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Sample records for arrows signals

  1. Safety effects of traffic signing for left turn flashing yellow arrow signals.

    PubMed

    Schattler, Kerrie L; Gulla, Cody J; Wallenfang, Travis J; Burdett, Beau A; Lund, Jessica A

    2015-02-01

    In 2010, the left turn flashing yellow arrow (FYA) signal displays were installed at signalized intersections on state routes in the Peoria, Illinois, area. Supplemental traffic signs with text "Left Turn Yield on Flashing Yellow Arrow" were mounted on the mast arm adjacent to the left turn signal at over half of the FYA installations. The purpose of this paper is to present the results of the effectiveness evaluation of the FYA supplemental sign on safety. Analyses are presented on the effects of the FYA supplemental sign for all drivers and a subset of drivers age 65 and older. A crash-based comparison of 164 FYA approaches including 90 approaches with the sign and 74 approaches without the sign showed greater crash reductions when the supplemental FYA sign was present. The results also showed that crashes involving drivers age 65 and older did not experience the same magnitudes of crash reductions as compared to all drivers. The findings of this research indicate that supplemental FYA signs may help in improving safety for left-turning vehicles during the permissive interval. Thus, it is recommended that supplemental signs be used when initially implementing the FYA, and that effort to educate the driving public on new traffic control be made to further improve safety at signalized intersections. PMID:25528438

  2. Cellerator: extending a computer algebra system to include biochemical arrows for signal transduction simulations

    NASA Technical Reports Server (NTRS)

    Shapiro, Bruce E.; Levchenko, Andre; Meyerowitz, Elliot M.; Wold, Barbara J.; Mjolsness, Eric D.

    2003-01-01

    Cellerator describes single and multi-cellular signal transduction networks (STN) with a compact, optionally palette-driven, arrow-based notation to represent biochemical reactions and transcriptional activation. Multi-compartment systems are represented as graphs with STNs embedded in each node. Interactions include mass-action, enzymatic, allosteric and connectionist models. Reactions are translated into differential equations and can be solved numerically to generate predictive time courses or output as systems of equations that can be read by other programs. Cellerator simulations are fully extensible and portable to any operating system that supports Mathematica, and can be indefinitely nested within larger data structures to produce highly scaleable models.

  3. Loss of Tc-arrow and canonical Wnt signaling alters posterior morphology and pair-rule gene expression in the short-germ insect, Tribolium castaneum.

    PubMed

    Bolognesi, Renata; Fischer, Tamara D; Brown, Susan J

    2009-07-01

    Wnt signaling has been implicated in posterior patterning in short-germ insects, including the red flour beetle Tribolium castaneum (Bolognesi et al. Curr Biol 18:1624-1629, 2008b; Angelini and Kaufman Dev Biol 283:409-423, 2005; Miyawaki et al. Mech Dev 121:119-130, 2004). Specifically, depletion of Wnt ligands Tc-Wnt1 and Tc-WntD/8 produces Tribolium embryos lacking abdominal segments. Similar phenotypes are produced by depletion of Tc-porcupine (Tc-porc) or Tc-pangolin (Tc-pan), indicating that the signal is transmitted through the canonical Wnt pathway (Bolognesi et al. Curr Biol 18:1624-1629, 2008b). Here we show that RNAi for the receptor Tc-arrow produced similar truncated phenotypes, providing additional evidence supporting canonical signal transduction. Furthermore, since in Tribolium segments are defined sequentially by a pair-rule gene circuit that, when interrupted, produces truncated phenotypes (Choe et al. Proc Natl Acad Sci U S A 103:6560-6564, 2006), we investigated the relationship between loss of Wnt signaling and this pair-rule gene circuit. After depletion of the receptor Tc-arrow, expression of Tc-Wnt1 was noticeably absent from the growth zone, while Tc-WntD/8 was restricted to a single spot of expression in what remained of the posterior growth zone. The primary pair-rule genes Tc-runt (Tc-run) and Tc-even-skipped (Tc-eve) were expressed normally in the anterior segments, but were reduced to a single spot in the remnants of the posterior growth zone. Thus, expression of pair-rule genes and Tc-WntD/8 are similarly affected by depletion of Wnt signal and disruption of the posterior growth zone. PMID:19705150

  4. Time's Arrows Today

    NASA Astrophysics Data System (ADS)

    Savitt, Steven F.

    1997-06-01

    Introduction; Part I. Cosmology and Time's Arrow: 1. Time, gravity, and quantum mechanics W. Unruh; 2. Cosmology, time's arrow, and that old double standard H. Price; Part II. Quantum Theory and Time's Arrow: 3. Time's arrow and the quantum measurement problem A. Leggett; 4. Time, decoherence, and 'reversible' measurements P. Stamp; 5. Time flows, non-locality, and measurement in quantum mechanics S. McCall; 6. Stochastically branching spacetime topology R. Douglas; Part III. Thermodynamics and Time's Arrow: 7. The elusive object of desire: in pursuit of the kinetic equations and the second law L. Sklar; 8. Time in experience and in theoretical description of the world L. Sklar; 9. When and why does entropy increase? M. Barrett and E. Sober; Part IV. Time Travel and Time's Arrow: 10. Closed causal chains P Horwich; 11. Recent work on time travel J. Earman.

  5. A Computer's Arrow of Time

    NASA Astrophysics Data System (ADS)

    Schulman, L. S.

    2005-12-01

    Some researchers believe that the psychological or consciousness arrow of time is a consequence of the thermodynamic arrow. Some don't. As for many issues in this area, the disagreement revolves about fundamental and undebatable assumptions. As a contribution to this standoff I consider the extent to which a computer---presumably governed by nothing more than the thermodynamic arrow---can be said to possess a psychological arrow. My contention is that the parallels are sufficiently strong as to leave little room for an independent psychological arrow. Reservations are nevertheless expressed on the complete objectivity of the thermodynamic arrow.

  6. Arrows: A Special Case of Graphic Communication.

    ERIC Educational Resources Information Center

    Hardin, Pris

    The purpose of this paper is to examine arrow design in relation to the type of pointing, connecting, or processing involved. Three possible approaches to the investigation of arrows as graphic communication include research: by arrow function, relating message structure to arrow design, and linking user expectations to arrow design. The following…

  7. The Length of Time's Arrow

    SciTech Connect

    Feng, Edward H.; Crooks, Gavin E.

    2008-08-21

    An unresolved problem in physics is how the thermodynamic arrow of time arises from an underlying time reversible dynamics. We contribute to this issue by developing a measure of time-symmetry breaking, and by using the work fluctuation relations, we determine the time asymmetry of recent single molecule RNA unfolding experiments. We define time asymmetry as the Jensen-Shannon divergencebetween trajectory probability distributions of an experiment and its time-reversed conjugate. Among other interesting properties, the length of time's arrow bounds the average dissipation and determines the difficulty of accurately estimating free energy differences in nonequilibrium experiments.

  8. A subquantum arrow of time

    NASA Astrophysics Data System (ADS)

    Nieuwenhuizen, Theo M.

    2014-04-01

    The outcome of a single quantum experiment is unpredictable, except in a pure-state limit. The definite process that takes place in the apparatus may either be intrinsically random or be explainable from a deeper theory. While the first scenario is the standard lore, the latter implies that quantum mechanics is emergent. In that case, it is likely that one has to reconsider radiation by accelerated charges as a physical effect, which thus must be compensated by an energy input. Stochastic electrodynamics, for example, asserts that the vacuum energy arises from classical fluctuations with energy 1/2hslashω per mode. In such theories the stability of the hydrogen ground state will arise from energy input from fluctuations and output by radiation, hence due to an energy throughput. That flux of energy constitutes an arrow of time, which we call the "subquantum arrow of time". It is related to the stability of matter and it is more fundamental than, e.g., the thermodynamic and cosmological arrows.

  9. Arrows in Comprehending and Producing Mechanical Diagrams

    ERIC Educational Resources Information Center

    Heiser, Julie; Tversky, Barbara

    2006-01-01

    Mechanical systems have structural organizations--parts, and their relations--and functional organizations--temporal, dynamic, and causal processes--which can be explained using text or diagrams. Two experiments illustrate the role of arrows in diagrams of mechanical systems. In Experiment 1, people described diagrams with or without arrows,…

  10. Arrow injuries in North East Nigeria.

    PubMed

    Madziga, A G

    2003-06-01

    Arrow injuries are an extinct form of injury in most parts of the developed world but constitute 0.1% of emergency admissions in the University of Maiduguri Teaching Hospital annually. This is a retrospective study of arrow injuries carried out over a ten-year period (1989-1999) in order to study the reasons for its continued incidence the presentation and the experiences in the management of these injuries. There were 73 cases of arrow injuries and were all males with a peak age incidence of 31-40 years of age. Majority were farmers, cattle herdsmen and traders from the northeast region of Nigeria and the neighbouring republic of Cameroon, Chad and Niger. The various reasons for the injuries were armed robbery in 41%, communal clashes 20.5%, dispute between farmers and cattle herdsmen 13%, and cattle theft 8%. Majority were clinically stable on presentation with arrows in the head, neck, chest and abdomen this resulted in various surgical procedures in order to remove the arrows and repair damaged viscera. Unstable presentations resulted in mortalities (4.1%) preoperatively. Wound infection was the most common complication in patients who presented late. Improvements in the socio-economic conditions in the region and legislation on the use of these weapons would reduce the incidence of these injuries. PMID:14529215

  11. Decision Making in the Arrow of Time

    NASA Astrophysics Data System (ADS)

    Roldán, Édgar; Neri, Izaak; Dörpinghaus, Meik; Meyr, Heinrich; Jülicher, Frank

    2015-12-01

    We show that the steady-state entropy production rate of a stochastic process is inversely proportional to the minimal time needed to decide on the direction of the arrow of time. Here we apply Wald's sequential probability ratio test to optimally decide on the direction of time's arrow in stationary Markov processes. Furthermore, the steady-state entropy production rate can be estimated using mean first-passage times of suitable physical variables. We derive a first-passage time fluctuation theorem which implies that the decision time distributions for correct and wrong decisions are equal. Our results are illustrated by numerical simulations of two simple examples of nonequilibrium processes.

  12. Arrow 227: Air transport system design simulation

    NASA Technical Reports Server (NTRS)

    Bontempi, Michael; Bose, Dave; Brophy, Georgeann; Cashin, Timothy; Kanarios, Michael; Ryan, Steve; Peterson, Timothy

    1992-01-01

    The Arrow 227 is a student-designed commercial transport for use in a overnight package delivery network. The major goal of the concept was to provide the delivery service with the greatest potential return on investment. The design objectives of the Arrow 227 were based on three parameters; production cost, payload weight, and aerodynamic efficiency. Low production cost helps to reduce initial investment. Increased payload weight allows for a decrease in flight cycles and, therefore, less fuel consumption than an aircraft carrying less payload weight and requiring more flight cycles. In addition, fewer flight cycles will allow a fleet to last longer. Finally, increased aerodynamic efficiency in the form of high L/D will decrease fuel consumption.

  13. Inhibitory cueing effects following manual and saccadic responses to arrow cues.

    PubMed

    Ding, Yun; He, Tao; Satel, Jason; Wang, Zhiguo

    2016-05-01

    With two cueing tasks, in the present study we examined output-based inhibitory cueing effects (ICEs) with manual responses to arrow targets following manual or saccadic responses to arrow cues. In all experiments, ICEs were observed when manual localization responses were required to both the cues and targets, but only when the cue-target onset asynchrony (CTOA) was 2,000 ms or longer. In contrast, when saccadic responses were made in response to the cues, ICEs were only observed with CTOAs of 2,000 ms or less-and only when an auditory cue-back signal was used. The present study also showed that the magnitude of ICEs following saccadic responses to arrow cues decreased with time, much like traditional inhibition-of-return effects. The magnitude of ICEs following manual responses to arrow cues, however, appeared later in time and had no sign of decreasing even 3 s after cue onset. These findings suggest that ICEs linked to skeletomotor activation do exist and that the ICEs evoked by oculomotor activation can carry over to the skeletomotor system. PMID:26956560

  14. t {r_arrow} cWW and WW {r_arrow} {anti t}c + t{anti c} in extended models

    SciTech Connect

    David Atwood; Marc Sher

    1997-07-01

    Jenkins has pointed out that the process t {r_arrow} cW{sup +}W{sup {minus}}is GIM suppressed in the standard model. In this note, the authors calculate the branching ratio for a wide range of models, in which the decay occurs at tree level through exchange of a scalar, fermion or vector. In the case of scalar exchange, a scalar mass between 2m{sub W} and 200 GeV leads to a resonant enhancement, giving a branching ratio as high as a few tenths of a percent. They then note that all of these models will also allow W{sup +}W{sup {minus}} {r_arrow} {anti t}c + t{anti c}, and they calculate the single-top/single-charm production rate at the LHC. The rates aren't negligibly small, but the background from single-top/single-bottom production will probably swamp the signal.

  15. Arrow poisons in south Asia. Part 1. Arrow poisons in ancient India.

    PubMed

    Bisset, N G; Mazars, G

    1984-10-01

    The use of arrow poisons in ancient India is discussed. While it is possible that Mesolithic hunting communities may have applied poison to their arrows, passages in the Rg Veda and Atharva Veda indicate its use in warfare. The meaning of the word -ala, used in the Rg Veda to denote the poison smeared on the arrowheads, is examined; but the available evidence, while almost certainly excluding a mineral (arsenical) source, does not allow a conclusion to be drawn between an animal and/or plant origin. Certain hymns in the Atharva Veda point to aconite tubers as one source. Later Sanskrit (and Buddhist) literature shows that poisoned arrows continued to be used and that a second source of poison was (putrefying) snakes--a source confirmed by an account in the classical literature of Alexander the Great's campaign in western India. Detailed descriptions of the symptoms and methods of treatment of wounds caused by poisoned arrows are to be found in the Sanskrit medical literature. PMID:6394907

  16. GreenArrow version 1.0

    Energy Science and Technology Software Center (ESTSC)

    2006-03-29

    GreenArrow is a visualization program for displaying directed graphs that can use text in place of lines to represent the edges between nodes. This text can be animated to show the link direction, and allow for more text to be displayed then would normally be allowed. The text is also tapered and arced to show direction. The node labels can be wrapped around the node to avoid label crossing as well. The program is interactive,more » and allows the user to zoom, pan and rotate a graph, as well as manipulate the individual nodes.« less

  17. Arrow of time in string theory

    NASA Astrophysics Data System (ADS)

    McInnes, Brett

    2007-10-01

    Inflation allows the problem of the arrow of time to be understood as a question about the structure of spacetime: why was the intrinsic curvature of the earliest spatial sections so much better behaved than it might have been? This is really just the complement of a more familiar problem: what mechanism prevents the extrinsic curvature of the earliest spatial sections from diverging, as classical general relativity suggests? We argue that the stringy version of “creation from nothing”, sketched by Ooguri, Vafa, and Verlinde, solves both of these problems at once. The argument, while very simple, hinges on some of the deepest theorems in global differential geometry. These results imply that when a spatially toral spacetime is created from nothing, the earliest spatial sections are forced to be [quasi-classically] exactly locally isotropic. This local isotropy, in turn, forces the inflaton into its minimal-entropy state. The theory explains why the arrow does not reverse in black holes or in a cosmic contraction, if any.

  18. Arrows as anchors: Conceptual blending and student use of electric field vector arrows

    NASA Astrophysics Data System (ADS)

    Gire, Elizabeth; Price, Edward

    2013-01-01

    We use the theory of conceptual blending with material anchors to describe how people make meaning of the vector arrows representation of electric fields. We describe this representation as a conceptual blend of a spatial (coordinate) input space and an electric-field-as-arrows space (which itself is a blend of electric field concept with arrows). This representation possesses material features including the use of spatial extent (e.g., distance on paper) to represent the coordinate space and to represent the magnitude of electric field vectors. As a result, this representation supports a geometric interpretation of the electric field, breaking the field into components, and the addition of two fields at a point. The material features also emphasize the spatial relationships between the source(s) and points where the field is represented. However, the material features also necessitate sampling and do not generally support the rapid superposition of two fields at all points. We illustrate this analysis with examples from clinical problem-solving interviews with upper-division physics majors, and interpret students' errors in using this representation as resulting from conflict between the input spaces in the blend.

  19. Avatars and arrows in the brain.

    PubMed

    Catmur, Caroline; Santiesteban, Idalmis; Conway, Jane R; Heyes, Cecilia; Bird, Geoffrey

    2016-05-15

    In this Commentary article we critically assess the claims made by Schurz, Kronbichler, Weissengrubler, Surtees, Samson and Perner (2015) relating to the neural processes underlying theory of mind and visual perspective taking. They attempt to integrate research findings in these two areas of social neuroscience using a perspective taking task contrasting mentalistic agents ('avatars'), with non-mentalistic control stimuli ('arrows'), during functional Magnetic Resonance Imaging. We support this endeavour whole-heartedly, agreeing that the integration of findings in these areas has been neglected in research on the social brain. However, we cannot find among the behavioural or neuroimaging data presented by Schurz et al. evidence supporting their claim of 'implicit mentalizing'-the automatic ascription of mental states to another representing what they can see. Indeed, we suggest that neuroimaging methods may be ill-suited to address the existence of implicit mentalizing, and suggest that approaches utilizing neurostimulation methods are likely to be more successful. PMID:26883064

  20. Adding and subtracting vectors: The problem with the arrow representation

    NASA Astrophysics Data System (ADS)

    Heckler, Andrew F.; Scaife, Thomas M.

    2015-06-01

    A small number of studies have investigated student understanding of vector addition and subtraction in generic or introductory physics contexts, but in almost all cases the questions posed were in the vector arrow representation. In a series of experiments involving over 1000 students and several semesters, we investigated student understanding of vector addition and subtraction in both the arrow and algebraic notation (using i ^, j ^, k ^) in generic mathematical and physics contexts. First, we replicated a number of previous findings of student difficulties in the arrow format and discovered several additional difficulties, including the finding that different relative arrow orientations can prompt different solution paths and different kinds of mistakes, which suggests that students need to practice with a variety of relative orientations. Most importantly, we found that average performance in the i j k format was typically excellent and often much better than performance in the arrow format in either the generic or physics contexts. Further, while we find that the arrow format tends to prompt students to a more physically intuitive solution path, we also find that, when prompted, student solutions in the i j k format also display significant physical insights into the problem. We also find a hierarchy in correct answering between the two formats, with correct answering in the i j k format being more fundamental than for the arrow format. Overall, the results suggest that many student difficulties with these simple vector problems lie with the arrow representation itself. For instruction, these results imply that introducing the i j k notation (or some equivalent) with the arrow notation concurrently may be a very useful way to improve student performance as well as help students to learn physics concepts involving vector addition and subtraction.

  1. Learning about Locomotion Patterns: Effective Use of Multiple Pictures and Motion-Indicating Arrows

    ERIC Educational Resources Information Center

    Imhof, Birgit; Scheiter, Katharina; Edelmann, Jorg; Gerjets, Peter

    2013-01-01

    This study investigated how enriching visualizations with arrows indicating the motion of objects may help in conveying dynamic information: Multiple static-simultaneous visualizations with motion-indicating arrows were compared with either multiple visualizations without arrows or a single visualization with arrows. Seventy-one students were…

  2. Visuospatial Attention Is Guided by Both the Symbolic Value and the Spatial Proximity of Selected Arrows

    ERIC Educational Resources Information Center

    Pratt, Jay; Radulescu, Petre; Guo, Ruo Mu; Hommel, Bernhard

    2010-01-01

    There is considerable evidence that overlearned symbols, especially arrows, can orient attention to peripheral locations. In 2003, Pratt and Hommel showed that when 1 arrow is selected from a set of arrows, based on an attentional control setting for a specific target color, the selected arrow determines the orientation of attention. Recently,…

  3. Relation between the psychological and thermodynamic arrows of time

    NASA Astrophysics Data System (ADS)

    Mlodinow, Leonard; Brun, Todd A.

    2014-05-01

    In this paper we lay out an argument that generically the psychological arrow of time should align with the thermodynamic arrow of time where that arrow is well defined. This argument applies to any physical system that can act as a memory, in the sense of preserving a record of the state of some other system. This result follows from two principles: the robustness of the thermodynamic arrow of time to small perturbations in the state, and the principle that a memory should not have to be fine-tuned to match the state of the system being recorded. This argument applies even if the memory system itself is completely reversible and nondissipative. We make the argument with a paradigmatic system, and then formulate it more broadly for any system that can be considered a memory. We illustrate these principles for a few other example systems and compare our criteria to earlier treatments of this problem.

  4. ARROW (Version 2) Commercial Software Validation and Configuration Control

    SciTech Connect

    HEARD, F.J.

    2000-02-10

    ARROW (Version 2), a compressible flow piping network modeling and analysis computer program from Applied Flow Technology, was installed for use at the U.S. Department of Energy Hanford Site near Richland, Washington.

  5. Charming penguin contributions to B{r_arrow}K{pi}

    SciTech Connect

    Isola, C.; Ladisa, M.; Nardulli, G.; Pham, T. N.; Santorelli, P.

    2001-07-01

    We present calculations of the charming-penguin long-distance contributions to B{r_arrow}K{pi} decays due to intermediate charmed meson states. Our calculation is based on the chiral effective Lagrangian for light and heavy mesons, corrected for the hard pion and kaon momenta. We find that the charming-penguin contributions increase significantly the B{r_arrow}K{pi} decay rates in comparison with the short-distance contributions, giving results in better agreement with experimental data.

  6. Identification of a gravitational arrow of time.

    PubMed

    Barbour, Julian; Koslowski, Tim; Mercati, Flavio

    2014-10-31

    It is widely believed that special initial conditions must be imposed on any time-symmetric law if its solutions are to exhibit behavior of any kind that defines an "arrow of time." We show that this is not so. The simplest nontrivial time-symmetric law that can be used to model a dynamically closed universe is the Newtonian N-body problem with vanishing total energy and angular momentum. Because of special properties of this system (likely to be shared by any law of the Universe), its typical solutions all divide at a uniquely defined point into two halves. In each, a well-defined measure of shape complexity fluctuates but grows irreversibly between rising bounds from that point. Structures that store dynamical information are created as the complexity grows and act as "records." Each solution can be viewed as having a single past and two distinct futures emerging from it. Any internal observer must be in one half of the solution and will only be aware of the records of one branch and deduce a unique past and future direction from inspection of the available records. PMID:25396357

  7. Identification of a Gravitational Arrow of Time

    NASA Astrophysics Data System (ADS)

    Barbour, Julian; Koslowski, Tim; Mercati, Flavio

    2014-10-01

    It is widely believed that special initial conditions must be imposed on any time-symmetric law if its solutions are to exhibit behavior of any kind that defines an "arrow of time." We show that this is not so. The simplest nontrivial time-symmetric law that can be used to model a dynamically closed universe is the Newtonian N -body problem with vanishing total energy and angular momentum. Because of special properties of this system (likely to be shared by any law of the Universe), its typical solutions all divide at a uniquely defined point into two halves. In each, a well-defined measure of shape complexity fluctuates but grows irreversibly between rising bounds from that point. Structures that store dynamical information are created as the complexity grows and act as "records." Each solution can be viewed as having a single past and two distinct futures emerging from it. Any internal observer must be in one half of the solution and will only be aware of the records of one branch and deduce a unique past and future direction from inspection of the available records.

  8. Time asymmetry of probabilities versus relativistic causal structure: an arrow of time.

    PubMed

    Coecke, Bob; Lal, Raymond

    2012-05-18

    There is an incompatibility between the symmetries of causal structure in relativity theory and the signaling abilities of probabilistic devices with inputs and outputs: while time reversal in relativity will not introduce the ability to signal between spacelike separated regions, this is not the case for probabilistic devices with spacelike separated input-output pairs. We explicitly describe a nonsignaling device which becomes a perfect signaling device under time reversal, where time reversal can be conceptualized as playing backwards a videotape of an agent manipulating the device. This leads to an arrow of time that is identifiable when studying the correlations of events for spacelike separated regions. Somewhat surprisingly, although the time reversal of Popescu-Rohrlich boxes also allows agents to signal, it does not yield a perfect signaling device. Finally, we realize time reversal using postselection, which could to lead experimental implementation. PMID:23003129

  9. Maxwell's Demons Everywhere: Evolving Design as the Arrow of Time

    PubMed Central

    Bejan, Adrian

    2014-01-01

    Science holds that the arrow of time in nature is imprinted on one-way (irreversible) phenomena, and is accounted for by the second law of thermodynamics. Here I show that the arrow of time is painted much more visibly on another self-standing phenomenon: the occurrence and change (evolution in time) of flow organization throughout nature, animate and inanimate. This other time arrow has been present in science but not recognized as such since the birth of thermodynamics. It is Maxwell's demon. Translated in macroscopic terms, this is the physics of the phenomenon of design, which is the universal natural tendency of flow systems to evolve into configurations that provide progressively greater access over time, and is summarized as the constructal law of design and evolution in nature. Knowledge is the ability to effect design changes that facilitate human flows on the landscape. Knowledge too flows. PMID:24510201

  10. Time's arrows today. Recent physical and philosophical work on the direction of time.

    NASA Astrophysics Data System (ADS)

    Savitt, S. F.

    Most of the work in this volume, the paperback version of the 1995 edition, was presented at a conference, Vancouver, B.C. (Canada), Jun 1992. The eleven contributions are arranged under the following subject headings: 1. Cosmology and time's arrow (W. Unruh, H. Price). 2. Quantum theory and time's arrow (A. Leggett, P. Stamp, S. McCall, R. Douglas). 3. Thermodynamics and time's arrow (L. Sklar, M. Barrett, E. Sober). 4. Time travel and time's arrow (P. Horwich, J. Earman).

  11. Elliptical Orbit [arrow right] 1/r[superscript 2] Force

    ERIC Educational Resources Information Center

    Prentis, Jeffrey; Fulton, Bryan; Hesse, Carol; Mazzino, Laura

    2007-01-01

    Newton's proof of the connection between elliptical orbits and inverse-square forces ranks among the "top ten" calculations in the history of science. This time-honored calculation is a highlight in an upper-level mechanics course. It would be worthwhile if students in introductory physics could prove the relation "elliptical orbit" [arrow right]…

  12. Adding and Subtracting Vectors: The Problem with the Arrow Representation

    ERIC Educational Resources Information Center

    Heckler, Andrew F.; Scaife, Thomas M.

    2015-01-01

    A small number of studies have investigated student understanding of vector addition and subtraction in generic or introductory physics contexts, but in almost all cases the questions posed were in the vector arrow representation. In a series of experiments involving over 1000 students and several semesters, we investigated student understanding…

  13. Symbol-and-Arrow Diagrams in Teaching Pharmacokinetics.

    ERIC Educational Resources Information Center

    Hayton, William L.

    1990-01-01

    Symbol-and-arrow diagrams are helpful adjuncts to equations derived from pharmacokinetic models. Both show relationships among dependent and independent variables. Diagrams show only qualitative relationships, but clearly show which variables are dependent and which are independent, helping students understand complex but important functional…

  14. Arrow Lakes Reservoir Fertilization Experiment, Technical Report 1999-2004.

    SciTech Connect

    Schindler, E.

    2007-02-01

    The Arrow Lakes food web has been influenced by several anthropogenic stressors during the past 45 years. These include the introduction of mysid shrimp (Mysis relicta) in 1968 and 1974 and the construction of large hydroelectric impoundments in 1969, 1973 and 1983. The construction of the impoundments affected the fish stocks in Upper and Lower Arrow lakes in several ways. The construction of Hugh Keenleyside Dam (1969) resulted in flooding that eliminated an estimated 30% of the available kokanee spawning habitat in Lower Arrow tributaries and at least 20% of spawning habitat in Upper Arrow tributaries. The Mica Dam (1973) contributed to water level fluctuations and blocked upstream migration of all fish species including kokanee. The Revelstoke Dam (1983) flooded 150 km of the mainstem Columbia River and 80 km of tributary streams which were used by kokanee, bull trout, rainbow trout and other species. The construction of upstream dams also resulted in nutrient retention which ultimately reduced reservoir productivity. In Arrow Lakes Reservoir (ALR), nutrients settled out in the Revelstoke and Mica reservoirs, resulting in decreased productivity, a process known as oligotrophication. Kokanee are typically the first species to respond to oligotrophication resulting from aging impoundments. To address the ultra-oligotrophic status of ALR, a bottom-up approach was taken with the addition of nutrients (nitrogen and phosphorus in the form of liquid fertilizer from 1999 to 2004). Two of the main objectives of the experiment were to replace lost nutrients as a result of upstream impoundments and restore productivity in Upper Arrow and to restore kokanee and other sport fish abundance in the reservoir. The bottom-up approach to restoring kokanee in ALR has been successful by replacing nutrients lost as a result of upstream impoundments and has successfully restored the productivity of Upper Arrow. Primary production rates increased, the phytoplankton community responded

  15. Arrows as anchors: An analysis of the material features of electric field vector arrows

    NASA Astrophysics Data System (ADS)

    Gire, Elizabeth; Price, Edward

    2014-12-01

    Representations in physics possess both physical and conceptual aspects that are fundamentally intertwined and can interact to support or hinder sense making and computation. We use distributed cognition and the theory of conceptual blending with material anchors to interpret the roles of conceptual and material features of representations in students' use of representations for computation. We focus on the vector-arrows representation of electric fields and describe this representation as a conceptual blend of electric field concepts, physical space, and the material features of the representation (i.e., the physical writing and the surface upon which it is drawn). In this representation, spatial extent (e.g., distance on paper) is used to represent both distances in coordinate space and magnitudes of electric field vectors. In conceptual blending theory, this conflation is described as a clash between the input spaces in the blend. We explore the benefits and drawbacks of this clash, as well as other features of this representation. This analysis is illustrated with examples from clinical problem-solving interviews with upper-division physics majors. We see that while these intermediate physics students make a variety of errors using this representation, they also use the geometric features of the representation to add electric field contributions and to organize the problem situation productively.

  16. Overview of the Cranked-Arrow Wing Aerodynamics Project International

    NASA Technical Reports Server (NTRS)

    Obara, Clifford J.; Lamar, John E.

    2008-01-01

    This paper provides a brief history of the F-16XL-1 aircraft, its role in the High Speed Research program and how it was morphed into the Cranked Arrow Wing Aerodynamics Project. Various flight, wind-tunnel and Computational Fluid Dynamics data sets were generated as part of the project. These unique and open flight datasets for surface pressures, boundary-layer profiles and skin-friction distributions, along with surface flow data, are described and sample data comparisons given. This is followed by a description of how the project became internationalized to be known as Cranked Arrow Wing Aerodynamics Project International and is concluded by an introduction to the results of a four year computational predictive study of data collected at flight conditions by participating researchers.

  17. Parity Violation in Exclusive B arrow γ Kππ

    NASA Astrophysics Data System (ADS)

    Bornheim, Adolf

    2003-04-01

    We present a study of radiative B meson decays into Kππγ using 13.4 fb-1 of e^+e^- data taken with the CLEO detector near the Υ(4S) resonance. By constructing a parity odd observable from the Kππ we are able to study the polarization of the photon from the radiative B decay. According to the standard model the photon from b arrow sγ (barb arrow barsγ) decays should have left-handed (right-handed) polarization, a prediction untested to date. We employ a maximum likelihood fit method to search for all possible charge combinations of the Kππγ final state in charged and neutral B meson decays and to investigate the photon polarization.

  18. 32. Lighted arrows installed on the handrails, one on the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. Lighted arrows installed on the handrails, one on the south span and one on the north span, used by the bridge operator to visually tell when the both of the spans are down. The walkways are on the western side of the bridge, view is facing southwest. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  19. Transfer entropy in physical systems and the arrow of time.

    PubMed

    Spinney, Richard E; Lizier, Joseph T; Prokopenko, Mikhail

    2016-08-01

    Recent developments have cemented the realization that many concepts and quantities in thermodynamics and information theory are shared. In this paper, we consider a highly relevant quantity in information theory and complex systems, the transfer entropy, and explore its thermodynamic role by considering the implications of time reversal upon it. By doing so we highlight the role of information dynamics on the nuanced question of observer perspective within thermodynamics by relating the temporal irreversibility in the information dynamics to the configurational (or spatial) resolution of the thermodynamics. We then highlight its role in perhaps the most enduring paradox in modern physics, the manifestation of a (thermodynamic) arrow of time. We find that for systems that process information such as those undergoing feedback, a robust arrow of time can be formulated by considering both the apparent physical behavior which leads to conventional entropy production and the information dynamics which leads to a quantity we call the information theoretic arrow of time. We also offer an interpretation in terms of optimal encoding of observed physical behavior. PMID:27627274

  20. Battling Arrow's Paradox to Discover Robust Water Management Alternatives

    NASA Astrophysics Data System (ADS)

    Kasprzyk, J. R.; Reed, P. M.; Hadka, D.

    2013-12-01

    This study explores whether or not Arrow's Impossibility Theorem, a theory of social choice, affects the formulation of water resources systems planning problems. The theorem discusses creating an aggregation function for voters choosing from more than three alternatives for society. The Impossibility Theorem is also called Arrow's Paradox, because when trying to add more voters, a single individual's preference will dictate the optimal group decision. In the context of water resources planning, our study is motivated by recent theoretical work that has generalized the insights for Arrow's Paradox to the design of complex engineered systems. In this framing of the paradox, states of society are equivalent to water planning or design alternatives, and the voters are equivalent to multiple planning objectives (e.g. minimizing cost or maximizing performance). Seen from this point of view, multi-objective water planning problems are functionally equivalent to the social choice problem described above. Traditional solutions to such multi-objective problems aggregate multiple performance measures into a single mathematical objective. The Theorem implies that a subset of performance concerns will inadvertently dictate the overall design evaluations in unpredictable ways using such an aggregation. We suggest that instead of aggregation, an explicit many-objective approach to water planning can help overcome the challenges posed by Arrow's Paradox. Many-objective planning explicitly disaggregates measures of performance while supporting the discovery of the planning tradeoffs, employing multiobjective evolutionary algorithms (MOEAs) to find solutions. Using MOEA-based search to address Arrow's Paradox requires that the MOEAs perform robustly with increasing problem complexity, such as adding additional objectives and/or decisions. This study uses comprehensive diagnostic evaluation of MOEA search performance across multiple problem formulations (both aggregated and many

  1. [Forensic medical assessment of injuries to the human body and clothes caused by a crossbow arrow].

    PubMed

    2011-01-01

    Analysis of the data published in the special literature revealed the lack of information for the objective comprehensive forensic medical evaluation of injuries to the human body and clothes caused by the arrows from different models of crossbows. Morphological characteristics of injuries were shown to strongly depend on the design features of the arrows. This fact can be used to differentiate between injuries inflicted by crossbow arrows and other types of missile weapons. PMID:21866845

  2. Of arrows and flows. Causality, determination, and specificity in the Central Dogma of molecular biology.

    PubMed

    Fantini, Bernardino

    2006-01-01

    From its first proposal, the Central Dogma had a graphical form, complete with arrows of different types, and this form quickly became its standard presentation. In different scientific contexts, arrows have different meanings and in this particular case the arrows indicated the flow of information among different macromolecules. A deeper analysis illustrates that the arrows also imply a causal statement, directly connected to the causal role of genetic information. The author suggests a distinction between two different kinds of causal links, defined as 'physical causality' and 'biological determination', both implied in the production of biological specificity. PMID:18351053

  3. Fundamental Aerodynamic Investigations for Development of Arrow-Stabilized Projectiles

    NASA Technical Reports Server (NTRS)

    Kurzweg, Hermann

    1947-01-01

    The numerous patent applications on arrow-stabilized projectiles indicate that the idea of projectiles without spin is not new, but has appeared in various proposals throughout the last decades. As far as projectiles for subsonic speeds are concerned, suitable shapes have been developed for sometime, for example, numerous grenades. Most of the patent applications, though, are not practicable particularly for projectiles with supersonic speed. This is because the inventor usually does not have any knowledge of aerodynamic flow around the projectile nor any particular understanding of the practical solution. The lack of wind tunnels for the development of projectiles made it necessary to use firing tests for development. These are obviously extremely tedious or expensive and lead almost always to failures. The often expressed opinion that arrow-stabilized projectiles cannot fly supersonically can be traced to this condition. That this is not the case has been shown for the first time by Roechling on long projectiles with foldable fins. Since no aerodynamic investigations were made for the development of these projectiles, only tedious series of firing tests with systematic variation of the fins could lead to satisfactory results. These particular projectiles though have a disadvantage which lies in the nature cf foldable fins. They occasionally do not open uniformly in flight, thus causing unsymmetry in flow and greater scatter. The junctions of fins and body are very bad aerodynamically and increase the drag. It must be possible to develop high-performance arrow-stabilized projectiles based on the aerodynamic research conducted during the last few years at Peenemuende and new construction ideas. Thus the final shape, ready for operational use, could be developed in the wind tunnel without loss of expensive time in firing tests. The principle of arrow-stabilized performance has been applied to a large number of caliburs which were stabilized by various means Most

  4. SCAR arrow-wing active flutter suppression system

    NASA Technical Reports Server (NTRS)

    Gordon, C. K.; Visor, O. E.

    1977-01-01

    The potential performance and direct operating cost benefits of an active flutter suppression system (FSS) for the NASA arrow-wing supersonic cruise configuration were determined. A FSS designed to increase the flutter speed of the baseline airplane 20 percent. A comparison was made of the performance and direct operating cost between the FSS equipped aircraft and a previously defined configuration with structural modifications to provide the same flutter speed. Control system synthesis and evaluation indicated that a FSS could provide the increase in flutter speed without degrading airplane reliability, safety, handling qualities, or ride quality, and without increasing repeated loads or hydraulic and electrical power capacity requirements.

  5. Time arrow is influenced by the dark energy.

    PubMed

    Allahverdyan, A E; Gurzadyan, V G

    2016-05-01

    The arrow of time and the accelerated expansion are two fundamental empirical facts of the universe. We advance the viewpoint that the dark energy (positive cosmological constant) accelerating the expansion of the universe also supports the time asymmetry. It is related to the decay of metastable states under generic perturbations, as we show on example of a microcanonical ensemble. These states will not be metastable without dark energy. The latter also ensures a hyperbolic motion leading to dynamic entropy production with the rate determined by the cosmological constant. PMID:27300848

  6. Measurement of the ratio fracl B(Υ(4S)arrow B^+B^-)l B(Υ(4S)arrow B^0 barB^0)

    NASA Astrophysics Data System (ADS)

    Hadavand, Haleh

    2003-04-01

    The ratio R^+/0=fracl B(Υ(4S) arrow B^+B^-)l B(Υ(4S) arrow B^0 barB^0) is measured with fully reconstructed candidates for B^± arrow J/ψ K^± and B^0 arrow J/ψ K^0S decays. Results are based on a data sample collected with the BaBar detector from 1999 to 2002.

  7. Measurement of the B^+/ B^0 Production Ratio from the Υ(4S) Meson using B^± arrow J/ψ K^± and B^0 arrow J/ψ K^0S decays.

    NASA Astrophysics Data System (ADS)

    Hadavand, Haleh

    2004-05-01

    The ratio R^+/0=fracl B(Υ(4S) arrow B^+ B^-)l B(Υ(4S) arrow B^0 barB^0) is measured with fully reconstructed candidates for B^± arrow J/ψ K^± and B^0 arrow J/ψ K^0S decays. Results are based on a data sample collected with the BaBar detector from 1999 to 2002.

  8. Monosomy 9p24{r_arrow}pter and trisomy 5q31{r_arrow}qter: Case report and review of two cases

    SciTech Connect

    Schimmenti, L.A.; Steinberger, J.; Mammel, M.C.

    1995-05-22

    Partial deletion of the short arm of chromosome 9 (p24{r_arrow}pter) and partial duplication of the long arm of chromosome 5 (q32{r_arrow}qter) were observed in an abnormal boy who died at age 8 weeks of a complex cyanotic cardiac defect. He also had minor anomalies, sagittal craniosynostosis, triphalangeal thumbs, hypospadias, and a bifid scrotum. Two other infants with similar cytogenetic abnormalities were described previously. These patients had severe congenital heart defect, genitourinary anomalies, broad nasal bridge, low hairline, apparently low-set ears, short neck, and triphalangeal thumbs, in common with our patient. We suggest that combined monosomy 9q23,24{r_arrow}pter and trisomy 5q31,32{r_arrow}qter may constitute a clinically recognizable syndrome. 13 refs., 2 figs., 2 tabs.

  9. Search for the flavor changing neutral current B-meson decays B^+arrow μ^+ μ^- K^+ and B^0arrow μ^+ μ^-K^*0 at CDF.

    NASA Astrophysics Data System (ADS)

    Erdmann, Wolfram; Speer, Thomas

    1997-04-01

    We present a search for rare B-meson decays B^+arrow μ^+ μ^- K^+ and B^0arrow μ^+ μ^-K^*0 using data from pbarp collisions at √s = 1.8 TeV recorded with CDF during the 1994 to 95 running period. We set upper limits on BR(B^+arrow μ^+ μ^- K^+) and BR(B^0arrow μ^+ μ^-K^*0). ^ Supported by U.S. DOE DE-AC02-76CH03000. ^*We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Instituto Nazionale di Fisica Nucleare; the Ministry of Education, Science and Culture of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; and the A. P. Sloan Foundation.

  10. Qualitative Differences Between Conscious and Nonconscious Processing? On Inverse Priming Induced by Masked Arrows

    ERIC Educational Resources Information Center

    Verleger, Rolf; Jaskowski, Piotr; Aydemir, Aytac; van der Lubbe, Rob H. J.; Groen, Margriet

    2004-01-01

    In general, both consciously and unconsciously perceived stimuli facilitate responses to following similar stimuli. However, masked arrows delay responses to following arrows. This inverse priming has been ascribed to inhibition of premature motor activation, more recently even to special processing of nonconsciously perceived material. Here,…

  11. New Bouncing Curved Arrow Technique for the Depiction of Organic Mechanisms

    ERIC Educational Resources Information Center

    Straumanis, Andrei R.; Ruder, Suzanne M.

    2009-01-01

    Many students fail to develop a conceptual understanding of organic chemistry. Evidence suggests this failure goes hand-in-hand with a failure to grasp the techniques, meaning, and usefulness of curved arrow notation. Use of curved arrow notation to illustrate electrophilic addition appears to be a critical juncture in student understanding.…

  12. Atypical Visual Orienting to Gaze- and Arrow-Cues in Adults with High Functioning Autism

    ERIC Educational Resources Information Center

    Vlamings, Petra H. J. M.; Stauder, Johannes E. A.; van Son, Ilona A. M.; Mottron, Laurent

    2005-01-01

    The present study investigates visual orienting to directional cues (arrow or eyes) in adults with high functioning autism (n = 19) and age matched controls (n = 19). A choice reaction time paradigm is used in which eye-or arrow direction correctly (congruent) or incorrectly (incongruent) cues target location. In typically developing participants,…

  13. Avatars and arrows: implicit mentalizing or domain-general processing?

    PubMed

    Santiesteban, Idalmis; Catmur, Caroline; Hopkins, Senan Coughlan; Bird, Geoffrey; Heyes, Cecilia

    2014-06-01

    Previous studies using the dot perspective task have shown that adults are slower to verify the number of dots they can see in a picture when a human figure in the picture, an avatar, can see a different number of dots. This "self-consistency effect," which occurs even when the avatar's perspective is formally task-irrelevant, has been interpreted as evidence of implicit mentalizing; that humans can think about the mental states of others via dedicated, automatic processes. We tested this interpretation by giving participants 2 versions of the dot perspective task. In some trials, the avatar was presented as in previous experiments, and in other trials the avatar was replaced by an arrow with similar low-level features. We found self-consistency effects of comparable size in the avatar and arrow conditions, suggesting that self-consistency effects in the dot perspective task are due to domain-general processes such as those that mediate automatic attentional orienting. PMID:24377486

  14. Bell's theorem and the causal arrow of time

    NASA Astrophysics Data System (ADS)

    Argaman, Nathan

    2010-10-01

    Einstein held that the formalism of quantum mechanics involves "spooky actions at a distance." In the 1960s, Bell amplified this by showing that the predictions of quantum mechanics disagree with the results of any locally causal description. It should be appreciated that accepting nonlocal descriptions while retaining causality leads to a clash with relativity. Furthermore, the causal arrow of time by definition contradicts time-reversal symmetry. For these reasons, Wheeler and Feynman, Costa de Beauregard, Cramer, Price, and others have advocated abandoning microscopic causality. In this paper, a simplistic but concrete example of this line of thought is presented, in the form of a retro-causal toy model that is stochastic and provides an appealing description of the quantum correlations discussed by Bell. It is concluded that Einstein's "spooky actions" may occur "in the past" rather than "at a distance," resolving the tension between quantum mechanics and relativity and opening unexplored possibilities for future reformulations of quantum mechanics.

  15. Time's arrow in nephrology: the discovery of the kidney.

    PubMed

    Cameron, J Stewart

    2005-01-01

    Time is a unique dimension of the universe, along with perhaps 10 dimensions of space, according to superstring theory. Our brain and its associated consciousness perceive time as a continuous unidirectional stream. Even though we appear to be able to move freely in three dimensions of space; time's arrow for us points only one way, the present eroding into the future to leave the past behind. For two millennia, time has been likened to a stream or river. In the West, for the past two centuries, time and change have been equated almost automatically with the idea of progress. However, change always brings with it loss as well as gain, and progress is far from inevitable. This remains true in the history of medicine. The history of any subject is full of blind alleys, which, although important at the time, generally become edited out in retrospect. PMID:16180549

  16. Arrow physicians: are economics and medicine philosophically incompatible?

    PubMed

    Tsang, Sandro

    2015-06-01

    Economics is en route to its further expansion in medicine, but many in the medical community remain unconvinced that its impact will be positive. Thus, a philosophical enquiry into the compatibility of economics and medicine is necessary to resolve the disagreements. The fundamental mission of medicine obliges physicians to practise science and compassion to serve the patient's best interests. Conventional (neoclassical) economics assumes that individuals are self-interested and that competitive markets will emerge optimal states. Economics is seemingly incompatible with the emphasis of putting patients' interests first. This idea is refuted by Professor Kenneth Arrow's health economics seminal paper. Arrow emphasizes that medical practice involves agency, knowledge, trust and professionalism, and physician-patient relation critically affects care quality. The term Arrow Physician is used to mean a humanistic carer who has a concern for the patient and acts on the best available evidence with health equity in mind. To make this practice sustainable, implementing appropriate motivations, constitutions and institutions to enable altruistic agency is critical. There is substantial evidence that polycentric governance can encourage building trust and reciprocity, so as to avoid depletion of communal resources. This paper proposes building trusting institutions through granting altruistic physicians adequate autonomy to direct resources based on patients' technical needs. It also summarizes the philosophy bases of medicine and economics. It, therefore, contributes to developing a shared language to facilitate intellectual dialogues, and will encourage trans-disciplinary research into medical practice. This should lead to medicine being reoriented to care for whole persons again. PMID:25850973

  17. The politics of attention contextualized: gaze but not arrow cuing of attention is moderated by political temperament.

    PubMed

    Carraro, Luciana; Dalmaso, Mario; Castelli, Luigi; Galfano, Giovanni

    2015-08-01

    It is known that an averted gaze can trigger shifts of attention in an observer, a phenomenon known as gaze-cuing effect. Recently, Dodd et al. (Atten Percept Psychophys 73:24-29, 2011) have reported a reliable gaze-cuing effect for liberals but not for conservatives. The present study tested whether this result is gaze-specific or extends over nonsocial spatial signals. Conservatives and liberals took part in a spatial-cuing task in which centrally placed gaze and arrow cues, pointing rightward or leftward, were followed by a peripheral onset target requiring a simple detection response. Whereas a reliable cuing effect was present for both gaze and arrow cues in the case of liberals, conservatives showed a reduced cuing response only for gaze cues. These results provide further support for the pattern reported by Dodd et al. (2011) and are consistent with the view that conservatives are less susceptible to the influence of spatial cues provided by other individuals. PMID:26055660

  18. Prospects for observing Higgs in ZH (r-arrow) (nu nubar, l(superscript +)l(superscript -)) b bbar channel at TeV33

    SciTech Connect

    Yao, W.-M.

    1996-10-01

    We report the feasibility study of observing associated production of Higgs and {ital Z{sup 0}} bosons with {ital H} {r_arrow} {ital b{anti b}} and {ital Z{sup 0}} {r_arrow} {ital {nu}{anti {nu}}, l{sup +}l{sup -}} at {radical}{ital s} = 2 TeV high luminosity Tevatron (TeV33). The signature of such decay is a resonance of two {ital b} tagged jets, plus wither large missing {ital E{sub T}} (E{sub T} > 35 GeV) or dilepton pair mass near the {ital Z{sup 0}} mass. The signal and backgrounds are estimated using the CDF II detector configuration and the numbers are cross checked against the existing CDF Run I E{sub T} data. It may be possible to detect a Standard Model Higgs boson mass up to 120 GeV with 30 {ital fb{sup -1}} of integrated luminosity by combining a result with {ital W{sup {+-}}H} {r_arrow} {ital l{sup {+-}} {nu}b{anti b}} channel.

  19. Arrow Lakes Reservoir Fertilization Experiment; Years 4 and 5, Technical Report 2002-2003.

    SciTech Connect

    Schindler, E.

    2007-02-01

    This report presents the fourth and fifth year (2002 and 2003, respectively) of a five-year fertilization experiment on the Arrow Lakes Reservoir. The goal of the experiment was to increase kokanee populations impacted from hydroelectric development on the Arrow Lakes Reservoir. The impacts resulted in declining stocks of kokanee, a native land-locked sockeye salmon (Oncorhynchus nerka), a key species of the ecosystem. Arrow Lakes Reservoir, located in southeastern British Columbia, has undergone experimental fertilization since 1999. It is modeled after the successful Kootenay Lake fertilization experiment. The amount of fertilizer added in 2002 and 2003 was similar to the previous three years. Phosphorus loading from fertilizer was 52.8 metric tons and nitrogen loading from fertilizer was 268 metric tons. As in previous years, fertilizer additions occurred between the end of April and the beginning of September. Surface temperatures were generally warmer in 2003 than in 2002 in the Arrow Lakes Reservoir from May to September. Local tributary flows to Arrow Lakes Reservoir in 2002 and 2003 were generally less than average, however not as low as had occurred in 2001. Water chemistry parameters in select rivers and streams were similar to previous years results, except for dissolved inorganic nitrogen (DIN) concentrations which were significantly less in 2001, 2002 and 2003. The reduced snow pack in 2001 and 2003 would explain the lower concentrations of DIN. The natural load of DIN to the Arrow system ranged from 7200 tonnes in 1997 to 4500 tonnes in 2003; these results coincide with the decrease in DIN measurements from water samples taken in the reservoir during this period. Water chemistry parameters in the reservoir were similar to previous years of study except for a few exceptions. Seasonal averages of total phosphorus ranged from 2.11 to 7.42 {micro}g/L from 1997 through 2003 in the entire reservoir which were indicative of oligo-mesotrophic conditions

  20. Characterization of two exon-skipping mutations (3120G{r_arrow}A, 3600G{r_arrow}A) in the CFTR gene

    SciTech Connect

    Zielendki, J.; Markiewicz, D.; Ainsworth, P.J.

    1994-09-01

    Many different types of mutations have been identified in the CFTR gene in patients with cystic fibrosis. Due to the large size of the gene (230 kb), CF mutations have been primarily detected by genomic DNA analysis. While some of the sequence alterations, such as nonsense and frameshift mutations, provide immediate clues to possible molecular consequence, others such as missense mutations are less apparent in their involvement in the disease. In our systematic scanning of the entire coding regions of the CFTR gene for a group of CF patients carrying unknown mutations, two different G to A substitutions located at the last nucleotide position of an exon were identified in two patients. The first one, 3120G{r_arrow}A, is located in exon 16 and the other one, 3600G{r_arrow}A, in exon 18 of the CFTR gene. Both of them are also located at the third position of the corresponding amino acid codon (CAG and TTC, respectively). As a result, the changes would not affect the encoded amino acids (Glu and Leu, respectively). To demonstrate that these are in fact pathologic mutations, we have investigated the CFTR transcripts in these two patients. The results of RT-PCR analysis revealed that aberrant splicing occurred in both cases: transcripts missing exon 16 and 18 were present in the 2 patients, respectively. No normal product was detectable from the 3120G{r_arrow}A and 3600G{r_arrow}A alleles, suggesting that the normal-sized products were exclusively derived from the {triangle}F508 mutant alleles in both of these patients. Hence, we conclude that both 3120G{r_arrow}A and 3600G{r_arrow}A mutations cause exon-skipping leading to premature termination and truncation of CFTR and that the altered G residue in each of these exons is probably part of the splice donor sequence important for efficient mRNA splicing.

  1. Rare decay {eta}{r_arrow}{pi}{pi}{gamma}{gamma} in chiral perturbation theory

    SciTech Connect

    Knoechlein, G.; Scherer, S.; Drechsel, D.

    1996-04-01

    We investigate the rare radiative {eta} decay modes {eta}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{gamma}{gamma} and {eta}{r_arrow}{pi}{sup 0}{pi}{sup 0}{gamma}{gamma} within the framework of chiral perturbation theory at {ital O}({ital p}{sup 4}). We present photon spectra and partial decay rates for both processes as well as a Dalitz contour plot for the charged decay. {copyright} {ital 1996 The American Physical Society.}

  2. Application of HQET to B {r_arrow} K{sup *} transitions

    SciTech Connect

    W. Roberts; F. Ledroit

    1995-10-01

    The authors examine the measured rates for the decays D {r_arrow} K{sup *}l{nu}, B {r_arrow} K{sup *}{psi}{prime} and B {r_arrow} K{sup *}{gamma} in a number of scenarios, in the framework of the heavy quark effective theory. They attempt to find a scenario in which all of these decays are described by a single set of form factors. Once such a scenario is found, they make predictions for the rare decays B {r_arrow} K{sup *}l{sup +}l{sup {minus}}. While they find that many scenarios can provide adequate descriptions of all the data, somewhat surprisingly, they observe that two popular choices of form factors, namely monopolar forms and exponential forms, exhibit some shortcomings, especially when confronted with polarization observables. They predict Br({anti B}{sup 0} {r_arrow} {anti K}{sup 0}{mu}{sup +}{mu}{sup {minus}}) = 6.4 {+-} 1.0 x 10{sup {minus}7} and Br({anti B}{sup 0} {r_arrow} {anti K}{sup *0}{mu}{sup +}{mu}{sup {minus}}) = 3.8 {+-} 1.3 x 10{sup {minus}6}. They also make predictions for polarization observables in these decays.

  3. Arrows of time in the bouncing universes of the no-boundary quantum state

    NASA Astrophysics Data System (ADS)

    Hartle, James; Hertog, Thomas

    2012-05-01

    We derive the arrows of time of our universe that follow from the no-boundary theory of its quantum state (NBWF) in a minisuperspace model. Arrows of time are viewed four-dimensionally as properties of the four-dimensional Lorentzian histories of the universe. Probabilities for these histories are predicted by the NBWF. For histories with a regular “bounce” at a minimum radius fluctuations are small at the bounce and grow in the direction of expansion on either side. For recollapsing classical histories with big bang and big crunch singularities the fluctuations are small near one singularity and grow through the expansion and recontraction to the other singularity. The arrow of time defined by the growth in fluctuations thus points in one direction over the whole of a recollapsing spacetime but is bidirectional in a bouncing spacetime. We argue that the electromagnetic, thermodynamic, and psychological arrows of time are aligned with the fluctuation arrow. The implications of a bidirectional arrow of time for causality are discussed.

  4. DNA → RNA: What Do Students Think the Arrow Means?

    PubMed Central

    Fisk, J. Nick; Newman, Dina L.

    2014-01-01

    The central dogma of molecular biology, a model that has remained intact for decades, describes the transfer of genetic information from DNA to protein though an RNA intermediate. While recent work has illustrated many exceptions to the central dogma, it is still a common model used to describe and study the relationship between genes and protein products. We investigated understanding of central dogma concepts and found that students are not primed to think about information when presented with the canonical figure of the central dogma. We also uncovered conceptual errors in student interpretation of the meaning of the transcription arrow in the central dogma representation; 36% of students (n = 128; all undergraduate levels) described transcription as a chemical conversion of DNA into RNA or suggested that RNA existed before the process of transcription began. Interviews confirm that students with weak conceptual understanding of information flow find inappropriate meaning in the canonical representation of central dogma. Therefore, we suggest that use of this representation during instruction can be counterproductive unless educators are explicit about the underlying meaning. PMID:26086664

  5. High-resolution {upsilon}{sub OH} = 3{l_arrow}0 and {upsilon}{sub OH} = 4{l_arrow}0 overtone spectroscopy of HOD

    SciTech Connect

    Fair, J.R.; Votava, O.; Nesbitt, D.J.

    1996-12-31

    High-resolution (0.005 cm{sup -1}) IR overtone excitation with an injection seeded optical parametric oscillator (OPO) is used to investigate the spectroscopy of HOD in the {upsilon}{sub OH} = 3{l_arrow}0 region via room temperature photoacoustic detection methods. Comparison of the photoacoustic spectra from an H{sub 2}O/D{sub 2}O/HOD mixture and from pure H{sub 2}O determines the lines corresponding to {upsilon}{sub OH} = 3{l_arrow}0 absorptions in HOD. A prediction of the HOD spectrum in this region is generated from an extrapolation of {upsilon}{sub OH} = 0 and 1 rotational constants and from the {upsilon}{sub OH} = 3{l_arrow}0 band origin calculated by Tennyson and coworkers [private communication]. This predicted spectrum enables the HOD {upsilon}{sub OH} = 3{l_arrow}0 photoacoustic spectrum to be assigned; a fit of the experimental data produces the low-order rotational constants for this transition as well as a Birge-Sponer analysis of the overtone series. The vibrational dependence of the HOD rotational constants is demonstrated to be quite linear in {upsilon}{sub OH}, permitting reliable extrapolation to the {upsilon}{sub OH} = 4 manifold. As a result, the {upsilon}{sub OH} = 0, 1 and 3 constants can be used to predict the spectrum of HOD {upsilon}{sub OH} = 4{l_arrow}0, which now enables the assignment of the vibrationally mediated photodissociation spectrum measured by Crim and coworkers. The overtone spectroscopic data for HOD is further confirmed in double resonance IR and UV photolysis of HOD and HOD-containing clusters in slit supersonic expansions.

  6. Spectrum of the elimination of loops and multiple arrows in coupled cell networks

    NASA Astrophysics Data System (ADS)

    Dias, A. P. S.; Moreira, C. S.

    2012-11-01

    A uniform lift of a given network is a network with no loops and no multiple arrows that admits the first network as quotient. Given a regular network (in which all cells have the same type and receive the same number of inputs and all arrows have the same type) with loops or multiple arrows, we prove that it is always possible to construct a uniform lift whose adjacency matrix has only two possible eigenvalues, namely, 0 and -1, in addition to all eigenvalues of the initial network adjacency matrix. Moreover, this uniform lift has the minimal number of cells over all uniform lifts. We also prove that if a non-vanishing eigenvalue of the initial adjacency matrix is fixed then it is always possible to construct a uniform lift that preserves the number of eigenvalues with the same real part of that eigenvalue. Finally, for the eigenvalue zero we show that such a construction is not always possible proving that there are networks with multiple arrows whose uniform lifts all have the eigenvalue 0, in addition to all eigenvalues of the initial network adjacency matrix. Using the concept of ODE-equivalence, we prove then that it is always possible to study a degenerate bifurcation arising in a system whose regular network has multiple arrows as a bifurcation of a bigger system associated with a regular uniform network.

  7. Expression pattern of the Brachyury gene in the arrow worm paraspadella gotoi (chaetognatha).

    PubMed

    Takada, Norio; Goto, Taichiro; Satoh, Nori

    2002-03-01

    Arrow worms (the phylum Chaetognatha), which are among the major marine planktonic animals, are direct developers and exhibit features characteristic of both deuterostomes and protostomes. In particular, the embryonic development of arrow worms appears to be of the deuterostome type. Brachyury functions critically in the formation of the notochord in chordates, whereas the gene is expressed in both the blastopore and stomodeum invagination regions in embryos of hemichordates and echinoderms. Here we analyzed the expression of Brachyury (Pg-Bra) in the arrow worm Paraspadella gotoi and showed that Pg-Bra is expressed in the blastopore region and the stomodeum region in the embryo and then around the mouth opening region at the time of hatching. The expression of Pg-Bra in the embryo resembles that of Brachyury in embryos of hemichordates and echinoderms, whereas that in the mouth opening region in the hatchling appears to be novel. PMID:11892013

  8. Electrophysiological responses to violations of expectation from eye gaze and arrow cues.

    PubMed

    Tipples, Jason; Johnston, Pat; Mayes, Angela

    2013-06-01

    Isolating processes within the brain that are specific to human behavior is a key goal for social neuroscience. The current research was an attempt to test whether recent findings of enhanced negative ERPs in response to unexpected human gaze are unique to eye gaze stimuli by comparing the effects of gaze cues with the effects of an arrow cue. ERPs were recorded while participants (N = 30) observed a virtual actor or an arrow that gazed (or pointed) either toward (object congruent) or away from (object incongruent) a flashing checkerboard. An enhanced negative ERP (N300) in response to object incongruent compared to object congruent trials was recorded for both eye gaze and arrow stimuli. The findings are interpreted as reflecting a domain general mechanism for detecting unexpected events. PMID:22345367

  9. Arrow-Elicited Cueing Effects at Short Intervals: Rapid Attentional Orienting or Cue-Target Stimulus Conflict?

    ERIC Educational Resources Information Center

    Green, Jessica J.; Woldorff, Marty G.

    2012-01-01

    The observation of cueing effects (faster responses for cued than uncued targets) rapidly following centrally-presented arrows has led to the suggestion that arrows trigger rapid automatic shifts of spatial attention. However, these effects have primarily been observed during easy target-detection tasks when both cue and target remain on the…

  10. Penetrating neck injury by an arrow: a paradigm of age old assault.

    PubMed

    Nepal, A; Joshi, R R; Bhandary, S; Mathur, N N; Roka, Y B; Yadav, R

    2010-03-01

    Penetrating neck injuries by traditional weapons are rare entity in the modern era of sophisticated weapons. We report an unusual case of penetrating neck injury by a metallic arrow entering anterior neck in zone II and its tip coming out of neck posteriorly causing difficulty for patient to lie down as well as posing challenge to intubate. Arrows are low velocity projectile and from a close proximity they can cause penetrating trauma similar to a low powered handgun. Management of the case was discussed. PMID:20677615

  11. Parametric flutter studies of an arrow-wing configuration: Some early results

    NASA Technical Reports Server (NTRS)

    Durham, Michael H.; Cole, Stanley R.; Cazier, F. W., Jr.; Keller, Donald F.; Parker, Ellen C.; Wilkie, W. Keats

    1988-01-01

    Some early experimental results from a combined experimental and analytical study being conducted at NASA-Langley of the transonic flutter characterisitics of a generic arrow wing configuration are presented. The planned study includes the parametric variation of a variety of structural and geometric characteristics. Presented here are flutter results of the basic arrow wing, for the basic wing with the addition of two simulated lower-surface-mounted engine nacelles, and for the basic wing with the addition of both the fin and the engine nacelles.

  12. Evidence for the Decay K{sup +}{r_arrow}{pi}{sup +}{nu}{bar v}

    SciTech Connect

    Adler, S.; Atiya, M.S.; Chiang, I.; Diwan, M.V.; Frank, J.S.; Haggerty, J.S.; Kettell, S.H.; Kycia, T.F.; Li, K.K.; Littenberg, L.S.; Ng, C.; Sambamurti, A.; Stevens, A.; Strand, R.C.; Witzig, C.; Komatsubara, T.K.; Kuriki, M.; Muramatsu, N.; Sugimoto, S.; Inagaki, T.; Kabe, S.; Kobayashi, M.; Kuno, Y.; Sato, T.; Shinkawa, T.; Yoshimura, Y.; Kishi, Y.; Nakano, T.; Ardebili, M.; Bazarko, A.O.; Convery, M.R.; Ito, M.M.; Marlow, D.R.; McPherson, R.A.; Meyers, P.D.; Shoemaker, F.C.; Smith, A.J.; Stone, J.R.; Aoki, M.; Blackmore, E.W.; Bergbusch, P.C.; Bryman, D.A.; Konaka, A.; Macdonald, J.A.; Mildenberger, J.; Numao, T.; Padley, P.; Poutissou, J.; Poutissou, R.; Redlinger, G.; Roy, J.; Turcot, A.S.; Kitching, P.; Soluk, R.

    1997-09-01

    An event consistent with the signature expected for the rare kaon decay K{sup +}{r_arrow}{pi}{sup +}{nu}{bar {nu}} has been observed. In the pion momentum region examined, 211{lt}P{lt}230 MeV/c , the backgrounds are estimated to contribute 0.08{plus_minus}0.03 events. If the event is due to K{sup +}{r_arrow}{pi}{sup +}{nu}{bar {nu}} , the branching ratio is 4.2{sup +9.7}{sub {minus}3.5}{times}10{sup {minus}10} . {copyright} {ital 1997} {ital The American Physical Society}

  13. A Couple of "Lim (h[right arrow]0)-Is-Missing" Problems

    ERIC Educational Resources Information Center

    Lau, Ko Hin

    2007-01-01

    Since most students "hate" the concept of limit, in order to make them "happier," this article suggests a couple of naive "lim (h[right arrow]0)-is-missing" problems for them to try for fun. Indeed, differential functional equations that are related to difference quotients in calculus are studied in this paper. In particular, two interesting…

  14. Hollywood Addresses Postwar Assimilation: Indian/White Attitudes in "Broken Arrow."

    ERIC Educational Resources Information Center

    Aleiss, Angela

    1987-01-01

    Examines Western films in context of post-World War II attitudes regarding racial equality. Film "Broken Arrow" and Eliott Arnold's novel "Blood Brother," both recounting story of Apache chief Cochise, examined as benchmark works in national racial attitudes. Films generally seen as supporting Indian assimilation into White culture. (TES)

  15. How Do Selected Arrows Guide Visuospatial Attention? Dissociating Symbolic Value and Spatial Proximity

    ERIC Educational Resources Information Center

    Leblanc, Emilie; Jolicoeur, Pierre

    2010-01-01

    Previous research on the control of visuospatial attention showed that overlearned symbols like arrows have the potential to induce involuntary shifts of attention. Following work on the role of attentional control settings and of the content of working memory in the involuntary deployment of visuospatial attention, Pratt and Hommel (2003) found…

  16. Making Sense of the Arrow-Pushing Formalism among Chemistry Majors Enrolled in Organic Chemistry

    ERIC Educational Resources Information Center

    Ferguson, Robert; Bodner, George M.

    2008-01-01

    This paper reports results of a qualitative study of sixteen students enrolled in a second year organic chemistry course for chemistry and chemical engineering majors. The focus of the study was student use of the arrow-pushing formalism that plays a central role in both the teaching and practice of organic chemistry. The goal of the study was to…

  17. The Effect of Arrow Diagrams on Achievement in Applying the Chain Rule

    ERIC Educational Resources Information Center

    Uygur, Tangul; Ozdas, Aynur

    2007-01-01

    In this study the effectiveness of an arrow diagram which can help students apply the Chain Rule was investigated. Different variations of this diagram were used as mnemonic devices for applying the Chain Rule. For the investigation two instruments were developed, diagnostic test and post-test. The diagnostic test was developed to determine the…

  18. Six Impossible Mechanisms before Breakfast: Arrow Pushing as an Instructional Device in Inorganic Chemistry

    ERIC Educational Resources Information Center

    Berg, Steffen; Ghosh, Abhik

    2013-01-01

    In a recent article by the authors, the suggestion was made that arrow pushing, a widely used tool in organic chemistry, could also be profitably employed in the teaching of introductory inorganic chemistry. A number of relatively simple reactions were used to illustrate this thesis, raising the question whether the same approach might rationalize…

  19. Decorating with Arrows: Toward the Development of Representational Competence in Organic Chemistry

    ERIC Educational Resources Information Center

    Grove, Nathaniel P.; Cooper, Melanie M.; Rush, Kelli M.

    2012-01-01

    Much effort has been expended in developing improved methods for presenting mechanistic thinking and the curved-arrow notation to organic chemistry students; however, most of these techniques are not research-based. The little research that has been conducted has mainly focused on understanding the meaning that students associate with the…

  20. Reflexive Orienting in Response to Eye Gaze and an Arrow in Children with and without Autism

    ERIC Educational Resources Information Center

    Senju, Atsushi; Tojo, Yoshikuni; Dairoku, Hitoshi; Hasegawa, Toshikazu

    2004-01-01

    Background: This study investigated whether another person's social attention, specifically the direction of their eye gaze, and a non-social directional cue, an arrow, triggered reflexive orienting in children with and without autism in an experimental situation. Methods: Children with autism and typically developed children participated in one…

  1. Eye Gaze versus Arrows as Spatial Cues: Two Qualitatively Different Modes of Attentional Selection

    ERIC Educational Resources Information Center

    Marotta, Andrea; Lupianez, Juan; Martella, Diana; Casagrande, Maria

    2012-01-01

    This study aimed to evaluate the type of attentional selection (location- and/or object-based) triggered by two different types of central noninformative cues: eye gaze and arrows. Two rectangular objects were presented in the visual field, and subjects' attention was directed to the end of a rectangle via the observation of noninformative…

  2. Ballistic parameters and trauma potential of carbon dioxide-actuated arrow pistols.

    PubMed

    Nguyen, Tien Thanh; Grossjohann, Rico; Ekkernkamp, Axel; Bockholdt, Britta; Frank, Matthias

    2015-05-01

    Medical literature abounds with reports of injuries and fatalities caused by arrows and crossbow bolts. Crossbows are of particular forensic and traumatological interest, because their mode of construction allows for temporary mechanical storage of energy. A newly developed type of pistol (Arcus Arrowstar), which belongs to the category of air and carbon dioxide weapons, discharges arrow-shaped bolts actuated by carbon dioxide cylinders. As, to the best of the authors' knowledge, literature contains no information on this uncommon subclass of weapons it is the aim of this work to provide the experimental data and to assess the trauma potential of these projectiles based on the ascertained physical parameters. Basic kinetic parameters of these carbon dioxide-actuated bolts (velocity v = 39 m/s, energy E = 7.2 J, energy density E' = 0.26 J/mm(2)) are similar to bolts discharged by pistol crossbows. Subsequent firing resulted in a continuous and fast decrease in kinetic energy of the arrows. Test shots into ballistic soap blocks reveal a high penetration capacity, especially when compared to conventional projectiles of equal kinetic energy values (like, e.g., airgun pellets). To conclude, these data demonstrate the high efficiency of arrow-shaped projectiles, which are also characterized by a high cross-sectional density (ratio of mass to cross-sectional area of a projectile). PMID:25246008

  3. Design, fabrication, and characterization of Si-based ARROW photonic crystal bend waveguides and power splitters.

    PubMed

    Chen, Jian-Hua; Huang, Yang-Tung; Yang, Yu-Lin; Lu, Ming-Feng; Shieh, Jia-Min

    2012-08-20

    Silicon-based (Si-based) photonic crystal waveguide based on antiresonant reflecting optical waveguide (ARROW PCW) structures consisting of 60° bends and Y-branch power splitters were designed and first efficiently fabricated and characterized. The ARROW structure has a relatively large core size suitable for efficient coupling with a single-mode fiber. Simple capsule-shaped topography defects at 60° photonic crystal (PC) bend corners and Y-branch PC power splitters were used for increasing the broadband light transmission. In the preliminary measurements, the propagation losses of the ARROW PC straight waveguides lower than 2 dB/mm with a long length of 1500 μm were achieved. The average bend loss of 60° PC bend waveguides was lower than 3 dB/bend. For the Y-branch PC power splitters, the average power imbalance was lower than 0.6 dB. The results show that our fabricated Si-based ARROW PCWs with 60° bends and Y-branch structures can provide good light transmission and power-splitting ability. PMID:22907016

  4. From the Dynamics of Coupled Map Lattices to the Psychological Arrow of Time

    NASA Astrophysics Data System (ADS)

    Atmanspacher, Harald; Filk, Thomas; Scheingraber, Herbert

    2006-10-01

    Stable neuronal assemblies are generally regarded as neural correlates of mental representations. Their temporal sequence corresponds to the experience of a direction of time, sometimes called the psychological time arrow. We show that the stability of particular, biophysically motivated models of neuronal assemblies, called coupled map lattices, is supported by causal interactions among neurons and obstructed by non-causal or anti-causal interactions among neurons. This surprising relation between causality and stability suggests that those neuronal assemblies that are stable due to causal neuronal interactions, and thus correlated with mental representations, generate a psychological time arrow. Yet this impact of causal interactions among neurons on the directed sequence of mental representations does not rule out the possibility of mentally less efficacious non-causal or anti-causal interactions among neurons.

  5. The Significance of Causally Coupled, Stable Neuronal Assemblies for the Psychological Time Arrow

    NASA Astrophysics Data System (ADS)

    Atmanspacher, Harald; Filk, Thomas; Scheingraber, Herbert

    2005-10-01

    Stable neuronal assemblies are generally regarded as neural correlates of mental representations. Their temporal sequence corresponds to the experience of a direction of time, sometimes called the psychological time arrow. We show that the stability of particular, biophysically motivated models of neuronal assemblies, called coupled map lattices, is supported by causal interactions among neurons and obstructed by non-causal or anti-causal interactions among neurons. This surprising relation between causality and stability suggests that those neuronal assemblies that are stable due to causal neuronal interactions, and thus correlated with mental representations, generate a psychological time arrow. Yet this impact of causal interactions among neurons on the directed sequence of mental representations does not rule out the possibility of mentally less efficacious non-causal or anti-causal interactions among neurons.

  6. Review of Cranked-Arrow Wing Aerodynamics Project: Its International Aeronautical Community Role

    NASA Technical Reports Server (NTRS)

    Lamar, John E.; Obara, Clifford J.

    2007-01-01

    This paper provides a brief history of the F-16XL-1 aircraft, its role in the High Speed Research (HSR) program and how it was morphed into the Cranked Arrow Wing Aerodynamics Project (CAWAP). Various flight, wind-tunnel and Computational Fluid Dynamics (CFD) data sets were generated during the CAWAP. These unique and open flight datasets for surface pressures, boundary-layer profiles and skinfriction distributions, along with surface flow data, are described and sample data comparisons given. This is followed by a description of how the project became internationalized to be known as Cranked Arrow Wing Aerodynamics Project International (CAWAPI) and is concluded by an introduction to the results of a 4 year CFD predictive study of data collected at flight conditions by participating researchers.

  7. Poor vigilance affects attentional orienting triggered by central uninformative gaze and arrow cues.

    PubMed

    Marotta, Andrea; Martella, Diana; Maccari, Lisa; Sebastiani, Mara; Casagrande, Maria

    2014-11-01

    Behaviour and neuroimaging studies have shown that poor vigilance (PV) due to sleep deprivation (SD) negatively affects exogenously cued selective attention. In the current study, we assessed the impact of PV due to both partial SD and night-time hours on reflexive attentional orienting triggered by central un-informative eye-gaze and arrow cues. Subjective mood and interference performance in emotional Stroop task were also investigated. Twenty healthy participants performed spatial cueing tasks using central directional arrow and eye-gaze as a cue to orient attention. The target was a word written in different coloured inks. The participant's task was to identify the colour of the ink while ignoring the semantic content of the word (with negative or neutral emotional valence). The experiment took place on 2 days. On the first day, each participant performed a 10-min training session of the spatial cueing task. On the second day, half of participants performed the task once at 4:30 p.m. (BSL) and once at 6:30 a.m. (PV), whereas the other half performed the task in the reversed order. Results showed that mean reaction times on the spatial cueing tasks were worsened by PV, although gaze paradigm was more resistant to this effect as compared to the arrow paradigm. Moreover, PV negatively affects attentional orienting triggered by both central un-informative gaze and arrow cues. Finally, prolonged wakefulness affects self-reported mood but does not influence interference control in emotional Stroop task. PMID:24718933

  8. Effects of vortex flaps on the low-speed aerodynamic characteristics of an arrow wing

    NASA Technical Reports Server (NTRS)

    Yip, L. P.; Murri, D. G.

    1981-01-01

    Tests were conducted in the Langley 12-foot low-speed wind-tunnel to determine the longitudinal and lateral-directional aerodynamic effects of plain and tabbed vortex flaps on a flat-plate, highly swept arrow-wing model. Flow-visualization studies were made using a helium-bubble technique. Static forces and moments were measured over an angle-of-attack range from 0 deg to 50deg for sideslip angles of 0 deg and + or - 4 deg.

  9. Attentional orienting induced by arrows and eye-gaze compared with an endogenous cue.

    PubMed

    Brignani, D; Guzzon, D; Marzi, C A; Miniussi, C

    2009-01-01

    Exogenous orienting has been widely studied by using peripheral cues whereas endogenous orienting has been studied with directional central cues. However, recent evidence has shown that centrally presented eye-gaze and arrows may produce an automatic rather than voluntary orienting of attention. Therefore, the aim of the present study was to investigate the behavioural and electrophysiological (event-related potentials-ERP) correlates of the attentional shift induced by arrows and eye-gaze. In order to have a control condition, we compared arrows and eye-gaze with a purely endogenous cue, i.e., a texture arbitrarily coding one direction. We analyzed the ERP components (P1, N1, P2a, P2p, P3) elicited by the cue stimuli and the early lateralised attentional effect (early directing attention negativity-EDAN). In addition, in order to investigate the topography of the neural mechanisms underlying the cortical activity in each cueing condition, we applied a temporal segmentation procedure. The results showed that the three cueing conditions induced a different strength of activation within the same cortical network. Occipito-parietal regions were involved in the early processing of visual information, followed by an involvement of frontal areas, likely implicated in learning associations. These data confirm the assumption that, in contrast to purely endogenous cues, arrows and eye-gaze induce a very fast attentional shift. However, the similarity of the ERP components and of the topographical cortical maps among conditions suggest that this early orienting of attention is more likely related to an overlearned association mechanism rather than to a real exogenous attentional process. PMID:18926835

  10. Evidence for K{sup +} {r_arrow} {pi}{sup +} {nu}{anti {nu}}

    SciTech Connect

    Kettell, S.; E787 Collaboration; E949 Collaboration

    1998-12-31

    The decay K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} has been observed for the first time. The E787 experiment has presented evidence for the K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} decay, based on the observation of a single clean event from data collected during the 1995 run of the AGS (Alternating Gradient Synchrotron at Brookhaven National Laboratory). The branching ratio indicated by this observation, B(K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}}) = 4.2{sub {minus}3.5}{sup +9.7} {times} 10{sup {minus}10}, is consistent with the Standard Model expectation although the central experimental value is four times larger. The final E787 data sample, from the 1995--99 runs, should reach a sensitivity of about eight times that of the 1995 run alone. A new experiment, E949, has been approved to run, starting in the year 2000, and is expected to achieve a sensitivity of more than an order of magnitude below the prediction of the Standard Model.

  11. Evidence for K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}

    SciTech Connect

    KETTELL,S.

    1998-12-18

    The first observation of the decay K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} has been reported. The E787 experiment presented evidence for the K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} decay, based on the observation of a single clean event from data collected during the 1995 run of the AGS (Alternating Gradient Synchrotron at Brookhaven National Laboratory). The branching ratio indicated by this observation, B(K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}) = 4.2{sub {minus}3.5}{sup +9.7} x 10{sup {minus}10}, is consistent with the Standard Model expectation although the central experimental value is four times larger. The final E787 data sample, from the 1995--98 runs, should reach a sensitivity of about five times that of the 1995 run alone. A new experiment, E949, has been given scientific approval and should start data collection in 2001. It is expected to achieve a sensitivity of more than an order of magnitude below the prediction of the Standard Model.

  12. Evidence for {Kappa}{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}}

    SciTech Connect

    Kettell, S.

    1998-12-31

    The first observation of the decay {Kappa}{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} has been reported. The E787 experiment presented evidence for the {Kappa}{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} decay, based on the observation of a single clean event from data collected during the 1995 run of the AGS (Alternating Gradient Synchrotron at Brookhaven National Laboratory). The branching ratio indicated by this observation, {Beta}({Kappa}{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}}) = 4.2{sub {minus}3.5}{sup +9.7} {times} 10{sup {minus}10}, is consistent with the Standard Model expectation although the central experimental value is four times larger. The final E787 data sample, from the 1995--98 runs, should reach a sensitivity of about five times that of the 1995 run alone. A new experiment, E949, has been given scientific approval and should start data collection in 2001. It is expected to achieve a sensitivity of more than an order of magnitude below the prediction of the Standard Model.

  13. Sociopolitical complexity and the bow and arrow in the American Southwest.

    PubMed

    VanPool, Todd L; O'Brien, Michael J

    2013-01-01

    The evolution of sociopolitical complexity, including heightened relations of cooperation and competition among large nonkin groups, has long been a central focus of anthropological research. Anthropologists suggest any number of variables that affect the waxing and waning of complexity and define the precise trajectories that groups take, including population density, subsistence strategies, warfare, the distribution of resources, and trade relationships. Changes in weaponry, here the introduction of the bow and arrow, can have profound implications for population aggregation and density, subsistence and settlement strategies, and access to resources, trade, and warfare.Bingham and Souza provide a general conceptual model for the relationship between complexity and the bow and arrow, arguing that this compound weapon system, whereby smaller projectiles travel at higher speed and are capable of hitting targets more accurately and at greater distances than hand-thrown darts, fundamentally favors the formation of larger groups because it allows for cost-effective means of dealing with conflicts of interest through social coercion, thereby dramatically transforming kin-based social relations. Here we consider the impacts the introduction of the bow and arrow had on sociopolitical complexity in the North American Southwest. PMID:23776047

  14. Expression of actin genes in the arrow worm Paraspadella gotoi (Chaetognatha).

    PubMed

    Yasuda, E; Goto, T; Makabe, K W; Satoh, N

    1997-12-01

    Arrow worms (the phylum Chaetognatha), one of the major marine planktonic animals, exhibit features characteristic to both deuterostomes and protostomes, and their ancestry therefore remains unknown. As the first step to elucidate the molecular bases of arrow worm phylogeny, physiology and embryology, we isolated cDNA clones for three different actin genes (PgAct1, PgAct2 and PgAct3) from the benthic species Paraspadella gotoi, and examined their expression patterns in adults and juveniles. The amino acid sequences of the three actins resembled each other, with identities ranging from 86% to 92%. However, the patterns of the spatial expression of the genes were independent. The PgAct1 gene might encode a cytoplasmic actin and was expressed in oogenic cells, spermatogenic cells, and cells in the ventral ganglion. The PgAct2 and PgAct3 genes encoded actins of divergent types. The former was expressed in well-developed muscle of the head (gnathic) region and trunk muscle cells, whereas the latter was expressed in muscle of the trunk and tail regions and oogenic cells. These results suggest that, similarly to other metazoans, the chaetognath contains multiple forms of actins, which are expressed in various manners in the adult and juvenile arrow worm. PMID:9520638

  15. Biostratigraphy and paleoenvironment of Morrowan (Zone 2) brachiopoda, Bird Spring Group, Arrow Canyon, Clark County, Nevada

    SciTech Connect

    Vaiden, R.C.; Langenheim, R.L.

    1985-02-01

    Comprehensive study of the Morrowan brachiopod faunas of the Bird Spring Group at Arrow Canyon, Clark County, Nevada, is important because the section has been suggested as a stratotype for the base and top of the Pennsylvanian Subsystem and for the Atoka Series. Twenty-three species of brachiopods belonging to 17 genera occur in zone 20 at Arrow Canyon. Many of these also occur in described Morrowan faunas in Wyoming, Colorado, Utah, and New Mexico; but similarities with the Mid-Continent and Appalachian assemblages are less. However, no striking regional differences are evident, and it appears that the North American Morrowan fauna is more or less homogeneous. In contrast to the exotic South American and Arctic elements known from Atokan, Missourian, and Virgilian rocks at Arrow Canyon, no foreign taxa have been noted in zone 20. Microfacies and faunal association indicate four distinct brachiopod-bearing environments; (1) relatively deep water below turbulence with few brachiopods on a soft substrate; (2) somewhat shallower, more turbulent water with many species, of which only a few are represented by large populations, living on a more firm substrate; (3) environments just below the zone of turbulence in which many species of brachiopods are represented by substantial populations on a calcarenitic substrate; and (4) crinoidal bars in the zone of turbulence with a few species represented by relatively few individuals.

  16. CP violation in the exclusive decays B{r_arrow}{pi}e{sup +}e{sup {minus}} and B{r_arrow}{rho}e{sup +}e{sup {minus}}

    SciTech Connect

    Krueger, F.; Sehgal, L.M.

    1997-11-01

    As a sequel to the calculation of the CP-violating asymmetry in the decay rates of b{r_arrow}dl{sup +}l{sup {minus}} and {bar b}{r_arrow}{bar d}l{sup +}l{sup {minus}}, we address in this paper the asymmetry in exclusive channels {bar B}{r_arrow}{pi}e{sup +}e{sup {minus}} and {bar B}{r_arrow}{rho}e{sup +}e{sup {minus}}, using form factors from two different models. In the invariant mass region 1GeV{lt}{radical} (s) {lt}M{sub J/{psi}}, the partial width asymmetry in the channel {bar B}{r_arrow}{pi} is {minus}6{percent} ({minus}2{percent}), and that in the channel {bar B}{r_arrow}{rho}, for one choice of form factors, is {minus}5{percent} ({minus}2{percent}), assuming Cabibbo-Kobayashi-Maskawa parameters {eta}=0.34, {rho}=0.3 ({minus}0.3). We also calculate the forward-backward asymmetry A{sub FB} of the e{sup {minus}} in the e{sup +}e{sup {minus}} center-of-mass system, and find average values {l_angle}A{sub FB}{r_angle}{sub {bar B}{r_arrow}{pi}}{equivalent_to}0, {l_angle}A{sub FB}{r_angle}{sub {bar B}{r_arrow}{rho}}={minus}17{percent}, to be compared with the inclusive result {l_angle}A{sub FB}{r_angle}{sub b{r_arrow}d}={minus}9{percent}. There is a CP-violating difference between A{sub FB} and the corresponding asymmetry in the antiparticle channel {bar A}{sub FB}. Formulas are given that are applicable to any flavor-changing neutral current channel {bar B}{r_arrow}P{sub q}(V{sub q})l{sup +}l{sup {minus}}, q=s,d, with m{sub l}{ne}0, including lepton spin effects. An approximate procedure is used to incorporate the {rho}, {omega}, and J/{psi} resonances. {copyright} {ital 1997} {ital The American Physical Society}

  17. Form factors of the transitions {gamma}{sup *}{pi}{sup 0} {r_arrow} {gamma} and {gamma}{sup *}{eta}{r_arrow}{gamma}

    SciTech Connect

    Afanasev, A.

    1994-04-01

    The author discusses possibilities to study {gamma}*{pi}{sup 0} and {gamma}*{eta} {r_arrow} {gamma} transition form factors at CEBAF energies. The author shows that for 4 GeV electron beam, these form factors can be measured at CEBAF for the 4-momentum transfers Q{sup 2} {le} 2.5 (GeV/c){sup 2} using virtual Compton scattering on the proton and nuclear target in the kinematic regime of low momentum transfers to the target. These measurements can be extended to Q{sup 2} {le} 4.0 (GeV/c){sup 2} using the electron beam with the energy 6 GeV.

  18. Complete leading order analysis in Chiral Perturbation Theory of the decays K{sub L}{r_arrow}{gamma}{gamma} and K{sub L}{r_arrow}l{sub +}l{sub {minus}}{gamma}

    SciTech Connect

    J. L. Goity; Longzhe Zhang

    1997-02-01

    The decays K{sub L}{r_arrow}{gamma}{gamma} and K{sub L}{r_arrow}l{sup +}l{sup {minus}}{gamma} are studied at the leading order p{sup 6} in Chiral Perturbation Theory. One-loop contributions stemming from the odd intrinsic parity {vert_bar}{Delta}S{vert_bar}=1 effective Lagrangian of order p{sup 4} are included and shown to be of possible relevance. They affect the decay K{sub L}{r_arrow}{gamma}{gamma} adding to the usual pole terms a piece free of counterterm uncertainties. In the case of the K{sub L}{r_arrow}l{sup +}l{sup {minus}}{gamma} decays the dependence of the form factor on the dilepton invariant mass requires a counterterm. The form factor may receive a sizeable contribution from chiral logarithms. Including considerations from the K{sub L}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{gamma} direct emission amplitude, the authors obtain two consistent scenarios. In one scenario the long distance contributions from the one-loop terms are important, while in the other they are marginal. In both cases the counterterm is shown to be significant.

  19. A 170 J electron beam pumped XeF(C{r_arrow}A) laser

    SciTech Connect

    Litzenberger, L.N.; Smith, M.J.

    1995-03-01

    A pulse output energy of 170 J has been achieved from an XeF (C{r_arrow}A) laser system, pumped by a pair of counterpropagating, three-meter-long electron beams. This represents a record for all types of pumping, for this excimer system. Energy was extracted from a volume of {approximately}100 L, using a free-running stable oscillator. No evidence of laser oscillations on the competing XeF(B{r_arrow}X) transition was observed. Within the extraction volume the laser gas was pumped at a rate of 140 kW/cm{sup 3} (time average value), for a period of 1.7 {mu}s. The optical cavity was folded, giving a gain length of 6 m. The optical pulse duration was 0.8 {mu}s (full width at half maximum), and the observed flux buildup time of {approximately}1 {mu}s was consistent with modeling and a measurement of the net gain. The specific output energy was 1.7 J/L which is comparable to that achieved in previous, small scale experiments at somewhat higher pump rate. The results confirm the volumetric scalability of the electron beam pumped XeF(C{r_arrow}A) laser system to high output energy per pulse, and the feasibility of operating this system at a low electron beam pump rate which relaxes constraints on the design of the electron gun and pulse power subsystems in a high output energy device. Means for extending the laser pulse duration and increasing the output energy of the specific test device are discussed. An output energy of {approximately}1,000 J is projected for an optimized gas cell width, for full size resonator mirrors, and with injection.

  20. Supersonic pressure measurements and comparison of theory to experiment for an arrow-wing configuration

    NASA Technical Reports Server (NTRS)

    Manro, M. E.

    1976-01-01

    A wind tunnel test of an arrow-wing-body configuration consisting of flat and twisted wings, as well as leading- and trailing-edge control surface deflections, was conducted at Mach numbers from 1.54 to 2.50 to provide an experimental pressure data base for comparison with theoretical methods. Theory-to-experiment comparisons of detailed pressure distributions were made using a state-of-the-art inviscid flow, constant-pressure-panel method. Emphasis was on conditions under which this theory is valid for both flat and twisted wings.

  1. Irreversibility and the Arrow of Time in a Quenched Quantum System.

    PubMed

    Batalhão, T B; Souza, A M; Sarthour, R S; Oliveira, I S; Paternostro, M; Lutz, E; Serra, R M

    2015-11-01

    Irreversibility is one of the most intriguing concepts in physics. While microscopic physical laws are perfectly reversible, macroscopic average behavior has a preferred direction of time. According to the second law of thermodynamics, this arrow of time is associated with a positive mean entropy production. Using a nuclear magnetic resonance setup, we measure the nonequilibrium entropy produced in an isolated spin-1/2 system following fast quenches of an external magnetic field. We experimentally demonstrate that it is equal to the entropic distance, expressed by the Kullback-Leibler divergence, between a microscopic process and its time reversal. Our result addresses the concept of irreversibility from a microscopic quantum standpoint. PMID:26588367

  2. Arrow-wing supersonic cruise aircraft structural design concepts evaluation. Volume 1: Sections 1 through 6

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1975-01-01

    The structural approach best suited for the design of a Mach 2.7 arrow-wing supersonic cruise aircraft was investigated. Results, procedures, and principal justification of results are presented. Detailed substantiation data are given. In general, each major analysis is presented sequentially in separate sections to provide continuity in the flow of the design concepts analysis effort. In addition to the design concepts evaluation and the detailed engineering design analyses, supporting tasks encompassing: (1) the controls system development; (2) the propulsion-airframe integration study; and (3) the advanced technology assessment are presented.

  3. Advanced structures technology applied to a supersonic cruise arrow-wing configuration

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1976-01-01

    The application of advanced technology to a promising aerodynamic configuration was explored to investigate the improved payload range characteristics over the configuration postulated during the National SST Program. The results of an analytical study performed to determine the best structural approach for design of a Mach number 2.7 arrow-wing supersonic cruise aircraft are highlighted. The data conducted under the auspices of the Structures Directorate of the National Aeronautics and Space Administration, Langley Research Center, established firm technical bases from which further trend studies were conducted to quantitatively assess the benefits and feasibility of using advanced structures technology to arrive at a viable advanced supersonic cruise aircraft.

  4. Analysis of trace elements in the giant panda and arrow bamboo

    NASA Astrophysics Data System (ADS)

    Wang, Nengming; Chen, Suqing; Chen, Jianxuan; Zhang, Dazhong; Feng, Wenhe

    1987-04-01

    Trace elements from the giant panda including hair, liver, kidney, ovary and testis, were determined by PIXE. Comparative studies of the elemental contents in hair, liver and kidney from epileptic and normal giant pandas were performed respectively. The differences in the elemental contents of leaf, stalk, and bamboo shoots from normal and withered arrows were determined. For this research work a Van de Graaff electrostatic accelerator and a Si(Li) semiconductor spectrometer at the Institute of Nuclear Science and Technology of Sichuan University were employed.

  5. Target asymmetry measurements of {gamma} p{r_arrow}{pi} {sup +}n with Phoenics at ELSA

    SciTech Connect

    Althoff, K.; Anton, G.; Arends, J.; Beulertz, W.; Bock, A.; Breuer, M.; Detemple, P.; Dutz, H.; Gehring, R.; Gemander, M.; Goertz, S.; Helbing, K.; Hey, J.; Kraemer, D.; Meyer, W.; Noeldeke, G.; Reicherz, G.; Thomas, A.; Zucht, B.

    1995-05-10

    The target asymmetry T of the reaction {gamma} p{r_arrow}{pi} {sup +}n has been measured with the Phoenics detector in combination with the Bonn frozen spin target at ELSA. For the first time the polarization observable T has been determined simultaneously over a large photon energy range (E{sub {gamma}}=220--800 MeV) and pion angles ({Theta}{sub {pi}}{sup m}=35{degree}--135{degree}) with a tagged photon facility. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  6. Arrow-wing supersonic cruise aircraft structural design concepts evaluation. Volume 4: Sections 15 through 21

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1975-01-01

    The analyses performed to provide structural mass estimates for the arrow wing supersonic cruise aircraft are presented. To realize the full potential for structural mass reduction, a spectrum of approaches for the wing and fuselage primary structure design were investigated. The objective was: (1) to assess the relative merits of various structural arrangements, concepts, and materials; (2) to select the structural approach best suited for the Mach 2.7 environment; and (3) to provide construction details and structural mass estimates based on in-depth structural design studies. Production costs, propulsion-airframe integration, and advanced technology assessment are included.

  7. Irreversibility and the Arrow of Time in a Quenched Quantum System

    NASA Astrophysics Data System (ADS)

    Batalhão, T. B.; Souza, A. M.; Sarthour, R. S.; Oliveira, I. S.; Paternostro, M.; Lutz, E.; Serra, R. M.

    2015-11-01

    Irreversibility is one of the most intriguing concepts in physics. While microscopic physical laws are perfectly reversible, macroscopic average behavior has a preferred direction of time. According to the second law of thermodynamics, this arrow of time is associated with a positive mean entropy production. Using a nuclear magnetic resonance setup, we measure the nonequilibrium entropy produced in an isolated spin-1 /2 system following fast quenches of an external magnetic field. We experimentally demonstrate that it is equal to the entropic distance, expressed by the Kullback-Leibler divergence, between a microscopic process and its time reversal. Our result addresses the concept of irreversibility from a microscopic quantum standpoint.

  8. Search for the Rare Decay barB^0 arrow D^*0γ

    NASA Astrophysics Data System (ADS)

    Bauer, Johannes

    2003-04-01

    We report on the search for the rare decay barB^0 arrow D^*0γ, which is dominated by a W-exchange and has not yet been observed. This analysis is based on a data sample comprised of 88.9× 10^6 B\\overline B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. ^* Work supported by U.S. Dept. of Energy grant DE-FG05-91ER40622.

  9. Arrow-wing supersonic cruise aircraft structural design concepts evaluation. Volume 3: Sections 12 through 14

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1975-01-01

    The design of an economically viable supersonic cruise aircraft requires the lowest attainable structural-mass fraction commensurate with the selected near-term structural material technology. To achieve this goal of minimum structural-mass fraction, various combinations of promising wing and fuselage primary structure were analyzed for the load-temperature environment applicable to the arrow wing configuration. This analysis was conducted in accordance with the design criteria specified and included extensive use of computer-aided analytical methods to screen the candidate concepts and select the most promising concepts for the in-depth structural analysis.

  10. Transonic pressure measurements and comparison of theory to experiment for three arrow-wing configurations

    NASA Technical Reports Server (NTRS)

    Manro, M. E.

    1982-01-01

    Wind tunnel tests of arrow-wing body configurations consisting of flat, twisted, and cambered twisted wings, as well as a variety of leading and trailing edge control surface deflections, were conducted at Mach numbers from 0.4 to 1.05 to provide an experimental pressure data base for comparison with theoretical methods. Theory to experiment comparisons of detailed pressure distributions were made using state of the art attached flow methods. Conditions under which these theories are valid for these wings are presented.

  11. Spatially resolved X-ray diffraction phase mapping and {alpha} {r_arrow} {beta} {r_arrow} {alpha} transformation kinetics in the heat-affected zone of commercially pure titanium arc welds

    SciTech Connect

    Elmer, J.W.; Wong, J.; Ressler, T.

    1998-11-01

    Spatially resolved X-ray diffraction (SRXRD) is used to map the {alpha} {r_arrow} {beta} {r_arrow} {alpha} phase transformation in the heat-affected zone (HAZ) of commercially pure titanium gas tungsten arc welds. In situ SRXRD experiments were conducted using a 180-{micro}m-diameter X-ray beam at the Stanford Synchrotron Radiation Laboratory (SSRL) (Stanford, CA) to probe the phases present in the HAZ of a 1.9 kW weld moving at 1.1 mm/s. Results of sequential linear X-ray diffraction scans made perpendicular to the weld direction were combined to construct a phase transformation map around the liquid weld pool. This map identifies six HAZ microstructural regions between the liquid weld pool and the base metal: (1) {alpha}-Ti that is undergoing annealing and recrystallization; (2) completely recrystallized {alpha}-Ti; (3) partially transformed {alpha}-Ti, where {alpha}-Ti and {beta}-Ti coexist; (4) single-phase {beta}-Ti; (5) back-transformed {alpha}Ti; and (6) recrystallized {alpha}-Ti plus back-transformed {alpha}-Ti. Although the microstructure consisted predominantly of {alpha}-Ti, both prior to and after the weld, the crystallographically textured starting material was altered during welding to produce different {alpha}-Ti textures within the resulting HAZ. Based on the travel speed of the weld, the {alpha} {r_arrow} {beta} transformation was measured to take 1.83 seconds during heat, while the {beta} {r_arrow} {alpha} transformation was measured to take 0.91 seconds during cooling. The {alpha} {r_arrow} {beta} transformation was characterized to be dominated by long-range diffusion growth on the leading (heating) side of the weld, while the {beta} {r_arrow} {alpha} transformation was characterized to be predominantly massive on the trailing (cooling) side of the weld, with a massive growth rate on the order of 100 {micro}m/s.

  12. A Comparison Study of the Exclusive Decays barB^0 arrow D^*+ l^- barνl and B^- arrow D^*0 l^- barνl Using Partial Reconstruction.

    NASA Astrophysics Data System (ADS)

    Godang, Romulus; Kinoshita, Kay

    2000-04-01

    Using 2.81 fb-1 of Υ(4S) data collected with the CLEO II detector at the Cornell Electron Storage Ring, we compare the exclusive decays barB^0 arrow D^*+ l^- barνl and B^- arrow D^*0 l^- barν_l. We use a partial reconstruction method, where only a lepton and soft pion are detected and the D is not reconstructed. The method yields sufficient statistics to allow a reasonable comparison as a function of pion momentum. A preliminary result of the charged to neutral B production ratio at the Υ(4S) will be presented.

  13. Mid-term clinical results of medial meniscus repair with the meniscus arrow in the unstable knee.

    PubMed

    Koukoulias, Nikolaos; Papastergiou, Stergios; Kazakos, Konstantinos; Poulios, Georgios; Parisis, Konstantinos

    2007-02-01

    The medial meniscus is a secondary stabilizer to anterior tibial translation and provides significant stability, especially in an ACL-deficient knee. The purpose of this study is to evaluate the clinical outcome of medial meniscus repair in the unstable knee. Between 1997 and 2002, 11 patients, with a mean age of 25.8 years (range 15-39 years), underwent all-inside medial meniscus repair, using the Meniscus Arrow, for unstable medial meniscus tear in ACL-deficient knees. For various reasons none of these patients underwent ACL reconstruction. The average follow-up was 73 months (range 52-91 months). There were three failures (27.3%) defined as the need for reoperation and partial meniscectomy. The mean Tegner activity score decreased from 6.75 (pretrauma) to 4.5 (postoperatively). The average Lysholm and subjective IKDC scores were 83 and 77.4, respectively. Two patients were graded as B (nearly normal) and six as C (abnormal), according to the IKDC knee evaluation form. KT-2000 arthrometry demonstrated that sagittal knee laxity was more than 5 mm in all knees (side to side difference). MRI demonstrated grade three signal alterations at the repair site of meniscus in three patients and signs of cartilage damage in two patients. All patients were asymptomatic during daily activities but seven out of eight reported pain or effusion after sports. Medial meniscus repair in the ACL-deficient knee is not contraindicated. The need of reducing the level of physical activity is essential. PMID:16967201

  14. Determination of the {ital b}{r_arrow}{ital c} handedness using nonleptonic {Lambda}{sub {ital c}} decays

    SciTech Connect

    Koenig, B.; Koerner, J.G.; Kraemer, M.

    1994-03-01

    We consider possibilities to determine the handedness of {ital b}{r_arrow}{ital c} current transitions using semileptonic baryonic {Lambda}{sub {ital b}}{r_arrow}{Lambda}{sub {ital c}} transitions. We propose to analyze the longitudinal polarization of the daughter baryon {Lambda}{sub {ital c}} by using momentum-spin correlation measurements in the form of forward-backward (FB) asymmetry measures involving its nonleptonic decay products. We use an explicit form factor model to determine the longitudinal polarization of {Lambda}{sub {ital c}} in the semileptonic decay {Lambda}{sub {ital b}}{r_arrow}{Lambda}{sub {ital c}}+{ital l}{sup {minus}}+{bar {nu}}{sub {ital l}}. The mean longitudinal polarization of {Lambda}{sub {ital c}} is negative (positive) for left-chiral (right-chiral) {ital b}{r_arrow}{ital c} current transitions. The frame-dependent longitudinal polarization of {Lambda}{sub {ital c}} is large ({congruent}80%) in the {Lambda}{sub {ital b}} rest frame and somewhat smaller (30%--40%) in the lab frame when the {Lambda}{sub {ital b}}`s are produced on the {ital Z}{sup 0} peak. We suggest to use nonleptonic decay modes of {Lambda}{sub {ital c}} to analyze its polarization and thereby to determine the chirality of the {ital b}{r_arrow}{ital c} transition. Since {Lambda}{sub {ital b}}`s produced on the {ital Z}{sup 0} are expected to be polarized we discuss issues of the polarization transfer in {Lambda}{sub {ital b}}{r_arrow}{Lambda}{sub {ital c}} transitions. We also investigate the {ital p}{sub {perpendicular}}- and {ital p}-cut sensitivity of our predictions for the polarization of {Lambda}{sub {ital c}}.

  15. Bose-Einstein correlations in e{sup +}e{sup {minus}} {r_arrow} W{sup +}W{sup {minus}} at a linear collider

    SciTech Connect

    Chekanov, S. V.; De Roeck, A.; De Wolf, E. A.

    2000-03-03

    The authors show that the most popular method to simulate Bose-Einstein (BE) interference effects predicts negligible correlations between identical pions originating from the hadronic decay of different W's produced in e{sup +}e{sup {minus}} {r_arrow} W{sup +}W{sup {minus}} {r_arrow} 4 jets at typical linear collider energies.

  16. Detailed study of the T = 0, NN interaction via N-italic-arrow-rightP- scattering at 68 MEV

    SciTech Connect

    Henneck, R.; Campbell, J.; Gysin, C.; Hammans, M.; Lorenzon, W.; Pickar, M.A.; Sick, I.; Konter, J.A.; Mango, S.; Van den Brandt, B.; and others

    1988-11-20

    We report on first results for a measurement of the spin correlation parameter A/sub z//sub z/ in n-italic-arrow-rightp-arrow-right scattering at 68 MeV, which is highly sensitive to the mixing parameter epsilon/sub 1/. A phase shift analysis of these data, together with forthcoming results of our measurements of /sup d//sup sigma//sub d//sub ..cap omega../ and A/sub y/ at the same energy is expected to allow a determination of epsilon/sub 1/ to within /similar to/ +- 0.3/sup 0/.

  17. Integration and characterization of SiN nanopores for single-molecule detection in liquid-core ARROW waveguides

    NASA Astrophysics Data System (ADS)

    Rudenko, M. I.; Yin, D.; Holmes, M.; Hawkins, A. R.; Schmidt, H.

    2007-02-01

    We demonstrate a method for integrating silicon nitride nanopores in liquid core Anti Resonant Reflecting Optical Waveguides (ARROW) for single molecule electrical detection and control. We use a two-step integration process when a micropore is fabricated first, paving the way for subsequent nanopore integration in the first silicon nitride layer of the ARROW structure. Nanopores with dimensions as small as 11 nm were fabricated using a Focused Ion Beam shrinking process commensurate with single particle gating of viruses, proteins, ribosomes and other biomolecules.

  18. The Pitch Imagery Arrow Task: Effects of Musical Training, Vividness, and Mental Control

    PubMed Central

    Gelding, Rebecca W.; Thompson, William Forde; Johnson, Blake W.

    2015-01-01

    Musical imagery is a relatively unexplored area, partly because of deficiencies in existing experimental paradigms, which are often difficult, unreliable, or do not provide objective measures of performance. Here we describe a novel protocol, the Pitch Imagery Arrow Task (PIAT), which induces and trains pitch imagery in both musicians and non-musicians. Given a tonal context and an initial pitch sequence, arrows are displayed to elicit a scale-step sequence of imagined pitches, and participants indicate whether the final imagined tone matches an audible probe. It is a staircase design that accommodates individual differences in musical experience and imagery ability. This new protocol was used to investigate the roles that musical expertise, self-reported auditory vividness and mental control play in imagery performance. Performance on the task was significantly better for participants who employed a musical imagery strategy compared to participants who used an alternative cognitive strategy and positively correlated with scores on the Control subscale from the Bucknell Auditory Imagery Scale (BAIS). Multiple regression analysis revealed that Imagery performance accuracy was best predicted by a combination of strategy use and scores on the Vividness subscale of BAIS. These results confirm that competent performance on the PIAT requires active musical imagery and is very difficult to achieve using alternative cognitive strategies. Auditory vividness and mental control were more important than musical experience in the ability to perform manipulation of pitch imagery. PMID:25807078

  19. Radiative Recombination in the Terrestrial Nightglow: e + O^+ arrow O + hν

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.; Cosby, P. C.; Sharpee, B. D.; Huestis, D. L.

    2003-10-01

    Large aperture telescopes have been equipped with superbly calibrated high-resolution spectrographs with performance comparable with the best laboratory instrumentation. From analysis of spectra of the ``empty sky" (really the Earth's atmosphere) we have made the first experimental determination of the relative strengths of 25 emission lines between 390 and 930 nm from Rydberg excited states following the reaction e + O^+ arrow O + hν in the terrestrial ionosphere. We observe ns,np,nd arrow 3s,3p orbital transitions, around the O^+(^4S) core, for n=3-11 and for triplet and quintet overall spin. Two modern calculations of cross sections for radiative recombination are in use by atmospheric scientists [1] and astronomers [2]. In general, the observed relative intensities agree rather well with theory, especially for the quintet states. Modeling the triplets is complicated by optical trapping. Supported by the NSF and NASA. [1] V. Escalante and G. A. Victor, Planet. Space Sci. 40, 1705 (1992). [2] D. Pequignot, P. Petitjean, and C. Boisson, Astron. Astrophys. 251, 680 (1991).

  20. The Pitch Imagery Arrow Task: effects of musical training, vividness, and mental control.

    PubMed

    Gelding, Rebecca W; Thompson, William Forde; Johnson, Blake W

    2015-01-01

    Musical imagery is a relatively unexplored area, partly because of deficiencies in existing experimental paradigms, which are often difficult, unreliable, or do not provide objective measures of performance. Here we describe a novel protocol, the Pitch Imagery Arrow Task (PIAT), which induces and trains pitch imagery in both musicians and non-musicians. Given a tonal context and an initial pitch sequence, arrows are displayed to elicit a scale-step sequence of imagined pitches, and participants indicate whether the final imagined tone matches an audible probe. It is a staircase design that accommodates individual differences in musical experience and imagery ability. This new protocol was used to investigate the roles that musical expertise, self-reported auditory vividness and mental control play in imagery performance. Performance on the task was significantly better for participants who employed a musical imagery strategy compared to participants who used an alternative cognitive strategy and positively correlated with scores on the Control subscale from the Bucknell Auditory Imagery Scale (BAIS). Multiple regression analysis revealed that Imagery performance accuracy was best predicted by a combination of strategy use and scores on the Vividness subscale of BAIS. These results confirm that competent performance on the PIAT requires active musical imagery and is very difficult to achieve using alternative cognitive strategies. Auditory vividness and mental control were more important than musical experience in the ability to perform manipulation of pitch imagery. PMID:25807078

  1. Bioaccumulation and food-chain analysis for evaluating ecological risks in terrestrial and wetland habitats: Availability-transfer factors (ATFs) in soil {r_arrow} soil macroinvertebrate {r_arrow} amphibian food chains

    SciTech Connect

    Linder, G.; Bollman, M.; Callahan, C.; Gillette, C.; Nebeker, A.; Wilborn, D.

    1998-12-31

    As part of the ecological risk assessment process for terrestrial and wetland habitats, the evaluation of bioaccumulative chemicals of concern (BCCs) is frequently pursued through food-chain analysis with a subsequent comparison of daily doses to benchmark toxicity reference values, when available. Food-chain analysis has frequently been applied to the analysis of exposure to BCCs identified as chemicals of potential ecological concern (COPECs) in the ecological risk assessment process. Here, designed studies focused on wetland food-chains such as hydric soil {r_arrow} soil macroinvertebrate {r_arrow} amphibian and terrestrial food-chains such as soil {r_arrow} plant {r_arrow} small mammal illustrate an approach for the derivation and validation of trophic transfer factors for metals considered as COPECs such as cadmium, chromium, copper, lead, and zinc. The results clearly indicate that the transfer of chemicals between trophic levels is critical in the bioaccumulation process in wetland and terrestrial food-chains and is influenced by numerous interacting abiotic and biotic factors, including physicochemical properties of soil, and the role, if any, that the metal has in the receptor as a required trace element.

  2. New result on K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} from BNL E787

    SciTech Connect

    REDLINGER,G.

    1999-06-21

    E787 at BNL has reported evidence for the rare decay K{sup +} {r_arrow} {pi}{sup +}{nu}{bar {nu}}, based on the observation of one candidate event. In this paper, we present the result of analyzing a new dataset of comparable sensitivity to the published result.

  3. Comparison of gunshot wounds and field-tipped arrow wounds using morphological criteria and chemical spot tests.

    PubMed

    Randall, B; Newby, P

    1989-05-01

    Arrow wounds represent an unusual class of wounds rarely seen by most death investigators. Although the edged, broadhead-tipped arrow produces a wound usually characteristic of archery/crossbow weapons, the plain, field-tipped arrow wound can be confused with gunshot injuries in those cases in which powder residue or firearm projectiles or fragments or both are not recovered. We present a case of a deer carcass with a wound of uncertain firearm or archery origin which initiated a comparison of firearm wounds and archery wounds on fresh road-killed deer. We found the following features to be valuable in the differentiation of gunshot wounds and field-tipped archery wounds: First, the majority of the gunshot wounds (but none of the arrow wounds) had identifiable, macroscopic, wipe-off material and chemically identifiable wipe-off residue by spot test. Second, the archery wound defects had very inconspicuous abrasion rings as compared to the often prominent abrasion rings of gunshot wounds. Third, the actual central defect in the archery wounds was more likely to be oblong or slit-like compared to the gunshot wound defects, which were more likely to be round. PMID:2738561

  4. Clinical results of meniscus repair with the meniscus arrow: a 4- to 8-year follow-up study.

    PubMed

    Koukoulias, Nikolaos; Papastergiou, Stergios; Kazakos, Konstantinos; Poulios, Georgios; Parisis, Konstantinos

    2007-02-01

    The short-term clinical results of meniscus repair with the meniscus arrow were promising. Unfavorable outcomes were reported in two studies, with longer follow-up, raising concerns about the efficacy of this device. We retrospectively reviewed 62 patients (mean age 23.7 years; range 14-37 years) that underwent all-inside meniscus repair, using the meniscus arrow. Seventeen patients had an isolated meniscus tear (ACL intact group) and 45 patients concomitant ACL rupture that was reconstructed at the same time with the meniscus repair (ACL reconstructed group). All patients followed a non-aggressive rehabilitation protocol. Follow-up was assessed by clinical examination, Lysholm and Tegner score, IKDC knee examination form and KT-2000 arthrometry for the anteroposterior laxity of the reconstructed knees. At an average follow-up of 73 months (range 49-96 months) there were three failures (4.8%), one from the ACL intact group and two from the ACL reconstructed group. One patient developed arthrofibrosis (ACL reconstructed group) that resolved conservatively. Soft tissue irritation at the repair site was noted in three patients. In two patients the symptoms were transient. In the third patient the arrow tip was cut off under local anaesthesia due to saphenous infrapatellar branch irritation and the symptoms resolved (inappropriate arrow size). KT-2000 arthrometry showed that sagittal knee laxity was less than 3 mm in all reconstructed knees. The mean Tegner activity score decreased from 6.7 (pretrauma) to 6.2 (postoperatively). The average Lysholm score was 96, with normal or nearly normal function of all success knees, according to the IKDC knee examination form. Our results show a high clinical success rate of meniscus repair with the meniscus arrow. We found this device both safe and effective. PMID:16858563

  5. Scan path entropy and arrow plots: capturing scanning behavior of multiple observers.

    PubMed

    Hooge, Ignace; Camps, Guido

    2013-01-01

    Designers of visual communication material want their material to attract and retain attention. In marketing research, heat maps, dwell time, and time to AOI first hit are often used as evaluation parameters. Here we present two additional measures (1) "scan path entropy" to quantify gaze guidance and (2) the "arrow plot" to visualize the average scan path. Both are based on string representations of scan paths. The latter also incorporates transition matrices and time required for 50% of the observers to first hit AOIs (T50). The new measures were tested in an eye tracking study (48 observers, 39 advertisements). Scan path entropy is a sensible measure for gaze guidance and the new visualization method reveals aspects of the average scan path and gives a better indication in what order global scanning takes place. PMID:24399993

  6. Titanium and advanced composite structures for a supersonic cruise arrow wing configuration

    NASA Technical Reports Server (NTRS)

    Turner, M. J.; Hoy, J. M.

    1976-01-01

    Structural design studies were made, based on current technology and on an estimate of technology to be available in the mid 1980's, to assess the relative merits of structural concepts and materials for an advanced arrow wing configuration cruising at Mach 2.7. Preliminary studies were made to insure compliance of the configuration with general design criteria, integrate the propulsion system with the airframe, and define an efficient structural arrangement. Material and concept selection, detailed structural analysis, structural design and airplane mass analysis were completed based on current technology. Based on estimated future technology, structural sizing for strength and a preliminary assessment of the flutter of a strength designed composite structure were completed. An advanced computerized structural design system was used, in conjunction with a relatively complex finite element model, for detailed analysis and sizing of structural members.

  7. The f0 Mesons in Processes pi][pi [right arrow] [pi][pi], KK

    NASA Astrophysics Data System (ADS)

    Surovtsev, Yu. S.; Krupa, D.; Nagy, M.

    2002-06-01

    Combined analysis the experimental data on the processes pi][pi [right arrow] pi][pi, KK in the channel with IGJPC = 0+0++ in a model-independent approach leads to the following results: 1) The f0(665) state with properties of the sigma-meson is proved to exist; 2) It is shown that the f0(980) and especially f0(1370) (if exists) have a dominant ss component; 3) Indications for the glueball nature of the f0(1500) and for the considerable ss component in the f0(1710) are obtained; 4) Conclusion on the linear realization of chiral symmetry (chiS) is drawn.

  8. Scan path entropy and arrow plots: capturing scanning behavior of multiple observers

    PubMed Central

    Hooge, Ignace; Camps, Guido

    2013-01-01

    Designers of visual communication material want their material to attract and retain attention. In marketing research, heat maps, dwell time, and time to AOI first hit are often used as evaluation parameters. Here we present two additional measures (1) “scan path entropy” to quantify gaze guidance and (2) the “arrow plot” to visualize the average scan path. Both are based on string representations of scan paths. The latter also incorporates transition matrices and time required for 50% of the observers to first hit AOIs (T50). The new measures were tested in an eye tracking study (48 observers, 39 advertisements). Scan path entropy is a sensible measure for gaze guidance and the new visualization method reveals aspects of the average scan path and gives a better indication in what order global scanning takes place. PMID:24399993

  9. Effect of a simulated engine jet blowing above an arrow wing at Mach 2.0

    NASA Technical Reports Server (NTRS)

    Shrout, B. L.; Hayes, C.

    1977-01-01

    The effects of a gas jet simulating a turbojet engine exhaust blowing above a cambered and twisted arrow wing were investigated. Tests were conducted in the Langley 4-foot supersonic pressure tunnel at a Mach number of 2.0. Nozzle pressure ratios from 1 to 64 were tested with both helium and air used as jet gases. The tests were conducted at angles of attack from -2 deg to 8 deg at a Reynolds number of 9,840,000 per meter. Only the forces and moments on the wing were measured. Results of the investigation indicated that the jet blowing over the wing caused reductions in maximum lift-drag ratio of about 4 percent for helium and 6 percent for air at their respective design nozzle pressure ratios, relative to jet-off data. Moderate changes in the longitudinal, vertical, or angular positions of the jet relative to the wing had little effect on the wing aerodynamic characteristics.

  10. Study of advanced composite structural design concepts for an arrow wing supersonic cruise configuration

    NASA Technical Reports Server (NTRS)

    Turner, M. J.; Grande, D. L.

    1978-01-01

    Based on estimated graphite and boron fiber properties, allowable stresses and strains were established for advanced composite materials. Stiffened panel and conventional sandwich panel concepts were designed and analyzed, using graphite/polyimide and boron/polyimide materials. The conventional sandwich panel was elected as the structural concept for the modified wing structure. Upper and lower surface panels of the arrow wing structure were then redesigned, using high strength graphite/polyimide sandwich panels, retaining the titanium spars and ribs from the prior study. The ATLAS integrated analysis and design system was used for stress analysis and automated resizing of surface panels. Flutter analysis of the hybrid structure showed a significant decrease in flutter speed relative to the titanium wing design. The flutter speed was increased to that of the titanium design by selective increase in laminate thickness and by using graphite fibers with properties intermediate between high strength and high modulus values.

  11. Evaluation of structural design concepts for an arrow-wing supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1977-01-01

    An analytical study was performed to determine the best structural approach for design of primary wing and fuselage structure of a Mach 2.7 arrow wing supersonic cruise aircraft. Concepts were evaluated considering near term start of design. Emphasis was placed on the complex interactions between thermal stress, static aeroelasticity, flutter, fatigue and fail safe design, static and dynamic loads, and the effects of variations in structural arrangements, concepts and materials on these interactions. Results indicate that a hybrid wing structure incorporating low profile convex beaded and honeycomb sandwich surface panels of titanium alloy 6Al-4V were the most efficient. The substructure includes titanium alloy spar caps reinforced with boron polyimide composites. The fuselage shell consists of hat stiffened skin and frame construction of titanium alloy 6Al-4V. A summary of the study effort is presented, and a discussion of the overall logic, design philosophy and interaction between the analytical methods for supersonic cruise aircraft design are included.

  12. Low-speed wind tunnel investigation of an advanced supersonic cruise arrow-wing configuration

    NASA Technical Reports Server (NTRS)

    Coe, P. L., Jr.; Smith, P. M.; Parlett, L. P.

    1977-01-01

    A preliminary assessment of possible means for improving the low speed aerodynamic characteristics of advanced supersonic cruise arrow wing configurations and to extend the existing data base of such configurations has been made. Principle configuration variables included wing-leading and trailing-edge flap deflection, fuselage nose strakes, and engine exhaust nozzle deflection. Results showed that deflecting the wing leading edge apex flaps downward provided improved longitudinal stability but resulted in reduced directional stability. The model exhibited relatively low values of directional stability over the operational angle of attack range and experienced large asymmetric yawing moments at high angles of attack. The use of nose strakes was found to be effective in increasing the directional stability and eliminating the asymmetric yawing moment.

  13. Nonstandard. gamma. gamma. r arrow l sup + l minus processes in relativistic heavy-ion collisions

    SciTech Connect

    Almeida, L.D.; Natale, A.A.; Novaes, S.F. ); Eboli, O.J.P. )

    1991-07-01

    We study lepton pair production in heavy-ion collisions with emphasis on nonstandard contributions to the QED subprocess {gamma}{gamma}{r arrow}{ital l}{sup +}{ital l{minus}}. The existence of compositeness of fermions and/or bosons can be tested in this reaction up to the TeV mass scale. We show that for some processes the capabilities of relativistic heavy-ion colliders to disclose new physics surpass the possibilities of {ital e}{sup +}{ital e{minus}} or {ital p{bar p}} machines. In particular, spin-zero composite particles which couple predominantly to two photons, predicted in composite models, can be studied in a broad range of masses.

  14. The emergence of time's arrows and special science laws from physics

    PubMed Central

    Loewer, Barry

    2012-01-01

    In this paper, I will argue that there is an important connection between two questions concerning how certain features of the macro world emerge from the laws and processes of fundamental microphysics and suggest an approach to answering these questions. The approach involves a kind of emergence but quite different from ‘top-down’ emergence discussed at the conference, for which an earlier version of this paper was written. The two questions are (i) How do ‘the arrows of time’ emerge from microphysics? (ii) How do macroscopic special science laws and causation emerge from microphysics? Answering these questions is especially urgent for those, who like myself, think that a certain version of physicalism, which I call ‘micro-physical completeness’ (MC), is true. According to MC, there are fundamental dynamical laws that completely govern (deterministically or probabilistically), the evolution of all micro-physical events and there are no additional ontologically independent dynamical or causal special science laws. In other words, there is no ontologically independent ‘top-down’ causation. Of course, MC does not imply that physicists now or ever will know or propose the complete laws of physics. Or even if the complete laws were known we would know how special science properties and laws reduce to laws and properties of fundamental physics. Rather, MC is a contingent metaphysical claim about the laws of our world. After a discussion of the two questions, I will argue the key to showing how it is possible for the arrows of time and the special science laws to emerge from microphysics and a certain account of how thermodynamics is related to fundamental dynamical laws. PMID:23386956

  15. Time's Arrow and Archimedes' Point - New Directions for the Physics of Time

    NASA Astrophysics Data System (ADS)

    Price, Huw

    1997-12-01

    Why is the future so different from the past? Why does the past affect the future and not the other way around? What does quantum mechanics really tell us about the world? In this important and accessible book, Huw Price throws fascinating new light these great mysteries of modern physics, and connects them in a wholly original way. Price begins with the mystery of the arrow of time. Price shows that, for over a century, most physicists have thought about problems of time in the wrong way. Misled by the human perspective from within time, which distorts and exaggerates the differences between past and future, they have fallen victim to what Price calls the "double standard fallacy": proposed explanations of the difference between the past and the future turn out to rely on a difference which has been slipped in at the beginning, when the physicists themselves treat the past and future in different ways. To avoid this fallacy, Price argues, we need to overcome our natural tendency to think about the past and the future differently. We need to imagine a point outside time--an Archimedean "view from nowhen"--from which to observe time in an unbiased way. Time's Arrow and Archimedes'Point presents an innovative and controversial view of time and contemporary physics. In this exciting book, Price urges physicists, philosophers, and anyone who has ever pondered the mysteries of time to look at the world from the fresh perspective of Archimedes' Point and gain a deeper understanding of ourselves, the universe around us, and our own place in time.

  16. Measurement of Br({Kappa}{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}}): New results from BNL E791

    SciTech Connect

    Schwartz, A.

    1991-12-31

    Using a sample of 349 {Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}} candidates collected during the 1990 data run, the author measures a branching fraction Br({Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}}) = (6.96 {+-} 0.40 {+-} 0.22) {times} 10{sup {minus}9}. The sample used is the largest to date of {Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}} events. The result is close to the unitarity bound 6.83 {times} 10{sup {minus}9} coming from an absorptive 2-{gamma} intermediate state.

  17. Signal and backgrounds for the single production of scalar and vector leptoquarks at the CERN LHC

    SciTech Connect

    Cieza Montalvo, J.E.; Eboli, O.J.; Eboli, O.J.; Magro, M.B.; Mercadante, P.G.

    1998-11-01

    We perform a detailed analysis of the potentiality of the CERN Large Hadron Collider to study the single production of leptoquarks via pp{r_arrow}e{sup {plus_minus}}q{r_arrow} leptoquark {r_arrow}e{sup {plus_minus}}q, with e{sup {plus_minus}} generated by the splitting of photons radiated by the protons. Working with the most general SU(2){sub L}{circle_times}U(1){sub Y} invariant effective Lagrangian for scalar and vector leptoquarks, we analyze in detail the leptoquark signals and backgrounds that lead to a final state containing an e{sup {plus_minus}} and a hard jet with approximately balanced transverse momenta. Our results indicate that the LHC will be able to discover leptoquarks with masses up to 2{endash}3 TeV, depending on their type, for Yukawa couplings of the order of the electromagnetic one. {copyright} {ital 1998} {ital The American Physical Society}

  18. Chromosomal localization of the genes encoding the kinetochore proteins CENPE and DENPF to human chromosomes 4q24{r_arrow}q25 and 1q32{r_arrow}q41, respectively, by fluorescence in situ hybridization

    SciTech Connect

    Testa, J.R.; Zhou, J.Y.; Bell, D.W.; Yen, T.J.

    1994-10-01

    CENPE and CENPF are human kinetochore proteins of 312 and {approximately}400 kDa, respectively. As part of an effort to characterize the functions of these two proteins, we have used their respective cDNAs to map their human chromosomal locations by fluorescence in situ hybridization. The gene that encodes CENPE, a kinetochore-associated motor protein that is postulated to segregate chromosomes during mitosis, maps to chromosome 4q24{r_arrow}q25. The CENPF gene, which encodes a structural protein of the kinetochore, maps to chromosome 1q32{r_arrow}q41 within close proximity to the genetic locus that is linked to Van der Woude syndrome. 8 refs., 1 fig.

  19. Trisomy 1q42{r_arrow}qter in a sister and brother: Further delineation of the {open_quotes}trisomy 1q42{r_arrow}qter syndrome{close_quotes}

    SciTech Connect

    Verschuuren-Bemelmans, C.C.; Leegte, B.; Hodenius, T.M.J.

    1995-07-31

    We report on a 22-year-old woman and her 21-year-old brother with mild mental retardation, long face, prominent forehead, retrognathia, and (relative) macrocephaly. At birth they were small for date, their length is now below the 10th centile. Chromosome analysis demonstrated a nearly pure trisomy 1q42{r_arrow}qter in both patients due to unbalanced segregation of a paternal reciprocal balanced translocation 46,XY,t(1;15) (q42;p11). This is the second report of a nearly pure trisomy 1q42{r_arrow}qter. When comparing the manifestations of our patients with those of other reported cases we conclude that the most characteristic clinical manifestations of this syndrome are macrocephaly, prominent forehead, micro/retrognathia, large fontanelle, intrauterine growth retardation, postnatal growth retardation, and mental retardation. 56 refs., 4 figs., 1 tab.

  20. Prospects for measuring K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} and K{sub L}{sup 0} {r_arrow} {pi}{sup 0} {nu}{bar {nu}} at BNL

    SciTech Connect

    Bryman, D.A.; Littenberg, L.

    2000-09-18

    Rare kaon decay experiments underway or planned for the BNL AGS will yield new and independent determinations of V*{sub ts}V{sub td}. A measurement of B(K{sub L}{sup 0} {r_arrow} {pi}{sup 0} {nu}{bar {nu}}) allows a determination of the imaginary part of this quantity, which is the fundamental CP-violating parameter of the Standard Model, in a uniquely clean manner. Since the measurement of B(K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}) determines {vert_bar}V*{sub ts}V{sub td}, a complete derivation of the unitarity triangle is facilitated. These results can be compared to high precision data expected to come from the B sector in a number of ways, allowing for unique tests of new physics.

  1. Coherent diffraction reactions p + C {r_arrow} ({Epsilon}(1385){sup O}K{sup +}) + C and p + C {r_arrow} ({Epsilon}{sup O}K{sup +}) + C: The search for exotic baryons

    SciTech Connect

    Vavilov, D.V.; Viktorov, V.A.; Golovkin, S.V.

    1995-08-01

    The coherent diffractive reactions p + C {r_arrow} ({Epsilon}(1385){sup O}K{sup +}) + C and p + C {r_arrow} ({Epsilon}{sup O}K{sup +}) + C are investigated in experiments with the SPHINX detector irradiated by 70-GeV protons. A structure X(2050) with M = 2052 {plus_minus} 6 MeV and {Gamma} = 91 {plus_minus} 17MeV in the {Epsilon}{sup O}K{sup +} mass spectrum are observed in the former and latter processes, respectively. The small decay widths of these states and the anomalously large branching ratios of their decays that involve the emission of strange particles make them serious candidates for cryptoexotic varyons with hidden strangeness. 18 refs., 6 figs., 2 tabs.

  2. The mechanism of synthesis of a mixed-linkage (1{r{underscore}arrow}3), (1{r{underscore}arrow}4) {beta}-D-glucan in maize. Evidence for multiple sites of glucosyl transfer in the synthase complex

    SciTech Connect

    Buckeridge, M.S.; Vergara, C.E.; Carpita, N.C.

    1999-08-01

    The authors examined the mechanism of synthesis in vitro of (1{r{underscore}arrow}3), (1{r{underscore}arrow}4){Beta}-D-glucan ({Beta}-glucan), a growth-specific cell wall polysaccharide round in grasses and cereals. {beta}-Glucan is composed primarily of cellotriosyl and cellotetraosyl units linked by single (1{r{underscore}arrow}3){beta}-linkages. The ratio of cellotriosyl and cellotetraosyl units in the native polymer is strictly controlled at between 2 and 3 in all grasses, whereas the ratios of these units in {Beta}-glucan formed in vitro vary from 1.5 with 5 {micro}M UDP-glucose (GLc) to over 11 with 30 nM substrate. These results support a model in which three sites of glycosyl transfer occur within the synthase complex to produce the cellobiosyl-(1{r{underscore}arrow}3)-D-glucosyl units. The authors propose that failure to fill one of the sites results in the iterative addition of one or more cellobiosyl units to produce the longer cellodextrin units in the polymer. Variations in the UDP-Glc concentration in excised maize (Zea mays) coleoptiles did not result in wide variations in the ratios of cellotriosyl and cellotetraosyl units in {beta}-glucan synthesized in vivo, indicating that other factors control delivery of UDP-Glc to the synthase. In maize sucrose synthase is enriched in Golgi membranes and plasma membranes and may be involved in the control of substrate delivery to {beta}-glucan synthase and cellulose synthase.

  3. Beetle and plant arrow poisons of the Ju|'hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae).

    PubMed

    Chaboo, Caroline S; Biesele, Megan; Hitchcock, Robert K; Weeks, Andrea

    2016-01-01

    The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San ("Bushmen") arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called 'click languages' in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|'hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|'hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|'hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  4. Beetle and plant arrow poisons of the Ju|’hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae)

    PubMed Central

    Chaboo, Caroline S.; Biesele, Megan; Hitchcock, Robert K.; Weeks, Andrea

    2016-01-01

    Abstract The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San (“Bushmen”) arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called ‘click languages’ in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|’hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|’hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|’hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  5. The Cranked Arrow Wing Aerodynamics Project (CAWAP) and its Extension to the International Community as CAWAPI: Objectives and Overview

    NASA Technical Reports Server (NTRS)

    Lamar, John E.; Obara, Clifford J.

    2009-01-01

    This paper provides a brief history of the F-16XL-1 aircraft, its role in the High Speed Research (HSR) program and how it was morphed into the Cranked Arrow Wing Aerodynamics Project (CAWAP). Various flight, wind-tunnel and Computational Fluid Dynamics (CFD) data sets were generated during the CAWAP. These unique and open flight datasets for surface pressures, boundary-layer profiles and skin-friction distributions, along with surface flow data, are described and sample data comparisons given. This is followed by a description of how the project became internationalized to be known as Cranked Arrow Wing Aerodynamics Project International (CAWAPI) and is concluded by an introduction to the results of a 5-year CFD predictive study of data.

  6. Terminal deletion of the long arm of chromosome 3 [46,XX,del(3)(q27{r_arrow}qter)

    SciTech Connect

    Chitayat, D.; Babul, R.; Silver, M.M.

    1996-01-02

    We report on a terminal deletion of the long arm of chromosome 3[46,XX,del(3)(q27{r_arrow}qter)] in a female newborn infant who died 45 hours after delivery and had multiple congenital abnormalities including bilateral anophthalmia, congenital heart disease, and abnormal genitalia. The findings are compared to those of four previously reported cases with terminal de (3q). 8 refs., 4 figs., 1 tab.

  7. PAL SPME Arrow--evaluation of a novel solid-phase microextraction device for freely dissolved PAHs in water.

    PubMed

    Kremser, Andreas; Jochmann, Maik A; Schmidt, Torsten C

    2016-01-01

    After more than 25 years, solid-phase microextraction (SPME) has gained widespread acceptance as a well-automatable and flexible microextraction technique, while its instrumental basis remained mostly unchanged. The novel PAL (Prep And Load solution) SPME Arrow combines the advantages of SPME with the benefits of extraction techniques providing larger sorption phase volumes such as stir bar sorptive extraction (SBSE). It thereby avoids the inherent drawbacks of both techniques such as limitations in method automation in the case of SBSE, as well as the small sorption phase volumes and the lacking fiber robustness of classical SPME fibers. This new design is based on a robust stainless steel backbone, carrying, the screw connection to the PAL sampler, the enlarged sorption phase, and an arrow-shaped tip for conservative penetration of septa (hence the name). An outer capillary encloses this phase apart from enrichment and desorption processes and rests against the tip during transfer and penetrations, resulting in a homogeneously closed device. Here, we present an evaluation and a comparison of the novel PAL SPME Arrow with classical SPME fibers, extracting polycyclic aromatic hydrocarbons (PAHs) as model analytes, from the freely dissolved fraction in lab water and groundwater via direct immersion using polydimethylsiloxane (PDMS) as common sorption phase material. Limits of detection, repeatabilities, and extraction yields were determined for the PAL SPME Arrow and compared to data of classical SPME fibers and SBSE bars. Results indicate a significant benefit in extraction efficiency due to the larger sorption phase volume. It is accompanied by faultless mechanical robustness and thus better reliability, especially in case of prolonged, unattended, and automated operation. As an exemplary application, the water-soluble fraction of PAHs and derivatives in a roofing felt sample was quantified. PMID:26677018

  8. Clinical evaluation of meniscus repair with a bioabsorbable arrow: a 2- to 3-year follow-up study.

    PubMed

    Ellermann, A; Siebold, R; Buelow, J U; Sobau, C

    2002-09-01

    In a clinical study with the bioabsorbable Bionx Meniscus Arrow we prospectively evaluated 113 consecutive patients (113 menisci) after all-inside meniscus repair. Repairs were performed in either the medial (80.5%) or lateral (19.5%) posterior horn in the red-red or red-white meniscal zone; 66% of patients underwent concomitant ACL reconstruction. Assessment was based on history, clinical examination, and Lysholm [37] and Cincinnati Knee Scores. After a mean follow-up was 33 months (range 24-43; n=105) 21 (20%) patients showed signs and symptoms consistent with a meniscus tear (16 medial, 5 lateral) and underwent partial meniscectomy. In 11 (52%) of the revised patients concomitant ACL reconstruction was performed; 4 (19%) of revised patients were older than 35 years. In the nonrevised the average Lysholm Score was 92.5 and the average Cincinnati Score 90.4. Two patients showed a distinct femoral cartilage damage. Patient's age did not significantly affect the revision rate. Meniscus repair with the bioabsorbable arrow leads to clinical results comparable to those of traditional suture techniques. When stabilized, patients with concomitant ACL reconstruction showed comparable results to patients without ACL rupture. The simple and time saving all-inside insertion obviates the need for additional incisions and avoids knot tying. A proper tear selection and arrow positioning is necessary and should avoid cartilage damage. PMID:12355303

  9. Contributions to the Dart versus Arrow Debate: New Data from Holocene Projectile Points from Southeastern and Southern Brazil.

    PubMed

    Okumura, Mercedes; Araujo, Astolfo G M

    2015-01-01

    Lithic bifacial points are very common in the southern and southeastern regions of the Brazilian territory. Dated from Early to Late Holocene, these artifacts have not been studied in terms of their propulsion system. Given the characteristics of the bow and arrow compared to the atlatl and dart, there are important differences in the size and weight of arrowheads and dart points. Applying the techniques proposed by Shott (1997), Bradbury (1997), Fenenga (1953), Hughes (1998), and Hildebrandt and King (2012) to specimens recovered from eight sites dating from the early to the late Holocene, this work aims to present preliminary results to better understand the potential presence of darts and arrows in southeastern and southern Brazil. There was a variation in the results according to the application of different techniques. At least one set of points, dated from the Early Holocene, presented quite a high proportion of specimens classified as arrows, indicating the presence of points that could be used as arrowheads. PMID:26648546

  10. Phase Space Approach for S2 arrow S0 internal conversion in the benzene molecule.

    NASA Astrophysics Data System (ADS)

    Kallush, Shimshon; Segev, Bilha; Sergeev, Alexei; Heller, Eric J.

    2000-06-01

    The theoretical problem of finding propensity rules for the partition of energy between competing vibrations in a radiationless vibronic relaxation transition, is converted by the phase-space method of [1,2] to the simple mathematical problem of finding a maximum for a simple function under a constraint. The function is the Wigner function of the initial state and the constraint is energy conservation, defining an accepting energy surface in phase space. We apply this phase space method for finding propensity rules for vibronic transitions when the Frack-Condon factors are exponentially small to the classical example of the benzene molecule. We extend the method to forbidden transitions and include in the analysis non-harmonic force-field effects. Using the phase space analysis, we explain the non-classical behavior of the S_2arrow S0 relaxation of the benzene. Given the energy gap, reasonable displacements and recently calculated force fields [3] we show that almost all the energy must go to C-H stretching. Non-harmonic effects increase in this case the transition rate but do not change the partition of energy between the accepting vibrational modes. [1] E.J. Heller and D. Beck, Chem. Phys. Lett. 202, 350 (1993). [2] B. Segev and E.J. Heller, Journal of Chemical Physics, 112, 4004-4013 (2000). [3] A. Miani, E. Cane, P. Palmieri, A. Trombetti,N.C. Handy, J. Chem. Phys., 112, 248-259 (2000).

  11. Supersonic Aerodynamic Design Improvements of an Arrow-Wing HSCT Configuration Using Nonlinear Point Design Methods

    NASA Technical Reports Server (NTRS)

    Unger, Eric R.; Hager, James O.; Agrawal, Shreekant

    1999-01-01

    This paper is a discussion of the supersonic nonlinear point design optimization efforts at McDonnell Douglas Aerospace under the High-Speed Research (HSR) program. The baseline for these optimization efforts has been the M2.4-7A configuration which represents an arrow-wing technology for the High-Speed Civil Transport (HSCT). Optimization work on this configuration began in early 1994 and continued into 1996. Initial work focused on optimization of the wing camber and twist on a wing/body configuration and reductions of 3.5 drag counts (Euler) were realized. The next phase of the optimization effort included fuselage camber along with the wing and a drag reduction of 5.0 counts was achieved. Including the effects of the nacelles and diverters into the optimization problem became the next focus where a reduction of 6.6 counts (Euler W/B/N/D) was eventually realized. The final two phases of the effort included a large set of constraints designed to make the final optimized configuration more realistic and they were successful albeit with a loss of performance.

  12. ARGX-87: Accident Response Group Exercise, 1987: A Broken Arrow mini exercise. [Training

    SciTech Connect

    Schuld, E.P.; Cruff, D.F.

    1987-07-01

    A Broken Arrow mini exercise dubbed ''Accident Response Group Exercise - 1987'' (ARGX-87) was conducted on June 1, 1987 at the Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories, Livermore (SNLL). The exercise started at 0445 PDT with a call from the Department of Energy (DOE) - EOC in Washington, DC, to the Albuquerque Operations (AL - ) - EOC. AL, in turn, called the Laboratory off-hour emergency number (Fire Dispatcher), who called the Laboratory Emergency Duty Officer (LEDO). The LEDO then contacted the Accident Response Group (ARG) Senior Scientific Advisor. Calls were placed to assemble appropriate members of the ARG in the ALERT Center. No phone number for SNLL was available at the Albuquerque Operations EOC, so a controller injected a message to SNLL to get them involved in the exercise. The messages received at the Laboratory identified the Air Force line item weapon system involved in the accident and the accident location. As people arrived at the ALERT Center they began discussing the details of the accident. They also started working the deployment logistics and other issues. Travel arrangements for the HOT SPOT equipment and ARG personnel were made for immediate deployment to the accident site in North Dakota. The exercise was terminated at 0840 as planned. While certain procedural deficiencies were noted, the exercise was considered a valuable learning experience. The results and observations from this experience will be used to refine the operating procedures and the training program.

  13. Study of advanced composite structural design concepts for an arrow wing supersonic cruise configuration, task 3

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A structural design study was conducted to assess the relative merits of structural concepts using advanced composite materials for an advanced supersonic aircraft cruising at Mach 2.7. The configuration and structural arrangement developed during Task I and II of the study, was used as the baseline configuration. Allowable stresses and strains were established for boron and advanced graphite fibers based on projected fiber properties available in the next decade. Structural concepts were designed and analyzed using graphite polyimide and boron polyimide, applied to stiffened panels and conventional sandwich panels. The conventional sandwich panels were selected as the structural concept to be used on the wing structure. The upper and lower surface panels of the Task I arrow wing were redesigned using high-strength graphite polyimide sandwich panels over the titanium spars and ribs. The ATLAS computer system was used as the basis for stress analysis and resizing the surface panels using the loads from the Task II study, without adjustment for change in aeroelastic deformation. The flutter analysis indicated a decrease in the flutter speed compared to the baseline titanium wing design. The flutter analysis indicated a decrease in the flutter speed compared to the baseline titanium wing design. The flutter speed was increased to that of the titanium wing, with a weight penalty less than that of the metallic airplane.

  14. Threshold responses of Blackside Dace (Chrosomus cumberlandensis) and Kentucky Arrow Darter (Etheostoma spilotum) to stream conductivity

    USGS Publications Warehouse

    Hitt, Nathaniel P.; Floyd, Michael; Compton, Michael; McDonald, Kenneth

    2016-01-01

    Chrosomus cumberlandensis (Blackside Dace [BSD]) and Etheostoma spilotum (Kentucky Arrow Darter [KAD]) are fish species of conservation concern due to their fragmented distributions, their low population sizes, and threats from anthropogenic stressors in the southeastern United States. We evaluated the relationship between fish abundance and stream conductivity, an index of environmental quality and potential physiological stressor. We modeled occurrence and abundance of KAD in the upper Kentucky River basin (208 samples) and BSD in the upper Cumberland River basin (294 samples) for sites sampled between 2003 and 2013. Segmented regression indicated a conductivity change-point for BSD abundance at 343 μS/cm (95% CI: 123–563 μS/cm) and for KAD abundance at 261 μS/cm (95% CI: 151–370 μS/cm). In both cases, abundances were negligible above estimated conductivity change-points. Post-hoc randomizations accounted for variance in estimated change points due to unequal sample sizes across the conductivity gradients. Boosted regression-tree analysis indicated stronger effects of conductivity than other natural and anthropogenic factors known to influence stream fishes. Boosted regression trees further indicated threshold responses of BSD and KAD occurrence to conductivity gradients in support of segmented regression results. We suggest that the observed conductivity relationship may indicate energetic limitations for insectivorous fishes due to changes in benthic macroinvertebrate community composition.

  15. Design study of structural concepts for an arrow-wing supersonic-cruise aircraft

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.; Robinson, J. C.; Yates, E. C., Jr.

    1975-01-01

    An analytical study was performed to determine the best structural approach for design of primary wing and fuselage structure of a Mach number 2.7 arrow-wing supersonic cruise aircraft. Concepts were evaluated considering near-term start-of-design. Emphasis was placed on the complex interactions between thermal stress, static aeroelasticity, flutter, fatigue and fail-safe design, static and dynamic loads, and the effects of variations in structural arrangements, concepts and materials on these interactions. Results indicate that a hybrid wing structure incorporating low-profile convex-beaded and honeycomb sandwich surface panels of titanium alloy 6Al-4V were the most efficient. The substructure includes titanium alloy spar caps reinforced with Boron-polyimide composites. The fuselage shell is a closed-hat stiffened skin and frame construction of titanium alloy 6Al-4V. This paper presents an executive summary of the study effort, and includes a discussion of the overall study logic, design philosophy and interaction between the analytical methods for supersonic cruise aircraft design.

  16. Two-photon excitation of the 4[ital f][sup 1][r arrow]5[ital d][sup 1] transitions of Ce[sup 3+] in LuPO[sub 4] and YPO[sub 4

    SciTech Connect

    Sytsma, J.; Piehler, D.; Edelstein, N.M. ); Boatner, L.A.; Abraham, M.M. )

    1993-06-01

    Two-photon excitation (TPE) spectra of the 4[ital f][sup 1][r arrow]5[ital d][sup 1] transitions of Ce[sup 3+] in LuPO[sub 4] and YPO[sub 4] have been investigated. For Ce[sup 3+] in LuPO[sub 4], transitions to four out of the five 5[ital d][sup 1] levels are observed as zero-phonon lines. The symmetry properties of the levels were obtained from the polarization dependence of the TPE signals. Measurements on Ce[sup 3+] in YPO[sub 4] support the given assignments. Although a crystal-field fit yields a satisfactory rms energy deviation, an unrealistic value of the spin-orbit coupling parameter, [zeta][sub 5[ital d

  17. Evidence of K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}}: The BNL E787 1995 result (How did we get here)

    SciTech Connect

    Chiang, I.H.; E787 Collaboration

    1998-02-01

    The kaon was studied very thoroughly since its discovery some 50 years ago. In the study of charged kaon branching ratios, it was noticed that K{sup +} {r_arrow} {pi}{sup 0}e{sup +}{nu}{sub e} is allowed while K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} is not. The latter was then empirically classified as a forbidden decay, leading to the so called strangeness changing current rule. The decay K{sup +} {r_arrow} {pi}{sup 0}e{sup +}{nu}{sub e} is mediated by the strangeness changing charged current and its branching ratio is 4.8%. By contrast K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} is a strangeness changing neutral current, which is forbidden. In 1970, the GIM model was introduced to explain this effect and in 1974, Gaillard and Lee calculated the K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} branching ratio to be on the order of 10{sup {minus}10}. In the current theory, the K{sup +} {r_arrow} {pi}{sup +}{nu}{anti {nu}} is mediated by a Flavor Changing Neutral Current (FCNC) in which the cancellation of the three quark generations should be complete down to second order except for the difference in the quark masses. The top quark is much heavier than the charm and up quarks, so that the cancellation is not complete. In other words, this decay is more dependent on the top sector. The measurement of K{sup +} {r_arrow}{pi}{sup +}{nu}{anti {nu}} branching ratio measures the modulus of the V{sub td} element of the CKM Matrix. The 1995 results of E787 were published in 1997. This report is focused on how the author achieved the goal of detecting events with such as small branching ratio.

  18. Box-and-arrow explanations need not be more abstract than neuroscientific mechanism descriptions

    PubMed Central

    Datteri, Edoardo; Laudisa, Federico

    2014-01-01

    The nature of the relationship between box-and-arrow (BA) explanations and neuroscientific mechanism descriptions (NMDs) is a key foundational issue for cognitive science. In this article we attempt to identify the nature of the constraints imposed by BA explanations on the formulation of NMDs. On the basis of a case study about motor control, we argue that BA explanations and NMDs both identify regularities that hold in the system, and that these regularities place constraints on the formulation of NMDs from BA analyses, and vice versa. The regularities identified in the two kinds of explanation play a crucial role in reasoning about the relationship between them, and in justifying the use of neuroscientific experimental techniques for the empirical testing of BA analyses of behavior. In addition, we make claims concerning the similarities and differences between BA analyses and NMDs. First, we argue that both types of explanation describe mechanisms. Second, we propose that they differ in terms of the theoretical vocabulary used to denote the entities and properties involved in the mechanism and engaging in regular, mutual interactions. On the contrary, the notion of abstractness, defined as omission of detail, does not help to distinguish BA analyses from NMDs: there is a sense in which BA analyses are more detailed than NMDs. In relation to this, we also focus on the nature of the extra detail included in NMDs and missing from BA analyses, arguing that such detail does not always concern how the system works. Finally, we propose reasons for doubting that BA analyses, unlike NMDs, may be considered “mechanism sketches.” We have developed these views by critically analyzing recent claims in the philosophical literature regarding the foundations of cognitive science. PMID:24904480

  19. Experimental Investigation of a Point Design Optimized Arrow Wing HSCT Configuration

    NASA Technical Reports Server (NTRS)

    Narducci, Robert P.; Sundaram, P.; Agrawal, Shreekant; Cheung, S.; Arslan, A. E.; Martin, G. L.

    1999-01-01

    The M2.4-7A Arrow Wing HSCT configuration was optimized for straight and level cruise at a Mach number of 2.4 and a lift coefficient of 0.10. A quasi-Newton optimization scheme maximized the lift-to-drag ratio (by minimizing drag-to-lift) using Euler solutions from FL067 to estimate the lift and drag forces. A 1.675% wind-tunnel model of the Opt5 HSCT configuration was built to validate the design methodology. Experimental data gathered at the NASA Langley Unitary Plan Wind Tunnel (UPWT) section #2 facility verified CFL3D Euler and Navier-Stokes predictions of the Opt5 performance at the design point. In turn, CFL3D confirmed the improvement in the lift-to-drag ratio obtained during the optimization, thus validating the design procedure. A data base at off-design conditions was obtained during three wind-tunnel tests. The entry into NASA Langley UPWT section #2 obtained data at a free stream Mach number, M(sub infinity), of 2.55 as well as the design Mach number, M(sub infinity)=2.4. Data from a Mach number range of 1.8 to 2.4 was taken at UPWT section #1. Transonic and low supersonic Mach numbers, M(sub infinity)=0.6 to 1.2, was gathered at the NASA Langley 16 ft. Transonic Wind Tunnel (TWT). In addition to good agreement between CFD and experimental data, highlights from the wind-tunnel tests include a trip dot study suggesting a linear relationship between trip dot drag and Mach number, an aeroelastic study that measured the outboard wing deflection and twist, and a flap scheduling study that identifies the possibility of only one leading-edge and trailing-edge flap setting for transonic cruise and another for low supersonic acceleration.

  20. [Fatal head injury caused by a crossbow arrow with unusually preserved posttraumatic volitional activity - case report].

    PubMed

    Řehulka, Hynek; Čechová, Eva; Mottlová, Jitka; Valenta, Martin; Mareška, Zdeněk

    2016-01-01

    The authors deal with a case of suicidal attempt resulting in a fatal head injury. A young man shot himself with a serially produced mechanical sports crossbow. The young man with a critical intracranial injury, a penetration, was nevertheless capable of basic locomotive activity, as well as of coherent communication with another people present at the scene. The critically injured patient was transported from the scene directly to medical centre where he subsequently underwent a neurologic surgery. On the eight day after the incident he died in the hospital as a result of sustained wounds. During the autopsy, a penetrating arrow-shot wound head injury was certified, occurring in the right and left temple area. Signs of a complex decompressive craniectomy were established too. The shooting channel was generally horizontally oriented, extending from the right to the left side, from behind in a 10 up to 15 degrees angle to the frontal plane, penetrating the brain from the right temple lobe and the frontal lobe, thereby pervading also frontal horns of lateral ventricles, and from the left afflicting the frontal lobe on the left side of the brain. In the course of the shooting channel, brain contusion occurred, accompanied by intraventricular haemorrhage. In addition, a heavy cerebral oedema, multiple secondary malacias, Durett haemorrhages and extensive thrombosis of cerebral sinuses were stated. In the course of police investigation, based mainly on the information given by the wounded man right after he had been found at the scene, it was revealed that another person might have been involved. The forensic autopsy, the investigation of the Police and the subsequent criminalist-ballistics expert investigation, supported by a series of experimental substitutive target shots, didnt, however, decidedly prove that any other culprit had been involved. PMID:27108656

  1. Search for anomalous WW/WZ {r_arrow} e{nu}jj production at D0; Busqueda de produccion anomala WW/WZ {r_arrow}e{nu}jj en D-Zero

    SciTech Connect

    Hernandez, A.S.

    1997-02-01

    A search for anomalous WW and WZ production in p{anti p} collisions at {radical}s = 1.8 TeV using the D0 detector at Fermilab is presented. With a data sample of p{anti p} {r_arrow} e{nu}jjX events corresponding to an integrated luminosity of 76.5 {+-} 4.1pb{sup {minus}1}. 399 candidate events were identified, from which 387.1 {+-} 39.8 events were estimated to be background. No deviations from the Standard Model were seen, which predicts 16.2 {+-} 2.7 events. The 95% CL limit on the cross section {sigma}(p{anti p} {r_arrow} W{sup +}W{sup {minus}}X) was calculated to be 93.8 pb. Limits on the CP-conserving anomalous WW{sub {gamma}} and WWZ coupling parameters were obtained from a binned likelihood fit to the transverse momentum spectrum of the W boson. Assuming that the WW{sub {gamma}} and WWZ coupling parameters are equal, the 95% CL limits on the CP-conserving couplings are {minus}0.56 < {Delta}{kappa} < 0.75 (with {lambda} = 0) and {minus}0.42 < {lambda} < 0.44 (with {Delta}{kappa} = 0), for a form factor scale {Lambda}{sub FF} = 1.5 TeV. Limits on other assumptions are also reported. These results were combined with the previous D0 WW, WZ {r_arrow} e{nu}jj published results (13.7 {+-} 0.7 pb{sup {minus}1}), and the limits on the anomalous coupling parameters were set to {minus}0.44 < {Delta}{kappa} < 0.60 (with {lambda} = 0) and {minus}0.34 < {lambda} 0.37 (with {Delta}{kappa} = 0), for a form factor scale {Lambda}{sub FF} = 2.0 TeV.

  2. Histochemical demonstration of a rhodopsin-like substance in the eye of the arrow-worm, Spadella schizoptera (Chaetognatha).

    PubMed

    Goto, T; Yoshida, M

    1988-01-01

    The presumed photoreceptive region of the arrow-worms of the species Sagitta crassa and Spadella schizoptera consists of perforated lamellae which are unique as the photoreceptive structure. The existence of a visual pigment in this region was demonstrated by a histofluorescent technique using Spadella schizoptera, whose presumed photoreceptive region was much larger than in Sagitta crassa. A specific fluorescence, indicative of the presence of retinal-based proteins, appeared only in the perforated lamellar region. The result suggests that the perforated lamellae contain a rhodopsin-like substance and could be the primary photoreceptive site. PMID:3268423

  3. CHARGE association in a child with de novo inverted duplication (14) (q22{r_arrow}q24.3)

    SciTech Connect

    North, K.N.; Wu, Bai Lin; Cao, B.N.

    1995-07-17

    We report on a 4-{1/2} year old girl with apparent CHARGE association who had a de novo inverted duplication (14) (q22{r_arrow}24.3), iris colobomas, ventricular septal defect, soft tissue choanal atresia, intellectual impairment, growth retardation, sensorineural deafness, apparently low set ears, and upslanting palpebral fissures. Family history was unremarkable and parental chromosomes were normal. Similarities between this and previously reported cases of 14q duplication suggest that a locus for a gene or genes causing some of the anomalies of CHARGE association may reside in the region 14q22 to 24.3. 26 refs., 2 figs., 1 tab.

  4. The 5 f r arrow 6 d absorption spectrum of Pa sup 4+ /Cs sub 2 ZrCl sub 6

    SciTech Connect

    Edelstein, N.; Kot, W.K. ); Krupa, J. )

    1992-01-01

    The 5{ital f}{sup 1}{r arrow}6{ital d}{sup 1} absorption spectrum of {sup 231}Pa{sup 4+} diluted in a single crystal of Cs{sub 2}ZrCl{sub 6} has been measured at 4.2 K. Three bands corresponding to the 6{ital d}({Gamma}{sub 8{ital g}}, {Gamma}{sub 7{ital g}}, and {Gamma}{sup {prime}}{sub 8{ital g}} ) levels are assigned. Extensive vibronic structure has been observed for the lowest 5{ital f}{r arrow}6{ital d} transition and this structure is compared to that recently reported for the 6{ital d}{sup 1}{r arrow}5{ital f}{sup 1} emission spectra in the same system.

  5. Non-intentional but not automatic: reduction of word- and arrow-based compatibility effects by sound distractors in the same categorical domain.

    PubMed

    Miles, James D; Proctor, Robert W

    2009-10-01

    In the current study, we show that the non-intentional processing of visually presented words and symbols can be attenuated by sounds. Importantly, this attenuation is dependent on the similarity in categorical domain between the sounds and words or symbols. Participants performed a task in which left or right responses were made contingent on the color of a centrally presented target that was either a location word (LEFT or RIGHT) or a left or right arrow. Responses were faster when they were on the side congruent with the word or arrow. This bias was reduced for location words by a neutral spoken word and for arrows by a tone series, but not vice versa. We suggest that words and symbols are processed with minimal attentional requirements until they are categorized into specific knowledge domains, but then become sensitive to other information within the same domain regardless of the similarity between modalities. PMID:19688202

  6. Barcoding of arrow worms (Phylum Chaetognatha) from three oceans: genetic diversity and evolution within an enigmatic phylum.

    PubMed

    Jennings, Robert M; Bucklin, Ann; Pierrot-Bults, Annelies

    2010-01-01

    Arrow worms (Phylum Chaetognatha) are abundant planktonic organisms and important predators in many food webs; yet, the classification and evolutionary relationships among chaetognath species remain poorly understood. A seemingly simple body plan is underlain by subtle variation in morphological details, obscuring the affinities of species within the phylum. Many species achieve near global distributions, spanning the same latitudinal bands in all ocean basins, while others present disjunct ranges, in some cases with the same species apparently found at both poles. To better understand how these complex evolutionary and geographic variables are reflected in the species makeup of chaetognaths, we analyze DNA barcodes of the mitochondrial cytochrome oxidase c subunit I (COI) gene, from 52 specimens of 14 species of chaetognaths collected mainly from the Atlantic Ocean. Barcoding analysis was highly successful at discriminating described species of chaetognaths across the phylum, and revealed little geographical structure. This barcode analysis reveals hitherto unseen genetic variation among species of arrow worms, and provides insight into some species relationships of this enigmatic group. PMID:20376348

  7. Development, integration, testing, and evaluation of the U.S. Army Buckeye System to the NAVAIR Arrow UAV

    NASA Astrophysics Data System (ADS)

    Fischer, Robert L.; Kennedy, Brian G.; Jones, Mitchell; Walker, Jeffrey; Muresan, Darian; Baxter, Gregory; Flood, Mark; Follmer, Brian; Sun, Xiuhong; Chen, William; Ruby, Jeffrey G.

    2008-04-01

    The Buckeye high-resolution geospatial collection system is currently supporting operations within both Iraq and Afghanistan. The Buckeye system, originally developed by the U.S. Army Corps of Engineers (USACE), Engineer Research and Development Center (ERDC), provides timely tactical high resolution geospatial information to field commanders. The Buckeye system is applicable in the following arenas: intelligence, surveillance, and reconnaissance (ISR), mapping, change detection, mission rehearsal, simulation, and battlefield visualization. Three distinct Buckeye systems hosted on multiple air platforms have provided continuous geospatial data delivery to U.S. Forces since November 2004. Further capability is to be provided by integrating next generation Buckeye components to an Unmanned Aerial Vehicle (UAV). The UAV selected for this effort is the experimental Arrow Unmanned Aerial System (UAS). This paper describes the physical and systems integration of the Buckeye Electro-Optical (EO) and Light Detection and Ranging (LIDAR) components to the Arrow platform. Engineering solutions for mass balancing, thermal dispersion, and component calibration are presented. The distributed on-board architecture which performs instrument control, image compression, and data downlink, is described and discussed. Finally theoretical, laboratory and flight testing results are presented with a discussion on implementation and data dissemination within a tactical environment.

  8. Boom Softening and Nacelle Integration on an Arrow-Wing High-Speed Civil Transport Concept

    NASA Technical Reports Server (NTRS)

    Mack, Robert J.

    1999-01-01

    point of view, this concept was unacceptable from several practical and structural considerations. Preliminary wind-tunnel pressure signature data from the LB-16 wind-tunnel model, which had the engine nacelles mounted under the wings (the usual location), indicated that the application of the Langley nacelle-integration method had been only partially successful in the reduction of the nacelle-volume with nacelle-wing interference-lift pressure disturbances. So, "boom softening" had to also address the task of successful integration of the engine nacelles, with the engines in the required under-the-wing location. Unless this problem was solved, low-sonic-boom and low-drag modifications to the wing planform, the airfoil shape, and the fuselage longitudinal area distribution could be nullified if the nacelle disturbances added increments to the nose-shock strengths that were removed through component tailoring. In this paper, an arrow-wing boom-softened HSC7 concept which incorporated modifications to a baseline McDonnell Douglas concept is discussed. The analysis of the concept's characteristics will include estimates of weight, center of gravity, takeoff field length, mission range, and predictions of its ground-level sonic-boom pressure signature. Additional modifications which enhanced the softened-boom performance of this concept are also described as well as estimates of the performance penalties induced by these modifications.

  9. A Method for Writing Open-Ended Curved Arrow Notation Questions for Multiple-Choice Exams and Electronic-Response Systems

    ERIC Educational Resources Information Center

    Ruder, Suzanne M.; Straumanis, Andrei R.

    2009-01-01

    A critical stage in the process of developing a conceptual understanding of organic chemistry is learning to use curved arrow notation. From this stems the ability to predict reaction products and mechanisms beyond the realm of memorization. Since evaluation (i.e., testing) is known to be a key driver of student learning, it follows that a new…

  10. Role of tensor meson pole and {Delta} exchange diagrams in {ital p{bar p}}{r_arrow}{pi}{sup +}{pi}{sup {minus}}

    SciTech Connect

    Yan, Y.; Tegen, R.

    1996-09-01

    The {bar {ital N}}{ital N}{r_arrow}{pi}{pi} annihilation reaction is investigated in a model with both baryon-exchange diagrams and meson-pole diagrams. The main features of the observed differential cross sections for {bar {ital p}}{ital p}{r_arrow}{pi}{sup +}{pi}{sup {minus}} from 360 to 1190 MeV/{ital c} are well understood in this model. The backward enhancement of the differential cross section is mainly due to the {ital N}{Delta}{pi} tensor coupling while the process {bar {ital p}}{ital p}{r_arrow}{ital f}{sub 2}{r_arrow}{pi}{sup +}{pi}{sup {minus}} contributes to the bump structure around 100{degree} developing for {ital P}{sub lab}{approx_gt}680 MeV/{ital c}. This hints at nontrivial quark spin contributions beyond the {sup 3}{ital P}{sub 0} model (which favored {ital S} and {ital P} waves) and hints at a large gluonic component in tensor mesons with masses between 1.27 and 2.2 GeV. {copyright} {ital 1996 The American Physical Society.}

  11. 78 FR 21345 - In the Matter of: Liem Duc Huynh, a/k/a Duc Huynh, 2905 South Elm, Broken Arrow, OK 74012; Order...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE Bureau of Industry and Security In the Matter of: Liem Duc Huynh, a/k/a Duc Huynh, 2905 South Elm, Broken... last known address at: 2905 South Elm, Broken Arrow, OK 74012, and when acting for or on behalf...

  12. Implementing Quality Criteria in Designing and Conducting a Sequential Quan [right arrow] Qual Mixed Methods Study of Student Engagement with Learning Applied Research Methods Online

    ERIC Educational Resources Information Center

    Ivankova, Nataliya V.

    2014-01-01

    In spite of recent methodological developments related to quality assurance in mixed methods research, practical examples of how to implement quality criteria in designing and conducting sequential QUAN [right arrow] QUAL mixed methods studies to ensure the process is systematic and rigorous remain scarce. This article discusses a three-step…

  13. CSMP Mathematics for the Intermediate Grades Part IV, Teacher's Guide. The Languages of Strings and Arrows. Geometry and Measurement. Probability and Statistics.

    ERIC Educational Resources Information Center

    CEMREL, Inc., St. Ann, MO.

    This guide represents the final experimental version of a pilot project which was conducted in the United States between 1973 and 1976. The ideas and the manner of presentation are based on the works of Georges and Frederique Papy. They are recognized for having introduced colored arrow drawings ("papygrams") and models of our numeration system…

  14. CSMP Mathematics for the Upper Primary Grades Part I, Teacher's Guide. The Languages of Strings and Arrows. Geometry and Measurement. Workbooks. Final Experimental Version.

    ERIC Educational Resources Information Center

    CEMREL, Inc., St. Ann, MO.

    This guide represents the final experimental version of a pilot project conducted in the Unites States between 1973 and 1976. The ideas and manner of presentation are based on the works of Georges and Frederique Papy. They are recognized as having introduced colored arrow drawings ("papygrams") and models of our numeration system (the Papy…

  15. Evidence for a founder effect for the IVS4 +4 A{r_arrow}T mutation in the Fanconi anemia gene FACC in a Jewish population

    SciTech Connect

    Verlander, P.C.; Kaporis, A.G.; Qian, L.

    1994-09-01

    Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive disorder defined by hypersensitivity of cells to DNA cross-linking agents; a gene for complementation group C(FACC) has been cloned. Two common mutations, IVS4 +4 A{r_arrow}T and 322delG, and several rare mutations have recently been reported in affected individuals. We now report the development of amplification refractory mutation system (ARMS) assays for rapid, non-radioactive detection of these known mutations in FACC. Primer pairs specific for variant sequences were designed, with the 3{prime} terminal base of one primer matching the variant base. PCR products are separated by electrophoresis on 2.5% agarose gels; mutations are indicated by the presence of a band of a specific size. These ARMS assays can be multiplexed to allow screening for all known mutations in two PCR reactions. We have used these assays for detection of FACC mutations in affected individuals in the International Fanconi Anemia Registry (IFAR), and for carrier detection FACC families. IVS4 +4 A{r_arrow}T is the only FACC mutation found in Jewish FA patients and their families, of both Ashkenazi and Sephardic ancestry. This mutation was not found in any affected individual of non-Jewish origin. In addition, DNA samples from 1596 healthy Jewish individuals primarily of Ashkenazi ancestry were supplied to us by Dor Yeshorim. These samples, ascertained for carrier screening for Tay Sachs, cystic fibrosis, and other genetic diseases with a high frequency in the religious Jewish community served by this organization, were tested for both IVS4 +4 A{r_arrow}T and 322delG mutations; seventeen IVS4 +4 A{r_arrow}T are of Sephardic Jewish ancestry. We hypothesize that IVS4 +4 A{r_arrow}T is a very old mutation, predating the divergence of the Ashkenazi and Sephardic populations. Haplotype analysis with microsatellite markers is in progress.

  16. Percutaneous Venous Thrombectomy Using the Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) with Temporary Caval Filtration: In Vitro Investigations

    SciTech Connect

    Wildberger, Joachim Ernst Haage, Patrick; Bovelander, Jan; Pfeffer, Joachim; Weiss, Claudia; Vorwerk, Dierk; Schmitz-Rode, Thomas; Guenther, Rolf W.

    2005-04-15

    Purpose. To evaluate the size and quantity of downstream emboli after thrombectomy using the Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) with or without temporary filtration for extensive iliofemoral and iliocaval thrombi in an in vitro flow model. Methods. Iliocaval thrombi were simulated by clotted bovine blood in a flow model (semilucent silicone tubings, diameter 12-16 mm). Five experimental set-ups were performed 10 times each; thrombus particles and distribution were measured in the effluent. First, after retrograde insertion, mechanical thrombectomy was performed using the PTD alone. Then a modified self-expanding tulip-shaped temporary vena cava stent filter was inserted additionally at the beginning of each declotting procedure and removed immediately after the intervention without any manipulation within or at the filter itself. In a third step, the filter was filled with thrombus only. Here, two experiments were performed: Careful closure within the flow circuit without any additional fragmentation procedure and running the PTD within the filter lumen, respectively. In the final set-up, mechanical thrombectomy was performed within the thrombus-filled tubing as well as in the filter lumen. The latter was closed at the end of the procedure and both devices were removed from the flow circuit. Results. Running the PTD in the flow circuit without filter protection led to a fragmentation of 67.9% ({+-}7.14%) of the clot into particles {<=}500 {mu}m; restoration of flow was established in all cases. Additional placement of the filter safely allowed maceration of 82.9% ({+-}5.59%) of the thrombus. Controlled closure of the thrombus-filled filter within the flow circuit without additional mechanical treatment broke up 75.2% ({+-}10.49%), while additional mechanical thrombectomy by running the PTD within the occluded filter led to dissolution of 90.4% ({+-}3.99%) of the initial clot. In the final set-up, an overall fragmentation rate of 99.6% ({+-}0

  17. Atomic sulfur: Frequency measurement of the J = 0 left arrow 1 fine-structure transition at 56.3 microns by laser magnetic resonance

    NASA Technical Reports Server (NTRS)

    Brown, John M.; Evenson, Kenneth M.; Zink, Lyndon R.

    1994-01-01

    The J = 0 left arrow 1 fine-structure transition in atomic sulfur (S I) in its ground (3)P state has been detected in the laboratory by far-infrared laser magnetic resonance. The fine-structure interval has been measured accurately as 5,322,492.9 +/- 2.8 MHz which corresponds to a wavelength of 56.325572 +/- 0.000030 micrometers.

  18. The decay. tau. sup minus r arrow K sup minus K sup +. pi. sup minus. nu. sub. tau. and the. nu. sub. tau. mass

    SciTech Connect

    Gomez-Cadenas, J.J. ); Gonzalez-Garcia, M.C.; Pich, A. Instituto de Fisica Corpuscular, Consejo Superior de Investigaciones Cientificas, Universidad de Valencia, Burjasot )

    1990-11-01

    In this paper, we present a model based on the effective chiral Lagrangian to describe the decay {tau}{sup {minus}}{r arrow}{ital K}{sup {minus}}{ital K}{sup +}{pi}{sup {minus}}{nu}{sub {tau}}. Using our model we study the possible limits on the {nu}{sub {tau}} mass that can be achieved by a high-statistics, high-precision experiment taking data close to the {tau}-pair production threshold.

  19. Study of the f{sub 0}(1500)/f{sub 2}(1565) production in the exclusive annihilation {bar n}p{r_arrow}{pi}{sup +}{pi}{sup +}{pi}{sup {minus}} in flight

    SciTech Connect

    The OBELIX Collaboration

    1998-01-01

    The spin-parity analysis of the {bar n}p{r_arrow}{pi}{sup +}{pi}{sup +}{pi}{sup {minus}} exclusive reaction in flight is presented. The main aim is to study the ({pi}{sup +}{pi}{sup {minus}}) invariant mass spectrum in the region around 1500 MeV. The analysis was performed with a Breit-Wigner parametrization for all the resonant states and, for the scalar sector in the mass region below 1.2 GeV, by means of a K-matrix-like treatment. It clearly shows the need for two states, a scalar one (0{sup ++}) with mass and width (1522{plus_minus}25) MeV and (108{plus_minus}33) MeV, and a tensorial one (2{sup ++}) with mass (1575{plus_minus}18) MeV and width (119{plus_minus}24) MeV, respectively. In addition, the analysis requires the presence of a scalar state at (1280{plus_minus}55) MeV, (323{plus_minus}13) MeV broad, and of a second vectorial one, in addition to the {rho}{sup 0}(770) signal, with mass and width (1348{plus_minus}33) MeV and (275{plus_minus}10) MeV, respectively. {copyright} {ital 1997} {ital The American Physical Society}

  20. The asymptotics of the transition form factor {gamma}{gamma}{sup *} {r_arrow} {pi}{sup 0}

    SciTech Connect

    A.V. Radyushkin; R. Ruskov

    1997-05-01

    In this paper the authors present the result of a direct QCD sum rule calculation of the transition form factor {gamma}{gamma}{sup *} {r_arrow} {pi}{sup 0} in the region of moderately large invariant momentum Q{sup 2} > 1GeV{sup 2} of the virtual photon. In contrast to pQCD, they make no assumptions about the shape of the pion distribution amplitude {var_phi}{sub {pi}}(x). Their results agree with the Brodsky-Lepage proposal that the Q{sup 2}-dependence of this form factor is given by an interpolation between its Q{sup 2}=0 value fixed by the axial anomaly and 1/Q{sup 2} pQCD behavior for large Q{sup 2}, with normalization corresponding to the asymptotic form {var_phi}{sub pi}{sup as}(x)=6 f{sub {pi}}x(1{minus}x) of the pion distribution amplitude. Their prediction for the from factor F{sub {gamma}}{sup *}{gamma}{sup *}{pi}{sup 0}(q{sub 1}{sup 2} = 0,q{sub 2}{sup 2} = {minus}Q{sup 2}) is in good agreement with new CLEO data.

  1. Lessons from two-dimensional QCD ({ital N}{r_arrow}{infinity}): Vacuum structure, asymptotic series, instantons, and all that

    SciTech Connect

    Zhitnitsky, A.R.

    1996-05-01

    We discuss two-dimensional QCD ({ital N}{sub {ital c}}{r_arrow}{infinity}) with fermions in the fundamental as well as adjoint representation. We find factorial growth {approximately}({ital g}{sup 2}{ital N}{sub {ital c}}{pi}){sup 2{ital k}}(2{ital k})!({minus}1){sup {ital k}{minus}1}/(2{pi}){sup 2{ital k}} in the coefficients of the large order perturbative expansion. We argue that this behavior is related to classical solutions of the theory, instantons; thus it has nonperturbative origin. Phenomenologically such a growth is related to highly excited states in the spectrum. We also analyze the heavy-light quark system {ital Q{bar q}} within the operator product expansion (which turns out to be an asymptotic series). Some vacuum condensates {l_angle}{bar {ital q}}({ital x}{sub {mu}}{ital D}{sub {mu}}){sup 2{ital n}}{ital q}{r_angle}{approximately}({ital x}{sup 2}){sup {ital nn}}! which are responsible for this factorial growth are also discussed. We formulate some general puzzles which are not specific for two-dimensional physics, but are inevitable features of any asymptotic expansion. We resolve these apparent puzzles within two-dimensional QCD and we speculate that analogous puzzles might occur in real four-dimensional QCD as well. {copyright} {ital 1996 The American Physical Society.}

  2. New redox-related arrows in the arsenal of cardiac disease treatment.

    PubMed

    Kirk, Jonathan A; Paolocci, Nazareno

    2014-11-10

    While great strides have been made to improve the poor prognosis with cardiac disease, heart failure in particular, cardiac affections still remain the most prevalent, difficult-to-treat, and costly human pathologies in the western world. At rest, the heart produces a significant oxidative environment inside diverse cell compartments, due to its high-energy demand. Cardiac cells have an exquisite control system to deal with this constant redox stress. However, persistent hemodynamic alterations can compromise these mechanisms, fueling further myocardial redox imbalance and dysfunction. Still, this would be a one-sided and incomplete view, because the physiological role of reactive oxygen species (ROS) should be considered as well. Indeed, ROS are multipurpose agents, serving signaling and cell defense tasks too, and, similar to antioxidants, these functions can be highly compartmentalized within the cell. The present Forum was designed to collect cutting-edge research concerning when and how to effectively counter excessive oxidative burden to preserve cardiac structure and/or to improve function, under conditions of ordinary or extraordinary stress. Another major objective was to unravel old and new intersections between different myocardial processes by which ROS may act as "on" or "off" switches, and in doing so, dictating function, always with an eye on possible, immediate therapeutic applications, as suggested by the title of the Forum itself, that is, Cardiac Therapeutics. PMID:25211226

  3. Signal voter

    DOEpatents

    Goodwin, Roy L.

    1981-01-01

    A voter for providing a single accurate output signal that is derived from the closest two signal levels of three input signals, each of which signals represents a measurement of the same phenomena. By means of the voting circuit, the signals are first sorted by level of amplitude and then ranked as highest, middle or lowest. The highest or lowest signal that is furthest from the middle signal is rejected, while the other highest or lowest signal is selected for processing. The selected high or low signal is then averaged with the middle signal to provide the output signal.

  4. Heterogeneous reaction HOCl + HBr {r_arrow} BrCl + H{sub 2}O on ice films

    SciTech Connect

    Chu, L.; Chu, L.T.

    1999-02-11

    Heterogeneous reactions on the surface of polar stratospheric clouds (PSCs) are critical to an understanding of the annual appearance of the Antarctic ozone hole. The heterogeneous reaction HOCl + HBr(s) {r_arrow} BrCl + H{sub 2}O(s) on the ice surface at 189 and 220 K has been investigated in a flow reactor interfaced with a differentially pumped quadrupole mass spectrometer. Pseudo first-order decay of HOCl over the HBr-treated ice surfaces has been determined under the condition of P{sub HOCl} < P{sub HBr}. For the HBr partial pressure in the range of 1.1 {times} 10{sup {minus}7} to 6.6 {times} 10{sup {minus}5} Torr, the reaction probability ({gamma}{sub g}) was determined in the range of 0.06 to 0.38 at 189 K. The reaction probability is in the range of 0.01 to 0.07 at 220 K for HBr partial pressure from 7.2 {times} 10{sup {minus}7} to 1.3 {times} 10{sup {minus}5} Torr. The reaction probability was found to be strongly dependent on the ice surface temperature. The reaction probability is higher at the lower temperature than that at the warmer temperature and a mechanistic explanation is provided. The true reaction probabilities ({gamma}{sub t}) of the reaction were calculated using a pore diffusion model. The kinetic analysis indicates that the heterogeneous reaction of HOCl + HBr may follow the Eley-Rideal type of mechanism. Also, the heat of uptake of HOCl on ice was determined to be about {minus}8.5 {+-} 2 kcal/mol.

  5. Penguin operators in nonresonant B{sup {minus}}{r_arrow}M{bar M}{pi}{sup {minus}}(M={pi}{sup {minus}},K{sup {minus}},K{sup 0}) decays

    SciTech Connect

    Fajfer, S. |; Oakes, R.J.; Pham, T.N.

    1999-09-01

    We investigate the contributions coming from the penguin operators in the nonresonant B{sup {minus}}{r_arrow}M{bar M}{pi}{sup {minus}}(M={pi}{sup {minus}},K{sup {minus}},K{sup 0}) decays. The effective Wilson coefficients of the strong penguin operators O{sub 4} and O{sub 6} are found to be relatively larger than those for other penguin operators. We calculate the contributions arising from the O{sub 4} and O{sub 6} operators in the nonresonant decays B{sup {minus}}{r_arrow}M{bar M}{pi}{sup {minus}}(M={pi}{sup {minus}},K{sup {minus}},{bar K}{sup 0}) using a model combining heavy quark symmetry and the chiral symmetry, developed previously. We find that the CKM-forbidden nonresonant B{sup {minus}}{r_arrow}K{sup 0}{bar K}{sup 0}{pi}{sup {minus}} decay occurs through the strong penguin operators. These penguin contributions affect the branching ratios for B{sup {minus}}{r_arrow}M{bar M}{pi}{sup {minus}}(M={pi}{sup {minus}},K{sup {minus}}) by only a few percent. The branching ratio for B{sup {minus}}{r_arrow}K{sup 0}{bar K}{sup 0}{pi}{sup {minus}} is estimated to be of the order 10{sup {minus}6}. {copyright} {ital 1999} {ital The American Physical Society}

  6. Doubly charged Higgsino contribution to the decays {mu}{r_arrow}e{gamma} and {mu}{r_arrow}3e and to the anomalous magnetic moment of the muon {Delta}a{sub {mu}} within the left-right supersymmetric model

    SciTech Connect

    Couture, G.; Koenig, H.; Frank, M.; Koenig, H.

    1997-10-01

    We present a detailed and complete calculation of the doubly charged Higgsino contribution to the decays {mu}{r_arrow}e{gamma} and {mu}{r_arrow}3e and to the anomalous magnetic moment of the muon {Delta}a{sub {mu}} within the left-right supersymmetric model. We include the mixing of the scalar partners of the left- and right-handed leptons, and show that it leads to a strong enhancement of the decay modes in certain scenarios. We find that the contribution of the doubly charged Higgsino can be close to the known experimental values and is reachable by future experiments. {copyright} {ital 1997} {ital The American Physical Society}

  7. Exact results on e{sup +}e{sup -} {r_arrow}e{sup +}e{sup -} + 2{gamma} at SLC/LEP energies

    SciTech Connect

    Yost, S.A.; Jadach, S.; Ward, B.F.L.

    1993-04-01

    The authors use the spinor methods of the CALKUL collaboration, as realized by Xu, Zhang and Chang, to calculate the differential cross section for e{sup +}e{sup {minus}}{r_arrow}e{sup +}e{sup {minus}} + 2{gamma} for c.m.s. energies in the SLC/LEP regime. An explicit complete formula for the respective cross section is obtained. The leading log approximation is used to check the formula. Applications of the formula to high precision luminosity calculations at SLC/LEP are discussed.

  8. Investigation at Mach Numbers of 0.20 to 3.50 of Blended Wing-Body Combinations of Sonic Design with Diamond, Delta, and Arrow Plan Forms

    NASA Technical Reports Server (NTRS)

    Holdaway, George H.; Mellenthin, Jack A.

    1960-01-01

    The models had aspect-ratio-2 diamond, delta, and arrow wings with the leading edges swept 45.00 deg, 59.04 deg, and 70.82 deg, respectively. The wing sections were computed by varying the section shape along with the body radii (blending process) to match the prescribed area distribution and wing plan form. The wing sections had an average value of maximum thickness ratio of about 4 percent of the local chords in a streamwise direction. The models were tested with transition fixed at Reynolds numbers of about 4,000,000 to 9,000,0000, based on the mean aerodynamic chord of the wings. The effect of varying Reynolds number was checked at both subsonic and supersonic speeds. The diamond model was superior to the other plan forms at transonic speeds ((L/D)max = 11.00 to 9.52) because of its higher lift-curve slope and near optimum wave drag due to the blending process. For the wing thickness tested with the diamond model, the marked body and wing contouring required for transonic conditions resulted in a large wave-drag penalty at the higher supersonic Mach numbers where the leading and trailing edges of the wing were supersonic. Because of the low sweep of the trailing edge of the delta model, this configuration was less adaptable to the blending process. Removing a body bump prescribed by the Mach number 1.00 design resulted in a good supersonic design. This delta model with 10 percent less volume was superior to the other plan forms at Mach numbers of 1.55 to 2.35 ((L/D)max = 8.65 to 7.24), but it and the arrow model were equally good at Mach numbers of 2.50 to 3.50 ((L/D)max - 6.85 to O.39). At transonic speeds the arrow model was inferior because of the reduced lift-curve slope associated with its increased sweep and also because of the wing base drag. The wing base-drag coefficients of the arrow model based on the wing planform area decreased from a peak value of 0.0029 at Mach number 1.55 to 0.0003 at Mach number 3.50. Linear supersonic theory was satisfactory

  9. Simulator study of the low-speed handling qualities of a supersonic cruise arrow-wing transport configuration during approach and landing

    NASA Technical Reports Server (NTRS)

    Grantham, W. D.; Nguyen, L. T.; Neubauer, M. J., Jr.; Smith, P. M.

    1976-01-01

    A fixed-based simulator study was conducted to determine the low-speed flight characteristics of an advanced supersonic cruise transport having an arrow wing, a horizontal tail, and four dry turbojets with variable geometry turbines. The primary piloting task was the approach and landing. The statically unstable (longitudinally) subject configuration has unacceptable low-speed handling qualities with no augmentation. Therefore, a hardened stability augmentation system is required to achieve acceptable handling qualities, should the normal operational stability and control augmentation system fail. In order to achieve satisfactory handling qualities, considerable augmentation was required.

  10. High power n of m{sub b} in b-flavored widths and n={bold 5{r_arrow}{infinity}} limit

    SciTech Connect

    Bigi, I.; Uraltsev, N.; Shifman, M.; Uraltsev, N.; Vainshtein, A.; Uraltsev, N.; Uraltsev, N.; Vainshtein, A.

    1997-10-01

    The leading term in the semileptonic width of heavy flavor hadrons depends on the fifth power of the heavy quark mass. We present an analysis where this power can be self-consistently treated as a free parameter n and the width can be studied in the limit n{r_arrow}{infinity}. The resulting expansion elucidates why the small velmcity (SV) treatment is relevant for the inclusive semileptonic b{r_arrow}c transition. The extended SV limit (ESV limit) is introduced. The leading terms in the perturbative {alpha}{sub s} expansion enhanced by powers of n are automatically resummed by using the low-scale Euclidean mass. The large-n treatment explains why the scales of order m{sub b}/n are appropriate. On the other hand, the scale cannot be too small since the factorially divergent perturbative corrections associated with running of {alpha}{sub s} show up. Both requirements are met if we use the short-distance mass normalized at a scale around m{sub b}/n{approximately}1GeV. A convenient definition of such low-scale operator-product-expansion-compatible masses is briefly discussed. {copyright} {ital 1997} {ital The American Physical Society}

  11. Chiral perturbation theory for K{sup +}{r_arrow}{pi}{sup +}{pi}{sup 0} decay in the continuum and on the lattice

    SciTech Connect

    Golterman, M.F.; Leung, K.C.

    1997-09-01

    In this paper we use one-loop chiral perturbation theory in order to compare lattice computations of the K{sup +}{r_arrow}{pi}{sup +}{pi}{sup 0} decay amplitude with the experimental value. This makes it possible to investigate three systematic effects that plague lattice computations: quenching, finite-volume effects, and the fact that lattice computations have been done at unphysical values of the quark masses and pion external momenta (only this latter effect shows up at the tree level). We apply our results to the most recent lattice computation and find that all three effects are substantial. We conclude that one-loop corrections in chiral perturbation theory help in explaining the discrepancy between lattice results and the real-world value. We also reexamine B{sub K}, which is closely related to the K{sup +}{r_arrow}{pi}{sup +}{pi}{sup 0} decay amplitude by chiral symmetry. {copyright} {ital 1997} {ital The American Physical Society}

  12. Elevated total plasma homocysteine and 667C{r_arrow}T mutation of the 5,10-methylenetetrahydrofolate reductase gene in thrombotic vascular disease

    SciTech Connect

    De Franchis, R.; Sebastio, G.; Andria, G.

    1996-07-01

    Moderate elevation of total plasma homocysteine (tHcy) has been reported as an independent risk factor for thrombotic vascular disease, a well-known multifactorial disorder. Possible genetic causes of elevated tHcy include defects of the sulfur-containing amino acids metabolism due to deficiencies of cystathionine {Beta}-synthase, of 5,10-methylenetetrahydrofolate reductase (MTHFR), and of the enzymes of cobalamin metabolism. An impaired activity of MTHFR due to a thermolabile form of the enzyme has been observed in {le}28% of hyperhomocysteinemic patients with premature vascular disease. More recently, the molecular basis of such enzymatic thermolability has been related to a common mutation of the MTHFR gene, causing a C-to-T substitution at nt 677 (677C{r_arrow}T). This mutation was found in 38% of unselected chromosomes from 57 French Canadian individuals. The homozygous state for the mutation was present in 12% of these subjects and correlated with significantly elevated tHcy. Preliminary evidence indicates that the frequency of homozygotes for the 677C{r_arrow}T mutation may vary significantly in populations from different geographic areas. 5 refs., 2 tabs.

  13. Quantum dynamics with real wave packets, including application to three-dimensional (J=0)D+H{sub 2}{r_arrow}HD+H reactive scattering

    SciTech Connect

    Gray, S.K.; Balint-Kurti, G.G.

    1998-01-01

    We show how to extract {bold S} matrix elements for reactive scattering from just the real part of an evolving wave packet. A three-term recursion scheme allows the real part of a wave packet to be propagated without reference to its imaginary part, so {bold S} matrix elements can be calculated efficiently. Our approach can be applied not only to the usual time-dependent Schr{umlt o}dinger equation, but to a modified form with the Hamiltonian operator {cflx H} replaced by f({cflx H}), where f is chosen for convenience. One particular choice for f, a cos{sup {minus}1} mapping, yields the Chebyshev iteration that has proved to be useful in several other recent studies. We show how reactive scattering can be studied by following time-dependent wave packets generated by this mapping. These ideas are illustrated through calculation of collinear H+H{sub 2}{r_arrow}H{sub 2}+H and three-dimensional (J=0)D+H{sub 2}{r_arrow}HD+D reactive scattering probabilities on the Liu{endash}Siegbahn{endash}Truhlar{endash}Horowitz (LSTH) potential energy surface. {copyright} {ital 1998 American Institute of Physics.}

  14. A six dimensional quantum study for atom{endash}triatom reactions: The H+H{sub 2}O{r_arrow}H{sub 2}+OH reaction

    SciTech Connect

    Zhang, D.H.; Light, J.C.

    1996-03-01

    A time-dependent wave packet method has been developed to study atom{endash}triatom ABC+D{r_arrow}AB+CD reactions in full six dimensions (6D). The approach employs a body-fixed coupled angular momentum basis for three angular coordinates, and three 1D bases for three radial coordinates. It permits the calculation of diatom AB vibrational state resolved total reaction probability for an initial rovibrational state of the triatom ABC. The approach is applied to study the H+H{sub 2}O{r_arrow}H{sub 2}+OH reaction on the modified Schatz{endash}Elgersman potential energy surface. Initial state-selected total reaction probabilities are presented for initial ground and several vibrationally excited states of H{sub 2}O for total angular momentum {ital J}=0, along with the final OH vibrational state distributions. We also report the cross sections for reaction from the initial ground vibrational and the first bending excited states of H{sub 2}O. Comparisons are made between our results and those from other theoretical calculations and experiments. {copyright} {ital 1996 American Institute of Physics.}

  15. Supercruiser Arrow HS-8

    NASA Technical Reports Server (NTRS)

    Lord, Paul; Kao, Edward; Abobo, Joey B.; Collins, Todd A.; Ma, Leong; Murad, Adnan; Naran, Hitesh; Nguyen, Thuan P.; Nuon, Timithy I.; Thomas, Dimitri D.

    1992-01-01

    Technology in aeronautics has advanced dramatically since the last design of a production High Speed Civil Transport (HSCT) aircraft. Newly projected requirements call for a new High Speed Civil Transport aircraft with a range of approximately 550 nm and at least 275 passenger capacity. The aircraft must be affordable and marketable. The new HSCT must be able to sustain long-duration flights and to absorb the abuse of daily operation. The new aircraft must be safe and simple to fly and require a minimum amount of maintenance. This aircraft must meet FAA certification criteria of FAR Part 25 and environmental constraints. Several design configurations were examined and two designs were selected for further investigation. The first design employs the delta planform wings and conventional empennage layout. The other design uses a swing wing layout and conventional empennage. Other engineering challenges, including materials and propulsion are also discussed. At a cruise flight speed between Mach 2.2 and Mach 3.0, no current generation of materials can endure the thermal loading of supersonic flight and satisfy the stringent weight requirements. A new generation of lightweight composite materials must be developed for the HSCT. With the enforcement of stage 3 noise restrictions, these new engines must be able to propel the aircraft and satisfy the noise limit. The engine with the most promise is the variable cycle engine. At low subsonic speeds the engine operates like a turbofan engine, providing the most efficient performance. At higher speeds the variable cycle engine operates as a turbojet power plant. The two large engine manufacturers, General Electric and Pratt & Whitney in the United States, are combining forces to make the variable cycle engine a reality.

  16. A C {r_arrow} T transition at nucleotide 592 accounts for the most frequent mutation of G6PD gene in Taiwanese aboriginal Ami tribe: detection by mutagenically separated PCR (MS-PCR)

    SciTech Connect

    Lin, S.P.; Sun, W.; Chang, J.G.

    1994-09-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest known enzymopathy in Taiwan. It is estimated to affect 3% of our population, and its molecular defects have been characterized recently. There are 9 point mutations identified with a C {r_arrow} T substitution at nucleotide (nt) 592 in exon VI, the least frequently seen (0.8%) of all mutations. To characterize mutations of the G6PD gene in the Ami people, the most populous of Taiwanese minorities, we studied 21 G6PD-deficient Ami infants and their family members. Natural and amplification-created restriction sites were generated by PCR technique with 10 pairs of primers applied for the screening. By studying the first 7 cases, we found an identical C {r_arrow} T transition at nt 592. MS-PCR was then designed to rapidly detect the nt 592 mutation. As a result, 17 infants are disclosed as having the C {r_arrow} T transition at nt 592, and 2 have a G {r_arrow} T substitution at nt 1376, which were finally verified to be derived from a Chinese Min-Nan ancestor. The genetic defect of the remaining 2 infants remains unidentified. This study has shown that MS-PCR is a feasible and highly sensitive technique for screening mutation carriers in pooled DNA samples. The homogeneity of the nt 592 mutation in the Ami people has proved to be a good indicator for anthropological research.

  17. Signal Words

    MedlinePlus

    ... Signal Words? Signal words are found on pesticide product labels, and they describe the acute (short-term) toxicity ... red letters on the front panel of the product label. 2,4 Acute Oral LD 50 Inhalation LC ...

  18. Reduced dimensionality diatom--diatom reactive scattering: Application to a model H sub 2 +A sub 2 r arrow H+HA sub 2 reaction

    SciTech Connect

    Sun, Q.; Bowman, J.M. )

    1990-01-15

    We apply a recently formulated quantum theory of diatom--diatom reactions (Q. Sun and J. M. Bowman, Int. J. Quant. Chem., Quant. Chem. Symp. {bold 23}, 9 (1989)) to a model collinear H{sub 2}+A{sub 2}{r arrow}H+HA{sub 2} reaction, where A has the mass of a hydrogen atom. The theory assumes one diatom bond is nonreactive, and the reactive scattering Hamiltonian is written in terms of hyperspherical and cylindrical coordinates. The potential-energy surface used is the PK2 H+H{sub 2} surface augmented by a harmonic degree of freedom describing the nonreactive A{sub 2}. Details of the formulation and solution of the coupled-channel equations are given, along with convergence tests, and a discussion of the new state-to-state transition probabilities. In particular, the partial quenching of the well-known collinear H+H{sub 2} resonances is noted.

  19. Low-speed wind-tunnel tests of a large scale blended arrow advanced supersonic transport model having variable cycle engines and vectoring exhaust nozzles

    NASA Technical Reports Server (NTRS)

    Parlett, L. P.; Shivers, J. P.

    1976-01-01

    A low-speed wind-tunnel investigation was conducted in a full-scale tunnel to determine the performance and static stability and control characteristics of a large-scale model of a blended-arrow advanced supersonic transport configuration incorporating variable-cycle engines and vectoring exhaust nozzles. Configuration variables tested included: (1) engine mode (cruise or low-speed), (2) engine exit nozzle deflection, (3) leading-edge flap geometry, and (4) trailing-edge flap deflection. Test variables included values of C sub micron from 0 to 0.38, values of angle of attack from -10 degrees to 30 degrees, values of angle of sideslip, from -5 degrees to 5 degrees, and values of Reynolds number, from 3.5 million to 6.8 million.

  20. LASER INDUCED FLUORESCENCE OF TRAPPED MOLECULAR IONS: THE CH{sup +} A{sup 1}{Pi}{l_arrow}X{sup 1}{Sigma}{sup +} SYSTEM

    SciTech Connect

    Grieman, Fred J.; Mahan, Bruce H.; O'Keefe, Anthony; Winn, John S.

    1980-09-01

    The CH{sup +} and CD{sup +} A{sup 1}{Pi}{l_arrow}X{sup 1}{Sigma}{sup +} absorption spectra have been obtained by laser excitation of these fragment ions. The ions are contained in a mass-selective quadrupole ion trap under collision free conditions. The spectra therefore reflect the nascent internal energy distributions of the ions, which were produced by electron impact on CH{sub 4} (CD{sub 4}) or C{sub 2}H{sub 2} (C{sub 2}D{sub 2}). Both parent gases gave virtually identical spectra; large rotational and vibrational excitation was observed. The equipment was also capable of measuring the radiative lifetime of CH{sup +} (CD{sup +}) A{sup 1}{Pi} (v=0), and the measured value, 815 nsec, is found to be in good agreement with theoretical calculations of this quantity.

  1. Low-speed wind-tunnel investigation of a large scale advanced arrow-wing supersonic transport configuration with engines mounted above wing for upper-surface blowing

    NASA Technical Reports Server (NTRS)

    Shivers, J. P.; Mclemore, H. C.; Coe, P. L., Jr.

    1976-01-01

    Tests have been conducted in a full scale tunnel to determine the low speed aerodynamic characteristics of a large scale advanced arrow wing supersonic transport configuration with engines mounted above the wing for upper surface blowing. Tests were made over an angle of attack range of -10 deg to 32 deg, sideslip angles of + or - 5 deg, and a Reynolds number range of 3,530,000 to 7,330,000. Configuration variables included trailing edge flap deflection, engine jet nozzle angle, engine thrust coefficient, engine out operation, and asymmetrical trailing edge boundary layer control for providing roll trim. Downwash measurements at the tail were obtained for different thrust coefficients, tail heights, and at two fuselage stations.

  2. Low-speed wind-tunnel study of the high-angle-of-attack stability and control characteristics of a cranked-arrow-wing fighter configuration

    NASA Technical Reports Server (NTRS)

    Grafton, S. B.

    1984-01-01

    The low-speed, high-angle-of-attack stability and control characteristics of a fighter configuration incorporating a cranked arrow wing were investigated in the Langley 30- by 60-foot tunnel as part of a NASA/General Dynamics cooperative research program to investigate the application of advanced wing designs to combat aircraft. Tests were conducted on a baseline configuration and on several modified configurations. The results show that the baseline configuration exhibited a high level of maximum lift but displayed undesirable longitudinal and lateral-directional stability characteristics at high angles of attack. Various wing modifications were made which improved the longitudinal and lateral-directional stability characteristics of the configuration at high angles of attack. However, most of the modifications were detrimental to maximum lift.

  3. Strong association between a splice mutation (IVS12+5G{r_arrow}A) and haplotype 6 in hereditary tyrosinemia type I

    SciTech Connect

    Tanguay, R.M.; St-Louis, M.; Gibson, K.

    1994-09-01

    Hereditary tyrosinemia type I (HT I; McKusick 276700) is a severe inborn error of tyrosine catabolism pathway caused by a deficiency of fumarylacetoacetate hydrolase (FAH). The highest frequency reported is the one in Saguenay-Lac St-Jean (Quebec, Canada) where 1:1,846 births are affected. The FAH gene has been cloned and several mutations have been described. Allele specific oligonucleotide (ASO) hybridization was used to examine the frequency of a splice (IVS12-5G{r_arrow}A) mutation recently reported and RFLP analysis was done to identify haplotypes related to HT I. The splice mutation was found on 45/50 alleles (90%) in patients from SLSJ and 12/66 (18%) alleles from patients world-wide. All 25 patients from the SLSJ region were positive with 20 being homozygous, indicating that this mutation is the major cause of HT I in French Canada. Of these 25 patients, 96% were positive for one haplotype called no 6 which is these 25 patients, 96% were positive for one haplotype called no 6 which is identified by TaqI, RsaI, BglII, MspI and KpnI digestions. These data show a really strong association between the mutation (IVS12+5G{r_arrow}A) and haplotype 6. Among our patients from around the world, {approximately}52% were positive for haplotype 6 indicating its strong relation with HT I. These results provide the rationale for DNA-based carrier testing for HT I in the F-C population at risk as well as in HT I patients in general.

  4. Phosphoinositide signaling.

    PubMed

    Boss, Wendy F; Im, Yang Ju

    2012-01-01

    "All things flow and change…even in the stillest matter there is unseen flux and movement." Attributed to Heraclitus (530-470 BC), from The Story of Philosophy by Will Durant. Heraclitus, a Greek philosopher, was thinking on a much larger scale than molecular signaling; however, his visionary comments are an important reminder for those studying signaling today. Even in unstimulated cells, signaling pathways are in constant metabolic flux and provide basal signals that travel throughout the organism. In addition, negatively charged phospholipids, such as the polyphosphorylated inositol phospholipids, provide a circuit board of on/off switches for attracting or repelling proteins that define the membranes of the cell. This template of charged phospholipids is sensitive to discrete changes and metabolic fluxes-e.g., in pH and cations-which contribute to the oscillating signals in the cell. The inherent complexities of a constantly fluctuating system make understanding how plants integrate and process signals challenging. In this review we discuss one aspect of lipid signaling: the inositol family of negatively charged phospholipids and their functions as molecular sensors and regulators of metabolic flux in plants. PMID:22404474

  5. Hedgehog signalling.

    PubMed

    Lee, Raymond Teck Ho; Zhao, Zhonghua; Ingham, Philip W

    2016-02-01

    The Hedgehog (Hh) signalling pathway is one of the key regulators of metazoan development. Hh proteins have been shown to play roles in many developmental processes and have become paradigms for classical morphogens. Dysfunction of the Hh pathway underlies a number of human developmental abnormalities and diseases, making it an important therapeutic target. Interest in Hh signalling thus extends across many fields, from evo-devo to cancer research and regenerative medicine. Here, and in the accompanying poster, we provide an outline of the current understanding of Hh signalling mechanisms, highlighting the similarities and differences between species. PMID:26839340

  6. Curly arrows meet electron density transfers in chemical reaction mechanisms: from electron localization function (ELF) analysis to valence-shell electron-pair repulsion (VSEPR) inspired interpretation.

    PubMed

    Andrés, Juan; Berski, Sławomir; Silvi, Bernard

    2016-07-01

    Probing the electron density transfers during a chemical reaction can provide important insights, making possible to understand and control chemical reactions. This aim has required extensions of the relationships between the traditional chemical concepts and the quantum mechanical ones. The present work examines the detailed chemical insights that have been generated through 100 years of work worldwide on G. N. Lewis's ground breaking paper on The Atom and the Molecule (Lewis, G. N. The Atom and the Molecule, J. Am. Chem. Soc. 1916, 38, 762-785), with a focus on how the determination of reaction mechanisms can be reached applying the bonding evolution theory (BET), emphasizing how curly arrows meet electron density transfers in chemical reaction mechanisms and how the Lewis structure can be recovered. BET that combines the topological analysis of the electron localization function (ELF) and Thom's catastrophe theory (CT) provides a powerful tool providing insight into molecular mechanisms of chemical rearrangements. In agreement with physical laws and quantum theoretical insights, BET can be considered as an appropriate tool to tackle chemical reactivity with a wide range of possible applications. Likewise, the present approach retrieves the classical curly arrows used to describe the rearrangements of chemical bonds for a given reaction mechanism, providing detailed physical grounds for this type of representation. The ideas underlying the valence-shell-electron pair-repulsion (VSEPR) model applied to non-equilibrium geometries provide simple chemical explanations of density transfers. For a given geometry around a central atom, the arrangement of the electronic domain may comply or not with the VSEPR rules according with the valence shell population of the considered atom. A deformation yields arrangements which are either VSEPR defective (at least a domain is missing to match the VSEPR arrangement corresponding to the geometry of the ligands), VSEPR compliant

  7. CDF Run II Discovery reach for neutral MSSM higgs bosons via p pbar {right arrow}b b-bar {phi}{right arrow}b b-bar b b-bar

    SciTech Connect

    J.A. Valls

    1999-07-20

    In this paper we examine the CDF Run II discovery reach for neutral Higgs bosons via the process p{anti p} {yields} b {anti b} {phi} {yields} b {anti b}b {anti b}. The signature is a four jet final state with at least three b-tagged jets. Signal and background acceptances are estimated using the CDF Run I detector performance. b tagging efficiencies and fake tag rates are evaluated with new Run II increased detector geometrical acceptances. Total rates are estimated from present Run I data and from Monte Carlo. The results are interpreted within the framework of the minimal supersymmetric extension of the standard model (MSSM) and generalized in terms of a model independent enhancement factor.

  8. The expanding clinical phenotype of the tRNA{sup Leu(UUR)} A{r_arrow}G mutation at np 3243 of mitochondrial DNA: Diabetic embryopathy associated with mitochondrial cytopathy

    SciTech Connect

    Feigenbaum, A.; Chitayat, D.; Robinson, B.; MacGregor, D.; Myint, T.

    1996-04-24

    We describe a family which demonstrates and expands the extreme clinical variability now known to be associated with the A{r_arrow}G transition at nucleotide position 3243 of the mitochondrial DNA. The propositus presented at birth with clinical manifestations consistent with diabetic embryopathy including anal atresia, caudal dysgenesis, and multicystic dysplastic kidneys. His co-twin was normal at birth, but at 3 months of life, presented with intractable seizures later associated with developmental delay. The twins` mother developed diabetes mellitus type I at the age of 20 years and gastrointestinal problems at 22 years. Since age 19 years, the maternal aunt has had recurrent strokes, seizures, mental deterioration and deafness, later diagnosed as MELAS syndrome due to the tRNA{sup Leu(UUR)} A{r_arrow}G mutation. A maternal uncle had diabetes mellitus type I, deafness, and normal intellect, and died at 35 years after recurrent strokes. This pedigree expands the known clinical phenotype associated with tRNA{sup Leu(UUR)} A{r_arrow}G mutation and raises the possibility that, in some cases, diabetic embryopathy may be due to a mitochondrial cytopathy that affects both the mother`s pancreas (and results in diabetes mellitus and the metabolic dysfunction associated with it) and the embryonic/fetal and placental tissues which make the embryo more vulnerable to this insult. 33 refs., 1 tab.

  9. De novo partial duplication 7(q11.2{r_arrow}q21.2) in a dysmorphic, developmentally retarded boy

    SciTech Connect

    Ross, M.; Pinsky, L.; Teebi, A.

    1994-09-01

    Chromosomal abnormalities involving chromosome 7q are rare; we report a case of partial duplication 7q. The propositus was born at 34 weeks by cesarian section, decided because of oligohydramnios, severe intrauterine growth retardation and fetal immobility. At birth, the baby was under the 5th percentile for height, weight and head circumference and had dysmorphic features, including slight asymmetry of the face, bilateral epicanthus, hypoplastic nasal bridge, short globular nose, asymmetrical dysplastic ears, fifth finger clinodactyly, short second and fifth toe. Ultrasound examination showed atrial and ventricular septal defects. At 18 months, the child had a fracture of the femur, secondary to a minor trauma; skeletal X-rays showed generalized osteoporosis and normal healing. The karyotype with GTG-banding showed a de novo partial duplication of the long arm of chromosome 7 (46,XX,dup(7)(q11.23{r_arrow}q21.2)). Fluorescence in situ hybridization with a painting probe specific for chromosome 7 confirmed the intra-chromosomal rearrangement. The patient`s phenotype and his chromosomal abnormality do not match the previously reported cases of partial trisomy 7q. This case confirms the importance of FISH for the delineation of the chromosomal inbalance in structural chromosomal aberrations.

  10. Assignment of human potassium channel gene KCNA4 (Kv1. 4, PCN2) to chromosome 11q13. 4 [r arrow] q14. 1

    SciTech Connect

    Philipson, L.H.; Bell, G.I. ); Eddy, R.L.; Shows, T.B. )

    1993-02-01

    Both electrically excitable and nonexcitable tissues express voltage-sensitive K[sup +] channels. Since the original isolation of the Drosophila Shaker gene encoding voltage-sensitive K[sub +] channels, five additional related gene families have been described: the Shal, Shab, and Shaw families and the K-eag and Slo genes. A seventh family of slowly activating K[sup +] channels, minK of IsK, is structurally unrelated to the others. Seven human genes related to the Shaker subfamily have been described. We recently described the cloning of a fast-inactivating human voltage-gated K[sup +] channel, PCN2. Here we report the mapping of the gene encoding PNC2, designated KNCA4, to chromosome 11 by analyzing its segregation in a panel of reduced human-mouse somatic cell hybrids. In situ hybridization to prometaphase chromoxomes localized KCNA4 to the long arm of chromosome 11 in the region of bands q13.4 [r arrow] q14.1.

  11. Quantum state-to-state reaction probabilities for the H+H{sub 2}O{r_arrow}H{sub 2}+OH reaction in six dimensions

    SciTech Connect

    Zhang, D.H.; Light, J.C.

    1996-07-01

    A time-dependent wave packet method has been employed to calculate the state-to-state reaction probability for the H+H{sub 2}O(0,0,0){r_arrow}H{sub 2}({ital v}{sub 1},{ital j}{sub 1})+OH({ital v}{sub 2},{ital j}{sub 2}) reaction for {ital J}=0 and initial nonrotating H{sub 2}O on the modified Schatz{endash}Elgersman potential energy surface in full six dimensions (6D). Starting from a wave packet for an atom{endash}triatom asymptotic state in atom{endash}triatom Jacobi coordinates, we transfer the wave packet to diatom{endash}diatom Jacobi coordinates after the wave packet moves into the interaction region. Propagation is then carried out in the diatom{endash}diatom Jacobi coordinates until the reaction flux measured in the diatom{endash}diatom asymptotic region is converged. {copyright} {ital 1996 American Institute of Physics.}

  12. A new look at the ventral nerve centre of Sagitta: implications for the phylogenetic position of Chaetognatha (arrow worms) and the evolution of the bilaterian nervous system

    PubMed Central

    Harzsch, Steffen; Müller, Carsten HG

    2007-01-01

    Background The Chaetognatha (arrow worms) are a group of marine carnivores whose phylogenetic relationships are still vigorously debated. Molecular studies have as yet failed to come up with a stable hypothesis on their phylogenetic position. In a wide range of metazoans, the nervous system has proven to provide a wealth of characters for analysing phylogenetic relationships (neurophylogeny). Therefore, in the present study we explored the structure of the ventral nerve centre ("ventral ganglion") in Sagitta setosa with a set of histochemical and immunohistochemical markers. Results In specimens that were immunolabeled for acetylated-alpha tubulin the ventral nerve centre appeared to be a condensed continuation of the peripheral intraepidermal nerve plexus. Yet, synapsin immunolocalization showed that the ventral nerve centre is organized into a highly ordered array of ca. 80 serially arranged microcompartments. Immunohistochemistry against RFamide revealed a set of serially arranged individually identifiable neurons in the ventral nerve centre that we charted in detail. Conclusion The new information on the structure of the chaetognath nervous system is compared to previous descriptions of the ventral nerve centre which are critically evaluated. Our findings are discussed with regard to the debate on nervous system organisation in the last common bilaterian ancestor and with regard to the phylogenetic affinities of this Chaetognatha. We suggest to place the Chaetognatha within the Protostomia and argue against hypotheses which propose a deuterostome affinity of Chaetognatha or a sister-group relationship to all other Bilateria. PMID:17511857

  13. The prediction of pressure distributions on an arrow-wing configuration including the effect of camber, twist, and a wing fin

    NASA Technical Reports Server (NTRS)

    Bobbitt, P. J.; Manro, M. E.; Kulfan, R. M.

    1980-01-01

    Wind tunnel tests of an arrow wing body configuration consisting of flat, twisted, and cambered twisted wings were conducted at Mach numbers from 0.40 to 2.50 to provide an experimental data base for comparison with theoretical methods. A variety of leading and trailing edge control surface deflections were included in these tests, and in addition, the cambered twisted wing was tested with an outboard vertical fin to determine its effect on wing and control surface loads. Theory experiment comparisons show that current state of the art linear and nonlinear attached flow methods were adequate at small angles of attack typical of cruise conditions. The incremental effects of outboard fin, wing twist, and wing camber are most accurately predicted by the advanced panel method PANAIR. Results of the advanced panel separated flow method, obtained with an early version of the program, show promise that accurate detailed pressure predictions may soon be possible for an aeroelasticity deformed wing at high angles of attack.

  14. Meaurement of the target single-spin asymmetry in quasi-elastic region from the reaction {sup 3}He{up_arrow}(e,e')

    SciTech Connect

    Zhang, Yawei

    2013-10-01

    A measurement of the inclusive target single-spin asymmetry has been performed using the quasi-elastic {sup 3}He{up_arrow}(e,e') reaction with a vertically polarized {sup 3}He target at Q{sup 2} values of 0.13, 0.46 and 0.97 GeV{sup 2}. This asymmetry vanishes under the one photon exchange assumption. But the interference between two-photon exchange and one-photon exchange gives rise to an imaginary amplitude, so that a non-zero A{sub y} is allowed. The experiment, conducted in Hall A of Jefferson Laboratory in 2009, used two independent spectrometers to simultaneously measure the target single-spin asymmetry. Using the effective polarization approximation, the neutron single-spin asymmetries were extracted from the measured {sup 3}He asymmetries. The measurement is to establish a non-vanishing A{sub y}. Non-zero asymmetries were observed at all Q{sup 2} points, and the overall precision is an order of magnitude improved over the existing proton data. The data provide new constraints on Generalized Parton Distribution (GPD) models and new information on the dynamics of the two-photon exchange process.

  15. Search for B_c^± arrow J/ψ μ^± X Decays in pbarp Collisions at √s=1.8 TeV

    NASA Astrophysics Data System (ADS)

    Singh, Prem

    1997-04-01

    The B_c^± meson, a bound state of charm and bottom quarks, is expected to have several narrow mass states below the B--D open flavor threshold. We describe a search for the weak decays of the B_c^± produced in a 110 pb-1 sample of √s= 1.8 TeV proton-antiproton collisions in the CDF detector at the Fermilab Tevatron. A high branching ratio of B_c^± to J/ψ decays permits an effective trigger on these events. The search is conducted through the decay B_c^± arrow J/ψ μ^± X. Supported by U.S. DOE under Contract No. DE-FG02-91ER40646. We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Science and Culture of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; and the A. P. Sloan Foundation.

  16. Gibberellin signaling.

    PubMed

    Hartweck, Lynn M

    2008-12-01

    This review covers recent advances in gibberellin (GA) signaling. GA signaling is now understood to hinge on DELLA proteins. DELLAs negatively regulate GA response by activating the promoters of several genes including Xerico, which upregulates the abscisic acid pathway which is antagonistic to GA. DELLAs also promote transcription of the GA receptor, GIBBERELLIN INSENSITIVE DWARF 1 (GID1) and indirectly regulate GA biosynthesis genes enhancing GA responsiveness and feedback control. A structural analysis of GID1 provides a model for understanding GA signaling. GA binds within a pocket of GID1, changes GID1 conformation and increases the affinity of GID1 for DELLA proteins. GA/GID1/DELLA has increased affinity for an F-Box protein and DELLAs are subsequently degraded via the proteasome. Therefore, GA induces growth through degradation of the DELLAs. The binding of DELLA proteins to three of the PHYTOCHROME INTERACTING FACTOR (PIF) proteins integrates light and GA signaling pathways. This binding prevents PIFs 3, 4, and 5 from functioning as positive transcriptional regulators of growth in the dark. Since PIFs are degraded in light, these PIFs can only function in the combined absence of light and presence of GA. New analyses suggest that GA signaling evolved at the same time or just after the plant vascular system and before plants acquired the capacity for seed reproduction. An analysis of sequences cloned from Physcomitrella suggests that GID1 and DELLAs were the first to evolve but did not initially interact. The more recently diverging spike moss Selaginella has all the genes required for GA biosynthesis and signaling, but the role of GA response in Selaginella physiology remains a mystery. PMID:18936962

  17. A precision measurement of the Z{sup 0} lineshape parameters for the process Z{sup 0} {r_arrow} {tau}{sup +}{tau}{sup {minus}}

    SciTech Connect

    Lahmann, R.

    1996-12-31

    In this dissertation, a measurement of the partial decay width of the process Z{sup 0} {r_arrow} {tau}{sup +}{tau}{sup {minus}} using data collected during 1993 and 1994 at the OPAL detector at CERN is described. The cross sections of this process at three center-of-mass energies near the Z{sup 0} resonance were determined, and from a fit to those cross sections, the mass of the Z{sup 0}, its total decay width and its partial decay width into {tau}{sup +}{tau}{sup {minus}} final states were determined as M{sub Z} = 91.183 {+-} 0.020 GeV, {Lambda}{sub tot} = 2.514 {+-} 0.018 GeV and {Lambda}{sub {tau}{tau}} = 84.54 {+-} 0.59 MeV. Using published results for M{sub Z}, and {Lambda}{sub tot} with higher accuracy, a value for the partial decay width of {Lambda}{sub {tau}{tau}} = 84.02 {+-} 0.20 MeV was obtained. Further using published results for the decay width of the Z{sup 0} into quark pair final states, the invisible decay width of the Z{sup 0} was determined as {Lambda}{sub inv} = 496.9 {+-} 4.1 MeV, and the number of neutrino generations was determined as N{sub {nu}} = 2.974 {+-} 0.025(exp) {+-} 0.007 (m{sub top}, M{sub Higgs}). All results were found to be in good agreement with the Standard Model predictions and were consistent with the assumption of lepton universality within the Standard Model framework.

  18. Kinetics of the transformation from {alpha}{r_arrow}{gamma} during continuous heating and cooling in a Ti-47.5 at.% Al alloy

    SciTech Connect

    Veeraraghavan, D.; Vasudevan, V.K.

    1995-12-31

    The {alpha}{r_arrow}{gamma} transformation in a Ti-47.5 At.% Al alloys was studied by a novel computer interfaced control-cum-data acquisition technique. In situ, real time, high speed simultaneous measurements of resistivity and temperature were made in the system designed and constructed for this purpose. The experiments were conducted in high vacuum. The samples were heated to the completely {alpha}-region by controlled direct resistance heating and cooled at various rates utilizing a varying helium gas jet quench. Temperature and resistivity changes were monitored during heating and cooling and correlated with corresponding phase/microstructural changes. The results have shown that the {gamma} phase is characterized by a low resistivity ({approximately}50 {micro}{Omega}-cm at room temperature), whereas both {alpha} and {alpha}{sub 2} phases have high and nearly constant resistivities ({approximately}190 to 200{micro}{Omega}-cm). Because of the large difference in resistivities of the {alpha} and {gamma} phases, large and measurable changes in resistivity can be observed when one of these phases transforms to the other. In the Ti-47.5 Al alloy, the lamellar {gamma} morphology was observed at slower cooling rates, the feathery/massive reaction at intermediate rates and a massive morphology at high cooling rates. Results of the transformation start and completion temperatures for the various reactions as a function of cooling rate are presented. The growth rate of the massive product was determined to vary from 4 {times} 10{sup {minus}3} to 6.5 {times} 10{sup {minus}3} m/s with increasing undercooling.

  19. Predicting the intensity mapping signal for multi-J CO lines

    NASA Astrophysics Data System (ADS)

    Mashian, Natalie; Sternberg, Amiel; Loeb, Abraham

    2015-11-01

    We present a novel approach to estimating the intensity mapping signal of any CO rotational line emitted during the Epoch of Reionization (EoR). Our approach is based on large velocity gradient (LVG) modeling, a radiative transfer modeling technique that generates the full CO spectral line energy distribution (SLED) for a specified gas kinetic temperature, volume density, velocity gradient, molecular abundance, and column density. These parameters, which drive the physics of CO transitions and ultimately dictate the shape and amplitude of the CO SLED, can be linked to the global properties of the host galaxy, mainly the star formation rate (SFR) and the SFR surface density. By further employing an empirically derived SFR-M relation for high redshift galaxies, we can express the LVG parameters, and thus the specific intensity of any CO rotational transition, as functions of the host halo mass M and redshift z. Integrating over the range of halo masses expected to host CO-luminous galaxies, we predict a mean CO(1-0) brightness temperature ranging from ~ 0.6 μK at z = 6 to ~ 0.03 μK at z = 10 with brightness temperature fluctuations of ΔCO2 ~ 0.1 and 0.005 μK respectively, at k = 0.1 Mpc-1. In this model, the CO emission signal remains strong for higher rotational levels at z = 6, with langle TCO rangle ~ 0.3 and 0.05 μK for the CO J = 6arrow5 and CO J = 10arrow9 transitions respectively. Including the effects of CO photodissociation in these molecular clouds, especially at low metallicities, results in the overall reduction in the amplitude of the CO signal, with the low- and high-J lines weakening by 2-20% and 10-45%, respectively, over the redshift range 4 < z < 10.

  20. Rate constants for the reactions H+O sub 2 r arrow OH+O and D+O sub 2 r arrow OD+O over the temperature range 1085--2278 K by the laser photolysis--shock tube technique

    SciTech Connect

    Shin, K.S.; Michael, J.V. )

    1991-07-01

    Rate constants for the reactions (1) H+O{sub 2}{r arrow}OH+O and (2) D+O{sub 2}{r arrow}OD+O have been measured over the temperature ranges 1103--2055 K and 1085--2278 K, respectively. The experimental method that has been used is the laser-photolysis--shock-tube technique. This technique utilizes atomic resonance absorption spectrophotometry (ARAS) to monitor H- or D-atom depletion in the presence of a large excess of reactant, O{sub 2}. The results can be well represented by the Arrhenius expressions {ital k}{sub 1}({ital T})=(1.15{plus minus}0.16){times}10{sup {minus}10} exp({minus}6917{plus minus}193 K/{ital T}) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}, and {ital k}{sub 2}({ital T})=(1.09{plus minus}0.20){times}10{sup {minus}10} exp({minus}6937{plus minus}247 K/{ital T}) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. Over the experimental temperature range, the present results show that the isotope effect is unity within experimental uncertainty. The Arrhenius equations, {ital k}{sub {minus}1}({ital T})=(8.75{plus minus}1.24) {times}10{sup {minus}12} exp(1121{plus minus}193 K/{ital T}) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1} and {ital k}{sub {minus}2} ({ital T})=(9.73{plus minus}1.79){times}10{sup {minus}12} exp(526{plus minus}247 K/{ital T}) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}, for the rate constants of the reverse reactions were calculated from the experimentally measured forward rate constants and expressions for the equilibrium constants that have been derived from the JANAF thermochemical database. The theoretical implications of the present results are also discussed.

  1. Effect of leading-edge contour and vertical-tail configuration on the low-speed stability characteristics of a supersonic transport model having a highly-swept arrow wing

    NASA Technical Reports Server (NTRS)

    Lockwood, V. E.

    1978-01-01

    A low-speed investigation was made on a highly-swept arrow-wing model to determine the effect of wing leading-edge contour and vertical-tail configuration on the aerodynamic characteristics in pitch and sideslip. The investigation was made with the trailing-edge flaps deflected over a range of angles of attack from 8 deg to 32 deg. The tests were made at a Mach number of 0.13, which corresponds to a Reynolds number of about 3,000,000 based on the wing reference chord.

  2. Low-speed wind-tunnel tests of a 1/10-scale model of an advanced arrow-wing supersonic cruise configuration designed for cruise at Mach 2.2. [Langley Full Scale Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Yip, L. P.

    1979-01-01

    The low-speed longitudinal and lateral-directional characteristics of a scale model of an advanced arrow-wing supersonic cruise configuration were investigated in tests conducted at a Reynolds number of 4.19 x 10 to the 6th power based on the mean aerodynamic chord, with an angle of attack range from - 6 deg to 23 deg and sideslip angle range from -15 deg to 20 deg. The effects of segmented leading-edge flaps, slotted trailing-edge flaps, horizontal and vertical tails, and ailerons and spoilers were determined. Extensive pressure data and flow visualization pictures with non-intrusive fluorescent mini-tufts were obtained.

  3. Absolute Rovibrational Intensities, Self-Broadening and Self-Shift Coefficients for the X(sup 1) Sigma(+) V=3 (left arrow) V=0 Band (C-12)(O-16)

    NASA Technical Reports Server (NTRS)

    Chackerian, Charles, Jr.; Freedman, R.; Giver, L. P.; Brown, L. R.

    2001-01-01

    The rotationless transition moment squared for the x(sup 1) sigma (sup +) v=3 (left arrow) v=0 band of CO is measured to be the absolute value of R (sub 3-0) squared = 1.7127(25)x 10(exp -7) Debye squared. This value is about 8.6 percent smaller than the value assumed for HITRAN 2000. The Herman-Wallis intensity factor of this band is F=1+0.01168(11)m+0.0001065(79)m squared. The determination of self-broadening coefficients is improved with the inclusion of line narrowing; self-shifts are also reported.

  4. Systemic silencing signal(s).

    PubMed

    Fagard, M; Vaucheret, H

    2000-06-01

    Grafting experiments have revealed that transgenic plants that undergo co-suppression of homologous transgenes and endogenous genes or PTGS of exogenous transgenes produce a sequence-specific systemic silencing signal that is able to propagate from cell to cell and at long distance. Similarly, infection of transgenic plants by viruses that carry (part of) a transgene sequence results in global silencing (VIGS) of the integrated transgenes although viral infection is localized. Systemic PTGS and VIGS strongly resemble recovery from virus infection in non-transgenic plants, leading to protection against secondary infection in newly emerging leaves and PTGS of transiently expressed homologous transgenes. The sequence-specific PTGS signal is probably a transgene product (for example, aberrant RNA) or a secondary product (for example, RNA molecules produced by an RNA-dependent RNA polymerase with transgene RNA as a matrix) that mimics the type of viral RNA that is targeted for degradation by cellular defence. Whether some particular cases of transgene TGS could also rely on the production of such a mobile molecule is discussed. PMID:10999411

  5. The Unaimed Arrow Never Misses.

    PubMed

    Kopan, Raphael

    2016-01-01

    In this assay, Raphael Kopan argues that focused emphasis on disease and translation stifles innovation, and outline the reasons why, in my opinion, developmental biologists are more likely to produce new and important discoveries than their more "focused" colleagues. PMID:26970640

  6. The language of the arrows

    NASA Astrophysics Data System (ADS)

    2015-10-01

    I think and hope that most experienced physics and astronomy teachers would agree that teaching is both a science and a creative art. There is a way to creatively introduce vectors into introductory astronomy that lets students learn some basic, but fundamental, physics and at the same time demonstrates that mathematics need not be a barrier in a science course. The approach is entirely graphical in that it is based on the geometric properties of vectors and is implemented by drawing diagrams. Despite the simplicity, it allows astronomy students to experience genuine physics reasoning at about the same level of a conceptual physics course (and possibly a higher level).

  7. Time's arrow and Boltzmann's entropy.

    NASA Astrophysics Data System (ADS)

    Lebowitz, J. L.

    For the purpose of this article, the author's motion of time is essentially the Newtonian one - time is real and the basic laws of physics are time reversible, the connect the states of a physical system, possibly of the whole universe, at different instants of time. This of course does not take account of relativity, special or general, and is therefore certainly not the whole story. Still the author believes that the phenomenon they wish to explain, namely the time asymmetric behavior of macroscopic objects, would be for all practical purposes the same in a non-relativistic universe. He therefore focuses here on idealized versions of the problem, in the simplest context, and then sees how far the answers the author gets go towards its solutions.

  8. LED traffic lights: New technology signals major energy savings

    SciTech Connect

    Houghton, D.

    1994-12-31

    Using light-emitting diode technology to replace incandescent lamps in traffic signals promises energy savings upwards of 60 percent for each of the estimated quarter of a million controlled intersections in the United States. LED units use only 9 to 25 watts instead of the 67 to 150 watts used by each incandescent lamp. Though their first cost is relatively high, energy savings result in paybacks of 1 to 5 years. LED retrofit kits are available for red signal disks and arrows, and installations in several states have proven successful, although minor improvements are addressing concerns about varying light output and controller circuitry. Retrofitting green lamps is not yet feasible, because color standards of the Institute of Traffic Engineers cannot be met with existing LED technology. Yellow lamps have such low duty factors (they`re on only 3 percent of the time) that retrofitting with LED signals is not cost-effective. LEDs last much longer than incandescents, allowing municipalities to not only reduce their electricity bills, but to save on maintenance costs as well. As further incentive, some utilities are beginning to implement rebate programs for LED traffic signal retrofits. Full approval of LED units is still awaited from the Institute of Traffic Engineers (ITE), the standard-setting body for traffic safety devices. Local and state governments ultimately decide what specifications to require for traffic lights, and the growing body of successful field experience with LEDs appears to be raising their comfort level with the technology. The California Department of Transportation is developing an LED traffic light specification, and two California utilities, Southern California Edison and Pacific Gas and Electric, have provided rebates for some pilot installations.

  9. Acquisition signal transmitter

    NASA Technical Reports Server (NTRS)

    Friedman, Morton L. (Inventor)

    1989-01-01

    An encoded information transmitter which transmits a radio frequency carrier that is amplitude modulated by a constant frequency waveform and thereafter amplitude modulated by a predetermined encoded waveform, the constant frequency waveform modulated carrier constituting an acquisition signal and the encoded waveform modulated carrier constituting an information bearing signal, the acquisition signal providing enhanced signal acquisition and interference rejection favoring the information bearing signal. One specific application for this transmitter is as a distress transmitter where a conventional, legislated audio tone modulated signal is transmitted followed first by the acquisition signal and then the information bearing signal, the information bearing signal being encoded with, among other things, vehicle identification data. The acquistion signal enables a receiver to acquire the information bearing signal where the received signal is low and/or where the received signal has a low signal-to-noise ratio in an environment where there are multiple signals in the same frequency band as the information bearing signal.

  10. Inhibitors of endocytosis prevent Wnt/Wingless signalling by reducing the level of basal β-catenin/Armadillo.

    PubMed

    Gagliardi, Maria; Hernandez, Ana; McGough, Ian J; Vincent, Jean-Paul

    2014-11-15

    A key step in the canonical Wnt signalling pathway is the inhibition of GSK3β, which results in the accumulation of nuclear β-catenin (also known as CTNNB1), and hence regulation of target genes. Evidence suggests that endocytosis is required for signalling, yet its role and the molecular understanding remains unclear. A recent and controversial model suggests that endocytosis contributes to Wnt signalling by causing the sequestration of the ligand-receptor complex, including LRP6 and GSK3 to multivesicular bodies (MVBs), thus preventing GSK3β from accessing β-catenin. Here, we use specific inhibitors (Dynasore and Dyngo-4a) to confirm the essential role of endocytosis in Wnt/Wingless signalling in human and Drosophila cells. However, we find no evidence that, in Drosophila cells or wing imaginal discs, LRP6/Arrow traffics to MVBs or that MVBs are required for Wnt/Wingless signalling. Moreover, we show that activation of signalling through chemical blockade of GSK3β is prevented by endocytosis inhibitors, suggesting that endocytosis impacts on Wnt/Wingless signalling downstream of the ligand-receptor complex. We propose that, through an unknown mechanism, endocytosis boosts the resting pool of β-catenin upon which GSK3β normally acts. PMID:25236598

  11. Inhibitors of endocytosis prevent Wnt/Wingless signalling by reducing the level of basal β-catenin/Armadillo

    PubMed Central

    Gagliardi, Maria; Hernandez, Ana; McGough, Ian J.; Vincent, Jean-Paul

    2014-01-01

    ABSTRACT A key step in the canonical Wnt signalling pathway is the inhibition of GSK3β, which results in the accumulation of nuclear β-catenin (also known as CTNNB1), and hence regulation of target genes. Evidence suggests that endocytosis is required for signalling, yet its role and the molecular understanding remains unclear. A recent and controversial model suggests that endocytosis contributes to Wnt signalling by causing the sequestration of the ligand–receptor complex, including LRP6 and GSK3 to multivesicular bodies (MVBs), thus preventing GSK3β from accessing β-catenin. Here, we use specific inhibitors (Dynasore and Dyngo-4a) to confirm the essential role of endocytosis in Wnt/Wingless signalling in human and Drosophila cells. However, we find no evidence that, in Drosophila cells or wing imaginal discs, LRP6/Arrow traffics to MVBs or that MVBs are required for Wnt/Wingless signalling. Moreover, we show that activation of signalling through chemical blockade of GSK3β is prevented by endocytosis inhibitors, suggesting that endocytosis impacts on Wnt/Wingless signalling downstream of the ligand–receptor complex. We propose that, through an unknown mechanism, endocytosis boosts the resting pool of β-catenin upon which GSK3β normally acts. PMID:25236598

  12. Signal transfer within a cultured asymmetric cortical neuron circuit

    NASA Astrophysics Data System (ADS)

    Isomura, Takuya; Shimba, Kenta; Takayama, Yuzo; Takeuchi, Akimasa; Kotani, Kiyoshi; Jimbo, Yasuhiko

    2015-12-01

    Objective. Simplified neuronal circuits are required for investigating information representation in nervous systems and for validating theoretical neural network models. Here, we developed patterned neuronal circuits using micro fabricated devices, comprising a micro-well array bonded to a microelectrode-array substrate. Approach. The micro-well array consisted of micrometre-scale wells connected by tunnels, all contained within a silicone slab called a micro-chamber. The design of the micro-chamber confined somata to the wells and allowed axons to grow through the tunnels bidirectionally but with a designed, unidirectional bias. We guided axons into the point of the arrow structure where one of the two tunnel entrances is located, making that the preferred direction. Main results. When rat cortical neurons were cultured in the wells, their axons grew through the tunnels and connected to neurons in adjoining wells. Unidirectional burst transfers and other asymmetric signal-propagation phenomena were observed via the substrate-embedded electrodes. Seventy-nine percent of burst transfers were in the forward direction. We also observed rapid propagation of activity from sites of local electrical stimulation, and significant effects of inhibitory synapse blockade on bursting activity. Significance. These results suggest that this simple, substrate-controlled neuronal circuit can be applied to develop in vitro models of the function of cortical microcircuits or deep neural networks, better to elucidate the laws governing the dynamics of neuronal networks.

  13. Small Angle Neutron Scattering Studies of the Vortex Lattice in the UPt{sub 3} Mixed State: Direct Structural Evidence for the {ital B}{r_arrow}{ital C} Transition

    SciTech Connect

    Yaron, U.; Gammel, P.; Boebinger, G.; Aeppli, G.; Schiffer, P.; Bucher, E.; Bishop, D.; Broholm, C.; Mortensen, K.

    1997-04-01

    Small angle neutron scattering studies of the flux line lattice (FLL) in UPt{sub 3} for fields {bold H}{perpendicular}{bold c} provide direct microscopic evidence for the 5kOe B{r_arrow}C transition. We find a pronounced maximum in the longitudinal correlation length of the FLL at the transition and an abrupt change in the field dependence of the scattered intensity which can be interpreted as a 15{percent} decrease in the coherence length and a 9{percent} increase in the penetration depth, consistent with discontinuities in the critical fields. Finally, in the low field phase, the FLL distortion evolves roughly linearly with field, while in the high field phase it appears to be less field dependent. {copyright} {ital 1997} {ital The American Physical Society}

  14. Transonic pressure measurements and comparison of theory to experiment for an arrow-wing configuration. Volume 1: Experimental data report, base configuration and effects of wing twist and leading-edge configuration. [wind tunnel tests, aircraft models

    NASA Technical Reports Server (NTRS)

    Manro, M. E.; Manning, K. J. R.; Hallstaff, T. H.; Rogers, J. T.

    1975-01-01

    A wind tunnel test of an arrow-wing-body configuration consisting of flat and twisted wings, as well as a variety of leading- and trailing-edge control surface deflections, was conducted at Mach numbers from 0.4 to 1.1 to provide an experimental pressure data base for comparison with theoretical methods. Theory-to-experiment comparisons of detailed pressure distributions were made using current state-of-the-art attached and separated flow methods. The purpose of these comparisons was to delineate conditions under which these theories are valid for both flat and twisted wings and to explore the use of empirical methods to correct the theoretical methods where theory is deficient.

  15. Absolute cross sections for near-threshold electron-impact excitation of the 2s{sup 2}S{r_arrow}2p{sup 2}P transition in C{sup 3+}

    SciTech Connect

    Bannister, M.E.; Chung, Y.; Djuric, N.; Wallbank, B.; Woitke, O.; Zhou, S.; Dunn, G.H.; Smith, A.C.

    1998-01-01

    Absolute total cross sections for electron-impact excitation of the 2s{sup 2}S{r_arrow}2p{sup 2}P transition in C{sup 3+} were measured from 7.35 eV to 8.45 eV using the merged electron-ion-beams energy-loss technique. The results settle the discrepancy between two previous experiments using the crossed-beams fluorescence method, being in very good agreement with the older results [P. O. Taylor, D. Gregory, G. H. Dunn, R. A. Phaneuf, and D. H. Crandall, Phys. Rev. Lett. {bold 39}, 1256 (1977)] but less so with the more recent ones [D. W. Savin, L. D. Gardner, D. B. Reisenfeld, A. R. Young, and J. L. Kohl, Phys. Rev. A {bold 51}, 2162 (1995)]. The present measurements are also in good agreement with unitarized Coulomb-Born and close-coupling calculations. {copyright} {ital 1998} {ital The American Physical Society}

  16. Large tree-level {ital CP} violation in {ital e}{sup +}{ital e}{sup {minus}}{r_arrow}{ital t{bar t}H}{sup 0} in the two-Higgs-doublet model

    SciTech Connect

    Bar-Shalom, S.; Atwood, D.; Eilam, G.; Mendel, R.R.; Soni, A. ||

    1996-02-01

    We find a large {ital CP} violation effect within the two-Higgs-doublet model for the reaction {ital e}{sup +}{ital e}{sup {minus}}{r_arrow}{ital t}{bar {ital t}}{ital H}{sup 0} at future linear colliders. The {ital CP} asymmetry arises already at the tree level as a result of interference between diagrams with {ital H}{sup 0} emission from {ital t} (and {bar {ital t}}) and its emission from a {ital Z}{sup 0} and can be about 10{endash}20 {percent}. In the best case one needs a few hundred {ital t{bar t}H}{sup 0} events to observe {ital CP} violation at the 3{sigma} level. {copyright} {ital 1996 The American Physical Society.}

  17. Identification and molecular confirmation of a small chromosome 10q duplication [dir dup(10)(q24.2 {r_arrow}q24.3)] inherited from a mother mosiac for the abnormality

    SciTech Connect

    Tonk, V.; Schneider, N.R.; Schultz, R.A.; Delgado, M.R.; Mao, Jen-i

    1996-01-02

    We describe a family in which two siblings exhibited developmental delay, reduced muscle tone and mild muscle weakness. Cytogenetic evaluation demonstrated that both children had a tandem duplication of a small portion of the long arm of chromosome 10 [46,XX or XY, dir dup(10)(q24.2{r_arrow}q24.3)], inherited from their clinically normal mother, who was found to be mosaic for the duplicated chromosome 10. Fluorescence in situ hybridization approaches, including total chromosome painting and the use of regional specific cosmid probes, were used to confirm the chromosome 10q origin of the duplicated material. This is the smallest confirmed duplication of this portion of chromosome 10 reported to date. 28 refs., 4 figs.

  18. Low-speed wind-tunnel tests of a one-tenth-scale model of a blended-arrow advanced supersonic transport. [conducted in Langley full-scale tunnel

    NASA Technical Reports Server (NTRS)

    Lemore, H. C.; Parett, L. P.

    1975-01-01

    Tests were conducted in the Langley full scale tunnel to determine the low-speed aerodynamic characteristics of a 1/10 scale model of a blended-arrow advanced supersonic transport. Tests were made for the clean configuration and a high-lift configuration with several combinations of leading- and trailing-edge flaps deflected for providing improved lift and longitudinal stability in the landing and takeoff modes. The tests were conducted for a range of angles of attack from about -6 deg to 30 deg, sideslip angles from -5 deg to 10 deg, and for Reynolds numbers from 6.78 x 1,000,000 to 13.85 x 1,000,000 corresponding to test velocities of 41 knots to 85 knots, respectively.

  19. Signal processor for processing ultrasonic receiver signals

    DOEpatents

    Fasching, George E.

    1980-01-01

    A signal processor is provided which uses an analog integrating circuit in conjunction with a set of digital counters controlled by a precision clock for sampling timing to provide an improved presentation of an ultrasonic transmitter/receiver signal. The signal is sampled relative to the transmitter trigger signal timing at precise times, the selected number of samples are integrated and the integrated samples are transferred and held for recording on a strip chart recorder or converted to digital form for storage. By integrating multiple samples taken at precisely the same time with respect to the trigger for the ultrasonic transmitter, random noise, which is contained in the ultrasonic receiver signal, is reduced relative to the desired useful signal.

  20. Wingless signaling and the control of cell shape in Drosophila wing imaginal discs.

    PubMed

    Widmann, Thomas J; Dahmann, Christian

    2009-10-01

    The control of cell morphology is important for shaping animals during development. Here we address the role of the Wnt/Wingless signal transduction pathway and two of its target genes, vestigial and shotgun (encoding E-cadherin), in controlling the columnar shape of Drosophila wing disc cells. We show that clones of cells mutant for arrow (encoding an essential component of the Wingless signal transduction pathway), vestigial or shotgun undergo profound cell shape changes and are extruded towards the basal side of the epithelium. Compartment-wide expression of a dominant-negative form of the Wingless transducer T-cell factor (TCF/Pangolin), or double-stranded RNA targeting vestigial or shotgun, leads to abnormally short cells throughout this region, indicating that these genes act cell autonomously to maintain normal columnar cell shape. Conversely, overexpression of Wingless, a constitutively-active form of the Wingless transducer beta-catenin/Armadillo, or Vestigial, results in precocious cell elongation. Co-expression of Vestigial partially suppresses the abnormal cell shape induced by dominant-negative TCF. We conclude that Wingless signal transduction plays a cell-autonomous role in promoting and maintaining the columnar shape of wing disc cells. Furthermore, our data suggest that Wingless controls cell shape, in part, through maintaining vestigial expression. PMID:19627985

  1. Signal verification can promote reliable signalling

    PubMed Central

    Broom, Mark; Ruxton, Graeme D.; Schaefer, H. Martin

    2013-01-01

    The central question in communication theory is whether communication is reliable, and if so, which mechanisms select for reliability. The primary approach in the past has been to attribute reliability to strategic costs associated with signalling as predicted by the handicap principle. Yet, reliability can arise through other mechanisms, such as signal verification; but the theoretical understanding of such mechanisms has received relatively little attention. Here, we model whether verification can lead to reliability in repeated interactions that typically characterize mutualisms. Specifically, we model whether fruit consumers that discriminate among poor- and good-quality fruits within a population can select for reliable fruit signals. In our model, plants either signal or they do not; costs associated with signalling are fixed and independent of plant quality. We find parameter combinations where discriminating fruit consumers can select for signal reliability by abandoning unprofitable plants more quickly. This self-serving behaviour imposes costs upon plants as a by-product, rendering it unprofitable for unrewarding plants to signal. Thus, strategic costs to signalling are not a prerequisite for reliable communication. We expect verification to more generally explain signal reliability in repeated consumer–resource interactions that typify mutualisms but also in antagonistic interactions such as mimicry and aposematism. PMID:24068354

  2. Retroactive Signaling in Short Signaling Pathways

    PubMed Central

    Sepulchre, Jacques-Alexandre; Merajver, Sofía D.; Ventura, Alejandra C.

    2012-01-01

    In biochemical signaling pathways without explicit feedback connections, the core signal transduction is usually described as a one-way communication, going from upstream to downstream in a feedforward chain or network of covalent modification cycles. In this paper we explore the possibility of a new type of signaling called retroactive signaling, offered by the recently demonstrated property of retroactivity in signaling cascades. The possibility of retroactive signaling is analysed in the simplest case of the stationary states of a bicyclic cascade of signaling cycles. In this case, we work out the conditions for which variables of the upstream cycle are affected by a change of the total amount of protein in the downstream cycle, or by a variation of the phosphatase deactivating the same protein. Particularly, we predict the characteristic ranges of the downstream protein, or of the downstream phosphatase, for which a retroactive effect can be observed on the upstream cycle variables. Next, we extend the possibility of retroactive signaling in short but nonlinear signaling pathways involving a few covalent modification cycles. PMID:22848403

  3. Signal verification can promote reliable signalling.

    PubMed

    Broom, Mark; Ruxton, Graeme D; Schaefer, H Martin

    2013-11-22

    The central question in communication theory is whether communication is reliable, and if so, which mechanisms select for reliability. The primary approach in the past has been to attribute reliability to strategic costs associated with signalling as predicted by the handicap principle. Yet, reliability can arise through other mechanisms, such as signal verification; but the theoretical understanding of such mechanisms has received relatively little attention. Here, we model whether verification can lead to reliability in repeated interactions that typically characterize mutualisms. Specifically, we model whether fruit consumers that discriminate among poor- and good-quality fruits within a population can select for reliable fruit signals. In our model, plants either signal or they do not; costs associated with signalling are fixed and independent of plant quality. We find parameter combinations where discriminating fruit consumers can select for signal reliability by abandoning unprofitable plants more quickly. This self-serving behaviour imposes costs upon plants as a by-product, rendering it unprofitable for unrewarding plants to signal. Thus, strategic costs to signalling are not a prerequisite for reliable communication. We expect verification to more generally explain signal reliability in repeated consumer-resource interactions that typify mutualisms but also in antagonistic interactions such as mimicry and aposematism. PMID:24068354

  4. Multiplexing oscillatory biochemical signals.

    PubMed

    de Ronde, Wiet; ten Wolde, Pieter Rein

    2014-04-01

    In recent years it has been increasingly recognized that biochemical signals are not necessarily constant in time and that the temporal dynamics of a signal can be the information carrier. Moreover, it is now well established that the protein signaling network of living cells has a bow-tie structure and that components are often shared between different signaling pathways. Here we show by mathematical modeling that living cells can multiplex a constant and an oscillatory signal: they can transmit these two signals simultaneously through a common signaling pathway, and yet respond to them specifically and reliably. We find that information transmission is reduced not only by noise arising from the intrinsic stochasticity of biochemical reactions, but also by crosstalk between the different channels. Yet, under biologically relevant conditions more than 2 bits of information can be transmitted per channel, even when the two signals are transmitted simultaneously. These observations suggest that oscillatory signals are ideal for multiplexing signals. PMID:24685537

  5. Sending Signals Dynamically

    PubMed Central

    Smock, Robert G.; Gierasch, Lila M.

    2010-01-01

    Proteins mediate transmission of signals along intercellular and intracellular pathways and between the exterior and the interior of a cell. The dynamic properties of signaling proteins are crucial to their functions. We discuss emerging paradigms for the role of protein dynamics in signaling. A central tenet is that proteins fluctuate among many states on evolutionarily selected energy landscapes. Upstream signals remodel this landscape, causing signaling proteins to transmit information to downstream partners. New methods provide insight into the dynamic properties of signaling proteins at the atomic scale. The next stages in the signaling hierarchy—how multiple signals are integrated and how cellular signaling pathways are organized in space and time—present exciting challenges for the future, requiring bold multidisciplinary approaches. PMID:19359576

  6. ERK Signals: Scaffolding Scaffolds?

    PubMed Central

    Casar, Berta; Crespo, Piero

    2016-01-01

    ERK1/2 MAP Kinases become activated in response to multiple intra- and extra-cellular stimuli through a signaling module composed of sequential tiers of cytoplasmic kinases. Scaffold proteins regulate ERK signals by connecting the different components of the module into a multi-enzymatic complex by which signal amplitude and duration are fine-tuned, and also provide signal fidelity by isolating this complex from external interferences. In addition, scaffold proteins play a central role as spatial regulators of ERKs signals. In this respect, depending on the subcellular localization from which the activating signals emanate, defined scaffolds specify which substrates are amenable to be phosphorylated. Recent evidence has unveiled direct interactions among different scaffold protein species. These scaffold-scaffold macro-complexes could constitute an additional level of regulation for ERK signals and may serve as nodes for the integration of incoming signals and the subsequent diversification of the outgoing signals with respect to substrate engagement. PMID:27303664

  7. Signal sciences workshop proceedings

    SciTech Connect

    Candy, J.V.

    1997-05-01

    This meeting is aimed primarily at signal processing and controls. The technical program for the 1997 Workshop includes a variety of efforts in the Signal Sciences with applications in the Microtechnology Area a new program at LLNL and a future area of application for both Signal/Image Sciences. Special sessions organized by various individuals in Seismic and Optical Signal Processing as well as Micro-Impulse Radar Processing highlight the program, while the speakers at the Signal Processing Applications session discuss various applications of signal processing/control to real world problems. For the more theoretical, a session on Signal Processing Algorithms was organized as well as for the more pragmatic, featuring a session on Real-Time Signal Processing.

  8. Large {ital CP} asymmetries in {ital B}{sup {plus_minus}}{r_arrow}{eta}{sub {ital c}}({chi}{sub {ital c}0}){pi}{sup {plus_minus}} from the {eta}{sub {ital c}}({chi}{sub {ital c}0}) width

    SciTech Connect

    Eilam, G.; Gronau, M.; Mendel, R.R.

    1995-06-19

    We study {ital CP} asymmetries in {ital B}{sup {plus_minus}}{r_arrow}{ital h}{pi}{sup {plus_minus}} decays, where the hadronic states {ital h}={rho}{rho}, {ital K{bar K}}{pi}, {pi}{sup +}{pi}{sup {minus}}{ital K}{sup +}{ital K}{sup {minus}}, etc., and {ital h}={pi}{sup +}{pi}{sup {minus}}, {ital K}{sup +}{ital K}{sup {minus}}, 2({pi}{sup +}{pi}{sup {minus}}), etc., are taken on the resonances {eta}{sub {ital c}} and {chi}{sub {ital c}0}, respectively. The relatively large {eta}{sub {ital c}} and {chi}{sub {ital c}0} decay widths, of about 10--15 MeV, provide the necessary absorptive phase in the interference between the resonance (going through {ital b}{r_arrow}{ital c{bar c}d}) and the background (through {ital b}{r_arrow}{ital u{bar u}d}) contributions to the amplitude. Large asymmetries of order 10% or more are likely in some modes.

  9. Signal Processing, Analysis, & Display

    SciTech Connect

    Lager, Darrell; Azevado, Stephen

    1986-06-01

    SIG is a general-purpose signal processing, analysis, and display program. Its main purpose is to perform manipulations on time- and frequency-domain signals. However, it has been designed to ultimately accommodate other representations for data such as multiplexed signals and complex matrices. Two user interfaces are provided in SIG - a menu mode for the unfamiliar user and a command mode for more experienced users. In both modes errors are detected as early as possible and are indicated by friendly, meaningful messages. An on-line HELP package is also included. A variety of operations can be performed on time- and frequency-domain signals including operations on the samples of a signal, operations on the entire signal, and operations on two or more signals. Signal processing operations that can be performed are digital filtering (median, Bessel, Butterworth, and Chebychev), ensemble average, resample, auto and cross spectral density, transfer function and impulse response, trend removal, convolution, Fourier transform and inverse window functions (Hamming, Kaiser-Bessel), simulation (ramp, sine, pulsetrain, random), and read/write signals. User definable signal processing algorithms are also featured. SIG has many options including multiple commands per line, command files with arguments,commenting lines, defining commands, and automatic execution for each item in a repeat sequence. Graphical operations on signals and spectra include: x-y plots of time signals; real, imaginary, magnitude, and phase plots of spectra; scaling of spectra for continuous or discrete domain; cursor zoom; families of curves; and multiple viewports.

  10. Lift, Drag, and Pitching Moments of an Arrow Wing Having 80 Degree of Sweepback at Mach Numbers from 2.48 to 3.51 and Reynolds Numbers up to 11.0 Million

    NASA Technical Reports Server (NTRS)

    Hopkins, Edward J.; Jillie, Don W.; Levin, Alan D.

    1959-01-01

    Measurements were made of the lift, drag, and pitching moments on an arrow wing (taper ratio of zero) having an aspect ratio of 1.4 and a leading-edge sweepback of 80 (degrees). The wing was designed to have a subsonic leading-edge and a Clark-Y airfoil with a thickness ratio of 12 percent of the chord perpendicular to the wing leading edge. The wing was tested both with and without the wing tips bent upward in an attempt to alleviate possible flow separation in the vicinity of the wing tips. Small jets of air were used to fix transition near the wing leading edge. Force results are presented for Mach numbers of 2.48, 2.75, 3.04, 3.28, and 3.51 at Reynolds numbers of 3.5 and 9.0 million and for a Mach number of 3.04 at a Reynolds number of 11.0 million. The measured aerodynamic characteristics are compared with those estimated by linear theory. The maximum lift-drag ratio measured was much less than that predicted. This difference is attributed to lack of full leading-edge thrust and to the experimental lift-curve slope being about 20 percent below the theoretical value.