan procesos autoorganización social a gran escala ¿Ha utilizado en alguna ocasión sitios de redes sociales

Geffner, Hector

414

LA TEORIA DE LA DISONANCIA: UN ENCUENTRO ENTRE MUSICA Y MATEMATICAS  

E-print Network

LA TEOR´IA DE LA DISONANCIA: UN ENCUENTRO ENTRE M´USICA Y MATEM´ATICAS XAVIER GR`ACIA Dep. Matem´usica y matem´atica Espectros de los instrumentos musicales Teor´ia de las escalas Teor´ia de la) Disonancia, m´usica y matem´aticas 3 / 48 La consonancia Pit´agoras de Samos, siglo VI aC Dos cuerdas

Gràcia, Xavier

415

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.  

Code of Federal Regulations, 2010 CFR

...by Escherichia coli, urinary tract infections caused by Escherichia coli, and wound infections caused by Staphylococcus aureus. 1 1 These conditions are NAS/NRC reviewed and deemed effective. Applications for these uses need...

2010-04-01

416

77 FR 47795 - Disease Associated With Exposure to Certain Herbicide Agents: Peripheral Neuropathy  

Federal Register 2010, 2011, 2012, 2013, 2014

...neuropathies, regardless of whether they are transient or persistent in nature. In 1996, NAS...occurrence of ``acute and subacute transient peripheral neuropathy.'' In subsequent...description of the condition to ``early onset transient peripheral neuropathy.'' This...

2012-08-10

417

Dynamic reconfiguration of terminal airspace during convective weather  

E-print Network

Dynamic airspace configuration (DAC) algorithms strive to restructure the U.S. National Airspace System (NAS) in ways that allow air traffic control to better manage aircraft flows. Although past research has largely focused ...

Michalek, Diana

418

76 FR 13084 - Establishment of Area Navigation (RNAV) Routes; Western United States  

Federal Register 2010, 2011, 2012, 2013, 2014

...IFR) operations within the NAS. Specifically, these routes will improve departure flow from the San Francisco/Oakland, CA, Terminal area by providing additional parallel departure routings and improve arrival flow from Salt Lake ARTCC...

2011-03-10

419

75 FR 76648 - Proposed Establishment of Area Navigation (RNAV) Routes; Western United States  

Federal Register 2010, 2011, 2012, 2013, 2014

...operations within the NAS. Specifically these proposed routes would improve departure flow from the San Francisco/Oakland, CA, Terminal area by providing additional parallel departure routings and improve arrival flow from Salt Lake ARTCC...

2010-12-09

420

Application of the Web-based Interspecies Correlation Estimation (Web-ICE) tool to assess risks of national pesticide registrations to federally listed (threatened and endangered) species  

EPA Science Inventory

The National Academy of Science (NAS) recently recommended exploration of predictive tools, such as interspecies correlation estimation (ICE), to estimate acute toxicity values for listed species and support development of species sensitivity distributions (SSDs). We explored the...

421

Integrated optimization model for airline schedule design : profit maximization and issues of access for small markets  

E-print Network

The purpose of the National Airspace System Strategy Simulator is to provide the FAA with a decision support system to evaluate long-term infrastructure and regulatory strategies. The NAS strategy simulator consists of ...

Garcia, Flora A., 1979-

2004-01-01

422

A Celebration of the Space Shuttle Program - Duration: 1:45.  

NASA Video Gallery

On September 23, 2011, NASA Langley hosted a Shuttle Celebration at the Virginia Air & Space Center in Hampton, Va. More than 650 guests attended, including STS-135 Commander Chris Ferguson and NAS...

423

77 FR 70140 - Emerging Technology and Research Advisory Committee; Notice of Partially Closed Meeting  

Federal Register 2010, 2011, 2012, 2013, 2014

...Provision 5. 3D Bio-printing 6. NAS study on Nanotech Initiative ``tentative'' 7. Rare Earths Study 8. Additive Manufacturing ``tentative'' The open sessions will be accessible via teleconference to 40 participants on a first...

2012-11-23

424

32 CFR 245.6 - Abbreviations and acronyms.  

Code of Federal Regulations, 2010 CFR

...evacuation flight NAS—National Airspace System NEADS—Northeast Air Defense Sector (NORAD) NORAD—North American Aerospace Defense Command PACAF—Pacific Air Forces SCA—Security Control Authorization SEADS—Southeast Air Defense...

2010-07-01

425

Development of Fast-Time Simulation Techniques to Model Safety Issues in the National Airspace System  

E-print Network

safety assessment, including NAS air traffic operations, human performance, and risk assessment models Developed functional specifications for aircraft andAircraft Performance Risk Assessment Model Air Route Traffic Control Center Aviation Safety

2002-01-01

426

Space-X Launches Falcon 9 on Demonstration Flight - Duration: 2:20.  

NASA Video Gallery

SpaceX's Falcon 9 rocket and Dragon spacecraft launched from Launch Complex 40 at Cape Canaveral Air Force Station at 10:43 a.m. EST on Wednesday, Dec. 8. This is first demonstration flight for NAS...

427

75 FR 81270 - Notice of Public Information Collection(s) Being Submitted for Review and Approval to the Office...  

Federal Register 2010, 2011, 2012, 2013, 2014

...compatibility with the National Airspace System (NAS...public safety, national defense, and homeland...Commission's Access to Numbering Resource...adopted interstate access charge and universal...deregulatory national policy...

2010-12-27

428

78 FR 25100 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting  

Federal Register 2010, 2011, 2012, 2013, 2014

...Aeronautics Committee, National Aeronautics and Space...Integration into the National Airspace System (NAS) Phase...before receiving an access badge. Attendees will...Headquarters. Foreign nationals attending this...

2013-04-29

429

77 FR 43275 - Extension of Public Comment Period for the Draft Environmental Impact Statement for Naval Air...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Public Comment Period for the Draft Environmental Impact Statement for Naval Air Station Key West Airfield Operations...Department of the Navy's (DoN) Draft Environmental Impact Statement (EIS) for Naval Air Station (NAS) Key West...

2012-07-24

430

75 FR 57848 - Revocation of Class E Airspace, Brunswick, ME; and Establishment of Class E Airspace, Wiscasset, ME  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. 10-ANE-10] Revocation of Class E Airspace, Brunswick, ME; and Establishment of Class E Airspace, Wiscasset, ME AGENCY: Federal Aviation...SUMMARY: This action removes Class E Airspace at Brunswick NAS, Brunswick,...

2010-09-23

431

Safety Considerations for Operation of Unmanned Aerial Vehicles in the National Airspace System  

E-print Network

There is currently a broad effort underway in the United States and internationally by several organizations to craft regulations enabling the safe operation of UAVs in the NAS. Current federal regulations governing unmanned ...

Weibel, Roland E

2006-11-21

432

Safety considerations for operation of different classes of unmanned aerial vehicles in the National Airspace System  

E-print Network

There is currently a broad effort underway in the United States and internationally by several organizations to craft regulations enabling the safe operation of UAVs in the NAS. Current federal regulations governing unmanned ...

Weibel, Roland E. (Roland Everett)

2005-01-01

433

JWST Secondary Mirror Deploy Timelapse - Duration: 1:26.  

NASA Video Gallery

Setting up NASA's James Webb Space Telescope's secondary mirror in space will require special arms that resemble a tripod that was recently demonstrated in a NASA cleanroom. TRT: 1:25 / Credit: NAS...

434

Benchmarking Parallel Java Master's Project Report  

E-print Network

Benchmarking Parallel Java Master's Project Report Asma'u Sani Mohammed Java API by implementing the OpenMP version of the NAS Parallel Benchmark (NPB in comparison with FORTRAN OpenMP. Benchmarking Parallel Java allows us to understand

Kaminsky, Alan

435

Development of remedial process options: Phase II, Feasibility study: Installation Restoration Program, Naval Air Station Fallon, Fallon, Nevada  

SciTech Connect

This technical memorandum develops process options which are appropriate for environmental restoration activities at Naval Air Station Fallon (NAS Fallon), Nevada. Introduction of contaminants to the environment has resulted from deliberate disposal activities (both through dumping and landfilling) and accidental spills and leaks associated with normal activities at NAS Fallon over its lifetime of operation. Environmental sampling results indicate that the vast majority of contaminants of concern are petroleum hydrocarbon related. These contaminants include JP-4, JP-5, leaded and unleaded gasoline, waste oils and lubricants, hydraulic fluids, and numerous solvents and cleaners. The principal exposure pathways of concern associated with NAS Fallon contaminants appear to be the surface flows and shallow drainage systems to which the base contributes. Available data indicate NAS Fallon IR Program sites are not contributing excessive contamination to surface flows emanating from the base. Contaminants appear to be contained in a relatively immobile state in the shallow subsurface with little or no contaminant migration off site.

Cronk, T.A.; Smuin, D.R. (Oak Ridge National Lab., TN (United States)); Schlosser, R.M. (Oak Ridge Associated Universities, Inc., TN (United States))

1991-11-01

436

A stochastic and dynamic model of delay propagation within an airport network for policy analysis  

E-print Network

As demand for air travel increases over the years and many busy airports operate close to their capacity limits, congestion at some airports on any given day can quickly spread throughout the National Aviation System (NAS). ...

Pyrgiotis, Nikolaos

2012-01-01

437

ALSEP Array E, PSK Transmitter Parts Application Analysis  

E-print Network

-1-71 This ATM document is the Reliability PAA (Parts Application Analysis) of the Teledyne Telemetry Company) was let to Teledyne Telemetry Company (TTC) to fulfill the requirements in the NASA Contract NAS9- 5829

Rathbun, Julie A.

438

ALSEP Array E PSK Transmitter  

E-print Network

FMECA (Failure Mode, Effects and Criticality Analysis) of the Teledyne Telemetry Company's PSK to Teledyne Telemetry Company (TTC) to fulfill the requirements in the NASA Contract NAS 9-5829. An ALSEP

Rathbun, Julie A.

439

ONTOGENY OF PROTEINS FOR USE AS BIOMARKERS OF DEVELOPMENTAL NEUROTOXICITY.  

EPA Science Inventory

The developing nervous system can be uniquely susceptible to adverse effects following exposure to environmental chemicals, and several advisory panels (e.g. ILSI, NRC, NAS) have highlighted the need for rapid and sensitive developmental neurotoxicity testing methods. Measurement...

440

Neonatal abstinence syndrome: essentials for the practitioner.  

PubMed

The incidence of neonatal abstinence syndrome (NAS) has increased dramatically during the past 15 years, likely due to an increase in antepartum maternal opiate use. Optimal care of these patients is still controversial because of the available published literature lacking sufficient sample size, placebo control, and comparative pharmacologic trials. Primary treatment for NAS consists of opioid replacement therapy with either morphine or methadone. Paregoric and tincture of opium have been abandoned because of relative safety concerns. Buprenorphine is emerging as a treatment option with promising initial experience. Adjunctive agents should be considered for infants failing treatment with opioid monotherapy. Traditionally, phenobarbital has been used as adjunctive therapy; however, results of clonidine as adjunctive therapy for NAS appear to be beneficial. Future directions for research in NAS should include validating a simplified scoring tool, conducting comparative studies, exploring home management options, and optimizing management through pharmacogenomics. PMID:25309144

Siu, Anita; Robinson, Christine A

2014-07-01

441

29 Clin Invest Arterioscl 2003;15(2):59-65 59 Fundamento. La hipercolesterolemia familiar  

E-print Network

. Plegamiento de proteínas. Conformación nativa. LDL-RECEPTOR MUTATIONS ALLOWING FAMILIAL HYPERCHOLESTEROLEMIA TO BE CONSIDERED AS A PROTEIN-FOLDING DISEASE Background. Familial hypercholesterolemia (FH) is an autosomic

Sancho, Javier

442

77 FR 42768 - Leadership Meeting on Maternal, Fetal, and Infant Opioid Exposure and Neonatal Abstinence Syndrome  

Federal Register 2010, 2011, 2012, 2013, 2014

...NAS) will bring together leaders in the field of policy, opioid exposed infants, pain treatment during pregnancy, and addiction treatment during and after pregnancy. The meeting will be held on Thursday, August 30th 2012 at the White House...

2012-07-20

443

77 FR 44695 - Revised Meeting Notice: Leadership Meeting on Maternal, Fetal, and Infant Opioid Exposure and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...NAS) will bring together leaders in the field of policy, opioid exposed infants, pain treatment during pregnancy, and addiction treatment during and after pregnancy. The meeting will be held on Thursday, August 30th 2012 in the Indian Treaty...

2012-07-30

444

Saturn and Enceladus Electrical Link - Duration: 0:12.  

NASA Video Gallery

This animated graphic shows how Saturn and its moon Enceladus are electrically linked. Magnetic field lines, invisible to the human eye but detectable by the fields and particles instruments on NAS...

445

Evaluating the depiction of complex RNAV/RNP procedures and analyzing a potential de-cluttering technique  

E-print Network

Performance Based Navigation (PBN) is a key element of the Federal Aviation Administration's (FAA) NextGen Program. In order to increase National Airspace System (NAS) capacity and efficiency, PBN routes and procedures are ...

Butchibabu, Abhizna

2012-01-01

446

Competition and congestion in the National Aviation System : multi-agent, multi-stakeholder approaches for evaluation and mitigation  

E-print Network

The US National Aviation System (NAS) is a complex system with multiple, interacting agents including airlines, passengers, and system operators, each with somewhat different objectives and incentives. These interactions ...

Vaze, Vikrant (Vikrant Suhas)

2011-01-01

447

The Pedogogy of Conciliation in the Bh?gavata Pur?na A \\  

Microsoft Academic Search

Of the eighteen traditionally recognized Pur?nas in Indian religious literature, the Bh?gavata is indisputably the most famous. Scholarly consensus (van Buitenen, T.J. Hopkins, Winternitz, Farquhar, et. al.) regards the text as being a \\

Judith G. Martin

1975-01-01

448

ADVISORY ON UPDATED METHODOLOGY FOR ESTIMATING CANCER RISKS FROM EXPOSURE TO IONIZING RADIATION  

EPA Science Inventory

The National Academy of Sciences (NAS) published the Biological Effects of Ionizing Radiation (BEIR) committee's report (BEIR VII) on risks from ionizing radiation exposures in 2006. The Committee analyzed the most recent epidemiology from the important exposed cohorts and factor...

449

Review and evaluation of national airspace system models  

E-print Network

Abstract from Technical Report Documentation Page: This report is intended to serve as a guide to the availability and capability of state-of-the-art analytical and simulation models of the National Airspace System (NAS). ...

Odoni, Amedeo R.

1979-01-01

450

Revisão sistemática sobre obesidade em adolescentes brasileiros  

Microsoft Academic Search

Resumo - O propósito deste estudo foi revisar, de forma sistemática, a literatura nacional sobre a prevalência e fatores associados à obesidade em adolescentes. A busca foi realizada nas bases de dados Pubmed e Bireme, através dos descritores: \\

Rafael Miranda Tassitano; Maria Cecília Marinho Tenório; Pedro C Hallal

451

Neonatal Abstinence Syndrome: Essentials for the Practitioner  

PubMed Central

The incidence of neonatal abstinence syndrome (NAS) has increased dramatically during the past 15 years, likely due to an increase in antepartum maternal opiate use. Optimal care of these patients is still controversial because of the available published literature lacking sufficient sample size, placebo control, and comparative pharmacologic trials. Primary treatment for NAS consists of opioid replacement therapy with either morphine or methadone. Paregoric and tincture of opium have been abandoned because of relative safety concerns. Buprenorphine is emerging as a treatment option with promising initial experience. Adjunctive agents should be considered for infants failing treatment with opioid monotherapy. Traditionally, phenobarbital has been used as adjunctive therapy; however, results of clonidine as adjunctive therapy for NAS appear to be beneficial. Future directions for research in NAS should include validating a simplified scoring tool, conducting comparative studies, exploring home management options, and optimizing management through pharmacogenomics. PMID:25309144

Robinson, Christine A.

2014-01-01

452

Deep-Sea Research II 49 (2002) 27472768 One-dimensional ecosystem model of the equatorial Pacific  

E-print Network

;1997). Large changes in heat distribution as a result of El Ni*nos and La Ni*nas are communicated through (Philander, 1990). In spite of this accepted importance and the extensive scien- tific data set resulting

Maine, University of

453

4 Science Service Feature . Released on receipt  

E-print Network

#HBL Toward the middle of the seventeenth century a small Swedish colony, ~ O l p nas New Sweden t Beakrifning om Provincien Nya Snrerigel' (IfShort Description of the Province of New Sweden"). There is (or

454

Estudo Comparativo entre os Constituintes Voláteis Liberados por Machos Ceratitis Capitata e Anastrepha obliqua (Diptera: Tephritidae) e seus Frutos Hospedeiros Preferencial Averrhoa carambola L. e Secundário, Carica papaya L.  

E-print Network

??Os machos de moscas-das-frutas (Diptera: Tephritidae) liberam uma mistura complexa de constituintes químicos para atrair machos e fêmeas coespecíficos (feromônio de agregação). Nas espécies de… (more)

Carlos Eduardo da Silva

2005-01-01

455

UNIVERSIDADE FEDERAL DO PARAN -SETOR DE CINCIAS DA SADE SIBI -BIBLIOTECA DE CINCIAS DA SADE -SD  

E-print Network

, teses, capítulos de livros e livros. Alexandre Alessi et al. Avaliação Laboratorial nas energências. 2009 Capítulo de livro Alexandre Alessi Efeitos da Rosiglitazona em coelhos hipercolesterolêmicos

Paraná, Universidade Federal do

456

S a n d i a N a t i o n a l L a b o r a t o r i e s 1 April 2011  

E-print Network

large energy to targets ( 10% efficiency, 10 MJ, 10X other approaches) Large energy may reduce target, Phased R&D, and Roadmap Presented to the NAS Committee on the Prospects for ICF Energy Systems April 1

457

Immunohistochemical markers for the differential diagnosis of nephrogenic adenomas.  

PubMed

Nephrogenic adenoma (NA) is a rare benign lesion commonly occurring in the urinary bladder that poses challenges to devising a diagnosis. In this study, 21 cases of NAs were studied by performing immunohistochemistry for PAX8, p63, CK903, PSA, S100A1, BerEP4, and CEA on routine tissue sections. PAX8 showed diffuse moderate to strong (2+ and 3+) nuclear staining in all of NAs (n = 6 and 15, respectively) and negative in the normal urothelium (n = 15). Nuclear staining for p63 was not seen in any case of NAs examined (n = 19) and was diffuse and strong (3+) in the normal urothelium (n = 14). High-molecular-weight keratin CK903 showed weak (1+) diffuse staining in all of the NAs examined (n = 19) and diffuse and moderate to strong positivity in the normal urothelium (n = 16). PSA staining was negative in both of the NAs (n = 21) and normal urothelium (n = 16). S100A1 showed strong (3+) diffuse staining in 19 of 20 of the NAs examined (n = 19) and diffuse weak (1+) (n = 14) to moderate (n = 3) staining in the normal urothelium. BerEP4 showed focal to diffuse, mild to moderate (1+ and 2+) cytoplasmic staining in all of NAs (n = 2 and 19) and negative in the normal urothelium (n = 19). CEA staining was negative in both of the NAs (n = 21) and normal urothelium (n = 17). A panel composed of PAX8, p63, PSA, S100A1, and CEA appears to be sensitive and specific in differentiating NA from its mimics of urothelial and prostatic origins. PMID:22672805

Quinones, William; Ziober, Amy; Yao, Yuan; Bing, Zhanyong

2013-02-01

458

Estimating the in situ biodegradation of naphthenic acids in oil sands process waters by HPLC/HRMS.  

PubMed

The oil sands industry in Northern Alberta produces large volumes of oil sands process water (OSPW) containing high concentrations of persistent naphthenic acids (NAs; C(n)H(2n+Z)O(2)). Due to the growing volumes of OSPW that need to be reclaimed, it is important to understand the fate of NAs in aquatic systems. A recent laboratory study revealed several potential markers of microbial biodegradation for NAs; thus here we examined for these signatures in field-aged OSPW on the site of Syncrude Canada Ltd. (Fort McMurray, AB). NA concentrations were lower in older OSPW; however parent NA signatures were remarkably similar among all OSPW samples examined, with no discernible enrichment of the highly cyclic fraction as was observed in the laboratory. Comparison of NA signatures in fresh oil sands ore extracts to OSPW in active settling basins, however, suggested that the least cyclic fraction (i.e. Z=0 and Z=-2 homologues) may undergo relatively rapid biodegradation in active settling basins. Further evidence for biodegradation of NAs came from a significantly higher proportion of oxidized NAs (i.e. C(n)H(2n+Z)O(3)+C(n)H(2n+Z)O(4)) in the oldest OSPW from experimental reclamation ponds. Taken together, there is indirect evidence for rapid biodegradation of relatively labile Z=0 and Z=-2 NAs in active settling basins, but the remaining steady-state fraction of NAs in OSPW appear to be very recalcitrant, with half-lives on the order of 12.8-13.6 years. Alternative fate mechanisms to explain the slow disappearance of parent NAs from OSPW are discussed, including adsorption and atmospheric partitioning. PMID:19285705

Han, Xiumei; MacKinnon, Michael D; Martin, Jonathan W

2009-06-01

459

USGS Nonindigenous Aquatic Species database with a focus on the introduced fishes of the lower Tennessee and Cumberland drainages  

USGS Publications Warehouse

The Nonindigenous Aquatic Species (NAS) database (http://nas.er.usgs.gov) functions as a national repository and clearinghouse for occurrence data for introduced species within the United States. Included is locality information on over 1,100 species of vertebrates, invertebrates, and vascular plants introduced as early as 1850. Taxa include foreign (exotic) species and species native to North America that have been transported outside of their natural range. Locality data are obtained from published and unpublished literature, state, federal and local monitoring programs, museum accessions, on-line databases, websites, professional communications and on-line reporting forms. The NAS web site provides immediate access to new occurrence records through a real-time interface with the NAS database. Visitors to the web site are presented with a set of pre-defined queries that generate lists of species according to state or hydrologic basin of interest. Fact sheets, distribution maps, and information on new occurrences are updated as new records and information become available. The NAS database allows resource managers to learn of new introductions reported in their region or nearby regions, improving response time. Conversely, managers are encouraged to report their observations of new occurrences to the NAS database so information can be disseminated to other managers, researchers, and the public. In May 2004, the NAS database incorporated an Alert System to notify registered users of new introductions as part of a national early detection/rapid response system. Users can register to receive alerts based on geographic or taxonomic criteria. The NAS database was used to identify 23 fish species introduced into the lower Tennessee and Cumberland drainages. Most of these are sport fish stocked to support fisheries, but the list also includes accidental and illegal introductions such as Asian Carps, clupeids, various species popular in the aquarium trade, and Atlantic Needlefish (Strongylura marina) that was introduced via the newly-constructed Tennessee-Tombigbee Canal.

Fuller, Pam; Cannister, Matthew

2013-01-01

460

A survey of parallel programming tools  

NASA Technical Reports Server (NTRS)

This survey examines 39 parallel programming tools. Focus is placed on those tool capabilites needed for parallel scientific programming rather than for general computer science. The tools are classified with current and future needs of Numerical Aerodynamic Simulator (NAS) in mind: existing and anticipated NAS supercomputers and workstations; operating systems; programming languages; and applications. They are divided into four categories: suggested acquisitions, tools already brought in; tools worth tracking; and tools eliminated from further consideration at this time.

Cheng, Doreen Y.

1991-01-01

461

Systems integration of Unmanned Aircraft into the National Airspace: Part of the Federal Aviation Administration Next Generation Air Transportation System  

Microsoft Academic Search

The United States Federal Aviation Administration (FAA) Next Generation Air Transportation System (NextGen) is a comprehensive, ongoing transformation of the U.S. National Airspace System (NAS). NextGen will fundamentally change NAS operations by implementing advanced technologies to monitor and operate aircraft. NextGen poses substantial systems integration challenges due to numerous technical, organizational, political, and social perspectives and their complex interdependencies. Specifically,

Ryan N. Van Dyk; Daniel H. Pariseau; Richard E. Dodson; Brendan T. Martin; Alexander T. Radcliffe; Eni A. Austin; Yacov Y. Haimes; Eva Andrijcic; Zhenyu Guo; Jin H. Werner

2012-01-01

462

Carpal Tunnel Syndrome in Female Nurse Anesthetists Versus Operating Room Nurses: Prevalence, Laterality, and Impact of Handedness  

Microsoft Academic Search

Nurse anesthesia may be a high-risk occupation for carpal tunnel syndrome (CTS) in the workplace. We designed a cross-sectional investigation to study the prevalence of CTS in nurse anesthetists (NAs) as compared with operat- ing room nurses (ORNs). Two-hundred forty-four female operating room workers were classified by job title as NAs (n 63) and ORNs (n 181). The case definition

RONALD D. MILLER

463

Diversity of Assimilatory Nitrate Reductase Genes From Plankton and Epiphytes Associated with a Seagrass Bed  

Microsoft Academic Search

Assimilatory nitrate reductase gene fragments were isolated from epiphytes and plankton associated with seagrass blades collected\\u000a from Tampa Bay, Florida, USA. Nitrate reductase genes from diatoms (NR) and heterotrophic bacteria (nasA) were amplified by polymerase chain reaction (PCR) using two sets of degenerate primers. A total of 129 NR and 75 nasA clones from four clone libraries, two from each

Anita Adhitya; Florence I. M. Thomas; Bess B. Ward

2007-01-01

464

Effects of 6-hydroxydopamine lesions of the nucleus accumbens septi and olfactory tubercle on feeding, locomotor activity, and amphetamine anorexia in the rat  

Microsoft Academic Search

In Exp I with 24 male albino Wistar rats, bilateral 6-hydroxydopamine lesions of the nucleus accumbens septi (NAS) and olfactory tubercle (OT) caused enhanced intake of wet mash in 23-hr-food-deprived Ss tested in photocell activity cages during restricted 30-min sessions. This mild hyperphagia was accompanied by a significant hypoactivity in the group with NAS\\/OT lesions. No hyperphagia was observed during

George F. Koob; Susan J. Riley; S. Christine Smith; Trevor W. Robbins

1978-01-01

465

Investigation of Advanced Counterrotation Blade Configuration Concepts for High Speed Turboprop Systems. Task 8: Cooling Flow/heat Transfer Analysis User's Manual  

NASA Technical Reports Server (NTRS)

The focus of this task was to validate the ADPAC code for heat transfer calculations. To accomplish this goal, the ADPAC code was modified to allow for a Cartesian coordinate system capability and to add boundary conditions to handle spanwise periodicity and transpiration boundaries. This user's manual describes how to use the ADPAC code as developed in Task 5, NAS3-25270, including the modifications made to date in Tasks 7 and 8, NAS3-25270.

Hall, Edward J.; Topp, David A.; Heidegger, Nathan J.; Delaney, Robert A.

1994-01-01

466

Development of a Framework to Determine a Mandatory Safety Baseline for Unmanned Aircraft Systems  

Microsoft Academic Search

Unmanned Aircraft Systems (UAS) emerge as a viable, operational technology for potential civil and commercial applications\\u000a in the National Airspace System (NAS). Although this new type of aircraft presents great potential, it also introduces the\\u000a need for a thorough inquiry into its safety impact on the NAS. This study presents a systems-level approach to analyze the\\u000a safety impact of introducing

Ahmet Oztekin; Cynthia Flass; Xiaogong Lee

467

Integrated aviation security for defense-in-depth of next generation air transportation system  

Microsoft Academic Search

To meet the significant increase in civil air traffic demand in the National Airspace System (NAS), the Federal Aviation Administration (FAA) is cooperating with other departments to develop Next Generation Air Transportation System (NextGen). NextGen will greatly increase the NAS capacity, efficiency, safety, flexibility, and environmental protection. Aviation Security is one of the core components in NextGen. Without security protection,

Pan Kamal

2011-01-01

468

Postexposure Prophylactic Effect of Hepatitis B Virus (HBV)-Active Antiretroviral Therapy against HBV Infection.  

PubMed

Retrospective study indicates that hepatitis B virus (HBV)-active nucleoside (nucleotide) analogues (NAs) used for antiretroviral therapy reduce the incidence of acute HBV infections in human immunodeficiency virus (HIV)-infected patients. Learning from HIV postexposure prophylaxis (PEP), we explored the possibility of using NAs in PEP following HBV exposure, if preexposure prophylaxis is feasible clinically. Using freshly isolated primary human hepatocytes cultured in vitro, we analyzed the effect of HBV-active tenofovir and lamivudine in primary HBV infection and also the effect of treatment with these NAs after HBV infection. HBV-active NAs applied from 24 h before inoculation could not prevent the secretion of hepatitis B surface antigen into the culture medium, and cessation of the NAs after inoculation allowed the cells to establish an apparent HBV infection. In contrast, hepatitis B immune globulin was able to prevent HBV infection completely. NA treatment before infection, however, can control the spread of HBV infection, as detected by immunohistochemistry. Practically, starting NA treatment within 2 days of primary HBV infection inhibited viral spread effectively, as well as preexposure treatment. We demonstrated that preexposure NA treatment was not able to prevent the acquisition of HBV infection but prevented viral spread by suppressing the production of mature progeny HBV virions. The effect of postexposure treatment within 2 days was similar to the effect of preexposure treatment, suggesting the possibility of HBV PEP using HBV-active NAs in HIV- and HBV-susceptible high-risk groups. PMID:25512419

Watanabe, Tsunamasa; Hamada-Tsutsumi, Susumu; Yokomaku, Yoshiyuki; Imamura, Junji; Sugiura, Wataru; Tanaka, Yasuhito

2015-02-01

469

Jpcam: a 1.2 Gpixel Camera for the J-Pas Survey  

NASA Astrophysics Data System (ADS)

JPCam is a 14-CCD mosaic camera, using the new e2v 9k-by-9k 10 ?m-pixel 16-channel detectors, to be deployed on a dedicated 2.55 m wide-field telescope at the OAJ (Observatorio Astrofísico de Javalambre) in Aragon, Spain. The camera is designed to perform a Baryon Acoustic Oscillations (BAO) survey of the northern sky. The J-PAS survey strategy will use 54 relatively narrow-band ( 13.8 nm) filters equi-spaced between 370 and 920 nm plus 3 broad-band filters to achieve unprecedented photometric red-shift accuracies for faint galaxies over 8000 square degrees of sky. The cryostat, detector mosaic and read electronics, is being supplied by e2v under contract to J-PAS while the mechanical structure, housing the shutter and filter assembly, is being designed and constructed by a Brazilian consortium led by INPE (Instituto Nacional de Pesquisas Espaciais). The cryostat is bridged to the telescope via a hexapod actuator system to maintain image quality across the field. Four sets of 14 filters are placed in the ambient environment, just above the dewar window but directly in line with the detectors, leading to a mosaic having 10 mm gaps between each CCD. The massive 500 mm aperture shutter is expected to be supplied by the Bonn-Shutter UG. We will present an overview of JPCam, from the filter configuration through to the CCD mosaic camera. A brief outline of the main J-PAS science projects will be included.

Taylor, K.; Marín-Franch, A.; Laporte, R.; Santoro, F. G.; Marrara, L.; Cepa, J.; Cenarro, A. J.; Chueca, S.; Cristobal-Hornillos, D.; Ederoclite, A.; Gruel, N.; Moles, M.; Rueda, F.; Rueda, S.; Varela, J.; Yanes, A.; Benitez, N.; Dupke, R.; Fernández-Soto, A.; Jorden, P.; Lousberg, G.; Molino Benito, A.; Palmer, I.; Mendes de Oliveira, C.; Sodré, L.

470

LISA 8 Science Organizing Committee and Local Organizing Committee LISA 8 Science Organizing Committee and Local Organizing Committee  

NASA Astrophysics Data System (ADS)

Science Organising Committee (SOC) Tom Abel, Stanford University Odylio Aguiar, Instituto Nacional de Pesquisas Espaciais Tal Alexander, Wizemann Institute Peter Bender, University of Colorado Pierre Binetruy, APC - College de France Sasha Buchman, Stanford University Robert Byer, Stanford University Manuela Campanelli, University of Texas Joan Centrella, NASA/Goddard Massimo Cerdonio, University of Padova Eugenio Coccia, University of Roma-2 Neil Cornish, Montana State University Michael Cruise, University of Birmingham Curt Cutler, NASA/JPL Karsten Danzmann, University of Hannover Sam Finn, Penn State University Jens Gundlach, NPL Gerhard Heinzel, Max-Planck-Institut fuer Gravitationsphysik Craig Hogan, University of Washington Jim Hough, University of Glasgow Scott Hughes, MIT Oliver Jennrich, ESTEC Philippe Jetzer, University Zurich Seiji Kawamura, National Observatory, Japan Alberto Lobo, ICE-CSIC and IEEC Avi Loeb, Harvard University Piero Madau, Lick Observatory Yannick Mellier, IAP, Paris Peter Michelson, Stanford University Guido Mueller, University of Florida Sterl Phinney, Caltech Tom Prince, NASA/JPL Doug Richstone, University of Michigan Bernard Schutz, AEI Potsdam Tuck Stebbins, NASA/Goddard Tim Sumner, Imperial College, London Ke-Xun Sun, Stanford University Kip Thorne, Caltech Michele Vallisneri, NASA/JPL Alberto Vecchio, University of Birmingham Jean-Yves Vinet, OCA, Nice Stefano Vitale, University of Trento Rai Weiss, MIT Nick White, NASA/Goddard Local Organising Committee (LOC) Sasha Buchman (Stanford University) Robert Byer (Stanford University) Sara Charbonneau-Lefort (Stanford University) Nancy Christianson (Stanford University) John Conklin (Stanford University) Dan DeBra (Stanford University) Jan Goebel (Stanford University) Vivian Drew (Stanford University) Ke-Xun Sun (Stanford University) Lucy Zhou (Stanford University) Andrea Zoellner (Stanford University)

2011-05-01

471

High Altitude Long Endurance Remotely Operated Aircraft - National Airspace System Integration - Simulation IPT: Detailed Airspace Operations Simulation Plan. Version 1.0  

NASA Technical Reports Server (NTRS)

The primary goal of Access 5 is to allow safe, reliable and routine operations of High Altitude-Long Endurance Remotely Operated Aircraft (HALE ROAs) within the National Airspace System (NAS). Step 1 of Access 5 addresses the policies, procedures, technologies and implementation issues of introducing such operations into the NAS above pressure altitude 40,000 ft (Flight Level 400 or FL400). Routine HALE ROA activity within the NAS represents a potentially significant change to the tasks and concerns of NAS users, service providers and other stakeholders. Due to the complexity of the NAS, and the importance of maintaining current high levels of safety in the NAS, any significant changes must be thoroughly evaluated prior to implementation. The Access 5 community has been tasked with performing this detailed evaluation of routine HALE-ROA activities in the NAS, and providing to key NAS stakeholders a set of recommended policies and procedures to achieve this goal. Extensive simulation, in concert with a directed flight demonstration program are intended to provide the required supporting evidence that these recommendations are based on sound methods and offer a clear roadmap to achieving safe, reliable and routine HALE ROA operations in the NAS. Through coordination with NAS service providers and policy makers, and with significant input from HALE-ROA manufacturers, operators and pilots, this document presents the detailed simulation plan for Step 1 of Access 5. A brief background of the Access 5 project will be presented with focus on Steps 1 and 2, concerning HALE-ROA operations above FL400 and FL180 respectively. An overview of project management structure follows with particular emphasis on the role of the Simulation IPT and its relationships to other project entities. This discussion will include a description of work packages assigned to the Simulation IPT, and present the specific goals to be achieved for each simulation work package, along with the associated deliverables necessary to achieve these goals and the needs of other Access 5 IPTs. The simulation environment chosen for this task is then outlined. This section includes a description of the system architecture, a list of the necessary assumptions made by the Simulation IPT, and the roles, responsibilities and interactions of simulation participants. The method of simulation conduct is presented in the next section with particular emphasis on scenario development and applicability to evaluation of Step 1 HALE-ROA operations. Following, data collection and analysis methods are discussed for air traffic specialists and air vehicle control station operators. Lastly, a schedule of Step 1 simulation activities is presented for reference.

2004-01-01

472

Nitrogen incorporation in group III nitride arsenide materials grown by elemental source molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

Group III-nitride-arsenides are promising materials for long wavelength opto-electronic devices grown on GaAs substrates. The growth of nitride-arsenides was performed in an elemental solid source molecular beam epitaxy system with a plasma cell to supply reactive nitrogen. Growth is carried out with plasma conditions that maximize the amount of atomic nitrogen versus molecular nitrogen, as determined from the emission spectrum of the plasma. The group III growth rate controls the nitrogen concentration in the film. The photoluminescence intensity of GaNAs and GaInNAs quantum wells (QWs) increases drastically and shifts to shorter wavelengths following high temperature anneal. Nitrogen diffusion out of the QWs is responsible for the wavelength shift. We observe a decrease of interstitial nitrogen after anneal. Vertical-cavity surface-emitting lasers with GaInNAs QWs demonstrated a continuous-wave operation. To limit nitrogen diffusion, the GaAs barriers surrounding the GaInNAs QWs were replaced by GaNAs barriers. This new active region resulted in devices emitting at 1.3 ?m.

Spruytte, S. G.; Larson, M. C.; Wampler, W.; Coldren, C. W.; Petersen, H. E.; Harris, J. S.

2001-07-01

473

N-Acetyl-Serotonin Protects HepG2 Cells from Oxidative Stress Injury Induced by Hydrogen Peroxide  

PubMed Central

Oxidative stress plays an important role in the pathogenesis of liver diseases. N-Acetyl-serotonin (NAS) has been reported to protect against oxidative damage, though the mechanisms by which NAS protects hepatocytes from oxidative stress remain unknown. To determine whether pretreatment with NAS could reduce hydrogen peroxide- (H2O2-) induced oxidative stress in HepG2 cells by inhibiting the mitochondrial apoptosis pathway, we investigated the H2O2-induced oxidative damage to HepG2 cells with or without NAS using MTT, Hoechst 33342, rhodamine 123, Terminal dUTP Nick End Labeling Assay (TUNEL), dihydrodichlorofluorescein (H2DCF), Annexin V and propidium iodide (PI) double staining, immunocytochemistry, and western blot. H2O2 produced dramatic injuries in HepG2 cells, represented by classical morphological changes of apoptosis, increased levels of malondialdehyde (MDA) and intracellular reactive oxygen species (ROS), decreased activity of superoxide dismutase (SOD), and increased activities of caspase-9 and caspase-3, release of cytochrome c (Cyt-C) and apoptosis-inducing factor (AIF) from mitochondria, and loss of membrane potential (??m). NAS significantly inhibited H2O2-induced changes, indicating that it protected against H2O2-induced oxidative damage by reducing MDA levels and increasing SOD activity and that it protected the HepG2 cells from apoptosis through regulating the mitochondrial apoptosis pathway, involving inhibition of mitochondrial hyperpolarization, release of mitochondrial apoptogenic factors, and caspase activity. PMID:25013541

Jiang, Jiying; Yu, Shuna; Jiang, Zhengchen; Liang, Cuihong; Yu, Wenbo; Li, Jin; Du, Xiaodong; Wang, Hailiang; Gao, Xianghong; Wang, Xin

2014-01-01

474

Physiological effects and tissue residues from exposure of leopard frogs to commercial naphthenic acids.  

PubMed

Naphthenic acids (NAs) have been cited as one of the main causes of the toxicity related to oil sands process-affected materials and have recently been measured in biological tissues (fish). However, adverse effects have not been a consistent finding in toxicology studies on vertebrates. This study set out to determine two factors: 1) whether exposure to commercial NAs (Refined Merichem) resulted in detectable tissue residues in native amphibians (northern leopard frogs, Lithobates pipiens), and 2) whether such exposure would produce clinical or subclinical toxicity. Frogs were kept in NA solutions (0, 20, or 40 mg/L) under saline conditions comparable to that on reclaimed wetlands in the Athabasca oil sands for 28 days. These exposures resulted in proportional NA concentrations in muscle tissue of the frogs, estimated by gas chromatography-mass spectrometry analyses. Detailed studies determined if the increasing concentrations of NAs, and subsequently increased tissue NA levels, caused a proportional compromise in the health of the experimental animals. Physiological investigations included innate immune function, thyroid hormone levels, and hepatic detoxification enzyme induction, none of which differed in response to increased exposures or tissue concentrations of NAs. Body mass did increase in both the salt- and NA-exposed animals, likely related to osmotic pressure and uptake of water through the skin. Our results demonstrate that commercial NAs are absorbed and deposited in muscle tissue, yet they show few negative physiological or toxicological effects on the frogs. PMID:22903002

Smits, Judit E G; Hersikorn, Blair D; Young, Rozlyn F; Fedorak, Phillip M

2012-10-15

475

Nucleic acid immunization: a prophylactic gene therapy?  

PubMed

Nucleic acid (NA) vaccines may offer the safety of subunit or inactivated vaccines and, at the same time, provide the advantages of live recombinant vaccines, such as induction of a protective cellular immune response. In Germany, the so-called 'Gene Law' regulates the genetic modification of organisms such as prokaryotic or eukaryotic cells for the construction of recombinant NAs intended for use as NA vaccines. Neither NAs nor human beings treated with NAs are subject to Gene Law regulations but preclinical laboratory experiments are regulated by the Gene Law. Gene therapy, as defined in a recent draft of a European guideline for the production of gene therapeutics, includes the genetic modification of human somatic cells via transfer of NAs and thus includes NA vaccines. The guideline provides recommendations for the production of NA vaccines for human use and for preclinical safety testing. NA vaccines are products derived by biotechnological processes, as defined in part A of the annex of Council Regulation (EEC) No. 2309/93 of 22 July 1993. Applications for marketing authorization in Member States of the European Union will thus be reviewed by the European Agency for the Evaluation of Medicinal Products starting from 1 January 1995. Inoculation of NAs encompassing a full-length but int/nef-defective simian immunodeficiency provirus allowing limited replication of viruses released is being investigated at the Paul-Ehrlich-Institute as a model for a NA vaccine against AIDS.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7879417

Cichutek, K

1994-12-01

476

Root-to-shoot long-distance circulation of nicotianamine and nicotianamine-nickel chelates in the metal hyperaccumulator Thlaspi caerulescens.  

PubMed

Plant metal hyperaccumulator species are widely used as models to unravel the heavy metal tolerance and hyperaccumulation mechanisms. Thlaspi caerulescens is capable of tolerating and hyperaccumulating Zn, Cd, and Ni. A search for factors involved in the cellular tolerance to Ni, based on yeast screens, led to isolation of a cDNA encoding a functional nicotianamine (NA) synthase (NAS). The T. caerulescens genome appears to contain a single copy of the NAS gene named TcNAS whose expression is restricted to the leaves. The analysis of dose-response and time-course Ni treatments have revealed that the exposure to Ni triggers the accumulation of NA in the roots. Because neither TcNAS expression nor NAS activity were detected in the roots, the NA accumulation in roots is most probably the result of its translocation from the leaves. Once in the roots, NA, together with Ni, is subsequently found in the xylem, for redirection to the aerial parts. Using liquid chromatography coupled to inductively coupled plasma or electrospray ionization mass spectrometry, it has been shown that part of the Ni is translocated as a stable Ni-NA complex in the xylem sap. This circulation of NA, Ni, and NA-Ni chelates is absent in the non-tolerant non-hyperaccumulator related species T. arvense. Taken together, the results provide direct physiological and chemical evidence for NA and NA-heavy metal complex translocation in a hyperaccumulator species. PMID:17079698

Mari, Stéphane; Gendre, Delphine; Pianelli, Katia; Ouerdane, Laurent; Lobinski, Ryszard; Briat, Jean-François; Lebrun, Michel; Czernic, Pierre

2006-01-01

477

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles. Volume 4, In-vehicle safety  

SciTech Connect

This report is the last of four volumes that identify and assess the environmental, health, and safety issues that may affect the commercial-scale use of sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles. The reports are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD&D) program for Na/S battery technology. The reports review the status of Na/S battery RD&D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers the in-vehicle safety issues of electric vehicles powered by Na/S batteries. The report is based on a review of the literature and on discussions with experts at DOE, national laboratories and agencies, and private industry. It has three major goals: (1) to identify the unique hazards associated with electric vehicle (EV) use; (2) to describe the existing standards, regulations, and guidelines that are or could be applicable to these hazards; and (3) to discuss the adequacy of the existing requirements in addressing the safety concerns of EVs.

Mark, J.

1992-11-01

478

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles  

SciTech Connect

This report is the last of four volumes that identify and assess the environmental, health, and safety issues that may affect the commercial-scale use of sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles. The reports are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD D) program for Na/S battery technology. The reports review the status of Na/S battery RD D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers the in-vehicle safety issues of electric vehicles powered by Na/S batteries. The report is based on a review of the literature and on discussions with experts at DOE, national laboratories and agencies, and private industry. It has three major goals: (1) to identify the unique hazards associated with electric vehicle (EV) use; (2) to describe the existing standards, regulations, and guidelines that are or could be applicable to these hazards; and (3) to discuss the adequacy of the existing requirements in addressing the safety concerns of EVs.

Mark, J

1992-11-01

479

Recombinant Klebsiella oxytoca strains with improved efficiency in removal of high nitrate loads  

SciTech Connect

Klebsiella oxytoca CECT 4460 removes high nitrate loads from industrial wastewaters without accumulation of nitrite under optimal culture conditions; however, under nonoptimal conditions nitrite accumulates. This situation reflects an in vivo-limited functioning of nitrite reductase in this strain. As a way to overcome this limitation, an increase in the nitrite reductase gene dose in K. oxytoca CECT 4460 was considered. To achieve this, the authors cloned and transferred into this strain the Klebsiella pneumoniae nasB gene, which encodes assimilatory nitrite reductase. The delivery vector was either the wide-host-range plasmid pUPE2, in which the nasB gene is expressed from the Escherichia coli P{sub lac} promoter, or a mini-Tn5-Km vector, which upon random insertion in the host chromosome allowed expression of the nasB gene from an unidentified chromosomal host promoter. The effect of the increase in the dose of the nasB gene in K. oxytoca CECT 4460 on the accumulation of nitrite in the culture medium was tested in two recombinant strains. The results obtained showed that K. oxytoca CECT 4460 bearing pUPE2 accumulated 88% less nitrite than the wild-type strain, while the recombinant strain bearing the K. pneumoniae nasB gene in the host chromosome showed a 25% lower level of nitrite accumulation in the culture medium than that of the wild type.

Pinar, G.; Ramos, J.L. [Estacion Experimental del Zaidin--Consejo Superior de Investigaciones Cientificas, Granada (Spain). Dept. of Biochemistry and Molecular and Cellular Biology of Plants

1998-12-01

480

Elevated Nicotianamine Levels in Arabidopsis halleri Roots Play a Key Role in Zinc Hyperaccumulation[W  

PubMed Central

Zn deficiency is among the leading health risk factors in developing countries. Breeding of Zn-enriched crops is expected to be facilitated by molecular dissection of plant Zn hyperaccumulation (i.e., the ability of certain plants to accumulate Zn to levels >100-fold higher than normal plants). The model hyperaccumulators Arabidopsis halleri and Noccaea caerulescens share elevated nicotianamine synthase (NAS) expression relative to nonaccumulators among a core of alterations in metal homeostasis. Suppression of Ah-NAS2 by RNA interference (RNAi) resulted in strongly reduced root nicotianamine (NA) accumulation and a concomitant decrease in root-to-shoot translocation of Zn. Speciation analysis by size-exclusion chromatography coupled to inductively coupled plasma mass spectrometry showed that the dominating Zn ligands in roots were NA and thiols. In NAS2-RNAi plants, a marked increase in Zn-thiol species was observed. Wild-type A. halleri plants cultivated on their native soil showed elemental profiles very similar to those found in field samples. Leaf Zn concentrations in NAS2-RNAi lines, however, did not reach the Zn hyperaccumulation threshold. Leaf Cd accumulation was also significantly reduced. These results demonstrate a role for NAS2 in Zn hyperaccumulation also under near-natural conditions. We propose that NA forms complexes with Zn(II) in root cells and facilitates symplastic passage of Zn(II) toward the xylem. PMID:22374395

Deinlein, Ulrich; Weber, Michael; Schmidt, Holger; Rensch, Stefan; Trampczynska, Aleksandra; Hansen, Thomas H.; Husted, Søren; Schjoerring, Jan K.; Talke, Ina N.; Krämer, Ute; Clemens, Stephan

2012-01-01

481

Conocimientos y autoeficacia asociados a la prevención del VIH y SIDA en mujeres chilenas  

PubMed Central

Resumen Objetivo Evaluar la relación existente entre conocimientos y autoeficacia asociados al VIH/SIDA en mujeres chilenas en desventaja social. Metodología Estudio correlacional, que utiliza la medición basal del estudio “Testeando una intervención en VIH y SIDA en mujeres chilenas”, realizada entre 2006 y 2008, que tiene una muestra de 496 mujeres entre 18 y 49 años residentes en dos comunas de Santiago de Chile. Las participantes respondieron un cuestionario estructurado aplicado por entrevistadoras entrenadas. Este cuestionario incluyó preguntas sobre datos sociodemográficos, escala de conocimientos de conductas de riesgo y autoeficacia, entre otros. Resultados Edad promedio de 32.3±9.1 años, 72.2% vive con su pareja y 42.7% poseen educación media completa. La puntuación media de los conocimientos de la infección por el VIH fue de 8.9±2.5, mientras que para las tres escalas empleadas para medir autoeficacia fueron: “Normas de los pares” =9.8±3.6, “Intención de reducir conductas de riesgo” =12.2±3.6 y “Self Efficacy Form”=20.2±4.7. Los conocimientos tuvieron una correlación positiva débil con la “intención de reducir conductas de riesgo” (r=0.19; p<0.0001) y con la escala “Self Efficacy Form” (r=0.34; p<0.0001), pero no se relacionaron con las “normas de los pares en cuanto a relaciones sexuales seguras” (r=0.13; p=0.78). Conclusión Existe una débil correlación positiva entre el nivel de conocimientos sobre el VIH/SIDA y la autoeficacia en mujeres chilenas en desventaja social. PMID:25284914

Villegas Rodríguez, Natalia; Ferrer Lagunas, Lilian Marcela; Cianelli Acosta, Rosina; Miner, Sarah; Lara Campos, Loreto; Peragallo, Nilda

2014-01-01

482

Optical absorption of dilute nitride alloys using self-consistent Green’s function method  

PubMed Central

We have calculated the optical absorption for InGaNAs and GaNSb using the band anticrossing (BAC) model and a self-consistent Green’s function (SCGF) method. In the BAC model, we include the interaction of isolated and pair N levels with the host matrix conduction and valence bands. In the SCGF approach, we include a full distribution of N states, with non-parabolic conduction and light-hole bands, and parabolic heavy-hole and spin-split-off bands. The comparison with experiments shows that the first model accounts for many features of the absorption spectrum in InGaNAs; including the full distribution of N states improves this agreement. Our calculated absorption spectra for GaNSb alloys predict the band edges correctly but show more features than are seen experimentally. This suggests the presence of more disorder in GaNSb alloys in comparison with InGaNAs. PMID:24475947

2014-01-01

483

A Look at the Impact of High-End Computing Technologies on NASA Missions  

NASA Technical Reports Server (NTRS)

From its bold start nearly 30 years ago and continuing today, the NASA Advanced Supercomputing (NAS) facility at Ames Research Center has enabled remarkable breakthroughs in the space agency s science and engineering missions. Throughout this time, NAS experts have influenced the state-of-the-art in high-performance computing (HPC) and related technologies such as scientific visualization, system benchmarking, batch scheduling, and grid environments. We highlight the pioneering achievements and innovations originating from and made possible by NAS resources and know-how, from early supercomputing environment design and software development, to long-term simulation and analyses critical to design safe Space Shuttle operations and associated spinoff technologies, to the highly successful Kepler Mission s discovery of new planets now capturing the world s imagination.

Biswas, Rupak; Dunbar, Jill; Hardman, John; Bailey, F. Ron; Wheeler, Lorien; Rogers, Stuart

2012-01-01

484

One-pot phase transfer and surface modification of CdSe-ZnS quantum dots using a synthetic functional copolymer.  

PubMed

We present a facile, one-pot procedure for the organic-to-water phase transfer and biofunctionalization of semiconductor nanocrystals (quantum dots, or QDs) which employs a synthetic functional copolymer, namely poly(DMA-NAS-MAPS), consisting of three components: a surface interacting monomer, N,N-dimethylacrylamide (DMA), a chemically reactive monomer, N-acryloyloxysuccinimide (NAS), and a silane monomer, [3-(methacryloyloxy)-propyl]-trimethoxysilane (MAPS). The nanocrystals were transferred to water by exploiting the amphiphilic character of the copolymer backbone. Hydrolyzed MAPS units contributed to improve the solubility of QDs in water, whereas NAS exhibited reactivity toward biomolecules. A solution of streptavidin in phosphate buffer exhibited good dispersion ability leading to a clear and transparent colloidal suspension, indicative of good QD dispersion during phase transfer and purification. Unlike most of the published methods, the proposed functionalization approach does not require coupling agents and multistep reactions. PMID:24225905

Finetti, Chiara; Colombo, Miriam; Prosperi, Davide; Alessio, Giulia; Morasso, Carlo; Sola, Laura; Chiari, Marcella

2014-01-01

485

History of the numerical aerodynamic simulation program  

NASA Technical Reports Server (NTRS)

The Numerical Aerodynamic Simulation (NAS) program has reached a milestone with the completion of the initial operating configuration of the NAS Processing System Network. This achievement is the first major milestone in the continuing effort to provide a state-of-the-art supercomputer facility for the national aerospace community and to serve as a pathfinder for the development and use of future supercomputer systems. The underlying factors that motivated the initiation of the program are first identified and then discussed. These include the emergence and evolution of computational aerodynamics as a powerful new capability in aerodynamics research and development, the computer power required for advances in the discipline, the complementary nature of computation and wind tunnel testing, and the need for the government to play a pathfinding role in the development and use of large-scale scientific computing systems. Finally, the history of the NAS program is traced from its inception in 1975 to the present time.

Peterson, Victor L.; Ballhaus, William F., Jr.

1987-01-01

486

Room-temperature ferromagnetism of diamagnetically-doped ZnO aligned nanorods fabricated by vapor reaction  

NASA Astrophysics Data System (ADS)

Large-scale monocrystalline oxide-diluted magnetic semiconductor (ODMS) Zn1- x Bi x O nanorods arrays (NAs) were prepared within a large doping concentration range from 5% to 20% by a simple chemical vapor deposition. X-ray diffraction and high-resolution transmission electron microscopy reveal the monotonous expansion of the lattice constants with increasing Bi content, due to the effective Bi doping. In particular, room-temperature ferromagnetic (RTFM) behavior with Curie temperature over 363.7 K has been observed based on Bi-doped ZnO nanoarrays, whereas undoped ZnO NAs disappear. The RTFM origin is suggested, in which vacancies can be controlled to tune the FM. The as-formed RTFM NAs would have potential applications in many areas of advanced nanotechnology, such as new spintronic devices and magneto-optic components.

Zhou, ShaoMin; Liu, LiSheng; Lou, ShiYun; Wang, YongQiang; Chen, XiLiang; Yuan, HongLei; Hao, YaoMing; Yuan, RuiJian; Li, Ning

2011-02-01

487

Crystallographic snapshots of iterative substrate translocations during nicotianamine synthesis in archaea  

PubMed Central

Nicotianamine (NA), a small molecule ubiquitous in plants, is an important divalent metal chelator and the main precursor of phytosiderophores. Nicotianamine synthase (NAS) is the enzyme catalyzing NA synthesis by the condensation of three aminopropyl moieties of S-adenosylmethionine (SAM) and the cyclization of one of them to form an azetidine ring. Here we report five crystal structures of an archaeal NAS from Methanothermobacter thermautotrophicus, either free or in complex with its product(s) and substrate(s). These structures reveal a two-domains fold arrangement of MtNAS, a small molecule related to NA (named here thermoNicotianamine or tNA), and an original mechanism of synthesis in a buried reaction chamber. This reaction chamber is open to the solvent through a small inlet, and a single active site allows the selective entrance of only one substrate at a time that is then processed and translocated stepwise. PMID:19805277

Dreyfus, Cyril; Lemaire, David; Mari, Stéphane; Pignol, David; Arnoux, Pascal

2009-01-01

488

Work Package 5: Contingency Management. Mission Planning Requirements Document: Preliminary Version. Revision A  

NASA Technical Reports Server (NTRS)

The purpose of this document is to identify the general flight/mission planning requirements for same-day file-and-fly access to the NAS for both civil and military High-Altitude Long Endurance (HALE) Unmanned Aircraft System (UAS). Currently the scope of this document is limited to Step 1, operations above flight level 43,000 feet (FL430). This document describes the current applicable mission planning requirements and procedures for both manned and unmanned aircraft and addresses HALE UAS flight planning considerations in the future National Airspace System (NAS). It also discusses the unique performance and operational capabilities of HALE UAS associated with the Access 5 Project, presents some of the projected performance characteristics and conceptual missions for future systems, and provides detailed analysis of the recommended mission planning elements for operating HALE UAS in the NAS.

2005-01-01

489

Viral genome structures are optimal for capsid assembly  

E-print Network

Understanding how virus capsids assemble around their nucleic acid (NA) genomes could promote efforts to block viral propagation or to reengineer capsids for gene therapy applications. We develop a coarse-grained model of capsid proteins and NAs with which we investigate assembly dynamics and thermodynamics. In contrast to recent theoretical models, we find that capsids spontaneously `overcharge'; i.e., the negative charge of the NA exceeds the positive charge on capsid. When applied to specific viruses, the optimal NA lengths closely correspond to the natural genome lengths. Calculations based on linear polyelectrolytes rather than base-paired NAs underpredict the optimal length, demonstrating the importance of NA structure to capsid assembly. These results suggest that electrostatics, excluded volume, and NA tertiary structure are sufficient to predict assembly thermodynamics and that the ability of viruses to selectively encapsidate their genomic NAs can be explained, at least in part, on a thermodynamic b...

Perlmutter, Jason D; Hagan, Michael F

2013-01-01

490

Sodium-sulfur Cell Technology Flight Experiment (SSCT)  

NASA Technical Reports Server (NTRS)

The sodium-sulfur battery is emerging as a prime high-temperature energy storage technology for space flight applications. A Na-S cell demonstration is planned for a 1995-96 NASA Space Shuttle flight which focuses on the microgravity effects on individual cells. The experiment is not optimized for battery performance as such. Rather, it maximizes the variety of operating conditions which the Na-S cell is capable of in a relatively short 5-day flight. The demonstration is designed to reveal the effects of microgravity by comparison with ground test control cells experiencing identical test conditions but with gravity. Specifically, limitations of transport dynamics and associated cell performance characteristics should be revealed. The Na-S Cell Technology Flight Experiment consists of three separate experiments designed to determine cell operating characteristics, detailed electrode kinetics and reactant distributions.

Halbach, Carl R.

1992-01-01

491

Knowledge of Rural Nurses' Aides About End-of-Life Care  

PubMed Central

Currently, little is known about the role of nurses' aides (NAs) in rural long-term care facilities or their impact on the process of death and dying in rural healthcare environments. Focus groups with NAs were held in 6 rural counties located in 5 states to assess attitudes and perceptions about end-of-life care and training needs. Key informants from 8 states and the District of Columbia added to the understandings. Nurses' aides (N = 63) and key informans (N = 21) worked in a variety of rural settings that provide end-of-life care (ie, nursing homes, hospitals, hospices, home healthcare agencies). Five themes about the needs of rural NAs around end-of-life care were identified in the focus groups, and 4 themes emerged from key informant interviews. A prototype computer-based training module on communication about end-of-life issues was developed, tested, and found useful and compelling. PMID:16775473

Denham, Sharon A.; Meyer, Michael G.; Rathbun, Ann; Toborg, Mary A.; Thornton, Leslie

2006-01-01

492

OpenSHMEM Performance and Potential: A NPB Experimental Study  

SciTech Connect

OpenSHMEM is a recently introduced open stan- dard for all SHMEM libraries. In this paper we discuss the dif- ferent aspects of porting the NAS parallel benchmarks from their MPI 1 implementations to those that use the new OpenSHMEM library API. We compare performance and scalability of these unoptimized OpenSHMEM NAS benchmarks with their MPI 1, and in some cases, MPI 2 counter parts. Through the perfor- mance results of the OpenSHMEM NAS parallel benchmarks on three different platforms that use different OpenSHMEM library implementations we show that even without optimizations these benchmarks have performance comparable to MPI 1 and better than MPI 2 on more mature library implementations. We also do an in-depth analysis of the performance and expect that with hardware support and better implementation of collectives the OpenSHMEM implementations can outperform MPI.

Pophale, Swaroop [University of Houston, Houston] [University of Houston, Houston; Nanjegowda, Ramachandra [University of Houston, Houston] [University of Houston, Houston; Curtis, Anthony R [ORNL] [ORNL; Chapman, Barbara [University of Houston, Houston] [University of Houston, Houston; Jin, Haoqiang [NASA Ames Research Center] [NASA Ames Research Center; Poole, Stephen W [ORNL] [ORNL; Kuehn, Jeffery A [ORNL] [ORNL

2012-01-01

493

Intelligent Information Fusion in the Aviation Domain: A Semantic-Web based Approach  

NASA Technical Reports Server (NTRS)

Information fusion from multiple sources is a critical requirement for System Wide Information Management in the National Airspace (NAS). NASA and the FAA envision creating an "integrated pool" of information originally coming from different sources, which users, intelligent agents and NAS decision support tools can tap into. In this paper we present the results of our initial investigations into the requirements and prototype development of such an integrated information pool for the NAS. We have attempted to ascertain key requirements for such an integrated pool based on a survey of DSS tools that will benefit from this integrated pool. We then advocate key technologies from computer science research areas such as the semantic web, information integration, and intelligent agents that we believe are well suited to achieving the envisioned system wide information management capabilities.

Ashish, Naveen; Goforth, Andre

2005-01-01

494

DNA-aptamer targeting vimentin for tumor therapy in vivo.  

PubMed

In recent years, new prospects for the use of nucleic acids as anticancer drugs have been discovered. Aptamers for intracellular targets can regulate cellular functions and cause cell death or proliferation. However, intracellular aptamers have limited use for therapeutic applications due to their low bioavailability. In this work, we selected DNA aptamers to cell organelles and nucleus of cancer cells, and showed that an aptamer NAS-24 binds to vimentin and causes apoptosis of mouse ascites adenocarcinoma cells in vitro and in vivo. To deliver the aptamer NAS-24 inside cells, natural polysaccharide arabinogalactan was used as a carrier reagent. The mixture of arabinogalactan and NAS-24 was injected intraperitonealy for 5 days into mice with adenocarcinoma and inhibited adenocarcinoma growth more effectively than free arabinogalactan or the aptamer alone. The use of aptamers to intracellular targets together with arabinogalactan becomes a promising approach for anticancer therapy. PMID:24410722

Zamay, Tatyana N; Kolovskaya, Olga S; Glazyrin, Yury E; Zamay, Galina S; Kuznetsova, Svetlana A; Spivak, Ekaterina A; Wehbe, Mohamed; Savitskaya, Anna G; Zubkova, Olga A; Kadkina, Anastasia; Wang, Xiaoyan; Muharemagic, Darija; Dubynina, Anna; Sheina, Yuliya; Salmina, Alla B; Berezovski, Maxim V; Zamay, Anna S

2014-04-01

495

Neonatal abstinence syndrome: therapeutic interventions.  

PubMed

Neonatal Abstinence Syndrome (NAS) occurs in infants exposed to opiates or illicit drugs during pregnancy. It can be severe and cause long hospital stays after birth and with symptoms up to 6 months after birth. Pharmacologic interventions are commonly used as treatment for NAS; however, their safety and efficacy are not fully recognized. Pharmacologic treatments for NAS include medications such as methadone, buprenorphine, morphine, and phenobarbital. Nonpharmacologic interventions and complementary therapies have been documented in neonates. However, there are gaps in the literature regarding use of these therapies for neonatal withdrawal. This article provides an overview of the possible risks, benefits, and outcomes of pharmacologic and complementary therapies in the neonatal population, and illustrates the gaps in knowledge related to their use for neonatal withdrawal. PMID:23187048

Sublett, Juli

2013-03-01

496

Degradation and aquatic toxicity of naphthenic acids in oil sands process-affected waters using simulated wetlands.  

PubMed

Oil sands process-affected waters (OSPWs) produced during the extraction of bitumen at the Athabasca Oil Sands (AOS) located in northeastern Alberta, Canada, are toxic to many aquatic organisms. Much of this toxicity is related to a group of dissolved organic acids known as naphthenic acids (NAs). Naphthenic acids are a natural component of bitumen and are released into process water during the separation of bitumen from the oil sand ore by a caustic hot water extraction process. Using laboratory microcosms as an analogue of a proposed constructed wetland reclamation strategy for OSPW, we evaluated the effectiveness of these microcosms in degrading NAs and reducing the aquatic toxicity of OSPW over a 52-week test period. Experimental manipulations included two sources of OSPW (one from Syncrude Canada Ltd. and one from Suncor Energy Inc.), two different hydraulic retention times (HRTs; 40 and 400 d), and increased nutrient availability (added nitrate and phosphate). Microcosms with a longer HRT (for both OSPWs) showed higher reductions in total NAs concentrations (64-74% NAs reduction, p<0.05) over the test period, while nutrient enrichment appeared to have little effect. A 96 h static acute rainbow trout (Oncorhynchus mykiss) bioassay showed that the initial acute toxicity of Syncrude OSPW (LC50=67% v/v) was reduced (LC50>100% v/v) independent of HRT. However, EC20s from separate Microtox® bioassays were relatively unchanged when comparing the input and microcosm waters at both HRTs over the 52-week study period (p>0.05), indicating that some sub-lethal toxicity persisted under these experimental conditions. The present study demonstrated that given sufficiently long HRTs, simulated wetland microcosms containing OSPW significantly reduced total NAs concentrations and acute toxicity, but left behind a persistent component of the NAs mixture that appeared to be associated with residual chronic toxicity. PMID:23000048

Toor, Navdeep S; Franz, Eric D; Fedorak, Phillip M; MacKinnon, Michael D; Liber, Karsten

2013-01-01

497

Frequent incidence of escape mutants after successful hepatitis B vaccine response and stopping of nucleos(t)ide analogues in liver transplant recipients.  

PubMed

The combination of nucleos(t)ide analogues (NAs) and hepatitis B immune globulin has been established as safe and effective prophylaxis against hepatitis B virus (HBV) reactivation after liver transplantation (LT). However, the essential weak point of this regimen is its high cost. The hepatitis B (HB) vaccine is an attractive alternative that costs less, and it enables some patients to have sufficiently high hepatitis B surface antibody (HBsAb) titers. Almost no data exist on whether NAs can be stopped safely in such successfully vaccinated patients. We investigated the incidence of HB vaccine escape mutants in liver recipients who had sufficient HBsAb titers after LT and stopped NAs. Among 18 HBV carriers and 7 non-HBV patients who received grafts from hepatitis B core antibody-positive donors, 2 HBV carriers and 6 non-HBV patients who achieved HBsAb titers >100 IU/L for >3 months after posttransplant vaccination were weaned from NAs. For the patients who showed viremia, we analyzed amino acid sequences of the HB envelope protein, and we performed a statistical analysis for the factors associated with viremia. In 4 of the 8 patients who achieved sufficient HBsAb levels after vaccination and stopped NAs, HBV DNA appeared after a median of 12 months. A sequence analysis showed various amino acid mutations, including the a-determinant, in the HB envelope region. Frequent vaccination was shown to be a statistically significant risk factor for inducing viremia. In conclusion, although the HB vaccine is an effective substitute for prophylaxis against HBV reactivation in some patients after LT, frequent vaccination could be a risk factor for producing escape mutants. Our data demonstrate not only that caution must be exercised in stopping NAs in effectively vaccinated patients (especially in patients vaccinated frequently) but also that it is important to set stopping rules for vaccination in transplant patients. PMID:24961506

Ishigami, Masatoshi; Honda, Takashi; Ishizu, Yoji; Onishi, Yasuharu; Kamei, Hideya; Hayashi, Kazuhiko; Ogura, Yasuhiro; Hirooka, Yoshiki; Goto, Hidemi

2014-10-01

498

Hypocretin/orexin preferentially activates caudomedial ventral tegmental area dopamine neurons  

PubMed Central

The hypocretin/orexin (HCRT) neuropeptide system modulates behavioral state and state-dependent processes via actions on multiple neuromodulatory transmitter systems. Recent studies indicate that HCRT selectively increases dopamine (DA) neurotransmission within the prefrontal cortex (PFC) and the shell subregion of the nucleus accumbens (NAs), but not the core subregion of the nucleus accumbens (NAc). The circuitry underlying the differential actions of HCRT across distinct DA systems is unclear. The current study examined whether HCRT preferentially activates PFC- and NAs-projecting relative to NAc-projecting DA neurons within the VTA. One week after infusion of the retrograde tracer fluorogold (FG) into the medial PFC, NAc or NAs, animals received a ventricular infusion of HCRT-1. Subsequent analyses conducted across the rostral-caudal extent of the VTA determined the degree to which: (i) Fos-immunoreactivity (ir) was observed within tyrosine hydroxylase (TH)-ir neurons; (ii) TH-ir was observed within FG-ir neurons; and (iii) Fos-ir was observed within FG-ir neurons. HCRT significantly increased Fos-ir in VTA DA (TH-ir) neurons, primarily in a restricted population of small-to-medium-sized DA neurons located within the caudomedial VTA. Furthermore, within this region of the VTA, PFC- and NAs-projecting TH-ir neurons were more likely to contain Fos-ir than were NAc-projecting TH-ir neurons. These results provide novel evidence that HCRT selectively activates PFC- and NAs-projecting DA neurons within the VTA, and suggest a potential role for HCRT in PFC- and NAs-dependent cognitive and/or affective processes. Moreover, these and other observations suggest that the dysregulation of HCRT–DA interactions could contribute to cognitive/affective dysfunction associated with a variety of behavioral disorders. PMID:18973582

Vittoz, Nicole M.; Schmeichel, Brooke; Berridge, Craig W.

2011-01-01

499

Hypoxylon pulicicidum sp. nov. (Ascomycota, Xylariales), a Pantropical Insecticide-Producing Endophyte  

PubMed Central

Background Nodulisporic acids (NAs) are indole diterpene fungal metabolites exhibiting potent systemic efficacy against blood-feeding arthropods, e.g., bedbugs, fleas and ticks, via binding to arthropod specific glutamate-gated chloride channels. Intensive medicinal chemistry efforts employing a nodulisporic acid A template have led to the development of N-tert-butyl nodulisporamide as a product candidate for a once monthly treatment of fleas and ticks on companion animals. The source of the NAs is a monophyletic lineage of asexual endophytic fungal strains that is widely distributed in the tropics, tentatively identified as a Nodulisporium species and hypothesized to be the asexual state of a Hypoxylon species. Methods and Results Inferences from GenBank sequences indicated that multiple researchers have encountered similar Nodulisporium endophytes in tropical plants and in air samples. Ascomata-derived cultures from a wood-inhabiting fungus, from Martinique and closely resembling Hypoxylon investiens, belonged to the same monophyletic clade as the NAs-producing endophytes. The hypothesis that the Martinique Hypoxylon collections were the sexual state of the NAs-producing endophytes was tested by mass spectrometric analysis of NAs, multi-gene phylogenetic analysis, and phenotypic comparisons of the conidial states. We established that the Martinique Hypoxylon strains produced an ample spectrum of NAs and were conspecific with the pantropical Nodulisporium endophytes, yet were distinct from H. investiens. A new species, H. pulicicidum, is proposed to accommodate this widespread organism. Conclusions and Significance Knowledge of the life cycle of H. pulicicidum will facilitate an understanding of the role of insecticidal compounds produced by the fungus, the significance of its infections in living plants and how it colonizes dead wood. The case of H. pulicicidum exemplifies how life cycle studies can consolidate disparate observations of a fungal organism, whether from environmental sequences, vegetative mycelia or field specimens, resulting in holistic species concepts critical to the assessment of the dimensions of fungal diversity. PMID:23056404

Bills, Gerald F.; González-Menéndez, Victor; Martín, Jesús; Platas, Gonzalo; Fournier, Jacques; Peršoh, Derek; Stadler, Marc

2012-01-01

500

The serotonin-N-acetylserotonin–melatonin pathway as a biomarker for autism spectrum disorders  

PubMed Central

Elevated whole-blood serotonin and decreased plasma melatonin (a circadian synchronizer hormone that derives from serotonin) have been reported independently in patients with autism spectrum disorders (ASDs). Here, we explored, in parallel, serotonin, melatonin and the intermediate N-acetylserotonin (NAS) in a large cohort of patients with ASD and their relatives. We then investigated the clinical correlates of these biochemical parameters. Whole-blood serotonin, platelet NAS and plasma melatonin were assessed in 278 patients with ASD, their 506 first-degree relatives (129 unaffected siblings, 199 mothers and 178 fathers) and 416 sex- and age-matched controls. We confirmed the previously reported hyperserotonemia in ASD (40% (35–46%) of patients), as well as the deficit in melatonin (51% (45–57%)), taking as a threshold the 95th or 5th percentile of the control group, respectively. In addition, this study reveals an increase of NAS (47% (41–54%) of patients) in platelets, pointing to a disruption of the serotonin-NAS–melatonin pathway in ASD. Biochemical impairments were also observed in the first-degree relatives of patients. A score combining impairments of serotonin, NAS and melatonin distinguished between patients and controls with a sensitivity of 80% and a specificity of 85%. In patients the melatonin deficit was only significantly associated with insomnia. Impairments of melatonin synthesis in ASD may be linked with decreased 14-3-3 proteins. Although ASDs are highly heterogeneous, disruption of the serotonin-NAS–melatonin pathway is a very frequent trait in patients and may represent a useful biomarker for a large subgroup of individuals with ASD. PMID:25386956

Pagan, C; Delorme, R; Callebert, J; Goubran-Botros, H; Amsellem, F; Drouot, X; Boudebesse, C; Le Dudal, K; Ngo-Nguyen, N; Laouamri, H; Gillberg, C; Leboyer, M; Bourgeron, T; Launay, J-M

2014-01-01