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1

The Space Science Group  

NSDL National Science Digital Library

The Space Science Group is part of the Division of Mathematics and Sciences at Northwestern State University in Natchitoches, La. The mission of The Space Science Group is to provide activities that encourage participation in math and science, build knowledge of basic concepts, teach basic science skill, and positively influence attitudes. The mission of The Space Science Group is to develop and implement programs which use aspects of the space program to motivate students to study mathematics and science. Many Space Science Group programs are described at the URL below.

1997-01-01

2

International Space Exploration Coordination Group  

E-print Network

for collaborative space exploration missions beginning with the International Space Station (ISS) and continuingInternational Space Exploration Coordination Group The Global Exploration Roadmap August 2013 #12 The Global Exploration Roadmap is being developed by space agencies participating in the International Space

Rathbun, Julie A.

3

Spaces Homotopy Classification Problem Homotopy Groups Homotopy Groups  

E-print Network

Spaces Homotopy Classification Problem Homotopy Groups Homotopy Groups Jie Wu Department of Mathematics National University of Singapore May 25, 2006 #12;Spaces Homotopy Classification Problem Homotopy Groups Homotopy Groups Topological Spaces Homotopy Classification Problem Homotopy Groups #12;Spaces

Wu, Jie

4

POTENTIAL MEMBERS OF STELLAR KINEMATIC GROUPS WITHIN 30 pc OF THE SUN  

SciTech Connect

We analyze the kinematic histories of stars within 30 pc of the Sun, for which three-dimensional spatial coordinates and three-dimensional velocity vectors are available. From this sample, we extract members of stellar kinematic groups (SKGs) in the following manner. First, we consider in the three-dimensional velocity space centered on the local standard of rest, a sphere with a radius of 8 km s{sup -1} centered on the mean velocity vector of a particular SKG. Around each SKG velocity center, we have found a significant excess of stars compared to background field stars. For each candidate, in the three-dimensional spatial coordinate space, its trajectory is traced back in time by the age of the relevant SKG to obtain the estimated distance from the SKG center at the time of the SKG's birth by the epicyclic approximation and harmonic vertical motion. It often happens that a star is a candidate member of multiple SKGs. Then we rank the candidacy to multiple SKGs based on the smallness of distance separations. In this manner, we have kinematically selected 238 candidates. We further impose at least one of the following qualitative criteria for being a member: spectral type A or B, variability, or EUV and X-ray emission. We have finally selected 137 candidate members of SKGs out of a sample of 966 stars.

Nakajima, Tadashi; Morino, Jun-Ichi, E-mail: tadashi.nakajima@nao.ac.jp [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

2012-01-15

5

POTENTIAL MEMBERS OF STELLAR KINEMATICAL GROUPS WITHIN 20 pc OF THE SUN  

SciTech Connect

We analyze the kinematical histories of stars within 20 pc of the Sun, for which three-dimensional spatial coordinates and three-dimensional velocity vectors are available. From this sample, we extract members of stellar kinematical groups (SKGs) in the following manner. First, in the three-dimensional velocity space centered on the local standard of rest, we consider a sphere with a radius of 8 km s{sup -1} centered on the mean velocity vector of a particular SKG. Around each SKG velocity center, we have found a significant excess of stars compared to background stars. For each candidate, in the three-dimensional spatial coordinate space, its trajectory is traced back in time by the age of the relevant SKG, to estimate the distance from the SKG center at the time of the SKG's birth by the epicycle approximation and vertical harmonic motion. It often happens that a star is a candidate member of multiple SKGs. Then we rank the candidacy to multiple SKGs based on the smallness of distance separations. In this manner, we have kinematically selected 74 candidate members of SKGs out of a sample of 383 stars. If we take into account stellar properties, the number is reduced to 68.

Nakajima, Tadashi; Morino, Jun-Ichi [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Fukagawa, Misato, E-mail: tadashi.nakajima@nao.ac.j [Department of Physics, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan)

2010-09-15

6

UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP  

E-print Network

UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP 18th September 2012 STFC 2012 #12;UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP 18th September 2012 STFC · Conclusion #12;UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP 18th September 2012 STFC

7

Interactive 3D Space Group Visualization with CLUCalc and Crystallographic Subperiodic Groups in Geometric Algebra  

NASA Astrophysics Data System (ADS)

The Space Group Visualizer (SGV) for all 230 3D space groups is a standalone PC application based on the visualization software CLUCalc. We first explain the unique geometric algebra structure behind the SGV. In the second part we review the main features of the SGV: The GUI, group and symmetry selection, mouse pointer interactivity, and visualization options. We further introduce the joint use with Hahn (Space-group Symmetry, 5th edn., International Tables of Crystallography, vol. A, Springer, Dordrecht, 2005). In the third part we explain how to represent the 162 so-called subperiodic groups of crystallography in geometric algebra. We construct a new compact geometric algebra group representation symbol, which allows us to read off the complete set of geometric algebra generators. For clarity, we moreover state explicitly which generators are chosen. The group symbols are based on the representation of point groups in geometric algebra by versors.

Hitzer, Eckhard M. S.; Perwass, Christian; Ichikawa, Daisuke

8

UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP  

E-print Network

UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP ESA Lunar Lander ­ L-DEPP C.J. Owen and D.O. Kataria UCL/MSSL #12;UCL DEPARTMENT OF SPACE & CLIMATE PHYSICS SPACE PLASMA PHYSICS GROUP PLASMA PHYSICS GROUP What is L-DEPP? · L-DEPP = Lunar Dust Environment and Plasma Package; · Investigate

Anand, Mahesh

9

Group actions on geodesic Ptolemy spaces  

E-print Network

In this paper we study geodesic Ptolemy metric spaces $X$ which allow proper and cocompact isometric actions of crystallographic or, more generally, virtual polycyclic groups. We show that $X$ is equivariantly rough isometric to a Euclidean space.

Foertsch, Thomas

2008-01-01

10

Point Groups and Space Groups in Geometric Algebra  

Microsoft Academic Search

Abstract. Geometric algebra provides the essential foundation for a new approach to symmetry,groups. Each of the 32 lattice point groups and 230 space groups in three dimensions is generated from a set of three symmetry vectors. This greatly facilitates representation, analysis and application of the groups to molecular modeling and crystal- lography.

David Hestenes

11

Simultaneous observations of Pc 5 pulsations by VHF radars spaced 10 hours in MLT  

NASA Astrophysics Data System (ADS)

Long-period Pc 5 pulsations have been recorded simultaneously by VHF radars operating in Scandinavia and New Zealand. The radars are in opposite hemispheres and are spaced about 10 hours in local time. Those pulsations analyzed are either of the 'quasi-regular' variety or take the form of damped trains that often follow magnetic sudden commencements. An estimation of equatorial plane ion mass densities shows azimuthal variations attributable to several possible causes, including the presence of localized density gradients or a significant proportion of heavy ions. A transient-type pulsation shows the effect of the two radars being directed inside and outside the plasmapause, and a longer lasting event suggests a monochromatic drive of different period on the dawn and dusk flanks of the magnetosphere.

Keys, J. G.

1984-12-01

12

Noncommutative Phase Spaces on Aristotle group  

E-print Network

We realize noncommutative phase spaces as coadjoint orbits of extensions of the Aristotle group in a two-dimensional space. Through these constructions the momenta of the phase spaces do not commute due to the presence of a naturally introduced magnetic field. These cases correspond to the minimal coupling of the momentum with a magnetic potential.

Ancille Ngendakumana; Joachim Nzotungicimpaye; Leonard Todjihounde

2013-07-26

13

Distribution of mica polytypes among space groups.  

NASA Technical Reports Server (NTRS)

All the possible space groups for mica polytypes are deduced by making use of the characteristics of the mica unit layer and stacking mode. The algebraic properties of the vector-stacking symbol of Ross et al. (1966) are examined, and a simple algorithm for deducing the space group from this symbol is presented. A method considered for enumerating all possible stacking sequences of mica polytypes makes use of a computer.

Takeda, H.

1971-01-01

14

Scanning of two-dimensional space groups.  

PubMed

Tables of the scanning of two-dimensional space groups are presented to determine the frieze-group symmetry of lines that transect two-dimensional crystals. It is shown how these tables can be used to predict the (001) projection symmetries of migration-related segments of coincidence site lattice tilt boundaries with [001] tilt axis. PMID:25537394

Litvin, Daniel B

2015-01-01

15

GroupSpace 0.2.0  

NSDL National Science Digital Library

The Internet can serve as a communal gathering place, where like-minded community members can come together to discuss various pressing issues, share documents, take polls, and engage in the decision-making process as well. A recent project, GroupSpace, started at Stanford University as part of a research partnership with a local community organization, allows groups of individuals to do all of the above. As their mission statement suggests, the creation of the program is ??to support the type of deliberation critical to the functioning of smaller, informal organizations in civil society?. It should be noted that this version of GroupSpace is a beta version.

16

The Geroch group in Einstein spaces  

NASA Astrophysics Data System (ADS)

Geroch's solution-generating method is extended to the case of Einstein spaces, which possess a Killing vector and are thus asymptotically (locally) (anti) de Sitter. This includes the reduction to a three-dimensional coset space, the description of the dynamics in terms of a sigma-model and its transformation properties under the SL(2,{R}) group, and the reconstruction of new four-dimensional Einstein spaces. The detailed analysis of the space of solutions is performed using the Hamilton-Jacobi method in the instance where the three-dimensional coset space is conformal to {R} {{S}2}. The cosmological constant appears in this framework as a constant of motion and transforms under SL(2,{R}).

Leigh, Robert G.; Petkou, Anastasios C.; Marios Petropoulos, P.; Tripathy, Prasanta K.

2014-11-01

17

Guide to Space groups There are only 230 ways (space groups) to describe how identical objects can be  

E-print Network

Guide to Space groups There are only 230 ways (space groups) to describe how identical objects can but it gets better than that! If your structure contains a chrial center then any space group that has a mirror or an inversion operation can be rejected. Of the 230 space groups only 74 space groups

Meagher, Mary

18

Optimal space-time constellations from groups  

Microsoft Academic Search

We consider the design of space-time constellations based on group codes for fading channels with multiple transmit and receive antennas. These codes can be viewed as multiantenna extensions of phase-shift keying (PSK), in the sense that all codewords have equal energy, all are rotations of a fixed codeword, and there is a simple differential transmission rule that allows data to

Brian L. Hughes

2003-01-01

19

Schrodinger group on Zhidkov spaces Clement Gallo  

E-print Network

Schr¨odinger group on Zhidkov spaces Cl´ement Gallo UMR de Math´ematiques, Bat. 425 Universit ), and are pertinent to many physical contexts. In nonlinear optics, the so-called dark soliton (see [KLD 2 x 2 + i v 2 (2) The Gross-Pitaevskii equation (see [BeS1], [BeS2] and references therein) iut

Gallo, Clément

20

Actuator grouping optimization on flexible space reflectors  

NASA Astrophysics Data System (ADS)

With the rapid advances in deployable membrane and mesh antenna technologies, the feasibility of developing large, lightweight reflectors has greatly improved. In order to achieve the required accuracy, precision surface control is needed on these lightweight reflectors. While studies have shown that domain control of space reflectors via Polyvinylidene Fluoride (PVDF) actuators is promising, the challenge is to realistically control a large number of distributed actuators with limited number of power supplies. In this research, a new En Mass Elimination method is synthesized to determine the optimal grouping of actuators when the actuator number exceeds the number of power supplies available. An analytical model is developed and the methodology is demonstrated numerically through system simulation on the derived model.

Hill, Jeffrey R.; Wang, K. W.; Fang, Houfei; Quijano, Ubaldo

2011-03-01

21

UCLA IGPP Space Plasma Simulation Group  

NASA Technical Reports Server (NTRS)

During the past 10 years the UCLA IGPP Space Plasma Simulation Group has pursued its theoretical effort to develop a Mission Oriented Theory (MOT) for the International Solar Terrestrial Physics (ISTP) program. This effort has been based on a combination of approaches: analytical theory, large scale kinetic (LSK) calculations, global magnetohydrodynamic (MHD) simulations and self-consistent plasma kinetic (SCK) simulations. These models have been used to formulate a global interpretation of local measurements made by the ISTP spacecraft. The regions of applications of the MOT cover most of the magnetosphere: the solar wind, the low- and high-latitude magnetospheric boundary, the near-Earth and distant magnetotail, and the auroral region. Most recent investigations include: plasma processes in the electron foreshock, response of the magnetospheric cusp, particle entry in the magnetosphere, sources of observed distribution functions in the magnetotail, transport of oxygen ions, self-consistent evolution of the magnetotail, substorm studies, effects of explosive reconnection, and auroral acceleration simulations.

1998-01-01

22

Influence on the resolution based on defective NR-PC double flat lens group with Ag for target detection and imaging  

NASA Astrophysics Data System (ADS)

In this paper, we employed the dynamic scanning scheme to study the influence on target detection and imaging based on the defective NR-PC double flat lens group with Ag by finite-difference-time-domain method. We firstly deduced the focusing imaging circuit diagram of NR-PC flat lens with the Snell extension law and geometrical optics principle. Numerical simulations indicate that significant enhancement of the scattering signal can be obtained while the NR-PC flat lens is used for target detection and imaging. Then the imaging principle of NR-PC flat lens group is studied. We find that the distance between the two lenses can be adjusted flexibly. What is important, the resolution of target detection is greatly improved when incorporating Ag into the NR-PC flat lens group. In conclusion, our investigation makes the target detection and imaging by NR-PC flat lens come true, and optimizes the performance of small target detection and imaging system.

Lu, Jian; Shen, Yang; Shen, TingGen; Lian, YingFei; Wang, FeiFei; Xu, Yang

2014-03-01

23

Universal quantum groups acting on classical and quantum spaces  

E-print Network

Universal quantum groups acting on classical and quantum spaces Lecture 2 - Quantum symmetry groups) Quantum symmetry groups Leeds, 25 May 2010 1 / 24 #12;1 Quantum permutation groups 2 Quantum symmetry groups of finite C-algebras 3 Quantum symmetry groups of AF-algebras 4 Free products of quantum groups

Haase, Markus

24

Space 2: My Body. Space Orientation Group 1.  

ERIC Educational Resources Information Center

Space orientation is a major area of development for preschool and early primary school children. Knowledge about one's own body and about body movements in space is a necessary condition for space orientation. Starting from their own bodies, children learn to focus on the space in which they move. They then learn to take a non-body perspective

van Kuyk, Jef J.

25

The space shuttle payload planning working groups: Executive summaries  

NASA Technical Reports Server (NTRS)

The findings of a space shuttle payload planning group session are presented. The purpose of the workshop is: (1) to provide guidance for the design and development of the space shuttle and the spacelab and (2) to plan a space science and applications program for the 1980 time period. Individual groups were organized to cover the various space sciences, applications, technologies, and life sciences. Summaries of the reports submitted by the working groups are provided.

1973-01-01

26

An IBM PC-based math model for space station solar array simulation  

NASA Technical Reports Server (NTRS)

This report discusses and documents the design, development, and verification of a microcomputer-based solar cell math model for simulating the Space Station's solar array Initial Operational Capability (IOC) reference configuration. The array model is developed utilizing a linear solar cell dc math model requiring only five input parameters: short circuit current, open circuit voltage, maximum power voltage, maximum power current, and orbit inclination. The accuracy of this model is investigated using actual solar array on orbit electrical data derived from the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE), conducted during the STS-41D mission. This simulator provides real-time simulated performance data during the steady state portion of the Space Station orbit (i.e., array fully exposed to sunlight). Eclipse to sunlight transients and shadowing effects are not included in the analysis, but are discussed briefly. Integrating the Solar Array Simulator (SAS) into the Power Management and Distribution (PMAD) subsystem is also discussed.

Emanuel, E. M.

1986-01-01

27

UNIVERSAL QUANTUM GROUPS ACTING ON QUANTUM AND CLASSICAL SPACES  

E-print Network

UNIVERSAL QUANTUM GROUPS ACTING ON QUANTUM AND CLASSICAL SPACES ADAM SKALSKI Abstract. Groups first, be it a finite set, a polygon, a metric space or a manifold. Original definitions of quantum groups (also in the topological context) had rather algebraic character. In these lectures we describe several examples of quantum

Haase, Markus

28

Space station group activities habitability module study  

NASA Technical Reports Server (NTRS)

This study explores and analyzes architectural design approaches for the interior of the Space Station Habitability Module (originally defined as Habitability Module 1 in Space Station Reference Configuration Decription, JSC-19989, August 1984). In the Research Phase, architectural program and habitability design guidelines are specified. In the Schematic Design Phase, a range of alternative concepts is described and illustrated with drawings, scale-model photographs and design analysis evaluations. Recommendations are presented on the internal architectural, configuration of the Space Station Habitability Module for such functions as the wardroom, galley, exercise facility, library and station control work station. The models show full design configurations for on-orbit performance.

Nixon, David

1986-01-01

29

Mixed-Valence, Disordered Structures and Characterization of Iodine-Doped Phthalocyanines: [YbPc(2)]I(2) and [(AsPc)(Pc)]I(2).  

PubMed

Crystals of C(64)H(32)N(16)YbI(2) and C(64)H(32)N(16)AsI(2) were grown directly in the reaction of ytterbium or arsenic powder with 1,2-dicyanobenzene under a stream of iodine at 200 degrees C. Both partially oxidized phthalocyanine complexes crystallize in the P4/mcc space group of the tetragonal system with one molecule per unit cell, with the cell dimensions a = 13.927(2) , c = 6.409(1) , and a = 13.926(2) , c = 6.433(1) for the Yb and As complexes, respectively. The space group of P4/mcc requires that both heavy (iodine and metal) atoms are disordered in these structures. The structures show columnar pseudo-monodimensional stacks of [YbPc(2)] or [(AsPc)(Pc)] units with an average nonintegral charge of +(2)/(3) and linear chains of triiodide I(3)(-) ions, which were detected by Raman spectroscopy. The monodimensional chains of I(3)(-) ions and pseudo-monodimensional aggregates of [YbPc(2)](2/3+) or [(AsPc)(Pc)](2/3+) are aligned along the c-axis of the crystals. The Yb(3+) ion lies in the center, whereas in the [(AsPc)(Pc)] unit the As(3+) ion does not lie in the center between the Pc rings. In the crystal of [(AsPc)(Pc)]I(2) both components in the [(AsPc)(Pc)](2/3+) unit (e.g., AsPc and Pc) with opposite charge are electrostatically interacting. The magnetic susceptibility measurement of the [YbPc(2)]I(2) shows typical Curie-Weiss behavior, and the effective magnetic moment is about 4.60 &mgr;(B). The EPR measurement shows no signal for the Yb complex, while for [(AsPc)(Pc)]I(2) two signals are observed: a sharp narrow line at g = 2.0028 of width approximately 2 G and a broad line at g = 2.0036 of width approximately 9 G. The two EPR signals are associated with two different radical components: a phthalocyaninato (Pc(-)(*)) ring and [AsPc(-)(*)], respectively. Both free radicals are in resonance: [(As(3+)Pc(2)(-))(Pc(-)(*))] <--> [(As(3+)Pc(-)(*))(Pc(2)(-))]. Oxygen effects on the EPR signal of the [(AsPc)(Pc)]I(2) crystal have been detected. The conductivity measured on polycrystalline samples at room temperature equals 2.5-4 x 10(-)(2) and 2.2-3.5 x 10(-)(4) Omega(-)(1) cm(-)(1) for [YbPc(2)]I(2) and [AsPc(Pc)]I(2), respectively. Both complexes exhibit nonmetallic character in conductivity (dsigma/dT > 0). PMID:11670984

Janczak, Jan; Kubiak, Ryszard; Jezierski, Adam

1999-05-01

30

The CPT Group in the de Sitter Space  

E-print Network

$P$-, $T$-, $C$-transformations of the Dirac field in the de Sitter space are studied in the framework of an automorphism set of Clifford algebras. Finite group structure of the discrete transformations is elucidated. It is shown that $CPT$ groups of the Dirac field in Minkowski and de Sitter spaces are isomorphic.

V. V. Varlamov

2005-08-18

31

TRANSLATION NUMBERS OF GROUPS ACTING ON QUASICONVEX SPACES  

E-print Network

TRANSLATION NUMBERS OF GROUPS ACTING ON QUASICONVEX SPACES GREGORY R. CONNER Abstract. We define a group to be translation discrete if it carries a metric in which the translation numbers of the non discontinuously cocompactly on a proper quasiconvex metric space is translation discrete if and only if it does

Conner, Gregory R.

32

The International Space Life Sciences Strategic Planning Working Group  

NASA Technical Reports Server (NTRS)

Throughout the 1980s, ESA and the space agencies of Canada, Germany, France, Japan, and the U.S. have pursued cooperative projects bilaterally and multilaterally to prepare for, and to respond to, opportunities in space life sciences research previously unapproachable in scale and sophistication. To cope effectively with likely future space research opportunities, broad, multilateral, coordinated strategic planning is required. Thus, life scientists from these agencies have allied to form the International Space Life Sciences Strategic Planning Working Group. This Group is formally organized under a charter that specifies the purpose of the Working Group as the development of an international strategic plan for the space life sciences, with periodic revisions as needed to keep the plan current. The plan will be policy-, not operations-oriented. The Working Group also may establish specific implementation teams to coordinate multilateral science policy in specific areas; such teams have been established for space station utilization, and for sharing of flight equipment.

White, Ronald J.; Rabin, Robert; Lujan, Barbara F.

1993-01-01

33

PC index as an indicator of solar wind energy that entered into the magnetosphere: basis for the space weather monitoring  

NASA Astrophysics Data System (ADS)

The PC index has been introduced initially [Troshichev et al., 1988] as a characteristic of the polar cap magnetic activity related to the geoeffective interplanetary electric field EKL which was determined by formula of Kan and Lee [1979]. The recent studies showed that the PC index implication is more significant: the magnetospheric storms and substorms start only if the PC index reaches the definite threshold value (~ 2 mV/m for storms, and >1.5mV/m for substorms); the substorm growth phase duration and substorm intensity are determined by the PC growth rate and substorms are stopped as soon as PC index falls below 1-1.5 mV/m; the storm length is terminated by duration of period, when PC>2mV/m, the storm intensity being linearly related to the PC index averaged for the storm time interval; periodicity of saw-tooth substorms occurring under conditions of steadily high level of geoeffective interplanetary electric field is determined by duration of

Troshichev, O.; Janzhura, A.

2012-04-01

34

Exceptional groups, symmetric spaces and applications  

SciTech Connect

In this article we provide a detailed description of a technique to obtain a simple parameterization for different exceptional Lie groups, such as G{sub 2}, F{sub 4} and E{sub 6}, based on their fibration structure. For the compact case, we construct a realization which is a generalization of the Euler angles for SU(2), while for the non compact version of G{sub 2(2)}/SO(4) we compute the Iwasawa decomposition. This allows us to obtain not only an explicit expression for the Haar measure on the group manifold, but also for the cosets G{sub 2}/SO(4), G{sub 2}/SU(3), F{sub 4}/Spin(9), E{sub 6}/F{sub 4} and G{sub 2(2)}/SO(4) that we used to find the concrete realization of the general element of the group. Moreover, as a by-product, in the simplest case of G{sub 2}/SO(4), we have been able to compute an Einstein metric and the vielbein. The relevance of these results in physics is discussed.

Cerchiai, Bianca L.; Cacciatori, Sergio L.

2009-03-31

35

Isometric group actions on Hilbert spaces: structure of orbits  

E-print Network

Isometric group actions on Hilbert spaces: structure of orbits Yves de Cornulier, Romain Tessera actions, nilpotent groups. 1 Introduction The study of isometric actions of groups on affine Hilbert is a sequel to [CTV], but can be read independently. In [CTV], we focused, given an an isometric action

Tessera, Romain

36

Meeting of intercosmos space physics group  

NASA Astrophysics Data System (ADS)

The 22nd meeting of scientists and specialists of Socialist countries in the Intercosmos program was held in April 1988, in Tbilisi. Taking part in the meeting were well-known Soviet scientists and major foreign specialists from Bulgaria, Hungary, GDR, Cuba, Mongolia, Poland, Rumania, and Czechoslovakia. The meeting focused on a plan for collaboration in space physics for the 1991 to 1995 period and up to the year 2000. The Mars-94 project, which is a component part of the program, Mars-2000, proposed by Soviet scientists, is discussed along with other proposed planetary projects. In the area of high energy astrophysics, a project involving a large orbital observatory (Spektr-Rentgen-Gamma) is being prepared for solving problems associated with cosmology, extragalactic astronomy, and stellar astronomy. It will be carried out through international cooperation with significant developments effected by socialist countries. Two other projects discussed include Radioastron which involves radiointerferometry, and Relikt-2 which will continue research that was begun aboard the unmanned Prognoz-9 station. In the area of solar terrestrial physics, instruments are being designed for the study of X-ray active formations in the solar atmosphere and processes that take place in solar plasma (the Koronas-1, F project, and the Neytron project). The study of cosmic plasma is called for in the Interbol project. Also, the Czech furnace Kristallizator-ChSk-1 is in operation aboard the Mir orbital station and the launch of another unit is expected. All 10 Intercosmos countries are taking part in the preparation of experiments involving space-based materials science.

Frolova, N. A.

1989-06-01

37

Actuator Grouping Optimization on Flexible Space Reflectors  

NASA Technical Reports Server (NTRS)

With the rapid advances in deployable membrane and mesh antenna technologies, the feasibility of developing large, lightweight reflectors has greatly improved. In order to achieve the required surface accuracy, precision surface control is needed on these lightweight reflectors. For this study, an analytical model is shown which combines a flexible Kapton reflector with Polyvinylidene fluoride (PVDF) actuators for surface control. Surface errors are introduced that are similar to real world scenarios, and a least squares control algorithm is developed for surface control. Experimental results on a 2.4 meter reflector show that while the analytical reflector model is generally correct, due to idiosyncrasies in the reflector it cannot be used for online control. A new method called the En Mass Elimination algorithm is used to determine the optimal grouping of actuators when the number of actuators in the system exceeds the number of power supplies available.

Hill, Jeffrey R.; Wang, K. W.; Fang, Houfei; Quijano, Ubaldo

2011-01-01

38

Group theoretical construction of planar noncommutative phase spaces  

SciTech Connect

Noncommutative phase spaces are generated and classified in the framework of centrally extended anisotropic planar kinematical Lie groups as well as in the framework of noncentrally abelian extended planar absolute time Lie groups. Through these constructions the coordinates of the phase spaces do not commute due to the presence of naturally introduced fields giving rise to minimal couplings. By symplectic realizations methods, physical interpretations of generators coming from the obtained structures are given.

Ngendakumana, Ancille, E-mail: nancille@yahoo.fr; Todjihound, Leonard, E-mail: leonardt@imsp.uac.org [Institut de Mathmatiques et des Sciences Physiques (IMSP), Porto-Novo (Benin)] [Institut de Mathmatiques et des Sciences Physiques (IMSP), Porto-Novo (Benin); Nzotungicimpaye, Joachim, E-mail: kimpaye@kie.ac.rw [Kigali Institute of Education (KIE), Kigali (Rwanda)] [Kigali Institute of Education (KIE), Kigali (Rwanda)

2014-01-15

39

Group theoretical construction of planar noncommutative phase spaces  

NASA Astrophysics Data System (ADS)

Noncommutative phase spaces are generated and classified in the framework of centrally extended anisotropic planar kinematical Lie groups as well as in the framework of noncentrally abelian extended planar absolute time Lie groups. Through these constructions the coordinates of the phase spaces do not commute due to the presence of naturally introduced fields giving rise to minimal couplings. By symplectic realizations methods, physical interpretations of generators coming from the obtained structures are given.

Ngendakumana, Ancille; Nzotungicimpaye, Joachim; Todjihound, Leonard

2014-01-01

40

Classifying spaces with virtually cyclic stabilizers for linear groups.  

E-print Network

We show that every discrete subgroup of $\\mathrm{GL}(n,\\mathbb{R})$ admits a finite dimensional classifying space with virtually cyclic stabilizers. Applying our methods to $\\mathrm{SL}(3,\\mathbb{Z})$, we obtain a four dimensional classifying space with virtually cyclic stabilizers and a decomposition of the algebraic $K$-theory of its group ring.

Dieter Degrijse; Ralf Khl; Nansen Petrosyan.

41

SHELXT Integrated space-group and crystal-structure determination  

PubMed Central

The new computer program SHELXT employs a novel dual-space algorithm to solve the phase problem for single-crystal reflection data expanded to the space group P1. Missing data are taken into account and the resolution extended if necessary. All space groups in the specified Laue group are tested to find which are consistent with the P1 phases. After applying the resulting origin shifts and space-group symmetry, the solutions are subject to further dual-space recycling followed by a peak search and summation of the electron density around each peak. Elements are assigned to give the best fit to the integrated peak densities and if necessary additional elements are considered. An isotropic refinement is followed for non-centrosymmetric space groups by the calculation of a Flack parameter and, if appropriate, inversion of the structure. The structure is assembled to maximize its connectivity and centred optimally in the unit cell. SHELXT has already solved many thousand structures with a high success rate, and is optimized for multiprocessor computers. It is, however, unsuitable for severely disordered and twinned structures because it is based on the assumption that the structure consists of atoms. PMID:25537383

Sheldrick, George M.

2015-01-01

42

The space shuttle payload planning working groups. Volume 10: Space technology  

NASA Technical Reports Server (NTRS)

The findings and recommendations of the Space Technology group of the space shuttle payload planning activity are presented. The elements of the space technology program are: (1) long duration exposure facility, (2) advanced technology laboratory, (3) physics and chemistry laboratory, (4) contamination experiments, and (5) laser information/data transmission technology. The space technology mission model is presented in tabular form. The proposed experiments to be conducted by each test facility are described. Recommended approaches for user community interfacing are included.

1973-01-01

43

Bilbao Crystallographic Server. II. Representations of crystallographic point groups and space groups.  

PubMed

The Bilbao Crystallographic Server is a web site with crystallographic programs and databases freely available on-line (http://www.cryst.ehu.es). The server gives access to general information related to crystallographic symmetry groups (generators, general and special positions, maximal subgroups, Brillouin zones etc.). Apart from the simple tools for retrieving the stored data, there are programs for the analysis of group-subgroup relations between space groups (subgroups and supergroups, Wyckoff-position splitting schemes etc.). There are also software packages studying specific problems of solid-state physics, structural chemistry and crystallography. This article reports on the programs treating representations of point and space groups. There are tools for the construction of irreducible representations, for the study of the correlations between representations of group-subgroup pairs of space groups and for the decompositions of Kronecker products of representations. PMID:16489249

Aroyo, Mois I; Kirov, Asen; Capillas, Cesar; Perez-Mato, J M; Wondratschek, Hans

2006-03-01

44

PC6 acupoint stimulation for the prevention of postcardiac surgery nausea and vomiting: a protocol for a two-group, parallel, superiority randomised clinical trial  

PubMed Central

Introduction Postoperative nausea and vomiting (PONV) are frequent but unwanted complications for patients following anaesthesia and cardiac surgery, affecting at least a third of patients, despite pharmacological treatment. The primary aim of the proposed research is to test the efficacy of PC6 acupoint stimulation versus placebo for reducing PONV in cardiac surgery patients. In conjunction with this we aim to develop an understanding of intervention fidelity and factors that support, or impede, the use of PC6 acupoint stimulation, a knowledge translation approach. Methods and analysis 712 postcardiac surgery participants will be recruited to take part in a two-group, parallel, superiority, randomised controlled trial. Participants will be randomised to receive a wrist band on each wrist providing acupressure to PC six using acupoint stimulation or a placebo. Randomisation will be computer generated, use randomly varied block sizes, and be concealed prior to the enrolment of each patient. The wristbands will remain in place for 36?h. PONV will be evaluated by the assessment of both nausea and vomiting, use of rescue antiemetics, quality of recovery and cost. Patient satisfaction with PONV care will be measured and clinical staff interviewed about the clinical use, feasibility, acceptability and challenges of using acupressure wristbands for PONV. Ethics and dissemination Ethics approval will be sought from appropriate Human Research Ethics Committee/s before start of the study. A systematic review of the use of wrist acupressure for PC6 acupoint stimulation reported minor side effects only. Study progress will be reviewed by a Data Safety Monitoring Committee (DSMC) for nausea and vomiting outcomes at n=350. Dissemination of results will include conference presentations at national and international scientific meetings and publications in peer-reviewed journals. Study participants will receive a one-page lay-summary of results. Trial registration number Australian New Zealand Clinical Trials RegistryACTRN12614000589684. PMID:25394818

Cooke, Marie; Rickard, Claire; Rapchuk, Ivan; Shekar, Kiran; Marshall, Andrea P; Comans, Tracy; Doi, Suhail; McDonald, John; Spooner, Amy

2014-01-01

45

1,3,5-Triisopropyl-2-nitrobenzene: Space group correction  

Microsoft Academic Search

The crystal structure of 1,3,5-triisopropyl-2-nitrobenzene, C15H23NO2, has been described and refined in space group Ia [De Ridder, Schenk and Dpp (1993). Acta Cryst. C49, 19701971]. Re-refinement in space group C2\\/c [a = 11.969(2), b = 14.057(2), c = 10.851(2) , = 120.59(1), Dx = 1.054 g cm-3, V = 1571.6(5) 3, Z = 4] was carried out in which

Dirk J. A. De Ridder; Kees Goubitz; Henk Schenk

2000-01-01

46

Radiological Protection in Space: Indication from the ICRP Task Group  

NASA Astrophysics Data System (ADS)

In 2007 the International Commission on Radiological Protection (ICRP) has established a Task Group (Radiation Protection in Space) dealing with the problems of radiation protection of astronauts in space missions. Its first task is a report on "Assessment of Radiation Exposure of Astronauts in Space". When the ICRP published its general recommendations for radiological protection in 2007 (ICRP Publication 103 following ICRP Publication 60 (1991)) it was obvious that these recommendations do not really consider the special situation of astronauts in space. The radiation field with its high content of charged particles of very high energies strongly differs from usual radiation fields on ground. For example, this has consequences for the assessment of doses in the body of astronauts. The ICRP Task Group has discussed this situation and the presentation will deal with some consequences for the concept of radiation dosimetry and radiological protection in space. This includes e. g. the assessment of organ doses and the application of the effective dose concept with its definition of radiation weighting factors. Radiation quality of high energy heavy ions may be defined different than usually performed on ground. An approach of using the quality factor concept in the definition of an "effective dose" is favored for application in space missions similar to the method proposed in NCRP Report 142. New data calculated on the basis of the reference anthropomorphic voxel phantoms recommended by ICRP support this procedure. Individual dosimetry is a further subject of discussion in the Task Group. While the operational dose equivalent quantities generally in use in radiation protection on ground are not helpful for applications in space, different procedures of the assessment of organ and effective doses are applied. The Task Group is dealing with this situation.

Dietze, Gnther

47

Nielsen methods and groups acting on hyperbolic spaces  

Microsoft Academic Search

We show that for any positive integer $n$ there exists a constant $C(n)>0$ such that any $n$-generated group $G$, which acts by isometries on a $\\\\delta$-hyperbolic space (with $\\\\delta>0$), is either free or has a nontrivial element with translation length at most $\\\\delta C(n)$.

Ilya Kapovich; Richard Weidmann

2002-01-01

48

The space shuttle payload planning working groups: Volume 9: Materials processing and space manufacturing  

NASA Technical Reports Server (NTRS)

The findings and recommendations of the Materials Processing and Space Manufacturing group of the space shuttle payload planning activity are presented. The effects of weightlessness on the levitation processes, mixture stability, and control over heat and mass transport in fluids are considered for investigation. The research and development projects include: (1) metallurgical processes, (2) electronic materials, (3) biological applications, and (4)nonmetallic materials and processes. Additional recommendations are provided concerning the allocation of payload space, acceptance of experiments for flight, flight qualification, and private use of the space shuttle.

1973-01-01

49

Gaussian distributions, Jacobi group, and Siegel-Jacobi space  

NASA Astrophysics Data System (ADS)

Let N be the space of Gaussian distribution functions over ?, regarded as a 2-dimensional statistical manifold parameterized by the mean ? and the deviation ?. In this paper, we show that the tangent bundle of N , endowed with its natural Khler structure, is the Siegel-Jacobi space appearing in the context of Number Theory and Jacobi forms. Geometrical aspects of the Siegel-Jacobi space are discussed in detail (completeness, curvature, group of holomorphic isometries, space of Khler functions, and relationship to the Jacobi group), and are related to the quantum formalism in its geometrical form, i.e., based on the Khler structure of the complex projective space. This paper is a continuation of our previous work [M. Molitor, "Remarks on the statistical origin of the geometrical formulation of quantum mechanics," Int. J. Geom. Methods Mod. Phys. 9(3), 1220001, 9 (2012); M. Molitor, "Information geometry and the hydrodynamical formulation of quantum mechanics," e-print arXiv (2012); M. Molitor, "Exponential families, Khler geometry and quantum mechanics," J. Geom. Phys. 70, 54-80 (2013)], where we studied the quantum formalism from a geometric and information-theoretical point of view.

Molitor, Mathieu

2014-12-01

50

Topological classification of crystalline insulators with space group symmetry  

NASA Astrophysics Data System (ADS)

We show that in crystalline insulators, space group symmetry alone gives rise to a topological classification based on the discretization of electric polarization. Using C3 rotational symmetry as an example, we first prove that the polarization is discretized into three distinct classes, i.e., it can only take three inequivalent values. We then prove that these classes are topologically distinct. Therefore, a Z3 topological classification exists, with polarization as a topological class index. A concrete tight-binding model is derived to demonstrate the Z3 topological phase transition. Using first-principles calculations, we identify graphene on a BN substrate as a possible candidate to realize these Z3 topological states. To complete our analysis, we extend the classification of band structures to all 17 two-dimensional space groups. This work will contribute to a complete theory of symmetry-conserved topological phases and also elucidate topological properties of graphenelike systems.

Jadaun, Priyamvada; Xiao, Di; Niu, Qian; Banerjee, Sanjay K.

2013-08-01

51

System theory on group manifolds and coset spaces.  

NASA Technical Reports Server (NTRS)

The purpose of this paper is to study questions regarding controllability, observability, and realization theory for a particular class of systems for which the state space is a differentiable manifold which is simultaneously a group or, more generally, a coset space. We show that it is possible to give rather explicit expressions for the reachable set and the set of indistinguishable states in the case of autonomous systems. We also establish a type of state space isomorphism theorem. Our objective is to reduce all questions about the system to questions about Lie algebras generated from the coefficient matrices entering in the description of the system and in that way arrive at conditions which are easily visualized and tested.

Brockett, R. W.

1972-01-01

52

A Geometric Renormalisation Group in Discrete Quantum Space-Time  

Microsoft Academic Search

We model quantum space-time on the Planck scale as dynamical networks of\\u000aelementary relations or time dependent random graphs, the time dependence being\\u000aan effect of the underlying dynamical network laws. We formulate a kind of\\u000ageometric renormalisation group on these (random) networks leading to a\\u000ahierarchy of increasingly coarse-grained networks of overlapping lumps. We\\u000aprovide arguments that this process

Manfred Requardt; Gottingen Bunsenstrasse

2001-01-01

53

The stratified spaces of a symplectic lie group action  

NASA Astrophysics Data System (ADS)

In this paper we show that the classical symplectic stratification theorem of the reduced spaces of a canonical group action in a symplectic manifold can be obtained even in the absence of a momentum map by replacing this object by its natural generalization, the cylinder valued momentum map introduced by Condevaux, Dazord, and Molino. In the process of proving this result we will provide a normal form for the cylinder valued momentum map.

Ortega, Juan-Pablo; Ratiu, Tudor S.

2006-08-01

54

Space station group activities habitability module study: A synopsis  

NASA Technical Reports Server (NTRS)

Space station habitability was studied by investigating crew activity routines, proximities, ergonomic envelopes, and group volumes. Ten alternative schematic interior designs were proposed. Preliminary conclusions include: (1) in-service interior modifications may be necessary and should be planned for; (2) design complexity will be increased if the module cluster is reduced from five to three; (3) the increased crew circulation attendant upon enhancement of space station activity may produce human traffic bottlenecks and should be planned for; (4) a single- or two-person quiet area may be desirable to provide crew members with needed solitude during waking hours; and (5) the decision to choose a two-shift or three-shift daily cycle will have a significant impact on the design configuration and operational efficiency of the human habitat.

Nixon, David; Glassman, Terry

1987-01-01

55

Report of the Working Group on Space/Lunar Tradeoffs  

NASA Technical Reports Server (NTRS)

The group discussed the advantages and disadvantages of five locations for an optical/infrared array: low-Earth orbit (LEO), Sun-synchronous Earth-orbit, geosynchronous orbit (GEO), Lagrangian points (L4 and L5), and the lunar surface. The factors affecting an array and our assessments of them are given and briefly discussed. In the discussions, two axioms are assumed: (1) Human expansion into space and to the Moon will occur; and (2) The Space Station will be constructed and operational. The major conclusion reached is that baselines of moderate size (greater than 300 m) are best done on the Moon and that large baselines (greater than 10 km) can be done only on the Moon. Three areas needing additional research were identified as follows. (1) Studies are needed on methods to steer long-baseline systems in orbit. This involves learning how to control free-flyers. It is not clear how the difficulty of control varies with orbital elevation. (2) More work is needed on the internal metrology of array systems, both orbital and lunar-surface systems.(3) We need to understand the radiation effects on detectors and electronics and learn how to mitigate them.

1992-01-01

56

The Polycomb group (PcG) protein EZH2 supports the survival of PAX3-FOXO1 alveolar rhabdomyosarcoma by repressing FBXO32 (Atrogin1/MAFbx).  

PubMed

The Polycomb group (PcG) proteins regulate stem cell differentiation via the repression of gene transcription, and their deregulation has been widely implicated in cancer development. The PcG protein Enhancer of Zeste Homolog 2 (EZH2) works as a catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) by methylating lysine 27 on histone H3 (H3K27me3), a hallmark of PRC2-mediated gene repression. In skeletal muscle progenitors, EZH2 prevents an unscheduled differentiation by repressing muscle-specific gene expression and is downregulated during the course of differentiation. In rhabdomyosarcoma (RMS), a pediatric soft-tissue sarcoma thought to arise from myogenic precursors, EZH2 is abnormally expressed and its downregulation in vitro leads to muscle-like differentiation of RMS cells of the embryonal variant. However, the role of EZH2 in the clinically aggressive subgroup of alveolar RMS, characterized by the expression of PAX3-FOXO1 oncoprotein, remains unknown. We show here that EZH2 depletion in these cells leads to programmed cell death. Transcriptional derepression of F-box protein 32 (FBXO32) (Atrogin1/MAFbx), a gene associated with muscle homeostasis, was evidenced in PAX3-FOXO1 RMS cells silenced for EZH2. This phenomenon was associated with reduced EZH2 occupancy and H3K27me3 levels at the FBXO32 promoter. Simultaneous knockdown of FBXO32 and EZH2 in PAX3-FOXO1 RMS cells impaired the pro-apoptotic response, whereas the overexpression of FBXO32 facilitated programmed cell death in EZH2-depleted cells. Pharmacological inhibition of EZH2 by either 3-Deazaneplanocin A or a catalytic EZH2 inhibitor mirrored the phenotypic and molecular effects of EZH2 knockdown in vitro and prevented tumor growth in vivo. Collectively, these results indicate that EZH2 is a key factor in the proliferation and survival of PAX3-FOXO1 alveolar RMS cells working, at least in part, by repressing FBXO32. They also suggest that the reducing activity of EZH2 could represent a novel adjuvant strategy to eradicate high-risk PAX3-FOXO1 alveolar RMS. PMID:24213577

Ciarapica, R; De Salvo, M; Carcarino, E; Bracaglia, G; Adesso, L; Leoncini, P P; Dall'Agnese, A; Walters, Z S; Verginelli, F; De Sio, L; Boldrini, R; Inserra, A; Bisogno, G; Rosolen, A; Alaggio, R; Ferrari, A; Collini, P; Locatelli, M; Stifani, S; Screpanti, I; Rutella, S; Yu, Q; Marquez, V E; Shipley, J; Valente, S; Mai, A; Miele, L; Puri, P L; Locatelli, F; Palacios, D; Rota, R

2014-08-01

57

Quantum Circuit Synthesis using Group Decomposition and Hilbert Spaces  

NASA Astrophysics Data System (ADS)

The exponential nature of Moore's law has inadvertently created huge data storage complexes that are scattered around the world. Data elements are continuously being searched, processed, erased, combined and transferred to other storage units without much regard to power consumption. The need for faster searches and power efficient data processing is becoming a fundamental requirement. Quantum computing may offer an elegant solution to speed and power through the utilization of the natural laws of quantum mechanics. Therefore, minimal cost quantum circuit implementation methodologies are greatly desired. This thesis explores the decomposition of group functions and the Walsh spectrum for implementing quantum canonical cascades with minimal cost. Three different methodologies, using group decomposition, are presented and generalized to take advantage of different quantum computing hardware, such as ion traps and quantum dots. Quantum square root of swap gates and fixed angle rotation gates comprise the first two methodologies. The third and final methodology provides further quantum cost reduction by more efficiently utilizing Hilbert spaces through variable angle rotation gates. The thesis then extends the methodology to realize a robust quantum circuit synthesis tool for single and multi-output quantum logic functions.

Saraivanov, Michael S.

58

The space shuttle payload planning working groups. Volume 1: Astronomy  

NASA Technical Reports Server (NTRS)

The space astronomy missions to be accomplished by the space shuttle are discussed. The principal instrument is the Large Space Telescope optimized for the ultraviolet and visible regions of the spectrum, but usable also in the infrared. Two infrared telescopes are also proposed and their characteristics are described. Other instruments considered for the astronomical observations are: (1) a very wide angle ultraviolet camera, (2) a grazing incidence telescope, (3) Explorer-class free flyers to measure the cosmic microwave background, and (4) rocket-class instruments which can fly frequently on a variety of missions. The stability requirements of the space shuttle for accomplishing the astronomy mission are defined.

1973-01-01

59

Moving a Media Space into the Real World through Group-Robot Interaction  

E-print Network

-robot interaction. 1. INTRODUCTION Unplanned casual interaction is critical to how small groups work together [5Moving a Media Space into the Real World through Group- Robot Interaction Jim Young, Gregor Mc}@cpsc.ucalgary.ca ABSTRACT New generation media spaces let group members see each other and share information. However

Greenberg, Saul

60

Groups quasi-isometric to symmetric spaces Bruce Kleiner and Bernhard Leebz  

E-print Network

Groups quasi-isometric to symmetric spaces Bruce Kleiner and Bernhard Leebz November 10, 1998 Abstract We determine the structure of nitelygenerated groups whichare quasi-isometric to symmetric spaces with no Euclidean de Rham fac- tor, and is a nitely generated group quasi-isometric to the product Ek X

Kleiner, Bruce

61

Modelling LLE and VLE of methanol + n-alkane series using GC-PC-SAFT with a group contribution k ij  

Microsoft Academic Search

The fluid phase diagrams (LLE and VLE) of methanol+n-alkane mixtures series (from C4 up to C16) were modelled using GC-PC-SAFT EOS (Tamouza et al., Fluid Phase Equilibria 222223 (2004) 6776) combined with a recent method for computing kij based on the London theory (NguyenHuynh et al., Industrial & Engineering Chemistry Research 47 (2008) 88478858). This latter method requires pure compound

M. Mourah; D. NguyenHuynh; J. P. Passarello; J. C. de Hemptinne; P. Tobaly

2010-01-01

62

The group approach to AdS space propagators  

E-print Network

We show that AdS two-point functions can be obtained by connecting two points in the interior of AdS space with one point on its boundary by a dual pair of Dobrev's boundary-to-bulk intertwiners and integrating over the boundary point.

Thorsten Leonhardt; Ruben Manvelyan; Werner Ruehl

2003-05-27

63

The group approach to AdS space propagators  

Microsoft Academic Search

We show that AdS two-point functions can be obtained by connecting two points in the interior of AdS space with one point on its boundary by a dual pair of Dobrev's boundary-to-bulk intertwiners and integrating over the boundary point.

Thorsten Leonhardt; Ruben Manvelyan; Werner Rhl

2003-01-01

64

Invariant-theoretic method for calculating Clebsch-Gordan coefficients for space groups  

SciTech Connect

A new invariant-theoretic method to directly calculate Clebsch-Gordan coefficients for space and point groups representations is proposed. The method is exemplified with the space groups O{sub h}{sup 5} and D{sub 6h}{sup 1}. 34 refs.

Aizenberg, A.Ya.; Gufan, Yu.M. [North Caucasus Research Center, Rostov-na-Donu (Russian Federation)

1995-03-01

65

Supporting Group Information Manipulation in Real Public Space by Functional Web and Web Boards  

Microsoft Academic Search

The opportunities to manipulate Web contents by group of people have been increasing, such as group meetings (brain stroming and presentation) and information presentations in real-world public spaces (advertize- ments and guidance etc.). In order to support such information manipulation and communication among people in real-world public space, we introduce the notions of the \\

Tomoyuki UCHIYAMA; Hiroya TANAKA; Katsumi TANAKA

2004-01-01

66

Metricization of thermodynamic-state space and the renormalization group  

Microsoft Academic Search

We suggest a new geometrical interpretation of the renormalization-group transformation near the critical point. Using the Weinhold-Ruppeiner metricization, conformal Killing symmetry is assumed and scaling laws are verified.

L. Disi; G. Forgcs; B. Lukcs; H. L. Frisch

1984-01-01

67

Group Momentum Space and Hopf Algebra Symmetries of Point Particles Coupled to 2+1 Gravity  

NASA Astrophysics Data System (ADS)

We present an in-depth investigation of the SL(2,R) momentum space describing point particles coupled to Einstein gravity in three space-time dimensions. We introduce different sets of coordinates on the group manifold and discuss their properties under Lorentz transformations. In particular we show how a certain set of coordinates exhibits an upper bound on the energy under deformed Lorentz boosts which saturate at the Planck energy. We discuss how this deformed symmetry framework is generally described by a quantum deformation of the Poincar group: the quantum double of SL(2,R). We then illustrate how the space of functions on the group manifold momentum space has a dual representation on a non-commutative space of coordinates via a (quantum) group Fourier transform. In this context we explore the connection between Weyl maps and different notions of (quantum) group Fourier transform appeared in the literature in the past years and establish relations between them.

Arzano, Michele; Latini, Danilo; Lotito, Matteo

2014-07-01

68

Group calls for space policies to transcend politics  

NASA Astrophysics Data System (ADS)

At a 22 May briefing, the American Institute of Aeronautics and Astronautics (AIAA) called on Congress to establish space exploration policy goals which transcend partisan political differences. AIAA president and former NASA administrator Michael Griffin said the goal of establishing human capability to b e a space-faring species is not a short-term goal, nor is it a goal that belongs to only one political party. We will not reach long-term goals without a stable, coherent, sensible plan that transcends elections and leaders, said Griffin, who has provided advice to Republican U.S. presidential candidate Mitt Romney. Griffin pointed to NASA's 2008 authorization as providing the kind of vision needed for NASA. The act called for human return to the Moon and preparation for the capability for permanent bases on the Moon, among other things, he said. That's the kind of thing that we need. All of the goals espoused by the 2008 act were long-term, generational, strategic in scope, Griffin said, adding that the act, which had bipartisan support, demonstrated the kind of societal support, rather than political support, that I believe our space program deserves.

Showstack, Randy

2012-06-01

69

The space shuttle payload planning working groups. Volume 6: Communications and navigation  

NASA Technical Reports Server (NTRS)

The findings of the Communications and Navigation working group of the space shuttle payload planning activity are presented. The basic goals to be accomplished are to increase the use of space systems and to develop new space capabilities for providing communication and navigation services to the user community in the 1980 time period. Specific experiments to be conducted for improving space communication and navigation capabilities are defined. The characteristics of the experimental equipment required to accomplish the mission are discussed.

1973-01-01

70

Marathons versus Spaced Groups: Skin Conductance and the Effects of Time Distribution on Encounter Group Learning.  

ERIC Educational Resources Information Center

Randomly assigned 41 students to 2 twice-weekly groups, which met for 3 hours eight times; 2 marathons, which met continuously for 24 hours; and nontreatment control group. Treatment groups had significant positive changes on 14 of 15 measured personality variables between pre- and post-test, and positive change on all dependent measures between

Loomis, Thomas P.

1988-01-01

71

Fixed point spaces in actions of classical algebraic groups  

Microsoft Academic Search

Let G be a simple classical algebraic group over an algebraically closed field K of characteristic pd 0, and let H be a maximal closed non-subspace subgroup of G. Given such a pair G; H, we obtain a close to best possible upper bound for the ratio dimx G V H=dim x G, where x A G is a semisimple

Timothy C. Burness

2004-01-01

72

Kondo Lattice: Real-Space Renormalization-Group Approach  

Microsoft Academic Search

A one-dimensional analog of the Kondo lattice is studied by a renormalization-group technique. Previous mean-field results are shown to be reasonable: The system under-goes a second-order crossover transition from an antiferromagnetic state to a Kondo-like state at zero temperature as the spin-conduction-electron coupling is increased. Estimates are given for critical exponents and the behavior of correlation functions near the transition.

R. Jullien; J. Fields; S. Doniach

1977-01-01

73

Quantum group symmetric Bargmann-Fock space: Integral kernels, Green functions, driving forces  

Microsoft Academic Search

Raising and lowering operators that transform under the SUq(n)-quantum group get deformed commutation relations. They are represented as adjoint operators on a Hilbert space of noncommutative holomorphic functions. Through the algebraically defined integral on this function space, every operator on the Fock space can also be represented as an integral kernel. The Green function for free harmonic oscillators and spin-1\\/2s

Achim Kempf

1993-01-01

74

Outreach of Astronomy with emphasis to the Solar System by the Space group in Greece  

Microsoft Academic Search

We have a long tradition in Space and Solar System outreach at the University of Athens (Space Group). We have contributed with many popular science articles in encyclopaedias (a total of some 200000 words), magazines and newspapers, public lectures around Greece and radio and TV programmes. We contribute in exhibitions for the public on many occasions (e.g. The British Exploration

X. Moussas; K. Dialynas; G. Babasides; G. Fasoulopoulos; V. Dimitropoulou; D. Prassopoulos; S. Kouphos; E. Spandagos; J. Strikis

2006-01-01

75

Root filtration spaces from Lie algebras and abstract root groups 1  

E-print Network

Root filtration spaces from Lie algebras and abstract root groups 1 Arjeh M. Cohen a, G Academy of Sciences, Kende u. 13-17, 1111 Budapest, Hungary Abstract Both Timmesfeld's abstract root subgroups and simple Lie algebras generated by extremal elements lead to root filtration spaces

Cohen, Arjeh M.

76

Unitary Space-Time Constellations Based on Finite Reflection Group Codes  

E-print Network

1 Unitary Space-Time Constellations Based on Finite Reflection Group Codes Terasan Niyomsataya, Ali diversity unitary space-time constellations for two transmitter antennas. Our proposed constellations unitary constellation designs in the literature. I. INTRODUCTION Consider a multiple-antenna system with M

Nevins, Monica

77

Weak and strong continuity of representations of topologically pseudocomplete groups in locally convex spaces  

NASA Astrophysics Data System (ADS)

Weak and strong continuity conditions for representations of topological groups in locally convex spaces are considered. In particular, weak continuity conditions of reducible locally equicontinuous representations of a topological group in a locally convex space that define weakly continuous representations in an invariant subspace and in the quotient space by this invariant subspace are investigated. These conditions help one to prove the weak continuity of averages and approximations related to weakly continuous locally equicontinuous quasirepresentations of amenable topological groups. Strong continuity conditions for a representation approximating a quasirepresentation of this kind are related to conditions of automatic strong continuity of weakly continuous representations, and fail to hold for some groups, spaces, and representations. In this connection, strong continuity conditions for weakly continuous representations in quasicomplete barrelled locally convex spaces are indicated for a broad class of topologically pseudocomplete groups (which includes the ?ech complete groups and the locally pseudocompact groups). Several examples are discussed, in particular, ones relating to the construction of \\Sigma-products with distinguished subgroups.

Shtern, A. I.

2006-04-01

78

Isometric group of $(?,?)$-type Finsler space and the symmetry of Very Special Relativity  

E-print Network

The Killing equation for a general Finsler space is set up. It is showed that the Killing equation of $(\\alpha,\\beta)$ space can be divided into two parts. One is the same with Killing equation of a Riemannian metric, another equation can be regarded as a constraint. The solutions of Killing equations present explicitly the isometric symmetry of Finsler space. We find that the isometric group of a special case of $(\\alpha,\\beta)$ space is the same with the symmetry of Very Special Relativity (VSR). The Killing vectors of Finsler-Funk space are given. Unlike Riemannian constant curvature space, the 4 dimensional Funk space with constant curvature just have 6 independent Killing vectors.

Xin Li; Zhe Chang; Xiaohuan Mo

2010-01-15

79

OPERATOR K-THEORY FOR GROUPS WHICH ACT PROPERLY AND ISOMETRICALLY ON HILBERT SPACE  

Microsoft Academic Search

Let G be a countable discrete group which acts isometrically and metrically properly on an innite-dimensional Euclidean space. We calculate the K-theory groups of the C-algebras C max(G )a nd Cred(G). Our result is in accordance with the Baum-Connes conjecture.

NIGEL HIGSON; GENNADI KASPAROV

1997-01-01

80

Isometric group actions on Banach spaces and representations vanishing at infinity  

E-print Network

Isometric group actions on Banach spaces and representations vanishing at infinity Yves de group G = Sp(n, 1) acts properly isometrically on Lp(G) if p > 4n + 2. To prove this, we introduce isometric action of G on V , such that the linear part is a C0-representation of G, either has a fixed point

Tessera, Romain

81

Alternative Decompositions of the Regular Representations of Crystallographic Space Groups Into Band Representations  

NASA Astrophysics Data System (ADS)

We discuss the decomposition of the regular representation of crystallographic space groups into elementary band representations. This decomposition is in general not unique. These decompositions can be divided in two groups. On the one hand there are so-called generic ones, which exist for any space groups, involving only band representations corresponding to one Wyckoff position. On the other hand additional decompositions may exist under certain circumstances. Various kinds of these so-called alternative decompositions are discussed in terms of typical examples and some general conditions for their existence are presented.

Zeiner, P.; Dirl, R.; Davies, B. L.

2001-04-01

82

PowerPC News  

NSDL National Science Digital Library

PowerPC News: Full text of an independent electronic magazine published every two weeks for users and developers who want the latest news about the IBM/Motorola/Apple microprocessor family and the systems.

83

PC-SPES (PDQ)  

Cancer.gov

Expert-reviewed information summary about the use of PC-SPES as a treatment for prostate cancer. Note: The information in this summary is no longer being updated and is provided for reference purposes only.

84

PC-SPES (PDQ)  

MedlinePLUS

... English | En espaol Search NCI Home Cancer Topics Clinical Trials Cancer Statistics Research & Funding News About NCI ... of Cancer Terms NCI Drug Dictionary Search for Clinical Trials NCI Publications Espaol Overview PC-SPES is ...

85

Connection between Group Based Quantum Tomography and Wavelet Transform in Banach Spaces  

Microsoft Academic Search

The intimate connection between the Banach space wavelet reconstruction method for each unitary representation of a given\\u000a group and some of well known quantum tomographies, such as: tomography of rotation group, Spinor tomography and tomography\\u000a of Unitary group, is established. Also both the atomic decomposition and Banach frame nature of these quantum tomographic\\u000a examples is revealed in details.

M. Mirzaee; M. Rezaei; M. A. Jafarizadeh

2007-01-01

86

Challenges in Teaching Space Physics to Different Target Groups From Space Weather Forecasters to Heavy-weight Theorists  

NASA Astrophysics Data System (ADS)

Plasma physics as the backbone of space physics is difficult and thus the space physics students need to have strong foundations in general physics, in particular in classical electrodynamics and thermodynamics, and master the basic mathematical tools for physicists. In many universities the number of students specializing in space physics at Master's and Doctoral levels is rather small and the students may have quite different preferences ranging from experimental approach to hard-core space plasma theory. This poses challenges in building up a study program that has both the variety and depth needed to motivate the best students to choose this field. At the University of Helsinki we require all beginning space physics students, regardless whether they enter the field as Master's or Doctoral degree students, to take a one-semester package consisting of plasma physics and its space applications. However, some compromises are necessary. For example, it is not at all clear, how thoroughly Landau damping should be taught at the first run or how deeply should the intricacies of collisionless reconnection be discussed. In both cases we have left the details to an optional course in advanced space physics, even with the risk that the student's appreciation of, e.g., reconnection may remain at the level of a magic wand. For learning experimental work, data analysis or computer simulations we have actively pursued arrangements for the Master's degree students to get a summer employments in active research groups, which usually lead to the Master's theses. All doctoral students are members of research groups and participate in experimental work, data analysis, simulation studies or theory development, or any combination of these. We emphasize strongly "learning by doing" all the way from the weekly home exercises during the lecture courses to the PhD theses which in Finland consist typically of 4-6 peer-reviewed articles with a comprehensive introductory part.

Koskinen, H. E.

2008-12-01

87

National facilities study. Volume 5: Space research and development facilities task group  

NASA Technical Reports Server (NTRS)

With the beginnings of the U.S. space program, there was a pressing need to develop facilities that could support the technology research and development, testing, and operations of evolving space systems. Redundancy in facilities that was once and advantage in providing flexibility and schedule accommodation is instead fast becoming a burden on scarce resources. As a result, there is a clear perception in many sectors that the U.S. has many space R&D facilities that are under-utilized and which are no longer cost-effective to maintain. At the same time, it is clear that the U.S. continues to possess many space R&D facilities which are the best -- or among the best -- in the world. In order to remain world class in key areas, careful assessment of current capabilities and planning for new facilities is needed. The National Facility Study (NFS) was initiated in 1992 to develop a comprehensive and integrated long-term plan for future aerospace facilities that meets current and projected government and commercial needs. In order to assess the nation's capability to support space research and development (R&D), a Space R&D Task Group was formed. The Task Group was co-chaired by NASA and DOD. The Task Group formed four major, technologically- and functionally- oriented working groups: Human and Machine Operations; Information and Communications; Propulsion and Power; and Materials, Structures, and Flight Dynamics. In addition to these groups, three supporting working groups were formed: Systems Engineering and Requirements; Strategy and Policy; and Costing Analysis. The Space R&D Task Group examined several hundred facilities against the template of a baseline mission and requirements model (developed in common with the Space Operations Task Group) and a set of excursions from the baseline. The model and excursions are described in Volume 3 of the NFS final report. In addition, as a part of the effort, the group examined key strategic issues associated with space R&D facilities planning for the U.S., and these are discussed in Section 4 of this volume.

1994-01-01

88

Group Momentum Space and Hopf Algebra Symmetries of Point Particles Coupled to 2+1 Gravity  

E-print Network

We present an in-depth investigation of the ${\\rm SL}(2,\\mathbb{R})$ momentum space describing point particles coupled to Einstein gravity in three space-time dimensions. We introduce different sets of coordinates on the group manifold and discuss their properties under Lorentz transformations. In particular we show how a certain set of coordinates exhibits an upper bound on the energy under deformed Lorentz boosts which saturate at the Planck energy. We discuss how this deformed symmetry framework is generally described by a quantum deformation of the Poincar\\'e group: the quantum double of ${\\rm SL}(2,\\mathbb{R})$. We then illustrate how the space of functions on the group manifold momentum space has a dual representation on a non-commutative space of coordinates via a (quantum) group Fourier transform. In this context we explore the connection between Weyl maps and different notions of (quantum) group Fourier transform appeared in the literature in the past years and establish relations between them.

Michele Arzano; Danilo Latini; Matteo Lotito

2014-03-12

89

Johnson Space Center's Risk and Reliability Analysis Group 2008 Annual Report  

NASA Technical Reports Server (NTRS)

The Johnson Space Center (JSC) Safety & Mission Assurance (S&MA) Directorate s Risk and Reliability Analysis Group provides both mathematical and engineering analysis expertise in the areas of Probabilistic Risk Assessment (PRA), Reliability and Maintainability (R&M) analysis, and data collection and analysis. The fundamental goal of this group is to provide National Aeronautics and Space Administration (NASA) decisionmakers with the necessary information to make informed decisions when evaluating personnel, flight hardware, and public safety concerns associated with current operating systems as well as with any future systems. The Analysis Group includes a staff of statistical and reliability experts with valuable backgrounds in the statistical, reliability, and engineering fields. This group includes JSC S&MA Analysis Branch personnel as well as S&MA support services contractors, such as Science Applications International Corporation (SAIC) and SoHaR. The Analysis Group s experience base includes nuclear power (both commercial and navy), manufacturing, Department of Defense, chemical, and shipping industries, as well as significant aerospace experience specifically in the Shuttle, International Space Station (ISS), and Constellation Programs. The Analysis Group partners with project and program offices, other NASA centers, NASA contractors, and universities to provide additional resources or information to the group when performing various analysis tasks. The JSC S&MA Analysis Group is recognized as a leader in risk and reliability analysis within the NASA community. Therefore, the Analysis Group is in high demand to help the Space Shuttle Program (SSP) continue to fly safely, assist in designing the next generation spacecraft for the Constellation Program (CxP), and promote advanced analytical techniques. The Analysis Section s tasks include teaching classes and instituting personnel qualification processes to enhance the professional abilities of our analysts as well as performing major probabilistic assessments used to support flight rationale and help establish program requirements. During 2008, the Analysis Group performed more than 70 assessments. Although all these assessments were important, some were instrumental in the decisionmaking processes for the Shuttle and Constellation Programs. Two of the more significant tasks were the Space Transportation System (STS)-122 Low Level Cutoff PRA for the SSP and the Orion Pad Abort One (PA-1) PRA for the CxP. These two activities, along with the numerous other tasks the Analysis Group performed in 2008, are summarized in this report. This report also highlights several ongoing and upcoming efforts to provide crucial statistical and probabilistic assessments, such as the Extravehicular Activity (EVA) PRA for the Hubble Space Telescope service mission and the first fully integrated PRAs for the CxP's Lunar Sortie and ISS missions.

Valentine, Mark; Boyer, Roger; Cross, Bob; Hamlin, Teri; Roelant, Henk; Stewart, Mike; Bigler, Mark; Winter, Scott; Reistle, Bruce; Heydorn,Dick

2009-01-01

90

Elementary Energy Bands in Crystalline Solids:. Space Groups with 3-DIMENSIONAL Strata Only  

NASA Astrophysics Data System (ADS)

Elementary energy bands in solids are defined generalizing the notion of simple and composite energy bands. All energy branches of elementary energy bands are connected. Following the connectivity of the energy branches in elementary energy bands, a new notion of unavoidable degeneracy is established, for which the crossings can be moved but not removed. This degeneracy does not depend on the particular shape of the potential and is present in all crystals of some given space group symmetry. A review of unavoidable degeneracy is given for all 13 space groups of special kind in 3-dimensions whose only Wyckoff position (symmetry center in the crystal) is of trivial symmetry.

Michel, L.; Zak, J.

2001-04-01

91

The Local Population of White Dwarfs within 25 pc  

NASA Astrophysics Data System (ADS)

We have extended the detailed survey of the local white dwarf population from 20 pc to 25 pc, effectively doubling the sample volume to now include 231 stars. The present 25 pc has an estimated completeness of 70% (the corresponding 20 pc sample is now 85% complete). The space density of white dwarfs remains at 4.8 0.5 x 10-3 pc-3. There exists a curious excess of single stars in the sample 70% vs 30% in systems with one or more companions. A pronounced apparent deficiency remains between the eleven known Sirius-like systems present in the 20 pc sample and only a single such system presently known in the extended 25 pc sample. Also demonstrated, using explicit individual white dwarf cooling ages, is the feasibility of estimating the white dwarf birth rates over the last ~ 5 Gyr.This work is supported by NSF grant AST-1413537

Holberg, Jay B.; Oswalt, Terry D.; Sion, Edward M.

2015-01-01

92

Homotopy colimits of classifying spaces of abelian subgroups of a finite group.  

E-print Network

The classifying space BG of a topological group $G$ can be filtered by a sequence of subspaces $B(q,G)$, using the descending central series of free groups. If $G$ is finite, describing them as homotopy colimits is convenient when applying homotopy theoretic methods. In this paper we introduce natural subspaces $B(q,G)_p$ of $B(q,G)$ defined for a fixed prime $p$. We show that $B(q,G)$ is stably homotopy equivalent to a wedge of $B(q,G)_p$ as $p$ runs over the primes dividing the order of $G$. Colimits of abelian groups play an important role in understanding the homotopy type of these spaces. Extraspecial $2$-groups are key examples, for which these colimits turn out to be finite. We prove that for extraspecial 2-groups, $B(2,G)$ does not have the homotopy type of a $K(\\pi,1)$ space. For a finite group $G$, we compute the complex K-theory of $B(2,G)$ modulo torsion.

Cihan Okay.

93

Space group selection for crystal structure prediction of solvates{ Aurora J. Cruz Cabeza,a  

E-print Network

Space group selection for crystal structure prediction of solvates{ Aurora J. Cruz Cabeza,a Elna with common solvents are presented to assist crystal structure prediction calculations on these complex systems. Introduction Many programs for the computer generation of crystal structures (e.g. UPACK,1

de Gispert, Adrià

94

Cooperation Without Memory or Space: Tags, Groups and the Prisoner's Dilemma  

E-print Network

Cooperation Without Memory or Space: Tags, Groups and the Prisoner's Dilemma David Hales Department] model demonstrated that image scoring produces high cooperation between strangers in the Prisoner] reproduction of strategies is population wide. Contrary to previous tag models [15] cooperation is demonstrated

Hales, David

95

Nuclear safety policy working group recommendations on nuclear propulsion safety for the space exploration initiative  

Microsoft Academic Search

An interagency Nuclear Safety Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program. These recommendations, which are contained in this report, should facilitate the implementation of mission planning and conceptual design studies. The NSPWG has recommended a top-level policy to provide the guiding principles for the development

Albert C. Marshall; James H. Lee; William H. McCulloch; J. Charles Sawyer Jr.; Robert A. Bari; Hatice S. Cullingford; Alva C. Hardy; George F. Niederauer; Kerry Remp; John W. Rice

1993-01-01

96

On the Construction of Space-time Hamiltonian Constellations from Group Codes  

E-print Network

On the Construction of Space-time Hamiltonian Constellations from Group Codes Terasan Niyomsataya, Canada K1N 6N5 mnevins@uottawa.ca Abstract-- Full diversity signal constellations for any numbers in this paper. The diversity product of a 2?2 Hamiltonian constellation equals one half of the Euclidean

Nevins, Monica

97

On The K-Ring of the Classifying Space of the Symmetric Group on Four Letters.  

E-print Network

We describe $K(BS_4)$ and make a connection of the order of the bundle induced from the standart representation over the four dimensional skeleton of $BS_4$ with the stable homotopy group $\\pi_3^s=Z_{24}$ explaining the reasons of this connection by pulling this bundle over lens spaces.

Mehmet Kirdar

98

REQUEST FOR LEASED SPACE 3. FROM: (REQUESTING DIVISION) 4. FOR: (USER GROUP)  

E-print Network

REQUEST FOR LEASED SPACE 1. DATE 2. TO: 3. FROM: (REQUESTING DIVISION) 4. FOR: (USER GROUP) CONTACT LEASING ACTION Advertise Solicitation For Lease 18. REAL ESTATE Other (See attached)Initiate Short Form Lease Initiate Sole Source DATE APPROVED DATE19. DEPARTMENT OF ENERGY PRINT NAME AND TITLEAPPROVAL

99

Group Decision Fiascoes Continue: Space Shuttle Challenger and a Revised Groupthink Framework  

Microsoft Academic Search

This paper reviews the decision situation surrounding the decision to launch the space shuttle Challenger in January 1986 in the light of the groupthink hypothesis. A revised framework is presented that proposes time and leadership style as moderators of the manner in which group characteristics lead to groupthink symptoms.

Gregory Moorhead; Richard Ference; Chris P. Neck

1991-01-01

100

PC Expo 2001  

NSDL National Science Digital Library

PC Expo 2001 wrapped up yesterday, and CNET offers a recap and its best of show awards at this site. Best of show categories include personal technology, emerging technology, enterprise product, business solution, and best overall. Each listing contains a brief description and a video segment. Also at the site are numerous short articles on various products and trends at the expo.

101

Algorithms for deriving crystallographic space-group information. II: Treatment of special positions  

SciTech Connect

Algorithms for the treatment of special positions in 3-dimensional crystallographic space groups are presented. These include an algorithm for the determination of the site-symmetry group given the coordinates of a point, an algorithm for the determination of the exact location of the nearest special position, an algorithm for the assignment of a Wyckoff letter given the site-symmetry group, and an alternative algorithm for the assignment of a Wyckoff letter given the coordinates of a point directly. All algorithms are implemented in ISO C++ and are integrated into the Computational Crystallography Toolbox. The source code is freely available.

Grosse-Kunstleve, Ralf W.; Adams, Paul D.

2001-10-05

102

Algorithms for deriving crystallographic space-group information. II. Treatment of special positions.  

PubMed

Algorithms for the treatment of special positions in three-dimensional crystallographic space groups are presented. These include an algorithm for the determination of the site-symmetry group given the coordinates of a point, an algorithm for the determination of the exact location of the nearest special position, an algorithm for the assignment of a Wyckoff letter given the site-symmetry group, and an alternative algorithm for the assignment of a Wyckoff letter given the coordinates of a point directly. All algorithms are implemented in ISO C++ and are integrated into the Computational Crystallography Toolbox. The source code is freely available. PMID:11752765

Grosse-Kunstleve, R W; Adams, P D

2002-01-01

103

Future In-Space Operations (FISO): A Working Group and Community Engagement  

NASA Technical Reports Server (NTRS)

Long-duration human capabilities beyond low Earth orbit (LEO), either in support of or as an alternative to lunar surface operations, have been assessed at least since the late 1960s. Over the next few months, we will present short histories of concepts for long-duration, free-space human habitation beyond LEO from the end of the Apollo program to the Decadal Planning Team (DPT)/NASA Exploration Team (NExT), which was active in 1999 2000 (see Forging a vision: NASA s Decadal Planning Team and the origins of the Vision for Space Exploration , The Space Review, December 19, 2005). Here we summarize the brief existence of the Future In-Space Operations (FISO) working group in 2005 2006 and its successor, a telecon-based colloquium series, which we co-moderate.

Thronson, Harley; Lester, Dan

2013-01-01

104

Space and time: an impact of spatial separation, apparent motion, and perceptual grouping on TOJ performance.  

PubMed

This study explored the effects of spacing and objecthood (ie grouping based on closure) on temporal order judgment (TOJ) with displays that either involved successive onset of the target stimuli, resulting in apparent motion (experiments 1 and 2), or included simultaneous onset but successive shortening of the stimuli, and therefore did not result in apparent motion (experiment 3). We found a robust effect of spatial separation whose nature depended on whether or not the display allowed the emergence of illusory motion. Specifically, with apparent motion TOJ was best with the smallest spacing, but without it TOJ was worst with the smallest spacing. Moreover, overall accuracy was better with, than without, apparent motion. A small effect of objecthood--poorer TOJ performance when the elements formed an object--emerged only when spacing was not manipulated. These findings suggest that different mechanisms mediate temporal processing when we have access to motion information than when we do not. PMID:23964380

Baruch, Orit; Yeshurun, Yaffa; Shore, David I

2013-01-01

105

New unifying procedure for PC index calculations.  

NASA Astrophysics Data System (ADS)

The Polar Cap (PC) index is a controversial topic within the IAGA scientific community. Since 1997 discussions of the validity of the index to be endorsed as an official IAGA index have ensued. Currently, there are now the three separate PC index versions constructed from the different procedures used at the three institutes: the Arctic and Antarctic Research Institute (AARI), the Danish Meteorological Institute (DMI), and the Danish National Space Institute (DTU Space). It is demonstrated in this presentation, that two consistent unifying procedures can be built from the best elements of the three different versions. One procedure uses a set of coefficients aimed at the calculation of final PC index values to be accepted by IAGA. The other procedure uses coefficients aimed at on-line real-time production of preliminary PC index values for Space Weather monitoring applications. For each of the two cases the same procedure is used for the northern (PCN) and the southern (PCS) polar cap indices, and the derived PCN and PCS coefficients are similar.

Stauning, P.

2012-04-01

106

Communication: Active space decomposition with multiple sites: Density matrix renormalization group algorithm  

NASA Astrophysics Data System (ADS)

We extend the active space decomposition method, recently developed by us, to more than two active sites using the density matrix renormalization group algorithm. The fragment wave functions are described by complete or restricted active-space wave functions. Numerical results are shown on a benzene pentamer and a perylene diimide trimer. It is found that the truncation errors in our method decrease almost exponentially with respect to the number of renormalization states M, allowing for numerically exact calculations (to a few ?Eh or less) with M = 128 in both cases. This rapid convergence is because the renormalization steps are used only for the interfragment electron correlation.

Parker, Shane M.; Shiozaki, Toru

2014-12-01

107

The space shuttle payload planning working groups. Volume 7: Earth observations  

NASA Technical Reports Server (NTRS)

The findings of the Earth Observations working group of the space shuttle payload planning activity are presented. The objectives of the Earth Observation experiments are: (1) establishment of quantitative relationships between observable parameters and geophysical variables, (2) development, test, calibration, and evaluation of eventual flight instruments in experimental space flight missions, (3) demonstration of the operational utility of specific observation concepts or techniques as information inputs needed for taking actions, and (4) deployment of prototype and follow-on operational Earth Observation systems. The basic payload capability, mission duration, launch sites, inclinations, and payload limitations are defined.

1973-01-01

108

The space shuttle payload planning working groups. Volume 8: Earth and ocean physics  

NASA Technical Reports Server (NTRS)

The findings and recommendations of the Earth and Ocean Physics working group of the space shuttle payload planning activity are presented. The requirements for the space shuttle mission are defined as: (1) precision measurement for earth and ocean physics experiments, (2) development and demonstration of new and improved sensors and analytical techniques, (3) acquisition of surface truth data for evaluation of new measurement techniques, (4) conduct of critical experiments to validate geophysical phenomena and instrumental results, and (5) development and validation of analytical/experimental models for global ocean dynamics and solid earth dynamics/earthquake prediction. Tables of data are presented to show the flight schedule estimated costs, and the mission model.

1973-01-01

109

Fredholm and spectral properties of Toeplitz operators on H{sup p} spaces over ordered groups  

SciTech Connect

We consider Toeplitz operators on the spaces H{sup p}(G), 1< p<{infinity}, associated with a compact connected Abelian group G whose character group is ordered and, in the case of total order, prove a theorem on the Fredholm index for those operators which have continuous symbols which generalizes the classical Gohberg-Krein theorem. The results thus obtained are applied to the spectral theory of Toeplitz operators and examples where the index is evaluated explicitly are considered. Bibliography: 22 titles.

Mirotin, Adolf R [Gomel State University, Gomel (Belarus)

2011-05-31

110

Real space renormalization group for twisted lattice =4 super Yang-Mills  

NASA Astrophysics Data System (ADS)

A necessary ingredient for our previous results on the form of the long distance effective action of the twisted lattice =4 super Yang-Mills theory is the existence of a real space renormalization group which preserves the lattice structure, both the symmetries and the geometric interpretation of the fields. In this brief article we provide an explicit example of such a blocking scheme and illustrate its practicality in the context of a small scale Monte Carlo renormalization group calculation. We also discuss the implications of this result, and the possible ways in which to use it in order to obtain further information about the long distance theory.

Catterall, Simon; Giedt, Joel

2014-11-01

111

Science Requirements Working Group (SRWG) in float zone materials processing in space: A review  

NASA Technical Reports Server (NTRS)

A summary and history of the Float Zone Working Group was presented. The functions of this working group are to: provide an informal forum of scientific investigators for the exchange of information and ideas in the approach of the solution of common problems in float zone processing, help plan the research and development necessary to place the float zone process on a firm base of scientific understanding and advanced technological development, establish the science requirements for the AFZES for Spacelab, and seek ways to maximize the advantages of the space environment in the pursuit of these goals.

Fowle, A. A.

1980-01-01

112

Range Commanders Council Meteorology Group 88th Meeting: NASA Marshall Space Flight Center Task Report, 2004  

NASA Technical Reports Server (NTRS)

Supported Return-to-Flight activities by providing surface climate data from Kennedy Space Center used primarily for ice and dew formation studies, and upper air wind analysis primarily used for ascent loads analyses. The MSFC Environments Group's Terrestrial and Planetary Environments Team documented Space Shuttle day-of-launch support activities by publishing a document in support of SSP Return-to-Flight activities entitled "Space Shuttle Program Flight Operations Support". The team also formalized the Shuttle Natural Environments Technical Panel and chaired the first special session of the SSP Natural Environments Panel meeting at KSC, November 4-7,2003.58 participants from NASA, DOD and other government agencies from across the country attended the meeting.

Roberts, Barry C.

2004-01-01

113

Constructive Axiomatic Approach to the Determination of the Orbit Spaces of Coregular Compact Linear Groups  

Microsoft Academic Search

We review the proposal of a constructive axiomatic approach to the determination of the orbit spaces of all the real compact linear groups, obtained through the computation of a metric matrix \\u000a\\u000a\\u000a, which is defined only in terms of the scalar products between the gradients ?p1(x),.?.?.,?pq(x) of the elements of a minimal integrity basis (MIB) for the ring R[Rn]G of

G. Sartori; G. Valente

2005-01-01

114

Remote File PC Users Guide  

E-print Network

UTS: ITD Remote File Access 2010 PC Users Guide V3.0 #12;UTS:ITD Remote File Access: PC Users Guide:ITD Remote File Access: PC Users Guide v3.0 2010 3 1. What is Remote File Access? UTS Remote File Access. Remote File Access will allow staff to view and transfer files between UTS network file storage

University of Technology, Sydney

115

One dimensional zone center phonons in $O_{h}$ space group  

E-print Network

Motivated by experiments, we performed a systematic study on the one dimensional zone center phonons in $O_{h}$ space groups. All the one dimensional phonon modes for different Wyckoff positions are tabulated. We show that at least four (inequivalent) atoms (in one set of Wyckoff positions) are needed to carry a single one dimensional phonon. A general restriction rule on the number of atoms and the number of one dimensional phonons is obtained. The same restriction applies to phonons of all cubic crystal systems ($T$, $T_{h}$, $T_{d}$, $O$, $O_{h}$) and to magnons for crystals whose unitary symmetry elements are in ($T$, $T_{h}$, $T_{d}$, $O$, $O_{h}$). Crystals with $A15$ structure are found to satisfy experimental requirements (to have a $\\Gamma_{2}^{+}$ phonon) while most crystals of $O_{h}$ space groups do not. $A15$ is also used to demonstrate the rules we found regarding the phonon structure in $O_{h}$ space groups.

Jian Li; Jiufeng J. Tu; Joseph L. Birman

2014-03-04

116

The redshift-space neighborhoods of 36 loose groups of galaxies. 1: The data  

NASA Technical Reports Server (NTRS)

We have selected 36 loose groups of galaxies (RGH89) with at least five members, and with mean redshift average value of CZ is greater than 3200 km/s. These groups all lie within the first two slices of the CfA redshift survey 8(sup h) less than or equal to alpha less than or equal to 17(sup h) and 26.5 deg less than or equal to delta less than or equal to 38.5 deg). For each of these groups, we define the redshift-space neighborhood as a region centered on the group coordinates and delimited by a circle of projected radius R(sub cir) = 1.5/h Mpc on the sky, and by a velocity interval delta (sub cz) = 3000 km/s. Here we give the redshifts of 334 galaxies in these redshift-space neighborhoods. For completeness, we also give the redshifts of the 232 original members. These data include 199 new redshifts. We demonstrate that these samples of fainter galaxies significantly increase the number of members.

Ramella, Massimo; Geller, Margaret J.; Hurchra, John P.; Thorstensen, John R.

1995-01-01

117

Topological entropy and renormalization group flow in 3-dimensional spherical spaces  

NASA Astrophysics Data System (ADS)

We analyze the renormalization group (RG) flow of the temperature independent term of the entropy in the high temperature limit ?/a ? 1 of a massive field theory in 3-dimensional spherical spaces, M 3, with constant curvature 6 /a 2. For masses lower than , this term can be identified with the free energy of the same theory on M 3 considered as a 3-dimensional Euclidean space-time. The non-extensive part of this free energy, S hol, is generated by the holonomy of the spatial metric connection. We show that for homogeneous spherical spaces the holonomy entropy S hol decreases monotonically when the RG scale flows to the infrared. At the conformal fixed points the values of the holonomy entropy do coincide with the genuine topological entropies recently introduced. The monotonic behavior of the RG flow leads to an inequality between the topological entropies of the conformal field theories connected by such flow, i.e. S {top/ UV } > S {top/ IR }. From a 3-dimensional viewpoint the same term arises in the 3-dimensional Euclidean effective action and has the same monotonic behavior under the RG group flow. We conjecture that such monotonic behavior is generic, which would give rise to a 3-dimensional generalization of the c-theorem, along the lines of the 2-dimensional c-theorem and the 4-dimensional a-theorem. The conjecture is related to recent formulations of the F -theorem. In particular, the holonomy entropy on lens spaces is directly related to the topological Rnyi entanglement entropy on disks of 2-dimensional flat spaces.

Asorey, M.; Beneventano, C. G.; Cavero-Pelez, I.; D'Ascanio, D.; Santangelo, E. M.

2015-01-01

118

A Perceptual Phonetic Similarity Space for Languages: Evidence from Five Native Language Listener Groups1  

PubMed Central

The goal of the present study was to devise a means of representing languages in a perceptual similarity space based on their overall phonetic similarity. In Experiment 1, native English listeners performed a free classification task in which they grouped 17 diverse languages based on their perceived phonetic similarity. A similarity matrix of the grouping patterns was then submitted to clustering and multidimensional scaling analyses. In Experiment 2, an independent group of native English listeners sorted the group of 17 languages in terms of their distance from English. Experiment 3 repeated Experiment 2 with four groups of non-native English listeners: Dutch, Mandarin, Turkish and Korean listeners. Taken together, the results of these three experiments represent a step towards establishing an approach to assessing the overall phonetic similarity of languages. This approach could potentially provide the basis for developing predictions regarding foreign-accented speech intelligibility for various listener groups, and regarding speech perception accuracy in the context of background noise in various languages. PMID:21179563

Bradlow, Ann; Clopper, Cynthia; Smiljanic, Rajka; Walter, Mary Ann

2010-01-01

119

The Community-based Organizations Working Group of the Space Science Education Support Network  

NASA Astrophysics Data System (ADS)

The NASA Space Science Support Network Community-based Organizations Working Group (CBOWG) has been working for the past two years on issues surrounding afterschool programs and programs for youth (e.g., Girl Scouts, Boy Scouts, Boys and Girls Clubs, 4-H, summer camps, afterschool and weekend programs for various ages, programs with emphases on minority youth). In this session the co-leaders of the CBOWG will discuss the challenges of working with community-based organizations on a regional or national level. We will highlight some ties that we have forged with the National Institute for Out of School Time (NIOST) and the National Afterschool Association (NAA). We will also talk about efforts to coordinate how various entities within NASA cooperate with community-based organizations to serve the best interests of these groups. We will give a couple of examples of how NASA space science organizations have partnered with community-based organizations. The session will include some handouts of information and resources that the CBOWG has found useful in developing an understanding of this segment of informal education groups. We would like to thank NASA for providing resources to support the work of the CBOWG.

Lutz, J. H.; Lowes, L. L.; Asplund, S.

2004-12-01

120

Unfolding of electronic structure through induced representations of space groups: Application to Fe-based superconductors  

NASA Astrophysics Data System (ADS)

We revisit the problem that relevant parts of band structures for a given cell choice can reflect exact or approximate higher symmetries of subsystems in the cell and can therefore be significantly simplified by an unfolding procedure that recovers the higher symmetry. We show that band-structure unfolding can be understood as projection onto induced irreducible representations of a group obtained by extending the original group of translations with a number of additional symmetry operations. The resulting framework allows us to define a generalized unfolding procedure that includes the point group operations and can be applied to any quantity in the reciprocal space. The unfolding of the Brillouin zone follows naturally from the properties of the induced irreducible representations. In this context, we also introduce a procedure to derive tight-binding models of reduced dimensionality by making use of point group symmetries. Further, we show that careful consideration of unfolding has important consequences on the interpretation of angle-resolved photoemission experiments. Finally, we apply the unfolding procedure to various representative examples of Fe-based superconductor compounds and show that the one-iron picture arises as an irreducible representation of the glide-reflection group, and we comment on the consequences for the interpretation of one-iron versus two-iron Brillouin zone representations.

Tomi?, Milan; Jeschke, Harald O.; Valent, Roser

2014-11-01

121

Inhibition of Prohormone Convertases PC1/3 and PC2 by 2,5-Dideoxystreptamine Derivatives  

PubMed Central

The prohormone convertases PC1/3 and PC2 are eukaryotic serine proteases involved in the proteolytic maturation of peptide hormone precursors and are implicated in a variety of pathological conditions, including obesity, diabetes, and neurodegenerative diseases. In this work, we screened 45 compounds obtained by derivatization of a 2,5-dideoxystreptamine scaffold with guanidinyl and aryl substitutions for convertase inhibition. We identified four promising PC1/3 competitive inhibitors and three PC2 inhibitors that exhibited various inhibition mechanisms (competitive, noncompetitive, and mixed), with sub- and low micromolar inhibitory potency against a fluorogenic substrate. Low micromolar concentrations of certain compounds blocked the processing of the physiological substrate proglucagon. The best PC2 inhibitor effectively inhibited glucagon synthesis, a known PC2-mediated process, in a pancreatic cell line; no cytotoxicity was observed. We also identified compounds that were able to stimulate both 87 kDa PC1/3 and PC2 activity, behavior related to the presence of aryl groups on the dideoxystreptamine scaffold. By contrast, inhibitory activity was associated with the presence of guanidinyl groups. Molecular modeling revealed interactions of the PC1/3 inhibitors with the active site that suggest structural modifications to further enhance potency. In support of kinetic data suggesting that PC2 inhibition probably occurs via an allosteric mechanism, we identified several possible allosteric binding sites using computational searches. It is noteworthy that one compound was found to both inhibit PC2 and stimulate PC1/3. Because glucagon acts in functional opposition to insulin in blood glucose homeostasis, blocking glucagon formation and enhancing proinsulin cleavage with a single compound could represent an attractive therapeutic approach in diabetes. PMID:22169851

Vivoli, Mirella; Caulfield, Thomas R.; Martnez-Mayorga, Karina; Johnson, Alan T.; Jiao, Guan-Sheng

2012-01-01

122

The space shuttle payload planning working groups. Volume 5: Solar physics  

NASA Technical Reports Server (NTRS)

The findings of the Solar Physics working group of the space shuttle payload planning activity are presented. The areas to be investigated by the solar physics experiments are: (1) the production of mechanical energy in the subphotospheric layers and its transport and dissipation in the upper layers of the atmosphere, (2) the mass flux from the subphotospheric layers into the chromosphere and corona and beyond the solar wind, (3) solar activity and its relationship to magnetic fields, and (4) the production of solar flares. The approach to be followed in conducting the experiments and the equipment required are defined.

1973-01-01

123

A Fun and Effective Exercise for Understanding Lattices and Space Groups  

NSDL National Science Digital Library

This activity uses figures from Francois Brisse as Esher drawings to teach students about 2-dimensional symmetry, especially involving translation. This exercise is based on discovery learning. Students need little introduction to lattices and space groups. They can figure things out for themselves. For example, they will figure out what a glide plane is, and if you tell them ahead of time it takes away from the learning experience. The last question, which asks them to make their own symmetrical drawings, is difficult but often leads to some spectacular results.

Dexter Perkins

124

The space shuttle payload planning working groups. Volume 4: Life sciences  

NASA Technical Reports Server (NTRS)

The findings of the Life Sciences working group of the space shuttle payload planning activity are presented. The objectives of the Life Sciences investigations are: (1) to continue the research directed at understanding the origin of life and the search for extraterrestrial evidence of life, (2) biomedical research to understand mechanisms and provide criteria for support of manned flight, (3) technology development for life support, protective systems, and work aids for providing environmental control, and (4) to study basic biological functions at all levels or organization influenced by gravity, radiation, and circadian rhythms. Examples of candidate experimental schedules and the experimental package functional requirements are included.

1973-01-01

125

Taut foliations and the actions of fundamental groups on leaf spaces and universal circles  

E-print Network

Let $F$ be a leafwise hyperbolic taut foliation of a closed 3-manifold $M$ and let $L$ be the leaf space of the pullback of $F$ to the universal cover of $M$. We show that if $F$ has branching, then the natural action of $\\pi_1(M)$ on $L$ is faithful. We also show that if $F$ has a finite branch locus $B$ whose stabilizer acts on $B$ nontrivially, then the stabilizer is an infinite cyclic group generated by an indivisible element of $\\pi_1(M)$.

Kano, Yosuke

2012-01-01

126

Benzyltripropylammonium bromide: a structure in polar space group P4(2)bc.  

PubMed

Crystals of the title compound, C(16)H(28)N(+).Br(-), were grown from solution in a mixture of acetone and propan-2-ol by slow evaporation. The structure was solved in the polar space group P4(2)bc with five moieties in the asymmetric unit, namely two benzyltripropylammonium cations in general positions, and two Br(-) anions in special Wyckoff positions (4a2. and 4b2.) and one in a general position. The structure consists of two kinds of molecular columns parallel to c, built of cations connected through C-H.pi hydrogen bonds and stabilized by weak C-H.Br interactions. PMID:14532666

Hodorowicz, Maciej A; Czapkiewicz, Jan; Stadnicka, Katarzyna

2003-10-01

127

GFI - EASY PC GRAPHICS  

NASA Technical Reports Server (NTRS)

Easy PC Graphics (GFI) is a graphical plot program that permits data to be easily and flexibly plotted. Data is input in a standard format which allows easy data entry and evaluation. Multiple dependent axes are also supported. The program may either be run in a stand alone mode or be embedded in the user's own software. Automatic scaling is built in for several logarithmic and decibel scales. New scales are easily incorporated into the code through the use of object-oriented programming techniques. For the autoscale routines and the actual plotting code, data is not retrieved directly from a file, but a "method" delivers the data, performing scaling as appropriate. Each object (variable) has state information which selects its own scaling. GFI is written in Turbo Pascal version 6.0 for IBM PC compatible computers running MS-DOS. The source code will only compile properly with the Turbo Pascal v. 6.0 or v. 7.0 compilers; however, an executable is provided on the distribution disk. This executable requires at least 64K of RAM and DOS 3.1 or higher, as well as an HP LaserJet printer to print output plots. The standard distribution medium for this program is one 5.25 inch 360K MS-DOS format diskette. The contents of the diskette are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. An electronic copy of the documentation is provided on the distribution medium in ASCII format. GFI was developed in 1993.

Katz, R. B.

1994-01-01

128

Hubble Space Telescope Images of Stephan's Quintet: Star Cluster Formation in a Compact Group Environment  

E-print Network

Analysis of Hubble Space Telescope/Wide Field Planetary Camera 2 images of Stephan's Quintet, Hickson Compact Group 92, yielded 115 candidate star clusters (with V-I < 1.5). Unlike in merger remants, the cluster candidates in Stephan's Quintet are not clustered in the inner regions of the galaxies; they are spread over the debris and surrounding area. Specifically, these sources are located in the long sweeping tail and spiral arms of NGC 7319, in the tidal debris of NGC 7318B/A, and in the intragroup starburst region north of these galaxies. Analysis of the colors of the clusters indicates several distinct epochs of star formation that appear to trace the complex history of dynamical interactions in this compact group.

S. C. Gallagher; J. C. Charlton; S. D. Hunsberger; D. Zaritsky; B. C. Whitmore

2001-03-31

129

Intraspecific variation in space use, group size, and mating systems of caviomorph rodents  

PubMed Central

Intraspecific variation in social systems is widely recognized across many taxa, and specific models, including polygamy potential, resource defense, and resource dispersion, have been developed to explain the relationship between ecological variation and social organization. Although mammals from temperate North America and Eurasia have provided many insights into this relationship, rodents from the Neotropics and temperate South America have largely been ignored. In this review we focus on reports documenting intraspecific variation in spacing systems, group size, and mating systems of caviomorphs. This large group of New World hystricognath rodents occupies a diverse array of habitats; thus, members of the same species potentially exhibit different social systems in response to different ecological conditions. Spatial patterns vary in response to a diverse array of factors, including predation, food availability, population density, and soil characteristics. Changes in group size typically correlate with changes in resource availability, particularly food. Mating systems generally reflect the ability of males to control access to females, which may depend on population density or food distribution. In general, social organization in caviomorphs fits predictions of resource-based models; however, most studies have been purely observational, involving small numbers of animals over short time periods and reporting qualitative rather than quantitative levels of ecological correlates. In future studies the use of molecular techniques and controlled, experimental manipulations can increase our understanding of intraspecific variation in caviomorph social systems. This understudied group of rodents offers excellent opportunities to provide insights into the influence of ecological conditions on behavior such as social systems. PMID:22328790

Maher, Christine R.; Burger, Joseph Robert

2012-01-01

130

Quantization of the optical phase space in terms of the group  

NASA Astrophysics Data System (ADS)

The problem of quantizing properly the canonical pair angle and action variables, and I, is almost as old as quantum mechanics itself and since decades an intensively debated but still unresolved issue in quantum optics. The present paper proposes a new approach to the problem, namely quantization in terms of the group SO(1,2): The crucial point is that the phase space %200%5C%7D%24%5Cend%7Bdocument%7D"> has the global structure (a simple cone) and cannot be quantized in the conventional manner. As the group SO(1,2) acts transitively, effectively and Hamilton-like on that space its irreducible unitary representations of the positive discrete series provide the appropriate quantum theoretical framework. The phase space has the conic structure of an orbifold . That structure is closely related to a Z2 gauge symmetry which corresponds to the center of a 2-fold covering of SO(1,2), the symplectic group . The basic variables on the phase space are the functions h0 = I , h1 = I cos and h2 = -I sin the Poisson brackets of which obey the Lie algebra . In the quantum theory they are represented by the self-adjoint Lie algebra generators K0, K1, and K2 of a unitary representation, where K0 has the spectrum {k + n, n = 0, 1, ...; k > 0}. A crucial prediction is that the classical Pythagorean relation h12 + h22 = h02 can be violated in the quantum theory. For each representation one can define three different types of coherent states the complex phases of which may be measured by means of the operators K1 and K2 alone without introducing any new phase operators! The SO(1,2) structure of optical squeezing and interference properties as well as that of the harmonic oscillator are analyzed in detail. The additional coherent states can be used for the introduction of (Husimi type) Q distributions and (Sudarshan-Glauber type) P representations of the density operator. The three operators K0, K1, and K2 are fundamental in the sense that one can construct composite position and momentum operators out of them! The new framework poses quite a number of fascinating experimental and theoretical challenges.

Kastrup, H. A.

2003-10-01

131

Space group symmetry fractionalization in a family of exactly solvable models with Z2 topological order  

E-print Network

We study square lattice space group symmetry fractionalization in a family of exactly solvable models with $\\mathbb{Z}_2$ topological order in two dimensions. In particular, we have obtained a complete understanding of which distinct types of symmetry fractionalization (symmetry classes) can be realized within this class of models, which are generalizations of Kitaev's $\\mathbb{Z}_2$ toric code to arbitrary lattices. This question is motivated by earlier work of A. M. Essin and one of us (M. H.), where the idea of symmetry classification was laid out, and which, for square lattice symmetry, produces 2080 symmetry classes consistent with the fusion rules of $\\mathbb{Z}_2$ topological order. This approach does not produce a physical model for each symmetry class, and indeed there are reasons to believe that some symmetry classes may not be realizable in strictly two-dimensional systems, thus raising the question of which classes are in fact possible. While our understanding is limited to a restricted class of models, it is complete in the sense that for each of the 2080 possible symmetry classes, we either prove rigorously that the class cannot be realized in our family of models, or we give an explicit model realizing the class. We thus find that exactly 487 symmetry classes are realized in the family of models considered. With a more restrictive type of symmetry action, where space group operations act trivially in the internal Hilbert space of each spin degree of freedom, we find that exactly 82 symmetry classes are realized. In addition, we present a single model that realizes all $2^6 = 64$ types of symmetry fractionalization allowed for a single anyon species ($\\mathbb{Z}_2$ charge excitation), as the parameters in the Hamiltonian are varied. The paper concludes with a summary and a discussion of two results pertaining to more general bosonic models.

Hao Song; Michael Hermele

2015-02-05

132

A PC based fault diagnosis expert system  

NASA Technical Reports Server (NTRS)

The Integrated Status Assessment (ISA) prototype expert system performs system level fault diagnosis using rules and models created by the user. The ISA evolved from concepts to a stand-alone demonstration prototype using OPS5 on a LISP Machine. The LISP based prototype was rewritten in C and the C Language Integrated Production System (CLIPS) to run on a Personal Computer (PC) and a graphics workstation. The ISA prototype has been used to demonstrate fault diagnosis functions of Space Station Freedom's Operation Management System (OMS). This paper describes the development of the ISA prototype from early concepts to the current PC/workstation version used today and describes future areas of development for the prototype.

Marsh, Christopher A.

1990-01-01

133

Facilitated spin models in one dimension: a real-space renormalization group study.  

PubMed

We use a real-space renormalization group (RSRG) to study the low-temperature dynamics of kinetically constrained Ising chains (KCICs). We consider the cases of the Fredrickson-Andersen (FA) model, the East model, and the partially asymmetric KCIC. We show that the RSRG allows one to obtain in a unified manner the dynamical properties of these models near their zero-temperature critical points. These properties include the dynamic exponent, the growth of dynamical length scales, and the behavior of the excitation density near criticality. For the partially asymmetric chain, the RG predicts a crossover, on sufficiently large length and time scales, from East-like to FA-like behavior. Our results agree with the known results for KCICs obtained by other methods. PMID:15600482

Whitelam, Stephen; Garrahan, Juan P

2004-10-01

134

Nuclear safety policy working group recommendations on nuclear propulsion safety for the space exploration initiative  

NASA Technical Reports Server (NTRS)

An interagency Nuclear Safety Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program. These recommendations, which are contained in this report, should facilitate the implementation of mission planning and conceptual design studies. The NSPWG has recommended a top-level policy to provide the guiding principles for the development and implementation of the SEI nuclear propulsion safety program. In addition, the NSPWG has reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. These recommendations should be useful for the development of the program's top-level requirements for safety functions (referred to as Safety Functional Requirements). The safety requirements and guidelines address the following topics: reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, safeguards, risk/reliability, operational safety, ground testing, and other considerations.

Marshall, Albert C.; Lee, James H.; Mcculloch, William H.; Sawyer, J. Charles, Jr.; Bari, Robert A.; Cullingford, Hatice S.; Hardy, Alva C.; Niederauer, George F.; Remp, Kerry; Rice, John W.

1993-01-01

135

Alveolar Gas - PC Version  

NSDL National Science Digital Library

Alveolar Gas is a computer program that lets you study some of the physiological factors that affect the composition of alveolar and expired gases. Such factors include dead space, tidal volume, the frequency of breathing, and the rates of oxygen consumption and carbon dioxide production. A worksheet is included.

1998-07-01

136

International Space Station Air Quality Assessed According to Toxicologically-Grouped Compounds  

NASA Technical Reports Server (NTRS)

Scores of compounds are found in the International Space Station (ISS) atmospheric samples that are returned to the Johnson Space Center Toxicology Laboratory for analysis. Spacecraft Maximum Allowable Concentrations (SMACs) are set with the view that each compound is present as if there were no other compounds present. In order to apply SMACs to the interpretation of the analytical data, the toxicologist must employ some method of combining the potential effects of the aggregate of compounds found in the atmospheric samples. The simplest approach is to assume that each quantifiable compound has the potential for some effect in proportion to the applicable SMAC, and then add all the proportions. This simple paradigm disregards the fact that most compounds have potential to adversely affect only a few physiological systems, and their effects would be independent rather than additive. An improved approach to dealing with exposure to mixtures is to add the proportions only for compounds that adversely affect the same physiological system. For example, toxicants that cause respiratory irritation are separated from those that cause neurotoxicity or cardio-toxicity. Herein we analyze ISS air quality data according to toxicological groups with a view that this could be used for understanding any crew symptoms occurring at the time of the sample acquisition. In addition, this approach could be useful in post-flight longitudinal surveys where the flight surgeon may need to identify post-flight, follow-up medical studies because of on-orbit exposures that target specific physiological systems.

James, John T.; Limero, Thomas F.; Beck, Steve; Cheng, Patti F.; deVera, Vanessa J.; Hand, Jennifer; Macatangay, Ariel

2010-01-01

137

International Space Station Air Quality Assessed According to Toxicologically-Grouped Compounds  

NASA Technical Reports Server (NTRS)

Scores of compounds are found in the International Space Station (ISS) atmospheric samples that are returned to the Johnson Space Center Toxicology Laboratory for analysis. Spacecraft Maximum Allowable Concentrations (SMACs) are set with the view that each compound is present as if there were no other compounds present. In order to apply SMACs to the interpretation of the analytical data, the toxicologist must employ some method of combining the potential effects of the aggregate of compounds found in the atmospheric samples. The simplest approach is to assume that each quantifiable compound has the potential for some effect in proportion to the applicable SMAC, and then add all the proportions. This simple paradigm disregards the fact that most compounds have potential to adversely affect only a few physiological systems, and their effects would be independent rather than additive. An improved approach to dealing with exposure to mixtures is to add the proportions only for compounds that adversely affect the same physiological system. For example, toxicants that cause respiratory irritation are separated from those that cause neurotoxicity or cardio-toxicity. Herein we analyze ISS air quality data according to toxicological groups with a view that this could be used for understanding any crew symptoms occurring at the time of the sample. In addition, this approach could be useful in post-flight longitudinal surveys where the flight surgeon may need to identify post-flight, follow-up medical studies because of on-orbit exposures that target specific physiological systems.

James, John T.; Limero, Tom; DeVera, Vanessa; Cheng, Patti; Hand, Jennifer; Macatangay, Ariel; Beck, Steve

2009-01-01

138

On the reflection type decomposition of the adjoint reduced phase space of a compact semisimple Lie group  

NASA Astrophysics Data System (ADS)

We consider a system with symmetries whose configuration space is a compact Lie group, acted upon by inner automorphisms. The classical reduced phase space of this system decomposes into connected components of orbit type subsets. To investigate hypothetical quantum effects of this decomposition one has to construct the associated costratification of the Hilbert space of the quantum system in the sense of Huebschmann. In the present paper, instead of the decomposition by orbit types, we consider the related decomposition by reflection types (conjugacy classes of reflection subgroups). These two decompositions turn out to coincide, e.g., for the classical groups SU(n) and Sp(n). We derive defining relations for reflection type subsets in terms of irreducible characters and discuss how to obtain from that the corresponding costratification of the Hilbert space of the system. To illustrate the method, we give explicit results for some low rank classical groups.

Hofmann, M.; Rudolph, G.; Schmidt, M.

2013-08-01

139

On the reflection type decomposition of the adjoint reduced phase space of a compact semisimple Lie group  

SciTech Connect

We consider a system with symmetries whose configuration space is a compact Lie group, acted upon by inner automorphisms. The classical reduced phase space of this system decomposes into connected components of orbit type subsets. To investigate hypothetical quantum effects of this decomposition one has to construct the associated costratification of the Hilbert space of the quantum system in the sense of Huebschmann. In the present paper, instead of the decomposition by orbit types, we consider the related decomposition by reflection types (conjugacy classes of reflection subgroups). These two decompositions turn out to coincide, e.g., for the classical groups SU(n) and Sp(n). We derive defining relations for reflection type subsets in terms of irreducible characters and discuss how to obtain from that the corresponding costratification of the Hilbert space of the system. To illustrate the method, we give explicit results for some low rank classical groups.

Hofmann, M. [Naturwissenschaftlich-Technische Fakultt, Universitt Siegen, Walter-Flex-Str. 3, 57068 Siegen (Germany)] [Naturwissenschaftlich-Technische Fakultt, Universitt Siegen, Walter-Flex-Str. 3, 57068 Siegen (Germany); Rudolph, G.; Schmidt, M. [Institut fr Theoretische Physik, Universitt Leipzig, Augustusplatz 10/11, 04109 Leipzig (Germany)] [Institut fr Theoretische Physik, Universitt Leipzig, Augustusplatz 10/11, 04109 Leipzig (Germany)

2013-08-15

140

[HOWTODO: INDEX & FIND SPACE GROUP FOR CITRIC ACID] February 23, 2010 o Down load CRYSFIRE, PowderCell and Citric zip files.  

E-print Network

[HOWTODO: INDEX & FIND SPACE GROUP FOR CITRIC ACID] February 23, 2010 o Down load CRYSFIRE the cd command) to the citric folder o #12;[HOWTODO: INDEX & FIND SPACE GROUP FOR CITRIC ACID & FIND SPACE GROUP FOR CITRIC ACID] February 23, 2010 o o Use the defaults for the next 7 queries

Meagher, Mary

141

Tangent spaces to motivic cohomology groups-on $CH^{\\bullet}(X,1)$ and $CH^{\\bullet}(X,2)$.  

E-print Network

Using higher K-theory and tensor triangular geometry, we propose K-theoretic higher Chow groups, at position 1 and 2, of derived categories of noetherian schemes and their Milnoe variants for regular schemes and infinitesimal thickenings. We discuss fuctoriality ans show that these new higher Chow groups agree with the classical ones for regular schemes. As an application, we define tangent spaces to these new higher Chow groups as usually and identify them with cohomology groups of absolute differentials. Moreover, combing our results with Green-Griffiths' work on tangent spaces to algebraic cycles, we put a geometric meaning to the tangent space to $CH^{2}(X,1)$, where X is a smooth projective surface over a field k, chark=0.

Sen Yang

142

Target selection and comparison of mission design for space debris removal by DLR's advanced study group  

NASA Astrophysics Data System (ADS)

Space debris is a growing problem. Models show that the Kessler syndrome, the exponential growth of debris due to collisions, has become unavoidable unless an active debris removal program is initiated. The debris population in LEO with inclination between 60 and 95 is considered as the most critical zone. In order to stabilize the debris population in orbit, especially in LEO, 5 to 10 objects will need to be removed every year. The unique circumstances of such a mission could require that several objects are removed with a single launch. This will require a mission to rendezvous with a multitude of objects orbiting on different altitudes, inclinations and planes. Removal models have assumed that the top priority targets will be removed first. However this will lead to a suboptimal mission design and increase the ?V-budget. Since there is a multitude of targets to choose from, the targets can be selected for an optimal mission design. In order to select a group of targets for a removal mission the orbital parameters and political constraints should also be taken into account. Within this paper a number of the target selection criteria are presented. The possible mission targets and their order of retrieval is dependent on the mission architecture. A comparison between several global mission architectures is given. Under consideration are 3 global missions of which a number of parameters are varied. The first mission launches multiple separate deorbit kits. The second launches a mother craft with deorbit kits. The third launches an orbital tug which pulls the debris in a lower orbit, after which a deorbit kit performs the final deorbit burn. A RoM mass and cost comparison is presented. The research described in this paper has been conducted as part of an active debris removal study by the Advanced Study Group (ASG). The ASG is an interdisciplinary student group working at the DLR, analyzing existing technologies and developing new ideas into preliminary concepts.

van der Pas, Niels; Lousada, Joao; Terhes, Claudia; Bernabeu, Marc; Bauer, Waldemar

2014-09-01

143

Space station needs, attributes and architectural options study commercialization working group briefing  

NASA Technical Reports Server (NTRS)

The benefits for each of the following commercial areas was investigated: communications, remote sensing, materials processing in space, low Earth orbit (LEO) satellite assembly, testing, and servicing, and space tourism. In each case, where economic benefits are derived, the costs for accomplishing tasks with the Space Station are compared with the cost with the Space Transportation System only.

1983-01-01

144

Transformation of Air Quality Monitor Data from the International Space Station into Toxicological Effect Groups  

NASA Technical Reports Server (NTRS)

The primary reason for monitoring air quality aboard the International Space Station (ISS) is to determine whether air pollutants have collectively reached a concentration where the crew could experience adverse health effects. These effects could be near-real-time (e.g. headache, respiratory irritation) or occur late in the mission or even years later (e.g. cancer, liver toxicity). Secondary purposes for monitoring include discovery that a potentially harmful compound has leaked into the atmosphere or that air revitalization system performance has diminished. Typical ISS atmospheric trace pollutants consist of alcohols, aldehydes, aromatic compounds, halo-carbons, siloxanes, and silanols. Rarely, sulfur-containing compounds and alkanes are found at trace levels. Spacecraft Maximum Allowable Concentrations (SMACs) have been set in cooperation with a subcommittee of the National Research Council Committee on Toxicology. For each compound and time of exposure, the limiting adverse effect(s) has been identified. By factoring the analytical data from the Air Quality Monitor (AQM), which is in use as a prototype instrument aboard the ISS, through the array of compounds and SMACs, the risk of 16 specific adverse effects can be estimated. Within each adverse-effect group, we have used an additive model proportioned to each applicable 180-day SMAC to estimate risk. In the recent past this conversion has been performed using archival data, which can be delayed for months after an air sample is taken because it must be returned to earth for analysis. But with the AQM gathering in situ data each week, NASA is in a position to follow toxic-effect groups and correlate these with any reported crew symptoms. The AQM data are supplemented with data from real-time CO2 instruments aboard the ISS and from archival measurements of formaldehyde, which the AQM cannot detect.

James, John T.; Zalesak, Selina M.

2011-01-01

145

THE ORIGIN OF OB CLUSTERS: FROM 10 pc TO 0.1 pc  

SciTech Connect

We observe the 1.2 mm continuum emission around the OB cluster-forming region G10.6-0.4, using the MAMBO-2 bolometer array of the IRAM 30 m telescope and the Submillimeter Array (SMA). Comparison of the Spitzer 24 {mu}m and 8 {mu}m images with our 1.2 mm continuum maps reveal an ionization front of an H II region, the photon-dominated layer, and several 5 pc scale filaments that follow the outer edge of the photon-dominated layer. The filaments, which are resolved in the MAMBO-2 observations, show regularly spaced parsec-scale molecular clumps, embedded with a cluster of dense molecular cores as shown in the SMA 0.87 mm observations. Toward the center of the G10.6-0.4 region, the combined SMA+IRAM 30 m continuum image reveals several parsec-scale protrusions. They may continue down to within 0.1 pc of the geometric center of a dense 3 pc scale structure, where a 200 M{sub Sun} OB cluster resides. The observed filaments may facilitate mass accretion onto the central cluster-forming region in the presence of strong radiative and mechanical stellar feedback. Their filamentary geometry may also facilitate fragmentation. We did not detect any significant polarized emission at 0.87 mm in the inner 1 pc region with SMA.

Liu Hauyu Baobab; Wang Ke; Ho, Paul T. P.; Zhang Qizhou [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Quintana-Lacaci, Guillermo [Instituto de Radioastronomia Milimetrica, Av. Divina Pastora 7, Nucleo Central, 18012 Granada (Spain); Li Zhiyun [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Zhang Zhiyu, E-mail: hlu@cfa.havard.edu, E-mail: kwang@cfa.harvard.edu, E-mail: qzhang@cfa.harvard.edu, E-mail: quintana@iram.es, E-mail: pho@asiaa.sinica.edu.tw, E-mail: zl4h@virginia.edu, E-mail: zzhang@mpifr.de [Max-Planck Institut fuer Radioastronomie, Auf dem Huegel 69, 53121, Bonn (Germany)

2012-01-20

146

LDEF meteoroid and debris special investigation group investigations and activities at the Johnson Space Center  

NASA Technical Reports Server (NTRS)

Since the return of the Long Duration Exposure Facility (LDEF) in January, 1990, members of the Meteoroid and Debris Special Investigation Group (M&D SIG) at the Johnson Space Center (JSC) in Houston, Texas have been examining LDEF hardware in an effort to expand the knowledge base regarding the low-Earth orbit (LEO) particulate environment. In addition to the various investigative activities, JSC is also the location of the general Meteoroid & Debris database. This publicly accessible database contains information obtained from the various M&D SIG investigations, as well as limited data obtained by individual LDEF Principal Investigators. LDEF exposed approximately 130 m(exp 2) of surface area to the LEO particulate environment, approximately 15.4 m(exp 2) of which was occupied by structural frame components (i.e., longerons and intercoastals) of the spacecraft. The data reported here was obtained as a result of detailed scans of LDEF intercoastals, 68 of which reside at JSC. The limited amount of data presently available on the A0178 thermal control blankets was reported last year and will not be reiterated here. The data presented here are limited to measurements of crater diameters and their frequency of occurrence (i.e., flux).

See, Thomas H.; Warren, Jack L.; Zolensky, Michael E.; Sapp, Clyde A.; Bernhard, Ronald P.; Dardano, Claire B.

1995-01-01

147

Hubble Space Telescope Snapshot Search for Planetary Nebulae in Globular Clusters of the Local Group  

E-print Network

Single stars in ancient globular clusters (GCs) are believed incapable of producing planetary nebulae (PNe), because their post-asymptotic-giant-branch evolutionary timescales are slower than the dissipation timescales for PNe. Nevertheless, four PNe are known in Galactic GCs. Their existence likely requires more exotic evolutionary channels, including stellar mergers and common-envelope binary interactions. I carried out a snapshot imaging search with the Hubble Space Telescope (HST) for PNe in bright Local Group GCs outside the Milky Way. I used a filter covering the 5007 A nebular emission line of [O III], and another one in the nearby continuum, to image 66 GCs. Inclusion of archival HST frames brought the total number of extragalactic GCs imaged at 5007 A to 75, whose total luminosity slightly exceeds that of the entire Galactic GC system. I found no convincing PNe in these clusters, aside from one PN in a young M31 cluster misclassified as a GC, and two PNe at such large angular separations from an M31 ...

Bond, Howard E

2015-01-01

148

Group Dynamics as a Critical Component of Successful Space Exploration: Conceptual Theory and Insights from the Biosphere 2 Closure Experiment  

NASA Astrophysics Data System (ADS)

As space exploration and eventually habitation achieves longer durations, successfully managing group dynamics of small, physically isolated groups will become vital. The paper summarizes important underlying research and conceptual theory and how these manifested in a well-documented example: the closure experiments of Biosphere 2. Key research breakthroughs in discerning the operation of small human groups comes from the pioneering work of W.R. Bion. He discovered two competing modalities of behavior. The first is the task-oriented or work group governed by shared acceptance of goals, reality-thinking in relation to time, resources and rational, and intelligent management of challenges presented. The opposing, usually unconscious, modality is what Bion called the basic-assumption group and alternates between three group animal groups: dependency/kill the leader; fight/flight and pairing. If not dealt with, these dynamics work to undermine and defeat the conscious task groups goal achievement. The paper discusses crew training and selection, various approaches to structuring the work and hierarchy of the group, the importance of contact with a larger population through electronic communication and dealing with the us-them syndrome frequently observed between crew and Mission Control. The experience of the first two year closure of Biosphere 2 is drawn on in new ways to illustrate vicissitudes and management of group dynamics especially as both the inside team of biospherians and key members of Mission Control had training in working with group dynamics. Insights from that experience may help mission planning so that future groups in space cope successfully with inherent group dynamics challenges that arise.

Nelson, Mark; Allen, John P.

149

Conformal group and fundamental theorem for a class of symmetric * *spaces 1  

E-print Network

such spaces, called symmetric spaces with twist, are equi* *valent to Jordan triple systems (JTS), and we canonically associate* * a chart, called Jordan coordinates, such that Ep is represented by the usual

Bertram, Wolfgang - Institut de Mathématiques ?lie Cartan, Université Henri Poincaré

150

The q-analog of the boson algebra, its representation on the Fock space, and applications to the quantum group  

NASA Astrophysics Data System (ADS)

In this paper, a realization of the q-deformed boson operators on the Fock space from a generally algebraic point of view is given. The representations of the quantum group (Cn)q are thereby constructed in terms of this realization. Some infinite- and finite-dimensional representations of the q-analog of the Heisenberg-Weyl algebra are obtained on certain quotient spaces. Finally, the q-deformed differential realization of quantum group given by Alvarez-Gaume, Gomez, and Sierra (Preprint CERN-Th 5369/89) is derived from the boson realization.

Sun, Chang-Pu; Ge, Mo-Lin

1991-03-01

151

Creating Social Spaces to Tackle AIDS-Related Stigma: Reviewing the Role of Church Groups in Sub-Saharan Africa  

Microsoft Academic Search

An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people\\u000a living with AIDS and challenging or contributing to HIV\\/AIDS-related stigma. Treating church groups as social spaces in which\\u000a HIV\\/AIDS-related stigma may potentially be challenged, we systematically review this literature, identifying five themes that\\u000a highlight the complex and contradictory role of

C. Campbell; M. Skovdal; A. Gibbs

2011-01-01

152

Group space allowance has little effect on sow health, productivity, or welfare in a free-access stall system.  

PubMed

Free-access stalls allow sows to choose the protection of a stall or use of a shared group space. This study investigated the effect of group space width, 0.91 (SS), 2.13 (IS), and 3.05 (LS) m, on the health, production, behavior, and welfare of gestating sows. Nine replications of 21 (N = 189) gestating sows were used. At gestational d 35.4 2.3, the pregnant sows were distributed into 3 pens of 7 sows, where they remained until 104.6 3.5 d. Each treatment pen had 7 free-access stalls and a group space that together provided 1.93 (SS), 2.68 (IS), or 3.24 (LS) m(2)/sow. Baseline measurements were obtained before mixing. Back fat depth, BW, BCS, and lameness were measured monthly, and skin lesions were scored weekly. Blood was collected monthly for hematological, immunological, and cortisol analyses. Sow behavior was video recorded continuously during the initial 4 d of treatment and 24 h every other week thereafter. Behavior was analyzed for location, posture, pen investigation, social contact, and aggression. Skin response to the mitogen concanavalin A (Con A) was tested at mean gestational d 106. Litter characteristics including size and weight were collected at birth and weaning. The data were analyzed using a mixed model. Multiple comparisons were adjusted with the Tukey-Kramer and Bejamini-Hochberg methods. Group space allowance had no effect on any measure of sow health, physiology, or production (P ? 0.10). Sows in the SS, IS, and LS pens spent 77.88% 3.88%, 66.02% 3.87%, and 63.64% 3.91%, respectively, of their time in the free-access stalls (P = 0.12). However, SS sows used the group space less than IS and LS sows (P = 0.01). Overall, pen investigatory behavior was not affected by group space allowance (P = 0.91). Sows in the LS pens spent more time in a social group than SS sows (P = 0.02), whereas sows in IS pens were intermediate to, but not different from, the other treatments (P ? 0.10). The size of the social groups was also affected by the group space allowance (P = 0.03), with SS sows forming smaller groups than LS sows; again, IS sows were intermediate to, but not different from, the other treatments. Although the group space allowance had no measurable impact on the health, physiology, or productivity of the sows, the lower group space use and social contact of the SS sows reduced the behavioral diversity benefits of group housing and may indicate an avoidance of social stressors or a lack of physical comfort in the smallest pens. PMID:24668955

Mack, L A; Lay, D C; Eicher, S D; Johnson, A K; Richert, B T; Pajor, E A

2014-06-01

153

Ultraviolet-Optical Space Astronomy Beyond HST Conference (Origins Conference and UV-Optical Working Group Support)  

NASA Technical Reports Server (NTRS)

This grant supported three major activities, from 1997-2001. (1) Origins Conference. The funds from this grant were used, initially, to support a Conference on "Origins", held May 19-23, 1997 at Estes Park, CO and attended by a wide range of astronomers, planetary scientists, and astrobiologists. The scientific proceedings of this meeting were published in 1998 by the Astronomical Society of the Pacific: "Origins" (1998) "Proceedings of the International Origins Conference". (2) UV-Optical Space Astronomy. Conference Additional funds provided by the NASA Office of Space Science were used to support a meeting held August 5-7, 1998 at Boulder, CO and attended by ultraviolet and optical astronomers and instrumentalists interested in a UV-O successor to the Hubble Space Telescope. The scientific proceedings of this meeting were published in 1999: "Ultraviolet-Optical Space Astronomy Beyond the Hubble Space Telescope" (1999), NASA provided funds and commissioned the UVOWG (Ultraviolet-Optical Working Group), charged with recommending a set of fundamental scientific problems and new space missions in the UV/Optical wavelength bands. The working group was chaired by J. M. Shull, and included ten other astrophysicists. Their report was published as a "White Paper" (Nov. 1999) entitled "The Emergence of the Modern Universe: Tracing the Cosmic Web" available. The results of this report were used in the NASA Strategic Planning ("Roadmap") exercise and by the NRC Astronomy/Astrophysics Decade Committee.

Shull, J. Michael; Morse, Jon

2001-01-01

154

Proceedings of the Space Shuttle Sortie Workshop. Volume 2: Working group reports  

NASA Technical Reports Server (NTRS)

Details are presented on the mission planning progress in each of the working paper reports. The general topics covered are the following: space technology; materials processing and space manufacturing; communications and navigation; earth and ocean physics; oceanography; earth resources and surface environmental quality; meteorology and atmospheric environmental quality; life sciences; atmospheric and space physics; solar physics; high energy cosmic rays; X-ray and gamma ray astronomy; ultraviolet-optical astronomy; planetary astronomy; and infrared astronomy.

1972-01-01

155

Differentiation of PC12 Cells  

NSDL National Science Digital Library

This 3-week-long series of collaborative laboratory exercises explores how to use a cultured cell system (PC12 cells) to study signaling pathways involved in cellular differentiation. The laboratory would be useful in a neurobiology or cell biology course for advanced undergraduate students. The background and details for performing the lab are provided along with suggestions for assessing student performance and understanding.

Elizabeth M. Adler (American Association for the Advancement of Science; Associate Editor of Science's STKE REV)

2006-09-05

156

D2PC sensitivity analysis  

SciTech Connect

The Chemical Hazard Prediction Model (D2PC) developed by the US Army will play a critical role in the Chemical Stockpile Emergency Preparedness Program by predicting chemical agent transport and dispersion through the atmosphere after an accidental release. To aid in the analysis of the output calculated by D2PC, this sensitivity analysis was conducted to provide information on model response to a variety of input parameters. The sensitivity analysis focused on six accidental release scenarios involving chemical agents VX, GB, and HD (sulfur mustard). Two categories, corresponding to conservative most likely and worst case meteorological conditions, provided the reference for standard input values. D2PC displayed a wide variety of sensitivity to the various input parameters. The model displayed the greatest overall sensitivity to wind speed, mixing height, and breathing rate. For other input parameters, sensitivity was mixed but generally lower. Sensitivity varied not only with parameter, but also over the range of values input for a single parameter. This information on model response can provide useful data for interpreting D2PC output.

Lombardi, D.P.

1992-08-01

157

A summary of activities of the US/Soviet-Russian joint working group on space biology and medicine  

NASA Astrophysics Data System (ADS)

The very foundation of cooperation between the United States (US) and Russia (former Soviet Union) in space exploration is a direct result of the mutual desire for scientific understanding and the creation of a collaborative mechanismthe Joint Working Group (JWG) on Space Biology and Medicine. From the dawn of the space age, it has been the quest of humankind to understand its place in the universe. While nations can and do solve problems independently, it takes nations, working together, to accomplish great things. The formation of the JWG provided an opportunity for the opening of a series of productive relationships between the superpowers, the US and the Union of Soviet Socialist Republics (USSR); and served as a justification for continued relationship for medical assistance in spaceflight, and to showcase Earth benefits from space medicine research. This relationship has been played out on an international scale with the construction and operation of the International Space Station. The fundamental reason for this successful endeavor is a direct result of the spirit and perseverance of the men and women who have worked diligently side-by-side to promote science and move our understanding of space forward. This manuscript provides a historical perspective of the JWG; how it came about; its evolution; what it accomplished; and what impact it has had and continues to have in the 21st century with regard to human spaceflight and space life sciences research. It captures the spirit of this group, which has been in continuous existence for over 40 years, and provides a never before reported summary of its activities.

Doarn, Charles R.; Nicogossian, Arnauld E.; Grigoriev, Anatoly I.; Tverskaya, Galina; Orlov, Oleg I.; Ilyin, Eugene A.; Souza, Kenneth A.

2010-10-01

158

Astronaut Jeffrey Hoffman works with replacement WF/PC II for HST  

NASA Technical Reports Server (NTRS)

Anchored to the Space Shuttle Endeavour's Remote Manipulator System (RMS) arm, Astronaut Jeffrey A. Hoffman works with the replacement Wide Field/Planetary Camera (WF/PC II) for the Hubble Space Telescope (HST) during the third of five space walks. Astronaut F. Story Musgrave, who joined Hoffman for three of the five space walks, helps with alignment at center frame.

1993-01-01

159

The Origin of OB Clusters: From 10 pc to 0.1 pc  

E-print Network

We observe the 1.2 mm continuum emission around the OB cluster forming region G10.6-0.4, using the IRAM 30m telescope MAMBO-2 bolometer array and the Submillimeter array. Comparison of the Spitzer 24 $\\mu$m and 8 $\\mu$m images with our 1.2 mm continuum maps reveals the ionization front of an HII region, the photon-dominated layer, and several 5 pc scale filaments following the outer edge of the photon-dominated layer. The filaments, which are resolved in the MAMBO-2 observations, show regularly spaced parsec-scale molecular clumps, embedded with a cluster of submillimeter molecular cores as shown in the SMA 0.87 mm observations. Toward the center of the G10.6-0.4 region, the combined SMA+IRAM 30m continuum image reveals several, parsec-scale protrusions. They may continue down to within 0.1 pc of the geometric center of a dense 3 pc size structure, where a 200 M$_{\\odot}$ OB cluster resides. The observed filaments may facilitate mass accretion onto the central cluster--forming region in the presence of strong...

Liu, Hauyu Baobab; Wang, Ke; Ho, Paul T P; Li, Zhi-Yun; Zhang, Qizhou; Zhang, Zhiyu

2011-01-01

160

Comparison of Polar Cap (PC) index calculations.  

NASA Astrophysics Data System (ADS)

The Polar Cap (PC) index introduced by Troshichev and Andrezen (1985) is derived from polar magnetic variations and is mainly a measure of the intensity of the transpolar ionospheric currents. These currents relate to the polar cap antisunward ionospheric plasma convection driven by the dawn-dusk electric field, which in turn is generated by the interaction of the solar wind with the Earth's magnetosphere. Coefficients to calculate PCN and PCS index values from polar magnetic variations recorded at Thule and Vostok, respectively, have been derived by several different procedures in the past. The first published set of coefficients for Thule was derived by Vennerstrm, 1991 and is still in use for calculations of PCN index values by DTU Space. Errors in the program used to calculate index values were corrected in 1999 and again in 2001. In 2005 DMI adopted a unified procedure proposed by Troshichev for calculations of the PCN index. Thus there exists 4 different series of PCN index values. Similarly, at AARI three different sets of coefficients have been used to calculate PCS indices in the past. The presentation discusses the principal differences between the various PC index procedures and provides comparisons between index values derived from the same magnetic data sets using the different procedures. Examples from published papers are examined to illustrate the differences.

Stauning, P.

2012-04-01

161

Group dynamics in a long-term blind endeavor on Earth: An analog for space missions (Lewis & Clark Expedition group dynamic analysis)  

NASA Astrophysics Data System (ADS)

In 1803, President Thomas Jefferson set fourth a military expedition led by Captains M. Lewis and W. Clark (Lewis and Clark Expedition) on an exploration that would become an everlasting part of US national history and pride. Looking back at the events of this exploration, there are many similarities to the experiences future human space explorers will face as we look to colonize the Moon and travel to Mars and beyond (NASA Vision for Space Exploration, 2004): The Lewis and Clark Expedition lasted almost three years and involved a crew of 43 men traveling up the Missouri River to explore the unknown lands and a possible water route to the Pacific Ocean; The Expedition took place far away from customary comfortable environments known to European settlers in the early 18th century; The Expedition involved a remotely confined high-perceived risk environment with high levels of uncertainty providing stresses and every day challenges for the crew; Supplies brought on the mission were limited (mainly a mass/weight issue rather than cost), therefore the discovery and use of environmental resources (In-Situ Resource Utilization approach, including info-resources to mitigate uncertainty) was necessary for crew survival. The environments astronauts will encounter in space and on the Moon and Mars due to high risk and uncertainty will be in many aspects similar to what Lewis and Clark's crew experienced, as environments will be hostile and unforgiving if problems arise and aren't resolved quickly. The analysis provided in this research paper is relevant because the Lewis and Clark Expedition needed to move extensively and with minimal supplies. Polar remote settings, which were analyzed extensively, were different from this expedition due to the fact that these missions did not encompass extensive movement of crew facilities and supplies and were more like space missions orbiting the Earth. Using past space station results of performance on orbit in correlation with a suggested distinguishable mission phase model, the Lewis and Clark Expedition will be analyzed for similarities to these space findings. Factors of consideration in support of this analysis involve an understanding of the leadership qualities of Lewis and Clark (and relations established and maintained with one another), the selection and diversity of their crew, and the group dynamics that were developed and maintained so carefully during the expedition. With this knowledge and understanding one can gain enormous insights useful in the planning and preparation for future long-duration space exploratory missions with high level of autonomy, mobility, minimal primary life support supply and high dependence on material re-circulation and In-Situ Resource Utilization approach.

Allner, M.; Rygalov, V.

2008-12-01

162

Iterative Spatial Sequence Estimator for Multi-Group Space Time Trellis Coded Systems  

E-print Network

-Ghadhban, Maruf Mohammad, and B. Woerner Mobile and Portable Radio Research Group Virginia Tech E-Mail: {maruf with soft-input soft- output (SISO) maximum a posteriori (MAP) algorithm as the detection stage in the multi-group receiver. It will iterate and share soft information with the soft decoding stage. The remainder

Al-Ghadhban, Samir

163

Space station needs attributes and architectural options study costing working group briefing  

NASA Technical Reports Server (NTRS)

Individuals in the United States who understand the promise of materials processing in space and who also are senior technical personnel associated with commercial firms that process materials: (1) endorsed the concept of a space station as a desirable national asset; (2) stated that a commercial MPS research program is mandatory to extend commericalization of space for materials processing; and (3) described in general terms a national research laboratory and free flying facilities that are needed. Participants agreed that industry R&D is motivated largely by market pull rather than by technology push, that initial interest is low-g materials research; and that to farther, commercial market assurance (a salable product) is a must.

1983-01-01

164

Crystallization and preliminary X-ray analysis of thiaminase I from Bacillus thiaminolyticus: space group change upon freezing of crystals.  

PubMed

Thiaminase I (Mr = 42 100) from B. thiaminolyticus, expressed in E. coli, has been crystallized by the vapor-diffusion method. Three crystal forms, two of which grew from 0.1 M sodium acetate (pH = 4.6), 0.2 M ammonium sulfate and 30%(w/v) PEG 2000, have been examined by X-ray analysis. One crystal form diffracted to 2.5 A at room temperature, was orthorhombic, and had unit-cell edges of a = 87.7, b = 120.5 and c = 76.7 A with space group P212121. A self-Patterson map showed a strong peak indicating noncrystallographic translational pseudosymmetry with (u, v, w) = (0.03, 0.0, 0.5). When these crystals were frozen at liquid-nitrogen temperatures, a second crystal form was observed which had unit-cell dimensions a = 85.5, b = 117.5 and c = 36.6 A with space group P21212. A third crystal form grew from 0.1 M Tris (pH = 8.5), 0.2 M sodium acetate trihydrate and 28%(w/v) PEG 6000 to produce orthorhombic crystals of space group P212121 with cell edges of a = 114.4, b = 123.1 and c = 92.5 A. PMID:9761925

Campobasso, N; Begun, J; Costello, C A; Begley, T P; Ealick, S E

1998-05-01

165

Creating Social Spaces to Tackle AIDS-Related Stigma: Reviewing the Role of Church Groups in Sub-Saharan Africa  

PubMed Central

An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people living with AIDS and challenging or contributing to HIV/AIDS-related stigma. Treating church groups as social spaces in which HIV/AIDS-related stigma may potentially be challenged, we systematically review this literature, identifying five themes that highlight the complex and contradictory role of the church as a potential agent of health-enhancing social change. In many ways the church perpetuates HIV/AIDS-related stigma through (i) moralistic attitudes and (ii) its reinforcement of conservative gender ideologies. However some churches have managed move towards action that makes a more positive contribution to HIV/AIDS management through (iii) promoting various forms of social control for HIV prevention, (iv) contributing to the care and support of the AIDS-affected and (v) providing social spaces for challenging stigmatising ideas and practices. We conclude that church groups, including church leadership, can play a key role in facilitating or hindering the creation of supportive social spaces to challenge stigma. Much work remains to be done in developing deeper understandings of the multi-layered factors that enable some churches, but not others, to respond effectively to HIV/AIDS. PMID:20668927

Skovdal, M.; Gibbs, A.

2012-01-01

166

Evaluating a Safe Space Training for School Counselors and Trainees Using a Randomized Control Group Design  

ERIC Educational Resources Information Center

School counselors need to advocate and act as an ally for all students. Safe Space, a training designed to facilitate competency for working with and serving LGBTQ youth (i.e., LGBTQ competency), has received increased attention in the field of school counseling. However, limited empirical support exists for training interventions such as Safe

Byrd, Rebekah; Hays, Danica G.

2014-01-01

167

Determination of the orbit spaces of non-coregular compact linear groups with one relation among the basic polynomial invariants in the $\\\\hat P$-matrix approach  

Microsoft Academic Search

Invariant functions under the transformations of a compact linear group $G$ acting in $\\\\real^n$ can be expressed in terms of functions defined in the orbit space of $G$. We develop a method to determine the isotropy classes of the orbit spaces of all the real linear groups whose integrity bases (IB) satisfy only one independent relation. The method is tested

G. Sartori; G. Valente

2000-01-01

168

Unsteady Reynolds averaged Navier-Stokes simulation of the post-critical flow around a closely spaced group of silos  

NASA Astrophysics Data System (ADS)

During a storm in October 2002, wind induced ovalling vibrations were observed on several empty silos of a closely spaced group (pitch-to-diameter ratio of 1.05) consisting of 8 by 5 silos in the port of Antwerp (Belgium). Numerical simulations of the turbulent wind flow are performed to clarify the occurrence of the observed ovalling vibrations near the lee side corner of the group by studying the dynamic wind pressures on the silo surfaces and linking to the dynamic properties of the silo structures. As the orientation of the group largely affects the pressure distribution around the cylinders of the group, the influence of the angle of incidence of the wind flow on these ovalling vibrations is examined while other parameters, such as spacing ratio and Reynolds number are unchanged. To achieve results within a reasonable computation time, 2D unsteady Reynolds averaged Navier-Stokes (URANS) equations using Menter's shear stress transport turbulence model were performed. In order to elucidate the influence of the applied turbulence model and to qualitatively validate the spatial and temporal discretization of the 2D highly turbulent post-critical (Re=1.24107) flow simulations for the silo group, single cylinder simulations were used. The geometric resemblance of the group arrangement with rectangular cylinders on the one hand and of the interstitial spaces with tube arrays (e.g. heat exchangers) on the other hand is used to qualitatively compare the observed flow phenomena. The simulations show that the silo group can be treated neither as a tube array nor as a solid bluff body. Subsequent linking of dynamic wind pressures to dynamic properties of the silo structures reveals strong narrow band frequency peaks in the turbulent pressure coefficient spectra of the silos near the lee side corners of the group that match the structural natural frequencies of the third and fourth ovalling mode shape of the silos. This match indicates a forced, resonant response which corresponds with the observed pattern of ovalling vibrations with three and four circumferential wavelengths. While the precise physical excitation mechanism is not yet fully understood, the simulations exclude discrete vortex shedding and since fluidelastic instability could not be considered, only turbulent buffeting remains which could very well give rise to the narrow band wake phenomena causing the ovalling silo wall vibrations.

Hillewaere, J.; Dooms, D.; Van Quekelberghe, B.; Degroote, J.; Vierendeels, J.; De Roeck, G.; Lombaert, G.; Degrande, G.

2012-04-01

169

Decomposable representations and Lagrangian submanifolds of moduli spaces associated to surface groups  

Microsoft Academic Search

The importance of explicit examples of Lagrangian submanifolds of moduli spaces is revealed by papers such as Dostoglou and\\u000a Salamon (Ann. of Math (2), 139(3), 581640, 1994) and Salamon (Proceedings of the international congress of mathematicians,\\u000a vol.1, 2 (Zrich, 1994), pp. 526536. Birkhuser, Basel, 1995): given a 3-manifold M with boundary ?M= ?, Dostoglou and Salamon use such examples to

Florent Schaffhauser

2008-01-01

170

The group approach to AdS space propagators: a fast algorithm  

Microsoft Academic Search

In this paper we show how the method of [4] for the calculation of two-point functions in (d + 1)-dimensional AdS space can be simplified. This results in an algorithm for the evaluation of the two-point functions as linear combinations of Legendre functions of the second kind. This algorithm can be easily implemented on a computer. For the sake of

Thorsten Leonhardt; Werner Rhl; Ruben Manvelyan

2004-01-01

171

The redshift-space neighborhoods of 36 loose groups. 2: Analysis  

NASA Technical Reports Server (NTRS)

We explore the kinematics of 36 rich RGH89 groups identified from the first two complete slices of the CfA redshift survey. These groups have more than five members identified by a friends-of-friends algorithm at a number density contrast delta rho/rho greater than or equal to 80. To examine the stability of the determination of the velocity dispersion for these systems, we compare results for the original 232 members with results for a larger redshift sample, including 334 fainter members in the redshift neighborhoods. On average, we double the number of group members in each system. The observed distribution of velocity dispersions is stable. In fact, the velocity dispersion based on the original members identified in the CfA redshift survey is a reliable predictor of the value for the enlarged sample in an individual group. The velocity dispersion is thus a stable physical parameter for discrimination among systems galaxies. A larger sample of groups, particularly one selected from a distance limited catalog, should provide an interesting constraint on models for the formation of large-scale structure. We take H(sub 0) = km/s/Mpc.

Ramella, Massimo; Geller, Margaret J.; Hurchra, John P.; Thorstensen, John R.

1995-01-01

172

Job Scheduling with Lookahead Group Matchmaking for Time/Space Sharing on Multi-core Parallel Machines  

NASA Astrophysics Data System (ADS)

Multi-core nodes of parallel machines may only provide gradual performance improvement per application due to competition on resources like the cache. As shown in our earlier work, spreading out applications over as many nodes as possible or letting different applications with potentially complementary characteristics (semi time) share each node by allocating different cores to them may provide better performance. In the latter case, groups of jobs may be necessary to obtain balanced resource utilization due to different sizes of jobs. We present a scheduler G-LOMARC-TS which can match groups of jobs and consider both space- and time-sharing allocation. Since matchmaking may select jobs further down in the waiting queue, fairness in regards to possible delays of the other jobs is watched and delays are kept within certain bounds. This results in a large number of possible combinations. A number of heuristics to select the most promising combinations make it possible to deal with the NP-completeness of the problem. We show that our scheduler improves utilization of high-load phases by about 27% and subsequently average response times by about 36% (and 53% for long jobs) compared to space sharing scheduling for normal workloads. Additionally the scheduler can handle much higher workloads than a space-sharing scheduler.

Zeng, Xijie; Sodan, Angela C.

173

Astronaut Jeffrey Hoffman with WF/PC during third STS-61 EVA  

NASA Technical Reports Server (NTRS)

Astronaut Jeffrey A. Hoffman, anchored on the end of the Remote Manipulator System (RMS) arm, is pictured with the Wide Field/Planetary Camera (WF/PC I) during the third of the five STS-61 space walks. Astronaut F. Story Musgrave, stationed at the stowage area at bottom of frame, assists. WF/PC II is in place on the Hubble Space Telescope (HST).

1993-01-01

174

Creating Spaces for Critical Transformative Dialogues: Legitimising Discussion Groups as Professional Practice  

ERIC Educational Resources Information Center

Focussed dialogue (as lived and living practices) can have a powerful role in renewing professional practice, advancing its sustainability and development as administrative and political systems colonise the practices of teachers and teacher educators. However, participating in discussion groups for many teachers, including those in academia, is

Edwards-Groves, Christine J.

2013-01-01

175

The Uncertainty Principle: Group Theoretic Approach, Possible Minimizers and Scale-Space Properties  

Microsoft Academic Search

The uncertainty principle is a fundamental concept in the context of signal and image processing, just as much as it has been in the framework of physics and more recently in harmonic analysis. Uncertainty principles can be derived by using a group theoretic approach. This approach yields also a formalism for finding functions which are the minimizers of the uncertainty

Chen Sagiv; Nir A. Sochen; Yehoshua Y. Zeevi

2006-01-01

176

Two-Dimensional Space-Time Dependent Multi-group Diffusion Equation with SLOR Method  

SciTech Connect

The research of two-dimensional space-time diffusion equations with SLOR (Successive-Line Over Relaxation) has been done. SLOR method is chosen because this method is one of iterative methods that does not required to defined whole element matrix. The research is divided in two cases, homogeneous case and heterogeneous case. Homogeneous case has been inserted by step reactivity. Heterogeneous case has been inserted by step reactivity and ramp reactivity. In general, the results of simulations are agreement, even in some points there are differences.

Yulianti, Y. [Physics Department, University of Lampung (UNILA), Jl. Sumantri Brojonegoro No. 1 Bandar Lampung (Indonesia); Su'ud, Z.; Waris, A.; Khotimah, S. N. [Physics Department, Bandung Institute of Technology (ITB), Jl. Ganesha 10 Bandung (Indonesia)

2010-06-22

177

The group approach to AdS space propagators: A fast algorithm  

E-print Network

In this letter we show how the method of [4] for the calculation of two-point functions in d+1-dimensional AdS space can be simplified. This results in an algorithm for the evaluation of the two-point functions as linear combinations of Legendre functions of the second kind. This algorithm can be easily implemented on a computer. For the sake of illustration, we displayed the results for the case of symmetric traceless tensor fields with rank up to l=4.

Thorsten Leonhardt; Ruben Manvelyan; Werner Ruhl

2003-10-07

178

75 FR 62002 - Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350...  

Federal Register 2010, 2011, 2012, 2013

...in the Airworthiness Limitations Section (ALS). For PC-6 models other than B2-H2 and B2- H4, no ALS at all is included in the AMM. With the latest...models other than B2-H2 and B2-H4, a new ALS document has been implemented as well....

2010-10-07

179

76 FR 5467 - Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350...  

Federal Register 2010, 2011, 2012, 2013

...in the Airworthiness Limitations Section (ALS). For PC-6 models other than B2-H2 and B2- H4, no ALS at all is included in the AMM. With the latest...models other than B2-H2 and B2-H4, a new ALS document has been implemented as well....

2011-02-01

180

SUSY `99 P.C. Bhat June 14-19, 1999 Prospects for  

E-print Network

Accelerator Laboratory for The Fermilab Run 2 Higgs Working Group #12;SUSY `99 P.C. Bhat June 14-19, 1999 60 70 80 90 100 SHW b tagging efficiency: Alternative tight / loose scheme: #12;SUSY `99 P.C. Bhat

Bhat, Pushpalatha

181

Space  

NSDL National Science Digital Library

This unit begins by introducing students to the historical motivation for space exploration. They learn about the International Space Station, including current and futuristic ideas that engineers are designing to propel space research. Then they learn about the physical properties of the Moon, and think about what types of products engineers would need to design in order for humans to live on the Moon. Lastly, students learn some descriptive facts about asteroids, such as their sizes and how that relates to the potential danger of an asteroid colliding with the Earth.

Integrated Teaching And Learning Program

182

Individual and grouping track pits etched in the exposed in a free space plastic track detectors  

NASA Astrophysics Data System (ADS)

New results concerned to the investigation of depth-dependent the pit-like surface-average and the grouping track-density distributions in the cosmic ray exposed column of CN-85 and CR-39 plastic solid state nuclear track detectors (SSNTD) are presented. Two main sources: solar cosmic ray protons and recoil nuclei for very short (length <3 ?m) track-pit formation are considered. Theoretical estimation of the total, uniform track-pit density indicates on failure of evidence of some additional radiation effects, partially, hypothetically conditioned with the Erzion theory. Some quantitative proofs of this hypothesis have been obtained in the measurements of the pit-groups. Totally, up to this time it was registered near of 30 pit groups with the surface pit-density in the interval of (1-15) 106 cm2, that is two-three orders of magnitude higher than uniformly distributed track-pits on the same CR-39 plate surface. As a result of layer-by-layer investigation of the exposed CN-85 stock arrangement three pit swarms exactly correlated with the end point of high ionizing primary charge particle tracks were observed. Obtained data are considered in according to submission based on the probability of detection for the negative charged cosmic ray Erzion particles stopping events.

Kashkarov, L.; Bazhutov, Yu

2013-02-01

183

Polar space group and complex magnetism in Ni11?(HPO3)8(OH)6: towards a new multiferroic material?  

NASA Astrophysics Data System (ADS)

The Ni11?(HPO3)8(OH)6 phosphite was prepared using a hydrothermal method. Depending on the pressure used during the synthesis, different hierarchical superstructures were encountered, including a new original cross-shaped star. The as-obtained products were characterized by X-ray diffraction, scanning and transmission electron microscopy and magnetization. In agreement with the presence of transition metal dimers in the structure, a complex magnetic behavior is observed at low temperature. This magnetic ground-state, combined with the non-centrosymmetry of the space group, creates new opportunities for applications in this class of open framework inorganic materials.

Poienar, M.; Maignan, A.; Sfirloaga, P.; Malo, S.; Vlazan, P.; Guesdon, A.; Lain, F.; Rouquette, J.; Martin, C.

2015-01-01

184

Between-group behaviour in health care: gaps, edges, boundaries, disconnections, weak ties, spaces and holes. A systematic review  

PubMed Central

Background Gaps are typically regarded as a problem to be solved. People are stimulated to close or plug them. Researchers are moved to fill deficits in the literature in order to realise a more complete knowledge base, health authorities want to bridge policy-practice disconnections, managers to secure resources to remedy shortfalls between poor and idealised care, and clinicians to provide services to patients across the divides of organisational silos. Despite practical and policy work in many health systems to bridge gaps, it is valuable to study research examining them for the insights provided. Structural holes, spaces between social clusters and weak or absent ties represent fissures in networks, located in less densely populated parts of otherwise closely connected social structures. Such gaps are useful as they illustrate how communication potentially breaks down or interactivity fails. This paper discusses empirical and theoretical work on this phenomenon with the aim of analysing a specific exemplar, the structures of silos within health care organisations. Methods The research literature on social spaces, holes, gaps, boundaries and edges was searched systematically, and separated into health [n = 13] and non-health [n = 55] samples. The health literature was reviewed and synthesised in order to understand the circumstances between stakeholders and stakeholder groups that both provide threats to networked interactions and opportunities to strengthen the fabric of organisational and institutional inter-relationships. Results The research examples illuminate various network structure characteristics and group interactions. They explicate a range of opportunities for improved social and professional relations that understanding structural holes, social spaces and absent ties affords. A principal finding is that these kinds of gaps illustrate the conditions under which connections are strained or have been severed, where the limits of integration between groups occurs, the circumstances in which social spaces are or need to be negotiated and the way divides are bridged. The study's limitations are that it is bounded by the focus of attention and the search terms used and there is yet to be developed a probabilistic, predictive model for gaps and how to connect them. Conclusions Gaps offer insights into social structures, and how real world behaviours of participants in workplaces, organisations and institutions are fragile. The paper highlights the circumstances in which network disjunctures and group divides manifest. Knowledge of these phenomenon provides opportunities for working out ways to improve health sector organisational communications, knowledge transmission and relationships. PMID:21134295

2010-01-01

185

Group dynamics during the EXEMSI isolation study. Experimental Campaign for the European Manned Space Infrastructure.  

PubMed

The objectives of this study were to investigate the social behavior, interrelations, cohesion, efficiency and team formation of the crew during 60 days of isolation and confinement, to make a critical comparison of a variety of test methods used for this purpose and to formulate recommendations for their applications in selection, training and support for future studies of this kind. The study consisted of three phases: (1) the pre-isolation period, in which initial individual and group assessment were made to understand the motivation, characteristics, and styles of the crew members, the state of the crew, and to make a prognosis for the behavior of the group and its members, (2) the isolation period, with tests and observations to follow and analyze behavior and group dynamics of the crew, and to detect manifestations of stress, and (3) the post-isolation period with final assessment and debriefing. During these three periods individual and group tests were carried out. Direct methods, questionnaires and tests, as well as indirect methods, observations of behavior, were used. These had cognitive, affective-emotional and social components; they were quantitative, qualitative or a combination. Before isolation the crew members expressed strong confidence in the team and in their own personal capability. The leadership of the Commander seemed uncontested. Crew functioning during this period was conflict-free, but was structured in a rather rigid and defensive way (isolation of affects, denial of anxiety). Apparently, the members strongly needed to present a good image image of themselves. The relatively short period of the experiment, and the absence of real risk suggested that the crew would be able to maintain their cohesion, but in a real spaceflight situation this behavior could be inadequate and even dangerous. The pre-isolation prognosis for crew behavior during isolation was validated to a large extent. During isolation there were no clear manifestations of stress. Nevertheless, the confinement and isolation were experienced as the major stress factors. The crew members described themselves as a heterogeneous but harmonious group that was successful in their mission. In fact, the team maintained its cohesion by opposing external authority, using management as a scapegoat. Occasionally, in times of crisis, they also criticized ground crew. The Commander supported this attitude. Strongly differences in personality and behavior were noted. Analysis of the sociometric data showed that the asserted harmony was more apparent than real. It is questionable whether the group cohesion would have persisted in a life threatening crisis or even in a prolongation of the experiment. The most reliable instruments for this type of survey seem to be: group methods, non-obstructive tests, indirect instruments, and qualitative tools. The least reliable are: strictly quantitative methods, self-evaluations, standard debriefing techniques, since these reinforced in most cases subjects' defenses in an unconscious avoidance of criticism. Several recommendations were made for the organization, definition of objectives, experiment selection, crew selection, roles of external management and personnel. In particular, it is felt to be necessary to explain the aims of the mission to the subjects, to give clear and complete information, to establish confident and cooperative relations with the crew. It is essential to allow dialogue, to take opinions and suggestions of the crew seriously, and to establish clear rules of confidentiality. PMID:8814802

Cazes, C; Rosnet, E; Bachelard, C; Le Scanff, C; Rivolier, J

1996-01-01

186

Pathway Controlled Penetration (PcP)  

SciTech Connect

The technical approach employs advanced computational simulation tools to demonstrate how current assets can destroy RWK-RFI-12-0001's HDBT, a tunnel complex with two portals built into the base of a granite mountain. The granite over layer is assumed to be 60 meters thick over both portals and 80 meters over the facility's mission space. Key S&T is the completed development of a highly innovative viscoplastic fracture material model, 3D parallel gas-fracture capabilities into FDEM, and a stochastic handling of the material properties. Phase I - Develop and validate code simulation tools: (1) develop, incorporate and validate AZ-Frac material model for granite; and (2) Develop and incorporate gas-driven-fracture modeling into LANL's FDEM MUNROU code; (3) Develop and incorporate stochastic features into FDEM modeling. Phase II - Conduct PcP analysis on above HDBT: (1) Acquire HDBT design data, develop simulation model; and (2) Evaluate and select most promising defeat alternative. Phase III - Deliver code, train Service target analysts, and conduct simulations against real world HDBTs. PcP uses advanced computer simulations to enhance HDBT functional defeat efforts. Newly developed material models that account for fractural energy coupled with the finite discrete element methodology (FDEM) will provide targeting packages that will create penetration avenues for current or future lethality options. This novel computational approach requires full 3D geologic and structure characterization as well as significant high performance computing capabilities. The goal is to distinctively alter the targeting paradigm by leveraging critical DoD assets along with insitu geologic strata. In other words, assets will utilize underground rock structure to their benefit by creating rubbilization zones that will allow pathway controlled penetration.

Knight, Earl E. [Los Alamos National Laboratory; Rougier, Esteban [Los Alamos National Laboratory; Zubelewicz, Aleksander [Los Alamos National Laboratory

2012-08-29

187

The effect of spacing transverse to the wave direction on the Morison force coefficients in two cylinder groups  

SciTech Connect

This paper provides some results from an experimental study currently being carried out in the Michell laboratory at the University of Melbourne. The principal purpose of the study is to investigate the Morison in-line hydrodynamic force characteristics of slender surface-piercing multi-cylinder structures. The test program has been tailored to provide more detailed observations within the close-spaced region (Separation/Diameter ratio, s/D < 2) of the group interference effect in such multi-cylinder structures over the Keulegan Carpenter range 0 < KC < 20 which encompasses the inertia force dominant Morison regime (KC < 5), as well as the so-called troublesome region (5 < KC < 15) where both drag and inertia force components are significant. Results currently in hand for the side-by-side two-cylinder group configuration are presented which clearly depict the characteristics of this interference effect.

Haritos, N.; Smith, D.J. [Univ. of Melbourne, Victoria (Australia). Dept. of Civil and Environmental Engineering

1995-12-31

188

Evolution equations invariant under two-dimensional space-time Schrdinger group  

NASA Astrophysics Data System (ADS)

The most general second order evolution equation ?t+F(x,t,??*,?x,?x*,?xx, ?xx*)=0, invariant under the Galilei, Galilei-similitude, and Schrdinger groups in two dimensions, is constructed. A preliminary step is a classification of all possible realizations of the corresponding Lie algebras of vector fields in R2C parametrized by x, t, ?, and ?*. Applications of this study include the investigation of nonlinear alternatives to quantum mechanics and nonrelativistic classical field theories. Among the Schrdinger invariant equations, in particular, are found integrable equations, linearizable by contact transformations.

Rideau, G.; Winternitz, P.

1993-02-01

189

PC/104 Embedded IOCs at Jefferson Lab  

SciTech Connect

Jefferson Lab has developed embedded IOCs based on PC/104 single board computers (SBC) for low level control systems. The PC/104 IOCs run EPICS on top of the RTEMS operating system. Two types of control system configurations are used in different applications, PC/104 SBC with commercial PC/104 I/O cards and PC/104 SBC with custom designed FPGA-based boards. RTEMS was built with CEXP shell to run on the PC/104 SBC. CEXP shell provides the function of dynamic object loading, which is similar to the widely used VxWorks operating system. Standard software configurations were setup for PC/104 IOC application development to provide a familiar format for new projects as well as ease the conversion of applications from VME based IOCs to PC/104 IOCs. Many new projects at Jefferson Lab are going to employ PC/104 SBCs as IOCs and some applications have already been running them for accelerator operations. The PC/104 - RTEMS IOC provides a free open source Real-Time Operating System (RTOS), low cost/maintenance, easily installed/ configured, flexible, and reliable solution for accelerator control and 12GeV Upgrade projects.

Jianxun Yan, Trent Allison, Sue Witherspoon, Anthony Cuffe

2009-10-01

190

Building a research group of Space Physics at UAHuntsville -- the impact of an NSF career award  

NASA Astrophysics Data System (ADS)

G. Li (1,2) (1) Department of Physics, University of Alabama in Huntsville Huntsville, AL, 35899 (2) CSPAR, University of Alabama in Huntsville Huntsville, AL, 35899 The author joined the faculty of the department of Physics at University of Alabama in Huntsville in August 2008. He was awarded the NSF Career award ATM-0847719 in 2009. To date, the Career award has provided partial supports to one postdoc, two graduate students and three undergraduate students for a variety of periods. Three publications came out as a result of the award (one of which is first authored by one undergraduate). Another two publications are in preparation. The award also helped the PI to be further recognized by the field of space plasma physics and cosmic ray physics. For example, in July 2009, the PI was awarded the Young Scientist Medal by the International Union of Pure and Applied Physics (IUPAP); in April 2010, the PI won an Oak Ridge Associated Universities (ORAU) 2010 Ralph E. Powe Junior Faculty Enhancement Award. In short, the NSF CAREER has helped the PI to start his career at a level without which, will be impossible.

Li, G.

2011-12-01

191

My Time, My Space (an arts-based group for women with postnatal depression): a project report.  

PubMed

This paper will describe an innovative method of treatment for women with postnatal depression that has been used in the south west of England since 2004 and has now been successfully piloted in other areas of the UK. My Time My Space is an arts-based group for women with postnatal depression that aims to improve mood by reducing social isolation and using creativity to improve self-esteem. Results of the programme will be shared, in addition to the ways in which the project has been implemented using collaborative working with children's centres and building community capacity by engaging local charities. The qualitative results have been collected from participants (n = 30) over the last two years using post-course evaluation forms with open questions to elicit participants' views. The quantitative results of a small pilot study (n = 8) based on pre- and post-group Edinburgh Postnatal Depression Scale scores (EPDS) are also reported. The findings suggest My Time My Space has a positive effect on women's mood and perceived social support, and provides an effective alternative or additional method of treatment for postnatal depression. PMID:23724760

Morton, Alison; Forsey, Philippa

2013-05-01

192

Prediction of molecular crystal structures by a crystallographic QM/MM model with full space-group symmetry.  

PubMed

A crystallographic quantum-mechanical/molecular-mechanical model (c-QM/MM model) with full space-group symmetry has been developed for molecular crystals. The lattice energy was calculated by quantum-mechanical methods for short-range interactions and force-field methods for long-range interactions. The quantum-mechanical calculations covered the interactions within the molecule and the interactions of a reference molecule with each of the surrounding 12-15 molecules. The interactions with all other molecules were treated by force-field methods. In each optimization step the energies in the QM and MM shells were calculated separately as single-point energies; after adding both energy contributions, the crystal structure (including the lattice parameters) was optimized accordingly. The space-group symmetry was maintained throughout. Crystal structures with more than one molecule per asymmetric unit, e.g. structures with Z' = 2, hydrates and solvates, have been optimized as well. Test calculations with different quantum-mechanical methods on nine small organic molecules revealed that the density functional theory methods with dispersion correction using the B97-D functional with 6-31G* basis set in combination with the DREIDING force field reproduced the experimental crystal structures with good accuracy. Subsequently the c-QM/MM method was applied to nine compounds from the CCDC blind tests resulting in good energy rankings and excellent geometric accuracies. PMID:25537386

Mrschel, Philipp; Schmidt, Martin U

2015-01-01

193

Isochrone Ages and Moving Groups of Nearby Stars  

NASA Astrophysics Data System (ADS)

HIPPARCOS parallaxes, proper motions, and apparent magnitudes for nearby field stars allow newly precise estimates of their ages, as well as comparison of space motions with other field stars and known moving groups. We present ages and uncertainties for 150 A, F, G, and K main sequence stars within 20 pc of the Sun, and limits for 30 others, based on interpolation of absolute magnitudes and colors in theoretical isochrones and evolutionary tracks from Bertelli et al. (1994). We also searched for space motions in common between the luminous nearby stars and M main sequence stars in the same 20 pc volume, and for nearby stars with motions parallel to known moving groups and clusters. Comparison is made between isochrone ages and possible moving group assignments. We thank NASA for support.

Mandell, A. M.; Connelley, M. S.; Backman, D. E.

1999-12-01

194

Localization properties of random-mass Dirac fermions from real-space renormalization group.  

PubMed

Localization properties of random-mass Dirac fermions for a realization of mass disorder, commonly referred to as the Cho-Fisher model, are studied on the D-class chiral network. We show that a simple renormalization group (RG) description captures accurately a rich phase diagram: thermal metal and two insulators with quantized ?(xy), as well as transitions (including critical exponents) between them. Our main finding is that, even with small transmission of nodes, the RG block exhibits a sizable portion of perfect resonances. Delocalization occurs by proliferation of these resonances to larger scales. Evolution of the thermal conductance distribution towards a metallic fixed point is synchronized with evolution of signs of transmission coefficients, so that delocalization is accompanied with sign percolation. PMID:21770661

Mkhitaryan, V V; Raikh, M E

2011-06-24

195

The Exploration Atmospheres Working Group's Report on Space Radiation Shielding Materials  

NASA Technical Reports Server (NTRS)

This part of Exploration Atmospheres Working Group analyses focuses on the potential use of nonmetallic composites as the interior walls and structural elements exposed to the atmosphere of the spacecraft or habitat. The primary drive to consider nonmetallic, polymer-based composites as an alternative to aluminum structure is due to their superior radiation shielding properties. But as is shown in this analysis, these composites can also be made to combine superior mechanical properties with superior shielding properties. In addition, these composites can be made safe; i.e., with regard to flammability and toxicity, as well as "smart"; i.e., embedded with sensors for the continuous monitoring of material health and conditions. The analysis main conclusions are that (1) smart polymer-based composites are an enabling technology for safe and reliable exploration missions, and (2) an adaptive, synergetic systems approach is required to meet the missions requirements from structure, properties, and processes to crew health and protection for exploration missions.

Barghouty, A. F.; Thibeault, S. A.

2006-01-01

196

Space-group symmetry fractionalization in a family of exactly solvable models with Z2 topological order  

NASA Astrophysics Data System (ADS)

We study square lattice space-group symmetry fractionalization in a family of exactly solvable models with Z2 topological order in two dimensions. In particular, we have obtained a complete understanding of which distinct types of symmetry fractionalization (symmetry classes) can be realized within this class of models, which are generalizations of Kitaev's Z2 toric code to arbitrary lattices. This question is motivated by earlier work of Essin and one of us (M. H.) [Phys. Rev. B 87, 104406 (2013), 10.1103/PhysRevB.87.104406], where the idea of symmetry classification was laid out, and which, for square lattice symmetry, produces 2080 symmetry classes consistent with the fusion rules of Z2 topological order. This approach does not produce a physical model for each symmetry class, and indeed there are reasons to believe that some symmetry classes may not be realizable in strictly two-dimensional systems, thus raising the question of which classes are in fact possible. While our understanding is limited to a restricted class of models, it is complete in the sense that for each of the 2080 possible symmetry classes, we either prove rigorously that the class cannot be realized in our family of models, or we give an explicit model realizing the class. We thus find that exactly 487 symmetry classes are realized in the family of models considered. With a more restrictive type of symmetry action, where space-group operations act trivially in the internal Hilbert space of each spin degree of freedom, we find that exactly 82 symmetry classes are realized. In addition, we present a single model that realizes all 26=64 types of symmetry fractionalization allowed for a single anyon species (Z2 charge excitation), as the parameters in the Hamiltonian are varied. The paper concludes with a summary and a discussion of two results pertaining to more general bosonic models.

Song, Hao; Hermele, Michael

2015-01-01

197

Inter-Agency Consultative Group for Space Science (IACG): Handbook of Missions and Payloads  

NASA Technical Reports Server (NTRS)

The ACE spacecraft design is based on the Charge Composition Explorer (CCE) built by Johns Hopkins University (JHU) and the Applied Physics Lab (APL) for the AMPTE program. ACE is designed as a spinning spacecraft with its spin axis aligned to the Earth-Sun axis. The ACE launch weight will be approx. 633 kg, including 105 kg of scientific instruments and 184 kg of propellant. Using a Delta-class expendable launch vehicle, ACE will be launched into an L1 libration point (240 R(sub e)) orbit. Telemetry will be 6.7 kbps average, using tape recorder storage with daily readout to DSN. The experiment power requirement is approximately 76 W nominal and 96 W peak. The prime objective of the ACE mission is: (1) to determine accurate elemental and isotropic abundances including solar matter, local interstellar matter and local galactic matter; (2) to study the origin of elements and evolutionary processing in galactic nucleosynthesis, galactic evolution, origin and evolution of the solar system; (3) to study coronal formation and solar-wind acceleration processes; and (4) to study particle acceleration and transport, including coronal shock acceleration, stochastic flare acceleration, interplanetary shock acceleration, and interstellar acceleration and propagation. To accomplish this objective, ACE will perform comprehensive and coordinated determinations of the elemental and isotopic composition of energetic nuclei accelerated on the Sun, in interplanetary space, and from galactic sources. These observations will span five decades in energy, from solar wind to galactic cosmic ray energies, and will cover the element range from H-1 to Zr-40. Comparison of these samples of matter will be used to study the origin and subsequent evolution of both solar system and galactic material by isolating the effects of fundamental processes that include nucleosynthesis, charged and neutral particle separation, bulk plasma acceleration, and the acceleration of suprathermal and high-energy particles.

1994-01-01

198

Behavioral and biological effects of autonomous versus scheduled mission management in simulated space-dwelling groups  

NASA Astrophysics Data System (ADS)

Logistical constraints during long-duration space expeditions will limit the ability of Earth-based mission control personnel to manage their astronaut crews and will thus increase the prevalence of autonomous operations. Despite this inevitability, little research exists regarding crew performance and psychosocial adaptation under such autonomous conditions. To this end, a newly-initiated study on crew management systems was conducted to assess crew performance effectiveness under rigid schedule-based management of crew activities by Mission Control versus more flexible, autonomous management of activities by the crews themselves. Nine volunteers formed three long-term crews and were extensively trained in a simulated planetary geological exploration task over the course of several months. Each crew then embarked on two separate 3-4 h missions in a counterbalanced sequence: Scheduled, in which the crews were directed by Mission Control according to a strict topographic and temporal region-searching sequence, and Autonomous, in which the well-trained crews received equivalent baseline support from Mission Control but were free to explore the planetary surface as they saw fit. Under the autonomous missions, performance in all three crews improved (more high-valued geologic samples were retrieved), subjective self-reports of negative emotional states decreased, unstructured debriefing logs contained fewer references to negative emotions and greater use of socially-referent language, and salivary cortisol output across the missions was attenuated. The present study provides evidence that crew autonomy may improve performance and help sustain if not enhance psychosocial adaptation and biobehavioral health. These controlled experimental data contribute to an emerging empirical database on crew autonomy which the international astronautics community may build upon for future research and ultimately draw upon when designing and managing missions.

Roma, Peter G.; Hursh, Steven R.; Hienz, Robert D.; Emurian, Henry H.; Gasior, Eric D.; Brinson, Zabecca S.; Brady, Joseph V.

2011-05-01

199

LiB12PC, the first boron-rich metal boride with phosphorus--synthesis, crystal structure, hardness, spectroscopic investigations.  

PubMed

We present synthesis, crystal structure, hardness, and IR/Raman and UV/Vis spectra of a new compound with the mean composition LiB(12)PC. Transparent single crystals were synthesised from Ga, Li, B, red phosphorus and C at 1500?C in boron nitride crucibles welded in Ta ampoules. Depending on the type of boron used for the synthesis we obtained colourless, brown and red single crystals with slightly different P/C ratios. Colourless LiB(12)PC crystallizes orthorhombic in the space group Imma (No. 74) with a=10.188(2)?, b=5.7689(11)?, c=8.127(2)? and Z=4. Brown LiB(12)P(0.89)C(1.11) is very similar, but with a lower P content. Red single crystals of LiB(12)P(1.13)C(0.87) have a larger unit cell with a=10.4097(18)?, b=5.9029(7)?, c=8.2044(12)?. EDX measurements confirm that the red crystals contain more phosphorus than the other ones. The crystal structure is characterized by a covalent network of B(12) icosahedra connected by exohedral B-B bonds and P-P, P-C or C-C units. Li atoms are located in interstitials. The structure is closely related to MgB(7), LiB(13)C(2) and ScB(13)C. LiB(12)PC fulfils the electron counting rules of Wade and also Longuet-Higgins. Measurements of Vickers micro-hardness (H(V)=27?GPa) revealed that LiB(12)PC is a hard material. The optical band gaps obtained from UV/Vis spectra match the colours of the crystals. Furthermore we report on the IR and Raman spectra. PMID:21308812

Vojteer, Natascha; Sagawe, Vanessa; Stauffer, Julia; Schroeder, Melanie; Hillebrecht, Harald

2011-03-01

200

Calculating field emission current in nanodiodesA multi-group formalism with space charge and exchange-correlation effects  

NASA Astrophysics Data System (ADS)

Inclusion of electron-electron interaction is essential in nano-diodes to understand the underlying physical phenomenon and tailor devices accordingly. However, both space charge and exchange-correlation interaction involve electrons at different energies and hence a self-consistent multi-energy-group solution of the Schrdinger-Poisson system is required. It is shown here that the existence of a limiting density-dependent potential at low applied voltages allows calculation of the field emission current. Despite additional interactions, a Fowler-Nordheim behaviour is observed. It is also found that the exchange-correlation potential dominates at these voltages in nanogaps and possibly leads to a higher turn-on voltage.

Biswas, Debabrata; Kumar, Raghwendra

2014-03-01

201

The PowerPC Compiler Writer's Guide  

E-print Network

-96. Printed in the United State of America. This notice applies to The PowerPC Compiler Writer's Guide, datedThe PowerPC Compiler Writer's Guide Edited by: Steve Hoxey Faraydon Karim Bill Hay Hank Warren Warthman Associates #12;© International Business Machines Corporation 1996. All rights reserved. 1

Bernstein, Daniel

202

Inorganic structures in space group P3m1; coordinate analysis and systematic prediction of new ferroelectrics.  

PubMed

ICSD Release 2007/1 contains 47 families of inorganic crystal structures, some single-member only, within the 311 entries listed under the polar space group P3m1. Coordinate analysis reveals 12 such families to be candidate ferroelectrics, over a range of confidence levels. Selection is based on the detection of an approach to nonpolar supergroup symmetry, within specified limits, by the atomic arrangement as reported in a confirmed polar space group. The primary source of uncertainty in such predictions is the reliability of the underlying structural determination. The candidates include In(2)ZnS(4), TlSn(2)F(5), Cu(7)Te(4), NaMnSe(2), Na(2)In(2)(Mo(3)O(8))(MoO(4))(2), Nb(3)Br(7)S, Nb(3)TeI(7), fencooperite, Bi(HCOO)(3), Li(NpO(2))(CO(3))(H(2)O)(2), LiPtD(0.66) and Ag(3)(MoO(3)F(3))(Ag(3)(MoO(4))Cl). A total of 20 structures examined are likely to be nonpolar, a further 20 have reduced predictive properties and three others are more likely to retain P3m1 symmetry over a wide thermal range. Substantial uncertainties associated with many of the listed 163 CdI(2), 69 ZnS and 10 SiC polytype structures, together with their low potential for use as possible ferroelectrics, led to their exclusion from fuller analysis. PMID:18641444

Abrahams, S C

2008-08-01

203

A Commutative Model of a Representation of the Group O ( n , 1) X and a Generalized Lebesgue Measure in the Space of Distributions  

Microsoft Academic Search

For an irreducible unitary representation of an O(n, 1) current group, we consider a commutative model obtained by diagonalization with respect to a maximal unipotent subgroup. This model leads to a new measure on the space of distributions. The measure is invariant with respect to an infinite-dimensional linear symmetry group.

M. I. Graev; A. M. Vershik

2005-01-01

204

Coordination of Advanced Solar Observatory (ASO) Science Working Group (SWG) for the study of instrument accommodation and operational requirements on space station  

NASA Technical Reports Server (NTRS)

The objectives are to coordinate the activities of the Science Working Group (SWG) of the Advanced Solar Observatory (ASO) for the study of instruments accommodation and operation requirements on board space station. In order to facilitate the progress of the objective, two conferences were organized, together with two small group discussions.

Wu, S. T.

1989-01-01

205

Astronaut Jeffrey Hoffman with WF/PC during third STS-61 EVA  

NASA Technical Reports Server (NTRS)

Astronaut Jeffrey A. Hoffman, anchored on the end of the Remote Manipulator System (RMS) arm, is pictured with the Wide Field/Planetary Camera (WF/PC I) during the third of the five STS-61 space walks. Astronauts Hoffman and F. Story Musgrave, seen near the stowage area for the WF/PC, had earlier installed the new camera (note white rectangle) on lower portion of telescope.

1993-01-01

206

Induction of cytoprotective autophagy in PC-12 cells by cadmium  

SciTech Connect

Highlights: Cadmium can promote early upregulation of autophagy in PC-12 cells. Autophagy precedes apoptosis in cadmium-treated PC-12 cells. Cadmium-induced autophagy is cytoprotective in PC-12 cells. Class III PI3K/beclin-1/Bcl-2 signaling pathway plays a positive role in cadmium-triggered autophagy. -- Abstract: Laboratory data have demonstrated that cadmium (Cd) may induce neuronal apoptosis. However, little is known about the role of autophagy in neurons. In this study, cell viability decreased in a dose- and time-dependent manner after treatment with Cd in PC-12 cells. As cells were exposed to Cd, the levels of LC3-II proteins became elevated, specific punctate distribution of endogenous LC3-II increased, and numerous autophagosomes appeared, which suggest that Cd induced a high level of autophagy. In the late stages of autophagy, an increase in the apoptosis ratio was observed. Likewise, pre-treatment with chloroquine (an autophagic inhibitor) and rapamycin (an autophagic inducer) resulted in an increased and decreased percentage of apoptosis in contrast to other Cd-treated groups, respectively. The results indicate that autophagy delayed apoptosis in Cd-treated PC-12 cells. Furthermore, co-treatment of cells with chloroquine reduced autophagy and cell activity. However, rapamycin had an opposite effect on autophagy and cell activity. Moreover, class III PI3 K/beclin-1/Bcl-2 signaling pathways served a function in Cd-induced autophagy. The findings suggest that Cd can induce cytoprotective autophagy by activating class III PI3 K/beclin-1/Bcl-2 signaling pathways. In sum, this study strongly suggests that autophagy may serve a positive function in the reduction of Cd-induced cytotoxicity.

Wang, Qiwen [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China) [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China); Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009 (China); Bijie Pilot Area Research Institute of Bijie University, Bijie 551700 (China); Zhu, Jiaqiao; Zhang, Kangbao; Jiang, Chenyang; Wang, Yi; Yuan, Yan; Bian, Jianchun; Liu, Xuezhong; Gu, Jianhong [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China) [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China); Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009 (China); Liu, Zongping, E-mail: liuzongping@yzu.edu.cn [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China) [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China); Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009 (China)

2013-08-16

207

Scale-PC shielding analysis sequences  

SciTech Connect

The SCALE computational system is a modular code system for analyses of nuclear fuel facility and package designs. With the release of SCALE-PC Version 4.3, the radiation shielding analysis community now has the capability to execute the SCALE shielding analysis sequences contained in the control modules SAS1, SAS2, SAS3, and SAS4 on a MS- DOS personal computer (PC). In addition, SCALE-PC includes two new sequences, QADS and ORIGEN-ARP. The capabilities of each sequence are presented, along with example applications.

Bowman, S.M.

1996-05-01

208

Finite part of operator K-theory for groups finitely embeddable into Hilbert space and the degree of non-rigidity of manifolds.  

E-print Network

In this paper, we study lower bounds on the K-theory of the maximal $C^*$-algebra of a discrete group based on the amount of torsion it contains. We call this the finite part of the operator K-theory and give a lower bound that is valid for a large class of groups, called the "finitely embeddable groups". The class of finitely embeddable groups includes all residually finite groups, amenable groups, Gromov's monster groups, virtually torsion free groups (e.g. $Out(F_n)$), and any group of analytic diffeomorphisms of an analytic connected manifold fixing a given point. It is an open question if every countable group is finitely embeddable. We apply this result to measure the degree of non-rigidity for any compact oriented manifold $M$ with dimension $4k-1$ $(k>1)$. We derive a lower bound on the rank of the structure group $S(M)$ in this case. For a compact Riemannian manifold $M$ with dimension greater than or equal to 5 and positive scalar curvature metric, there is an abelian group $P(M)$ that measures the size of the space of all positive scalar curvature metrics on $M$. We obtain a lower bound on the rank of the abelian group $P(M)$ when the compact smooth spin manifold $M$ has dimension $2k-1$ $(k>2)$ and the fundamental group of $M$ is finitely embeddable.

Shmuel Weinberger; Guoliang Yu

209

E-Books and the Tablet PC.  

ERIC Educational Resources Information Center

Highlights the emerging technologies of e-books, electronic versions of texts, and the Tablet PC, a new hybrid laptop computer and personal digital assistant that features a writing tablet and stylus-based input/navigation. (Author/VWL)

Goodwin-Jones, Bob

2003-01-01

210

Effects of TRPM8 on the proliferation and angiogenesis of prostate cancer PC-3 cells in vivo  

PubMed Central

Prostate cancer is a significant health concern. In the early stages, prostate cancer cells depend on androgens for growth and survival, hence androgen-ablation therapy at this time may be effective in causing tumor regression. However, treatment options for advanced hormone-refractory prostate cancers are still relatively inefficient. This study aimed to investigate the possible effects of TRPM8 on the proliferation and angiogenesis of androgen-independent cancer PC-3 cells in vivo. Thirty male nude mice were divided into three groups: the PC-3, PC-3-vector and PC-3-TRPM8 groups. PC-3, PC-3-vector and PC-3-TRPM8 cells were respectively inoculated in the right flank to establish a transplanted tumor model. The mice were treated daily for four weeks and each group was examined by histology and immunohistochemical staining for CD34, FAK and PCNA. A CD34 marked microvascular density (MVD) test was performed. Western blot analysis was used to detect the VEGF protein expression level. Compared to the PC-3 and PC-3-vector groups, the PC-3-TRPM8 group revealed a decrease in tumor volume (P=0.000 and P=0.000, respectively), MVD (P=0.045 and P=0.041, respectively), VEGF (P=0.000 and P=0.000, respectively), FAK and PCNA. The correlation between MVD and VEGF was positive (r=0.419; P=0.021). These data show that the overexpression of TRPM8 had a negative effect on the proliferation and angiogenesis progression of PC-3 cells in vivo. PMID:22848290

ZHU, GUANGBIN; WANG, XINGHUAN; YANG, ZHONGHUA; CAO, HONG; MENG, ZHE; WANG, YONGZHI; CHEN, DONG

2011-01-01

211

The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations  

E-print Network

We present uniformly measured star formation histories (SFHs) of 40 Local Group dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with $\\tau$ $\\sim$ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs (dTrans), and dwarf ellipticals (dEs) can be approximated by the combination of an exponentially declining SFH ($\\tau$ $\\sim$ 3-4 Gyr) for lookback ages $>$ 10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z=2 ranges considerably (80\\%...

Weisz, Daniel R; Skillman, Evan D; Holtzman, Jon; Gilbert, Karoline M; Dalcanton, Julianne J; Williams, Benjamin F

2014-01-01

212

Practical Pocket PC Application w/Biometric Security  

NASA Technical Reports Server (NTRS)

I work in the Flight Software Engineering Branch, where we provide design and development of embedded real-time software applications for flight and supporting ground systems to support the NASA Aeronautics and Space Programs. In addition, this branch evaluates, develops and implements new technologies for embedded real-time systems, and maintains a laboratory for applications of embedded technology. The majority of microchips that are used in modern society have been programmed using embedded technology. These small chips can be found in microwaves, calculators, home security systems, cell phones and more. My assignment this summer entails working with an iPAQ HP 5500 Pocket PC. This top-of-the-line hand-held device is one of the first mobile PC's to introduce biometric security capabilities. Biometric security, in this case a fingerprint authentication system, is on the edge of technology as far as securing information. The benefits of fingerprint authentication are enormous. The most significant of them are that it is extremely difficult to reproduce someone else's fingerprint, and it is equally difficult to lose or forget your own fingerprint as opposed to a password or pin number. One of my goals for this summer is to integrate this technology with another Pocket PC application. The second task for the summer is to develop a simple application that provides an Astronaut EVA (Extravehicular Activity) Log Book capability. The Astronaut EVA Log Book is what an astronaut would use to report the status of field missions, crew physical health, successes, future plans, etc. My goal is to develop a user interface into which these data fields can be entered and stored. The applications that I am developing are created using eMbedded Visual C++ 4.0 with the Pocket PC 2003 Software Development Kit provided by Microsoft.

Logan, Julian

2004-01-01

213

The behavioural and physiological reactions of farmed red deer to transport: effects of sex, group size, space allowance and vehicular motion  

Microsoft Academic Search

Sixty yearling red deer (30 males, 30 females), comprising eight single-sex groups of either 5 or 10 animals, were loaded onto a livestock transporter for 3 h, during which they were either transported or remained stationary, at one of two space allowances (males: 0.5 m2 or 1 m2\\/deer, females: 0.4 m2 or 0.8 m2\\/deer). One group was tested each day,

P. N Grigor; P. J Goddard; C. A Littlewood

1998-01-01

214

Isomorphic complexes formed by recrystallisation of M(II)Pc (M(II) = Mg, Mn and Zn) in liquid 2-amino-3-picoline  

NASA Astrophysics Data System (ADS)

Three isomorphic, Mg, Mn and Zn phthalocyaninato complexes monoaxially ligated by 2-amino-3-picoline (2A3P) are obtained. They crystallise with 2A3P molecule as solvent molecule in the centrosymmetric space group P2 1/ c of monoclinic system. The central M(II) atom in these complexes, M(II)Pc(2A3P), is coordinated by four isoindole N atoms of Pc macrocycle in equatorial position, and by ring N atom of 2A3P molecule in an axial position. The M(II) due to the interaction with an axial 2A3P molecule is significantly displaced from the plane defined by four isoindole N atoms of Pc macrocycle toward the ring N atom of 2A3P molecule. The stability of these complexes in solid was analysed by thermogravimetric measurements. The Mg and Zn complexes in solution are stable under air condition, while the Mn complex is moderately stable in solution and after several days transforms into ?-oxo manganese(III) phthalocyanine complex. The magnetic susceptibility of the MnPc(2A3P) 2A3P complex shows the Curie-Weiss behaviour in the temperature range of 300-75 K. The calculated ?eff indicates on high-spin complex. Below 75 K, the ?eff drastically lowered to the value of 3.62 ? B indicating the intermediate-spin complex. In addition, the co-crystals of 2:1 composition of 2A3P:1,2-dicyanobenzene were isolated during the preparation of the MgPc(2A3P) 2A3P.

Janczak, Jan; Kubiak, Ryszard; Bukowska, Ewa

2009-11-01

215

Relationship between PC index and interplanetary electric field EKL under actual conditions of varying solar wind  

NASA Astrophysics Data System (ADS)

The PC index was introduced as an indicator of magnetic activity in the polar caps generated by the geoeffective interplanetary electric field E _{KL} determined in accordance with Kan and Lee [1979]. The PC index is calculated basing on magnetic data (?F) from near-pole stations Thule and Vostok with use of the statistically justified coefficients of regression ? and ? linking the polar cap magnetic disturbance vectors ?F with the electric field E _{KL}. As a result, the PC index is defined as a value of the polar cap magnetic disturbance standardized with the intensity of the interplanetary electric field EKL regardless of season, UT and hemisphere. Statistically the appropriate values PC and E _{KL} well correlate, however in concrete situations PC and E _{KL} may be quite differ, because E _{KL} characterizes the state of the solar wind far upstream of the magnetosphere, whereas PC characterizes the energy that entered into magnetosphere, Analysis of consistencies and discrepancies between PC and E _{KL} under conditions of different solar wind parameters was carried for all events with magnetic substorms (N=1798) and magnetic storms (N=203) observed in epoch of maximal solar activity (1998-2001). Thus, the solar wind geoefficiency was estimated by independent indicators, such as AL and Dst indices characterizing magnetic activity within the magnetosphere. The essential attention was given also to geoefficiency of sudden pulses of the solar wind dynamic pressure. The results of the analysis were applied to derive the method to nowcast the magnetosphere state, including estimation of the model PC, AL and Dst indices calculated by actual measurement of E _{KL} in the point L1 under conditions of varying solar wind. It is demonstrated that the PC index can be successfully used to monitor space weather and the readiness of the magnetosphere to producing substorm or storm.

Troshichev, Oleg; Smirnov, Michael

216

Group dynamics in a long-term blind endeavor on Earth: An analog for space missions (Lewis & Clark Expedition group dynamic analysis)  

Microsoft Academic Search

In 1803, President Thomas Jefferson set fourth a military expedition led by Captains M. Lewis and W. Clark (Lewis and Clark Expedition) on an exploration that would become an everlasting part of US national history and pride. Looking back at the events of this exploration, there are many similarities to the experiences future human space explorers will face as we

M. Allner; V. Rygalov

2008-01-01

217

Young Stars near Earth: The Octans-Near Association and Castor Moving Group  

NASA Astrophysics Data System (ADS)

All cataloged stellar moving groups and associations with ages <=100 Myr and within 100 pc of Earth have Galactic space motions (UVW) situated in a "good box" with dimensions ~20 km s-1 on a side. Torres et al. defined the Octans Association as a group of 15 stars with age "20 Myr?" and located ~140 pc from Earth, but with average V space velocity -3.6 km s-1 that is well outside of the good box. We present a list of 14 Hipparcos star systems within 100 pc of Earth that we call "Octans-Near"; these systems have UVW similar to those of the much more distant Octans Association. The Octans-Near stars have apparent ages between about 30 and 100 Myr and their relationship to the Octans Association stars is unclear. Six additional star systems have UVW similar to those of Octans-Near stars and likely ages <=200 Myr. These six systems include the late-type binary star EQ Peg6.2 pc from Earth with likely age <=100 Myr and thus likely to be the nearest known pre-main sequence star system. The UVW of stars in a previously proposed ~200 Myr old Castor moving group are not too dissimilar from the UVW of Octans-Near stars. However, stars in the Castor groupif it exists at allare mostly substantially older than 200 Myr and thus generally can readily be distinguished from the much younger Octans-Near stars.

Zuckerman, B.; Vican, Laura; Song, Inseok; Schneider, Adam

2013-11-01

218

D-Side: A Facility and Workforce Planning Group Multi-criteria Decision Support System for Johnson Space Center  

NASA Technical Reports Server (NTRS)

"To understand and protect our home planet, to explore the universe and search for life, and to inspire the next generation of explorers" is NASA's mission. The Systems Management Office at Johnson Space Center (JSC) is searching for methods to effectively manage the Center's resources to meet NASA's mission. D-Side is a group multi-criteria decision support system (GMDSS) developed to support facility decisions at JSC. D-Side uses a series of sequential and structured processes to plot facilities in a three-dimensional (3-D) graph on the basis of each facility alignment with NASA's mission and goals, the extent to which other facilities are dependent on the facility, and the dollar value of capital investments that have been postponed at the facility relative to the facility replacement value. A similarity factor rank orders facilities based on their Euclidean distance from Ideal and Nadir points. These similarity factors are then used to allocate capital improvement resources across facilities. We also present a parallel model that can be used to support decisions concerning allocation of human resources investments across workforce units. Finally, we present results from a pilot study where 12 experienced facility managers from NASA used D-Side and the organization's current approach to rank order and allocate funds for capital improvement across 20 facilities. Users evaluated D-Side favorably in terms of ease of use, the quality of the decision-making process, decision quality, and overall value-added. Their evaluations of D-Side were significantly more favorable than their evaluations of the current approach. Keywords: NASA, Multi-Criteria Decision Making, Decision Support System, AHP, Euclidean Distance, 3-D Modeling, Facility Planning, Workforce Planning.

Tavana, Madjid

2005-01-01

219

CASE STUDY -- LEAN 94-02: A Case Study of Self-Directed Work Teams at Boeing Defense and Space Group - Corinth  

E-print Network

Boeing Defense & Space Group - Corinth (BD&SG-C) is a self-directed team based unionized facility in the defense and commercial aircraft industry. The plant was a greenfield start-up in 1987. Due to the nature of the defense ...

Klein, Janice

1994-02-24

220

Ternary phase diagram of dipalmitoyl-PC/dilauroyl-PC/cholesterol: nanoscopic domain formation driven by cholesterol.  

PubMed Central

A ternary phase diagram is proposed for the hydrated lamellar lipid mixture dipalmitoylphosphatidylcholine/dilauroylphosphatidylcholine/cholesterol (DPPC/DLPC/cholesterol) at room temperature. The entire composition space has been thoroughly mapped by complementary experimental techniques, revealing interesting phase behavior that has not been previously described. Confocal fluorescence microscopy shows a regime of coexisting DPPC-rich ordered and DLPC-rich fluid lamellar phases, having an upper boundary at apparently constant cholesterol mole fraction chi(chol) approximately 0.16. Fluorescence resonance energy transfer experiments confirm the identification and extent of this two-phase regime and, furthermore, reveal a 1-phase regime between chi(chol) approximately 0.16 and 0.25, consisting of ordered and fluid nanoscopic domains. Dipyrene-PC excimer/monomer measurements confirm the new regime between chi(chol) approximately 0.16 and 0.25 and also show that rigidly ordered phases seem to disappear around chi(chol) approximately 0.25. This study should be considered as a step toward a more complete understanding of lateral heterogeneity within biomembranes. Cholesterol may play a role in domain separation on the nanometer scale. PMID:11371452

Feigenson, G W; Buboltz, J T

2001-01-01

221

Emissions tracking system (ETS-PC) software  

SciTech Connect

The U.S. EPA Acid Rain Division developed and is maintaining the Emissions Tracking System (ETS) to receive, store and analyze data from continuous emissions monitors (CEMs) submitted by utilities affected by the 1990 Clean Air Act. This paper will describe ETS-PC, a PC application developed by EPA to assist utilities in analyzing and submitting emission data files each quarter. ETS-PC includes quality assurance software which helps utilities identify possible errors in their quarterly data files (QDFs) prior to submission. It also includes communications software which allows utilities to transfer QDFs via modem directly to the EPA mainframe computer located in Research Triangle Park, NC. After a file is transferred, users are provided with immediate feedback from the mainframe in the form of a file transfer receipt and summary.

Weatherbee, J. Jr.; Kress, T. [Science Applications International Corp., McLean, VA (United States)

1997-12-31

222

PC workstation 1 Gustavb, Wikimedia Commons.http://en.wikipedia.org/wiki/Image:Personal_computer,_exploded_5.svg  

E-print Network

1 PC PC 1 PC PC 1 PC PC PC PC 1 1 #12;1 1.1 PC PC PC PC PC workstation PC 1.1.1 hard soft 1.1.2 PC," " CSV Microsoft Word (doc) Microsoft Word Microsoft Excel (xls) Microsoft Excel Portable Document Format JPEG GIF (gif) CompuServe 256 PNG (png) Portable Network Graphics GIF GIF JPEG JPEG 7 #12;1 PNG Web Web

Kasahara, Hironori

223

A STEREOSCOPIC RANGING SYSTEM USING STANDARD PC TECHNOLOGY  

E-print Network

this digital data file. Data transfer directly to PC memory was slow in previous PC generations. Frame grabbersA STEREOSCOPIC RANGING SYSTEM USING STANDARD PC TECHNOLOGY Nick Nelissen*, Rolf Koch* and Alec for an underwater ROV Station Keeping System. Advancements in PC technology make it possible to use a relatively

224

Fabrication of ZnPc/protein nanohorns for double photodynamic and hyperthermic cancer phototherapy  

PubMed Central

Multifunctionalization of carbon nanotubules is easily achieved by attaching functional molecules that provide specific advantages for microscopic applications. We fabricated a double photodynamic therapy (PDT) and photohyperthermia (PHT) cancer phototherapy system that uses a single laser. Zinc phthalocyanine (ZnPc) was loaded onto single-wall carbon nanohorns with holes opened (SWNHox), and the protein bovine serum albumin (BSA) was attached to the carboxyl groups of SWNHox. In this system, ZnPc was the PDT agent, SWNHox was the PHT agent, and BSA enhanced biocompatibility. The double phototherapy effect was confirmed in vitro and in vivo. When ZnPc-SWNHox-BSA was injected into tumors that were subcutaneously transplanted into mice, the tumors almost disappeared upon 670-nm laser irradiation. In contrast, the tumors continued to grow when only ZnPc or SWNHox-BSA was injected. We conclude that carbon nanotubules may be a valuable new tool for use in cancer phototherapy. PMID:18815374

Zhang, Minfang; Murakami, Tatsuya; Ajima, Kumiko; Tsuchida, Kunihiro; Sandanayaka, Atula S. D.; Ito, Osamu; Iijima, Sumio; Yudasaka, Masako

2008-01-01

225

Electroacupuncture at PC6 or ST36 Influences the Effect of Tacrine on the Motility of Esophagus.  

PubMed

Aim. To investigate the mechanisms of gastrointestinal side effects of tacrine, and find treatment methods with electroacupuncture (EA). Methods. Twenty-five healthy cats were randomly divided into 5 groups: gastric-distention group (model group), tacrine group (cholinesterase inhibitor), tacrine + sham acupoint group (control group), tacrine + PC6 (neiguan) group, and tacrine + ST36 (zusanli) group, with 5 cats in each group. Saline 2?mL i.p. was given 30?min before gastric distention in model group. Tacrine 5.6?mg/kg i.p. was given 30 minutes before gastric distention in the other groups. Tacrine + sham acupoint group (control group), tacrine + PC6 group, and tacrine + ST36 group received EA at corresponding acupoints during gastric distention. The frequency of TLESRs and LESP were recorded by using a perfused sleeve assembly. Results. Compared with the model group, tacrine significantly increased the frequency of gastric distention-induced TLESR (P < 0.05) but did not influence the rate of common cavity during TLESR. Tacrine significantly increased the LESP, which could not remain during gastric distention. EA at PC6 could decrease the frequency of TLESR and maintain the increase of LESP, but EA at ST36 did not have these effects. Conclusion. Tacrine can significantly increase the gastric distention-induced transient lower esophageal sphincter relaxations (TLESRs). Electroacupuncture (EA) at PC6 may reverse the above side effect. PMID:24808917

Wang, Chi; Chen, Xin; Xie, Peng-Yan

2014-01-01

226

Effects of row spacing, seed rate and maturity group on late planted soybean under irrigated and dryland  

E-print Network

of the soybean acreage is double cropped after winter wheat harvest in June. This results in a soybean planting (Great Plains Mfg., Salina, KS) with 7 rows spaced at 7.5 inches. Inoculants, soil #12;fertility

Balasundaram, Balabhaskar "Baski"

227

A prototype PC-based system of giving color estimation ability to monochrome security cameras  

Microsoft Academic Search

A prototype PC-based system of giving color estimation ability to monochrome security cameras has been developed based on the novel concept. The novel concept can be divided into 3 stages. First, space-variant color filter is put onto the lens of the monochrome security camera. Secondly, when a crime takes place, the camera records suspected person. Finally, just after the crime,

Yoichi Sugita; Yusaku Fujii; Naoya Ohta; Hiroshi Ueda; Masayuki Yokota; Ryosuke Sakurai

2007-01-01

228

CRYSTALLOGRAPHIC POINT AND SPACE  

E-print Network

CRYSTALLOGRAPHIC POINT AND SPACE GROUPS Andy Elvin June 10, 2013 #12;Contents Point and Space no reflection axes #12;Cube and Octahedron are dual Symmetries under Oh #12;Space Groups Subgroups of E(3) Point Group + Translation { R | 0 }{ E | t }a = { R | t }a = Ra + t 230 Space Groups 73 symmorphic space

California at Santa Cruz, University of

229

Tritium dose overestimates by CAP88-PC.  

PubMed

The dose assessment software CAP88-PC may overestimate doses from tritium under some conditions. The overestimates are linked to three key assumptions implicit in the software that may not be immediately parent. The three assumptions are (1) the contribution of home grown food, (2) the distances at which food is produced, and (3) the number of people consuming locally produced food. PMID:9930839

Parks, B S

1999-02-01

230

PC Kiosk Trends in Rural India  

ERIC Educational Resources Information Center

This article presents a series of preliminary, quantitative results on rural PC kiosks in India. An analysis of the data confirms many expected trends and correlations and shows that kiosks still face the challenge of sustainability as a business. This study is based on questionnaires presented to kiosk operators and customers of kiosks operated

Toyama, Kentaro; Kiri, Karishma; Menon, Deepak; Sethi, Suneet; Pal, Joyojeet; Srinivasan, Janaki

2006-01-01

231

Jargon that Computes: Today's PC Terminology.  

ERIC Educational Resources Information Center

Discusses PC (personal computer) and telecommunications terminology in context: Integrated Services Digital Network (ISDN); Asymmetric Digital Subscriber Line (ADSL); cable modems; satellite downloads; T1 and T3 lines; magnitudes ("giga-,""nano-"); Central Processing Unit (CPU); Random Access Memory (RAM); Universal Serial Bus (USB); "Firewire,"

Crawford, Walt

1997-01-01

232

A Graphical User Interface for PC GAMESS  

NSDL National Science Digital Library

GAMESS is a set of computational chemistry tools available free for several computing platforms. Using the set of tools described here along with the pcgRun tool provided allows these tools to be used on the ubiquitous Windows PC with a graphic interface preferred by many of us over the command line.

233

Experience using EPICS on PC platforms  

SciTech Connect

The Experimental Physics and Industrial Control System (EPICS) has been widely adopted in the accelerator community. Although EPICS is available on many platforms, the majority of implementations have used UNIX workstations as clients, and VME- or VXI-based processors for distributed input output controllers. Recently, a significant portion of EPICS has been ported to personal computer (PC) hardware platforms running Microsoft`s operating systems, and also Wind River System`s real time vxWorks operating system. This development should significantly reduce the cost of deploying EPICS systems, and the prospect of using EPICS together with the many high quality commercial components available for PC platforms is also encouraging. A hybrid system using both PC and traditional platforms is currently being implemented at LANL for LEDA, the low energy demonstration accelerator under construction as part of the Accelerator Production of Tritium (APT) project. To illustrate these developments the authors compare their recent experience deploying a PC-based EPICS system with experience deploying similar systems based on traditional (UNIX-hosted) EPICS hardware and software platforms.

Hill, J.O. [Los Alamos National Lab., NM (United States); Kasemire, K.U. [Univ. Osnabruck (Germany). Fachbereich Physik

1998-03-01

234

Stretch Your PC Dollars--Buy Clones.  

ERIC Educational Resources Information Center

Relates how the story of how San Francisco State University evaluated IBM PC look-alikes, considered some of the risks involved, and decided to purchase over 100 of them. Questions of compatibility, vendor longevity, support, and other risk management issues are discussed. (Author/MLW)

True, John

1986-01-01

235

Multitasking Operating Systems for the IBM PC.  

ERIC Educational Resources Information Center

The ability of a microcomputer to execute several programs at the same time is called "multitasking." The nature and use of one multitasking operating system Concurrent PC-DOS from Digital Research (the developers of the CP/M operating system) are discussed. (JN)

Owen, G. Scott

1985-01-01

236

GUI for PC auto-shutdown  

Microsoft Academic Search

Computer is a part and parcel of our daily life. It is being widely used at homes, offices, schools and industries. It is now an important issue to save user program and data as well as hardware and software of the personal computer (PC) itself from damage and corruption due to sudden power failure. This paper presents the solution of

Mohd. Liakot Ali; Rafiqul Islam; A. Siti Anom; M. Y. Nurul Amziah

2008-01-01

237

OAST Space Theme Workshop. Volume 3: Working Group Summary. 5: Propulsion (P-1). A. Summary Statement. B. Technology Needs (Form 1). C. Priority Assessments (Form 2)  

NASA Technical Reports Server (NTRS)

All themes require some form of advanced propulsion capabilities to achieve their stated objectives. Requirements cover a broad spectrum ranging from a new generation of heavy lift launch vehicles to low thrust, long lift system for on-orbit operations. The commonality extant between propulsive technologies was established and group technologies were grouped into vehicle classes by functional capability. The five classes of launch vehicles identified by the space transportation theme were augmented with a sixth class, encompassing planetary and on-orbit operations. Propulsion technologies in each class were then ranked, and assigned priority numbers. Prioritized technologies were matched to theme requirements.

1976-01-01

238

Space group and phonon symmetry of (RE1Ba 2 Cu 3 O 7) m (RE2Ba 2 Cu 3 O 7) n superlattices  

NASA Astrophysics Data System (ADS)

It is shown by group theory methods that the symmetry of (RE1Ba 2 Cu 3 O 7) m (RE2Ba 2 Cu 3 O 7) n superlattices grown along [1 0 0], [0 1 0] and [0 0 1] crystallographic directions is described by the same space group Pmmm ( D2 h1) as that of the initial bulk crystalline structure. The arrangement of atoms over Wyckoff positions in multiplied primitive cells of the superlattices is obtained for each of growth directions and all ( m, n) combinations. Symmetry classification of phonons at k = 0 is also carried out. Some features of phonon spectra of ultrathin superlattices are briefly discussed.

Mirovitskii, V. Yu.

1992-09-01

239

A 2.2? resolution structure of the USP7 catalytic domain in a new space group elaborates upon structural rearrangements resulting from ubiquitin binding.  

PubMed

A sparse-matrix screen for new crystallization conditions for the USP7 catalytic domain (USP7CD) led to the identification of a condition in which crystals grow reproducibly in 24-48?h. Variation of the halide metal, growth temperature and seed-stock concentration resulted in a shift in space group from P21 with two molecules in the asymmetric unit to C2 with one molecule in the asymmetric unit. Representative structures from each space group were determined to 2.2? resolution and these structures support previous findings that the catalytic triad and switching loop are likely to be in unproductive conformations in the absence of ubiquitin (Ub). Importantly, the new structures reveal previously unobserved electron density for blocking loop 1 (BL1) residues 410-419. The new structures indicate a distinct rearrangement of the USP7 BL1 compared with its position in the presence of bound Ub. PMID:24598911

Molland, Katrina; Zhou, Qing; Mesecar, Andrew D

2014-03-01

240

Synchronization of heart rate indices of human and Pc5 pulsations in the geomagnetic quiet conditions  

NASA Astrophysics Data System (ADS)

Geomagnetic pulsations with duration of the period over 150 seconds (Pc5-6) are present in the magnetosphere almost constantly. Unlike other types of geomagnetic pulsations, they are characterized by high amplitudes reaching in auroral latitudes 30-100 nT, and even 300 - 600 nT in time of significant geomagnetic disturbances [1]. To date, it is generally accepted that the classic morning and afternoon Pc5 pulsations in the magnetosphere are toroidal Alfven resonance vibrations of the geomagnetic field lines [2, 3]. It was revealed that the basic oscillation periods, presented in heart rate variability of healthy subjects, in conditions of rest, at each time point substantially coincide with the periods of oscillation of the X-vector components of the geomagnetic field in the frequency range of Pc5-6 pulsations. Synchronization effect was observed in approximately 60% of cases [4]. The above statement is based on the results of more than 100 experiments (recording time from 60 to 200 min), conducted in the period 2011-2013 in various research groups [4]. In total, 37 volunteers in the age range 18-65 yrs took part in the experiments. Experiments were performed in Pushchino and Khimki (Moscow region), Arkhangelsk, Tomsk, Sofia (Bulgaria), as well as at the station Starorusskaya (Leningrad region). The geomagnetic data were obtained from INTERMAGNET network (http://ottawa.intermagnet.org/Welcom_e.php). From a biophysical point of view, the observed effects of timing fluctuations of heart rate of healthy subjects with the oscillations of the magnetic induction vector of the GMF could be an effective tool for solving one of the most actual problems in heliobiophysics, namely the identification of specific physiological mechanisms of biosystems response to low-intensity variations external factors. 1. Pilipenko V.A., Kleimenova N.G., Kozyreva O.V., Yumoto K., Bitterly G. Geomagnetism and aeronomy, 1997, V. 37, ?.3, P. 64-76 2. Chen L. and Hasegawa A. J.Geophys. Res. 1974. Vol.79,P.1024-1032 3. Southwood D.J. Planet. Space Sci. 1974. Vol.22, P.483-491. 4.Zenchenko T.A., Medvedeva A.A., Khorseva N.I., Breus T.K. // Geophysical Processes and Biosphere. 2013. V. 12. ? 4. P. 73-84

Zenchenko, Tatiana

241

Regulation of PrPC signaling and processing by dimerization  

PubMed Central

The cellular prion protein (PrPC) is a glycosylphosphatidylinositol (GPI)-anchored protein present at the cell surface. PrPC N-terminal moiety is intrinsically disordered and is able to interact with a variety of ligands. Physiological ligands have neurotrophic activity, whilst others, including protein toxic oligomers, have neurotoxic functions. These two opposite activities involve different interacting partners and result from different PrPC-activated signaling pathways. Remarkably, PrPC may be inactivated either by physiological endoproteolysis and release of the N-terminal domain, or by ectodomain shedding. Ligand-induced PrPC dimerization or enforced dimerization of PrPC indicate that PrPC dimerization represents an important molecular switch for both intracellular signaling and inactivation by the release of PrPC N-terminal domain or shedding. In this review, we summarize evidence that cell surface receptor activity of PrPC is finely regulated by dimerization. PMID:25364762

Roucou, Xavier

2014-01-01

242

Infrared Space Observatory Observations of the 53W002 Group at 6.7 Microns: In Search of the Oldest Stellar Populations at z = 2.4  

Microsoft Academic Search

We present a deep Infrared Space Observatory (ISO) observation at 6.7 mum of the 53W002 group of galaxies and active galactic nuclei (AGNs) at z=2.4. This approximately samples the emitted K band. Faint, blue star-forming objects are not detected, as expected from their very blue color across the emitted optical and UV spectrum. However, 53W002 itself is detected at the

William C. Keel; Wentao Wu; Paul P. van der Werf; Rogier A. Windhorst; James S. Dunlop; Stephen A. Eales; Ian Waddington; Martha Holmes

2004-01-01

243

PC-SEAPAK user's guide, version 4.0  

NASA Technical Reports Server (NTRS)

PC-SEAPAK is designed to provide a complete and affordable capability for processing and analysis of NOAA Advanced Very High Resolution Radiometer (AVHRR) and Nimbus-7 Coastal Zone Color Scanner (CZCS) data. Since the release of version 3.0 over a year ago, significant revisions were made to the AVHRR and CZCS programs and to the statistical data analysis module, and a number of new programs were added. This new version has 114 procedures listed in its menus. The package continues to emphasize user-friendliness and interactive data analysis. Additionally, because the scientific goals of the ocean color research being conducted have shifted to larger space and time scales, batch processing capabilities were enhanced, allowing large quantities of data to be easily ingested and analyzed. The development of PC-SEAPAK was paralled by two other activities that were influential and assistive: the global CZCS processing effort at GSFC and the continued development of VAX-SEAPAK. SEAPAK incorporates the instrument calibration and support all levels of data available from the CZCS archive.

Mcclain, Charles R.; Fu, Gary; Darzi, Michael; Firestone, James K.

1992-01-01

244

Using Innovative Outliers to Detect Discrete Shifts in Dynamics in Group-Based State-Space Models  

ERIC Educational Resources Information Center

Outliers are typically regarded as data anomalies that should be discarded. However, dynamic or "innovative" outliers can be appropriately utilized to capture unusual but substantively meaningful shifts in a system's dynamics. We extend De Jong and Penzer's 1998 approach for representing outliers in single-subject state-space models to a

Chow, Sy-Miin; Hamaker, Ellen L.; Allaire, Jason C.

2009-01-01

245

Space, time and the pattern of individual associations in a group-living species: Sanderlings have no friends  

Microsoft Academic Search

The persistence of flock membership through time and space was examined for wintering sanderlings Calidris alba at Bodega Bay, California from October 1978 to March 1981. Observed patterns of association were then compared with those expected from a null model: that the set of birds within a given flock represent a random sample from the local population.

J. P. Myers

1983-01-01

246

Talk in Blended-Space Speech Communities: An Exploration of Discursive Practices of a Professional Development Group  

ERIC Educational Resources Information Center

This study is an exploration of alternative teacher professional development. While using symbolic interactionism for a research lens, it characterizes the discursive practices commonly found in formal, informal, and blended-space speech communities based on the talk within a leadership-development program comprised of five female, church-based

Garvin, Tabitha Ann

2011-01-01

247

Identifying New Members of Nearby Moving Groups  

NASA Astrophysics Data System (ADS)

Our group has assembled a sample of 14,000 stars of spectral types B9-M9 with measured UVW Galactic space velocities and lying within 125 pc of Earth. We have identified candidate members of three nearby young (less than 100 Myr) moving groups. For stars of spectral types G5 and later, we have used the Kast spectrometer on the Shane 3m telescope at Lick Observatory to measure lithium abundance in order to determine stellar ages. With the data we have obtained from this run, we will be able to establish whether our candidates are bona fide members of the moving groups in question. I will be presenting the preliminary results from this survey, including spectra of the ~50 stars observed thus far. These nearby young stars will make excellent targets for direct imaging followup surveys, since any giant planets around young stars will still be warm, and will therefore be bright enough to detect with instruments like GPI.

Holmbeck, Erika; Vican, Laura

2014-06-01

248

Energy Efficient Cooling Fan for PC Chassis  

Microsoft Academic Search

The energy efficient cooling fan (EnCool Fan) was designed to improve the energy efficiency of the axial cooling fan used in the PC chassis. The EnCool fan has the ability to maintain the same or better heat ventilation rate as compared to ordinary axial cooling fan, and it uses less power. The EnCool fan uses embedded microcontroller with on chip

Rodney H. G. Tan; Y. H. Goh; Y. Q. Wong; V. H. Mok

2009-01-01

249

Virtual Reality at the PC Level  

NASA Technical Reports Server (NTRS)

The main objective of my research has been to incorporate virtual reality at the desktop level; i.e., create virtual reality software that can be run fairly inexpensively on standard PC's. The standard language used for virtual reality on PC's is VRML (Virtual Reality Modeling Language). It is a new language so it is still undergoing a lot of changes. VRML 1.0 came out only a couple years ago and VRML 2.0 came out around last September. VRML is an interpreted language that is run by a web browser plug-in. It is fairly flexible in terms of allowing you to create different shapes and animations. Before this summer, I knew very little about virtual reality and I did not know VRML at all. I learned the VRML language by reading two books and experimenting on a PC. The following topics are presented: CAD to VRML, VRML 1.0 to VRML 2.0, VRML authoring tools, VRML browsers, finding virtual reality applications, the AXAF project, the VRML generator program, web communities and future plans.

Dean, John

1998-01-01

250

A scientific program for infrared, submillimeter and radio astronomy from space: A report by the Management Operations Working Group  

NASA Technical Reports Server (NTRS)

Important and fundamental scientific progress can be attained through space observations in the wavelengths longward of 1 micron. The formation of galaxies, stars, and planets, the origin of quasars and the nature of active galactic nuclei, the large scale structure of the Universe, and the problem of the missing mass, are among the major scientific issues that can be addressed by these observations. Significant advances in many areas of astrophysics can be made over the next 20 years by implementing the outlined program. This program combines large observatories with smaller projects to create an overall scheme that emphasized complementarity and synergy, advanced technology, community support and development, and the training of the next generation of scientists. Key aspects of the program include: the Space Infrared Telescope Facility; the Stratospheric Observatory for Infrared Astronomy; a robust program of small missions; and the creation of the technology base for future major observatories.

1989-01-01

251

Remote facility sharing with ATM networks [PC based ATM Link Delay Simulator (LDS)]. Final report  

SciTech Connect

The ATM Link Delay Simulator (LDS) adds propagation delay to the ATM link on which it is installed, to allow control of link propagation delay in network protocol experiments simulating an adjustable piece of optical fiber. Our LDS simulates a delay of between 1.5 and 500 milliseconds and is built with commodity PC hardware, only the ATM network interface card is not generally available. Our implementation is special in that it preserves the exact spacing of ATM data cells a feature that requires sustained high performance. Our implementation shows that applications demanding sustained high performance are possible on commodity PC hardware. This illustrates the promise that PC hardware has for adaptability to demanding specialized testing of high speed network.

Kung, H. T.

2001-06-01

252

PC 3,4 magnetic pulsations observed simultaneously in the magnetosphere and at multiple ground stations  

NASA Technical Reports Server (NTRS)

Periods of magnetic conjugacy between ISEE and the magnetometer array of the Institute for Geological Sciences have been examined to search for the simultaneous occurrence of Pc 3,4 magnetic pulsations. When compressional waves are seen in space, waves are also observed on the ground at the same frequency and with similar waveforms. The wave amplitude on the ground at midlatitudes is similar to that in space at ISEE but at high latitudes the amplitudes are larger than in space. The one occurrence of a purely transverse signal at ISEE was not observed on the ground. These results confirm that Pc 3,4 wave energy is most readily transported through the magnetosphere by compressional fluctuations.

Odera, T. J.; Van Swol, D.; Russell, C. T.; Green, C. A.

1991-01-01

253

Compact operators and algebraic $K$-theory for groups which act properly and isometrically on Hilbert space.  

E-print Network

We prove the $K$-theoretic Farrell-Jones conjecture for groups as in the title with coefficient rings and $C^*$-algebras which are stable with respect to compact operators. We use this and Higson-Kasparov's result that the Baum-Connes conjecture with coefficients holds for such groups, to show that if $G$ is as in the title then the algebraic and the $C^*$-crossed products of $G$ with a stable $C^*$-algebra have the same $K$-theory.

Guillermo Cortias; Gisela Tartaglia

254

Phosphorylation Negatively Regulates the Function of Coactivator PC4  

Microsoft Academic Search

Human positive cofactor 4 (PC4) mediates activator-dependent transcription by RNA polymerase II, apparently through interactions with transcriptional activators and the basal transcription machinery. We report here that PC4 function is modulated by in vivo phosphorylation. Proteinprotein interaction studies and in vitro transcription assays demonstrate that only the nonphosphorylated form of PC4 is functionally active. Although recombinant PC4 can be phosphorylated

Hui Ge; Yingming Zhao; Brian T. Chait; Robert G. Roeder

1994-01-01

255

Determination of the orbit spaces of non-coregular compact linear groups with one relation among the basic polynomial invariants in the $\\hat P$-matrix approach  

E-print Network

Invariant functions under the transformations of a compact linear group $G$ acting in $\\real^n$ can be expressed in terms of functions defined in the orbit space of $G$. We develop a method to determine the isotropy classes of the orbit spaces of all the real linear groups whose integrity bases (IB) satisfy only one independent relation. The method is tested for IB's formed by 3 (independent) basic invariants. The result is obtained through a metric matrix $\\hat P(p)$, defined only from the scalar products between the gradients of a minimal IB. We determine the matrices $\\wP(p)$ from a universal differential equation, which satisfy new convenient additional conditions, which fit for the non-coregular case. Our results may be relevant in physical contexts where the study of covariant or invariant functions is important, like in the determination of patterns of spontaneous symmetry breaking in quantum field theory, in the analysis of phase spaces and structural phase transitions (Landau's theory), in covariant bifurcation theory, in crystal field theory and so on.

G. Sartori; G. Valente

2000-08-02

256

Draft Genome Sequence of Burkholderia dolosa PC543 Isolated from Cystic Fibrosis Airways.  

PubMed

Burkholderia dolosa is a member of the Burkholderia cepacia complex, a group of opportunistic bacterial pathogens often associated with fatal chronic infections in the lungs of patients suffering from cystic fibrosis (CF). Here, we announce the draft genome sequence of B.dolosa PC543 (LMG 19468), a CF airway isolate. PMID:24526633

Workentine, Matthew L; Surette, Michael G; Bernier, Steve P

2014-01-01

257

www.kansai-airport.or.jp/index.asp www.kate.co.jp/pc/index.html  

E-print Network

10 33 201279 20044 URL www.kansai-airport.or.jp/index.asp URL www.kate.co.jp/pc/index.html MK URL www.mk-group.co.jp/ URL www.yasaka.jp/taxi/shuttle/service.html JASSO JASSO JASSO URL www.jasso.go.jp/exchange/follow.html :0120000530 0570000247

Takada, Shoji

258

www.kansai-airport.or.jp/index.asp www.kate.co.jp/pc/index.html  

E-print Network

10 31 20044 URL www.kansai-airport.or.jp/index.asp URL www.kate.co.jp/pc/index.html MK URL www.mk-group.co.jp/ URL www.yasaka.jp/taxi/shuttle/service.html JASSO JASSO JASSO URL , . ()· . . ( ) () , . , ( ) . , 2004 4 , (:, , ) . . · , . , , . (·) URL www

Takada, Shoji

259

39 CFR 501.16 - PC postage payment methodology.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false PC postage payment methodology. 501.16 Section 501.16 Postal Service UNITED...POSTAGE EVIDENCING SYSTEMS 501.16 PC postage payment methodology. (a) The PC Postage customer is permitted to...

2010-07-01

260

39 CFR 501.16 - PC postage payment methodology.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false PC postage payment methodology. 501.16 Section 501.16 Postal Service UNITED...POSTAGE EVIDENCING SYSTEMS 501.16 PC postage payment methodology. (a) The PC Postage customer is permitted to...

2012-07-01

261

39 CFR 501.16 - PC postage payment methodology.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false PC postage payment methodology. 501.16 Section 501.16 Postal Service UNITED...POSTAGE EVIDENCING SYSTEMS 501.16 PC postage payment methodology. (a) The PC Postage customer is permitted to...

2011-07-01

262

39 CFR 501.16 - PC postage payment methodology.  

...2014-07-01 2014-07-01 false PC postage payment methodology. 501.16 Section 501.16 Postal Service UNITED...POSTAGE EVIDENCING SYSTEMS 501.16 PC postage payment methodology. (a) The PC Postage customer is permitted to...

2014-07-01

263

39 CFR 501.16 - PC postage payment methodology.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false PC postage payment methodology. 501.16 Section 501.16 Postal Service UNITED...POSTAGE EVIDENCING SYSTEMS 501.16 PC postage payment methodology. (a) The PC Postage customer is permitted to...

2013-07-01

264

Zero-temperature real-space renormalization-group method for a Kondo-lattice model Hamiltonian  

Microsoft Academic Search

Details are given of work on a one-dimensional analog of the Kondo-lattice problem, in which a conduction band interacts with a spin in each cell of a lattice. Results of a renormalization-group calculation (generalized from Wilson's approach to the single-site Kondo problem) published earlier in letter form, showed that the system undergoes a second-order crossover transition from an antiferromagnetic state

R. Jullien; J. N. Fields; S. Doniach

1977-01-01

265

PC Software for Artificial Intelligence Applications.  

PubMed

Our review has emphasized that AI tools are programming languages inspired by some problem-solving paradigm. We want to underscore their status as programming languages; even if an AI tool seems to fit a problem perfectly, its proficient use still requires the training and practice associated with any programming language. The programming manuals for PC-Plus, Smalltalk/ V, and Nexpert Object are all tutorial in nature, and the corresponding software packages come with sample applications. We find the manuals to be uniformly good introductions that try to anticipate the problems of a user who is new to the technology. All three vendors offer free technical support by telephone to licensed users. AI tools are sometimes oversold as a way to make programming easy or to avoid it altogether. The truth is that AI tools demand programming-but programming that allows you to concentrate on the essentials of the problem. If we had to implement a diagnostic system, we would look first to a product such as PC-Plus rather than BASIC or C, because PC-Plus is designed specifically for such a problem, whereas these conventional languages are not. If we had to implement a system that required graphical interfaces and could benefit from inheritance, we would look first to an object-oriented system such as Smalltalk/V that provides built-in mechanisms for both. If we had to implement an expert system that called for some mix of AI and conventional techniques, we would look first to a product such as Nexpert Object that integrates various problem-solving technologies. Finally, we might use FORTRAN if we were concerned primarily with programming a well-defined numerical algorithm. AI tools are a valuable complement to traditional languages. PMID:17741465

Epp, H; Kalin, M; Miller, D

1988-05-01

266

Securing your PC and protecting your privacy.  

PubMed

Working in a networked information environment brings new opportunities for getting and sharing information. Regrettably, these benefits of the Internet are challenged by forces that would interfere to satisfy their own profit or malevolent motives. Your networked computer can be infected by viruses, worms, or Trojan horses or infiltrated by spyware, adware, or pop-ups. Without being aware of the dangers and taking precautionary steps, your PC is susceptible to being compromised and your privacy invaded. This column will highlight some of the dangers and offer basic steps for securing your computer and protecting your privacy. PMID:15727543

Schloman, Barbara F

2005-01-01

267

K-theory for the Leaf Spaces of the Orbit Foliations of the co-adjoint Action of some 5-dimensional Solvable Lie groups.  

E-print Network

In this paper, combining Kirillov's method of orbits with Connes' method in Differential Geometry, we study the so-called MD(5,3C)-foliations, i.e. the orbit foliations of the co-adjoint action of MD(5,3C)-groups. First, we classify topologically MD(5,3C)-foliations based on the classification of all MD(5,3C)-algebras in [22] and the picture of co-adjoint orbits (K-orbits) of all MD(5,3C)-groups in [23]. Finally, we study K-theory for leaf space of MD(5,3C)-foliations and describe analytically or characterize Connes' C*-algebras of the considered foliations by KK-functors.

Le Anh Vu; Nguyen Anh Tuan; Duong Quang Hoa

268

Is $J^{PC}=3^{-+}$ molecule possible?  

E-print Network

The confirmation of charged charmonium-like states indiates that heavy quark molecules should exist. We here discuss the possibility of a molecule state with $J^{PC}=3^{-+}$. In a one-boson-exchange model investigation for the S wave $C=+$ $D^*\\bar{D}_2^*$ states, one finds that the strongest attraction is in the case $J=3$ and $I=0$ for both $\\pi$ and $\\sigma$ exchanges. Numerical analysis indicates that this hadronic bound state might exist if a phenomenological cutoff parameter around 2.3 GeV (1.5 GeV) is reasonable with a dipole (monopole) type form factor in the one-pion-exchange model. The cutoff for binding solutions may be reduced to a smaller value once the $\\sigma$ exchange contribution is included. If a state around the $D^*\\bar{D}_2^*$ threshold ($\\approx$4472 MeV) in the channel $J/\\psi\\omega$ (P wave) is observed, the heavy quark spin symmetry implies that it is not a $c\\bar{c}$ meson and the $J^{PC}$ are likely to be $3^{-+}$.

W. Zhu; Yan-Rui Liu; T. Yao

2014-06-04

269

A Parent Communication Group  

ERIC Educational Resources Information Center

The purpose of this communication group is to train parents in the skills of active listening and conflict resolution. The model borrows extensively from Gordon's Parent Effectiveness Training. The parents learn to use communication skills and problem-solving techniques. (Author/PC)

McWhirter, J. Jeffries; Kahn, Sharon E.

1974-01-01

270

Observation of phycoerythrin-containing cyanobacteria and other phytoplankton groups from space using Differential Optical Absorption Spectroscopy on SCIAMACHY data  

NASA Astrophysics Data System (ADS)

In order to understand the marine phytoplankton's role in the global marine ecosystem and biogeochemical cycles it is necessary to derive global information on the distribution of major functional phytoplankton types (PFT) in the world oceans. In our study we use instead of the common ocean color sensors such as CZCS, SeaWiFS, MODIS, MERIS, with rather low spectral resolution, the Differential Optical Absorption Spectroscopy (DOAS) to study the retrieval of phytoplankton distribution and absorption with the satellite sensor Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). SCIAMACHY measures back scattered solar radiation in the UV-Vis-NIR spectral region with a high spectral resolution (0.2 to 1.5 nm). We used in-situ measured phytoplankton absorption spectra from two different RV Polarstern expeditions where different phytoplankton groups were representing or dominating the phytoplankton composition in order to identify these characteristic absorption spectra in SCIAMACHY data in the range of 430 to 500 nm and also to identify absorption from cyanobacterial photosynthetic pigment phycoerythrin. Our results show clearly these absorptions in the SCIAMACHY data. The conversion of these differential absorptions by including the information of the light penetration depth (according to Vountas et al., Ocean Science, 2007) globally distributed pigment concentrations for these characteristic phytoplankton groups for two monthly periods (Feb-March 2004, Oct-Nov 2005 and Oct-Nov 2007) are derived. The satellite retrieved information on cyanobacteria (Synechococcus sp. and Prochlorococcus sp.) and diatoms distribution matches well with the concentration measured from collocated water samples with HPLC technique and also to global model analysis with the NASA Ocean Biogeochemical Model (NOBM from http://reason.gsfc.nasa.gov/OPS/Giovanni/) according to Gregg and Casey 2006 and Gregg 2006. Results are of great importance for global modelling of marine ecosystem and climate change studies regarding changes in the ocean.

Bracher, Astrid; Dinter, Tilman; Burrows, John P.; Vountas, Marco; Rttgers, Rdiger; Peeken, Ilka

271

Remote estimation of phycocyanin (PC) for inland waters coupled with YSI PC fluorescence probe.  

PubMed

Nuisance cyanobacterial blooms degrade water resources through accelerated eutrophication, odor generation, and production of toxins that cause adverse effects on human health. Quick and effective methods for detecting cyanobacterial abundance in drinking water supplies are urgently needed to compliment conventional laboratory methods, which are costly and time consuming. Hyperspectral remote sensing can be an effective approach for rapid assessment of cyanobacterial blooms. Samples (n=250) were collected from five drinking water sources in central Indiana (CIN), USA, and South Australia (SA), which experience nuisance cyanobacterial blooms. In situ hyperspectral data were used to develop models by relating spectral signal with handheld fluorescence probe (YSI 6600 XLM-SV) measured phycocyanin (PC in cell/ml), a proxy pigment unique for indicating the presence of cyanobacteria. Three-band model (TBM), which is effective for chlorophyll-a estimates, was tuned to quantify cyanobacteria coupled with the PC probe measured cyanobacteria. As a comparison, two band model proposed by Simis et al. (Limnol Oceanogr, 50(11): 237-245, 2005; denoted as SM05) was paralleled to evaluate TBM model performance. Our observation revealed a high correlation between measured and estimated PC for SA dataset (R (2)?=0.96; range: 534-20,200 cell/ml) and CIN dataset (R (2)?=0.88; range: 1,300-44,500 cell/ml). The potential of this modeling approach for imagery data were assessed by simulated ESA/Centinel3/OLCI spectra, which also resulted in satisfactory performance with the TBM for both SA dataset (RMSE %?=26.12) and CIN dataset (RMSE %?=34.49). Close relationship between probe-measured PC and laboratory measured cyanobacteria biovolume was observed (R (2)?=0.93, p<0.0001) for the CIN dataset, indicating a stable performance for PC probe. Based on our observation, field spectroscopic measurement coupled with PC probe measurements can provide quantitative cyanobacterial bloom information from both relatively static and flowing inland waters. Hence, it has promising implications for water resource managers to obtain information for early warning detection of cyanobacterial blooms through the close association between probe measured PC values and cyanobacterial biovolume via remote sensing modeling. PMID:23397212

Song, Kaishan; Li, Lin; Tedesco, Lenore; Clercin, Nicole; Hall, Bob; Li, Shuai; Shi, Kun; Liu, Dawei; Sun, Ying

2013-08-01

272

(TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8]/CuPc Two-Component Bilayer Heterojunction-Based Organic Transistors with High Ambipolar Performance.  

PubMed

Organic thin film transistor (OTFT) devices fabricated by the solution-based QLS technique from a mixed (phthalocyaninato)(porphyrinato) europium complex (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] exhibit air-stable ambipolar performance with mobilities of 6.0 10(-5) cm(2) V(-1) s(-)1 for holes and 1.4 10(-4) cm(2) V(-1) s(-1) for electrons, respectively. In good contrast, the two-component bilayer heterojunction thin film devices constructed by directly growing (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] on vacuum deposited (VCD) CuPc film using solution based QLS method were revealed to show unprecedented ambipolar performance with carrier mobilities of 0.16 cm(2) V(-1) s(-1) for holes and 0.30 cm(2) V(-1) s(-1) for electrons. In addition to the intrinsic role of p-type organic semiconductor, the VCD CuPc film on the substrate also acts as a good template that induces significant improvement over the molecular ordering of triple-decker compound in the film. In particular, it results in the change in the aggregation mode of (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] from J-type in the single-layer film to H-type in the bilayer film according to the UV-vis, XRD, and AFM observations. PMID:25599852

Gao, Dameng; Zhang, Xia; Kong, Xia; Chen, Yanli; Jiang, Jianzhuang

2015-02-01

273

The Polycomb group no longer an exclusive club?  

Microsoft Academic Search

Polycomb group (PcG) proteins maintain silencing at target loci in higher eukaryotes but recent evidence suggests that about half of these proteins are also required for maintenance of activation at homeotic loci. We suggest that PcG and trithorax group response elements should acquire a new name, maintenance elements, to reflect the dual function of regulatory elements that bind both groups

Hugh W Brock; Maarten van Lohuizen

2001-01-01

274

Comprehensive Geostatistical Technology on PC Platform  

SciTech Connect

Geostatistics has attracted the attention of many earth scientist and engineers who need better modeling tools for natural gas reservoirs. Two years ago Correlations Company responded to this need through the peer reviewed, DOE Small Business Innovative Research program to develop a fractal algorithm for interpolating between measurements and mapping the consequences. During the two years research period Correlations Company has combined geostatistical modeling with high quality graphics to produce Gviz. This software provides accurate 3D reservoir modeling tools and high quality 3D graphics for PC platforms enabling engineers and geologists to better comprehend reservoirs and consequently improve their decisions. Until recently geostatistical modeling was only available to the limited number of earth scientist familiar with UNIX based platforms. Gviz runs on any PC with Windows 95 or Windows NT operating system. The Gviz pre- processing module reads LAS and ASCII files. The pre-processing module facilitates selection of the stratigraphic units prior to processing by a nearest neighbor, kriging and co-kriging, conditional simulation, or fractal module. A user friendly GUI simplifies the examination of the statistical data and the geostatistical analyses using isotropic and anisotropic variograms. After completing the analyses, the post-processing unit can generate ID models of well logs, 2D models such as cross-sections, or a 3D model of any petrophysical property. Post- processing includes the display of reservoir slices, multiple cross-sections, rotation along any axis, and identification of geobodies (visually inspect the effect of porosity cutoffs on connected pore volume). The post-processor includes an up-scaling module to transform a fine scale grid into a reservoir simulation grid which can then be exported in an Eclipse format. Gviz emphasizes a self-explanatory GUI and visually oriented help pages which guides even a novice through the process of generating realistic, two to five million cell, 3D reservoir models. Beta testing of Gviz will finish in April 1997 and a working version of the PC software package, at one fifth of the cost of a comparable UNIX system, will be available to domestic gas and oil producers in mid-1997.

Stevenson, C.

1997-10-01

275

Architectural implications of hardware-accelerated bucket rendering on the PC  

Microsoft Academic Search

Wrcket rendering is a technique whereby a scene is sorted into screen-space tiles and each tile is rendered independently in turn, We expect hardware-accelerated bucket rendering to become available on the PC, and in this paper we explore the effect of such accelerators on main memory bandwidth, bus bandwidth to the accelerator, and on increased triangle set-up requirements. The most

Michael Cox; Narendra Bhandari

1997-01-01

276

Materials accounting system for an IBM PC  

SciTech Connect

We have adapted the Los Alamos MASS accounting system for use on an IBM PC/AT at the Fuels Manufacturing Facility (FMF) at Argonne National Laboratory-West (ANL-WEST) in Idaho Falls, Idaho. Cost of hardware and proprietary software was less than $10,000 per station. The system consists of three stations between which accounting information is transferred using floppy disks accompanying special nuclear material shipments. The programs were implemented in dBASEIII and were compiled using the proprietary software CLIPPER. Modifications to the inventory can be posted in just a few minutes, and operator/computer interaction is nearly instantaneous. After the records are built by the user, it takes 4 to 5 seconds to post the results to the database files. A version of this system was specially adapted and is currently in use at the FMF facility at Argonne National Laboratory in Idaho Falls. Initial satisfaction is adequate and software and hardware problems are minimal.

Bearse, R.C.; Thomas, R.J.; Henslee, S.P.; Jackson, B.G.; Tracy, D.B.; Pace, D.M.

1986-01-01

277

On the Internet with a PC  

NASA Astrophysics Data System (ADS)

Using a PC to access the Internet and all its services is not difficultonce basic computer hardware, software, and network connections have been installed and configured. Many Internet networking problems can be avoided by contacting network experts before selecting the hardware and network software. This article will introduce some of the hardware, software, and Internet networking options available to the would-be Internet Surfer, and some of the pitfalls that one might encounter. Once the network hardware and software are installed successfully, one can explore the Internet through a number of different software packages that allow the sharing of computer files and printers, as well as logging onto remote host-computers, searching World Wide Web, posting and reading notices on virtually any topic, and sending and receiving electronic mail. This article will describe the functions of several programs that can access these Internet services and how to obtain them.

Woronow, Alex; Dare, Scott

1995-07-01

278

Electrical parameters and gas sensing behaviour of ClInPc thin film devices  

NASA Astrophysics Data System (ADS)

The electrical characteristics of thermally evaporated Chloroindium phthalocyanine thin films (ClInPc) are studied. A number of parameters are evaluated on the basis of the theory of space-charge-limited conduction. ClInPc thin films are extremely stable, in terms of both resistance to chemical attack and thermally, no hysteretic was observed after temperature cycling between room temperature and 500 K. DC current-voltage and current-temperature characteristics were obtained for ClInPc in vacuum and on exposure to dry air (20% O{2}) in both the dark and under illumination with visible light. The conductivity data were analysed in the framework of band theory to elucidate information about the activation energy Eac, forbidden band gap (E_c-E_v), domain or acceptor energy levels (E_e, E_h). In the present work we also examine the response of ClInPc to O{2} and NO{2} at different temperatures.

Azimaraghi, M. E.; Campbell, D.

2008-07-01

279

Braid groups of imprimitive reflection groups  

E-print Network

6/5/2012 1 Braid groups of imprimitive reflection groups Ruth Corran Cap Hornu May 30, 2012 Finite complex reflection groups V a vector space over C with dim(V) = r. A complex reflection s is a non) is the reflection hyperplane for the reflection s A (finite) complex reflection group W is a (finite) group

Digne, François

280

Laboratory and space experiments for the exploration of the interplanetary dust. Memories of the activities of the dust group of the MPI for Nuclear Physics during the years 1964 through 1994  

NASA Astrophysics Data System (ADS)

The dust group in the Max-Planck-Institut fr Kernphysik during its 30 years from 1964 through 1994 largely contributed to the cosmic dust research by the study of microcraters on lunar rocks and of the dust population in the inner solar system with experiments on the 2nd high eccentric orbiting Earth satellite and on the German-American space probe HELIOS. In the 1980s the group has flown successful experiments on the European space agency mission GIOTTO as well as on the soviet space probes Venus Galley to comet Halley. Finally, it was engaged in the laboratory analysis of collected interplanetary dust particles.

Fechtig, Hugo

2001-05-01

281

K-theory for the Leaf Space of Foliations Formed by the Generic K-orbits of a class of Solvable Real Lie Groups.  

E-print Network

The paper is a continuation of the works [17] of Vu and Shum, [18] and [19] of Vu and Hoa. In [17], Vu and Shum classified all the MD5-algebras having commutative derived ideals. In [18], Vu and Hoa considered foliations formed by the maximal dimensional K-orbits (for short, MD5-foliations) of connected MD5-groups such that their Lie algebras have 4-dimensional commutative derived ideals and gave a topological classification of the considered foliations. In [19], Vu and Hoa characterized the Connes' C*-algebras of some MD5-foliations considered in \\cite{VU-HO09} by the method of K-functors. In this paper, we study K-theory for the leaf space of all MD5-foliations which are classified in [18] and characterize the Connes' C*-algebras of them by the method of K-functors.

Anh Vu Le; Quang Hoa Duong; Anh Tuan Nguyen

282

First-principles study for the adsorption of segments of BPA-PC on alpha-Al2O3(0001)  

E-print Network

We have studied the adsorption of bisphenol-A-polycarbonate (BPA-PC) on the alpha-Al2O3(0001) surface using density-functional theory (DFT) with van der Waals (vdW) corrections. The BPA-PC polymer can be divided into its chemical fragments which are phenylene, carbonate and isopropylidene groups. We have calculated the adsorption energy and geometry of the BPA-PC segments that consist of two to three adjacent groups of the polymer. Our DFT results show that the adsorption is dominated by the vdW interaction. It is also important to include the interaction of nearest-neighbor groups in order to provide a realistic environment for the adsorption of the polymer onto the surface. Our results also show that the BPA-PC molecule attaches to the alumina surface via the carbonate group located in the middle of the molecule chain.

Blomqvist, Janne; 10.1103/PhysRevB.84.153410

2011-01-01

283

Software issues for PC-based stereoscopic displays: how to make PC users see stereo  

Microsoft Academic Search

The PC, as the dominant computer platform, is the most exciting market for stereoscopic displays and applications. Several low-cost stereoscopic display systems have been introduced for PCs, including liquid-crystal shutter (LCS) glasses, low-resolution head-mounted displays, and polarized displays with passive polarized glasses. However, each stereoscopic system has its own proprietary driver, and few drivers support Windows. LCDBios, a DOS driver

Donald Sawdai; Gregory J. Hamlin; David Swift

1998-01-01

284

YOUNG STARS NEAR EARTH: THE OCTANS-NEAR ASSOCIATION AND CASTOR MOVING GROUP  

SciTech Connect

All cataloged stellar moving groups and associations with ages ?100 Myr and within 100 pc of Earth have Galactic space motions (UVW) situated in a 'good box' with dimensions ?20 km s{sup 1} on a side. Torres et al. defined the Octans Association as a group of 15 stars with age '20 Myr?' and located ?140 pc from Earth, but with average V space velocity 3.6 km s{sup 1} that is well outside of the good box. We present a list of 14 Hipparcos star systems within 100 pc of Earth that we call {sup O}ctans-Near{sup ;} these systems have UVW similar to those of the much more distant Octans Association. The Octans-Near stars have apparent ages between about 30 and 100 Myr and their relationship to the Octans Association stars is unclear. Six additional star systems have UVW similar to those of Octans-Near stars and likely ages ?200 Myr. These six systems include the late-type binary star EQ Peg6.2 pc from Earth with likely age ?100 Myr and thus likely to be the nearest known pre-main sequence star system. The UVW of stars in a previously proposed ?200 Myr old Castor moving group are not too dissimilar from the UVW of Octans-Near stars. However, stars in the Castor groupif it exists at allare mostly substantially older than 200 Myr and thus generally can readily be distinguished from the much younger Octans-Near stars.

Zuckerman, B.; Vican, Laura [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Song, Inseok [Department of Physics and Astronomy, University of Georgia, Athens, GA 30602-2451 (United States); Schneider, Adam, E-mail: ben@astro.ucla.edu, E-mail: lvican@ucla.edu, E-mail: song@uga.edu, E-mail: Adam.Schneider@Utoledo.edu [Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States)

2013-11-20

285

Identifying wide, cold planets within 8pc  

NASA Astrophysics Data System (ADS)

Direct imaging exoplanet studies have recently unveiled a previously-unexpected population of massive planets (up to 15 M_Jup) in wide orbits (>100AU). Although most of these discoveries have been around younger stars and have been of similar temperatures to field brown dwarfs, one object (WD 0806-661B), is the coldest planet known outside our solar system. We propose a survey of all stars and brown dwarfs within 8pc to identify massive planetary companions in the 150-1500AU separation range. We will 1) Measure the fraction of wide planetary mass companions to stars in the Solar neighbourhood. 2) Identify all planets within 8 parsecs with masses above 8 Jupiter masses in our chosen projected separation range with lower mass limits for closer and younger stars. 3) Identify approximately 8 planets, four of which will have temperatures below 300K making them ideal targets to study water clouds in cold atmospheres with both JWST and the next generation of ground-based extremely large telescopes. Our survey will be the most complete survey for wide planets to-date and will provide both a measurement of the wide planet population and a legacy of cold, well constrained targets for future observatories.

Deacon, Niall; Kraus, Adam; Crossfield, Ian

2014-12-01

286

Role of PrPc Related to Apoptosis  

Microsoft Academic Search

Prion diseases are transmissible neurodegenerative disorders that are invariably fatal in human and animals. Although the nature of the infectious agent and pathogenic mechanisms of prion diseases are not clear, it has been reported to be associated with aberrant metabolism of cellular prion protein (PrPc). In various reports, it has been postulated that PrPc may be involved in programmed cell

Liang J; Lu YY; Wang J; Zhai HH; Yao LP; Ji Q; Guo XY; Liu ZX; Fan D

287

Transforming PC Power Supplies into Smart Car Battery Conditioners  

ERIC Educational Resources Information Center

This paper describes a laboratory project consisting of a PC power supply modification into an intelligent car-battery conditioner with both wireless and wired networking capabilities. Adding a microcontroller to an average PC power supply transforms it into a flexible, intelligent device that can be configured and that is suitable to keep car

Rodriguez-Ascariz, J. M.; Boquete-Vazquez, L.

2011-01-01

288

Cisco JABBER sign in CiscoJABBERQuickReferenceWindows/PC  

E-print Network

Cisco JABBER sign in CiscoJABBERQuickReference­Windows/PC UCSF Cisco JABBER Video Conferencing for Windows/PC Cisco JABBER allows you to make and receive video calls from your laptop or desktop to other UCSF users. (Cisco Movi was rebranded to Cisco JABBER and users who already have a Movi account would

Derisi, Joseph

289

PC-SEAPAK - ANALYSIS OF COASTAL ZONE COLOR SCANNER AND ADVANCED VERY HIGH RESOLUTION RADIOMETER DATA  

NASA Technical Reports Server (NTRS)

PC-SEAPAK is a user-interactive satellite data analysis software package specifically developed for oceanographic research. The program is used to process and interpret data obtained from the Nimbus-7/Coastal Zone Color Scanner (CZCS), and the NOAA Advanced Very High Resolution Radiometer (AVHRR). PC-SEAPAK is a set of independent microcomputer-based image analysis programs that provide the user with a flexible, user-friendly, standardized interface, and facilitates relatively low-cost analysis of oceanographic satellite data. Version 4.0 includes 114 programs. PC-SEAPAK programs are organized into categories which include CZCS and AVHRR level-1 ingest, level-2 analyses, statistical analyses, data extraction, remapping to standard projections, graphics manipulation, image board memory manipulation, hardcopy output support and general utilities. Most programs allow user interaction through menu and command modes and also by the use of a mouse. Most programs also provide for ASCII file generation for further analysis in spreadsheets, graphics packages, etc. The CZCS scanning radiometer aboard the NIMBUS-7 satellite was designed to measure the concentration of photosynthetic pigments and their degradation products in the ocean. AVHRR data is used to compute sea surface temperatures and is supported for the NOAA 6, 7, 8, 9, 10, 11, and 12 satellites. The CZCS operated from November 1978 to June 1986. CZCS data may be obtained free of charge from the CZCS archive at NASA/Goddard Space Flight Center. AVHRR data may be purchased through NOAA's Satellite Data Service Division. Ordering information is included in the PC-SEAPAK documentation. Although PC-SEAPAK was developed on a COMPAQ Deskpro 386/20, it can be run on most 386-compatible computers with an AT bus, EGA controller, Intel 80387 coprocessor, and MS-DOS 3.3 or higher. A Matrox MVP-AT image board with appropriate monitor and cables is also required. Note that the authors have received some reports of incompatibilities between the MVP-AT image board and ZENITH computers. Also, the MVP-AT image board is not necessarily compatible with 486-based systems; users of 486-based systems should consult with Matrox about compatibility concerns. Other PC-SEAPAK requirements include a Microsoft mouse (serial version), 2Mb RAM, and 100Mb hard disk space. For data ingest and backup, 9-track tape, 8mm tape and optical disks are supported and recommended. PC-SEAPAK has been under development since 1988. Version 4.0 was updated in 1992, and is distributed without source code. It is available only as a set of 36 1.2Mb 5.25 inch IBM MS-DOS format diskettes. PC-SEAPAK is a copyrighted product with all copyright vested in the National Aeronautics and Space Administration. Phar Lap's DOS_Extender run-time version is integrated into several of the programs; therefore, the PC-SEAPAK programs may not be duplicated. Three of the distribution diskettes contain DOS_Extender files. One of the distribution diskettes contains Media Cybernetics' HALO88 font files, also licensed by NASA for dissemination but not duplication. IBM is a registered trademark of International Business Machines. MS-DOS is a registered trademark of Microsoft Corporation. HALO88 is a registered trademark of Media Cybernetics, but the product was discontinued in 1991.

Mcclain, C. R.

1994-01-01

290

Biosafety of the plasmid pcDNA3-1E of Eimeria acervulina in chicken.  

PubMed

To evaluate the biosafety of the plasmid pcDNA3-1E of Eimeria acervulina in chicken, two-week-old chickens were injected intramuscularly with the plasmid pcDNA3-1E at dose of 50 ?g/chicken. At the 15 days post-injection, the tissue samples were collected, the total DNA was extracted, and the 3-1E gene was amplified by PCR. Genomic DNA was first purified away from free plasmid using gel electrophoresis, and then assayed for integrated plasmid using PCR amplification of the 3-1E gene. Simultaneously, the environmental dejection samples were collected, the total bacterial DNA was extracted and then transfer of the pcDNA3-1E gene was detected by PCR amplification of the 3-1E gene. Two-week-old chickens were injected intramuscularly with the plasmid pcDNA3-1E with three dosage groups of 100 ?g, 500 ?g and 2500 ?g/chicken for 14 days respectively, and with physiological saline at dose of 2500 ?L/chicken as control group for acute toxicity test. A target band of 583 bp was obtained by PCR with chicken genomic DNA as template. If the chicken genomic DNA was purified, no target band could be obtained. It showed that the recombinant plasmid pcDNA3-1E existed in tissues, and no genomic integration of DNA plasmid was detected in the immunized chickens. No target band was found by PCR with environmental dejection bacteria genomic DNA as template. It showed that integration and transfer phenomenon did not exist in environment. The acute toxicity results showed the typical clinical symptoms did not occur in the inoculated chickens, the blood biochemical indices and viscera configuration were not affected significantly in the inoculated group and control group (P>0.05). The results showed that the plasmid pcDNA3-1E was safe and suitable for chicken clinical trials. PMID:23247194

Zhao, Yuelan; Bao, Yongzhan; Zhang, Lijuan; Chang, Liyun; Jiang, Lufeng; Liu, Yiwei; Zhang, Lei; Qin, Jianhua

2013-03-01

291

PcG Proteins, DNA Methylation, and Gene Repression by Chromatin Looping  

Microsoft Academic Search

Many DNA hypermethylated and epigenetically silenced genes in adult cancers are Polycomb group (PcG) marked in embryonic stem (ES) cells. We show that a large region upstream (?30 kb) of and extending ?60 kb around one such gene, GATA-4, is organizedin Tera-2 undifferentiated embryonic carcinoma (EC) cellsin a topologically complex multi-loop conformation that is formed by multiple internal long-range contact

Vijay K Tiwari; Kelly M McGarvey; Julien D. F Licchesi; Joyce E Ohm; James G Herman; Dirk Schbeler; Stephen B Baylin

2008-01-01

292

www.kansai-airport.or.jp/index.asp www.kate.co.jp/pc/index.html  

E-print Network

10 31 20044 URL www.kansai-airport.or.jp/index.asp URL www.kate.co.jp/pc/index.html MK URL www.mk-group.co.jp/ URL www.yasaka.jp/taxi/shuttle/service.html JASSO JASSO JASSO URL-20-8762 9:00 ­ 15:00 9:00 ­ 16:00 #12;10 32 10 () 20044 URL www

Takada, Shoji

293

SUSY `99 P.C. Bhat June 1419, 1999 Prospects for  

E-print Network

National Accelerator Laboratory for The Fermilab Run 2 Higgs Working Group #12; SUSY `99 P.C. Bhat June 14­Tag Efficiency b­Tag Efficiency b­Tag Efficiency SHW b tagging efficiency: Alternative tight/loose scheme: tight loose b c u/d/s E T of jets (GeV) Tag efficiency 0 0.25 0.5 0.75 1 20 30 40 50 60 70 80 90 100 SHW b

Bhat, Pushpalatha

294

Exacerbation of experimental autoimmune encephalomyelitis in prion protein (PrPc)-null mice: evidence for a critical role of the central nervous system  

PubMed Central

Background The cellular prion protein (PrPc) is a host-encoded glycoprotein whose transconformation into PrP scrapie (PrPSc) initiates prion diseases. The role of PrPc in health is still obscure, but many candidate functions have been attributed to the protein, both in the immune and the nervous systems. Recent data show that experimental autoimmune encephalomyelitis (EAE) is worsened in mice lacking PrPc. Disease exacerbation has been attributed to T cells that would differentiate into more aggressive effectors when deprived of PrPc. However, alternative interpretations such as reduced resistance of neurons to autoimmune insult and exacerbated gliosis leading to neuronal deficits were not considered. Method To better discriminate the contribution of immune cells versus neural cells, reciprocal bone marrow chimeras with differential expression of PrPc in the lymphoid or in the central nervous system (CNS) were generated. Mice were subsequently challenged with MOG35-55 peptide and clinical disease as well as histopathology were compared in both groups. Furthermore, to test directly the T cell hypothesis, we compared the encephalitogenicity of adoptively transferred PrPc-deficient versus PrPc-sufficient, anti-MOG T cells. Results First, EAE exacerbation in PrPc-deficient mice was confirmed. Irradiation exacerbated EAE in all the chimeras and controls, but disease was more severe in mice with a PrPc-deleted CNS and a normal immune system than in the reciprocal construction. Moreover, there was no indication that anti-MOG responses were different in PrPc-sufficient and PrPc-deficient mice. Paradoxically, PrPc-deficient anti-MOG 2D2 T cells were less pathogenic than PrPc-expressing 2D2 T cells. Conclusions In view of the present data, it can be concluded that the origin of EAE exacerbation in PrPc-ablated mice resides in the absence of the prion protein in the CNS. Furthermore, the absence of PrPc on both neural and immune cells does not synergize for disease worsening. These conclusions highlight the critical role of PrPc in maintaining the integrity of the CNS in situations of stress, especially during a neuroinflammatory insult. PMID:22281016

2012-01-01

295

Virtual Reality Today on a PC.  

ERIC Educational Resources Information Center

Describes a microcomputer-based digital video course that uses virtual reality to teach the code inspection (i.e., formal software technical review) process. Use of virtual reality for group process activities that involve interpersonal and group dynamic skills is discussed, and research indicating that realism improves course effectiveness is

Christel, Michael

1992-01-01

296

Propulsion stability codes for liquid propellant propulsion systems developed for use on a PC computer  

NASA Technical Reports Server (NTRS)

Research into component modeling and system synthesis leading to the analysis of the major types of propulsion system instabilities and the characterization of various components characteristics are presented. Last year, several programs designed to run on a PC were developed for Marshall Space Flight Center. These codes covered the low, intermediate, and high frequency modes of oscillation of a liquid rocket propulsion system. No graphics were built into these programs and only simple piping layouts were supported. This year's effort was to add run time graphics to the low and intermediate frequency codes, allow new types of piping elements (accumulators, pumps, and split pipes) in the low frequency code, and develop a new code for the PC to generate Nyquist plots.

Doane, George B., III; Armstrong, Wilbur C.

1991-01-01

297

PC4CAST: A tool for DSN load forecasting and capacity planning  

NASA Technical Reports Server (NTRS)

Effectively planning the use and evolution of the Deep Space Network (DSN) is a complex problem involving many parameters. The tool that models many of these complexities, yet requires simple structured inputs and provides concise easy-to-understand metrics to aid in the planning process is discussed. The tool, PC4CAST, is used for both load forecasting (predicting how well planned that DSN resources meet expected demand) and as a decision support tool in the capacity-planning process (determining the relative benefits of capacity expansion options). It is now in use in the TDA Planning Office, has been used in numerous studies, and is also being used by the JPL Multimission Operations System Office (MOSO) as an integral part of Resource Allocation Team activities. Experience using the tool has helped to identify additional requirements that will further improve the planning process, which can be met by future PC4CAST versions.

Loyola, S. J.

1993-01-01

298

Combined treatment of PC-3 cells with ultrasound and microbubbles suppresses invasion and migration  

PubMed Central

The aim of the present study was to investigate whether ultrasound treatment combined with microbubbles inhibits cell invasion and migration in androgen-independent prostate cancer (PCa) cells and to identify the probable mechanism. Ultrasound was used in continuous wave mode at a frequency of 21 kHz and with a spatial-average temporal-average intensity of 46 mW/cm2. Ultrasound combined with microbubbles (200 ?l; SonoVue) was administered to androgen-independent human PCa PC-3 cells for 30 sec. The PC-3 cells were divided into three groups: The control group, the ultrasound group (US) and the ultrasound combined with microbubbles group (US + MB). Following treatment for 12, 24, 48 and 72 h, cell counting kit-8 was used to assess cell viability. Cell invasion and migration was measured 12 h after treatment using Transwell migration assays. Quantitative polymerase chain reaction and western blot analysis were used to evaluate the expression of the migration-associated proteins, matrix metalloproteinase (MMP)-2 and MMP-9. Cell reproduction levels in the US and US + MB groups were significantly suppressed when compared with the control group (P<0.01) following 24 h of treatment and this suppression was significantly higher in the US + MB group than in the US group (P<0.01). However, no significant differences in cell reproduction levels between the three groups were identified at 12 h (P>0.05). Ultrasound combined with microbubbles significantly suppressed the level of invasion and migration in the PC-3 cells compared with the control group (190.8314.63 vs. 509.6718.62, P<0.01; and 86.6710.60 vs. 271.3365.14; P<0.01, respectively). Furthermore, combined treatment with ultrasound and microbubbles suppressed the expression of MMP-2 and MMP-9. In conclusion, it was found that ultrasound combined with microbubbles suppressed invasion and migration in human PCa PC-3 cells via downregulation of MMP-2 and MMP-9. PMID:25120726

WEI, CONG; BAI, WEN-KUN; WANG, YU; HU, BING

2014-01-01

299

Spectral characteristics of Pc 3 and Pc 4/5 magnetic pulsation bands observed near L = 6  

NASA Technical Reports Server (NTRS)

The relationships among Pc 3, Pc 4, and Pc 5 activities observed at ground stations near L = 6 are clarified by comparing their dynamic spectral structures. It is found that there are two predominant spectral bands throughout the daytime with frequencies of about 20-80 mHz and about 3-10 mHz. At synchronous orbit, corresponding spectral bands are seen in the frequency-time spectra of the azimuthal component which generally show a clear harmonic structure when the satellite is located at the off-magnetic equator. The result strongly suggests that the 20-80 mHz band is the higher harmonics of standing shear Alfven waves and the 3-10 mHz band is the fundamental mode. Switching of activity between both bands is frequently observed on magnetically quiet days, indicating that the Pc 3 and Pc 4/5 bands are excited by different external driving sources.

Tonegawa, Y.; Fukunishi, H.; Hirasawa, T.; Mcpherron, R. L.; Sakurai, T.; Kato, Y.

1984-01-01

300

November 1988 IBM PC MST MONITOR SYSTEM  

E-print Network

a description of the MST monitor system. Section II describes the diagnostic sensors, section III describes current feed 5. Flux loop encircling the main poloidal iron core 6. Current shunt in the poloidal space is available outside for the Rogowskii loop, and having it inside allows one to detect arcs

Sprott, Julien Clinton

301

Conservation of the prohormone convertase gene family in metazoa: analysis of cDNAs encoding a PC3-like protein from hydra.  

PubMed Central

A subclass of proteolytic enzymes that correctly cleave precursor proteins at paired basic residues and are structurally related to the bacterial subtilisins has recently been identified. In yeast, a single membrane-bound proteolytic processing enzyme encoded by the kex2 gene has been found, whereas in higher vertebrates cDNAs encoding four distinct enzymes (PC2, PC3, furin, and PACE 4) have been identified. Like kex2, furin (also known as PACE) contains a hydrophobic transmembrane domain, but PC2, PC3, and PACE 4 lack this feature. All five enzymes exhibit striking similarities in their catalytic domains, and this suggests that they have arisen from a common ancestral subtilisin-like gene. We report here the identification of cDNAs encoding a protein that is similar in structure to PC3 from a simple metazoan, Hydra vulgaris (formerly Hydra attenuata). cDNAs encoding two isoforms of this PC3-like enzyme were obtained that differ only in their carboxyl-terminal sequences, probably due to alternative splicing of a common pre-mRNA. Neither form contains a transmembrane domain. Predicted amino acid sequence comparisons revealed that the hydra PC3-like enzyme is 55.4% and 56.7% identical in the catalytic domain to mouse PC3 and human furin, respectively. RNA blot analyses revealed that the PC3-like RNA is expressed predominantly in the hydra body column and not in the head region, although the hydra head contains a high density of nerve cells, which synthesize a variety of neuropeptides. For this reason, we suspect that another proprotein cleavage enzyme isoform may be expressed in head nerve cells. The isolation of a PC3-like cDNA from hydra is consistent with the presence of neuroendocrine cells and indicates that the PC/furin gene family has been well conserved in all metazoa. A simplified nomenclature for the group of mammalian processing proteases is proposed. Images PMID:1495957

Chan, S J; Oliva, A A; LaMendola, J; Grens, A; Bode, H; Steiner, D F

1992-01-01

302

Solid state coordination chemistry: temperature dependence of the crystal chemistry of the oxovanadium-phenylphosphonate-copper(II)-2,2'-bipyridine system. Crystal structures of the one-dimensional [{Cu(bpy)}VO 2(O 3PC 6H 5)(HO 3PC 6H 5)], [{Cu 3(bpy) 3(H 2O)}V 4O 9(O 3PC 6H 5) 4], [{Cu(bpy)} 2V 3O 6(O 3PC 6H 5) 3(HO 3PC 6H 5)] and [{Cu(bpy)}VO(O 3PC 6H 5) 2  

NASA Astrophysics Data System (ADS)

The temperature dependence of the hydrothermal chemistry of the oxovanadium-phenylphosphonate/copper(II)-bipyridine system has been investigated. Reactions of identical compositions of CuSO 4?5H 2O, bipyridine, C 6H 5PO 3H 2 and Na 3VO 4 in H 2O yielded [{Cu(bpy)}VO 2(O 3PC 6H 5)(HOC 6H 5)] ( 1), [{Cu 3(bpy) 3(H 2O)}V 4O 9(O 3PC 6H 5) 4]?3.9H 2O ( 2?3.9H 2O) and [{Cu(bpy)}VO(O 3PC 6H 5) 2] ( 4) at 120 C, 150 C and 180-230 C, respectively. Furthermore, variations in stoichiometry at 150 C provided yet a fourth one-dimensional phase [{Cu(bpy)} 2V 3O 6(O 3PC 6H 5) 3(HO 3PC 6H 5)] ( 3). Substitution of a methyl substituent for the phenyl group yielded another one-dimensional material [{Cu(bpy)}V 2O 4(O 3PCH 3) 2?H 2O ( 5?H 2O). The structural chemistry is discussed in terms of the polyhedral variability of vanadium oxides, the tendency of oxovanadium polyhedra to form oligomeric arrays, the variable modes of polyhedral connectivity associated with vanadium square pyramids and phosphorus tetrahedra and the steric influences of the copper(II)-bpy subunit.

Yucesan, Gundog; Ouellette, Wayne; Golub, Vladimir; O'Connor, Charles J.; Zubieta, Jon

2005-04-01

303

Effects of extremely low frequency magnetic fields on NGF induced neuronal differentiation of PC12 cells.  

PubMed

Extremely low-frequency magnetic fields (ELF-MFs) affect various cellular processes and systems, such as cell proliferation, differentiation and metabolic pathways. The present study investigated ELF-MFs effect on nerve growth factor (NGF) induced neuronal differentiation of PC12 cells using proteomic applications to understand its role in the enhancement of neuronal differentiation. After 50?Hz, 1?mT ELF-MFs 5-day exposure on NGF induced PC12 cells, it was observed to increase neurite length as well as an increase in the number of neurite bearing cells. It was also discovered that there was a decrease in proliferation activity, which is associated with an increase in differentiated cells. Neuronal differentiation related mRNA levels and protein levels were increased in NGF induced PC12 cells. Compared with NGF induced group, ELF-MFs stimulated PC12 cells had different protein expression as measured with two-dimensional electrophoresis (2-DE) gels. Consequently six differentially expressed spots were detected between the 2-DE maps, which were identified by electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-Q-TOF LC/MS/MS) as: peripherin, neurosecretory protein nerve growth factor inducible (VGF8a) precursor, dnaK-type molecular chaperone sp72-ps1 (HSP72-psI), low molecular weight (Mr) phosphotyrosine protein phosphatase isoenzyme AcP1 (LMW-PTP/ACP1), Tubulin alpha-1A (TUBA1A) chain, outcome predictor in acute leukemia 1 homolog (OPA1L). The identification of these proteins provides clues to the mechanism of ELF-MFs stimulation on NGF induced PC12 cells that occur during neuronal differentiation and may contribute to the development novel treatments for neurodegenerative diseases. PMID:25159695

Jung, In-Soo; Kim, Hyun-Jung; Noh, Ran; Kim, Soo-Chan; Kim, Chan-Wha

2014-10-01

304

Photodynamic Therapy with the Phthalocyanine Photosensitizer Pc 4  

PubMed Central

Photodynamic therapy (PDT) is emerging as a promising non-invasive treatment for cancers. PDT involves either local or systemic administration of a photosensitizing drug, which preferentially localizes within the tumor, followed by illumination of the involved organ with light, usually from a laser source. Here, we provide a selective overview of our experience with PDT at Case Western Reserve University, specifically with the silicon phthalocyanine photosensitizer Pc 4. We first review our in-vitro studies evaluating the mechanism of cell killing by Pc 4-PDT. Then we briefly describe our clinical experience in a Phase I trial of Pc 4-PDT and our preliminary translational studies evaluating the mechanisms behind tumor responses. Preclinical work identified (a) cardiolipin and the anti-apoptotic proteins Bcl-2 and Bcl-xL as targets of Pc 4-PDT, (b) the intrinsic pathway of apoptosis, with the key participation of caspase-3, as a central response of many human cancer cells to Pc 4-PDT, (c) signaling pathways that could modify apoptosis, and (d) a formulation by which Pc 4 could be applied topically to human skin and penetrate at least through the basal layer of the epidermis. Clinical-translational studies enabled us to develop an immunohistochemical assay for caspase-3 activation, using biopsies from patients treated with topical Pc 4 in a Phase I PDT trial for cutaneous T-cell lymphoma. Results suggest that this assay may be used as an early biomarker of clinical response. PMID:17397888

Miller, Janine D.; Baron, Elma D.; Scull, Heather; Hsia, Andrew; Berlin, Jeffrey C.; McCormick, Thomas; Colussi, Valdir; Kenney, Malcolm E.; Cooper, Kevin D.; Oleinick, Nancy L.

2007-01-01

305

ISTUM PC: industrial sector technology use model for the IBM-PC  

SciTech Connect

A project to improve and enhance the Industrial Sector Technology Use Model (ISTUM) was originated in the summer of 1983. The project had dix identifiable objectives: update the data base; improve run-time efficiency; revise the reference base case; conduct case studies; provide technical and promotional seminars; and organize a service bureau. This interim report describes which of these objectives have been met and which tasks remain to be completed. The most dramatic achievement has been in the area of run-time efficiency. From a model that required a large proportion of the total resources of a mainframe computer and a great deal of effort to operate, the current version of the model (ISTUM-PC) runs on an IBM Personal Computer. The reorganization required for the model to run on a PC has additional advantages: the modular programs are somewhat easier to understand and the data base is more accessible and easier to use. A simple description of the logic of the model is given in this report. To generate the necessary funds for completion of the model, a multiclient project is proposed. This project will extend the industry coverage to all the industrial sectors, including the construction of process flow models for chemicals and petroleum refining. The project will also calibrate this model to historical data and construct a base case and alternative scenarios. The model will be delivered to clients and training provided. 2 references, 4 figures, 3 tables.

Roop, J.M.; Kaplan, D.T.

1984-09-01

306

The Australian experience with the PC-EVN recorder  

NASA Astrophysics Data System (ADS)

We report on our experiences using the Metshovi Radio Observatory's (MRO) VLBI Standard Interface (VSI, Whitney 2002) recorder in a number of astronomical applications. The PC-EVN device is a direct memory access (DMA) interface which allows 512 megabit per second (Mbps) or better recording to ``off the shelf'' PC components. We have used this setup to record at 640 Mbps for a pulsar coherent dispersion system and at 256 Mpbs for a global VLBI session. We have also demonstrated recording at 512 Mbps and will shortly form cross correlations between the CPSR-II and the PC-EVN systems. (astro-ph/0412685)

Dodson, R.; Tingay, S.; West, C.; Phillips, C.; Tzioumis, A. K.; Ritakari, J.; Briggs, F.

307

A metric space for Type Ia supernova spectra  

NASA Astrophysics Data System (ADS)

We develop a new framework for use in exploring Type Ia supernovae (SNe Ia) spectra. Combining principal component analysis (PCA) and partial least square (PLS) analysis we are able to establish correlations between the principal components (PCs) and spectroscopic/photometric SNe Ia features. The technique was applied to 120 SN and 800 spectra from the Nearby Supernova Factory. The ability of PCA to group together SNe Ia with similar spectral features, already explored in previous studies, is greatly enhanced by two important modifications: (1) the initial data matrix is built using derivatives of spectra over the wavelength, which increases the weight of weak lines and discards extinction, and (2) we extract time evolution information through the use of entire spectral sequences concatenated in each line of the input data matrix. These allow us to define a stable PC parameter space which can be used to characterize synthetic SN Ia spectra by means of real SN features. Using PLS, we demonstrate that the information from important previously known spectral indicators (namely the pseudo-equivalent width of Si II 5972 /Si II 6355 and the line velocity of S II 5640 /Si II 6355 ) at a given epoch is contained within the PC space and can be determined through a linear combination of the most important PCs. We also show that the PC space encompasses photometric features like B/V magnitudes, B - V colours and SALT2 parameters c and x1. The observed colours and magnitudes, which are heavily affected by extinction, cannot be reconstructed using this technique alone. All the above-mentioned applications allowed us to construct a metric space for comparing synthetic SN Ia spectra with observations.

Sasdelli, Michele; Hillebrandt, W.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Benitez-Herrera, S.; Bongard, S.; Buton, C.; Canto, A.; Cellier-Holzem, F.; Chen, J.; Childress, M.; Chotard, N.; Copin, Y.; Fakhouri, H. K.; Feindt, U.; Fink, M.; Fleury, M.; Fouchez, D.; Gangler, E.; Guy, J.; Ishida, E. E. O.; Kim, A. G.; Kowalski, M.; Kromer, M.; Lombardo, S.; Mazzali, P. A.; Nordin, J.; Pain, R.; Pcontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigault, M.; Runge, K.; Saunders, C.; Scalzo, R.; Smadja, G.; Suzuki, N.; Tao, C.; Taubenberger, S.; Thomas, R. C.; Tilquin, A.; Weaver, B. A.

2015-02-01

308

Near-equatorial Pi2 and Pc3 waves observed by CHAMP and on SAMBA/MAGDAS stations  

NASA Astrophysics Data System (ADS)

We have examined simultaneous ULF activity in the Pi2 and Pc3 bands at the near-equatorial magnetic stations in South America from SAMBA and MAGDAS arrays and low-orbiting CHAMP satellite during its passage over this meridional network. At the nighttime, both Pi2 and Pc3 waves in the upper ionosphere and on the ground are nearly of the same magnitude and in-phase. At the same time, the daytime Pc3 pulsations on the ground and in space are nearly out-of-phase. Comparison of observational results with the theoretical notions on the MHD wave interaction with the system ionosphere-atmosphere-ground suggests that nighttime low-latitude Pi2 and Pc3 wave signatures are produced by magnetospheric fast compressional mode. The daytime near-equatorial Pc3 waves still resist a quantative interpretation. These waves may be produced by a combination of two mechanisms: compressional mode leakage through the ionosphere, and by oscillatory ionospheric current spreading towards equatorial latitudes.

Cuturrufo, F.; Pilipenko, V.; Heilig, B.; Stepanova, M.; Lhr, H.; Vega, P.; Yoshikawa, A.

2015-02-01

309

Abnormal expression and processing of the proprotein convertases PC1 and PC2 in human colorectal liver metastases  

PubMed Central

Background The family of proprotein convertases has been recently implicated in tumorigenesis and metastasis in animal models. However, these studies have not yet been completely corroborated in human tumors. Methods Using RT PCR, immunoblot and immunohistochemistry we assessed the presence and the processing patterns of the convertases PC1 and PC2 as well as the PC2 specific chaperone 7B2 in human liver metastases originating from colorectal cancer and compared them to unaffected and normal liver. Furthermore, we assessed the presence and processing profiles of PC1, PC2 and 7B2 in primary colon cancers. Results mRNA, protein expression, and protein cleavage profiles of proprotein convertases 1 and 2 are altered in liver colorectal metastasis, compared to unaffected and normal liver. Active PC1 protein is overexpressed in tumor, correlating with its mRNA profile. Moreover, the enhanced PC2 processing pattern in tumor correlates with the overexpression of its specific binding protein 7B2. These results were corroborated by immunohistochemistry. The specific and uniform convertase pattern observed in the metastases was present only in a fraction of primary colon cancers. Conclusion The uniformly altered proprotein convertase profile in liver metastases is observed only in a fraction of primary colon cancers, suggesting possible selection processes involving PCs during metastasis as well as an active role of PCs in liver metastasis. In addition, the exclusive presence of 7B2 in metastatic tumors may represent a new target for early diagnosis, prognosis and/or treatment. PMID:16293189

Tzimas, George N; Chevet, Eric; Jenna, Sarah; Nguyn, Duc Thang; Khatib, Abdel M; Marcus, Victoria; Zhang, Yi; Chrtien, Michel; Seidah, Nabil; Metrakos, Peter

2005-01-01

310

PC BEEPOP - AN ECTOXICOLOGICAL SIMULATION MODEL FOR HONEY BEE POPULATIONS  

EPA Science Inventory

PC BEEPOP is a computer model that simulates honey bee colony population dynamics. he model consists of a feedback system of interdependent elements, including colony condition, environmental variability, and contaminant exposures. t includes a mortality module (BEEKILL) and a ch...

311

Single-event upset in advanced PowerPC microprocessors  

NASA Technical Reports Server (NTRS)

Proton and heavy-ion single-event upset susceptibility has been measured for the MotorolaPowerPC7400. The results show that this advanced device has low upset susceptibility, despite the scaling and design advances.

Irom, F.; Swift, G. M.; Farmanesh, F.; Millward, D. G.

2002-01-01

312

Pre-engagement process improvement in IBM PC services  

E-print Network

The front end of the IBM PC factory integration & deployment process is a pre-engagement process. In this study, the pre-engagement process, was analyzed. The organizational structure in the pre-engagement process and the ...

Zuo, Jie, M. Eng. Massachusetts Institute of Technology

2007-01-01

313

Improving the flexibility of the desktop PC supply chain  

E-print Network

Dell Inc. is a company headquartered in Round Rock, TX founded by entrepreneur Michael Dell in 1984. In its 20+ years of history, Dell has revolutionized the PC industry by deploying the "Dell Direct" model--eliminating ...

Wu, Johnson (Johnson Chun Hsien)

2006-01-01

314

Endoproteolytic processing of integrin pro-alpha subunits involves the redundant function of furin and proprotein convertase (PC) 5A, but not paired basic amino acid converting enzyme (PACE) 4, PC5B or PC7.  

PubMed

Several integrin alpha subunits undergo post-translational endoproteolytic processing at pairs of basic amino acids that is mediated by the proprotein convertase furin. Here we ask whether other convertase family members can participate in these processing events. We therefore examined the endoproteolysis rate of the integrin subunits pro-alpha5, alpha6 and alphav by recombinant furin, proprotein convertase (PC)5A, paired basic amino acid converting enzyme (PACE)4, PC1, PC2 and PC7 in vitro and/or ex vivo after overexpression in LoVo cells that were deficient in furin activity. We found that 60-fold more PC1 than furin was needed to produce 50% cleavage of pro-alpha subunit substrates in vitro; the defective pro-alpha chain endoproteolysis in LoVo cells was not rescued by overexpression of PC1 or PC2. No endoproteolysis occurred with PC7 either in vitro or ex vivo, although similar primary sequences of the cleavage site are found in integrins and in proteins efficiently processed by PC7, which suggests that a particular conformation of the cleavage site is required for optimal convertase-substrate interactions. In vitro, 50% cleavage of pro-alpha subunits was obtained with one-third of the amount of PC5A and PACE4 than of furin. In LoVo cells, PC5A remained more active than furin, PACE4 activity was quite low, and PC5B, which differs from PC5A by a C-terminal extension containing a transmembrane domain, was very inefficient in processing integrin alpha-subunit precursors. In conclusion, these results indicate that integrin alpha-subunit endoproteolytic processing involves the redundant function of furin and PC5A and to a smaller extent PACE4, but not of PC1, PC2, PC5B or PC7. PMID:10657249

Lissitzky, J C; Luis, J; Munzer, J S; Benjannet, S; Parat, F; Chrtien, M; Marvaldi, J; Seidah, N G

2000-02-15

315

Endoproteolytic processing of integrin pro-alpha subunits involves the redundant function of furin and proprotein convertase (PC) 5A, but not paired basic amino acid converting enzyme (PACE) 4, PC5B or PC7.  

PubMed Central

Several integrin alpha subunits undergo post-translational endoproteolytic processing at pairs of basic amino acids that is mediated by the proprotein convertase furin. Here we ask whether other convertase family members can participate in these processing events. We therefore examined the endoproteolysis rate of the integrin subunits pro-alpha5, alpha6 and alphav by recombinant furin, proprotein convertase (PC)5A, paired basic amino acid converting enzyme (PACE)4, PC1, PC2 and PC7 in vitro and/or ex vivo after overexpression in LoVo cells that were deficient in furin activity. We found that 60-fold more PC1 than furin was needed to produce 50% cleavage of pro-alpha subunit substrates in vitro; the defective pro-alpha chain endoproteolysis in LoVo cells was not rescued by overexpression of PC1 or PC2. No endoproteolysis occurred with PC7 either in vitro or ex vivo, although similar primary sequences of the cleavage site are found in integrins and in proteins efficiently processed by PC7, which suggests that a particular conformation of the cleavage site is required for optimal convertase-substrate interactions. In vitro, 50% cleavage of pro-alpha subunits was obtained with one-third of the amount of PC5A and PACE4 than of furin. In LoVo cells, PC5A remained more active than furin, PACE4 activity was quite low, and PC5B, which differs from PC5A by a C-terminal extension containing a transmembrane domain, was very inefficient in processing integrin alpha-subunit precursors. In conclusion, these results indicate that integrin alpha-subunit endoproteolytic processing involves the redundant function of furin and PC5A and to a smaller extent PACE4, but not of PC1, PC2, PC5B or PC7. PMID:10657249

Lissitzky, J C; Luis, J; Munzer, J S; Benjannet, S; Parat, F; Chrtien, M; Marvaldi, J; Seidah, N G

2000-01-01

316

Pc5 micropulsation power at conjugate high-latitude locations  

Microsoft Academic Search

The micropulsation power, integrated over the Pc5 frequency range, has been calculated for the horizontal component of the geomagnetic field at two high-latitude conjugate locations: Dumont D'Urville (corrected geomagnetic coordinates: 80.61S, 235.76E) and Mould Bay (corrected geomagnetic coordinates: 80.85N, 272.65E). Because of the different distances between the geographic and the geomagnetic poles in each hemisphere, the comparison between the Pc5

Paola Ballatore

2003-01-01

317

Information Retrieval on an SCI-Based PC Cluster  

Microsoft Academic Search

This article presents an efficient parallel information retrieval (IR) system which provides fast information service for the Internet users on low-cost high-performance PC-NOW environment. The IR system is implemented on a PC cluster based on the scalable coherent interface (SCI), a powerful interconnecting mechanism for both shared memory models and message-passing models. In the IR system, the inverted-index file (IIF)

Sang-Hwa Chung; Hyuk-Chul Kwon; Kwang Ryel Ryu; Yoojin Chung; Hankook Jang; Cham-Ah Choi

2001-01-01

318

Real time network simulation with PC-cluster  

Microsoft Academic Search

This paper presents a new architecture layout for a real-time power system simulator based on a distributed cluster of IBM PC-compatible desktop computers. A real-time network simulator based on a PC cluster can successfully cope with the size requirements of growing power systems and the computational demands of fast transient studies. A powerful product has been developed using off-the-shelf Pentium

Jorge Ariel Hollman; Jos Ramn Mart

2003-01-01

319

Wf/pc Cycle 1 Calibration: Rapid Internal Monitor  

NASA Astrophysics Data System (ADS)

This test is to take repeated internal flats to test for contamination buildup on the optical surfaces or the reappearance of QEH. Part 1: INTFLATS in F555W are obtained every 4 days in both WFC and PC to check for measles or daisies and to monitor scattered light. Part 2: Sequential INTFLATS in F439W with PC are obtained every 7 days to check for QEH.

MacKenty, John

1990-12-01

320

Wf/pc Cycle 3 Calibration: Rapid Internal Monitor  

NASA Astrophysics Data System (ADS)

This test is to take repeated internal flats to test for contamination buildup on the optical surfaces or the reappearance of QEH. Part 1: INTFLATS in F555W are obtained every 4 days in both WFC and PC to check for measles or daisies and to monitor scattered light. Part 2: Sequential INTFLATS in F439W with PC are obtained every 7 days to check for QEH.

MacKenty, John

1992-06-01

321

Wf/pc Cycle 2 Calibration: Rapid Internal Monitor  

NASA Astrophysics Data System (ADS)

This test is to take repeated internal flats to test for contamination buildup on the optical surfaces or the reappearance of QEH. Part 1: INTFLATS in F555W are obtained every 4 days in both WFC and PC to check for measles or daisies and to monitor scattered light. Part 2: Sequential INTFLATS in F439W with PC are obtained every 7 days to check for QEH.

MacKenty, John

1991-07-01

322

for:PC3124M M.POSTRANECKY  

E-print Network

KITTING LIST for:PC3124M OM Job No: April 14, 1999 Page 1 of 3 Engineer Designer PC Issue Circuit EPC.00.250.DTM LEMO RT­ANGLE SOCKET SIZE 00, PCB MOUNT 8 ­ J11 LEMO EPG.302.HLN LEMO SOCKET, 2 FEMALE PCB MOUNT 1 ­ J12­15 3M 3793­5302 10WAY RT­ANG IDC HEADER, CLASS II 4 ­ J16 3M 2510­6002 10WAY

University College London

323

Planetary data analysis and display system: A version of PC-McIDAS  

NASA Technical Reports Server (NTRS)

We propose to develop a system for access and analysis of planetary data from past and future space missions based on an existing system, the PC-McIDAS workstation. This system is now in use in the atmospheric science community for access to meteorological satellite and conventional weather data. The proposed system would be usable not only by planetary atmospheric researchers but also by the planetary geologic community. By providing the critical tools of an efficient system architecture, newer applications and customized user interfaces can be added by the end user within such a system.

Limaye, Sanjay S.; Sromovsky, L. A.; Saunders, R. S.; Martin, Michael

1993-01-01

324

CoPc and CoPcF16 on gold: Site-specific charge-transfer processes  

PubMed Central

Summary Interface properties of cobalt(II) phthalocyanine (CoPc) and cobalt(II) hexadecafluoro-phthalocyanine (CoPcF16) to gold are investigated by photo-excited electron spectroscopies (X-ray photoemission spectroscopy (XPS), ultraviolet photoemission spectroscopy (UPS) and X-ray excited Auger electron spectroscopy (XAES)). It is shown that a bidirectional charge transfer determines the interface energetics for CoPc and CoPcF16 on Au. Combined XPS and XAES measurements allow for the separation of chemical shifts based on different local charges at the considered atom caused by polarization effects. This facilitates a detailed discussion of energetic shifts of core level spectra. The data allow the discussion of site-specific charge-transfer processes. PMID:24991487

Petraki, Fotini; Uihlein, Johannes; Aygl, Umut; Chass, Thomas

2014-01-01

325

Real-time renormalization group in frequency space: A two-loop analysis of the nonequilibrium anisotropic Kondo model at finite magnetic field  

NASA Astrophysics Data System (ADS)

We apply a recently developed nonequilibrium real-time renormalization group (RG) method in frequency space to describe nonlinear quantum transport through a small fermionic quantum system coupled weakly to several reservoirs via spin and/or orbital fluctuations. Within a weak-coupling two-loop analysis, we derive analytic formulas for the nonlinear conductance and the kernel determining the time evolution of the reduced density matrix. A consistent formalism is presented how the RG flow is cut off by relaxation and dephasing rates. We apply the general formalism to the nonequilibrium anisotropic Kondo model at finite magnetic field. We consider the weak-coupling regime, where the maximum of voltage and bare magnetic field is larger than the Kondo temperature. In this regime, we calculate the nonlinear conductance, the magnetic susceptibility, the renormalized spin relaxation and dephasing rates, and the renormalized g factor. All quantities are considered up to the first logarithmic correction beyond leading order at resonance. Up to a redefinition of the Kondo temperature, we confirm previous results for the conductance and the magnetic susceptibility in the isotropic case. In addition, we present a consistent calculation of the resonant line shapes, including the determination whether the spin relaxation or dephasing rate cuts off the logarithmic divergence. Furthermore, we calculate quantities characterizing the exponential decay of the time evolution of the magnetization. In contrast to the conductance, we find that the derivative of the spin relaxation (dephasing) rate with respect to the magnetic field is logarithmically enhanced (suppressed) for voltages smaller (larger) than the renormalized magnetic field, and that the logarithmic divergence is cut off by the opposite rate. The renormalized g factor is predicted to show a symmetric logarithmic suppression at resonance, which is cut off by the spin relaxation rate. We propose a three-terminal setup to measure the suppression at resonance. For all quantities, we analyze also the anisotropic case and find additional nonequilibrium effects at resonance.

Schoeller, Herbert; Reininghaus, Frank

2009-07-01

326

SPITZER MIPS OBSERVATIONS OF STARS IN THE PICTORIS MOVING GROUP L. M. Rebull,1  

E-print Network

SPITZER MIPS OBSERVATIONS OF STARS IN THE #12; PICTORIS MOVING GROUP L. M. Rebull,1 K. R, in the nearby ($30 pc), young ($12 Myr) #12; Pictoris moving group (BPMG). In sev- eral cases, the new MIPS: individual (#12; Pictoris moving group) 1. INTRODUCTION In recent years, several nearby (P100 pc) young (P200

Mannings, Vince

327

36 CFR 1280.85 - What space in the National Archives at College Park is available for use by non-NARA groups and...  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false What space in the National Archives at College...NARA FACILITIES USE OF NARA FACILITIES What Rules Apply to Use NARA Public Areas in...Archives at College Park, Md 1280.85 What space in the National Archives at...

2012-07-01

328

36 CFR 1280.85 - What space in the National Archives at College Park is available for use by non-NARA groups and...  

...2014-07-01 2014-07-01 false What space in the National Archives at College...NARA FACILITIES USE OF NARA FACILITIES What Rules Apply to Use NARA Public Areas in...Archives at College Park, Md 1280.85 What space in the National Archives at...

2014-07-01

329

An unusal case of facile non-degenerate P-C bond making and breaking.  

PubMed

Oxidation of Li/X phosphinidenoid complex 2, obtained via selective deprotonation from the P-H precursor 1, with [Ph(3)C]BF(4) led to the formation of two P-F substituted diorganophosphane complexes 6,7; the latter tautomer 7 formed via H-shift from 6. In contrast, oxidation of 2 with [(p-Tol)(3)C]BF(4) led to three major and one minor intermediates at low temperature, which we tentatively assign to two pairs of P-C atropisomers 10?a,a' and 10?c,c' and which differ by the relative orientations of their CH(SiMe(3))(2) and W(CO)(5) groups. Conversion of all isomers led finally to complex 11 having a ligand with a long P-C bond to the central trityl* carbon atom, firmly established by single-crystal X-ray analysis. DFT calculations at the B3LYP/def2-TZVPP//BP86/def2-TZVP level of theory on real molecular entities revealed the structures of the in situ formed combined singlet diradicals (4+5 and 5+9) and the nature of intermediates on the way to the final product, complex 11. Remarkable is that all isomers of 11 possess relative energies in the narrow energy regime of about 20?kcal ?mol(-1). A preliminary study revealed that complex 11 undergoes selective P-C bond cleavage at 75?C in toluene solution. PMID:22488865

Nesterov, Vitaly; zbolat-Schn, Aysel; Schnakenburg, Gregor; Shi, Lili; Cangnl, Asli; van Gastel, Maurice; Neese, Frank; Streubel, Rainer

2012-06-01

330

Empirically modelled Pc3 activity based on solar wind parameters  

NASA Astrophysics Data System (ADS)

It is known that under certain solar wind (SW)/interplanetary magnetic field (IMF) conditions (e.g. high SW speed, low cone angle) the occurrence of ground-level Pc3-4 pulsations is more likely. In this paper we demonstrate that in the event of anomalously low SW particle density, Pc3 activity is extremely low regardless of otherwise favourable SW speed and cone angle. We re-investigate the SW control of Pc3 pulsation activity through a statistical analysis and two empirical models with emphasis on the influence of SW density on Pc3 activity. We utilise SW and IMF measurements from the OMNI project and ground-based magnetometer measurements from the MM100 array to relate SW and IMF measurements to the occurrence of Pc3 activity. Multiple linear regression and artificial neural network models are used in iterative processes in order to identify sets of SW-based input parameters, which optimally reproduce a set of Pc3 activity data. The inclusion of SW density in the parameter set significantly improves the models. Not only the density itself, but other density related parameters, such as the dynamic pressure of the SW, or the standoff distance of the magnetopause work equally well in the model. The disappearance of Pc3s during low-density events can have at least four reasons according to the existing upstream wave theory: 1. Pausing the ion-cyclotron resonance that generates the upstream ultra low frequency waves in the absence of protons, 2. Weakening of the bow shock that implies less efficient reflection, 3. The SW becomes sub-Alfvnic and hence it is not able to sweep back the waves propagating upstream with the Alfvn-speed, and 4. The increase of the standoff distance of the magnetopause (and of the bow shock). Although the models cannot account for the lack of Pc3s during intervals when the SW density is extremely low, the resulting sets of optimal model inputs support the generation of mid latitude Pc3 activity predominantly through upstream waves.

Heilig, B.; Lotz, S.; Ver?, J.; Sutcliffe, P.; Reda, J.; Pajunp, K.; Raita, T.

2010-09-01

331

Pc5 micropulsation power at conjugate high-latitude locations  

NASA Astrophysics Data System (ADS)

The micropulsation power, integrated over the Pc5 frequency range, has been calculated for the horizontal component of the geomagnetic field at two high-latitude conjugate locations: Dumont D'Urville (corrected geomagnetic coordinates: 80.61S, 235.76E) and Mould Bay (corrected geomagnetic coordinates: 80.85N, 272.65E). Because of the different distances between the geographic and the geomagnetic poles in each hemisphere, the comparison between the Pc5 power observed at Dumont D'Urville and at Mould Bay shows the relative importance of geomagnetic and solar illumination effects in driving low-frequency micropulsation activity. In particular, similarities observed at the two sites can be explained in terms of their common geomagnetic characteristics, while differences can be attributed to the different sunlight or solar zenith angle configurations. Results show that the local summer Pc5 power is statistically higher in the northern hemisphere than in the southern one. This hemispherical difference is smaller for the local equinoxes, and it is only very slight or absent for local winters. These findings are interpreted in terms of the proportionality between the Pc5 power and the ionospheric conductance, which is higher at Mould Bay owing to more permanent and direct sunlight conditions during local summers and equinoxes. Thus the different geographic coordinates affect the Pc5 power at the two considered sites so much so that their effect is visible regardless of the geomagnetic similarities. However, the influence of the geomagnetic activity on Pc5 power is found to be more significant than these geographical effects or than the seasonal effects. In fact, for Kp < 2 the difference in simultaneous observations at Mould Bay and at Dumont D'Urville is 70%. The magnetic local time modulation of Pc5 power is similar in both hemispheres, since it is determined by the equivalent geomagnetic characteristics and regardless of possible geographical differences. In particular, the occurrence of higher Pc5 power observed at Mould Bay than at Dumont D'Urville is not localized in one specific magnetic local time sector. The present observations are compared with previous results regarding solar illumination effects on geomagnetic activity and on auroral brightness. Finally, no solar cycle effect is observed on either the Pc5 power level, on its hemispherical dependence, or on its daily modulation.

Ballatore, Paola

2003-04-01

332

Astroglia overexpressing heme oxygenase-1 predispose co-cultured PC12 cells to oxidative injury.  

PubMed

The mechanisms responsible for the progressive degeneration of dopaminergic neurons and pathologic iron deposition in the substantia nigra pars compacta of patients with Parkinson's disease (PD) remain unclear. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in the oxidative degradation of heme to ferrous iron, carbon monoxide, and biliverdin, is upregulated in affected PD astroglia and may contribute to abnormal mitochondrial iron sequestration in these cells. To determine whether glial HO-1 hyper-expression is toxic to neuronal compartments, we co-cultured dopaminergic PC12 cells atop monolayers of human (h) HO-1 transfected, sham-transfected, or non-transfected primary rat astroglia. We observed that PC12 cells grown atop hHO-1 transfected astrocytes, but not the astroglia themselves, were significantly more susceptible to dopamine (1 microM) + H(2)O(2) (1 microM)-induced death (assessed by nuclear ethidium monoazide bromide staining and anti-tyrosine hydroxylase immunofluorescence microscopy) relative to control preparations. In the experimental group, PC12 cell death was attenuated significantly by the administration of the HO inhibitor, SnMP (1.5 microM), the antioxidant, ascorbate (200 microM), or the iron chelators, deferoxamine (400 microM), and phenanthroline (100 microM). Exposure to conditioned media derived from HO-1 transfected astrocytes also augmented PC12 cell killing in response to dopamine (1 microM) + H(2)O(2) (1 microM) relative to control media. In PD brain, overexpression of HO-1 in nigral astroglia and accompanying iron liberation may facilitate the bioactivation of dopamine to neurotoxic free radical intermediates and predispose nearby neuronal constituents to oxidative damage. PMID:17526019

Song, Linyang; Song, Wei; Schipper, Hyman M

2007-08-01

333

In vitro effects of fetal rat cerebrospinal fluid on viability and neuronal differentiation of PC12 cells  

PubMed Central

Background Fetal cerebrospinal fluid (CSF) contains many neurotrophic and growth factors and has been shown to be capable of supporting viability, proliferation and differentiation of primary cortical progenitor cells. Rat pheochromocytoma PC12 cells have been widely used as an in vitro model of neuronal differentiation since they differentiate into sympathetic neuron-like cells in response to growth factors. This study aimed to establish whether PC12 cells were responsive to fetal CSF and therefore whether they might be used to investigate CSF physiology in a stable cell line lacking the time-specific response patterns of primary cells previously described. Methods In vitro assays of viability, proliferation and differentiation were carried out after incubation of PC12 cells in media with and without addition of fetal rat CSF. An MTT tetrazolium assay was used to assess cell viability and/or cell proliferation. Expression of neural differentiation markers (MAP-2 and ?-III tubulin) was determined by immunocytochemistry. Formation and growth of neurites was measured by image analysis. Results PC12 cells differentiate into neuronal cell types when exposed to bFGF. Viability and cell proliferation of PC12 cells cultured in CSF-supplemented medium from E18 rat fetuses were significantly elevated relative to the control group. Neuronal-like outgrowths from cells appeared following the application of bFGF or CSF from E17 and E19 fetuses but not E18 or E20 CSF. Beta-III tubulin was expressed in PC12 cells cultured in any media except that supplemented with E18 CSF. MAP-2 expression was found in control cultures and in those with E17 and E19 CSF. MAP2 was located in neurites except in E17 CSF when the whole cell was positive. Conclusions Fetal rat CSF supports viability and stimulates proliferation and neurogenic differentiation of PC12 cells in an age-dependent way, suggesting that CSF composition changes with age. This feature may be important in vivo for the promotion of normal brain development. There were significant differences in the effects on PC12 cells compared to primary cortical cells. This suggests there is an interaction in vivo between developmental stage of cells and the composition of CSF. The data presented here support an important, perhaps driving role for CSF composition, specifically neurotrophic factors, in neuronal survival, proliferation and differentiation. The effects of CSF on PC12 cells can thus be used to further investigate the role of CSF in driving development without the confounding issues of using primary cells. PMID:22494846

2012-01-01

334

Clustering algorithms for a PC based hardware implementation of the unsupervised classifier for the Shuttle ice detection system  

Microsoft Academic Search

The author introduces a near-real-time method of image processing in a PC-based environment. A segmentation technique based on unsupervised classification is implemented. A prototype for the detection of ice formation on the external tank (ET) of the Space Shuttle is being developed. The objective is to be able to do an online classification of the ET images into distinct regions

Sandeep Jaggi

1991-01-01

335

Software issues for PC-based stereoscopic displays: how to make PC users see stereo  

NASA Astrophysics Data System (ADS)

The PC, as the dominant computer platform, is the most exciting market for stereoscopic displays and applications. Several low-cost stereoscopic display systems have been introduced for PCs, including liquid-crystal shutter (LCS) glasses, low-resolution head-mounted displays, and polarized displays with passive polarized glasses. However, each stereoscopic system has its own proprietary driver, and few drivers support Windows. LCDBios, a DOS driver developed by Donald Sawdai, solved the difficult timing problem of accurately synchronizing LCS glasses to the monitor's refresh without degrading computer system performance. More important, LCDBios also provided the stereoscopic industry with a defacto standard API for displaying stereoscopic images with any LCS glasses. However, the LCDBios API only supported LCS glasses for DOS applications without hardware graphics acceleration. The Stereoscopic Device Interface (SSDI), developed by the authors, now provides a standard architecture and API for driving any stereoscopic display system under DOS and Windows while taking advantage of hardware graphics acceleration. The SSDI architecture consists of the SSDI core, SSDI rendering platform drivers, and SSDI device drivers specific to the stereoscopic hardware. The SSDI architecture is broad enough to support device driver modules for all current stereoscopic hardware, including extensions for head-tracking. SSDI currently runs under Windows 95/98 and DOS, while Windows NT support is under development.

Sawdai, Donald; Hamlin, Gregory J.; Swift, David

1998-04-01

336

Demonstration of a PC 25 Fuel Cell in Russia  

SciTech Connect

This project involved the installation of a 200kW PC25C{trademark} phosphoric-acid fuel cell power plant at Orgenergogaz, a Gazprom industrial site in Russia. In April 1997, a PC25C{trademark} was sold by ONSI Corporation to Orgenergogaz, a subsidiary of the Russian company ''Gazprom''. Due to instabilities in the Russian financial markets, at that time, the unit was never installed and started by Orgenergogaz. In October of 2001 International Fuel Cells (IFC), now known as UTC Fuel Cells (UTCFC), received a financial assistance award from the United States Department of Energy (DOE) entitled ''Demonstration of PC 25 Fuel Cell in Russia''. Three major tasks were part of this award: the inspection of the proposed site and system, start-up assistance, and installation and operation of the powerplant.

John C. Trocciola; Thomas N. Pompa; Linda S. Boyd

2004-09-01

337

Transfer Of Baffle Data Between Macintosh PC And APART  

NASA Astrophysics Data System (ADS)

Opto-mechanical systems which are entered into APART for straylight analysis frequently start out as models on a mechanical drafting program such as ANVIL. A translator, described elsewhere, has been coded in FORTRAN which will create the commands for a program one input file in APART based on an existing mechanical model in ANVIL. Having established this link, it is desirable to transfer the resulting opto-mechanical model to a personal computer (PC) for the purpose of report generation. Even more interesting is the ability to modify this model on the PC or to originate a completely new model on the PC for uplink to ANVIL. Using the program CADMOVER, we have effected two way transfers between a VAX computer and an Apple MacIntosh computer. Examples of this activity are provided.

Wise, Timothy D.; Ely, Philip A.

1989-04-01

338

Regulation of the differentiation of PC12 pheochromocytoma cells.  

PubMed Central

The PC12 clone, developed from a pheochromocytoma tumor of the rat adrenal medulla, has become a premiere model for the study of neuronal differentiation. When treated in culture with nanomolar concentrations of nerve growth factor, PC12 cells stop dividing, elaborate processes, become electrically excitable, and will make synapses with appropriate muscle cells in culture. The changes induced by nerve growth factor lead to cells that, by any number of criteria, resemble mature sympathetic neurons. These changes are accompanied by a series of biochemical alterations occurring in the membrane, the cytoplasm, and the nucleus of the cell. Some of these events are independent of changes in transcription, while others clearly involve changes in gene expression. A number of the alterations seen in the cells involve increases or decreases in the phosphorylation of key cellular proteins. The information available thus far allows the construction of a hypothesis regarding the biochemical basis of PC12 differentiation. PMID:2647474

Fujita, K; Lazarovici, P; Guroff, G

1989-01-01

339

PC-1D installation manual and user's guide  

SciTech Connect

PC-1D is a software package for personal computers that uses finite-element analysis to solve the fully-coupled two-carrier semiconductor transport equations in one dimension. This program is particularly useful for analyzing the performance of optoelectronic devices such as solar cells, but can be applied to any bipolar device whose carrier flows are primarily one-dimensional. This User's Guide provides the information necessary to install PC-1D, define a problem for solution, solve the problem, and examine the results. Example problems are presented which illustrate these steps. The physical models and numerical methods utilized are presented in detail. This document supports version 3.1 of PC-1D, which incorporates faster numerical algorithms with better convergence properties than previous versions of the program. 51 refs., 17 figs., 5 tabs.

Basore, P.A.

1991-05-01

340

Managing PC Operating Systems with a Revision Control System  

E-print Network

During the lifetime of a workstation the system administrator is faced with constant change in system configuration (updates, new software). The users of a workstation, too, may change the system configuration. We describe the necessary concepts for maintaining many similar configured PC clients in a lab environment. The main software component consists of fsrcs,a revision control system similar to RCS and SCCS. The revision control software is available without charge. Motivation This paper was motivated by the need to reduce the huge administrative effort for running a computer training room at the Department of Applied Computer Science. It is the first attempt at our university of a fully automatic client installation and update solution using free software. The students can handle the following from the boot-prompt of the PC client without assistance of the system administrator: 1. Repair or install Linux software (operating system and applications) on the PC. 2. Repair o...

Gottfried Rudorfer; Business Administration

1997-01-01

341

Aspartame-induced apoptosis in PC12 cells.  

PubMed

Aspartame is an artificial sweetner added to many low-calorie foods. The safety of aspartame remains controversial even though there are many studies on its risks. In this study, to understand the physiological effects of trace amounts of artificial sweetners on cells, the effects of aspartame on apoptosis were investigated using a PC12 cell system. In addition, the mechanism of apoptosis induced by aspartame in PC12 cells and effects on apoptotic factors such as cytochrome c, apoptosis-inducing factor, and caspase family proteins were studied by Western blotting and RT-PCR. Aspartame-induced apoptosis in PC12 cells in a dose-dependent manner. In addition, aspartame exposure increased the expressions of caspases 8 and 9, and cytochrome c. These results indicate that aspartame induces apoptosis mainly via mitochondrial pathway involved in apoptosis due to oxigen toxicity. PMID:24355796

Horio, Yukari; Sun, Yongkun; Liu, Chuang; Saito, Takeshi; Kurasaki, Masaaki

2014-01-01

342

Using SMS in Mobile Phone for Home Appliances Controlling Through PC Parallel Port Interfacing  

Microsoft Academic Search

This paper presents a system of the PC remote Controlling with the Mobile Telephone through accessing the main PC ports; serial and parallel. Serial port for transferring data from Mobile phone to PC and parallel port for interfacing PC with real time controlling hardware. The system is implemented by using the SMS (Short Message Service) as associated with all modern

Fadhil T. Aula

343

36 CFR 1280.85 - What space in the National Archives at College Park is available for use by non-NARA groups and...  

Code of Federal Regulations, 2010 CFR

... false What space in the National Archives at College Park is available for use...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives at College Park, Md 1280.85...

2010-07-01

344

36 CFR 1280.74 - What spaces in the National Archives Building are available for use by non-NARA groups and...  

Code of Federal Regulations, 2010 CFR

... false What spaces in the National Archives Building are available for use by non-NARA...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives Building, Washington, Dc ...

2010-07-01

345

36 CFR 1280.74 - What spaces in the National Archives Building are available for use by non-NARA groups and...  

... false What spaces in the National Archives Building are available for use by non-NARA...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives Building, Washington, Dc ...

2014-07-01

346

36 CFR 1280.74 - What spaces in the National Archives Building are available for use by non-NARA groups and...  

Code of Federal Regulations, 2012 CFR

... false What spaces in the National Archives Building are available for use by non-NARA...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives Building, Washington, Dc ...

2012-07-01

347

36 CFR 1280.74 - What spaces in the National Archives Building are available for use by non-NARA groups and...  

Code of Federal Regulations, 2013 CFR

... true What spaces in the National Archives Building are available for use by non-NARA...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives Building, Washington, Dc ...

2013-07-01

348

36 CFR 1280.74 - What spaces in the National Archives Building are available for use by non-NARA groups and...  

Code of Federal Regulations, 2011 CFR

... false What spaces in the National Archives Building are available for use by non-NARA...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives Building, Washington, Dc ...

2011-07-01

349

36 CFR 1280.85 - What space in the National Archives at College Park is available for use by non-NARA groups and...  

Code of Federal Regulations, 2011 CFR

... false What space in the National Archives at College Park is available for use...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives at College Park, Md 1280.85...

2011-07-01

350

METHANE DE-NOX FOR UTILITY PC BOILERS  

SciTech Connect

The project seeks to develop and validate a new pulverized coal combustion system to reduce utility PC boiler NO{sub x} emissions to 0.15 lb/million Btu or less without post-combustion flue gas cleaning. Work during the quarter included completion of the equipment fabrication and installation efforts for the 3-million Btu/h pilot system at BBP's Pilot-Scale Combustion Facility (PSCF) in Worcester, MA. Selection and procurement of the first two test coals and preliminary selection of the final two test coals were completed. Shakedown and commissioning activities were finished and PC Preheat pilot scale tests commenced with PRB coal.

Joseph Rabovitser; Bruce Bryan; Serguei Nester; Stan Wohadlo

2002-01-31

351

Microwave coupling phenomenology of pc (printed-circuit) boards  

SciTech Connect

The final link in the High-Power Microwave (HPM) coupling chain is the distribution of energy on printed-circuit (pc) boards. This distribution is a critical part of the total problem, because the bottom line for damage or upset is what occurs at the component level. Like ports-of-entry (POE's), board coupling paths have their own transfer functions. Since most pc boards are not designed to operate at microwave frequencies, these transfer functions can be very complicated. In addition, active elements on the board are likely to make this part of the problem non-linear. 3 refs., 5 figs.

Bacon, L.D.; Riley, D.J.; Toth, R.P.

1989-01-01

352

METHANE de-NOX for Utility PC Boilers  

SciTech Connect

Large-scale combustion tests with caking bituminous coal has stopped. This stoppage has come about due to limitations in current funding available to continue large scale research and development activities at Riley's Commercial Burner Test Facility (CBTF) of the PC Preheat technology. The CBTF was secured and decommissioned in the previous quarter; work this quarter has focused on disposition of PC Preheat experimental equipment at the CBTF as well as methods for disposal of about 100 tons of residual PRB test coal in storage. GTI was granted a no-cost time extension through September 2005; a final report is due in December 2005.

Bruce Bryan; Joseph Rabovitser; Serguei Nester; Stan Wohadlo

2005-06-30

353

PC-Based Applications Programming on the SRS Control System.  

NASA Astrophysics Data System (ADS)

The CERN PC-based ISOLDE control system has been installed at the SRS electron storage ring at Daresbury Laboratory. The use of Windows NT for the control consoles together with PC and VME front-end computers running under several operating systems has resulted in a flexible and reliable system for accelerator control. The implementation and philosophy of control application programs, based around a suite of Microsoft Visual Basic and Excel programs, is described. In particular, the use of Excel to provide adaptable programs online allows rapid generation of new control functions; orbit correction and servoing at the application level are described as examples of this.

Martlew, Brian; Owen, Hywel; Pugh, Martin; Rawlinson, Bill; Smith, Susan

1997-05-01

354

Real-time Power System Simulator using PC Cluster  

NASA Astrophysics Data System (ADS)

This paper presents details on the development of a fully digital real-time power system simulator Hypersim" on a new hardware architecture called PC cluster. PC cluster is a parallel-processing system composed by commodity hardware. Therefore hardware cost of the developed simulator can be reduced compared with simulators implemented on supercomputers. The authors prototyped a real-time simulator Hypersim" on a 4 CPU cluster. For a small and large size of benchmark power system network, 4 CPU cluster can simulate the network in real-time with 21 and 78 microseconds time step, respectively. This simulator makes us enable to test several equipments in real-time.

Yamamoto, Takaya; Enomoto, Hiroshi; Kuroda, Kenichi; Kono, Yoshiyuki; Taoka, Hisao

355

WIMDA: a muon data analysis program for the Windows PC  

NASA Astrophysics Data System (ADS)

A package for analysing ?SR data has been developed for the PC running Microsoft Windows operating systems (Windows 95, 98 and NT4). Some of the key points considered in the design of the program were that it should run on a typical Windows PC, that it should directly read the binary files produced by muon data acquisition systems, that it should be equally easy to analyse data on-line and off-line and that appropriate features should be included for both pulsed and continuous muon sources.

Pratt, F. L.

2000-08-01

356

Run-08 pC polarization analysis - October 16, 2008  

SciTech Connect

In this note we will discuss the analysis of RHIC run 08 pC data that were collected during February 14 - March 10, 2008. An analysis method that is similar to Run 05 and Run 06 was adopted for Run 08 analysis (except few minor changes, which are described below). A detailed analysis note and a NIM article that describe the pC analysis procedure (for run 05 and run 06) can be found elsewhere. In brief, the analysis consists of calibrating the detectors, determining energy corrections ('dead layers'), determining good runs and extracting the polarization from data.

Dharmawardane,V.; Bazilevsky,A.; Bunce, G.; Gill, R.; Huang, H.; Makdisi, Y.; Nakagawa, I.; Morozov, B.; Okada, H.; Sivertz, M.; Zelenski, A.; Alekseev, I.; Svirida, D.

2009-03-01

357

IUCN Otter Spec. Group Bull. 21(1) 2004 IUCN OTTER SPECIALIST GROUP BULLETIN  

E-print Network

IUCN Otter Spec. Group Bull. 21(1) 2004 IUCN OTTER SPECIALIST GROUP BULLETIN VOLUME 21 ISSUE 1 PAGES 24 - 30 Citation: Alarcon, G.G. and Simões-Lopes, P.C. (2004) The Neotropical Otter Lontra Longicaudis Feeding Habits In A Marine Coastal Area, Southern Brazil . IUCN Otter Spec. Group Bull. 21(1): 24

Simões-Lopes, Paulo César

358

Processing and intracellular localization of rice stripe virus Pc2 protein in insect cells  

SciTech Connect

Rice stripe virus (RSV) belongs to the genus Tenuivirus and its genome consists of four single-stranded RNAs encoding seven proteins. Here, we have analyzed the processing and membrane association of Pc2 encoded by vcRNA2 in insect cells. The enhanced green fluorescent protein (eGFP) was fused to the Pc2 and used for the detection of Pc2 fusion proteins. The results showed that Pc2 was cleaved to produce two proteins named Pc2-N and Pc2-C. When expressed alone, either Pc2-N or Pc2-C could transport to the Endoplasmic reticulum (ER) membranes independently. Further mutagenesis studies revealed that Pc2 contained three ER-targeting domains. The results led us to propose a model for the topology of the Pc2 in which an internal signal peptide immediately followed a cleavage site, and two transmembrane regions are contained.

Zhao, Shuling; Zhang, Gaozhan; Dai, Xuejuan; Hou, Yanling; Li, Min [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China)] [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China); Liang, Jiansheng, E-mail: jsliang@yzu.edu.cn [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China)] [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China); Liang, Changyong, E-mail: cyliang@yzu.edu.cn [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China)] [College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009 (China)

2012-08-01

359

Space languages  

NASA Technical Reports Server (NTRS)

Applications of linguistic principles to potential problems of human and machine communication in space settings are discussed. Variations in language among speakers of different backgrounds and change in language forms resulting from new experiences or reduced contact with other groups need to be considered in the design of intelligent machine systems.

Hays, Dan

1987-01-01

360

Increased expression of the EZH2 polycomb group gene in BMI1-positive neoplastic cells during bronchial carcinogenesis  

Microsoft Academic Search

Polycomb group (PcG) genes are responsible for maintenance of cellular identity and contribute to regulation of the cell cycle. Recent studies have identified several PcG genes as oncogenes, and a role for PcG proteins in human oncogenesis is suspected. We investigated the expression of BMI-1 and EZH2 PcG oncogenes in human bronchial squamous cell carcinomas (SCCs) and bronchial premalignant precursor

Roderick H. J. Breuer; Peter J. F. Snijders; Egbert F. Smit; Thomas G. Sutedja; Richard G. A. B. Sewalt; Arie P. Otte; Kemenade van F. J; Pieter E. Postmus; Chris J. L. M. Meijer; Frank M. Raaphorst

2004-01-01

361

OAST Space Theme Workshop. Volume 3: Working group summary. 1: Navigation, guidance, control (E-1) A. Statement. B. Technology needs (form 1). C. Priority assessment (form 2)  

NASA Technical Reports Server (NTRS)

The six themes identified by the Workshop have many common navigation guidance and control needs. All the earth orbit themes have a strong requirement for attitude, figure and stabilization control of large space structures, a requirement not currently being supported. All but the space transportation theme have need for precision pointing of spacecraft and instruments. In addition all the themes have requirements for increasing autonomous operations for such activities as spacecraft and experiment operations, onboard mission modification, rendezvous and docking, spacecraft assembly and maintenance, navigation and guidance, and self-checkout, test and repair. Major new efforts are required to conceptualize new approaches to large space antennas and arrays that are lightweight, readily deployable, and capable of precise attitude and figure control. Conventional approaches offer little hope of meeting these requirements. Functions that can benefit from increasing automation or autonomous operations are listed.

1976-01-01

362

Falling PC Solitaire Cards: An Open-Inquiry Approach  

ERIC Educational Resources Information Center

Many of us have played the PC Solitaire game that comes as standard software in many computers. Although I am not a great player, occasionally I win a game or two. The game celebrates my accomplishment by pushing the cards forward, one at a time, falling gracefully in what appears to look like a parabolic path in a drag-free environment. One day,

Gonzalez-Espada, Wilson J.

2012-01-01

363

PC-Scheme/Geneva 4.02 log Larry Bartholdi  

E-print Network

turn to Texas In- struments' documentation. You may order TI's manual at the MIT press. It's called: PC Scheme: Users Guide and Language Reference Manual, Trade Edition, Texas Instruments, 416 pp, 1990, ISBN 0 (including all graphic modes, Ega 43 lines, Vga 50 lines, Svga 132 columns. . . ) are supported. The TEXT

Wilkerson, Clarence

364

What's Under Your PC's 'Hood': A Primer for Today's Machines.  

ERIC Educational Resources Information Center

Explains how to decide what type of computer to buy for a small academic library, based on software requirements, staff and patron use, and PC technology. Topics include the central processing unit; types of memory; storage devices; ports; multimedia capabilities; modems; operating systems; and monitors. (LRW)

Chen, Li; Mills, Joyce White

2002-01-01

365

PC software for SAW propagation in anisotropic multilayers  

Microsoft Academic Search

A software package that provides an interactive and graphical environment for surface acoustic wave (SAW) and plate-mode propagation studies in arbitrarily oriented anisotropic and piezoelectric multilayers is described. The software, which runs on an IBM PC with math coprocessor, is based on a transfer-matrix formulation for calculating the characteristics of SAW propagation in multilayers that was originally written for a

E. L. Adler; J. K. Slaboszewicz; G. W. Farnell; C. K. Jen

1990-01-01

366

PC-CUBE: A personal computer based hypercube  

NASA Technical Reports Server (NTRS)

PC-CUBE is an ensemble of IBM PCs or close compatibles connected in the hypercube topology with ordinary computer cables. Communication occurs at the rate of 115.2 K-band via the RS-232 serial links. Available for PC-CUBE is the Crystalline Operating System III (CrOS III), Mercury Operating System, CUBIX and PLOTIX which are parallel I/O and graphics libraries. A CrOS performance monitor was developed to facilitate the measurement of communication and computation time of a program and their effects on performance. Also available are CXLISP, a parallel version of the XLISP interpreter; GRAFIX, some graphics routines for the EGA and CGA; and a general execution profiler for determining execution time spent by program subroutines. PC-CUBE provides a programming environment similar to all hypercube systems running CrOS III, Mercury and CUBIX. In addition, every node (personal computer) has its own graphics display monitor and storage devices. These allow data to be displayed or stored at every processor, which has much instructional value and enables easier debugging of applications. Some application programs which are taken from the book Solving Problems on Concurrent Processors (Fox 88) were implemented with graphics enhancement on PC-CUBE. The applications range from solving the Mandelbrot set, Laplace equation, wave equation, long range force interaction, to WaTor, an ecological simulation.

Ho, Alex; Fox, Geoffrey; Walker, David; Snyder, Scott; Chang, Douglas; Chen, Stanley; Breaden, Matt; Cole, Terry

1988-01-01

367

The interfacing technology of PC-based factory automation systems  

Microsoft Academic Search

The purpose of this paper is to use a 4 axis servo card to design a very friendly man-machine interface to set up a practical PC based industrial controller system. We also introduced a novel pulse generator ICPG9210 which is powerful in multi axis motion control of servo motors

Hung-Yuan Chung; Dar-Win Jang

1995-01-01

368

Augmenting Network Interfaces to Reduce PC Energy Usage  

Microsoft Academic Search

Reducing the energy consumption of PCs is becom- ing increasingly important with rising energy costs and environmental concerns. Sleep states such as S3 (sus- pend to RAM) save energy but prevent the PC from re- sponding to network traffic, for example remote desktop logins, file transfer requests, or content distribution pro - tocols such as bittorrent. We conducted a background

Yuvraj Agarwal; Steve J. Hodges; James Scott; Ranveer Chandra; Paramvir Bahl; Rajesh Gupta

369

Desktop Publishing in a PC-Based Environment.  

ERIC Educational Resources Information Center

Identifies, considers, and interrelates the functionality of hardware, firmware, and software types; discusses the relationship of input and output devices in the PC-based desktop publishing environment; and reports some of what has been experienced in three years of working intensively in/with desktop publishing devices and solutions. (MES)

Sims, Harold A.

1987-01-01

370

SEF.ASSISTANT: Shell for Authoring Language SEF.PC.  

ERIC Educational Resources Information Center

This paper describes SEF.ASSISTANT, a special software shell for authoring languages to be used in the development of courseware serving computer based education (CBE). The capabilities of SEF.ASSISTANT are identified: (1) it will generate programs written in the IBM SEF.PC authoring language; (2) it is compatible with external standard software

Masturzi, Elio R.

371

A PC-based Workstation for Robotic Discectomy  

NASA Technical Reports Server (NTRS)

Ths paper describes a PC-based controller for robot-assisted minimally invasive surgery. The development is motivated by the need of reducing the exposure of operating room personnel to X-rays during surgical procedures such as percutanrous discectomy.

Casadei, C.; Fiorini, P.; Martelli, S.; Montanari, M.; Morri, A.

1998-01-01

372

1-8 Surface Mount PC Board Mountable Pressure Sensor  

E-print Network

or a large hole to interface with the pressure media. DIMENSIONS #12;PC Board Mountable Pressure Sensor Model Pressure Hysteresis ­0.1 0.1 % Span Input & Output Resistance 3500 5000 6000 Temperature Coefficient - Span ­0.20 %/°C 2 Temperature Coefficient - Zero +0.05 %/°C 2 Temperature Coefficient - Resistance +0

Berns, Hans-Gerd

373

Deciding when It's Time to Buy a New PC  

ERIC Educational Resources Information Center

How to best decide when it's time to replace your PC, whether at home or at work, is always tricky. Spending on computers can make you more productive, but it's money you otherwise cannot spend, invest or save, and faster systems always await you in the future. What is clear is that the computer industry really wants you to buy, and the computer

Goldsborough, Reid

2004-01-01

374

PC vs. Mac--Which Way Should You Go?  

ERIC Educational Resources Information Center

Outlines the factors in hardware, software, and administration to consider in developing specifications for choosing a computer operating system. Compares Microsoft Windows 95/NT that runs on PC/Intel-based systems and System 7.5 that runs on the Apple-based systems. Lists reasons why the Microsoft platform clearly stands above the Apple platform.

Wodarz, Nan

1997-01-01

375

The PC index: method of calculation and physical sense  

NASA Astrophysics Data System (ADS)

The PC index has been introduced [Troshichev and Andrezen, 1985; Troshichev et al., 1988] to characterize magnetic activity in the polar caps generated by the solar wind coupling with the magnetosphere. The concept of the antisunward convection within the polar cap, controlled by the interplanetary electric field EKL determined by Kan and Lee (1979), served as a basis for the method of the index calculation. Value of disturbances in the polar cap geomagnetic H and D (or X and Y) components form the basis for derivation of the PC index. The technique of PC index derivation consists of two separate procedures: (1) derivation of the statistically justified regression coefficients determining relationship between the coupling function EKL and vector of polar cap magnetic disturbance ?F, and (2) calculation of PC indices by data on current ?F values with use of the regression coefficients established in course of the first procedure. To exclude from examination the geomagnetic field changes unrelated to the solar wind variations the value of geomagnetic disturbance is calculated in reference to the quiet daily variation. The regression coefficients ? (slope) and ? (intersection) describing a linear link between values ?F and EKL are calculated in combination with the optimal angle ? providing the highest correlation between ?F and EKL. Parameters ?, ? and ? are derived based on the statistically justified sets of data. As a result the PC index corresponding to the value of coupling function EKL, irrespective of UT time, season and point of observation is determined. Validation of the PC proper derivation has been testified by the following requirements imposed on the calculated PCN and PCS indices: PCN and PCS indices should be consistent with the interplanetary electric field EKL; PCN and PCS indices should be in close agreement with each other irrespective of season and UT time; indices should not demonstrate seasonal variation; indices should not demonstrate regular daily variation (i.e. dependence on UT-time). By its derivation, the PC index is regarded as a proxy of the interplanetary electric field EKL affecting the magnetosphere in course of constant solar wind - magnetosphere coupling.

Janzhura, A.; Troshichev, O.

2012-04-01

376

OAST Space Theme Workshop. Volume 3: Working group summary. 7: Material (M-1). A. Statement. B. Technology needs (form 1). C. Priority assessment (form 2)  

NASA Technical Reports Server (NTRS)

The approach of matching technology areas with various themes needs was not effective for the materials and thermal control discipline because of the diversity of requirements for each. Top priorities were evolved from the advanced space transportation system and the space power platform because these are essential building blocks in fulfilling some of the other themes. Important needs identified include life long-life cryogenic cooling systems for sensors, masers, and other devices and the needs for lightweight nuclear shielding materials for nuclear electric propulsion.

1976-01-01

377

36 CFR 1280.85 - What space in the National Archives at College Park is available for use by non-NARA groups and...  

Code of Federal Regulations, 2013 CFR

...2012-07-01 true What space in the National Archives at College Park is available for use...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES...the Washington, DC, Area? National Archives at College Park, Md 1280.85...

2013-07-01

378

Electrochemical evidence of intramolecular electronic communication in Zr and Hf phthalocyanines bearing ferrocene-containing ?-diketonato axial ligands: structure of [PcHf(FcCOCHCOC6H5)2].  

PubMed

The series of zirconium(IV) and hafnium(IV) phthalocyanine complexes [PcM(FcCOCHCOR)2] (Pc = phthalocyaninato; M = Zr; R = CF3 (1), CH3 (2), C6H5 (3), Fc ((C5H5)Fe(C5H4), 4), as well as M = Hf ; R = CF3 (5), CH3 (6), C6H5 (7), and Fc (8)) were synthesized. A single-crystal X-ray diffraction analysis of the structure of [PcHf(FcCOCHCOC6H5)2], 7 (Z = 2, space group P1), showed the two axial ?-diketonato ligands were orientated in such a way that the ferrocenyl groups were positioned diagonally opposite each other. From the structural determination of 7 it was clear that these complexes have a distorted D4h symmetry at the coordination site of the metal centers, which explains a splitting of the UV-vis Q band into Qx and Qy components with 3 ? ??(max,Q) ? 10 nm. Cyclic and square wave voltammetric studies in CH2Cl2/[N((n)Bu)4][B(C6F5)4] allowed observation of at least three phthalocyaninato macrocycle-based redox couples as well as all (i.e., two or four) well-resolved ferrocenyl couples in 1-8. For M = Zr and R = Fc, formal reduction potentials of the four ferrocenyl groups were found to be E' = 296, 386, 538, and 687 mV versus free ferrocene. Spectroelectrochemical evidence, UV-vis Q-band maximum wavelengths, and HOMO-LUMO energy gaps as expressed by ?E'I-III = ?E'wave I - ?E'wave III were mutually consistent, indicating that the first phthalocyaninato ring-based oxidation occurs before ferrocenyl oxidations take place. The potential for each redox process was found to be dependent on the sum of ?-diketonato R-group group electronegativities, ??R. Mathematical relationships for the dependency of E' on ??R for all four observed ring-based redox processes as well as for the ferrocenyl-based redox processes were determined. This allowed prediction of potentials for redox processes that fall outside the workable potential window of the solvent. No significant differences were found between the corresponding redox potentials of zirconium and hafnium analogues bearing the same axial ligands. PMID:23971994

Buitendach, Blenerhassitt E; G?gor, Anna; Swarts, Jannie C

2013-09-16

379

Chromosomal assignment of the genes for proprotein convertases PC4, PC5, and PACE 4 in mouse and human  

SciTech Connect

The genes for three subtilisin/kexin-like proprotein convertases, PC4, PC5, and PACE4, were mapped in the mouse by RFLP analysis of a DNA panel from a (C57BL/6JEi x SPRET/Ei) F{sub 1} x SPRET/Ei backcross. The chromosomal locations of the human homologs were determined by Southern blot analysis of a DNA panel from human-rodent somatic cell hybrids, most of which contained a single human chromosome each. The gene for PC4 (Pcsk4 locus) mapped to mouse chromosome 10, close to the Adn (adipsin, a serine protease) locus and near the Amh (anti-Mullerian hormone) locus; in a human, the gene was localized to chromosome 19. The gene for PC5 (Pcsk5 locus) mapped to mouse chromosome 19 close to the Lpc1 (lipoacortin-1) locus and, in human, was localized to chromosome 9. The gene for PACE4 (Pcsk6 locus) mapped to mouse chromosome 7, at a distance of 13 cM from the Pcsk3 locus, which specifies furin, another member of this family of enzymes previoulsy mapped to this chromosome. This is in concordance with the known close proximity of these two loci in the homologous region on human chromosome 15q25-qter. Pcsk3 and Pcsk6 mapped to a region of mouse chromosome 7 that has been associated cytogenetically with postnatal lethality in maternal disomy, suggesting that these genes might be candidates for imprinting. 43 refs., 3 figs., 2 tabs.

Mbikay, M.; Seidah, N.G.; Chretien, M. [Univ. of Montreal, Quebec (Canada)] [and others] [Univ. of Montreal, Quebec (Canada); and others

1995-03-01

380

PC 4 - PC 1 magnetic pulsations at synchronous orbit and their relation to pulsations on the ground  

NASA Technical Reports Server (NTRS)

Three types of Pc 4 pulsations with periods in the range 40-200 s have been identified in the ATS 6 satellite data. Two types are not observed on the ground. Both of these are accompanied by Pc 1-2 activity that is seen simultaneously both at the satellite and on the ground. One of these two types occurs during substorms and coincides with the development of the IPDP subtype of Pc 1-2. The other is observed in the magnetosphere during slow, smooth changes of the background magnetic field during the recovery phase of storms. Puslation amplitude for these two types is from 5 to several tens of nanoTeslas. The third type of Pc 4 pulsation has significantly smaller amplitudes in the magnetosphere and can be observed on the ground with amplitudes usually greater than in the magnetosphere. The properties of the first two types of long-period pulsations suggest that the mechanism for their generation is the drift-dissipative instability of the ring current plasma.

Maltseva, N.; Troitskaia, V. A.; Shchepetnov, R.; Pokhotelov, O.; Gokhberg, M.; Pilipenko, V.; Mcpherron, R.; Barfield, J.

1982-01-01

381

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION  

E-print Network

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 1 NASA Earth Science Data Systems Software Reuse #12;NATIONAL AERONAUTICS AND SPACE ADMINISTRATION ESDS Reuse Working Group 2 Award Background: http://www.esdswg.com/softwarereuse/Resources/awards/ #12;NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

Christian, Eric

382

MIB-1 and PC-10 immunostaining for the assessment of proliferative activity in primary acquired melanosis without and with atypia  

PubMed Central

AIMSTo compare the proliferative activity of intraepithelial melanocytes in primary acquired melanosis (PAM) without atypia and PAM with atypia by immunohistochemical staining for the Ki-67 antigen and the proliferating cell nuclear antigen (PCNA).?METHODSFormalin fixed, paraffin embedded sections from 35archival specimens of PAM without atypia (n=19) and with atypia (n=16) were studied by immunostaining with MIB-1 and PC-10 monoclonal antibodies that react with the Ki-67 antigen and PCNA respectively. The results were calculated as the mean number of positive cells per eyepiece grid. All specimens were evaluated by two masked observers, and the interobserver reproducibility was assessed.?RESULTSThe means of the positive cell count in PAM with atypia were significantly higher compared with PAM without atypia for both observers, in both the PC-10 and the MIB-1 stained sections. In a linear least square model that estimated the interobserver and between group variation, the difference of MIB-1 and PC-10 positive cell count between PAM without and with atypia remained highly significant. The difference between the observers was not significant.?CONCLUSIONSImmunostaining with MIB-1 and PC-10 demonstrated that PAM with atypia has higher proliferative activity than PAM without atypia. This method was found to be reproducible between different observers.?? Keywords: primary acquired melanosis; immunostaining; atypia PMID:9924341

Chowers, I.; Livni, N.; Solomon, A.; Zajicek, G.; Frucht-Pery, J.; Folberg, R.; Pe'er, J.

1998-01-01

383

Polycomb Group Proteins Set the Stage for Early Lineage Commitment  

E-print Network

Precise control of gene expression patterns is critical for the specification of cellular diversity during metazoan development. Polycomb group (PcG) proteins comprise a class of transcriptional modifiers that have dynamic ...

Surface, Lauren Elizabeth

384

METHANE de-NOX for Utility PC Boilers  

SciTech Connect

The overall project objective is the development and validation of an innovative combustion system, based on a novel coal preheating concept prior to combustion, that can reduce NO{sub x} emissions to 0.15 lb/million Btu or less on utility pulverized coal (PC) boilers. This NO{sub x} reduction should be achieved without loss of boiler efficiency or operating stability, and at more than 25% lower levelized cost than state-of-the-art SCR technology. A further objective is to ready technology for full-scale commercial deployment to meet the market demand for NO{sub x} reduction technologies. Over half of the electric power generated in the U.S. is produced by coal combustion, and more than 80% of these units utilize PC combustion technology. Conventional measures for NOx reduction in PC combustion processes rely on combustion and post-combustion modifications. A variety of combustion-based NO{sub x} reduction technologies are in use today, including low-NO{sub x} burners (LNBs), flue gas recirculation (FGR), air staging, and natural gas or other fuel reburning. Selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) are post-combustion techniques. NO{sub x} reduction effectiveness from these technologies ranges from 30 to 60% and up to 90-93% for SCR. Typically, older wall-fired PC burner units produce NO{sub x} emissions in the range of 0.8-1.6 lb/million Btu. Low-NO{sub x} burner systems, using combinations of fuel staging within the burner and air staging by introduction of overfire air in the boiler, can reduce NO{sub x} emissions by 50-60%. This approach alone is not sufficient to meet the desired 0.15 lb/million Btu NO{sub x} standard with a range of coals and boiler loads. Furthermore, the heavy reliance on overfire air can lead to increased slagging and corrosion in furnaces, particularly with higher-sulfur coals, when LNBs are operated at sub-stoichiometric conditions to reduce fuel-derived NOx in the flame. Therefore, it is desirable to minimize the need for overfire air by maximizing NO{sub x} reduction in the burner. The proposed combustion concept aims to greatly reduce NO{sub x} emissions by incorporating a novel modification to conventional or low-NO{sub x} PC burners using gas-fired coal preheating to destroy NO{sub x} precursors and prevent NO{sub x} formation. A concentrated PC stream enters the burner, where flue gas from natural gas combustion is used to heat the PC up to about 1500 F prior to coal combustion. Secondary fuel consumption for preheating is estimated to be 3 to 5% of the boiler heat input. This thermal pretreatment releases coal volatiles, including fuel-bound nitrogen compounds into oxygen-deficient atmosphere, which converts the coal-derived nitrogen compounds to molecular N{sub 2} rather than NO. Design, installation, shakedown, and testing on Powder River Basin (PRB) coal at a 3-million Btu/h pilot system at RPI's (Riley Power, Inc.) pilot-scale combustion facility (PSCF) in Worcester, MA demonstrated that the PC PREHEAT process has a significant effect on final O{sub x} formation in the coal burner. Modifications to both the pilot system gas-fired combustor and the PC burner led to NO{sub x} reduction with PRB coal to levels below 0.15 lb/million Btu with CO in the range of 35-112 ppmv without any furnace air staging.

Bruce Bryan; Serguei Nester; Joseph Rabovitser; Stan Wohadlo

2005-09-30

385

CARES/PC - CERAMICS ANALYSIS AND RELIABILITY EVALUATION OF STRUCTURES  

NASA Technical Reports Server (NTRS)

The beneficial properties of structural ceramics include their high-temperature strength, light weight, hardness, and corrosion and oxidation resistance. For advanced heat engines, ceramics have demonstrated functional abilities at temperatures well beyond the operational limits of metals. This is offset by the fact that ceramic materials tend to be brittle. When a load is applied, their lack of significant plastic deformation causes the material to crack at microscopic flaws, destroying the component. CARES/PC performs statistical analysis of data obtained from the fracture of simple, uniaxial tensile or flexural specimens and estimates the Weibull and Batdorf material parameters from this data. CARES/PC is a subset of the program CARES (COSMIC program number LEW-15168) which calculates the fast-fracture reliability or failure probability of ceramic components utilizing the Batdorf and Weibull models to describe the effects of multi-axial stress states on material strength. CARES additionally requires that the ceramic structure be modeled by a finite element program such as MSC/NASTRAN or ANSYS. The more limited CARES/PC does not perform fast-fracture reliability estimation of components. CARES/PC estimates ceramic material properties from uniaxial tensile or from three- and four-point bend bar data. In general, the parameters are obtained from the fracture stresses of many specimens (30 or more are recommended) whose geometry and loading configurations are held constant. Parameter estimation can be performed for single or multiple failure modes by using the least-squares analysis or the maximum likelihood method. Kolmogorov-Smirnov and Anderson-Darling goodness-of-fit tests measure the accuracy of the hypothesis that the fracture data comes from a population with a distribution specified by the estimated Weibull parameters. Ninety-percent confidence intervals on the Weibull parameters and the unbiased value of the shape parameter for complete samples are provided when the maximum likelihood technique is used. CARES/PC is written and compiled with the Microsoft FORTRAN v5.0 compiler using the VAX FORTRAN extensions and dynamic array allocation supported by this compiler for the IBM/MS-DOS or OS/2 operating systems. The dynamic array allocation routines allow the user to match the number of fracture sets and test specimens to the memory available. Machine requirements include IBM PC compatibles with optional math coprocessor. Program output is designed to fit 80-column format printers. Executables for both DOS and OS/2 are provided. CARES/PC is distributed on one 5.25 inch 360K MS-DOS format diskette in compressed format. The expansion tool PKUNZIP.EXE is supplied on the diskette. CARES/PC was developed in 1990. IBM PC and OS/2 are trademarks of International Business Machines. MS-DOS and MS OS/2 are trademarks of Microsoft Corporation. VAX is a trademark of Digital Equipment Corporation.

Szatmary, S. A.

1994-01-01

386

OAST Space Theme Workshop. Volume 3: Working group summary. 3: Sensors (E-3). A. Statement. B. Technology needs (form 1). C. Priority assessment (form 2). D. Additional assessment  

NASA Technical Reports Server (NTRS)

Developments required to support the space power, SETI, solar system exploration and global services programs are identified. Instrumentation and calibration sensors (rather than scientific) are needed for the space power system. Highly sophisticated receivers for narrowband detection of microwave sensors and sensors for automated stellar cataloging to provide a mapping data base for SETI are needed. Various phases of solar system exploration require large area solid state imaging arrays from UV to IR; a long focal plane telescope; high energy particle detectors; advanced spectrometers; a gravitometer; and atmospheric distanalyzer; sensors for penetrometers; in-situ sensors for surface chemical analysis, life detection, spectroscopic and microscopic analyses of surface soils, and for meteorological measurements. Active and passive multiapplication sensors, advanced multispectral scanners with improved resolution in the UV and IR ranges, and laser techniques for advanced probing and oceanographic characterization will enhance for global services.

1976-01-01

387

Fully automatic identification of AC and PC landmarks on brain MRI using scene analysis.  

PubMed

We describe a method for identification of brain structures from MRI data sets. The bulk of the paper concerns an automatic system for finding the anterior and posterior commissures [(AC) and (PC)] in the midsagittal plane. These landmarks are key for the definition of the Talairach space, commonly used in stereotactic neurosurgery, in the definition of common coordinate systems for the pooling of functional positron emission tomography (PET) images and for neuroanatomy studies. The process works according to a step-by-step procedure: it first analyzes the skull limits. A grey-level histogram is then calculated and allows an automated selection of thresholds. Then, the interhemispheric plane is detected. Following an advanced scene analysis in the midsagittal plane for anatomical structures, the AC and the PC are identified. Experimentally, with a set of 200 patients, the process never failed. Its performances and limits are comparable to that of neuroanatomy experts. Those results are due to a high degree of robustness at each step of the program. PMID:9368116

Vrard, L; Allain, P; Travre, J M; Baron, J C; Bloyet, D

1997-10-01

388

Conformal Carroll groups  

NASA Astrophysics Data System (ADS)

Conformal extensions of Lvy-Leblond's Carroll group, based on geometric properties analogous to those of Newton-Cartan space-time are proposed. The extensions are labeled by an integer k. This framework includes and extends our recent study of the Bondi-Metzner-Sachs (BMS) and Newman-Unti (NU) groups. The relation to conformal Galilei groups is clarified. Conformal Carroll symmetry is illustrated by Carrollian photons. Motion both in the Newton-Cartan and Carroll spaces may be related to that of strings in the Bargmann space.

Duval, C.; Gibbons, G. W.; Horvathy, P. A.

2014-08-01

389

Group Dynamics in Long -term blind endeavors on Earth as an analog for Remote Space Missions (Lewis & Clark Expedition, 1803 - 1806, Dynamic Analysis)  

NASA Astrophysics Data System (ADS)

In 1803 President Thomas Jefferson set fourth a military expedition led by Captains newline M Lewis and W Clark L C Expedition on an exploration to learn more about the large territory of land the U S had just purchased from France Cavan 1991 Their mission was to find a direct water route to the Pacific Ocean for the purpose of commerce and further industrial development Edwards 1999 Looking back at the events of this exploration there are many similarities to the experiences future human space explorers will face as we look to colonize the Moon and travel to Mars and beyond NASA Vision for Space Exploration 2004 - The L C Expedition lasted almost three years and involved a crew of 43 men traveling up the Missouri River to explore the unknown lands and a possible water route to the Pacific Ocean newline - The expedition took place far away from customary comfortable environments known to European settlers in early 18th century newline - The expedition involved a remotely confined high-perceived risk environment with high levels of uncertainty providing stresses and every day challenges for the crew newline - Supplies brought on the mission were limited mainly a mass weight issue rather than cost therefore the discovery and use of environmental resources In-Situ Resource Utilization approach including info-resources to mitigate uncertainty was necessary for crew survival The environments astronauts will encounter in space and on the Moon and Mars due to high risk and uncertainty will be in many aspects similar

Allner, M.; Rygalov, V.; Reilly, J.

390

METHANE de-NOX for Utility PC Boilers  

SciTech Connect

Large-scale combustion tests with caking bituminous coal has stopped. This stoppage has come about due to limitations in current funding available to continue large scale research and development activities at Riley Power's Commercial Burner Test Facility (CBTF) of the PC Preheat technology. The CBTF was secured and decommissioned in the previous quarter; work this quarter work completed the securing the proper disposition of all PC Preheat experimental equipment at the PSCF and CBTF and completing negotiations with AES Westover (a power plant in Johnson City, New York) to accept 130 tons of residual PRB test coal in storage. The coal transport to Westover occurred at the end of August. GTI was granted a no-cost time extension through September 2005; immediate efforts are focused on completing a draft final report, which is due in October 31, 2005 and the final report in December.

Joseph Rabovitser; Serguei Nester; Stan Wohadlo

2005-09-30

391

Conversion from 8800 to 8800PC -- Evaluation and experience  

SciTech Connect

Though a final version of the software is pending the 8800PC operating system host computer is a welcomed change from the old Digital (DEC) host computer. The 8800PC host computer uses the Windows NT operating system and has proven to be very user friendly. Descriptive window messages replace the cryptic coding of the DEC host. Though numerous electrical components were replaced, system calibration remained constant. Calibrated Thermoluminescent (TL) output from a randomly selected 8815 field card was measured before and after the upgrade. The % difference, when comparing calibrated output from an upgraded reader to the non upgraded reader, ranged from 0.2 to 3%. The most disappointing aspect of the upgrade experience was the lag time between hardware installation and software completion.

Miner, A.E.; Lawson, B.J. [Lockheed Martin, Schenectady, NY (United States)

1998-03-20

392

Calibration tools for PC-based vision assessment.  

PubMed

This paper details the research and development of the PC Vision system, a unique calibration and monitoring subsystem that will enable use of personal computers as accurately calibrated and controlled vision test instruments. The need for such a system is evident. Display intensity and chromaticity, test distance, room illumination, and a number of other variables must be controlled to avoid unexplained discrepancies in test outcomes, within and between individuals and test locations. Modern displays (CRT-, LCD-, or projector-based) have sufficient resolution, gamut, and stability to allow high-quality stimulus presentation. The PC Vision system consists of two categorical functions - one to calibrate screen properties, the other to monitor room and test setup conditions - packaged into a fully integrated hardware prototype. PMID:19964242

Rolkosky, David J; Dagnelie, Gislin; Kramer, Kevin; Havey, Gary; Seifert, Gregory J

2009-01-01

393

Western State Hospital: implementing a MUMPS-based PC network.  

PubMed

Western State Hospital, a state-administered 1,200-bed mental health institution near Tacoma, Wash., confronted the challenge of automating its large campus through the application of the Healthcare Integrated Information System (HIIS). It is the first adaptation of the Veterans Administration's Decentralized Hospital Computer Program software in a mental health institution of this size, and the first DHCP application to be installed on a PC client/server network in a large U.S. hospital. PMID:10112114

Russ, D C

1991-06-01

394

The 3D brain topography based on PC  

Microsoft Academic Search

Brain topographic mapping is a useful technique for visualizing brain activity. It clarifies the spatial and temporal relationships between different cortical areas. However, 3D topographic mapping systems are only available in dedicated image processing and image synthesis workstation environments. In this paper, we aim at a PC-based 3D topographic mapping system, which is simple, low-cost and easy to operate. This

K. H. Kim; J. H. Kwon; D. H. Lee; S. I. Kim

1997-01-01

395

EMC characterization of PC-based data acquisition systems  

Microsoft Academic Search

This paper deals with the electromagnetic susceptibility of PC-based data acquisition systems. The data acquisition system (personal computer + data acquisition board) is approached as a whole system and subjected to all the conducted and radiated interference considered by IEC-61000-4-1. The experimental tests, carried out in shielded and semi-anechoic environments, highlight the relevance of a specific EMI characterization of this

G. Betta; D. Capriglione; C. De Capua; C. Landi

2002-01-01

396

Structure and Water Permeability of Fully Hydrated DiphytanoylPC  

PubMed Central

Diphytanoylphosphatidylcholine (DPhyPC) is a branched chain lipid often used for model membrane studies, including peptide/lipid interactions, ion channels and lipid rafts. This work reports results of volume measurements, water permeability measurements Pf, X-ray scattering from oriented samples, and x-ray and neutron scattering from unilamellar vesicles at T=30 C. We measured the volume/lipid VL = 1426 1 3. The area/lipid was found to be 80.5 1.5 2 when both x-ray and neutron data were combined with the SDP model analysis (Ku?erka et al., 2008); this is substantially larger than the area of DOPC which has the largest area of the common linear chain lipids. Pf was measured to be 7.0 1.0 10?3 cm/sec; this is considerably smaller than predicted by the recently proposed 3-slab model (Nagle et al., 2008). This disagreement can be understood if there is a diminished diffusion coefficient in the hydrocarbon core of DPhyPC and that is supported by previous molecular dynamics simulations (Shinoda et al., 2004). While the DPhyPC head-head thickness (DHH= 36.4 ), and Hamaker parameter (H=4.5 10?21J) were similar to the linear chain lipid DOPC, the bending modulus (KC=5.2 0.5 10?21J) was 30% smaller. Our results suggest that, from the biophysical perspective, DPhyPC belongs to a different family of lipids than phosphatidylcholines that have linear chain hydrocarbon chains. PMID:20447383

Tristram-Nagle, Stephanie; Kim, Dong Joo; Akhunzada, Nadia; Ku?erka, Norbert; Mathai, John C.; Katsaras, John; Zeidel, Mark; Nagle, John F.

2010-01-01

397

A Biochemical Assay for Acetylcholinesterase Activity in PC12 Cells  

NSDL National Science Digital Library

This lab describes two biochemical assays: One for measuring acetylcholinesterase activity and one for measuring protein concentration. Students learn how to manipulate small-volume samples, use a standard spectrophotometer or a microplate reader spectrophotometer, construct a standard curve, and normalize data. The lab is intended to be used in conjunction with a cell culture lab in which PC12 cells are exposed to various agents that influence their phenotypic state.

Paul J. Schwartz (University of Medicine and Dentistry of New Jersey;Department of Neurological Surgery REV); Jay A. Blundon (Rhodes College;Department of Biology REV); Elizabeth M. Adler (American Association for the Advancement of Science;Science's STKE REV)

2007-07-10

398

The study of space communications spread spectrum systems. Part 1: Saw-based joint group demodulation of frequency shift keyed and differential phase shift keyed signals  

Microsoft Academic Search

A surface acoustic wave (SAW) device based processor, capable of the joint group demodulation of frequency shift keying (FSK) and differential phase shift keying (DPSK) signals, and intended for use in the Canadian extremely high frequency (EHF) Satcom system is proposed. The processor is based on the ability of SAW filters to implement wideband, real time, Fourier transforms with an

Peter T. Traynor; Peter J. McLane

1990-01-01

399

LysoPC acyltransferase/PC transacylase activities in plant plasma membrane and plasma membrane-associated endoplasmic reticulum  

PubMed Central

Background The phospholipids of the plant plasma membrane are synthesized in the endoplasmic reticulum (ER). The majority of these lipids reach the plasma membrane independently of the secretory vesicular pathway. Phospholipid delivery to the mitochondria and chloroplasts of plant cells also bypasses the secretory pathway and here it has been proposed that lysophospholipids are transported at contact sites between specific regions of the ER and the respective organelle, followed by lysophospholipid acylation in the target organelle. To test the hypothesis that a corresponding mechanism operates to transport phospholipids to the plasma membrane outside the secretory pathway, we investigated whether lysolipid acylation occurs also in the plant plasma membrane and whether this membrane, like the chloroplasts and mitochondria, is in close contact with the ER. Results The plant plasma membrane readily incorporated the acyl chain of acyl-CoA into phospholipids. Oleic acid was preferred over palmitic acid as substrate and acyl incorporation occurred predominantly into phosphatidylcholine (PC). Phospholipase A2 stimulated the reaction, as did exogenous lysoPC when administered in above critical micellar concentrations. AgNO3 was inhibitory. The lysophospholipid acylation reaction was higher in a membrane fraction that could be washed off the isolated plasma membranes after repeated freezing and thawing cycles in a medium with lowered pH. This fraction exhibited several ER-like characteristics. When plasma membranes isolated from transgenic Arabidopsis expressing green fluorescent protein in the ER lumen were observed by confocal microscopy, membranes of ER origin were associated with the isolated plasma membranes. Conclusion We conclude that a lysoPC acylation activity is associated with plant plasma membranes and cannot exclude a PC transacylase activity. It is highly plausible that the enzyme(s) resides in a fraction of the ER, closely associated with the plasma membrane, or in both. We suggest that this fraction might be the equivalent of the mitochondria associated membrane of ER origin that delivers phospholipids to the mitochondria, and to the recently isolated ER-derived membrane fraction that is in close contact with chloroplasts. The in situ function of the lysoPC acylation/PC transacylase activity is unknown, but involvement in lipid delivery from the ER to the plasma membrane is suggested. PMID:18045483

Larsson, Karin E; Kjellberg, J Magnus; Tjellstrm, Henrik; Sandelius, Anna Stina

2007-01-01

400

Modulation of total electron content by ULF Pc5 waves  

NASA Astrophysics Data System (ADS)

intriguing effect was found while analyzing the small-scale variations of total electron content (TEC) derived from global positioning system (GPS) signals. We found a response in TEC variations to intense global Pc5 pulsations with periods of a few millihertz covering the corrected geomagnetic latitudes ~58-75 during the recovery phase of the strong magnetic storms on 31 October 2003. Earlier studies demonstrated that the GPS-TEC technique is a powerful method to study the propagation pattern of transient disturbances in the ionosphere, generated by seismic or internal gravity waves. This technique has turned out to be sensitive enough to ULF waves as well. During periods with intense Pc5 geomagnetic wave activity, distinct pulsations with the same periodicity were found in the TEC data from high-latitude GPS receiving stations in Scandinavia. Wavelet and cross-spectral analysis showed a high coherence (~0.9) between the periodic geomagnetic and TEC variations. Moreover, the relative amplitude of TEC periodic fluctuations ?TEC/TEC was about or even larger than the relative amplitude of geomagnetic variations ?B/B. So far, the effect of TEC modulation by Pc5 waves is not well understood and is still a challenge for the MHD wave theory. Various possible modulation mechanisms have been estimated, but no mechanism has been firmly identified.

Pilipenko, V.; Belakhovsky, V.; Murr, D.; Fedorov, E.; Engebretson, M.

2014-06-01

401

Observations of two types of Pc 1-2 pulsations in the outer dayside magnetosphere  

NASA Astrophysics Data System (ADS)

Analysis of high time resolution magnetometer data from the Polar satellite and from an array of high-latitude ground stations in Antarctica has identified 20 simultaneously observed Pc 1-2 wave events in the outer dayside magnetosphere during the first 17 months of Polar operations. In contrast to most earlier satellite studies of Pc 1-2 waves, based on data from equatorial satellites near apogee which moved only slowly across L shells if at all, the initial orbit of Polar allowed it to rapidly cross outer magnetospheric L shells, but significantly away from the magnetic equator. Consistent with several previous studies of outer magnetospheric Pc 1-2 waves, the majority of these events (75%) were associated with significant compressions of the magnetosphere. Seven of the events occurred simultaneously in satellite and ground data, with wave bursts temporally associated with compressions. These events, most at L values > 9, confirm the suggestion of [1993] that the outer dayside magnetosphere is often near marginal stability for electromagnetic ion cyclotron (EMIC) wave generation, so waves can be stimulated by even modest magnetospheric compressions. However, 10 of the wave events (five associated with compressions, and five not) were highly localized in L shell. In these "spatially localized" cases, continuous wave emissions were seen on the ground for extended periods of time, while in space waves were observed for only a few minutes and occurred only in radially narrow regions. The noncompressional events, all spatially localized, appear to be the first examples identified in space of the class of wave events known as Pc 1-2, sustained narrowband emissions which have durations at high-latitude ground stations of the order of 10 hours in the day and dusk local time sectors. All 10 of the spatially localized events, whether compressional or not, followed intervals of at least 12 hours of sustained very quiet magnetospheric conditions. Energetic ion observations from Polar confirm earlier suggestions that drifting plasma sheet ions are the source of dayside Pc 1-2 waves in the outer dayside magnetosphere, but they also show different particle configurations for the spatially localized and temporally ordered event categories. Events in both categories occurred within radially extended regions with ring-like, moderately anisotropic distributions of ?5 keV protons and with deep minima in the flux distributions at energies <5 keV. However, spatially localized wave events occurred only in association with radially localized regions that also contained highly anisotropic fluxes of 0.5-3 keV protons, at a considerable distance from the magnetospheric boundary. In contrast, no such radial structure was evident in any of the temporally ordered events, or in three "uncertain" events. The association of the spatially localized events with highly structured populations of plasma sheet protons of keV and higher energies indicates an important but unanticipated role for these protons in destabilizing plasma in the outer dayside magnetosphere, possibly through increasing the local plasma beta near the magnetic equator.

Engebretson, M. J.; Peterson, W. K.; Posch, J. L.; Klatt, M. R.; Anderson, B. J.; Russell, C. T.; Singer, H. J.; Arnoldy, R. L.; Fukunishi, H.

2002-12-01

402

Polycomb-Group Oncogenes EZH2, BMI1, and RING1 Are Overexpressed in Prostate Cancer With Adverse Pathologic and Clinical Features  

Microsoft Academic Search

ObjectivesPolycomb group (PcG) proteins are involved in maintenance of cell identity and proliferation. The protein EZH2 is overexpressed in disseminated prostate cancer, implicating a role of PcG complexes in tumor progression. In this study, we evaluated the expression of eight members of both PcG complexes in clinicopathologically defined prostate cancer.

Geert J. L. H. van Leenders; Danny Dukers; Daphne Hessels; Susan W. M. van den Kieboom; Christina A. Hulsbergen; J. Alfred Witjes; Arie P. Otte; Chris J. Meijer; Frank M. Raaphorst

2007-01-01

403

DIFFERENTIAL MODULATION OF CATECHOLAMINES BY CHLOROTRIAZINE HERBICIDES IN PHEOCHROMOCYTOMA (PC12) CELLS IN VITRO  

EPA Science Inventory

Differential modulation of catecholamines by chlorotriazine herbicides in pheochromocytoma (PC12) cells in vitro. Das PC, McElroy WK, Cooper RL. Curriculum in Toxicology, University of North Carolina, Chapel Hill 27599, USA. Epidemiological, wildlife, and lab...

404

Molecular Modeling on the PC (by Matthew F. Schlecht)  

NASA Astrophysics Data System (ADS)

"Computeraided molecular modeling doesn't exist for its own sake, but to contribute to scientific endeavor, and enable the scientist to work smarter." This is the last sentence of Schlecht's preface and it says something very important about contemporary scientific research in the academic and industrial venues. Owing to the accelerating improvement in computer technology (hardware and software) and its widespread availability, molecular modeling has become a reliable and important tool in chemical research. Consequently, experimentalists have incorporated molecular modeling techniques in their research, and partnerships with computational chemists have become common. This is a wellorganized and thorough monograph that devotes its attention to one type of molecular modeling, molecular mechanics, and one molecular modeling software package, PCMODEL. Schlecht targets two reader-user groups, the novice and the journeyman modeler, and articulates three goals. He wants to provide the novice with an introduction to molecular mechanics, and after that with some practical examples of the use of empirical force field calculations. His third goal is to provide the journeyman modeler with a reference work that will aid "further study and practice". These are potentially conflicting goals, but Schlecht is, in my opinion, successful because of the way his book is organized. A comprehensive treatment such as this one is not meant to be read from cover to cover, because it is both an exposition of basic principles and a user's manual. Therefore, the novice and the experienced modeler will undoubtedly use this book in different ways. For example, a novice modeler might be advised to read the Preface and Chapter 1, which together provide a broad introduction to the historical development and goals of molecular mechanics. From there the novice could go to Chapter 5 and read section 5.1 on the components of the molecular mechanics force field, which is presented in 22 pages with plenty of graphical support. The reader is now ready to move to Chapter 6 on applications and work through the 32 exercises (Chapters 3 and 4 have an additional 11 exercises) designed to illustrate the current uses of molecular modeling in academic and industrial research. Chapter 3 (Input and Output), Chapter 4 (File Formats), and the balance of Chapter 5 can be consulted as needed. For example, Chapter 5 contains 160 pages on the evolution of the various empirical force fields in use today and important information in each case on parameterization and implementation. Besides finding a clearly written, wellorganized, thorough presentation, the reader will appreciate a number of other important features. There are numerous references (993) to the primary literature covering the field of molecular mechanics from its beginnings to mid1997, when the book went to press. There is a complete glossary of PCMODEL commands, and a comprehensive and valuable glossary (77 pages) of frequently used computer terms. There are 392 figures (many of them screen captures) providing illustrations of the PCMODEL interface in use and examples of input and output files. To aid the reader/user in obtaining expertise as a modeler, a diskette containing all the structure files for all the exercises accompanies the text. In addition, the author provides, on the same diskette, a browserreadable HTML file that contains links to a large number of pertinent resources on the World Wide Web. In summary, Molecular Modeling on the PC, by Matthew Schlecht, is a very impressive contribution to the molecular modeling literature. Schlecht's book should be in every college and university library and in the personal libraries of those who want to learn more about molecular mechanics or who anticipate its use in their teaching or research.

Rioux, Reviewed Frank

2000-06-01

405

An overview of the evaluation plan for PC/MISI: PC-based Multiple Information System Interface  

NASA Technical Reports Server (NTRS)

An initial evaluation plan for the personal computer multiple information system interface (PC/MISI) project is discussed. The document is intend to be used as a blueprint for the evaluation of this system. Each objective of the design project is discussed along with the evaluation parameters and methodology to be used in the evaluation of the implementation's achievement of those objectives. The potential of the system for research activities related to more general aspects of information retrieval is also discussed.

Dominick, Wayne D. (editor); Lim, Bee Lee; Hall, Philip P.

1985-01-01

406

Space transportation alternatives for large space programs - The International Space University summer session - 1992  

Microsoft Academic Search

The issues discussed in this paper are the result of a 10-week study by the Space Solar Power Program design project members and the Space Transportation Group at the International Space University (ISU) summer session of 1992 to investigate new paradigms in space propulsion and how those paradigms might reduce the costs for large space programs. The program plan was

Bryan Palaszewski

1993-01-01

407

NERVE GROWTH FACTOR-INDUCED INCREASE IN SAXITOXIN BINDING TO RAT PC12 PHEOCHROMOCYTOMA CELLS  

Microsoft Academic Search

The PC12 clone is a line of rat pheochromocytoma cells which undergoes neuronal differentiation in the presence of nerve growth factor (NGF) protein. In the absence of NGF, PC12 cells are electrically inexcitable, while after several weeks of NGF treatment, they develop sodium action potentials. The number and density of sodium channels on PC12 cells before and after treatment with

B. RUDY; B. KIRSCHENBAUM; L. A. GREENE

408

King Cobra (Ophiophagus hannah) Venom L-Amino Acid Oxidase Induces Apoptosis in PC-3 Cells and Suppresses PC-3 Solid Tumor Growth in a Tumor Xenograft Mouse Model  

PubMed Central

King cobra (Ophiophagus hannah) venom L-amino acid oxidase (OH-LAAO), a heat stable enzyme, has been shown to exhibit very potent anti-proliferative activity against human breast and lung tumorigenic cells but not in their non-tumorigenic counterparts. We further examine its in vitro and in vivo anti-tumor activity in a human prostate adenocarcinoma (PC-3) model. OH-LAAO demonstrated potent cytotoxicity against PC-3 cells with IC50 of 0.05 g/mL after 72 h incubation in vitro. It induced apoptosis as evidenced with an increase in caspase-3/7 cleavages and an increase in annexin V-stained cells. To examine its in vivo anti-tumor activity, we treated PC-3 tumor xenograft implanted subcutaneously in immunodeficient NU/NU (nude) mice with 1 g/g OH-LAAO given intraperitoneally (i.p.). After 8 weeks of treatment, OH-LAAO treated PC-3 tumors were markedly inhibited, when compared to the control group (P <0.05). TUNEL staining analysis on the tumor sections showed a significantly increase of apoptotic cells in the LAAO-treated animals. Histological examinations of the vital organs in these two groups showed no significant differences with normal tissues, indicating no obvious tissue damage. The treatment also did not cause any significant changes on the body weight of the mice during the duration of the study. These observations suggest that OH-LAAO cytotoxic effects may be specific to tumor xenografts and less to normal organs. Given its potent anti-tumor activities shown in vitro as well as in vivo, the king cobra venom LAAO can potentially be developed to treat prostate cancer and other solid tumors. PMID:24782648

Lee, Mui Li; Fung, Shin Yee; Chung, Ivy; Pailoor, Jayalakshmi; Cheah, Swee Hung; Tan, Nget Hong

2014-01-01

409

King cobra (Ophiophagus hannah) venom L-amino acid oxidase induces apoptosis in PC-3 cells and suppresses PC-3 solid tumor growth in a tumor xenograft mouse model.  

PubMed

King cobra (Ophiophagus hannah) venom L-amino acid oxidase (OH-LAAO), a heat stable enzyme, has been shown to exhibit very potent anti-proliferative activity against human breast and lung tumorigenic cells but not in their non-tumorigenic counterparts. We further examine its in vitro and in vivo anti-tumor activity in a human prostate adenocarcinoma (PC-3) model. OH-LAAO demonstrated potent cytotoxicity against PC-3 cells with IC50 of 0.05 g/mL after 72 h incubation in vitro. It induced apoptosis as evidenced with an increase in caspase-3/7 cleavages and an increase in annexin V-stained cells. To examine its in vivo anti-tumor activity, we treated PC-3 tumor xenograft implanted subcutaneously in immunodeficient NU/NU (nude) mice with 1 g/g OH-LAAO given intraperitoneally (i.p.). After 8 weeks of treatment, OH-LAAO treated PC-3 tumors were markedly inhibited, when compared to the control group (P <0.05). TUNEL staining analysis on the tumor sections showed a significantly increase of apoptotic cells in the LAAO-treated animals. Histological examinations of the vital organs in these two groups showed no significant differences with normal tissues, indicating no obvious tissue damage. The treatment also did not cause any significant changes on the body weight of the mice during the duration of the study. These observations suggest that OH-LAAO cytotoxic effects may be specific to tumor xenografts and less to normal organs. Given its potent anti-tumor activities shown in vitro as well as in vivo, the king cobra venom LAAO can potentially be developed to treat prostate cancer and other solid tumors. PMID:24782648

Lee, Mui Li; Fung, Shin Yee; Chung, Ivy; Pailoor, Jayalakshmi; Cheah, Swee Hung; Tan, Nget Hong

2014-01-01

410

The yeast cyclins Pc16p and Pc17p are involved in the control of glycogen storage by the cyclin-dependent protein kinase Pho85p.  

PubMed

Pho85p is a yeast cyclin-dependent protein kinase (Cdk) that can interact with 10 cyclins (Pcls) to form multiple protein kinases. The functions of most of the Pcls, including Pc16p and Pc17p, are poorly defined. We report here that Pc16p and Pc17p are involved in the metabolism of the branched storage polysaccharide glycogen under certain conditions and deletion of PCL6 and PCL7 restores glycogen accumulation to a snf1 pcl8 pcl10 triple mutant, paradoxically activating both glycogen synthase and phosphorylase. Pho85p thus affects glycogen accumulation through multiple Cdks composed of different cyclin partners. PMID:11602261

Wang, Z; Wilson, W A; Fujino, M A; Roach, P J

2001-10-12

411

Spatial and temporal variability of the dimethylsulfide to chlorophyll ratio in the surface ocean: an assessment based on phytoplankton group dominance determined from space  

NASA Astrophysics Data System (ADS)

Dimethylsulfoniopropionate (DMSP) is produced in surface seawater by phytoplankton. Phytoplankton culture experiments have shown that nanoeucaryotes (NANO) display much higher mean DMSP-to-Carbon or DMSP-to-Chlorophyll (Chl) ratios than Prochlorococcus (PRO), Synechococcus (SYN) or diatoms (DIAT). Moreover, the DMSP-lyase activity of algae which cleaves DMSP into dimethylsulfide (DMS) is even more group specific than DMSP itself. Ship-based observations have shown at limited spatial scales, that sea surface DMS-to-Chl ratios (DMS:Chl) are dependent on the composition of phytoplankton groups. Here we use satellite remote sensing of Chl (from SeaWiFS) and of Phytoplankton Group Dominance (PGD from PHYSAT) with ship-based sea surface DMS concentrations (8 cruises in total) to assess this dependence on an unprecedented spatial scale. PHYSAT provides PGD (either NANO, PRO, SYN, DIAT, Phaeocystis (PHAEO) or coccolithophores (COC)) in each satellite pixel (1/4 horizontal resolution). While there are identification errors in the PHYSAT method, it is important to note that these errors are lowest for NANO PGD which we typify by high DMSP:Chl. In summer, in the Indian sector of the Southern Ocean, we find that mean DMS:Chl associated with NANO + PHAEO and PRO + SYN + DIAT are 13.68.4 mmol g-1 (n=34) and 7.34.8 mmol g-1 (n=24), respectively. That is a statistically significant difference (P<0.001) that is consistent with NANO and PHAEO being relatively high DMSP producers. However, in the western North Atlantic between 40 N and 60 N, we find no significant difference between the same PGD. This is most likely because coccolithophores account for the non-dominant part of the summer phytoplankton assemblages. Meridional distributions at 22 W in the Atlantic, and 95 W and 110 W in the Pacific, both show a marked drop in DMS:Chl near the equator, down to few mmol g-1, yet the basins exhibit different PGD (NANO in the Atlantic, PRO and SYN in the Pacific). In tropical and subtropical Atlantic and Pacific waters away from the equatorial and coastal upwelling, mean DMS:Chl associated with high and low DMSP producers are statistically significantly different, but the difference is opposite of that expected from culture experiments. Hence, in a majority of cases PGD is not of primary importance in controlling DMS:Chl variations. We therefore conclude that water-leaving radiance spectra obtained simultaneously from ocean color sensor measurements of Chl concentrations and dominant phytoplankton groups can not be used to predict global fields of DMS.

Masotti, I.; Belviso, S.; Alvain, S.; Johnson, J. E.; Bates, T. S.; Tortell, P. D.; Kasamatsu, N.; Mongin, M.; Marandino, C. A.; Saltzman, E. S.; Moulin, C.

2010-10-01

412

Minocycline attenuates both OGD-induced HMGB1 release and HMGB1-induced cell death in ischemic neuronal injury in PC12 cells  

SciTech Connect

High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.

Kikuchi, Kiyoshi [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan) [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Department of Neurosurgery, Omuta City General Hospital, 2-19-1 Takarazaka, Omuta-City, Fukuoka 836-8567 (Japan); Kawahara, Ko-ichi; Biswas, Kamal Krishna; Ito, Takashi [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan)] [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Tancharoen, Salunya [Department of Pharmacology, Faculty of Dentistry, Mahidol University, 6 Yothe Rd., Rajthevee Bangkok 10400 (Thailand)] [Department of Pharmacology, Faculty of Dentistry, Mahidol University, 6 Yothe Rd., Rajthevee Bangkok 10400 (Thailand); Morimoto, Yoko [Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan)] [Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Matsuda, Fumiyo [Division of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8560 (Japan)] [Division of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8560 (Japan); Oyama, Yoko; Takenouchi, Kazunori [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan)] [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Miura, Naoki [Laboratory of Veterinary Diagnostic Imaging, Department of Veterinary Medicine, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan)] [Laboratory of Veterinary Diagnostic Imaging, Department of Veterinary Medicine, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Arimura, Noboru; Nawa, Yuko; Meng, Xiaojie; Shrestha, Binita; Arimura, Shinichiro [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan)] [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); and others

2009-07-24

413

Robotics Outreach Group  

NSDL National Science Digital Library

RoboFesta is "a worldwide educational movement that focuses on bringing science and technology to a general audience through widespread public participation in a range of robot competitions." This website provides links and information on the Open University Robotics Outreach Group, which began as a multidisciplinary research group that promoted RoboFesta. Members have posted various resources for students and teachers involved in the project, including a discussion of using the Lego RCX brick and their On-Brick Programmer using leJOS (Java for the RCX) that allows users to write simple, linear programs for the RCX Brick without the need for a PC. Related activities and worksheets are also posted and free to download as part of the Teacher Resource Packs being developed to support the RoboCup Junior robot soccer competition. Other projects such as the Robot Fashion Show and Dinomech, 'Robot' Dinosaurs workshop, are also described.

414

Ecosystem Analysis from Space: Diagnosis of Phytoplankton Functional Groups from Satellite Data and Skill Assessment for Coupled Hydrodynamic-Ecosystem Models  

NASA Astrophysics Data System (ADS)

A suite of empirical and semi-analytic ocean color algorithms were applied to three years of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data from the Gulf of Mexico. Examination of the interdependencies between various ocean color products and their relationships to satellite-retrieved physical variables (sea surface temperature, sea surface height) provided a means to diagnose potential changes in the taxonomic composition and size-structure of the surface phytoplankton community and attendant changes in the upper- ocean thermal structure. The principal method used to discern dominant phytoplankton functional groups was via examination of the satellite-estimated phytoplankton absorption efficiency: the ratio of phytoplankton absorption (443 nm) product to the surface pigment concentration product. The results were used to analyze a model of phytoplankton functional group dynamics for the surface mixed layer. Statistical plots summarizing the root-mean-square-errors and correlation coefficients between the model's results and the satellite-estimated chlorophyll fractionation were used to implement a model skill assessment for a range of potential model parameter settings.

Jolliff, J. K.; Penta, B.; Kindle, J.

2006-12-01

415

Single-Event Upset and Scaling Trends in New Generation of the Commercial SOI PowerPC Microprocessors  

NASA Technical Reports Server (NTRS)

SEU from heavy-ions is measured for SOI PowerPC microprocessors. Results for 0.13 micron PowerPC with 1.1V core voltages increases over 1.3V versions. This suggests that improvement in SEU for scaled devices may be reversed. In recent years there has been interest in the possible use of unhardened commercial microprocessors in space because of their superior performance compared to hardened processors. However, unhardened devices are susceptible to upset from radiation space. More information is needed on how they respond to radiation before they can be used in space. Only a limited number of advanced microprocessors have been subjected to radiation tests, which are designed with lower clock frequencies and higher internal core voltage voltages than recent devices [1-6]. However the trend for commercial Silicon-on-insulator (SOI) microprocessors is to reduce feature size and internal core voltage and increase the clock frequency. Commercial microprocessors with the PowerPC architecture are now available that use partially depleted SOI processes with feature size of 90 nm and internal core voltage as low as 1.0 V and clock frequency in the GHz range. Previously, we reported SEU measurements for SOI commercial PowerPCs with feature size of 0.18 and 0.13 m [7, 8]. The results showed an order of magnitude reduction in saturated cross section compared to CMOS bulk counterparts. This paper examines SEUs in advanced commercial SOI microprocessors, focusing on SEU sensitivity of D-Cache and hangs with feature size and internal core voltage. Results are presented for the Motorola SOI processor with feature sizes of 0.13 microns and internal core voltages of 1.3 and 1.1 V. These results are compared with results for the Motorola SOI processors with feature size of 0.18 microns and internal core voltage of 1.6 and 1.3 V.

Irom, Farokh; Farmanesh, Farhad; Kouba, Coy K.

2006-01-01

416

CLIPS - C LANGUAGE INTEGRATED PRODUCTION SYSTEM (IBM PC VERSION)  

NASA Technical Reports Server (NTRS)

The C Language Integrated Production System, CLIPS, is a shell for developing expert systems. It is designed to allow artificial intelligence research, development, and delivery on conventional computers. The primary design goals for CLIPS are portability, efficiency, and functionality. For these reasons, the program is written in C. CLIPS meets or outperforms most micro- and minicomputer based artificial intelligence tools. CLIPS is a forward chaining rule-based language. The program contains an inference engine and a language syntax that provide a framework for the construction of an expert system. It also includes tools for debugging an application. CLIPS is based on the Rete algorithm, which enables very efficient pattern matching. The collection of conditions and actions to be taken if the conditions are met is constructed into a rule network. As facts are asserted either prior to or during a session, CLIPS pattern-matches the number of fields. Wildcards and variables are supported for both single and multiple fields. CLIPS syntax allows the inclusion of externally defined functions (outside functions which are written in a language other than CLIPS). CLIPS itself can be embedded in a program such that the expert system is available as a simple subroutine call. Advanced features found in CLIPS version 4.3 include an integrated microEMACS editor, the ability to generate C source code from a CLIPS rule base to produce a dedicated executable, binary load and save capabilities for CLIPS rule bases, and the utility program CRSV (Cross-Reference, Style, and Verification) designed to facilitate the development and maintenance of large rule bases. Five machine versions are available. Each machine version includes the source and the executable for that machine. The UNIX version includes the source and binaries for IBM RS/6000, Sun3 series, and Sun4 series computers. The UNIX, DEC VAX, and DEC RISC Workstation versions are line oriented. The PC version and the Macintosh version each contain a windowing variant of CLIPS as well as the standard line oriented version. The mouse/window interface version for the PC works with a Microsoft compatible mouse or without a mouse. This window version uses the proprietary CURSES library for the PC, but a working executable of the window version is provided. The window oriented version for the Macintosh includes a version which uses a full Macintosh-style interface, including an integrated editor. This version allows the user to observe the changing fact base and rule activations in separate windows while a CLIPS program is executing. The IBM PC version is available bundled with CLIPSITS, The CLIPS Intelligent Tutoring System for a special combined price (COS-10025). The goal of CLIPSITS is to provide the student with a tool to practice the syntax and concepts covered in the CLIPS User's Guide. It attempts to provide expert diagnosis and advice during problem solving which is typically not available without an instructor. CLIPSITS is divided into 10 lessons which mirror the first 10 chapters of the CLIPS User's Guide. The program was developed for the IBM PC series with a hard disk. CLIPSITS is also available separately as MSC-21679. The CLIPS program is written in C for interactive execution and has been implemented on an IBM PC computer operating under DOS, a Macintosh and DEC VAX series computers operating under VMS or ULTRIX. The line oriented version should run on any computer system which supports a full (Kernighan and Ritchie) C compiler or the ANSI standard C language. CLIPS was developed in 1986 and Version 4.2 was released in July of 1988. Version 4.3 was released in June of 1989.

Riley, G.

1994-01-01

417

Introduction to Digital Mapping with a PocketPC  

NSDL National Science Digital Library

To illustrate the basics of digital mapping on a PocketPC, I have included one of the projects used in our field course. It covers an area southeast of Buena Vista, Colorado that consists of Precambrian plutonic and metamorphic rocks, Tertiary volcanic rocks, and Quaternary sediments. The project comes in the second week of the course and is the first digital mapping experience for the students. Prior to this, they have been learning to map using traditional methods. The Sugarloaf project consists of base maps and data layers. The inclusion of both aerial photo (USGS DOQQ) and topographic base maps (USGS DRG), allows students to choose which ever map works best for them. The data layers include everything that a field geologist would normally record in his/her field notebook and map: general notes, contacts, and structural data (including oriented symbols on the map). The specific layers in this project are: bedding, contacts, faults, foliations, formations, geology, joints, lineations, and stations. In some layers (e.g., bedding, foliation, lineation, and joint), taping a point on the map opens a dialog box into which you enter data such as strike/dip or plunge/trend. In other layers (e.g., stations), taping a point opens a form for notes. In the contact layer, you draw lines. Editing can be done in the field on your PocketPC or back in camp by downloading the project to a computer. If a project is edited on a computer, the edited version must then be uploaded to the PocketPC for use the next day in the field. Final production of the map is done using ArcView or ArcMap.

Onasch, Charles

418

PC based graphic display real-time particle beam uniformity  

NASA Astrophysics Data System (ADS)

A technique has been developed to support the study of the effects of cosmic rays on integrated circuits. The system is designed to determine the particle distribution across the surface of an integrated circuit accurately while the circuit is bombarded by a particle beam. The system uses photomultiplier tubes, an octal discriminator, a computer-controlled NIM quad counter, and an IBM PC. It provides real-time operator feedback for fast beam tuning and monitors momentary fluctuations in the particle beam. The hardware, software, and system performance are described.

Huebner, M. A.; Malone, C. J.; Smith, L. S.; Soli, G. A.

1989-10-01

419

PC Cluster Machine Equipped with High-Speed Communication Software  

E-print Network

A high performance Beowulf (PC cluster) machine installed with Linux operating system and MPI (Message Passing Interface) for interprocessor communications has been constructed using Gigabit Ethernet and the communication software GAMMA (Genoa Active Message Machine), instead of the standard TCP/IP protocol. Fast C/Fortran compilers have been exploited with the GAMMA communication libraries. This method has eliminated large communication overhead of TCP/IP and resulted in significant increase in the computational performance of real application programs including the first-principle molecular dynamics simulation code. (Keywords: non TCP/IP, active messages, small latency, fast C/Fortran compilers, materials science, first-principle molecular dynamics)

Tanaka, M

2004-01-01

420

A PC-based titrator for flow gradient titrations.  

PubMed

This paper describes a PC (personal computer) based titrator which was developed for gradient flow titrations. Concentration gradients were generated electrolytically or volumetrically in small tubes. Complete titration curves can be recorded on-line and evaluated automatically. The titrator can be used with all liquid flow detectors with low axial dispersion. The titrator was evaluated for the titration of thiosulphate with electrogenerated triiodide and for the titration of ammonia with electrogenerated hypobromite after continuous gas dialytic separation of ammonia from the sample solution. PMID:18924977

Fuhrmann, B; Spohn, U

1993-01-01

421

AKPLOT: A plotter routine for IBM PC, XT and AT  

NASA Technical Reports Server (NTRS)

The AKPLOT software for the IBM PC, XT, and AT is an efficient and versatile tool that allows X-Y plotting of quantitative information. Features include IBM four-color graphics, which combined with 10 different symbols allows 40 different curves on the same grid, shrink or expansion of the graph size, any combination of log and linear X and Y axes, selective plotting from multiple curves of a previous run, interpolation and polynomial least-squares fit with any degree polynomial, and a 90-degree tilt of the entire graph. These options are independent, and can be invoked individually.

Kantak, Anil

1987-01-01

422

Wf/pc Cycle 2 Calib: Measles Monitor  

NASA Astrophysics Data System (ADS)

This program takes "uniform illuminated" pictures of the earth to monitor the measles effect observed in WFPC observations. The goals of this program are: 1. Look for changes in measle numbers/characteristics 2. Have before/after images in place for decontaminations. This program will also build up a high quality flat field. The observations are done only with PC with a frequency of once every two weeks. The sequence (during a single earth occultation) is: F517N+OPEN, F517N+F122M, F517N+OPEN

MacKenty, John

1991-07-01

423

PC analysis of an acousto-ultrasonic signal  

NASA Technical Reports Server (NTRS)

An introduction is given to PC software developed to analyze a digitized signal. The specific way in which the software was implemented and the relative ease with which the same software can be implemented in different systems for various applications are discussed. The basic equations and related theory used in the software are furnished. Specifically, mention is made of signal digitization, dc biasing, Fourier analysis, moment analysis, digital filtering, and transfer functions. Examples of calculations are given to indicate the physical significance of variables calculated from the frequency domain via moment equations.

Kiernan, M. T.; Duke, J. C., Jr.

1988-01-01

424

Application of Field System-FS9 and a PC to Antenna Control Unit interface in Radio Astronomy in Peru  

NASA Astrophysics Data System (ADS)

We are in the process to transform a 32m antenna in Peru, used for telecommunications, into a Radio Telescope to perform Radio Astronomy in Peru. The 32m antenna of Peru constructed by NEC was used for telecommunications with communications satellites at 6 GHz for transmission, and 4 GHz for reception. In collaboration of National Institute of Information and Communications Technology (NICT) Japan, and National Observatory of Japan we developed an Antenna Control System for the 32m antenna in Peru. It is based on the Field System FS9, software released by NASA for VLBI station, and an interface to link PC within FS9 software (PC-FS9) and Antenna Control Unit (ACU) of the 32 meters antenna. The PC-FS9 controls the antenna, commands are translated by interface into control signals compatibles with the ACU using: an I/O digital card with two 20bits ports to read azimuth and elevation angles, one 16bits port for reading status of ACU, one 24bits port to send pulses to start or stop operations of antenna, two channels are analogic outputs to drive the azimuth and elevation motors of the antenna, a LCD display to show the status of interface and error messages, and one serial port for communications with PC-FS9,. The first experiment of the control system was made with 11m parabolic antenna of Kashima Space Research Center (NICT), where we tested the right working of the routines implemented for de FS9 software, and simulations was made with looped data between output and input of the interface, both test were done successfully. With this scientific instrument we will be able to contribute with researching of astrophysics. We expect to into a near future to work at 6.7GHz to study Methanol masers, and higher frequencies with some improvements of the surface of the dish.

Vidal, E. V. S.; Ishitsuka, J. I. I.; Koyama, K. Y.

2006-08-01

425

Electrical properties and conduction mechanism of an organic-modified Au/NiPc/n-InP Schottky barrier diode  

NASA Astrophysics Data System (ADS)

The effect of nickel phthalocyanine (NiPc) organic interlayer on the electronic parameters of Au/n-InP Schottky contacts has been investigated using current-voltage ( I- V) and capacitance-voltage ( C- V) measurements. Measurements showed that the barrier heights and ideality factors are 0.58 eV ( I- V), 0.69 eV( C- V) and 1.32 for Au/n-InP Schottky contact and 0.80 eV ( I- V), 1.12 eV ( C- V) and 1.73 for Au/NiPc/n-InP Schottky contact, respectively. Experimental results show that the interfacial layer of NiPc increases the effective barrier height by the influence of the space charge region of the Au/n-InP Schottky junction. Further, Cheung's and modified Norde functions are used to extract the barrier height, series resistance and ideality factors. The discrepancy between barrier heights estimated from I- V to C- V methods is also explained. Moreover, the energy distribution of interface state density is determined from the forward bias I- V data. Results show that the interface states and series resistance play an important role on electrical properties of the structures studied. The reverse leakage current conduction mechanism is investigated. Results reveal that the Schottky conduction mechanism is found to be dominant in the Au/n-InP Schottky contact. However, in the case of Au/NiPc/n-InP Schottky contact, the Schottky conduction mechanism is found to be dominant in the higher bias region, while Poole-Frenkel conduction is found to be dominant in the lower bias region.

Rajagopal Reddy, V.

2014-09-01

426

Binding to and photo-oxidation of cardiolipin by the phthalocyanine photosensitizer Pc 4  

NASA Astrophysics Data System (ADS)

Cardiolipin is a unique phospholipid of the mitochondrial inner membrane. Its peroxidation correlates with release of cytochrome c and induction of apoptosis. The phthalocyanine photosensitizer Pc 4 binds preferentially to the mitochondria and endoplasmic reticulum. Earlier Frster resonance energy transfer studies showed colocalization of Pc 4 and cardiolipin, which suggests cardiolipin as a target of photodynamic therapy (PDT) with Pc 4. Using liposomes as membrane models, we find that Pc 4 binds to cardiolipin-containing liposomes similarly to those that do not contain cardiolipin. Pc 4 binding is also studied in MCF-7c3 cells and those whose cardiolipin content was reduced by treatment with palmitate. Decreased levels of cardiolipin are quantified by thin-layer chromatography. The similar level of binding of Pc 4 to cells, irrespective of palmitate treatment, supports the lack of specificity of Pc 4 binding. Thus, factors other than cardiolipin are likely responsible for the preferential localization of Pc 4 in mitochondria. Nonetheless, cardiolipin within liposomes is readily oxidized by Pc 4 and light, yielding apparently mono- and dihydroperoxidized cardiolipin. If similar products result from exposure of cells to Pc 4-PDT, they could be part of the early events leading to apoptosis following Pc 4-PDT.

Rodriguez, Myriam E.; Kim, Junhwan; Delos Santos, Grace B.; Azizuddin, Kashif; Berlin, Jeffrey; Anderson, Vernon E.; Kenney, Malcolm E.; Oleinick, Nancy L.

2010-09-01

427

Nasal Associated Lymphoid Tissue of the Syrian Golden Hamster Expresses High Levels of PrPC  

PubMed Central

The key event in the pathogenesis of the transmissible spongiform encephalopathies is a template-dependent misfolding event where an infectious isoform of the prion protein (PrPSc) comes into contact with native prion protein (PrPC) and changes its conformation to PrPSc. In many extraneurally inoculated models of prion disease this PrPC misfolding event occurs in lymphoid tissues prior to neuroinvasion. The primary objective of this study was to compare levels of total PrPC in hamster lymphoid tissues involved in the early pathogenesis of prion disease. Lymphoid tissues were collected from golden Syrian hamsters and Western blot analysis was performed to quantify PrPC levels. PrPC immunohistochemistry (IHC) of paraffin embedded tissue sections was performed to identify PrPC distribution in tissues of the lymphoreticular system. Nasal associated lymphoid tissue contained the highest amount of total PrPC followed by Peyers patches, mesenteric and submandibular lymph nodes, and spleen. The relative levels of PrPC expression in IHC processed tissue correlated strongly with the Western blot data, with high levels of PrPC corresponding with a higher percentage of PrPC positive B cell follicles. High levels of PrPC in lymphoid tissues closely associated with the nasal cavity could contribute to the relative increased efficiency of the nasal route of entry of prions, compared to other routes of infection. PMID:25642714

Clouse, Melissa D.; Shikiya, Ronald A.; Bartz, Jason C.; Kincaid, Anthony E.

2015-01-01

428

corto genetically interacts with PcG and trx-G genes and maintains the anterior boundary of Ultrabithorax expression in Drosophila larvae  

Microsoft Academic Search

In Drosophila melanogaster, segment identity is determined by specific expression of homeotic genes (Hox). The Hox expression pattern is first initiated by gap and pair-rule genes and then maintained by genes of the Polycomb-group (Pc-G) and the trithorax-group (trx-G). The corto gene is a putative regulator of the Hox genes since mutants exhibit homeotic transformations. We show here that, in

A. Lopez; D. Higuet; R. Rosset; J. Deutsch; F. Peronnet

2001-01-01

429

All-trans retinoic acid suppresses apoptosis in PC12 cells injured by oxygen and glucose deprivation via the retinoic acid receptor ? signaling pathway.  

PubMed

Vitamin A (VA) has a number of important biological functions in human growth and development. Previous studies by our group demonstrated that the normal VA levels improved recovery of learning and memory function and decreased apoptosis in rats with hypoxic?ischemic brain damage (HIBD). However, it has not been fully elucidated how VA regulates the apoptosis of neuronal cells. To investigate the anti?apoptotic effect of VA, an invitro oxygen glucose deprivation (OGD) model in PC12 cells was treated with four concentrations of all?trans?retinoic acid (ATRA), an active invivo product of VA. Following invitro OGD injury in PC12 cells, the percentage of apoptosis and the fluorescence intensity of the mitochondrial membrane potential (MMP) were increased in the cells, and the expression levels of B-cell lymphoma-associated X (Bax) were enhanced. ATRA treatment at 2?4mol/l for 24h decreased the percentage of apoptosis and the MMP of the PC12 cells injured by OGD. ATRA at 4mol/l also reduced the expression levels of Bax and enhanced the expression of B-cell lymphoma2. Furthermore, RNA interference with retinoic acid receptor? (RAR?) reversed the observed effect in PC12 cells following ATRA treatment at 4mol/l alone. In conclusion, the present study suggested that treatment with ATRA at 4mol/l suppressed apoptosis of PC12 cells following OGD injury, potentially through regulation of the RAR? signaling pathway. PMID:25231683

Zhang, Xiaojian; Yu, Qin; Jiang, Wei; Bi, Yang; Zhang, Yun; Gong, Min; Wei, Xiaoping; Li, Tingyu; Chen, Jie

2014-11-01

430

The SAND domain protein ULTRAPETALA1 acts as a trithorax group factor to regulate cell fate in plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

During development, trithorax group (trxG) chromatin remodeling complexes counteract repression by Polycomb group (PcG) complexes to sustain active expression of key regulatory genes. Although PcG complexes are well characterized in plants, little is known about trxG activities. Here we demonstrate ...

431

Ionospheric signatures of cusp latitude Pc 3 pulsations  

NASA Technical Reports Server (NTRS)

Search coil magnetometer, riometer, photometer, and ELF-VLF receiver data obtained at South Pole Station and McMurdo, Antarctica during selected days in March and April 1986 are compared. Narrow-band magnetic pulsations in the Pc 3 period range are observed simultaneously at both stations in the dayside sector during times of low IMF cone angle, but are considerably stronger at South Pole, which is located at a latitude near the nominal foot point of the dayside cusp/cleft region. Pulsations in auroral light at 427.8 nm wavelength are often observed with magnetic pulsations at South Pole, but such optical pulsations are not observed at McMurdo. The observations suggest that precipitating magnetosheathlike electrons at nominal dayside cleft latitudes are at times modulated with frequencies similar to those of upstream waves. These particles may play an important role, via modification of ionospheric currents and conductivities, in the transmission of upstream wave signals into the magnetosphere and in the generation of dayside high-latitude Pc 3 pulsations.

Engebretson, M. J.; Anderson, B. J.; Cahill, L. J., Jr.; Arnoldy, R. L.; Rosenberg, T. J.

1990-01-01

432

CAP88-PC Version 4, an updated radionuclide NESHAPS model.  

PubMed

The latest version of the CAP88-PC computer model, Version 4, has many changes and improvements from previous versions. The most significant of these changes from a user perspective are the incorporation of age-dependent radionuclide dose and risk factors for ingestion and inhalation, the increase in the number of included radionuclides, and a change in the file management system used by the program. Other changes less visible to the user include new code architecture, incorporation of numerical solvers for the calculation of radioactive decay chains, including the ingrowth of decay products during air transport and ground surface deposition, enhanced error messages, updated on-line help, and a utility for migrating Version 3 datasets, wind files, and population files to Version 4. The modifications have produced a significant improvement in speed and stability for Version 4 relative to Version 3 and eliminated the solution approximations used in Version 3. The U.S. Environmental Protection Agency has implemented an extensive testing and documentation program for CAP88-PC Version 4 to address user concerns with past versions, resulting in enhanced documentation supporting compatibility with user software quality assurance programs. PMID:23803671

Wood, Raymond; Stuenkel, David; Rosnick, Reid

2013-08-01

433

Real-time holographic video images with commodity PC hardware  

NASA Astrophysics Data System (ADS)

The MIT second-generation holographic video system is a real-time electro-holographic display. The system produces a single-color horizontal parallax only (HPO) holographic image. To reconstruct a three-dimensional image, the display uses a computed fringe pattern with an effective resolution of 256K samples wide by 144 lines high by 8 bits per sample. In this paper we first describe the implementation of a new computational subsystem for the display, replacing custom computing hardware with commodity PC graphics chips, and using OpenGL. We also report the implementation of stereogram computing techniques that employ the PC hardware acceleration to generate and update holographic images at rates of up to two frames per second. These innovations shrink the system"s physical footprint to fit on the table-top and mark the fastest rate at which full computation and update have been achieved on this system to date. Finally we present first results of implementing the Reconfigurable Image Projection (RIP) method of computing high-quality holograms on this new system.

Bove, V. Michael, Jr.; Plesniak, Wendy J.; Quentmeyer, Tyeler; Barabas, James

2005-03-01

434

Commodity clusters: Performance comparison between PC`s and workstations  

SciTech Connect

Workstation clusters were originally developed as a way to leverage the better cost basis of UNIX workstations to perform computations previously handled only by relatively more expensive supercomputers. Commodity workstation clusters take this evolutionary process one step further by replacing equivalent proprietary workstation functionality with less expensive PC technology. As PC technology encroaches on proprietary UNIX workstation vendor markets, these vendors will see a declining share of the overall market. As technology advances continue, the ability to upgrade a workstations performance plays a large role in cost analysis. For example, a major upgrade to a typical UNIX workstation means replacing the whole machine. As major revisions to the UNIX vendor`s product line come out, brand new systems are introduced. IBM compatibles, however, are modular by design, and nothing need to be replaced except the components that are truly improved. The DAISy cluster, for example, is about to undergo a major upgrade from 90MHz Pentiums to 200MHz Pentium Pros. All of the memory -- the system`s largest expense -- and disks, power supply, etc., can be reused. As a result, commodity workstation clusters ought to gain an increasingly large share of the distributed computing market.

Carter, R.; Laroco, J.; Armstrong, R.

1996-03-01

435

EULER-POINCAR Flows on the Loop Bott-Virasoro Group and Space of Tensor Densities and (2 + 1)-DIMENSIONAL Integrable Systems  

NASA Astrophysics Data System (ADS)

Following the work of Ovsienko and Roger ([54]), we study loop Virasoro algebra. Using this algebra, we formulate the Euler-Poincar flows on the coadjoint orbit of loop Virasoro algebra. We show that the Calogero-Bogoyavlenskii-Schiff equation and various other (2 + 1)-dimensional Korteweg-deVries (KdV) type systems follow from this construction. Using the right invariant H1 inner product on the Lie algebra of loop Bott-Virasoro group, we formulate the Euler-Poincar framework of the (2 + 1)-dimensional of the Camassa-Holm equation. This equation appears to be the Camassa-Holm analogue of the Calogero-Bogoyavlenskii-Schiff type (2 + 1)-dimensional KdV equation. We also derive the (2 + 1)-dimensional generalization of the Hunter-Saxton equation. Finally, we give an Euler-Poincar formulation of one-parameter family of (1 + 1)-dimensional partial differential equations, known as the b-field equations. Later, we extend our construction to algebra of loop tensor densities to study the Euler-Poincar framework of the (2 + 1)-dimensional extension of b-field equations.

Guha, Partha

436

COMPPAP - COMPOSITE PLATE BUCKLING ANALYSIS PROGRAM (IBM PC VERSION)  

NASA Technical Reports Server (NTRS)

The Composite Plate Buckling Analysis Program (COMPPAP) was written to help engineers determine buckling loads of orthotropic (or isotropic) irregularly shaped plates without requiring hand calculations from design curves or extensive finite element modeling. COMPPAP is a one element finite element program that utilizes high-order displacement functions. The high order of the displacement functions enables the user to produce results more accurate than traditional h-finite elements. This program uses these high-order displacement functions to perform a plane stress analysis of a general plate followed by a buckling calculation based on the stresses found in the plane stress solution. The current version assumes a flat plate (constant thickness) subject to a constant edge load (normal or shear) on one or more edges. COMPPAP uses the power method to find the eigenvalues of the buckling problem. The power method provides an efficient solution when only one eigenvalue is desired. Once the eigenvalue is found, the eigenvector, which corresponds to the plate buckling mode shape, results as a by-product. A positive feature of the power method is that the dominant eigenvalue is the first found, which is this case is the plate buckling load. The reported eigenvalue expresses a load factor to induce plate buckling. COMPPAP is written in ANSI FORTRAN 77. Two machine versions are available from COSMIC: a PC version (MSC-22428), which is for IBM PC 386 series and higher computers and compatibles running MS-DOS; and a UNIX version (MSC-22286). The distribution medium for both machine versions includes source code for both single and double precision versions of COMPPAP. The PC version includes source code which has been optimized for implementation within DOS memory constraints as well as sample executables for both the single and double precision versions of COMPPAP. The double precision versions of COMPPAP have been successfully implemented on an IBM PC 386 compatible running MS-DOS, a Sun4 series computer running SunOS, an HP-9000 series computer running HP-UX, and a CRAY X-MP series computer running UNICOS. COMPPAP requires 1Mb of RAM and the BLAS and LINPACK math libraries, which are included on the distribution medium. The COMPPAP documentation provides instructions for using the commercial post-processing package PATRAN for graphical interpretation of COMPPAP output. The UNIX version includes two electronic versions of the documentation: one in LaTex format and one in PostScript format. The standard distribution medium for the PC version (MSC-22428) is a 5.25 inch 1.2Mb MS-DOS format diskette. The standard distribution medium for the UNIX version (MSC-22286) is a .25 inch streaming magnetic tape cartridge (Sun QIC-24) in UNIX tar format. For the UNIX version, alternate distribution media and formats are available upon request. COMPPAP was developed in 1992.

Smith, J. P.

1994-01-01

437

Small satellite space operations  

NASA Technical Reports Server (NTRS)

CTA Space Systems has played a premier role in the development of the 'lightsat' programs of the 80's and 90's. The high costs and development times associated with conventional LEO satellite design, fabrication, launch, and operations continue to motivate the development of new methodologies, techniques, and generally low cost and less stringently regulated satellites. These spacecraft employ low power 'lightsat' communications (versus TDRSS for NASA's LEO's) and typically fly missions with payload/experiment suites that can succeed, for example, without heavily redundant backup systems and large infrastructures of personnel and ground support systems. Such small yet adaptable satellites are also typified by their very short contract-to-launch times (often one to two years). This paper reflects several of the methodologies and perspectives of our successful involvement in these innovative programs and suggests how they might relieve NASA's mounting pressures to reduce the cost of both the spacecraft and their companion mission operations. It focuses on the use of adaptable, sufficiently powerful yet inexpensive PC-based ground systems for wide ranging user terminal (UT) applications and master control facilities for mission operations. These systems proved themselves in successfully controlling more than two dozen USAF, USN, and ARPA satellites at CTA/SS. UT versions have linked with both GEO and LEO satellites and functioned autonomously in relay roles often in remote parts of the world. LEO applications particularly illustrate the efficacy of these concepts since a user can easily mount a lightweight antenna, usually an omni or helix with light duty rotors and PC-based drivers. A few feet of coax connected to a small transceiver module (the size of a small PC) and a serial line to an associated PC establishes a communications link and together with the PC constitute a viable ground station. Applications included geomagnetic mapping; spaceborne solid state recorder validation; global store-and-forward data communications for both scientific and military purposes such as Desert Storm; UHF transponder services for both digital data and voice using a constellation; remote sensor monitoring of weather and oceanographic conditions; classified payloads; and UHF spectrum surveillance. Ground processing has been accomplished by automatic unattended or manual operation. Management of multiple assets highlights the relative ease with which two constellations totaling nine satellites were controlled from one system including constellation station keeping. Our experience in small end-to-end systems including concurrent design, development, and testing of the flight and operational ground systems offers low cost approaches to NASA scientific satellite operations of the 1990's.

Reiss, Keith

1994-01-01

438

Bacillus anthracis-like bacteria and other B. cereus group members in a microbial community within the International Space Station: a challenge for rapid and easy molecular detection of virulent B. anthracis.  

PubMed

For some microbial species, such as Bacillus anthracis, the etiologic agent of the disease anthrax, correct detection and identification by molecular methods can be problematic. The detection of virulent B. anthracis is challenging due to multiple virulence markers that need to be present in order for B. anthracis to be virulent and its close relationship to Bacillus cereus and other members of the B. cereus group. This is especially the case in environments where build-up of Bacillus spores can occur and several representatives of the B. cereus group may be present, which increases the chance for false-positives. In this study we show the presence of B. anthracis-like bacteria and other members of the B. cereus group in a microbial community within the human environment of the International Space Station and their preliminary identification by using conventional culturing as well as molecular techniques including 16S rDNA sequencing, PCR and real-time PCR. Our study shows that when monitoring the microbial hygiene in a given human environment, health risk assessment is troublesome in the case of virulent B. anthracis, especially if this should be done with rapid, easy to apply and on-site molecular methods. PMID:24945323

van Tongeren, Sandra P; Roest, Hendrik I J; Degener, John E; Harmsen, Hermie J M

2014-01-01

439

Space Station Human Factors Research Review. Volume 3: Space Station Habitability and Function: Architectural Research  

NASA Technical Reports Server (NTRS)

Articles are presented on a space station architectural elements model study, space station group activities habitability module study, full-scale architectural simulation techniques for space stations, and social factors in space station interiors.

Cohen, Marc M. (editor); Eichold, Alice (editor); Heers, Susan (editor)

1987-01-01

440

Antibiofilm Properties of Silver and Gold Incorporated PU, PCLm, PC and PMMA Nanocomposites under Two Shear Conditions  

PubMed Central

Silver and gold nanoparticles (of average size ?2027 nm) were incorporated in PU (Polyurethane), PCLm (Polycaprolactam), PC (polycarbonate) and PMMA (Polymethylmethaacrylate) by swelling and casting methods under ambient conditions. In the latter method the nanoparticle would be present not only on the surface, but also inside the polymer. These nanoparticles were prepared initially by using a cosolvent, THF. PU and PCLm were dissolved and swollen with THF. PC and PMMA were dissolved in CHCl3 and here the cosolvent, THF, acted as an intermediate between water and CHCl3. FTIR indicated that the interaction between the polymer and the nanoparticle was through the functional group in the polymer. The formation of E.coli biofilm on these nanocomposites under low (in a Drip flow biofilm reactor) and high shear (in a Shaker) conditions indicated that the biofilm growth was higher (twice) in the former than in the latter (ratio of shear force?=?15). A positive correlation between the contact angle (of the virgin surface) and the number of colonies, carbohydrate and protein attached on it were observed. Ag nanocomposites exhibited better antibiofilm properties than Au. Bacterial attachment was highest on PC and least on PU nanocomposite. Casting method appeared to be better than swelling method in reducing the attachment (by a factor of 2). Composites reduced growth of organisms by six orders of magnitude, and protein and carbohydrate by 25 times. This study indicates that these nanocomposites may be suitable for implant applications. PMID:23675476

Sawant, Shilpa N.; Selvaraj, Veerapandian; Prabhawathi, Veluchamy; Doble, Mukesh

2013-01-01

441

Antibiofilm properties of silver and gold incorporated PU, PCLm, PC and PMMA nanocomposites under two shear conditions.  

PubMed

Silver and gold nanoparticles (of average size ?20-27 nm) were incorporated in PU (Polyurethane), PCLm (Polycaprolactam), PC (polycarbonate) and PMMA (Polymethylmethaacrylate) by swelling and casting methods under ambient conditions. In the latter method the nanoparticle would be present not only on the surface, but also inside the polymer. These nanoparticles were prepared initially by using a cosolvent, THF. PU and PCLm were dissolved and swollen with THF. PC and PMMA were dissolved in CHCl? and here the cosolvent, THF, acted as an intermediate between water and CHCl?. FTIR indicated that the interaction between the polymer and the nanoparticle was through the functional group in the polymer. The formation of E.coli biofilm on these nanocomposites under low (in a Drip flow biofilm reactor) and high shear (in a Shaker) conditions indicated that the biofilm growth was higher (twice) in the former than in the latter (ratio of shear force?=?15). A positive correlation between the contact angle (of the virgin surface) and the number of colonies, carbohydrate and protein attached on it were observed. Ag nanocomposites exhibited better antibiofilm properties than Au. Bacterial attachment was highest on PC and least on PU nanocomposite. Casting method appeared to be better than swelling method in reducing the attachment (by a factor of 2). Composites reduced growth of organisms by six orders of magnitude, and protein and carbohydrate by 2-5 times. This study indicates that these nanocomposites may be suitable for implant applications. PMID:23675476

Sawant, Shilpa N; Selvaraj, Veerapandian; Prabhawathi, Veluchamy; Doble, Mukesh

2013-01-01

442

Communication spaces  

PubMed Central

Background and objective Annotations to physical workspaces such as signs and notes are ubiquitous. When densely annotated, work areas become communication spaces. This study aims to characterize the types and purpose of such annotations. Methods A qualitative observational study was undertaken in two wards and the radiology department of a 440-bed metropolitan teaching hospital. Images were purposefully sampled; 39 were analyzed after excluding inferior images. Results Annotation functions included signaling identity, location, capability, status, availability, and operation. They encoded data, rules or procedural descriptions. Most aggregated into groups that either created a workflow by referencing each other, supported a common workflow without reference to each other, or were heterogeneous, referring to many workflows. Higher-level assemblies of such groupings were also observed. Discussion Annotations make visible the gap between work done and the capability of a space to support work. Annotations are repairs of an environment, improving fitness for purpose, fixing inadequacy in design, or meeting emergent needs. Annotations thus record the missing information needed to undertake tasks, typically added post-implemented. Measuring annotation levels post-implementation could help assess the fit of technology to task. Physical and digital spaces could meet broader user needs by formally supporting user customization, programming through annotation. Augmented reality systems could also directly support annotation, addressing existing information gaps, and enhancing work with context sensitive annotation. Conclusions Communication spaces offer a model of how work unfolds. Annotations make visible local adaptation that makes technology fit for purpose post-implementation and suggest an important role for annotatable information systems and digital augmentation of the physical environment. PMID:24005797

Coiera, Enrico

2014-01-01

443

Noninvasive assessment of tissue distribution and tumor pharmacokinetics of Pc 181, a silicon phthalocyanine analogue, in mice  

NASA Astrophysics Data System (ADS)

Objective: In in vitro photodynamic therapy, the LD50 of Pc 181 has been reported to be 7 to 8 times less than that of silicon phthalocyanine 4 (Pc 4). The Optical Pharmacokinetic System (OPS) can measure photosensitizer concentrations in accessible tissues non-invasively. We used OPS to evaluate the tumor pharmacokinetics of Pc 181 and Pc 4 and the tissue drug distribution in SCID mice bearing either human breast cancer MDA-MB-231 or human head and neck squamous cell carcinoma SCC-15 xenografts. Methods: Following iv administration of 2.5 mg/kg Pc 181 or 2 mg/kg Pc 4 to SCID mice, OPS measurements were taken on tumor and normal tissues between 5 and 4320 min in vivo or in situ. Results: Large variations in tumor Pc 181 concentrations were observed among mice. In MDA-MB-231 tumors, the Pc 181 concentration peaked at 240 min, and was retained in the tumor. Tumor Pc 181 concentrations were much less than the tumor Pc 4 concentrations at an equimolar dose. Pc 181 concentrations were the highest in liver, followed by spleen, and kidney. In mice bearing SCC-15 xenografts, skin and underlying tissue Pc 181 concentrations were higher than tumor concentrations at all time points examined. Conclusions: This first Pc 181 pharmacokinetics study described a tissue Pc 181 distribution similar to that of Pc 4. However, tumor Pc 181 concentrations were lower than those of Pc 4 at equimolar doses.

Bai, Lihua; Guo, Jianxia; Clausen, Dana M.; Eiseman, Julie L.

2010-02-01

444

The Polycomb group protein EZH2 directly controls DNA methylation  

Microsoft Academic Search

The establishment and maintenance of epigenetic gene silencing is fundamental to cell determination and function. The essential epigenetic systems involved in heritable repression of gene activity are the Polycomb group (PcG) proteins and the DNA methylation systems. Here we show that the corresponding silencing pathways are mechanistically linked. We find that the PcG protein EZH2 (Enhancer of Zeste homolog 2)

Emmanuelle Vir; Carmen Brenner; Rachel Deplus; Loc Blanchon; Mario Fraga; Cline Didelot; Lluis Morey; Aleyde van Eynde; David Bernard; Jean-Marie Vanderwinden; Mathieu Bollen; Manel Esteller; Luciano di Croce; Yvan de Launoit; Franois Fuks

2006-01-01

445

Postconditioning mitigates cell death following oxygen and glucose deprivation in PC12 cells and forebrain reperfusion injury in rats.  

PubMed

Postconditioning mitigates ischemia-induced cellular damage via a modified reperfusion procedure. Mitochondrial permeability transition (MPT) is an important pathophysiological change in reperfusion injury. This study explores the role of MPT modulation underlying hypoxic postconditioning (HPoC) in PC12 cells and studies the neuroprotective effects of ischemic postconditioning (IPoC) on rats. Oxygen-glucose deprivation (OGD) was performed for 10 hr on PC12 cells. HPoC was induced by three cycles of 10-min reoxygenation/10-min rehypoxia after OGD. The MPT inhibitor N-methyl-4-isoleucine cyclosporine (NIM811) and the MPT inducer carboxyatractyloside (CATR) were administered to selective groups before OGD. Cellular death was evaluated by flow cytometry and Western blot analysis. JC-1 fluorescence signal was used to estimate the mitochondrial membrane potential (??m ). Transient global cerebral ischemia (tGCI) was induced via the two-vessel occlusion and hypotension method in male Sprague Dawley rats. IPoC was induced by three cycles of 10-sec reperfusion/10-sec reocclusion after index ischemia. HPoC and NIM811 administration attenuated cell death, cytochrome c release, and caspase-3 activity and maintained ??m of PC12 cells after OGD. The addition of CATR negated the protection conferred by HPoC. IPoC reduced neuronal degeneration and cytochrome c release and cleaved caspase-9 expression of hippocampal CA1 neurons in rats after tGCI. HPoC protected PC12 cells against OGD by modulating the MPT. IPoC attenuated degeneration of hippocampal neurons after cerebral ischemia. 2014 Wiley Periodicals, Inc. PMID:25082329

Lin, Han-Chen; Narasimhan, Purnima; Liu, Shin-Yun; Chan, Pak H; Lai, I-Rue

2015-01-01

446

Effect of oridonin-mediated hallmark changes on inflammatory pathways in human pancreatic cancer (BxPC-3) cells  

PubMed Central

AIM: To investigate the effect of oridonin on nuclear transcription factors and to study the relationship between biological behavior and inflammatory factors in human pancreatic cancer (BxPC-3) cells. METHODS: BxPC-3 cells were treated with various concentrations of oridonin, and viability curves were generated to test for inhibitory effects of the drug on cells. The expression of cytokines such as interleukin-1? (IL-1?), IL-6, or IL-33 was detected in BxPC-3 cell supernatants using an enzyme-linked immunosorbent assay (ELISA), and the protein expression of nuclear transcription factors including nuclear factor ?B, activating protein-1, signal transducer and activator of transcription 3, bone morphogenetic protein 2, transforming growth factor ?1 and sma and mad homologues in BxPC-3 cells was detected using Western blot. Carcinoma hallmark-related proteins such as survivin, vascular endothelial growth factor, and matrix metallopeptidase 2 were also detected using immunoblotting, and intra-nuclear IL-33 expression was detected using immunofluorescent staining. RESULTS: Treatment with oridonin reduced the viability of BxPC-3 cells in a dose dependent manner. The cells exhibited reduced growth following treatment with 8 ?g/mL oridonin (13.05% 3.21%, P < 0.01), and the highest inhibitory ratio was 90.64% 0.70%, which was achieved with oridonin at a dose of 32 ?g/mL. The IC50 value of oridonin in BxPC-3 cells was 19.32 ?g/mL. ELISA analysis revealed that oridonin down-regulated the inflammatory factors IL-1?, IL-6, and IL-33 in a dose-dependent manner. IL-1? expression was significantly reduced in the 16 and 32 ?g/mL treatment groups compared to the control group (12.97 0.45 pg/mL, 11.17 0.63 pg/mL vs 14.40 0.38 pg/mL, P < 0.01). Similar trends were observed for IL-6 expression, which was significantly reduced in the 16 and 32 ?g/mL treatment groups compared to the control group (4.05 0.14 pg/mL vs 4.45 0.43 pg/mL, P < 0.05; 3.95 0.13 pg/mL vs 4.45 0.43 pg/mL, P < 0.01). IL-33 expression was significantly reduced in the 8, 16, and 32 ?g/mL treatment groups compared to the control group (911.05 14.18 pg/mL vs 945.25 12.09 pg/mL, P < 0.05; 802.70 11.88 pg/mL, 768.54 10.98 pg/mL vs 945.25 12.09 pg/mL, P < 0.01). Western blot and immunofluorescent staining analyses suggested that oridonin changed the hallmarks and regulated the expression of various nuclear transcription factors. CONCLUSION: The results obtained suggest that oridonin alters the hallmarks of pancreatic cancer cells through the regulation of nuclear transcription factors. PMID:25356049

Chen, Ru-Yi; Xu, Bin; Chen, Su-Feng; Chen, Si-Si; Zhang, Ting; Ren, Jun; Xu, Jian

2014-01-01

447

ULTRA-COMPACT DWARFS IN THE FOSSIL GROUP NGC 1132  

SciTech Connect

Eleven ultra-compact dwarf (UCD) and 39 extended star cluster candidates are found to be associated with the galaxy NGC 1132. This giant elliptical galaxy is the remnant of a fossil group. UCD and extended star cluster candidates are identified through the analysis of their structural parameters, colors, spatial distribution, and luminosity using deep Hubble Space Telescope observations in two filters: the F475W (Sloan g) and F850LP (Sloan z). The median effective radius of these UCDs is r{sub h} = 13.0 pc. Two types of UCDs are identified in the vicinity of NGC 1132: one type shares the same color and luminosity as the brightest globular clusters and traces the onset of the mass-size relation. The second kind of UCD is represented by the brightest UCD candidate, an M32-type object, with an effective radius of r{sub h} = 77.1 pc, located at {approx}6.6 kpc from the nucleus of NGC 1132. This UCD candidate is likely the remaining nucleus of a minor merger with the host galaxy. With the exception of a particularly blue UCD candidate, UCDs are found to extend the mass-metallicity relation found in globular clusters to higher luminosities. The results of this work support the growing body of evidence showing that UCDs are not circumscribed to galaxy clusters as previously thought. UCDs are likely to be a common occurrence in all environments. The milder tidal field of a fossil group, when compared to a galaxy cluster, allows UCDs and extended star clusters to survive up to the present time at small galactocentric distances.

Madrid, Juan P. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia)

2011-08-10

448

The structures of marialite (Me[subscript 6]) and meionite (Me[subscript 93]) in space groups P4[subscript 2]/n and I4/m, and the absence of phase transitions in the scapolite series  

SciTech Connect

The crystal structures of marialite (Me{sub 6}) from Badakhshan, Afghanistan and meionite (Me{sub 93}) from Mt. Vesuvius, Italy were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements. Their structures were refined in space groups I4/m and P42/n, and similar results were obtained. The Me{sub 6} sample has a formula Ca{sub 0.24}Na{sub 3.37}K{sub 0.24}[Al{sub 3.16}Si{sub 8.84}O{sub 24}]Cl{sub 0.84}(CO{sub 3}){sub 0.15}, and its unit-cell parameters are a = 12.047555(7), c = 7.563210(6) {angstrom}, and V = 1097.751(1) {angstrom}{sup 3}. The average (T1-O) distances are 1.599(1) {angstrom} in I4/m and 1.600(2) {angstrom} in P4{sub 2}/n, indicating that the T1 site contains only Si atoms. In P4{sub 2}/n, the average distances of (T2-O) = 1.655(2) and (T3-O) = 1.664(2) {angstrom} are distinct and are not equal to each other. However, the mean (T2,3-O) = 1.659(2) {angstrom} in P4{sub 2}/n and is identical to the (T2-O) = 1.659(1) {angstrom} in I4/m. The (M-O) [7] = 2.754(1) {angstrom} (M site is coordinated to seven framework O atoms) and M-A = 2.914(1) {angstrom}; these distances are identical in both space groups. The Me{sub 93} sample has a formula of Na{sub 0.29}Ca{sub 3.76}[Al{sub 5.54}Si{sub 6.46}O{sub 24}]Cl{sub 0.05}(SO{sub 4}){sub 0.02}(CO{sub 3}){sub 0.93}, and its unit-cell parameters are a = 12.19882(1), c = 7.576954(8) {angstrom}, and V = 1127.535(2) {angstrom}{sup 3}. A similar examination of the Me{sub 93} sample also shows that both space groups give similar results; however, the C-O distance is more reasonable in P4{sub 2}/n than in I4/m. Refining the scapolite structure near Me{sub 0} or Me{sub 100} in I4/m forces the T2 and T3 sites (both with multiplicity 8 in P4{sub 2}/n) to be equivalent and form the T2' site (with multiplicity 16 in I4/m), but (T2-O) is not equal to (T3-O) in P4{sub 2}/n. Using different space groups for different regions across the series implies phase transitions, which do not occur in the scapolite series.

Antao, Sytle M.; Hassan, Ishmael (West Indies) [West Indies; (Calgary)

2014-05-28

449