Sample records for arrows signals

  1. On the time arrows, and randomness in cosmological signals

    NASA Astrophysics Data System (ADS)

    Gurzadyan, V. G.; Sargsyan, S.; Yegorian, G.

    2013-09-01

    Arrows of time - thermodynamical, cosmological, electromagnetic, quantum mechanical, psychological - are basic properties of Nature. For a quantum system-bath closed system the de-correlated initial conditions and no-memory (Markovian) dynamics are outlined as necessary conditions for the appearance of the thermodynamical arrow. The emergence of the arrow for the system evolving according to non-unitary dynamics due to the presence of the bath, then, is a result of limited observability, and we conjecture the arrow in the observable Universe as determined by the dark sector acting as a bath. The voids in the large scale matter distribution induce hyperbolicity of the null geodesics, with possible observational consequences.

  2. 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. Copyright © 2014. Published by Elsevier Ltd.

  3. 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.

  4. Improved pedestrian safety at signalized intersections operating the flashing yellow arrow.

    DOT National Transportation Integrated Search

    2013-04-01

    In some jurisdictions, protected left-turn phasing has been replaced with the flashing yellow arrow (FYA) for : protected/permissive left turns (PPLTs) to reduce delay. However, it is important to have a thorough understanding of the : conflict betwe...

  5. 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…

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

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

    David Atwood; Marc Sher

    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 +more » 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.« less

  7. 77 FR 35082 - Arrow Investment Advisers, LLC and Arrow Investments Trust; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... SECURITIES AND EXCHANGE COMMISSION [Investment Company Act Release No. 30100; 812-13937] Arrow Investment Advisers, LLC and Arrow Investments Trust; Notice of Application June 6, 2012. AGENCY: Securities... 6(c) of the Investment Company Act of 1940 (``Act'') for an exemption from sections 2(a)(32), 5(a)(1...

  8. Environmental and Molecular Science Laboratory Arrow

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

    2016-06-24

    Arrows is a software package that combines NWChem, SQL and NOSQL databases, email, and social networks (e.g. Twitter, Tumblr) that simplifies molecular and materials modeling and makes these modeling capabilities accessible to all scientists and engineers. EMSL Arrows is very simple to use. The user just emails chemical reactions to arrows@emsl.pnnl.gov and then an email is sent back with thermodynamic, reaction pathway (kinetic), spectroscopy, and other results. EMSL Arrows parses the email and then searches the database for the compounds in the reactions. If a compound isn't there, an NWChem calculation is setup and submitted to calculate it. Once themore » calculation is finished the results are entered into the database and then results are emailed back.« less

  9. Does a Computer Have an Arrow of Time?

    NASA Astrophysics Data System (ADS)

    Maroney, Owen J. E.

    2010-02-01

    Schulman (Entropy 7(4):221-233, 2005) has argued that Boltzmann’s intuition, that the psychological arrow of time is necessarily aligned with the thermodynamic arrow, is correct. Schulman gives an explicit physical mechanism for this connection, based on the brain being representable as a computer, together with certain thermodynamic properties of computational processes. Hawking (Physical Origins of Time Asymmetry, Cambridge University Press, Cambridge, 1994) presents similar, if briefer, arguments. The purpose of this paper is to critically examine the support for the link between thermodynamics and an arrow of time for computers. The principal arguments put forward by Schulman and Hawking will be shown to fail. It will be shown that any computational process that can take place in an entropy increasing universe, can equally take place in an entropy decreasing universe. This conclusion does not automatically imply a psychological arrow can run counter to the thermodynamic arrow. Some alternative possible explanations for the alignment of the two arrows will be briefly discussed.

  10. Quantum voting and violation of Arrow's impossibility theorem

    NASA Astrophysics Data System (ADS)

    Bao, Ning; Yunger Halpern, Nicole

    2017-06-01

    We propose a quantum voting system in the spirit of quantum games such as the quantum prisoner's dilemma. Our scheme enables a constitution to violate a quantum analog of Arrow's impossibility theorem. Arrow's theorem is a claim proved deductively in economics: Every (classical) constitution endowed with three innocuous-seeming properties is a dictatorship. We construct quantum analogs of constitutions, of the properties, and of Arrow's theorem. A quantum version of majority rule, we show, violates this quantum Arrow conjecture. Our voting system allows for tactical-voting strategies reliant on entanglement, interference, and superpositions. This contribution to quantum game theory helps elucidate how quantum phenomena can be harnessed for strategic advantage.

  11. Penetrating injury of ascending aorta with arrow in situ.

    PubMed

    Lakhotia, Siddharth; Prakash, Shashi; Singh, Dinesh Kumar; Kumar, Ashok; Panigrahi, Debasish

    2012-04-01

    Penetrating injuries of the aorta are rare and highly lethal; very few patients are able to reach the hospital alive. We report a case of penetrating injury into the ascending aorta with the arrow still in situ, shot by a bow in a tribal region of India. The wound of entry into the aorta was sealed by the arrow itself. The patient came to us walking and supporting the arrow with his left hand. He was operated on, and the arrow was successfully removed from the aorta. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  12. 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,…

  13. The Effect of Arrow Mass and Shape on Penetration into a Target

    NASA Astrophysics Data System (ADS)

    Shyam, S.; Gurram, A.; Madireddy, S.

    2016-12-01

    We conducted an archery experiment in order to quantify how aerodynamic design impacted the depth of arrow impact. Research shows that the smaller the surface area of an object, the more easily it travels through the air and the deeper it penetrates a target (Benson 2014). Momentum also affects how far and fast the arrow will go and therefore, how deep it will penetrate into the target. Therefore, a combination of an arrow with greater momentum and better aerodynamics will help the arrow fly faster and penetrate the target deeper. Mass, velocity, momentum, acceleration, force, and drag are the factors that acted on our experiment and produced its results. We hypothesized that the arrow with a thin shaft and pointed arrowhead would penetrate deepest, as opposed to both arrows with no arrowheads or arrows with thick shafts and blunt arrowheads. We tested our hypothesis by having a well-trained archer shoot different types of arrows into a target. We used arrows with shaft lengths of 7 cm and 5.3 cm, coupled with either pointed, blunt, or no arrowhead. We measured the time to target and arrow penetration (in cm) to see which style reached the target the fastest and penetrated the deepest. The results demonstrated that arrows with thin shafts and pointed arrowheads penetrated our target the deepest, followed by arrows with thick shafts and blunt arrowheads. Arrows with thin shafts and blunt arrowheads came after, and arrows with thick shafts and pointed arrowheads came last in depth of penetration. The arrows with no arrowheads either barely penetrated the target, or bounced back. We were able to conclude that the thinner the shaft and the more pointed the arrowhead, the better the arrow cuts the air. This is because, according to the principles of aerodynamics, it creates less drag since the surface area is smaller. However, mass also plays an important role in force through momentum, which also significantly affected our results.

  14. Indeterminacy of drag exerted on an arrow in free flight: arrow attitude and laminar-turbulent transition

    NASA Astrophysics Data System (ADS)

    Miyazaki, T.; Matsumoto, T.; Ando, R.; Ortiz, J.; Sugiura, H.

    2017-11-01

    The aerodynamic properties of an arrow (A/C/E; Easton) were investigated in an extension of our previous work, in which the laminar-turbulent transition of the boundary layer on the arrow shaft was found to take place in the Re number range of 1.2 × 104 < Re < 2.0 × 104. In this paper, we focus on the influence of the arrow’s attitude on the transition. Two types of vane (Spin Wing vane and Gas Pro vane) are fletched, and their stabilizing effects are compared. Two support-interference-free tests are performed to provide aerodynamic properties such as the drag, lift and pitching moment coefficients. The static aerodynamic properties are measured in a wind tunnel with JAXA’s 60 cm magnetic suspension and balance system. When the arrow is aligned with the flow, the boundary layer remains laminar for Re < 1.5 × 104, and the drag coefficient is approximately 1.5 for 1.0 × 104 < Re < 1.5 × 104. If the arrow has an angle of attack of 0.75 ° with the flow, the transition to turbulence takes place at approximately Re = 1.1 × 104, and the drag coefficient increases to approximately 3.1. In addition, free flight experiments are performed. The arrow’s velocity and angular velocity are recorded using five high-speed video cameras. By analysing the recorded images, we obtain the initial and final velocities from which the drag coefficient is determined. The trajectory and attitude of the arrow in free flight are computed numerically by integrating the equations of motion for a rigid body using the initial data obtained from the video images. The laminar-turbulent transition of the boundary layer is shown to take place, if the maximum angle of attack exceeds about 0.4° at Re = 1.75 × 104. The crucial influence of the initial angular velocity on the angle of attack is also examined.

  15. Conflict Tasks of Different Types Divergently Affect the Attentional Processing of Gaze and Arrow.

    PubMed

    Fan, Lingxia; Yu, Huan; Zhang, Xuemin; Feng, Qing; Sun, Mengdan; Xu, Mengsi

    2018-01-01

    The present study explored the attentional processing mechanisms of gaze and arrow cues in two different types of conflict tasks. In Experiment 1, participants performed a flanker task in which gaze and arrow cues were presented as central targets or bilateral distractors. The congruency between the direction of the target and the distractors was manipulated. Results showed that arrow distractors greatly interfered with the attentional processing of gaze, while the processing of arrow direction was immune to conflict from gaze distractors. Using a spatial compatibility task, Experiment 2 explored the conflict effects exerted on gaze and arrow processing by their relative spatial locations. When the direction of the arrow was in conflict with its spatial layout on screen, response times were slowed; however, the encoding of gaze was unaffected by spatial location. In general, processing to an arrow cue is less influenced by bilateral gaze cues but is affected by irrelevant spatial information, while processing to a gaze cue is greatly disturbed by bilateral arrows but is unaffected by irrelevant spatial information. Different effects on gaze and arrow cues by different types of conflicts may reflect two relatively distinct specific modes of the attentional process.

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

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

    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)more » 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

  17. 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.

  18. Geophysical Interpretation of Induction Arrows Observed at Jeju Island, Korea

    NASA Astrophysics Data System (ADS)

    Yang, J.; Choi, H.

    2015-12-01

    Jeju Island, a volcanic island located on the continental margin in the southern end of the Korean Peninsula, has been paid a special attention to geological and geophysical society for a long time due to its tectonic importance associated with the volcanism of the island. In this study, we try to interpret induction arrows observed at the island that have been estimated from broad-band magnetotelluric (MT) data and existing magnetovariational data, which are sensitive to lateral conductivity distribution of the Earth. Overall pattern of observed induction arrows is clearly frequency-dependent: perpendicular to nearby coastline of the observation site for higher frequencies than 0.1 Hz but rotating toward south or southeastern direction for lower frequency than 0.01 Hz. Furthermore, induction arrows at frequencies lower than 0.001 Hz, which derived from the existing magnetovariational data, point to the south or the southeast as well. In order to examine whether observed induction arrows can be explained by only surrounding seas, 3-D MT modeling considering seas surrounding the island is carried out. The results demonstrate that induction arrows at higher frequencies than 0.01 Hz can be explained well by the surrounding seas but for lower frequencies than 0.01 Hz there are significant discrepancies between observed and calculated arrows. This strongly implies the existence of deep-seated conductor located beneath the farther south of the island, namely, the East China Sea. The existence of this deep-seated conductor can be supported by other previous geophysical studies, which is likely to be caused by mantle upwelling derived from shear traction of horizontal mantle flow in tensional back arc of Kyushu Island, Japan.

  19. Measuring effects of voluntary attention: a comparison among predictive arrow, colour, and number cues.

    PubMed

    Olk, Bettina; Tsankova, Elena; Petca, A Raisa; Wilhelm, Adalbert F X

    2014-10-01

    The Posner cueing paradigm is one of the most widely used paradigms in attention research. Importantly, when employing it, it is critical to understand which type of orienting a cue triggers. It has been suggested that large effects elicited by predictive arrow cues reflect an interaction of involuntary and voluntary orienting. This conclusion is based on comparisons of cueing effects of predictive arrows, nonpredictive arrows (involuntary orienting), and predictive numbers (voluntary orienting). Experiment 1 investigated whether this conclusion is restricted to comparisons with number cues and showed similar results to those of previous studies, but now for comparisons to predictive colour cues, indicating that the earlier conclusion can be generalized. Experiment 2 assessed whether the size of a cueing effect is related to the ease of deriving direction information from a cue, based on the rationale that effects for arrows may be larger, because it may be easier to process direction information given by symbols such as arrows than that given by other cues. Indeed, direction information is derived faster and more accurately from arrows than from colour and number cues in a direction judgement task, and cueing effects are larger for arrows than for the other cues. Importantly though, performance in the two tasks is not correlated. Hence, the large cueing effects of arrows are not a result of the ease of information processing, but of the types of orienting that the arrows elicit.

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

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

    Schindler, E.

    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 previousmore » 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

  1. 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.

  2. The location-, word-, and arrow-based Simon effects: An ex-Gaussian analysis.

    PubMed

    Luo, Chunming; Proctor, Robert W

    2018-04-01

    Task-irrelevant spatial information, conveyed by stimulus location, location word, or arrow direction, can influence the response to task-relevant attributes, generating the location-, word-, and arrow-based Simon effects. We examined whether different mechanisms are involved in the generation of these Simon effects by fitting a mathematical ex-Gaussian function to empirical response time (RT) distributions. Specifically, we tested whether which ex-Gaussian parameters (μ, σ, and τ) show Simon effects and whether the location-, word, and arrow-based effects are on different parameters. Results show that the location-based Simon effect occurred on mean RT and μ but not on τ, and a reverse Simon effect occurred on σ. In contrast, a positive word-based Simon effect was obtained on all these measures (including σ), and a positive arrow-based Simon effect was evident on mean RT, σ, and τ but not μ. The arrow-based Simon effect was not different from the word-based Simon effect on τ or σ but was on μ and mean RT. These distinct results on mean RT and ex-Gaussian parameters provide evidence that spatial information conveyed by the various location modes are different in the time-course of activation.

  3. Cupid's Arrow: An Innovative Nanosat to Sample Venus' Upper Atmosphere

    NASA Technical Reports Server (NTRS)

    Bienstock, Bernie; Darrach, Murray; Madzunkov, Stojan; Sotin, Christophe

    2016-01-01

    In NASA's Discovery 2014 AO, the opportunity to propose a Technology Demonstration Opportunity (TDO) to enhance the primary mission was specified. For the Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS) mission, we elected to include the Cupid's Arrow nanosat TDO to sample and measure the abundances of noble gases and their isotopic ratios in Venus's upper atmosphere below the homopause. This paper will provide a basic overview of the VERITAS mission, with a focus on the Cupid's Arrow concept including a description of the mission, spacecraft design, and JPL's quadrupole ion trap mass spectrometer (QITMS) instrument specifications and design. In previous planetary entry probe mission designs, particularly at Venus, engineers w ere focused on entry and descent. A landed probe was also proposed for the New Frontiers SAGE mission. For Cupid's Arrow, the nanosat is designed to skim through the upper atmosphere, just below the homopause, in order to sample the atmosphere, perform the analysis, and then exit the atmosphere to transmit its data to the orbiting VERITAS spacecraft. Cupid's Arrow is a compelling addition to the VERITAS geology mission. A key missing link in our understanding of Venus' evolution is the noble gas abundances and their isotopic ratios. Not since Pioneer Venus have these measurements been made in the Venus atmosphere and never in the upper atmosphere, just below the homopause, to the degree of accuracy that will be accomplished by VERITAS' Cupid's Arrow nanosat.Such measurements were ranked as the number 1 investigation of the number 1 objective of the goal "Atmospheric Formation, Evolution, and Climate History ".

  4. Dynamic flashing yellow arrow (FYA): a study on variable left-turn mode operational and safety impacts phase II - model expansion and testing.

    DOT National Transportation Integrated Search

    2016-06-01

    The flashing yellow arrow (FYA) signal display creates an opportunity to enhance the left-turn phase with a : variable mode that can be changed on demand. The previously developed decision support system (DSS) in : phase I facilitated the selection o...

  5. 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.…

  6. The Invincible Bomber-In Search of Loki’s Arrow

    DTIC Science & Technology

    2015-06-01

    MAXWELL AIR FORCE BASE, ALABAMA JUNE 2015 DISTRIBUTION A. Approved for public release: distribution unlimited. APPROVAL The undersigned...69 1 Chapter 1 Introduction I think it is well also for the man in the street to realize that there is no power on earth that can...Baldr’s brother Hod to shoot at Baldr for fun . When Hod shot Baldr with the mistletoe arrow, the arrow instantly killed Baldr. Loki faded from sight

  7. 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.

  8. Maxwell's demons everywhere: evolving design as the arrow of time.

    PubMed

    Bejan, Adrian

    2014-02-10

    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.

  9. Reverse Engineering a Signaling Network Using Alternative Inputs

    PubMed Central

    Tanaka, Hiromasa; Yi, Tau-Mu

    2009-01-01

    One of the goals of systems biology is to reverse engineer in a comprehensive fashion the arrow diagrams of signal transduction systems. An important tool for ordering pathway components is genetic epistasis analysis, and here we present a strategy termed Alternative Inputs (AIs) to perform systematic epistasis analysis. An alternative input is defined as any genetic manipulation that can activate the signaling pathway instead of the natural input. We introduced the concept of an “AIs-Deletions matrix” that summarizes the outputs of all combinations of alternative inputs and deletions. We developed the theory and algorithms to construct a pairwise relationship graph from the AIs-Deletions matrix capturing both functional ordering (upstream, downstream) and logical relationships (AND, OR), and then interpreting these relationships into a standard arrow diagram. As a proof-of-principle, we applied this methodology to a subset of genes involved in yeast mating signaling. This experimental pilot study highlights the robustness of the approach and important technical challenges. In summary, this research formalizes and extends classical epistasis analysis from linear pathways to more complex networks, facilitating computational analysis and reconstruction of signaling arrow diagrams. PMID:19898612

  10. Electron-impact excitation of the 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P} and 1{sup 1}{ital S}{r_arrow}4{sup 1}{ital P} transitions in helium

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

    Khakoo, M.A.; Roundy, D.; Rugamas, F.

    1996-11-01

    The method of electron-photon coincidence is used to {open_quote}{open_quote}resolve{close_quote}{close_quote} the electron-impact excitation of the {ital n}{sup 1}{ital P} levels ({ital n}=3 and 4) from nearby levels. Experimentally determined ratios of the differential cross sections for the electron-impact excitation of 1{sup 1}{ital S}{r_arrow}2{sup 1}{ital P}, to 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P}, and 4{sup 1}{ital P} transitions are presented at 30-, 40-, and 80-eV incident electron energies. Differential cross sections for the 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P} and 1{sup 1}{ital S}{r_arrow}4{sup 1}{ital P} transitions are derived by normalizing these ratios to available experimental differential cross sections for the 1{sup 1}{ital S}{r_arrow}2{sup 1}{italmore » P} transition. The ratios and differential cross sections are compared to available theoretical and semiempirical data. {copyright} {ital 1996 The American Physical Society.}« less

  11. 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

  12. Single mode, broad-waveguide ARROW-type semiconductor diode lasers

    NASA Astrophysics Data System (ADS)

    Al-Muhanna, Abdulrahman Ali

    A broad transverse waveguide (low confinement) concept is used to achieve a record-high spatially incoherent cw output power of 11W for InGaAs active devices (λ = 0.97 μm) from 100μm wide-stripe and 2mm-long devices with low internal loss, α1 = 1cm-1, and high characteristic temperatures, T0 = 210K, and T1 = 1800K. A detailed above-threshold analysis reveals that reduction in gain spatial hole burning (GSHB) is possible in ARROW-type structures by using a low transverse confinement factor; consequently, a wider ARROW-core can be utilized. By incorporating both a broad-waveguide concept as well as an asymmetric structure in the transverse direction, and an ARROW-type structure in the lateral direction, a novel single-spatial mode diode laser with improved performance is obtained. Devices with low transverse confinement factor (Γ ~ 1%) and a core-region width of 7.8 μm achieved 510mW single-spatial mode pulsed output power (λ = 0.946 μm) with a full- width at half-maximum (FWHM) of the lateral far-field pattern of 4.7°.

  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. Arrows in Biology: Lack of Clarity and Consistency Points to Confusion for Learners

    ERIC Educational Resources Information Center

    Wright, L. Kate; Cardenas, Jordan J.; Liang, Phyllis; Newman, Dina L.

    2018-01-01

    In this article, we begin to unpack the phenomenon of representational competence by exploring how arrow symbols are used in introductory biology textbook figures. Out of 1214 figures in an introductory biology textbook, 632 (52%) of them contained arrows that were used to represent many different concepts or processes. Analysis of these figures…

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Sociopolitical effects of bow and arrow technology in prehistoric coastal California.

    PubMed

    Kennett, Douglas J; Lambert, Patricia M; Johnson, John R; Culleton, Brendan J

    2013-01-01

    Bow and arrow technology spread across California between ∼AD 250 and 1200, first appearing in the intermountain deserts of the Great Basin and later spreading to the coast. We critically evaluate the available data for the initial spread in bow and arrow technology and examine its societal effects on the well-studied Northern Channel Islands off the coast of Southern California. The introduction of this technology to these islands between AD 650 and 900 appears to predate the appearance of hereditary inequality between AD 900 and 1300. We conclude, based on the available data, that this technology did not immediately trigger intergroup warfare. We argue that the introduction of the bow and arrow contributed to sociopolitical instabilities that were on the rise within the context of increasing population levels and unstable climatic conditions, which stimulated intergroup conflict and favored the development of hereditary inequality. Population aggregation and economic intensification did occur with the introduction of the bow and arrow. This observation is consistent with the hypothesis that social coercion via intra-group "law enforcement" contributed to changes in societal scale that ultimately resulted in larger groups that were favored in inter-group conflict. We argue that the interplay between intra-group "law enforcement" and inter-group warfare were both essential for the ultimate emergence of social inequality between AD 900 and 1300. Copyright © 2013 Wiley Periodicals, Inc.

  17. Pycellerator: an arrow-based reaction-like modelling language for biological simulations.

    PubMed

    Shapiro, Bruce E; Mjolsness, Eric

    2016-02-15

    We introduce Pycellerator, a Python library for reading Cellerator arrow notation from standard text files, conversion to differential equations, generating stand-alone Python solvers, and optionally running and plotting the solutions. All of the original Cellerator arrows, which represent reactions ranging from mass action, Michales-Menten-Henri (MMH) and Gene-Regulation (GRN) to Monod-Wyman-Changeaux (MWC), user defined reactions and enzymatic expansions (KMech), were previously represented with the Mathematica extended character set. These are now typed as reaction-like commands in ASCII text files that are read by Pycellerator, which includes a Python command line interface (CLI), a Python application programming interface (API) and an iPython notebook interface. Cellerator reaction arrows are now input in text files. The arrows are parsed by Pycellerator and translated into differential equations in Python, and Python code is automatically generated to solve the system. Time courses are produced by executing the auto-generated Python code. Users have full freedom to modify the solver and utilize the complete set of standard Python tools. The new libraries are completely independent of the old Cellerator software and do not require Mathematica. All software is available (GPL) from the github repository at https://github.com/biomathman/pycellerator/releases. Details, including installation instructions and a glossary of acronyms and terms, are given in the Supplementary information. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. A Driving Simulator Evaluation of Red Arrows and Flashing Yellow Arrows in Right-Turn Applications : Establishing the Foundation for Future Research

    DOT National Transportation Integrated Search

    2017-11-01

    Driver understanding of flashing yellow arrow (FYA) indications for left turns has been studied extensively; however, the use of FYA for right-turn applications is an area that needs to be better understood through evaluations focused on actual drive...

  19. Tragic Paradox in Achebe's "Arrow of God"

    ERIC Educational Resources Information Center

    Soile, Sola

    1976-01-01

    Leads into a discussion of Chinua Achebe's "Arrow of God" (1964) from his earlier novel "Things Fall Apart" (1958), because such a comparative approach provides an opportunity to see Achebe's elaboration and development of a subject that is obviously dear to his heart, namely, the trials and tribulations of a dynamic society as…

  20. 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.

  1. 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,…

  2. Synthetic Minor NSR Permit: Arrow Pipeline, LLC - Station #7

    EPA Pesticide Factsheets

    This page contains the administratively revised synthetic minor permit to construct for the Arrow Pipeline, LLC, Station #7, located within the exterior boundaries of the Fort Berthold Indian Reservation in Dunn County, North Dakota.

  3. Iroquois Engine for the Avro Arrow in the Propulsion Systems Laboratory

    NASA Image and Video Library

    1957-08-21

    A researcher examines the Orenda Iroquois PS.13 turbojet in a Propulsion Systems Laboratory test chamber at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. The Iroquois was being developed to power the CF-105 Arrow fighter designed by the Avro Canada Company. Avro began design work on the Arrow jet fighter in 1952. The company’s Orenda branch suggested building a titanium-based PS.13 Iroquois engine after development problems arose with the British engines that Avro had originally intended to use. The 10-stage, 20,000-pound-thrust Iroquois would prove to be more powerful than any contemporary US or British turbojet. It was also significantly lighter and more fuel efficient. An Iroquois was sent to Cleveland in April 1957 so that Lewis researchers could study the engine’s basic performance for the air force in the Propulsion Systems Laboratory. The tests were run over a wide range of speeds and altitudes with variations in exhaust-nozzle area. Initial studies determined the Iroquois’s windmilling and ignition characteristics at high altitude. After operating for 64 minutes, the engine was reignited at altitudes up to the 63,000-foot limit of the facility. Various modifications were attempted to reduce the occurrence of stall but did not totally eradicate the problem. The Arrow jet fighter made its initial flight in March 1958 powered by a substitute engine. In February 1959, however, both the engine and the aircraft programs were cancelled. The world’s superpowers had quickly transitioned from bombers to ballistic missiles which rendered the Avro Arrow prematurely obsolete.

  4. Driver comprehension and operations evaluation of flashing yellow arrows.

    DOT National Transportation Integrated Search

    2013-06-01

    In spring 2010, the Illinois Department of Transportation initiated an areawide implementation of the flashing yellow : arrow (FYA) as the display for the left-turn permissive interval at more than 100 intersections operating with : protected/permiss...

  5. Time's arrow: A numerical experiment

    NASA Astrophysics Data System (ADS)

    Fowles, G. Richard

    1994-04-01

    The dependence of time's arrow on initial conditions is illustrated by a numerical example in which plane waves produced by an initial pressure pulse are followed as they are multiply reflected at internal interfaces of a layered medium. Wave interactions at interfaces are shown to be analogous to the retarded and advanced waves of point sources. The model is linear and the calculation is exact and demonstrably time reversible; nevertheless the results show most of the features expected of a macroscopically irreversible system, including the approach to the Maxwell-Boltzmann distribution, ergodicity, and concomitant entropy increase.

  6. 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

  7. Recent developments in the field of arrow and dart poisons.

    PubMed

    Philippe, Geneviève; Angenot, Luc

    2005-08-22

    Arrow and dart poisons, considered as conventional natural sources for future drug discovery, have already provided numerous biologically active molecules used as drugs in therapeutic applications or in pharmacological research. Plants containing alkaloids or cardiotonic glycosides have generally been the main ingredients responsible for the efficacy of these poisons, although some animals, such as frogs, have also been employed. This paper, without being exhaustive, reports the greater strides made during the past 15 years in the understanding of the chemical nature and biological properties of arrow and dart poison constituents. Examples both of promising biological properties shown by these molecules and of crucial discoveries achieved by their use as pharmacological tools are given. Further studies of these toxic principles are likely to enable scientists to find new valuable lead compounds, useful in many fields of research, like oncology, inflammation and infectious diseases.

  8. Electron impact excitation of the 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P} transition in helium

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

    Khakoo, M.A.; Roundy, D.; Rugamas, F.

    1995-07-03

    In the first direct application of the electron-photon coincidence technique for differential cross-section measurements, experimentally determined ratios of the differential cross sections for the electron impact excitation of the 1{sup 1}{ital S}{r_arrow}2{sup 1}{ital P} to the 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P} transitions are presented at 30 and 40 eV incident electron energies. Differential cross sections for the 1{sup 1}{ital S}{r_arrow}3{sup 1}{ital P} transitions are derived by normalizing these ratios to available experimental differential cross sections for the 1{sup 1}{ital S}{r_arrow}2{sup 1}{ital P} transition.

  9. Recognition of Damaged Arrow-Road Markings by Visible Light Camera Sensor Based on Convolutional Neural Network.

    PubMed

    Vokhidov, Husan; Hong, Hyung Gil; Kang, Jin Kyu; Hoang, Toan Minh; Park, Kang Ryoung

    2016-12-16

    Automobile driver information as displayed on marked road signs indicates the state of the road, traffic conditions, proximity to schools, etc. These signs are important to insure the safety of the driver and pedestrians. They are also important input to the automated advanced driver assistance system (ADAS), installed in many automobiles. Over time, the arrow-road markings may be eroded or otherwise damaged by automobile contact, making it difficult for the driver to correctly identify the marking. Failure to properly identify an arrow-road marker creates a dangerous situation that may result in traffic accidents or pedestrian injury. Very little research exists that studies the problem of automated identification of damaged arrow-road marking painted on the road. In this study, we propose a method that uses a convolutional neural network (CNN) to recognize six types of arrow-road markings, possibly damaged, by visible light camera sensor. Experimental results with six databases of Road marking dataset, KITTI dataset, Málaga dataset 2009, Málaga urban dataset, Naver street view dataset, and Road/Lane detection evaluation 2013 dataset, show that our method outperforms conventional methods.

  10. Recognition of Damaged Arrow-Road Markings by Visible Light Camera Sensor Based on Convolutional Neural Network

    PubMed Central

    Vokhidov, Husan; Hong, Hyung Gil; Kang, Jin Kyu; Hoang, Toan Minh; Park, Kang Ryoung

    2016-01-01

    Automobile driver information as displayed on marked road signs indicates the state of the road, traffic conditions, proximity to schools, etc. These signs are important to insure the safety of the driver and pedestrians. They are also important input to the automated advanced driver assistance system (ADAS), installed in many automobiles. Over time, the arrow-road markings may be eroded or otherwise damaged by automobile contact, making it difficult for the driver to correctly identify the marking. Failure to properly identify an arrow-road marker creates a dangerous situation that may result in traffic accidents or pedestrian injury. Very little research exists that studies the problem of automated identification of damaged arrow-road marking painted on the road. In this study, we propose a method that uses a convolutional neural network (CNN) to recognize six types of arrow-road markings, possibly damaged, by visible light camera sensor. Experimental results with six databases of Road marking dataset, KITTI dataset, Málaga dataset 2009, Málaga urban dataset, Naver street view dataset, and Road/Lane detection evaluation 2013 dataset, show that our method outperforms conventional methods. PMID:27999301

  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. Evaluation of arrow panel displays for temporary work zones : final report.

    DOT National Transportation Integrated Search

    2001-08-01

    The Oregon Department of Transportation evaluated the effectiveness of a sequentially flashing diamond arrow panel display as advance caution warning in temporary work zones. This display was evaluated by comparing it with two others; the flash...

  13. 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.

  14. 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.

  15. Ichthyosporidium weissii n. sp. (Microsporidia) Infecting the Arrow Goby (Clevelandia ios)

    PubMed Central

    SANDERS, JUSTIN; MYERS, MARK S.; TOMANEK, LARS; CALI, ANN; TAKVORIAN, PETER M.; KENT, MICHAEL L.

    2012-01-01

    Gonadal infections by a novel microsporidium were discovered in 34% (13/38) of arrow gobies, Clevelandia ios, sampled over a three year period from Morro Bay Marina in Morro Bay, California. Gonadal tumors had been reported in arrow gobies from this geographic area. The infected gonads, found primarily in females, typically appeared grossly as large, white-gray firm and lobulated masses. Histological examination revealed large, multilobate xenomas within the ovaries and no evidence of neoplasia. Typical of the genus Ichthyosporidium, the large xenomas were filled with developmental stages and pleomorphic spores. Wet mount preparations showed two general spore types: microspores with mean length of 6.2 (7.0–4.9, SD = 0.6, N = 20) μm and mean width of 4.3 (5.3–2.9, SD = 0.8) μm; and less numerous macrospores with mean length of 8.5 (10.1–7.1, SD = 1.0, N = 10) μm and mean width of 5.5 (6.2–4.8, SD = 0.5) μm. Transmission electron microscopy demonstrated stages consistent with the genus and 35–50 turns of the polar filament. Small subunit (SSU) rDNA gene sequence analysis revealed that the parasite from arrow gobies was most closely related to, but distinct from Ichthyosporidium sp. based on sequences available in GenBank. We conclude that this microsporidium represents a new species of Ichthyosporidium, the first species of this genus described from a member of the family Gobiidae and from the Pacific Ocean. PMID:22486936

  16. Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias.

    PubMed

    Laycock, Robin; Chan, Daniel; Crewther, Sheila G

    2017-01-01

    One aspect of the social communication impairments that characterize autism spectrum disorder (ASD) include reduced use of often subtle non-verbal social cues. People with ASD, and those with self-reported sub-threshold autistic traits, also show impairments in rapid visual processing of stimuli unrelated to social or emotional properties. Hence, this study sought to investigate whether perceptually non-conscious visual processing is related to autistic traits. A neurotypical sample of thirty young adults completed the Subthreshold Autism Trait Questionnaire and a Posner-like attention cueing task. Continuous Flash Suppression (CFS) was employed to render incongruous hierarchical arrow cues perceptually invisible prior to consciously presented targets. This was achieved via a 10 Hz masking stimulus presented to the dominant eye that suppressed information presented to the non-dominant eye. Non-conscious arrows consisted of local arrow elements pointing in one direction, and forming a global arrow shape pointing in the opposite direction. On each trial, the cue provided either a valid or invalid cue for the spatial location of the subsequent target, depending on which level (global or local) received privileged attention. A significant autism-trait group by global cue validity interaction indicated a difference in the extent of non-conscious local/global cueing between groups. Simple effect analyses revealed that whilst participants with lower autistic traits showed a global arrow cueing effect, those with higher autistic traits demonstrated a small local arrow cueing effect. These results suggest that non-conscious processing biases in local/global attention may be related to individual differences in autistic traits.

  17. Some applications of the NASTRAN level 16 subsonic flutter analysis capability. [to transport wing and arrow wing

    NASA Technical Reports Server (NTRS)

    Doggett, R. V., Jr.; Cunningham, H. J.

    1976-01-01

    The Level 16 flutter analysis capability was applied to an aspect-ratio-6.8 subsonic transport type wing, an aspect-ratio-1.7 arrow wing, and an aspect-ratio-1.3 all movable horizontal tail with a geared elevator. The transport wing and arrow wing results are compared with experimental results obtained in the Langley transonic dynamic tunnel and with other calculated results obtained using subsonic lifting surface (kernel function) unsteady aerodynamic theory.

  18. Use of Flashing Yellow Operations to Improve Safety at Signals with Protected-Permissive Left Turn (PPLT) Operations

    DOT National Transportation Integrated Search

    2012-10-01

    MUTCD 2009 Edition suggests the use of Flashing Yellow Arrow (FYA) indication in replacement of green ball indication for permissive left-turn signal in presence of separate signal heads. Currently, there is no clear guidance on how to implement flas...

  19. Use of flashing yellow operations to improve safety at signals with protected-permissive left turn (PPLT) operations

    DOT National Transportation Integrated Search

    2012-10-01

    MUTCD 2009 Edition suggests the use of Flashing Yellow Arrow (FYA) indication in replacement of green ball indication for permissive left-turn signal in presence of separate signal heads. Currently, there is no clear guidance on how to implement flas...

  20. 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

  1. Investigating Hemispheric Lateralization of Reflexive Attention to Gaze and Arrow Cues

    ERIC Educational Resources Information Center

    Marotta, Andrea; Lupianez, Juan; Casagrande, Maria

    2012-01-01

    Recent studies have demonstrated that central cues, such as eyes and arrows, reflexively trigger attentional shifts. However, it is not clear whether the attentional mechanisms induced by these two cues are similar or rather differ in some important way. We investigated hemispheric lateralization of the orienting effects induced by the two cue…

  2. 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.

  3. 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…

  4. Use of Flashing Yellow Operations to Improve Safety at Signals with Protected-Permissive Left Turn (PPLT)Operations : Project Summary

    DOT National Transportation Integrated Search

    2011-08-31

    The 2009 edition of the federal MUTCD suggests the use of the flashing yellow arrow (FYA) indication in lieu : of the green ball indication for permissive left-turn signals in the presence of separate signal heads. Currently, : there are no clear gui...

  5. 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. © 2015 John Wiley & Sons, Ltd.

  6. 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…

  7. Modified zeolitic imidazolate framework-8 as solid-phase microextraction Arrow coating for sampling of amines in wastewater and food samples followed by gas chromatography-mass spectrometry.

    PubMed

    Lan, Hangzhen; Rönkkö, Tuukka; Parshintsev, Jevgeni; Hartonen, Kari; Gan, Ning; Sakeye, Motolani; Sarfraz, Jawad; Riekkola, Marja-Liisa

    2017-02-24

    In this study, a novel solid phase microextration (SPME) Arrow was prepared for the sampling of volatile low molecular weight alkylamines (trimethylamine (TMA) and triethylamine (TEA)) in wastewater, salmon and mushroom samples before gas chromatographic separation with mass spectrometer as detector. Acidified zeolitic imidazolate framework-8 (A-ZIF-8) was utilized as adsorbent and poly(vinyl chloride) (PVC) as the adhesive. The custom SPME Arrow was fabricated via a physical adhesion: (1) ZIF-8 particles were suspended in a mixture of tetrahydrofuran (THF) and PVC to form a homogeneous suspension, (2) a non-coated stainless steel SPME Arrow was dipped in the ZIF-8/PVC suspension for several times to obtain a uniform and thick coating, (3) the pore size of ZIF-8 was modified by headspace exposure to hydrochloric acid in order to increase the extraction efficiency for amines. The effect of ZIF-8 concentration in PVC solution, dipping cycles and aging temperature on extraction efficiency was investigated. In addition, sampling parameters such as NaCl concentration, sample volume, extraction time, potassium hydroxide concentration, desorption temperature and desorption time were optimized. The Arrow-to-Arrow reproducibilities (RSDs) for five ZIF-8 coated Arrows were 15.6% and 13.3% for TMA and TEA, respectively. The extraction with A-ZIF-8/PVC Arrow was highly reproducible for at least 130 cycles without noticeable decrease of performance (RSD<12.5%). Headspace SPME of 7.5mL sample solution with the fabricated ZIF-8 coated Arrow achieved linear ranges of 1-200ngmL -1 for both TMA and TEA. The limit of quantitation (LOQ) was 1ngmL -1 for both TMA and TEA. The method was successfully applied to the determination of TMA and TEA in wastewater, salmon and mushroom samples giving satisfactory selectivity towards the studied amines. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The Arrow of Time In a Universe with a Positive Cosmological Constant Λ

    NASA Astrophysics Data System (ADS)

    Mersini-Houghton, Laura

    There is a mounting evidence that our universe is propelled into an accelerated expansion driven by Dark Energy. The simplest form of Dark Energy is a cosmological constant Λ, which is woven into the fabric of spacetime. For this reason it is often referred to as vacuum energy. It has the "strange" property of maintaining a constant energy density despite the expanding volume of the universe. Universes whose energy ismade of Λ posses an event horizon with and eternally finite constant temperature and entropy, and are known as DeSitter geometries. Since the entropy of DeSitter spaces remains a finite constant, then the meaning of a thermodynamic arrow of time becomes unclear. Here we explore the consequences of a fundamental cosmological constant Λ for our universe. We show that when the gravitational entropy of a pure DeSitter state ultimately dominates over the matter entropy, then the thermodynamic arrow of time in our universe may reverse in scales of order a Hubble time. We find that due to the dynamics of gravity and entanglement with other domain, a finite size system such as a DeSitter patch with horizon size H 0 -1 has a finite lifetime ∆t. This phenomenon arises from the dynamic gravitational instabilities that develop during a DeSitter epoch and turn catastrophic. A reversed arrow of time is in disagreementwith observations. Thus we explore the possibilities that: Nature may not favor a fundamental Λ, or else general relativity may be modified in the infrared regime when Λ dominates the expansion of the Universe.

  9. Language of Mechanisms: Exam Analysis Reveals Students' Strengths, Strategies, and Errors When Using the Electron-Pushing Formalism (Curved Arrows) in New Reactions

    ERIC Educational Resources Information Center

    Flynn, Alison B.; Featherstone, Ryan B.

    2017-01-01

    This study investigated students' successes, strategies, and common errors in their answers to questions that involved the electron-pushing (curved arrow) formalism (EPF), part of organic chemistry's language. We analyzed students' answers to two question types on midterms and final exams: (1) draw the electron-pushing arrows of a reaction step,…

  10. Safety implications of the use of the flashing yellow arrow for permissive left turns.

    DOT National Transportation Integrated Search

    2011-01-01

    The use of the flashing yellow arrow (FYA) for permissive left turns is relatively new to California, with at least five : installations approved under a 2006 Federal Highway Administration (FHWA) Interim Approval memorandum. : Inclusion of formal gu...

  11. 78 FR 72720 - Arrow Investment Advisors, LLC, et al.; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-03

    ... SECURITIES AND EXCHANGE COMMISSION [Investment Company Act Release No. 30813; File No. 812-14157] Arrow Investment Advisors, LLC, et al.; Notice of Application November 26, 2013. AGENCY: Securities and...(d), and 22(e) of the Act and rule 22c-1 under the Act, under sections 6(c) and 17(b) of the Act for...

  12. The physics of time and the arrow thereof

    NASA Astrophysics Data System (ADS)

    Hecht, Eugene

    2018-01-01

    Although the physics of time is of fundamental importance, the concept gets little attention in most introductory courses. Still, we now know enough to begin to formulate a coherent account of the physical nature of time. Newton’s absolute time has given way to Leibniz’s relational time. From Relativity Theory we learn that time in addition to being relational is also relative, and local; as we will see, the rates at which events unfold are influenced by both the relative velocity of the observer, and the local gravitational field strength—time is not universal. The intrinsic relationship between light-speed and time will be examined via relativity. Moreover, it will be shown that the Special Theory requires that the quanta of the electromagnetic field (i.e. photons), only exist at speed c; the ramifications of that extraordinary property, coupled with conservation of energy, profoundly influence the progression of time. Time in our everyday lives is the abstract measure of the unfolding of macroscopic occurrences, all of which are irreversible. It is posited that these events are irreversible because they are invariably accompanied by the emission of radiant energy, photons and/or gravitons. By contrast, entropy is a descriptor of processes, it is not a causative agency; although correlated with the so-called arrow-of-time, it cannot be its cause. Using a variety of physical thought experiments, it will be shown that the unidirectional ‘flow’ of time, the arrow-of-time, is a result of the fact that energy quanta only travel toward the future. That is the fundamental asymmetry in our otherwise temporally symmetric physics.

  13. The Decoherence and Interference of Cosmological Arrows of Time for a de Sitter Universe with Quantum Fluctuations

    NASA Astrophysics Data System (ADS)

    Rotondo, Marcello; Nambu, Yasusada

    2018-06-01

    We consider the superposition of two semiclassical solutions of the Wheeler-DeWitt equation for a de Sitter universe, describing a quantized scalar vacuum propagating in a universe that is contracting in one case and expanding in the other, each identifying a opposite cosmological arrow of time. We discuss the suppression of the interference terms between the two arrows of time due to environment-induced decoherence caused by modes of the scalar vacuum crossing the Hubble horizon. Furthermore, we quantify the effect of the interference on the expectation value of the observable field mode correlations, with respect to an observer that we identify with the spatial geometry.

  14. Development of guidelines for permitted left-turn phasing using flashing yellow arrows : final report.

    DOT National Transportation Integrated Search

    2015-06-01

    The objective of this project was to develop guidelines for time-of-day use of permitted left-turn phasing, : which can then be implemented using flashing yellow arrows (FYA). This required determining how the risk : for left-turn crashes varied as t...

  15. Early Twentieth Century Arrow, Javelin, and Dart Games of the Western Native American.

    ERIC Educational Resources Information Center

    Pesavento, Wilma J.

    The general purpose of this study was to determine whether the traditional native American ball games continued to be positive culture traits of the American Indian in the early twentieth century. The investigation was centered about (1) determining the current arrow, javelin, and dart games of western native Americans, (2) determining the…

  16. 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.

  17. Javelin, Arrow, Dart and Pin Games of Native American Women of the Plains.

    ERIC Educational Resources Information Center

    Pesavento, Wilma J.; Pesavento, Lisa C.

    This study was designed to determine (1) the arrow, dart, javelin, and pin games of Native American girls and women of the Great Plains, (2) the geographical spread of the games within the culture area, and (3) the characteristics of the various games. Data for this investigation were researched from "Annual Reports of the Bureau of American…

  18. 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.

  19. 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…

  20. 26 CFR 48.4161(b)-1 - Imposition and rates of tax; bows and arrows.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Imposition and rates of tax; bows and arrows. 48.4161(b)-1 Section 48.4161(b)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Sporting Goods § 48.4161(b)-1...

  1. Structure of the thermodynamic arrow of time in classical and quantum theories

    NASA Astrophysics Data System (ADS)

    Korzekwa, Kamil

    2017-05-01

    In this work we analyze the structure of the thermodynamic arrow of time, defined by transformations that leave the thermal equilibrium state unchanged, in classical (incoherent) and quantum (coherent) regimes. We note that in the infinite-temperature limit, the thermodynamic ordering of states in both regimes exhibits a lattice structure. This means that when energy does not matter and the only thermodynamic resource is given by information, the thermodynamic arrow of time has a very specific structure. Namely, for any two states at present there exists a unique state in the past consistent with them and with all possible joint pasts. Similarly, there also exists a unique state in the future consistent with those states and with all possible joint futures. We also show that the lattice structure in the classical regime is broken at finite temperatures, i.e., when energy is a relevant thermodynamic resource. Surprisingly, however, we prove that in the simplest quantum scenario of a two-dimensional system, this structure is preserved at finite temperatures. We provide the physical interpretation of these results by introducing and analyzing the history erasure process, and point out that quantum coherence may be a necessary resource for the existence of an optimal erasure process.

  2. Failure strength of a new meniscus arrow repair technique: biomechanical comparison with horizontal suture.

    PubMed

    Albrecht-Olsen, P; Lind, T; Kristensen, G; Falkenberg, B

    1997-04-01

    A new method for arthroscopic all-inside repair of vertical meniscus lesions by use of a biodegradable fixation device ("meniscus arrow") has been developed, including a set of cannulas for easy insertion via standard arthroscopic portals. The technique is described. A study to test the fixation properties was performed in the laboratory. Twenty-four fresh frozen bovine medial menisci were defreezed and divided into three groups. In all menisci an artificial vertical lesion was created with a scalpel 3mm from the peripheral rim. Repair in group I was done with a single horizontal Maxon-O suture using an Acufex double-barrel cannula (Acufex Meniscal Stitcher; Acufex Microsurgical, Norwood, MA). A knot was tied on the capsular side. Repair in group II was made with one 13 mm Biofix Meniscus arrow (Bioscience Ltd, Tampere, Finland). In group III repair was performed like in group II but the menisci were incubated in isotonic saline at 21 degrees C for 24 hours before testing. Menisci in group I and II were tested within 3 hours after defreezing. Prior to testing total separation of central and peripheral part of meniscus was performed. Thus only the repair site was tested. Pull-out tests to failure were made in a computer-based Nene M5 testing machine with a cross-head speed of 5 mm/min. Median failure load in group I: 49 N (range 43 to 77 N), in group II: 53 N (range 42 to 65 N) and in group III: 54 N (range 35 to 74 N). No statistically significant differences in failure load was found between the groups. Thus initial failure strength for arrow-repaired bovine menisci is comparable to that of a horizontal suture.

  3. 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…

  4. 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…

  5. Rate constants for CF{sub 3} + H{sub 2} {r_arrow} CF{sub 3}H + H and CF{sub 3}H + H {r_arrow} CF{sub 3} + H{sub 2} reactions in the temperature range 1100--1600 K

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

    Hranisavljevic, J.; Michael, J.V.

    1998-09-24

    The shock tube technique coupled with H-atom atomic resonance absorption spectrometry has been used to study the reactions (1) CF{sub 3} + H{sub 2} {r_arrow} CF{sub 3}H + H and (2) CF{sub 3}H + H {r_arrow} CF{sub 3} + H{sub 2} over the temperature ranges 1168--1673 K and 1111--1550 K, respectively. The results can be represented by the Arrhenius expressions k{sub 1} = 2.56 {times} 10{sup {minus}11} exp({minus}8549K/T) and k{sub 2} = 6.13 {times} 10{sup {minus}11} exp({minus}7364K/T), both in cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. Equilibrium constants were calculated from the two Arrhenius expressions in the overlapping temperature range, andmore » good agreement was obtained with the literature values. The rate constants for reaction 2 were converted into rate constants for reaction 1 using literature equilibrium constants. These data are indistinguishable from direct k{sub 1} measurements, and an Arrhenius fit for the joint set is k{sub 1} = 1.88 {times} 10{sup {minus}11} exp({minus}8185K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. The CF{sub 3} + H{sub 2} {r_arrow} CF{sub 3}H + H reaction was further modeled using conventional transition-state theory, which included ab initio electronic structure determinations of reactants, transition state, and products.« less

  6. Electron impact excitation of the q{sup 1}S {r_arrow}n{sup 1}P (n=3,4) transitions in helium

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

    Khakoo, M.A.; Rugamas, F.; Roundy, D.

    1996-05-01

    Experimental differential cross-section (DCS) ratios for the above transitions to the 1{sup 1}S {r_arrow} 2{sup 1}P transition are reported at impact energies of 30eV, 40eV and 80eV and scattering angles in the range of 5{degrees} to 130{degrees}. The data are an extension of previously reported work using the electron-photon coincidence method in the VUV. The DCS ratios are normalized to available absolute DCSs for the 1{sup 1}S {r_arrow} 2{sup 1}P transition and the resulting n{sup 1}P DCSs are compared to previous semi-empirical DCSs as well as available theory.

  7. Search for Proton Decay via {ital p} {r_arrow} {ital e}{sup +}{ital {pi}}{sup 0} in a Large Water Cherenkov Detector

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

    Shiozawa, M.; Fukuda, Y.; Hayakawa, T.

    1998-10-01

    We have searched for proton decay via p{r_arrow}e{sup +}{pi}{sup 0} using data from a 25.5 kton{center_dot}yr exposure of the Super-Kamiokande detector. We find no candidate events with an expected background induced by atmospheric neutrinos of 0.1thinspthinspevents. From these data, we set a lower limit on the partial lifetime of the proton {tau}/B{sub p{r_arrow}e{sup +}{pi}{sup 0}} to be 1.6{times}10{sup 33} years at a 90{percent} confidence level. {copyright} {ital 1998} {ital The American Physical Society }

  8. NRC, SPI, and chasing arrows: Is there common ground

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

    Rabasca, L.

    After negotiating for 15 months, issuing three white papers, and conducting consumer research, the National Recycling Coalition (NRC, Washington, DC) and the Society of the Plastics Industry, Inc. (SPI, Washington, DC), have agreed to disagree on the use of the familiar chasing arrows logo in SPI's seven-number resin identification code. The desired end result of the talks and debates was supposed to be a plan to change legislation requiring 39 states to use SPI's current resin identification code and a commitment to remove the old code from durable goods and flexible packaging. Ultimately, these actions could have improved markets formore » polyethylene terephthalate (PET) and high-density polyethylene (HDPE) by reducing contamination caused by confusion over what is actually recycled versus what is merely recyclable.« less

  9. The Geohistorical Time Arrow: From Steno's Stratigraphic Principles to Boltzmann's Past Hypothesis

    ERIC Educational Resources Information Center

    Kravitz, Gadi

    2014-01-01

    Geologists have always embraced the time arrow in order to reconstruct the past geology of Earth, thus turning geology into a historical science. The covert assumption regarding the direction of time from past to present appears in Nicolas Steno's principles of stratigraphy. The intuitive-metaphysical nature of Steno's assumption was based on a…

  10. Public opinion and understanding of advance warning arrow displays used in short-term, mobile, and moving work zones.

    DOT National Transportation Integrated Search

    2008-03-01

    "In long-term work zones on multilane highways and/or freeways, the Federal Highway Administration has interpreted the : Manual on Uniform Traffic Control Devices to mean that only one advance warning arrow displays can be used to denote : the closur...

  11. 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

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

    PubMed

    Loewer, Barry

    2012-02-06

    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.

  13. Is the hypothesis about a low entropy initial state of the Universe necessary for explaining the arrow of time?

    NASA Astrophysics Data System (ADS)

    Goldstein, Sheldon; Tumulka, Roderich; Zanghı, Nino

    2016-07-01

    According to statistical mechanics, microstates of an isolated physical system (say, a gas in a box) at time t0 in a given macrostate of less-than-maximal entropy typically evolve in such a way that the entropy at time t increases with |t -t0| in both time directions. In order to account for the observed entropy increase in only one time direction, the thermodynamic arrow of time, one usually appeals to the hypothesis that the initial state of the Universe was one of very low entropy. In certain recent models of cosmology, however, no hypothesis about the initial state of the Universe is invoked. We discuss how the emergence of a thermodynamic arrow of time in such models can nevertheless be compatible with the above-mentioned consequence of statistical mechanics, appearances to the contrary notwithstanding.

  14. 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

  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

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

    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; mutationsmore » 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.« less

  16. 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.

  17. 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.

  18. Field measurements of biogenic volatile organic compounds in the atmosphere using solid-phase microextraction Arrow

    NASA Astrophysics Data System (ADS)

    Feijó Barreira, Luís Miguel; Duporté, Geoffroy; Rönkkö, Tuukka; Parshintsev, Jevgeni; Hartonen, Kari; Hyrsky, Lydia; Heikkinen, Enna; Jussila, Matti; Kulmala, Markku; Riekkola, Marja-Liisa

    2018-02-01

    Biogenic volatile organic compounds (BVOCs) emitted by terrestrial vegetation participate in a diversity of natural processes. These compounds impact both short-range processes, such as on plant protection and communication, and long-range processes, for example by participating in aerosol particle formation and growth. The biodiversity of plant species around the Earth, the vast assortment of emitted BVOCs, and their trace atmospheric concentrations contribute to the substantial remaining uncertainties about the effects of these compounds on atmospheric chemistry and physics, and call for the development of novel collection devices that can offer portability with improved selectivity and capacity. In this study, a novel solid-phase microextraction (SPME) Arrow sampling system was used for the static and dynamic collection of BVOCs from a boreal forest, and samples were subsequently analyzed on site by gas chromatography-mass spectrometry (GC-MS). This system offers higher sampling capacity and improved robustness when compared to traditional equilibrium-based SPME techniques, such as SPME fibers. Field measurements were performed in summer 2017 at the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II) in Hyytiälä, Finland. Complementary laboratory tests were also performed to compare the SPME-based techniques under controlled experimental conditions and to evaluate the effect of temperature and relative humidity on their extraction performance. The most abundant monoterpenes and aldehydes were successfully collected. A significant improvement on sampling capacity was observed with the new SPME Arrow system over SPME fibers, with collected amounts being approximately 2 × higher for monoterpenes and 7-8 × higher for aldehydes. BVOC species exhibited different affinities for the type of sorbent materials used (polydimethylsiloxane (PDMS)-carbon wide range (WR) vs. PDMS-divinylbenzene (DVB)). Higher extraction efficiencies were obtained with dynamic

  19. PTEN Regulates Beta-Catenin in Androgen Signaling: Implication in Prostate Cancer Progression

    DTIC Science & Technology

    2006-03-01

    interacts with a single transmembrane LDL receptor-related protein 5/6 (LRP5/6) [14,15]. A number of different secreted proteins, such as secreted...cells [30,33,47,48,51]. Reduction of cellular levels of b-catenin by antisense or shRNA constructs decreases the expression of the PSA gene, a downstream...Zeng, LDL receptor- related proteins 5 and 6 inWnt/beta-catenin signaling: arrows point the way, Development 131 (2004) 1663–1677. [15] J.C. Hsieh

  20. 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…

  1. 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.

  2. Controlling Attention to Gaze and Arrows in Childhood: An fMRI Study of Typical Development and Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Vaidya, Chandan J.; Foss-Feig, Jennifer; Shook, Devon; Kaplan, Lauren; Kenworthy, Lauren; Gaillard, William D.

    2011-01-01

    Functional magnetic resonance imaging was used to examine functional anatomy of attention to social (eye gaze) and nonsocial (arrow) communicative stimuli in late childhood and in a disorder defined by atypical processing of social stimuli, Autism Spectrum Disorders (ASD). Children responded to a target word ("LEFT"/"RIGHT") in the context of a…

  3. 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.

  4. 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.

  5. Prediction of cyclohexane-water distribution coefficient for SAMPL5 drug-like compounds with the QMPFF3 and ARROW polarizable force fields.

    PubMed

    Kamath, Ganesh; Kurnikov, Igor; Fain, Boris; Leontyev, Igor; Illarionov, Alexey; Butin, Oleg; Olevanov, Michael; Pereyaslavets, Leonid

    2016-11-01

    We present the performance of blind predictions of water-cyclohexane distribution coefficients for 53 drug-like compounds in the SAMPL5 challenge by three methods currently in use within our group. Two of them utilize QMPFF3 and ARROW, polarizable force-fields of varying complexity, and the third uses the General Amber Force-Field (GAFF). The polarizable FF's are implemented in an in-house MD package, Arbalest. We find that when we had time to parametrize the functional groups with care (batch 0), the polarizable force-fields outperformed the non-polarizable one. Conversely, on the full set of 53 compounds, GAFF performed better than both QMPFF3 and ARROW. We also describe the torsion-restrain method we used to improve sampling of molecular conformational space and thus the overall accuracy of prediction. The SAMPL5 challenge highlighted several drawbacks of our force-fields, such as our significant systematic over-estimation of hydrophobic interactions, specifically for alkanes and aromatic rings.

  6. Solid phase microextraction Arrow for the sampling of volatile amines in wastewater and atmosphere.

    PubMed

    Helin, Aku; Rönkkö, Tuukka; Parshintsev, Jevgeni; Hartonen, Kari; Schilling, Beat; Läubli, Thomas; Riekkola, Marja-Liisa

    2015-12-24

    A new method is introduced for the sampling of volatile low molecular weight alkylamines in ambient air and wastewater by utilizing a novel SPME Arrow system, which contains a larger volume of sorbent compared to a standard SPME fiber. Parameters affecting the extraction, such as coating material, need for preconcentration, sample volume, pH, stirring rate, salt addition, extraction time and temperature were carefully optimized. In addition, analysis conditions, including desorption temperature and time as well as gas chromatographic parameters, were optimized. Compared to conventional SPME fiber, the SPME Arrow had better robustness and sensitivity. Average intermediate reproducibility of the method expressed as relative standard deviation was 12% for dimethylamine and 14% for trimethylamine, and their limit of quantification 10μg/L and 0.13μg/L respectively. Working range was from limits of quantification to 500μg/L for dimethylamine and to 130μg/L for trimethylamine. Several alkylamines were qualitatively analyzed in real samples, while target compounds dimethyl- and trimethylamines were quantified. The concentrations in influent and effluent wastewater samples were almost the same (∼80μg/L for dimethylamine, 120μg/L for trimethylamine) meaning that amines pass the water purification process unchanged or they are produced at the same rate as they are removed. For the air samples, preconcentration with phosphoric acid coated denuder was required and the concentration of trimethylamine was found to be around 1ng/m(3). The developed method was compared with optimized method based on conventional SPME and advantages and disadvantages of both approaches are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Propulsive-lift concepts for improved low-speed performance of supersonic cruise arrow-wing configurations

    NASA Technical Reports Server (NTRS)

    Coe, P. L., Jr.

    1976-01-01

    Low-aspect-ratio highly swept arrow-wing supersonic aircraft possess high levels of aerodynamic efficiency at supersonic cruising speeds, however, their inherently poor low-speed lift characteristics require design constraints that compromise supersonic performance. The data discussed in this paper were obtained in wind tunnel tests with supersonic crusing configurations, in which propulsive-lift concepts were used to improve low-speed performance. The data show that the increased low-speed lift provided by propulsive-lift permits reduction of both wing size and installed thrust. This yields a batter engine/airframe match for improved supersonic cruise efficiency and range, while still providing acceptable take-off field lengths.

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. A comparison of arrow, trapezoidal and M wing concepts using a Mach 2 supersonic cruise transport mission

    NASA Technical Reports Server (NTRS)

    Martin, Glenn L.; Tice, David C.; Marcum, Don C., Jr.; Seidel, Jonathan A.

    1991-01-01

    The present analytic study of the potential performance of SST configurations radically differing from arrow-winged designs in lifting surface planform geometry gives attention to trapezoidal-wing and M-wing configurations; the trapezoidal wing is used as the baseline in the performance comparisons. The design mission was all-supersonic (Mach 2), carrying 248 passengers over a 5500 nautical-mile range. Design constraints encompassed approach speed, TO&L field length, and engine-out second-segment climb and missed-approach performance. Techniques for improving these configurations are discussed.

  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…

  14. 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.

  15. 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

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

    Feigenbaum, A.; Chitayat, D.; Robinson, B.

    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 hadmore » 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.« less

  16. Occasion Setting Is Specific to the CS-US Association

    ERIC Educational Resources Information Center

    Bonardi, Charlotte

    2007-01-01

    In Experiment 1, rats were trained on a discrimination in which one occasion setter, A, signaled that one cue (conditioned stimulus, CS), x, would be followed by one outcome, p (unconditioned stimulus, US), and a second CS, y, by a different outcome, q (x [right arrow] p and y [right arrow] q); a second occasion setter, B signalled the reverse…

  17. 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.

  18. 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…

  19. CSMP Mathematics for the Upper Primary Grades Part II, 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 an extended pilot project which was conducted in the United States between 1973 and 1976. The manner of presentation and the pedagogical ideas and tools are based on the works of Georges and Frederique Papy. They are recognized as having introduced colored arrow drawings…

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

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

    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, causingmore » 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.« less

  1. CSMP Mathematics for the Intermediate Grades. Part V. Teacher's Guide. The Languages of Strings and Arrows. Geometry and Measurement. Probability and Statistics. Experimental Version.

    ERIC Educational Resources Information Center

    CEMREL, Inc., St. Louis, MO.

    This Comprehensive School Mathematics Program (CSMP) guide is divided into three major parts. The first, the Languages of Strings and Arrows, opens with a suggested lesson order. Major sections cover instructional approaches for: (1) Games with Strings, (2) Necklaces, and (3) The Table Game. A Series of appendices is included. Part 2, Geometry and…

  2. CSMP Mathematics for the Intermediate Grades Part II, Teacher's Guide. The Languages of Strings and Arrows. Geometry and Measurement. Probability and Statistics. Experimental Version.

    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…

  3. CSMP Mathematics for the Intermediate Grades Part III, Teacher's Guide. The Languages of Strings and Arrows. Geometry and Measurement. Probability and Statistics. Experimental Version.

    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…

  4. 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

  5. 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…

  6. Analysis and Inverse Design of the HSR Arrow Wing Configuration with Fuselage, Wing, and Flow Through Nacelles

    NASA Technical Reports Server (NTRS)

    Krist, Steven E.; Bauer, Steven X. S.

    1999-01-01

    The design process for developing the natural flow wing design on the HSR arrow wing configuration utilized several design tools and analysis methods. Initial fuselage/wing designs were generated with inviscid analysis and optimization methods in conjunction with the natural flow wing design philosophy. A number of designs were generated, satisfying different system constraints. Of the three natural flow wing designs developed, the NFWAc2 configuration is the design which satisfies the constraints utilized by McDonnell Douglas Aerospace (MDA) in developing a series of optimized configurations; a wind tunnel model of the MDA designed OPT5 configuration was constructed and tested. The present paper is concerned with the viscous analysis and inverse design of the arrow wing configurations, including the effects of the installed diverters/nacelles. Analyses were conducted with OVERFLOW, a Navier-Stokes flow solver for overset grids. Inverse designs were conducted with OVERDISC, which couples OVERFLOW with the CDISC inverse design method. An initial system of overset grids was generated for the OPT5 configuration with installed diverters/nacelles. An automated regridding process was then developed to use the OPT5 component grids to create grids for the natural flow wing designs. The inverse design process was initiated using the NFWAc2 configuration as a starting point, eventually culminating in the NFWAc4 design-for which a wind tunnel model was constructed. Due to the time constraints on the design effort, initial analyses and designs were conducted with a fairly coarse grid; subsequent analyses have been conducted on a refined system of grids. Comparisons of the computational results to experiment are provided at the end of this paper.

  7. Entanglement versus Stosszahlansatz: disappearance of the thermodynamic arrow in a high-correlation environment.

    PubMed

    Partovi, M Hossein

    2008-02-01

    The crucial role of ambient correlations in determining thermodynamic behavior is established. A class of entangled states of two macroscopic systems is constructed such that each component is in a state of thermal equilibrium at a given temperature, and when the two are allowed to interact heat can flow from the colder to the hotter system. A dilute gas model exhibiting this behavior is presented. This reversal of the thermodynamic arrow is a consequence of the entanglement between the two systems, a condition that is opposite to molecular chaos and shown to be unlikely in a low-entropy environment. By contrast, the second law is established by proving Clausius' inequality in a low-entropy environment. These general results strongly support the expectation, first expressed by Boltzmann and subsequently elaborated by others, that the second law is an emergent phenomenon which requires a low-entropy cosmological environment, one that can effectively function as an ideal information sink.

  8. Vein rupture by Arrow-Trerotola percutaneous thrombolytic device in a treatment of thrombosed arteriovenous graft.

    PubMed

    Hong, Yong Kook; Kang, Kyung Hoon; Kim, Tae Hwan; Yang, Hee Chul

    2018-03-01

    We report a case of vein rupture by Arrow-Trerotola percutaneous thrombolytic device (Trerotola PTD) during a treatment of thrombosed arteriovenous graft (AVG). A 77-year-old woman with a problem of thrombosed AVG underwent an endovascular treatment including a procedure of angioplasty of axillary vein. After angioplasty of axillary vein, we found a newly developed thrombus in axillary vein and performed thrombolysis using an over-the-wire 7F Trerotola PTD. When the rotating cage of the device arrived at axillary vein, it suddenly stopped, fixed at the angioplasty site, and didn't move at all. Venogram showed an extravasation of contrast media at axillary vein, suggesting vein rupture. The patient underwent an emergency operation. It could be dangerous to use Trerotola PTD in a native vein immediately after angioplasty.

  9. 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. © 2014. Published by The Company of Biologists Ltd.

  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. The Arrow of Time and the Action of the Mind at the Molecular Level

    NASA Astrophysics Data System (ADS)

    Burns, Jean E.

    2006-10-01

    A new event is defined as an intervention in the time reversible dynamical trajectories of particles in a system. New events are then assumed to be quantum fluctuations in the spatial and momentum coordinates, and mental action is assumed to work by ordering such fluctuations. It is shown that when the cumulative values of such fluctuations in a mean free path of a molecule are magnified by molecular interaction at the end of that path, the momentum of a molecule can be changed from its original direction to any other direction. In this way mental action can produce effects through the ordering of thermal motions. Examples are given which show that the ordering of 104-105 molecules is sufficient to (a) produce detectible PK results and (b) open sufficient ion channels in the brain to initiate a physical action. The relationship of the above model to the arrow of time is discussed.

  12. Pressure data for four analytically defined arrow wings in supersonic flow. [Langley Unitary Plan Wind Tunnel tests

    NASA Technical Reports Server (NTRS)

    Townsend, J. C.

    1980-01-01

    In order to provide experimental data for comparison with newly developed finite difference methods for computing supersonic flows over aircraft configurations, wind tunnel tests were conducted on four arrow wing models. The models were machined under numeric control to precisely duplicate analytically defined shapes. They were heavily instrumented with pressure orifices at several cross sections ahead of and in the region where there is a gap between the body and the wing trailing edge. The test Mach numbers were 2.36, 2.96, and 4.63. Tabulated pressure data for the complete test series are presented along with selected oil flow photographs. Comparisons of some preliminary numerical results at zero angle of attack show good to excellent agreement with the experimental pressure distributions.

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

    PubMed

    Wright, L Kate; 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. © 2014 L. K. Wright et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  14. Absolute becoming, relational becoming and the arrow of time: Some non-conventional remarks on the relationship between physics and metaphysics

    NASA Astrophysics Data System (ADS)

    Dorato, Mauro

    The literature on the compatibility between the time of our experience-characterized by passage or becoming-and time as is represented within spacetime theories has been affected by a persistent failure to get a clear grasp of the notion of becoming, both in its relation to an ontology of events "spread" in a four-dimensional manifold, and in relation to temporally asymmetric physical processes. In the first part of my paper I try to remedy this situation by offering what I consider a clear and faithful explication of becoming, valid independently of the particular spacetime setting in which we operate. Along the way, I will show why the metaphysical debate between the so-called "presentists" and "eternalists" is completely irrelevant to the question of becoming, as the debate itself is generated by a failure to distinguish between a tensed and a tenseless sense of "existence". After a much needed distinction between absolute and relational becoming, I then show in what sense classical (non-quantum) spacetime physics presupposes both types of becoming, for the simple reason that spacetime physics presupposes an ontology of (timelike-separated) events. As a consequence, not only does it turn out that using physics to try to provide empirical evidence for the existence of becoming amounts to putting the cart before the horses, but also that the order imposed by "the arrow of becoming" is more fundamental than any other physical arrow of time, despite the fact that becoming cannot be used to explain why entropy grows, or retarded electromagnetic radiation prevails versus advanced radiation.

  15. Micro-simulation of vehicle conflicts involving right-turn vehicles at signalized intersections based on cellular automata.

    PubMed

    Chai, C; Wong, Y D

    2014-02-01

    At intersection, vehicles coming from different directions conflict with each other. Improper geometric design and signal settings at signalized intersection will increase occurrence of conflicts between road users and results in a reduction of the safety level. This study established a cellular automata (CA) model to simulate vehicular interactions involving right-turn vehicles (as similar to left-turn vehicles in US). Through various simulation scenarios for four case cross-intersections, the relationships between conflict occurrences involving right-turn vehicles with traffic volume and right-turn movement control strategies are analyzed. Impacts of traffic volume, permissive right-turn compared to red-amber-green (RAG) arrow, shared straight-through and right-turn lane as well as signal setting are estimated from simulation results. The simulation model is found to be able to provide reasonable assessment of conflicts through comparison of existed simulation approach and observed accidents. Through the proposed approach, prediction models for occurrences and severity of vehicle conflicts can be developed for various geometric layouts and traffic control strategies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. NF1 Signal Transduction and Vascular Dysfunction

    DTIC Science & Technology

    2014-05-01

    presence of the Cad5:ERT allele, the Rosa26 LSL- tomato reporter, a floxed NF1 allele and the presence of a NF1 mutant (deletion) allele. Green arrows indicate mouse pups positive for all 4 selected alleles. 23

  17. Integrated atomic layer deposition and chemical vapor reaction for the preparation of metal organic framework coatings for solid-phase microextraction Arrow.

    PubMed

    Lan, Hangzhen; Salmi, Leo D; Rönkkö, Tuukka; Parshintsev, Jevgeni; Jussila, Matti; Hartonen, Kari; Kemell, Marianna; Riekkola, Marja-Liisa

    2018-09-18

    New chemical vapor reaction (CVR) and atomic layer deposition (ALD)-conversion methods were utilized for preparation of metal organic frameworks (MOFs) coatings of solid phase microextraction (SPME) Arrow for the first time. With simple, easy and convenient one-step reaction or conversion, four MOF coatings were made by suspend ALD iron oxide (Fe 2 O 3 ) film or aluminum oxide (Al 2 O 3 ) film above terephthalic acid (H 2 BDC) or trimesic acid (H 3 BTC) vapor. UIO-66 coating was made by zirconium (Zr)-BDC film in acetic acid vapor. As the first documented instance of all-gas phase synthesis of SPME Arrow coatings, preparation parameters including CVR/conversion time and temperature, acetic acid volume, and metal oxide film/metal-ligand films thickness were investigated. The optimal coatings exhibited crystalline structures, excellent uniformity, satisfactory thickness (2-7.5 μm), and high robustness (>80 times usage). To study the practical usefulness of the coatings for the extraction, several analytes with different chemical properties were tested. The Fe-BDC coating was found to be the most selective and sensitive for the determination of benzene ring contained compounds due to its highly hydrophobic surface and unsaturated metal site. UIO-66 coating was best for small polar, aromatic, and long chain polar compounds owing to its high porosity. The usefulness of new coatings were evaluated for gas chromatography-mass spectrometer (GC-MS) determination of several analytes, present in wastewater samples at three levels of concentration, and satisfactory results were achieved. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Photon Tagger Timing Calibration for the Rad Phi Experiment

    NASA Astrophysics Data System (ADS)

    Russell, Mammei; Smith, Elton

    2000-10-01

    Vector mesons provide a rich laboratory for the study of fundamental physics and radiative decays probe the very nature of the internal structure of these mesons, which possess the same quantum numbers of photons. Experiment E94-016, which collected data this past summer in Hall B of the Thomas Jefferson National Accelerator Facility (JLab), has measured the the branching ratios for rare radiative decays of the phi meson, i.e. φarrow f_0(975)γ arrow π^0π^0γ, φ arrow a_0(980)γ arrow π0 η γ, and φ arrow η'γ. A lead glass calorimeter, in concert with several detectors, measured these decays. A tagged beam of bremsstrahlung photons was directed upon a solid Beryllium target. A three-level trigger was then employed to preferentially select radiative decays of the φ meson. We calibrated timing of each detector by referencing individual detectors to one another. Tight timing will enhance signal relative to background.

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

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

    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%)more » 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.« less

  20. 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.

  1. Low-speed aerodynamic characteristics from wind-tunnel tests of a large-scale advanced arrow-wing supersonic-cruise transport concept

    NASA Technical Reports Server (NTRS)

    Smith, P. M.

    1978-01-01

    Tests have been conducted to extend the existing low speed aerodynamic data base of advanced supersonic-cruise arrow wing configurations. Principle configuration variables included wing leading-edge flap deflection, wing trailing-edge flap deflection, horizontal tail effectiveness, and fuselage forebody strakes. A limited investigation was also conducted to determine the low speed aerodynamic effects due to slotted training-edge flaps. Results of this investigation demonstrate that deflecting the wing leading-edge flaps downward to suppress the wing apex vortices provides improved static longitudinal stability; however, it also results in significantly reduced static directional stability. The use of a selected fuselage forebody strakes is found to be effective in increasing the level of positive static directional stability. Drooping the fuselage nose, which is required for low-speed pilot vision, significantly improves the later-directional trim characteristics.

  2. The Effects of Attention Cueing on Visualizers' Multimedia Learning

    ERIC Educational Resources Information Center

    Yang, Hui-Yu

    2016-01-01

    The present study examines how various types of attention cueing and cognitive preference affect learners' comprehension of a cardiovascular system and cognitive load. EFL learners were randomly assigned to one of four conditions: non-signal, static-blood-signal, static-blood-static-arrow-signal, and animation-signal. The results indicated that…

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

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

    Wildberger, Joachim Ernst, E-mail: wildberg@rad.rwth-aachen.de; Haage, Patrick; Bovelander, Jan

    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 beginningmore » 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

  4. A reaction time advantage for calculating beliefs over public representations signals domain specificity for 'theory of mind'.

    PubMed

    Cohen, Adam S; German, Tamsin C

    2010-06-01

    In a task where participants' overt task was to track the location of an object across a sequence of events, reaction times to unpredictable probes requiring an inference about a social agent's beliefs about the location of that object were obtained. Reaction times to false belief situations were faster than responses about the (false) contents of a map showing the location of the object (Experiment 1) and about the (false) direction of an arrow signaling the location of the object (Experiment 2). These results are consistent with developmental, neuro-imaging and neuropsychological evidence that there exist domain specific mechanisms within human cognition for encoding and reasoning about mental states. Specialization of these mechanisms may arise from either core cognitive architecture or via the accumulation of expertise in the social domain.

  5. 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.

  6. Is social attention impaired in schizophrenia? Gaze, but not pointing gestures, is associated with spatial attention deficits.

    PubMed

    Dalmaso, Mario; Galfano, Giovanni; Tarqui, Luana; Forti, Bruno; Castelli, Luigi

    2013-09-01

    The nature of possible impairments in orienting attention to social signals in schizophrenia is controversial. The present research was aimed at addressing this issue further by comparing gaze and arrow cues. Unlike previous studies, we also included pointing gestures as social cues, with the goal of addressing whether any eventual impairment in the attentional response was specific to gaze signals or reflected a more general deficit in dealing with social stimuli. Patients with schizophrenia or schizoaffective disorder and matched controls performed a spatial-cuing paradigm in which task-irrelevant centrally displayed gaze, pointing finger, and arrow cues oriented rightward or leftward, preceded a lateralized target requiring a simple detection response. Healthy controls responded faster to spatially congruent targets than to spatially incongruent targets, irrespective of cue type. In contrast, schizophrenic patients responded faster to spatially congruent targets than to spatially incongruent targets only for arrow and pointing finger cues. No cuing effect emerged for gaze cues. The results support the notion that gaze cuing is impaired in schizophrenia, and suggest that this deficit may not extend to all social cues.

  7. 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.

  8. WNT-1 Signaling in Mammary Carcinogenesis

    DTIC Science & Technology

    2002-04-01

    segment polarity gene whose mutant phenotype resembles that of the wingless (Drosophila Wnt-1) mutation (3). arrow encodes a transmembrane receptor...and function ofSpemann’s organizer. Annu. Rev. C Drv. of those caused by mutations in individual Wnt genes . Further- Biaol 13, 611-667 (1997). more, we... mutations of multiple Wnt genes [31]. In the 0.5 nM and thus is significantly higher than Wnt-Fz bind- Xenopus embryo, inhibition of LRP6 function

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

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

    PubMed

    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.

  15. Solid State Research

    DTIC Science & Technology

    1998-05-15

    2 Bioaerosol fluorescence sensor concept. 2 1-3 Bioaerosol fluorescence sensor detection geometry: (a) signal collection (side view... wavelength light, (b) Strength of output signal along vertical line trace indicated by arrow in (a). 37 5-2 Brick wall pattern revealed by chemical...etchant. 38 5-3 (a) Flat-field illumination of improved laser-annealed CCD at -90°C with 410-nm wavelength light, (b) Strength of output signal along

  16. A simple recipe for setting up the flux equations of cyclic and linear reaction schemes of ion transport with a high number of states: The arrow scheme.

    PubMed

    Hansen, Ulf-Peter; Rauh, Oliver; Schroeder, Indra

    2016-01-01

    The calculation of flux equations or current-voltage relationships in reaction kinetic models with a high number of states can be very cumbersome. Here, a recipe based on an arrow scheme is presented, which yields a straightforward access to the minimum form of the flux equations and the occupation probability of the involved states in cyclic and linear reaction schemes. This is extremely simple for cyclic schemes without branches. If branches are involved, the effort of setting up the equations is a little bit higher. However, also here a straightforward recipe making use of so-called reserve factors is provided for implementing the branches into the cyclic scheme, thus enabling also a simple treatment of such cases.

  17. Amyotrophic lateral sclerosis affects cortical and subcortical activity underlying motor inhibition and action monitoring.

    PubMed

    Mohammadi, Bahram; Kollewe, Katja; Cole, David M; Fellbrich, Anja; Heldmann, Marcus; Samii, Amir; Dengler, Reinhard; Petri, Susanne; Münte, Thomas F; Krämer, Ulrike M

    2015-08-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by muscular atrophy, spasticity, and bulbar signs caused by loss of upper and lower motor neurons. Evidence suggests that ALS additionally affects other brain areas including premotor cortex and supplementary motor area. Here, we studied movement execution and inhibition in ALS patients using a stop-signal paradigm and functional magnetic resonance imaging. Seventeen ALS patients and 17 age-matched healthy controls performed a stop-signal task that required responding with a button press to a right- or left-pointing black arrow (go-stimuli). In stop-trials, a red arrow (stop-stimulus) was presented shortly after the black arrow indicating to withhold the prepared movement. Patients had by trend higher reaction times in go-trials but did not differ significantly in their inhibition performance. Patients showed stronger inhibition-related activity in inferior, superior, and middle frontal gyri as well as in putamen and pallidum. Error-related activity, conversely, was found to be stronger in healthy controls, particularly in the insula bilaterally. Patients also showed increased activity in the motor cortex during button presses. The results provide evidence for altered prefrontal and subcortical networks underlying motor execution, motor inhibition, and error monitoring in ALS. © 2015 Wiley Periodicals, Inc.

  18. BRCA1 Regulation of Estrogen Signaling in the Breast

    DTIC Science & Technology

    2007-05-01

    PAGE and processed by immunoblot analysis with antibodies specific for GAL4- DBD or ER as indicated by arrows. Note that differences in the relative...derivative 1–150 (N terminus). Schematic diagrams of ER and DBC-1 indicate fragments used in binding reactions. AF-1, Activation function 1; DBD , DNA...solved by SDS-10% PAGE. Proteins were analyzed by im- munoblot using antibodies against GAL4- DBD (RK5C1; Santa Cruz Biotechnology, Santa Cruz, CA

  19. 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.

  20. Signal transfer within a cultured asymmetric cortical neuron circuit.

    PubMed

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

    2015-12-01

    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. 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. 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. 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.

  1. A simple recipe for setting up the flux equations of cyclic and linear reaction schemes of ion transport with a high number of states: The arrow scheme

    PubMed Central

    Hansen, Ulf-Peter; Rauh, Oliver; Schroeder, Indra

    2016-01-01

    abstract The calculation of flux equations or current-voltage relationships in reaction kinetic models with a high number of states can be very cumbersome. Here, a recipe based on an arrow scheme is presented, which yields a straightforward access to the minimum form of the flux equations and the occupation probability of the involved states in cyclic and linear reaction schemes. This is extremely simple for cyclic schemes without branches. If branches are involved, the effort of setting up the equations is a little bit higher. However, also here a straightforward recipe making use of so-called reserve factors is provided for implementing the branches into the cyclic scheme, thus enabling also a simple treatment of such cases. PMID:26646356

  2. Retinoic acid receptor signalling directly regulates osteoblast and adipocyte differentiation from mesenchymal progenitor cells

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

    Green, A.C.; Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Victoria 3065; Kocovski, P.

    Low and high serum retinol levels are associated with increased fracture risk and poor bone health. We recently showed retinoic acid receptors (RARs) are negative regulators of osteoclastogenesis. Here we show RARs are also negative regulators of osteoblast and adipocyte differentiation. The pan-RAR agonist, all-trans retinoic acid (ATRA), directly inhibited differentiation and mineralisation of early osteoprogenitors and impaired the differentiation of more mature osteoblast populations. In contrast, the pan-RAR antagonist, IRX4310, accelerated differentiation of early osteoprogenitors. These effects predominantly occurred via RARγ and were further enhanced by an RARα agonist or antagonist, respectively. RAR agonists similarly impaired adipogenesis in osteogenicmore » cultures. RAR agonist treatment resulted in significant upregulation of the Wnt antagonist, Sfrp4. This accompanied reduced nuclear and cytosolic β-catenin protein and reduced expression of the Wnt target gene Axin2, suggesting impaired Wnt/β-catenin signalling. To determine the effect of RAR inhibition in post-natal mice, IRX4310 was administered to male mice for 10 days and bones were assessed by µCT. No change to trabecular bone volume was observed, however, radial bone growth was impaired. These studies show RARs directly influence osteoblast and adipocyte formation from mesenchymal cells, and inhibition of RAR signalling in vivo impairs radial bone growth in post-natal mice. - Graphical abstract: Schematic shows RAR ligand regulation of osteoblast differentiation in vitro. RARγ antagonists±RARα antagonists promote osteoblast differentiation. RARγ and RARα agonists alone or in combination block osteoblast differentiation, which correlates with upregulation of Sfrp4, and downregulation of nuclear and cytosolic β-catenin and reduced expression of the Wnt target gene Axin2. Red arrows indicate effects of RAR agonists on mediators of Wnt signalling.« less

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

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

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

    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, secondarymore » 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.« less

  4. Retrospective comparison of mechanical percutaneous thrombectomy of hemodialysis arteriovenous grafts with the Arrow-Trerotola device and the lyse and wait technique.

    PubMed

    Vashchenko, Natalia; Korzets, Asher; Neiman, Chaim; Bachar, Gil N; Ori, Yaacov; Belenky, Alexander; Atar, Eli

    2010-06-01

    The purpose of our study was to determine whether pharmacologic thrombolysis with urokinase in the lyse and wait (L&W) technique compared with mechanical declotting using the Arrow-Trerotola percutaneous thrombectomy device is more efficient, safer, or less expensive in treating thrombosed hemodialysis grafts. The files of 157 patients who underwent arteriovenous graft declotting from 2000 to 2007 at one tertiary care center were reviewed. The study group included 83 women and 74 men with a mean age of 68 +/- 12 years (range, 27-95 years). A total of 563 procedures were performed: 427 with the L&W technique and 136 with mechanical percutaneous thrombectomy using the percutaneous thrombectomy device. The two types of procedures were compared for success rate, complications, average patency time, and cost. There were no statistically significant differences between the pharmacologic and mechanical procedures in immediate success rate (99% and 98%, respectively) or average patency time (5.44 months and 5.40 months, respectively). The L&W technique was considerably less expensive. Given its lower cost and equal efficacy and safety, L&W appears to be preferable to mechanical thrombolysis with a percutaneous thrombectomy device for initial arteriovenous hemodialysis graft declotting.

  5. ICA-Based Imagined Conceptual Words Classification on EEG Signals.

    PubMed

    Imani, Ehsan; Pourmohammad, Ali; Bagheri, Mahsa; Mobasheri, Vida

    2017-01-01

    Independent component analysis (ICA) has been used for detecting and removing the eye artifacts conventionally. However, in this research, it was used not only for detecting the eye artifacts, but also for detecting the brain-produced signals of two conceptual danger and information category words. In this cross-sectional research, electroencephalography (EEG) signals were recorded using Micromed and 19-channel helmet devices in unipolar mode, wherein Cz electrode was selected as the reference electrode. In the first part of this research, the statistical community test case included four men and four women, who were 25-30 years old. In the designed task, three groups of traffic signs were considered, in which two groups referred to the concept of danger, and the third one referred to the concept of information. In the second part, the three volunteers, two men and one woman, who had the best results, were chosen from among eight participants. In the second designed task, direction arrows (up, down, left, and right) were used. For the 2/8 volunteers in the rest times, very high-power alpha waves were observed from the back of the head; however, in the thinking times, they were different. According to this result, alpha waves for changing the task from thinking to rest condition took at least 3 s for the two volunteers, and it was at most 5 s until they went to the absolute rest condition. For the 7/8 volunteers, the danger and information signals were well classified; these differences for the 5/8 volunteers were observed in the right hemisphere, and, for the other three volunteers, the differences were observed in the left hemisphere. For the second task, simulations showed that the best classification accuracies resulted when the time window was 2.5 s. In addition, it also showed that the features of the autoregressive (AR)-15 model coefficients were the best choices for extracting the features. For all the states of neural network except hardlim discriminator

  6. 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.

  7. Working Memory Capacity in a Go/No-Go Task: Age Differences in Interference, Processing Speed, and Attentional Control

    ERIC Educational Resources Information Center

    Rodríguez-Villagra, Odir Antonio; Göthe, Katrin; Oberauer, Klaus; Kliegl, Reinhold

    2013-01-01

    We tested the limits of working-memory capacity (WMC) of young adults, old adults, and children with a memory-updating task. The task consisted of mentally shifting spatial positions within a grid according to arrows, their color signaling either only go (control) or go/no-go conditions. The interference model (IM) of Oberauer and Kliegl (2006)…

  8. NMR, MRI, and spectroscopic MRI in inhomogeneous fields

    DOEpatents

    Demas, Vasiliki; Pines, Alexander; Martin, Rachel W; Franck, John; Reimer, Jeffrey A

    2013-12-24

    A method for locally creating effectively homogeneous or "clean" magnetic field gradients (of high uniformity) for imaging (with NMR, MRI, or spectroscopic MRI) both in in-situ and ex-situ systems with high degrees of inhomogeneous field strength. THe method of imaging comprises: a) providing a functional approximation of an inhomogeneous static magnetic field strength B.sub.0({right arrow over (r)}) at a spatial position {right arrow over (r)}; b) providing a temporal functional approximation of {right arrow over (G)}.sub.shim(t) with i basis functions and j variables for each basis function, resulting in v.sub.ij variables; c) providing a measured value .OMEGA., which is an temporally accumulated dephasing due to the inhomogeneities of B.sub.0({right arrow over(r)}); and d) minimizing a difference in the local dephasing angle .phi.({right arrow over (r)},t)=.gamma..intg..sub.0.sup.t{square root over (|{right arrow over (B)}.sub.1({right arrow over (r)},t')|.sup.2+({right arrow over (r)}{right arrow over (G)}.sub.shimG.sub.shim(t')+.parallel.{right arrow over (B)}.sub.0({right arrow over (r)}).parallel..DELTA..omega.({right arrow over (r)},t'/.gamma/).sup.2)}dt'-.OMEGA. by varying the v.sub.ij variables to form a set of minimized v.sub.ij variables. The method requires calibration of the static fields prior to minimization, but may thereafter be implemented without such calibration, may be used in open or closed systems, and potentially portable systems.

  9. Can Neuroscience Help Us Do a Better Job of Teaching Music?

    ERIC Educational Resources Information Center

    Hodges, Donald A.

    2010-01-01

    We are just at the beginning stages of applying neuroscientific findings to music teaching. A simple model of the learning cycle based on neuroscience is Sense [right arrow] Integrate [right arrow] Act (sometimes modified as Act [right arrow] Sense [right arrow] Integrate). Additional components can be added to the model, including such concepts…

  10. Continental Shelf Embayments of the Eastern Margin of the Philippines; Lamon Bay Stratification & Circulation

    DTIC Science & Technology

    2012-09-30

    Philippines; Lamon Bay Stratification & Circulation Arnold L. Gordon Lamont-Doherty Earth Observatory 61 Route 9W Palisades , NY 10964-8000...AND ADDRESS(ES) Lamont-Doherty Earth Observatory,61 Route 9W, Palisades ,NY,10964-8000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING...recirculation cell has retreated northward. 7 Figure 5. Solid arrows denote stronger flow, with clear T/S source water signal. LB02 Kuroshio

  11. Top-down suppression of incompatible motor activations during response selection under conflict.

    PubMed

    Klein, Pierre-Alexandre; Petitjean, Charlotte; Olivier, Etienne; Duque, Julie

    2014-02-01

    Top-down control is critical to select goal-directed actions in changeable environments, particularly when several options compete for selection. This control system is thought to involve a mechanism that suppresses activation of unwanted response representations. We tested this hypothesis, in humans, by measuring motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) in a left finger muscle during motor preparation in an adapted Eriksen flanker task. Subjects reported, by a left or right button-press, the orientation of a left- or right-facing central arrow, flanked by two distractor arrows on each side. Central and peripheral arrows either pointed in the same (congruent trial) or in the opposite direction (incongruent trial). Top-down control was manipulated by changing the probability of congruent and incongruent trials in a given block. In the "mostly incongruent" (MI) blocks, 80% of trials were incongruent, producing a context in which subjects strongly anticipated that they would have to face conflict. In the "mostly congruent" (MC) blocks, 80% of trials were congruent and thus subjects barely anticipated conflict in that context. Thus, we assume that top-down control was stronger in the MI than in the MC condition. Accordingly, subjects displayed a lower error rate and shorter reaction times for the incongruent trials in the MI context than for similar trials in the MC context. More interestingly, we found that top-down control specifically reduced activation of the incompatible motor representation during response selection under high conflict. That is, when the central arrow specified a right hand response, left (non-selected) MEPs became smaller in the MI than in the MC condition, but only for incongruent trials, and this measure was positively correlated with performance. In contrast, MEPs elicited in the non-selected hand during congruent trials, or during all trials in which the left hand was selected, tended to increase

  12. How different location modes influence responses in a Simon-like task.

    PubMed

    Luo, Chunming; Proctor, Robert W

    2017-11-01

    Spatial information can be conveyed not only by stimulus position but by the meaning of a location word or direction of an arrow. We examined whether all the location-, arrow- and word-based Simon effects or some of them can be observed when a location word or an arrow is presented eccentrically and a left-right keypress is made to indicate its ink color. Results showed that only the location-based Simon effect was observed for location words, whereas an additional smaller arrow-based Simon effect, compared to the location-based Simon effect was observed, for arrows. These results showed spatial location, arrow direction, and location word stimulus dimensions affect response position codes in a spatial-to-verbal priority order, consistent with the possibility that they can activate mode-specific spatial representations.

  13. Singlet Fission's Two-for-One Potential - Continuum Magazine | NREL

    Science.gov Websites

    small arrows (one points up, the other down) on lower line labeled S0. For Panel b, left half has wavy red line angling in from left side; one short arrow points down on lower line, one short arrow points half of Panel a. For Panel c, left half, one small arrow points down on lower line and another points

  14. Army Communicator. Volume 36, Number 1, Spring 2011

    DTIC Science & Technology

    2011-01-01

    Contents Voice of the Signal Regiment Art Director/Illustrator Billy Cheney Photography Billy Cheney, Larry Edmond Cover: Warrant officers come from...standing on two arrows, which symbolize the military arts and sciences. The eagle rising is enclosed within a wreath. Warrant officers of the Tank...255A MOS are not knowledge managers. Our 255A are techni- cal officers who operate in the art , skill, and physical realm. They use practical

  15. Study of the hadronic decays of {chi}{sub c} states

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

    Bai, J.Z.; Bian, J.G.; Chen, G.P.

    1999-10-01

    Hadronic decays of the {ital P}-wave spin-triplet charmonium states {chi}{sub cJ}(J=0,1,2) are studied using a sample of {psi}(2S) decays collected by the BES detector operating at the BEPC storage ring. Branching fractions for the decays {chi}{sub c1}{r_arrow}K{sub S}{sup 0}K{sup +}{pi}{sup {minus}}+c.c., {chi}{sub c0}{r_arrow}K{sub S}{sup 0}K{sub S}{sup 0}, {chi}{sub c2}{r_arrow}K{sub S}{sup 0}K{sub S}{sup 0}, {chi}{sub c0}{r_arrow}{phi}{phi}, {chi}{sub c2}{r_arrow}{phi}{phi} and {chi}{sub cJ}{r_arrow}K{sup +}K{sup {minus}}K{sup +}K{sup {minus}} are measured for the first time, and those for {chi}{sub cJ}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{pi}{sup +}{pi}{sup {minus}}, {chi}{sub cJ}{r_arrow}{pi}{sup +}{pi}{sup {minus}}K{sup +}K{sup {minus}}, {chi}{sub cJ}{r_arrow}{pi}{sup +}{pi}{sup {minus}}p{bar p} and {chi}{sub cJ}{r_arrow}3({pi}{sup +}{pi}{sup {minus}}) are measured with improved precision.more » In addition, we determine the masses of the {chi}{sub c0} and {eta}{sub c} to be M{sub {chi}{sub c0}}=3414.1{plus_minus}0.6(stat){plus_minus}0.8(syst) MeV and M{sub {eta}{sub c}}=2975.8{plus_minus}3.9(stat){plus_minus}1.2(syst) MeV. {copyright} {ital 1999} {ital The American Physical Society}« less

  16. Strobe Traffic Lights Warn of Approaching Emergency Vehicles

    NASA Technical Reports Server (NTRS)

    Bachelder, Aaron

    2004-01-01

    Strobe-enhanced traffic signals have been developed to aid in the preemption of road intersections for emergency vehicles. The strobe-enhanced traffic signals can be incorporated into both new and pre-existing traffic-control systems in which the traffic-signal heads are of a relatively new type based on arrays of light-emitting diodes (LEDs). The strobe-enhanced traffic signals offer a less expensive, less complex alternative to a recently developed system of LED-based warning signs placed next to traffic signals. Because of its visual complexity, the combination of traffic signals and warning signs is potentially confusing to motorists. The strobe-enhanced traffic signals present less visual clutter. In a given traffic-signal head, the strobe-enhanced traffic signal is embedded in the red LED array of the stop signal. Two strobe LED strips one horizontal and one vertical are made capable of operating separately from the rest of the red LED matrix. When no emergency vehicle is approaching, the red LED array functions as a normal stop signal: all the red LEDs are turned on and off together. When the intersection is to be preempted for an approaching emergency vehicle, only the LEDs in one of the strobe strips are lit, and are turned on in a sequence that indicates the direction of approach. For example (see figure), if an emergency vehicle approaches from the right, the strobe LEDs are lit in a sequence moving from right to left. Important to the success of strobe-enhanced traffic signals is conformance to city ordinances and close relation to pre-existing traffic standards. For instance, one key restriction is that new icons must not include arrows, so that motorists will not confuse new icons with conventional arrows that indicate allowed directions of movement. It is also critical that new displays like strobe-enhanced traffic signals be similar to displays used in traffic-control systems in large cities. For example, Charleston, South Carolina uses horizontal

  17. Unconscious and out of control: subliminal priming is insensitive to observer expectations.

    PubMed

    Cressman, Erin K; Lam, Melanie Y; Franks, Ian M; Enns, James T; Chua, Romeo

    2013-09-01

    We asked whether the influence of an invisible prime on movement is dependent on conscious movement expectations. Participants reached to a central target, which triggered a directional prime-mask arrow sequence. Participants were instructed that the visible arrows (masks) would most often signal a movement modification in a specific (biased) direction. Kinematic analyses revealed that responses to the visible mask were influenced by participants' intentional bias, as movements were fastest when the more probable mask was displayed. In addition, responses were influenced by the invisible prime without regard to its relationship to the more probable mask. Analysis of the time of initial trajectory modifications revealed that both primes influenced responses in a similar manner after accounting for participants' bias. These results imply that invisible stimuli automatically activate their associated responses and that unconscious priming of the motor system is insensitive to the conscious expectations of the participant making the pointing movements. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Impaired reflexive orienting to social cues in attention deficit hyperactivity disorder.

    PubMed

    Marotta, Andrea; Casagrande, Maria; Rosa, Caterina; Maccari, Lisa; Berloco, Bianca; Pasini, Augusto

    2014-08-01

    The present study investigated whether another person's social attention, specifically the direction of their eye gaze, and non-social directional cues triggered reflexive orienting in individuals with Attention Deficit Hyperactivity Disorder (ADHD) and age-matched controls. A choice reaction time and a detection tasks were used in which eye gaze, arrow and peripheral cues correctly (congruent) or incorrectly (incongruent) signalled target location. Independently of the type of the task, differences between groups were specific to the cue condition. Typically developing individuals shifted attention to the location cued by both social and non-social cues, whereas ADHD group showed evidence of reflexive orienting only to locations previously cued by non-social stimuli (arrow and peripheral cues) but failed to show such orienting effect in response to social eye gaze cues. The absence of reflexive orienting effect for eye gaze cues observed in the participants with ADHD may reflect an attentional impairment in responding to socially relevant information.

  19. Measurement of the angular distribution of the electron from W {r_arrow} e = {nu} decay, in p pbar at {radical}s = 1.8 TeV, as function of P{sub T}{sup W}

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

    NONE

    1996-06-01

    The goal of this work is to study the behavior of the angular distribution of the electron from the decay of the W boson in a specific rest frame of the W, the Collins-Soper frame. More specifically, the parameter {alpha}{sub 2} from the expression d{sigma}/d(P{sub T}{sup W}){sup 2} d cos {theta}* = k(1 + {alpha}{sub 2} cos {theta}* + {alpha}{sup 2}(cos {theta}*){sup 2}), corresponding to the distribution of cos {theta}* in the Collins-Soper frame, was measured. The experimental value of {alpha}P{sub 2} was compared with the predictions made by E. Mirkes [11] who included the radiative QCD perturbations in themore » weak-interaction B{sub boson} {r_arrow} lepton + lepton. This experimental value was extracted for the first time using knowledge about how the radiative QCD perturbations will modify the predictions given by the Electro-Weak process only.« less

  20. 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.

  1. Recovering a full dimensional quantum rate constant from a reduced dimensionality calculation: Application to the OH+CO{r_arrow}H+CO{sub 2} reaction

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

    Dzegilenko, F.N.; Bowman, J.M.

    1996-08-01

    Two reduced dimensionality theories are used to calculate the thermal rate constant for the OH+CO{r_arrow}H+CO{sub 2} reaction. The standard theory employs energy-shift approximations to extract the full six degree-of-freedom quantum rate constant for this reaction from the previous two degree-of-freedom (2-DOF) quantum calculations of Hernandez and Clary [M.I. Hernandez and D.C. Clary, J. Chem. Phys. {bold 101}, 2779 (1994)]. Three extra bending modes and one extra {open_quote}{open_quote}spectator{close_quote}{close_quote} CO stretch mode are treated adiabatically in the harmonic fashion. The parameters of the exit channel transition state are used to evaluate the frequencies of those additional modes. A new reduced dimensionality theorymore » is also applied to this reaction. This theory explicitly addresses the finding from the 2-DOF calculations that the reaction proceeds mainly via complex formation. A J-shifting approximation has been used to take into account the initial states with non-zero values of total angular momentum in both reduced dimensionality theories. Cumulative reaction probabilities and thermal rate constants are calculated and compared with the previous quasiclassical and reduced dimensionality quantum calculations and with experiment. The rate constant from the new reduced dimensionality theory is between a factor of 5 and 100 times smaller than the statistical transition state theory result, and is in much better agreement with experiment. {copyright} {ital 1996 American Institute of Physics.}« less

  2. Author Correction: Induced unconventional superconductivity on the surface states of Bi2Te3 topological insulator.

    PubMed

    Charpentier, Sophie; Galletti, Luca; Kunakova, Gunta; Arpaia, Riccardo; Song, Yuxin; Baghdadi, Reza; Wang, Shu Min; Kalaboukhov, Alexei; Olsson, Eva; Tafuri, Francesco; Golubev, Dmitry; Linder, Jacob; Bauch, Thilo; Lombardi, Floriana

    2018-01-30

    The original version of this Article contained an error in Fig. 6b. In the top scattering process, while the positioning of both arrows was correct, the colours were switched: the first arrow was red and the second arrow was blue, rather than the correct order of blue then red.

  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. Syndromal frontonasal dysostosis in a child with a complex translocation involving chromosomes 3, 7, and 11

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

    Stevens, C.A.; Qumsiyeh, M.B.

    We report on a 4-year-old boy with typical frontonasal dysostosis and an apparently balanced de novo translocation involving chromosomes 3, 7, and 11, and four breakpoints. The karyotype was 46,XY,t(7;3)(3;11) (7pter{r_arrow}7q21.3::3q27{r_arrow}3qter;3pter{r_arrow}3q23::11q21{r_arrow}11qter;11pter{r_arrow}11q21::3q23{r_arrow}3q27::7q21.3{r_arrow}7qter). In situ hybridization with a chromosome 3 painting probe confirmed the interpretation from GTG banding. The child had a widow`s peak, marked hypertelorism, absence of the nasal tip, and widely separated nares. He also had an atrial septal defect, micropenis, small testes, clubfeet, scoliosis, block C2-4, and structural brain abnormalities on MRI. In review we found two other cases of frontonasal dysostosis with chromosome abnormalities, neither of which wasmore » similar to our case. The presence of a de novo (apparently) balanced translocation in our patient may help to locate the gene(s) for frontonasal dysplasia and perhaps other midline craniofacial malformations. 16 refs., 4 figs.« less

  5. Electrocardiographic characteristics in angiographically documented occlusion of the dominant left circumflex artery with acute inferior myocardial infarction: limitations of ST elevation III/II ratio and ST deviation in lateral limb leads.

    PubMed

    Zhan, Zhong-qun; Wang, Wei; Dang, Shu-yi; Wang, Chong-quan; Wang, Jun-feng; Cao, Zheng

    2009-01-01

    The prognosis of dominant left circumflex artery (LCx) occlusion-related inferior acute myocardial infarction (AMI) patients is poor, but the electrocardiographic (ECG) characteristics of this AMI entity have not been described. One hundred thirty-five patients with first dominant right coronary artery (RCA) or dominant LCx-related inferior AMI were included. The characteristics of ECG obtained on admission for 55 patients with culprit lesions proximal to the first major right ventricular (RV) branch of dominant RCA (group proximal dominant RCA), 62 patients with culprit lesions distal to the first major RV branch of dominant RCA (group distal dominant RCA), and 18 patients with culprit lesions in dominant LCx (group dominant LCx) were compared. There were no significant differences among the 3 groups in the prevalence regarding an S/R ratio greater than 1:3 in aVL, ST elevation in aVR (ST upward arrow(aVR)), ST depression in aVR (ST downward arrow(aVR)) of 1 mm or more, and atrioventricular block. Greater ST elevation in lead III than in II and greater ST depression in aVL than I showed specificity of 17% and 44% to identify dominant RCA as culprit lesion, respectively. All 3 groups could be distinguished on the basis of ST upward arrow(V4R), ST downward arrow(V4R), ST downward arrow(V3)/ST upward arrow(III) of 1.2 or less, and ST downward arrow(V3)/ST upward arrow(III) of more than 1.2. Greater ST elevation in lead III than in II, greater ST depression in aVL than I, and an S/R ratio of greater than 1:3 in aVL were not useful to discriminate between dominant RCA and dominant LCx occlusion-related inferior AMI. ST-segment deviation in lead V(4)R and the ratio of ST downward arrow(V3)/ST upward arrow(III) were useful in predicting the dominant artery occlusion-related inferior AMI.

  6. Stop/Start: Driving

    Science.gov Websites

    /generator visible. The car is moving. There are purple arrows flowing from the gasoline engine to the electric starter/generator. There are red arrows flowing from the gasoline engine to the front wheels . There are blue arrows flowing from the electric starter/generator to the battery. Main stage: See

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

    Schuffenhauer, S.; Daumer-Haas, C.; Murken, J.

    Karyotypes with an interstitial deletion and a marker chromosome formed from the deleted segment are rare. We identified such a rearrangement in a newborn infant, who presented with macrocephaly, asymmetric square skull, minor facial anomalies, omphalocele, inguinal hernias, hypospadias, and club feet. The karyotype 46,XY,del(5)(pter{r_arrow}p13::cen{r_arrow}qter)/47,XY,+dicr(5)(:p13{r_arrow}cen::p13{r_arrow}cen),del(5)(pter{r_arrow}p13::cen{r_arrow}qter) was identified by banding studies and FISH analysis in the peripheral lymphocytes. One breakpoint on the del(5) maps distal to GDNF, and FISH analysis using an {alpha}-satellite probe suggests that the proximal breakpoint maps within the centromere. The dicentric r(5) consists of two copies of the segment deleted in the del(5), resulting in trisomy ofmore » proximal 5p (5p13-cen). The phenotype of the propositus is compared with other trisomy 5p cases and possible mechanisms for the generation of this unique chromosomal rearrangement are discussed. 27 refs., 3 figs.« less

  8. Thomas R. Cech, RNA, and Ribozymes

    Science.gov Websites

    RSS Archive Videos XML DOE R&D Accomplishments DOE R&D Accomplishments searchQuery × Find searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About Physicists Nobel Chemists Medicine Nobels Explore dropdown arrow Insights Blog Archive SC Stories Snapshots R

  9. DOE Research and Development Accomplishments: Visions of Success I

    Science.gov Websites

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  10. DOE Research and Development Accomplishments Contact Us

    Science.gov Websites

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  11. DOE Research and Development Accomplishments QR Code

    Science.gov Websites

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  12. DOE Research and Development Accomplishments What's New

    Science.gov Websites

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  13. DOE Research and Development Accomplishments: Fast Facts

    Science.gov Websites

    RSS Archive Videos XML DOE R&D Accomplishments DOE R&D Accomplishments searchQuery × Find searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About Physicists Nobel Chemists Medicine Nobels Explore dropdown arrow Insights Blog Archive SC Stories Snapshots R

  14. 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.

  15. Building the Information Superhighway

    Science.gov Websites

    the images are scanned into a computer frame by frame, which tracks and measures the changing shape of searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About dropdown arrow Site Map A-Z Index Menu Synopsis "Building the Information Superhighway" takes a

  16. Hill Ciphers over Near-Fields

    ERIC Educational Resources Information Center

    Farag, Mark

    2007-01-01

    Hill ciphers are linear codes that use as input a "plaintext" vector [p-right arrow above] of size n, which is encrypted with an invertible n x n matrix E to produce a "ciphertext" vector [c-right arrow above] = E [middle dot] [p-right arrow above]. Informally, a near-field is a triple [left angle bracket]N; +, *[right angle bracket] that…

  17. Memories of Reward and Nonreward Regulate the Extinction and Reacquisition of both Excitatory and Inhibitory Associations

    ERIC Educational Resources Information Center

    Capaldi, E. J.; Martins, Ana P. G.; Altman, Meaghan

    2009-01-01

    arrow]US associations also survived The memories of the unconditioned stimulus (US) and its absence (No US), symbolized as S[superscript R] and S[superscript N], respectively, may be retrieved on US or No US trials giving rise to four types of associations, S[superscript R][right arrow]US, S[superscript R][right arrow]No US, S[superscript N][right…

  18. Hybrid: Cruising

    Science.gov Websites

    battery, engine, and electric motor visible. The car is moving. There are red arrows flowing from the gasoline engine to the front wheels. There are blue arrows flowing from the gasoline engine to the electric car is moving. There are red arrows flowing from the gasoline engine to the front wheels. There are

  19. Adding signals to coordinated traffic signal systems.

    DOT National Transportation Integrated Search

    1983-08-01

    The purpose of this research was to investigate the effect of adding or : removing traffic signals within a coordinated, signal-controlled street network. : The report includes a discussion of coordinated signal systems; arterial street : network con...

  20. 29 CFR 1926.1422 - Signals-hand signal chart.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Signals-hand signal chart. 1926.1422 Section 1926.1422 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Construction § 1926.1422 Signals—hand signal chart. Hand signal charts must be either posted on the equipment...

  1. 29 CFR 1926.1422 - Signals-hand signal chart.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Signals-hand signal chart. 1926.1422 Section 1926.1422 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Construction § 1926.1422 Signals—hand signal chart. Hand signal charts must be either posted on the equipment...

  2. 29 CFR 1926.1422 - Signals-hand signal chart.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Signals-hand signal chart. 1926.1422 Section 1926.1422 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Construction § 1926.1422 Signals—hand signal chart. Hand signal charts must be either posted on the equipment...

  3. Males adjust their signalling behaviour according to experience of male signals and male-female signal duets.

    PubMed

    Rebar, D; Rodríguez, R L

    2016-04-01

    Sexual signals are conspicuous sources of information about neighbouring competitors, and species in which males and females signal during pair formation provide various sources of public information to which individuals can adjust their behaviour. We performed two experiments with a duetting vibrational insect, Enchenopa binotata treehoppers (Hemiptera: Membracidae), to ask whether males adjust their signalling behaviour according to (1a) their own experience of competitors' signals, (1b) how females adjust their mate preferences on the basis of their experience of male signals (described in prior work), and/or (2) their own experience of female response signals to competitors' signals. We presented males with synthetic male signals of different frequencies and combinations thereof for 2 weeks. We recorded males a day after their last signal exposure, finding that (1a) male signal rate increased in response to experience of attractive competitors, but that (1b) male signal frequency did not shift in a manner consistent with how females adjust their mate preferences in those experience treatments. Second, we presented males with different male-female duets for 2 weeks, finding that (2) male signal length increased from experience of female duets with attractive competitors. Males thus make two types of adjustment according to two sources of public information: one provided by experience of male signals and another by experience of female responses to male signals. Signalling plasticity can generate feedback loops between the adjustments that males and females make, and we discuss the potential consequences of such feedback loops for the evolution of communication systems. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  4. 49 CFR 236.310 - Signal governing approach to home signal.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Signal governing approach to home signal. 236.310... Standards § 236.310 Signal governing approach to home signal. A signal shall be provided on main track to govern the approach with the current of traffic to any home signal except where the home signal is the...

  5. 49 CFR 236.310 - Signal governing approach to home signal.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Signal governing approach to home signal. 236.310... Standards § 236.310 Signal governing approach to home signal. A signal shall be provided on main track to govern the approach with the current of traffic to any home signal except where the home signal is the...

  6. 49 CFR 236.310 - Signal governing approach to home signal.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Signal governing approach to home signal. 236.310... Standards § 236.310 Signal governing approach to home signal. A signal shall be provided on main track to govern the approach with the current of traffic to any home signal except where the home signal is the...

  7. Signaling cascades modulate the speed of signal propagation through space.

    PubMed

    Govern, Christopher C; Chakraborty, Arup K

    2009-01-01

    Cells are not mixed bags of signaling molecules. As a consequence, signals must travel from their origin to distal locations. Much is understood about the purely diffusive propagation of signals through space. Many signals, however, propagate via signaling cascades. Here, we show that, depending on their kinetics, cascades speed up or slow down the propagation of signals through space, relative to pure diffusion. We modeled simple cascades operating under different limits of Michaelis-Menten kinetics using deterministic reaction-diffusion equations. Cascades operating far from enzyme saturation speed up signal propagation; the second mobile species moves more quickly than the first through space, on average. The enhanced speed is due to more efficient serial activation of a downstream signaling module (by the signaling molecule immediately upstream in the cascade) at points distal from the signaling origin, compared to locations closer to the source. Conversely, cascades operating under saturated kinetics, which exhibit zero-order ultrasensitivity, can slow down signals, ultimately localizing them to regions around the origin. Signal speed modulation may be a fundamental function of cascades, affecting the ability of signals to penetrate within a cell, to cross-react with other signals, and to activate distant targets. In particular, enhanced speeds provide a way to increase signal penetration into a cell without needing to flood the cell with large numbers of active signaling molecules; conversely, diminished speeds in zero-order ultrasensitive cascades facilitate strong, but localized, signaling.

  8. Scram signal generator

    DOEpatents

    Johanson, Edward W.; Simms, Richard

    1981-01-01

    A scram signal generating circuit for nuclear reactor installations monitors a flow signal representing the flow rate of the liquid sodium coolant which is circulated through the reactor, and initiates reactor shutdown for a rapid variation in the flow signal, indicative of fuel motion. The scram signal generating circuit includes a long-term drift compensation circuit which processes the flow signal and generates an output signal representing the flow rate of the coolant. The output signal remains substantially unchanged for small variations in the flow signal, attributable to long term drift in the flow rate, but a rapid change in the flow signal, indicative of a fast flow variation, causes a corresponding change in the output signal. A comparator circuit compares the output signal with a reference signal, representing a given percentage of the steady state flow rate of the coolant, and generates a scram signal to initiate reactor shutdown when the output signal equals the reference signal.

  9. Scram signal generator

    DOEpatents

    Johanson, E.W.; Simms, R.

    A scram signal generating circuit for nuclear reactor installations monitors a flow signal representing the flow rate of the liquid sodium coolant which is circulated through the reactor, and initiates reactor shutdown for a rapid variation in the flow signal, indicative of fuel motion. The scram signal generating circuit includes a long-term drift compensation circuit which processes the flow signal and generates an output signal representing the flow rate of the coolant. The output signal remains substantially unchanged for small variations in the flow signal, attributable to long term drift in the flow rate, but a rapid change in the flow signal, indicative of a fast flow variation, causes a corresponding change in the output signal. A comparator circuit compares the output signal with a reference signal, representing a given percentage of the steady state flow rate of the coolant, and generates a scram signal to initiate reactor shutdown when the output signal equals the reference signal.

  10. Neuroblastoma in a boy with MCA/MR syndrome, deletion 11q, and duplication 12q

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

    Koiffmann, C.P.; Vianna-Morgante, A.M.; Wajntal, A.

    Deletion 11q23{r_arrow}qter and duplication 12q23{r_arrow}qter are described in a boy with neuroblastoma, multiple congenital anomalies, and mental retardation. The patient has clinical manifestations of 11q deletion and 12q duplication syndromes. The possible involvement of the segment 11q23{r_arrow}24 in the cause of the neuroblastoma is discussed. 18 refs., 2 figs., 1 tab.

  11. --No Title--

    Science.gov Websites

    { background-color: #000; color: #FFF; max-width: 200px; padding: 5px 8px 4px 8px; text-align: center ; }*/ .tipsy-inner { background-color: #f5f5f5; color: midnightblue; max-width: 200px; padding: 6px; text-align ; } /* Rules to colour arrows */ .tipsy-arrow-n { border-bottom-color: #000; } .tipsy-arrow-s { border-top

  12. 49 CFR 236.310 - Signal governing approach to home signal.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Signal governing approach to home signal. 236.310..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.310 Signal governing approach to home signal. A signal shall be provided on main track to...

  13. 49 CFR 236.310 - Signal governing approach to home signal.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Signal governing approach to home signal. 236.310..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.310 Signal governing approach to home signal. A signal shall be provided on main track to...

  14. Regulation of Hippo signalling by p38 signalling

    PubMed Central

    Huang, Dashun; Li, Xiaojiao; Sun, Li; Huang, Ping; Ying, Hao; Wang, Hui; Wu, Jiarui; Song, Haiyun

    2016-01-01

    The Hippo signalling pathway has a crucial role in growth control during development, and its dysregulation contributes to tumorigenesis. Recent studies uncover multiple upstream regulatory inputs into Hippo signalling, which affects phosphorylation of the transcriptional coactivator Yki/YAP/TAZ by Wts/Lats. Here we identify the p38 mitogen-activated protein kinase (MAPK) pathway as a new upstream branch of the Hippo pathway. In Drosophila, overexpression of MAPKK gene licorne (lic), or MAPKKK gene Mekk1, promotes Yki activity and induces Hippo target gene expression. Loss-of-function studies show that lic regulates Hippo signalling in ovary follicle cells and in the wing disc. Epistasis analysis indicates that Mekk1 and lic affect Hippo signalling via p38b and wts. We further demonstrate that the Mekk1-Lic-p38b cascade inhibits Hippo signalling by promoting F-actin accumulation and Jub phosphorylation. In addition, p38 signalling modulates actin filaments and Hippo signalling in parallel to small GTPases Ras, Rac1, and Rho1. Lastly, we show that p38 signalling regulates Hippo signalling in mammalian cell lines. The Lic homologue MKK3 promotes nuclear localization of YAP via the actin cytoskeleton. Upregulation or downregulation of the p38 pathway regulates YAP-mediated transcription. Our work thus reveals a conserved crosstalk between the p38 MAPK pathway and the Hippo pathway in growth regulation. PMID:27402810

  15. Mono-static GPR without transmitting anything for pavement damage inspection: interferometry by auto-correlation applied to mobile phone signals

    NASA Astrophysics Data System (ADS)

    Feld, R.; Slob, E. C.; Thorbecke, J.

    2015-12-01

    Creating virtual sources at locations where physical receivers have measured a response is known as seismic interferometry. A much appreciated benefit of interferometry is its independence of the actual source locations. The use of ambient noise as actual source is therefore not uncommon in this field. Ambient noise can be commercial noise, like for example mobile phone signals. For GPR this can be useful in cases where it is not possible to place a source, for instance when it is prohibited by laws and regulations. A mono-static GPR antenna can measure ambient noise. Interferometry by auto-correlation (AC) places a virtual source on this antenna's position, without actually transmitting anything. This can be used for pavement damage inspection. Earlier work showed very promising results with 2D numerical models of damaged pavement. 1D and 2D heterogeneities were compared, both modelled in a 2D pavement world. In a 1D heterogeneous model energy leaks away to the sides, whereas in a 2D heterogeneous model rays can reflect and therefore still add to the signal reconstruction (see illustration). In the first case the amount of stationary points is strictly limited, while in the other case the amount of stationary points is very large. We extend these models to a 3D world and optimise an experimental configuration. The illustration originates from the journal article under submission 'Non-destructive pavement damage inspection by mono-static GPR without transmitting anything' by R. Feld, E.C. Slob, and J.W. Thorbecke. (a) 2D heterogeneous pavement model with three irregular-shaped misalignments between the base and subbase layer (marked by arrows). Mono-antenna B-scan positions are shown schematically. (b) Ideal output: a real source at the receiver's position. The difference w.r.t. the trace found in the middle is shown. (c) AC output: a virtual source at the receiver's position. There is a clear overlap with the ideal output.

  16. Signaling aggression.

    PubMed

    van Staaden, Moira J; Searcy, William A; Hanlon, Roger T

    2011-01-01

    From psychological and sociological standpoints, aggression is regarded as intentional behavior aimed at inflicting pain and manifested by hostility and attacking behaviors. In contrast, biologists define aggression as behavior associated with attack or escalation toward attack, omitting any stipulation about intentions and goals. Certain animal signals are strongly associated with escalation toward attack and have the same function as physical attack in intimidating opponents and winning contests, and ethologists therefore consider them an integral part of aggressive behavior. Aggressive signals have been molded by evolution to make them ever more effective in mediating interactions between the contestants. Early theoretical analyses of aggressive signaling suggested that signals could never be honest about fighting ability or aggressive intentions because weak individuals would exaggerate such signals whenever they were effective in influencing the behavior of opponents. More recent game theory models, however, demonstrate that given the right costs and constraints, aggressive signals are both reliable about strength and intentions and effective in influencing contest outcomes. Here, we review the role of signaling in lieu of physical violence, considering threat displays from an ethological perspective as an adaptive outcome of evolutionary selection pressures. Fighting prowess is conveyed by performance signals whose production is constrained by physical ability and thus limited to just some individuals, whereas aggressive intent is encoded in strategic signals that all signalers are able to produce. We illustrate recent advances in the study of aggressive signaling with case studies of charismatic taxa that employ a range of sensory modalities, viz. visual and chemical signaling in cephalopod behavior, and indicators of aggressive intent in the territorial calls of songbirds. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Experimental Studies of the NaK 3^1Π and 1^3Δ States

    NASA Astrophysics Data System (ADS)

    Prodan, I. D.; Marks, A.; Sibbach, L.; Laub, E.; Mazsa, I.; Webb, S.; La Civita, J.; Galle, E.; Jabbour, Z. J.; Namiotka, R. K.; Morgus, T.; Huennekens, J.; Li, Li

    2000-06-01

    We report the results of optical-optical double resonance experiments designed to study the 3^1Π and 1^3Δ states of NaK. In the first step, a narrow band cw dye laser (PUMP) was tuned to excite a particular 2(A)^1Σ^+(v_A, J') level [or 2(A)^1Σ^+(v_A, J') ~ 1(b)^3Π(v_b, J') mixed level], and its frequency was then fixed. A second narrow band tunable cw Ti:Sapphire laser (PROBE) was then scanned over transitions to various 3^1Π(v_Π, J) [or 1^3Δ(v_Δ, J)] levels while 3^1Π arrow 1(X)^1Σ^+ violet fluorescence [or collision-induced ^3Λ arrow 1(a)^3Σ^+ green fluorescence] was monitored. The Doppler-free signals accurately map the 3^1Π and 1^3Δ state ro-vibrational energy levels. These energy levels were then fit to Dunham expansions to provide experimental molecular constants, allowing the construction of RKR potential curves that have been compared to recent theoretical calculations. Comparison between observed and calculated Franck-Condon factors was used to determine variation of the 3^1Πarrow1(X)^1Σ^+ transition dipole moment with internuclear separation. A deperturbation analysis of the 1^3Δ state was performed to determine the spin-orbit constant for that state. The 1^3Δ state hyperfine structure, due to the Fermi contact interaction between the electron spin and the sodium atom nuclear spin, was also studied.

  18. {pi} junction and spontaneous current state in a superfluid Fermi gas

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

    Kashimura, Takashi; Tsuchiya, Shunji; CREST

    2011-07-15

    We discuss an idea to realize a spontaneous current in a superfluid Fermi gas. When a polarized Fermi superfluid (N{sub {up_arrow}}>N{sub {down_arrow}}, where N{sub {sigma}} is the number of atoms in the hyperfine state described by pseudospin {sigma}={up_arrow},{down_arrow}) is loaded onto a ring-shaped trap with a weak potential barrier, some excess atoms ({Delta}N=N{sub {up_arrow}}-N{sub {down_arrow}}) are localized around the barrier. As shown in our previous paper [T. Kashimura, S. Tsuchiya, and Y. Ohashi, Phys. Rev. A 82, 033617 (2010)], this polarized potential barrier works as a {pi} junction in the sense that the superfluid order parameter changes its sign acrossmore » the barrier. Because of this, the phase of the superfluid order parameter outside the junction is shown to be twisted by {pi} along the ring, which naturally leads to a circulating supercurrent. While the ordinary supercurrent state is obtained as a metastable state, this spontaneous current state is shown to be more stable than the case with no current. Our results indicate that localized excess atoms would be useful for the manipulation of the superfluid order parameter in cold Fermi gases.« less

  19. Robust power detector for wideband signals among many single tone signals

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

    Musgrove, Cameron H.; Thompson, Douglas

    Various technologies for isolating a signal of interest from signals received contemporaneously by an antenna are described herein. A time period for which a signal of interest is present in a second signal can be identified based upon ratios of values of the second signal to the mean value of the second signal. When the ratio of the value of the second signal at a particular time to the mean of the second signal exceeds a threshold value, the signal of interest is considered to be present in the second signal.

  20. Regulation of Hippo signalling by p38 signalling.

    PubMed

    Huang, Dashun; Li, Xiaojiao; Sun, Li; Huang, Ping; Ying, Hao; Wang, Hui; Wu, Jiarui; Song, Haiyun

    2016-08-01

    The Hippo signalling pathway has a crucial role in growth control during development, and its dysregulation contributes to tumorigenesis. Recent studies uncover multiple upstream regulatory inputs into Hippo signalling, which affects phosphorylation of the transcriptional coactivator Yki/YAP/TAZ by Wts/Lats. Here we identify the p38 mitogen-activated protein kinase (MAPK) pathway as a new upstream branch of the Hippo pathway. In Drosophila, overexpression of MAPKK gene licorne (lic), or MAPKKK gene Mekk1, promotes Yki activity and induces Hippo target gene expression. Loss-of-function studies show that lic regulates Hippo signalling in ovary follicle cells and in the wing disc. Epistasis analysis indicates that Mekk1 and lic affect Hippo signalling via p38b and wts We further demonstrate that the Mekk1-Lic-p38b cascade inhibits Hippo signalling by promoting F-actin accumulation and Jub phosphorylation. In addition, p38 signalling modulates actin filaments and Hippo signalling in parallel to small GTPases Ras, Rac1, and Rho1. Lastly, we show that p38 signalling regulates Hippo signalling in mammalian cell lines. The Lic homologue MKK3 promotes nuclear localization of YAP via the actin cytoskeleton. Upregulation or downregulation of the p38 pathway regulates YAP-mediated transcription. Our work thus reveals a conserved crosstalk between the p38 MAPK pathway and the Hippo pathway in growth regulation. © The Author (2016). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS.

  1. Salicylic acid signaling inhibits apoplastic reactive oxygen species signaling.

    PubMed

    Xu, Enjun; Brosché, Mikael

    2014-06-04

    Reactive oxygen species (ROS) are used by plants as signaling molecules during stress and development. Given the amount of possible challenges a plant face from their environment, plants need to activate and prioritize between potentially conflicting defense signaling pathways. Until recently, most studies on signal interactions have focused on phytohormone interaction, such as the antagonistic relationship between salicylic acid (SA)-jasmonic acid and cytokinin-auxin. In this study, we report an antagonistic interaction between SA signaling and apoplastic ROS signaling. Treatment with ozone (O3) leads to a ROS burst in the apoplast and induces extensive changes in gene expression and elevation of defense hormones. However, Arabidopsis thaliana dnd1 (defense no death1) exhibited an attenuated response to O3. In addition, the dnd1 mutant displayed constitutive expression of defense genes and spontaneous cell death. To determine the exact process which blocks the apoplastic ROS signaling, double and triple mutants involved in various signaling pathway were generated in dnd1 background. Simultaneous elimination of SA-dependent and SA-independent signaling components from dnd1 restored its responsiveness to O3. Conversely, pre-treatment of plants with SA or using mutants that constitutively activate SA signaling led to an attenuation of changes in gene expression elicited by O3. Based upon these findings, we conclude that plants are able to prioritize the response between ROS and SA via an antagonistic action of SA and SA signaling on apoplastic ROS signaling.

  2. Salicylic acid signaling inhibits apoplastic reactive oxygen species signaling

    PubMed Central

    2014-01-01

    Background Reactive oxygen species (ROS) are used by plants as signaling molecules during stress and development. Given the amount of possible challenges a plant face from their environment, plants need to activate and prioritize between potentially conflicting defense signaling pathways. Until recently, most studies on signal interactions have focused on phytohormone interaction, such as the antagonistic relationship between salicylic acid (SA)-jasmonic acid and cytokinin-auxin. Results In this study, we report an antagonistic interaction between SA signaling and apoplastic ROS signaling. Treatment with ozone (O3) leads to a ROS burst in the apoplast and induces extensive changes in gene expression and elevation of defense hormones. However, Arabidopsis thaliana dnd1 (defense no death1) exhibited an attenuated response to O3. In addition, the dnd1 mutant displayed constitutive expression of defense genes and spontaneous cell death. To determine the exact process which blocks the apoplastic ROS signaling, double and triple mutants involved in various signaling pathway were generated in dnd1 background. Simultaneous elimination of SA-dependent and SA-independent signaling components from dnd1 restored its responsiveness to O3. Conversely, pre-treatment of plants with SA or using mutants that constitutively activate SA signaling led to an attenuation of changes in gene expression elicited by O3. Conclusions Based upon these findings, we conclude that plants are able to prioritize the response between ROS and SA via an antagonistic action of SA and SA signaling on apoplastic ROS signaling. PMID:24898702

  3. Role of Progesterone Receptor Isoforms in Regulation of Cell Adhesion and Apoptosis

    DTIC Science & Technology

    2002-06-01

    repeatable) (figure 1 below). We used taxol to induce apoptosis instead of tumor necrosis factor (TNF) (as initially proposed in the grant) because...highlighted in red in Fig. 6A), monocyte chemotactic protein (MCP; open arrow in Fig. 6A and isolated in Fig. 6B, top) and bullous pemphigoid antigen...red. The open arrow indicates monocyte chemotactic protein (MCP) and closed arrow indi- cates bullous pemphigoid antigen (BPAG). B, top, isolated

  4. Electrical resistivity of Co-Ni-Pd and Co-Pd alloys

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

    Jen, S.U.; Chen, T.P.; Chang, S.A.

    1991-11-15

    Three series of ferromagnetic alloys have been made: Co{sub 100{minus}{ital x}}Pd{sub {ital x}}, Co{sub 25}Ni{sub 75{minus}{ital y}}Pd{sub {ital y}} and Co{sub 5{minus}{ital z}}Ni{sub {ital z}}Pd{sub 95}. The electrical resistivity {rho} of these alloys was measured from 4 to 300 K. Their high field ({ital H}{gt}2 T) susceptibility {chi}{sub HF} was obtained with superconducting quantum interference device measurements at 5 K. Comparing the residual resistivity {rho}{sub 0} of Co-Ni and Co-Pd, it is found that the spin-up resistivity {rho}{sub {up arrow}} of Co-Ni follows the Nordheim's rule, while that of Co-Pd peaks at {ital x}=85. This indicates the spin-up {ital d}more » band of Co-Pd is not full for all the {ital x} values. Also, {chi}{sub HF} data reveal the same tendency of the spin-up band. Based on the deviation from Matthiessen's rule of the two-current model, we estimate {alpha}={rho}{sub 0{down arrow}} /{rho}{sub 0{up arrow}}{congruent}2 for the dilute {ital PdCo} alloy, where {rho}{sub 0}={rho}{sub 0{down arrow}} {rho}{sub 0{up arrow}}/({rho}{sub 0{up arrow}}+{rho}{sub 0{down arrow}} ), from the residual resistivity of the ternary Co{sub 5{minus}{ital z}}Ni{sub {ital z}}Pd{sub 95} alloy and from the temperature dependence of {rho}({ital T}) of the binary Co{sub 5}Pd{sub 95} alloy« less

  5. Optofluidic devices for biomolecule sensing and multiplexing

    NASA Astrophysics Data System (ADS)

    Ozcelik, Damla

    Optofluidics which integrates photonics and microfluidics, has led to highly compact, sensitive and adaptable biomedical sensors. Optofluidic biosensors based on liquid-core anti-resonant reflecting optical waveguides (LC-ARROWs), have proven to be a highly sensitive, portable, and reconfigurable platform for fluorescence spectroscopy and detection of single biomolecules such as proteins, nucleic acids, and virus particles. However, continued improvements in sensitivity remain a major goal as we approach the ultimate limit of detecting individual bio-particles labeled by single or few fluorophores. Additionally, the ability to simultaneously detect and identify multiple biological particles or biomarkers is one of the key requirements for molecular diagnostic tests. The compactness and adaptability of these platforms can further be advanced by introducing tunability, integrating off-chip components, designing reconfigurable and customizable devices, which makes these platforms very good candidates for many different applications. The goal of this thesis was to introduce new elements in these LC-ARROW optofluidics platforms that provide major enhancements in their functionality, making them more sensitive, compact, customizable and multiplexed. First, a novel integrated tunable spectral filter that achieves effective elimination of background noise on the ARROW platform was demonstrated. A unique dual liquid-core design enabled the independent multi-wavelength tuning of the spectral filter by adjusting the refractive index and chemical properties of the liquid. In order to enhance the detection sensitivity of the platform, Y-splitter waveguides were integrated to create multiple excitation spots for each target molecule. A powerful signal processing algorithm was used to analyze the data to improve the signal-to-noise ratio (SNR) of the collected data. Next, the design, optimization and characterization of the Y-splitter waveguides are presented; and single

  6. Reviews Toy: Air swimmers Book: Their Arrows will Darken the Sun: The Evolution and Science of Ballistics Book: Physics Experiments for your Bag Book: Quantum Physics for Poets Equipment: SEP colour wheel kit Equipment: SEP colour mixing kit Software: USB DrDAQ App: iHandy Level Equipment: Photonics Explorer kit Web Watch

    NASA Astrophysics Data System (ADS)

    2012-01-01

    WE RECOMMEND Air swimmers Helium balloon swims like a fish Their Arrows will Darken the Sun: The Evolution and Science of Ballistics Ballistics book hits the spot Physics Experiments for your Bag Handy experiments for your lessons Quantum Physics for Poets Book shows the economic importance of physics SEP colour wheel kit Wheels investigate colour theory SEP colour mixing kit Cheap colour mixing kit uses red, green and blue LEDs iHandy Level iPhone app superbly measures angles Photonics Explorer kit Free optics kit given to schools WORTH A LOOK DrDAQ DrDAQ software gets an upgrade WEB WATCH Websites show range of physics

  7. FijiWingsPolarity: An open source toolkit for semi-automated detection of cell polarity.

    PubMed

    Dobens, Leonard L; Shipman, Anna; Axelrod, Jeffrey D

    2018-01-02

    Epithelial cells are defined by apical-basal and planar cell polarity (PCP) signaling, the latter of which establishes an orthogonal plane of polarity in the epithelial sheet. PCP signaling is required for normal cell migration, differentiation, stem cell generation and tissue repair, and defects in PCP have been associated with developmental abnormalities, neuropathologies and cancers. While the molecular mechanism of PCP is incompletely understood, the deepest insights have come from Drosophila, where PCP is manifest in hairs and bristles across the adult cuticle and organization of the ommatidia in the eye. Fly wing cells are marked by actin-rich trichome structures produced at the distal edge of each cell in the developing wing epithelium and in a mature wing the trichomes orient collectively in the distal direction. Genetic screens have identified key PCP signaling pathway components that disrupt trichome orientation, which has been measured manually in a tedious and error prone process. Here we describe a set of image processing and pattern-recognition macros that can quantify trichome arrangements in micrographs and mark these directly by color, arrow or colored arrow to indicate trichome location, length and orientation. Nearest neighbor calculations are made to exploit local differences in orientation to better and more reliably detect and highlight local defects in trichome polarity. We demonstrate the use of these tools on trichomes in adult wing preps and on actin-rich developing trichomes in pupal wing epithelia stained with phalloidin. FijiWingsPolarity is freely available and will be of interest to a broad community of fly geneticists studying the effect of gene function on PCP.

  8. Design and analysis of a silicon-based antiresonant reflecting optical waveguide chemical sensor

    NASA Astrophysics Data System (ADS)

    Remley, Kate A.; Weisshaar, Andreas

    1996-08-01

    The design of a silicon-based antiresonant reflecting optical waveguide (ARROW) chemical sensor is presented, and its theoretical performance is compared with that of a conventional structure. The use of an ARROW structure permits incorporation of a thick guiding region for efficient coupling to a single-mode fiber. A high-index overlay is added to fine tune the sensitivity of the ARROW chemical sensor. The sensitivity of the sensor is presented, and design trade-offs are discussed.

  9. ACHP | ACHP Native American Program: Guidance for Federal Agencies

    Science.gov Websites

    Working with Section 106 Federal, State, & Tribal Programs Training & Education Publications Search skip specific nav links Home arrow Working with Section 106 arrow ACHP Native American Program

  10. 26 CFR 48.4161(b)-2 - Meaning of terms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... arrows are arrow shafts, nocks, tips, heads, head adapters, and feathers. (2) General purpose materials... general purpose materials or articles are glues and cements, feathers before they are prepared for use...

  11. 26 CFR 48.4161(b)-2 - Meaning of terms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... arrows are arrow shafts, nocks, tips, heads, head adapters, and feathers. (2) General purpose materials... general purpose materials or articles are glues and cements, feathers before they are prepared for use...

  12. Superfluid-ferromagnet-superfluid junction and the {pi} phase in a superfluid Fermi gas

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

    Kashimura, Takashi; Tsuchiya, Shunji; CREST

    2010-09-15

    We investigate the possibility of a superfluid-ferromagnet-superfluid (SFS) junction in a superfluid Fermi gas. To examine this possibility in a simple manner, we consider an attractive Hubbard model at T=0 within the mean-field theory. When a potential barrier is embedded in a superfluid Fermi gas with population imbalance (N{sub {up_arrow}}>N{sub {down_arrow}}, where N{sub {sigma}} is the number of atoms with pseudospin {sigma}= {up_arrow}, {down_arrow}), this barrier is shown to be magnetized in the sense that excess {up_arrow}-spin atoms are localized around it. The resulting superfluid Fermi gas is spatially divided into two by this ferromagnet, so that one obtains amore » junction similar to the superconductor-ferromagnet-superconductor junction discussed in superconductivity. Indeed, we show that the so-called {pi} phase, which is a typical phenomenon in the SFS junction, is realized, where the superfluid order parameter changes its sign across the junction. Our results would be useful for the study of magnetic effects on fermion superfluidity using an ultracold Fermi gas.« less

  13. Direct evidence that ganglioside is an integral component of the thyrotropin receptor

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

    Kielczynski, W.; Harrison, L.C.; Leedman, P.J.

    1991-03-01

    Gangliosides were extracted from purified human and porcine thyrotropin (TSH) receptors (TSH-R) and were detected by probing with an {sup 125}I-labeled sialic acid-specific lectin, Limax flavus agglutinin. Gangliosides copurified with human and porcine TSH-R migrated between monosialoganglioside GM1 and disialoganglioside GD1a. Ceramide glycanase digestion of the purified human TSH-R-associated glycolipid confirmed its ganglioside nature. It was resistant to Vibrio cholerae sialidase, which digest all gangliosides except GM1, but was sensitive to Arthrobacter ureafaciens sialidase, which digests all gangliosides including GM1. These findings indicate that the human TSH-R contains ganglioside that belongs to the galactosyl({beta}1{r arrow} 3)-N-acetylgalactosaminyl({beta}1{r arrow} 4)-(N-acetylneuraminyl({alpha}2{r arrow} 3))galactosyl({beta}1more » {r arrow} 4)glucosyl({beta}1 {r arrow} 1)ceramide (GM1) family. Its intimate association with receptor protein implies a key role for ganglioside in the structure and function of the TSH-R.« less

  14. Dynamic flashing yellow arrow (FYA) : a study on variable left turn mode operational and safety impacts.

    DOT National Transportation Integrated Search

    2013-12-01

    Accommodating left turns at signalized intersections has been a challenge for traffic engineers as they : seek balance between two conflicting goals; capacity and safety. The use of a four-section head for the left-turn : lane only with a flashing ye...

  15. ACHP | News | ACHP Spring Business Meeting May 5

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Chairman Wayne Donaldson Celebrates with LA Preserve America Neighborhoods ACHP Chairman Wayne Donaldson Celebrates with LA Preserve America

  16. Postural stability, clicker reaction time and bow draw force predict performance in elite recurve archery.

    PubMed

    Spratford, Wayne; Campbell, Rhiannon

    2017-06-01

    Recurve archery is an Olympic sport that requires extreme precision, upper body strength and endurance. The purpose of this research was to quantify how postural stability variables both pre- and post-arrow release, draw force, flight time, arrow length and clicker reaction time, collectively, impacted on the performance or scoring outcomes in elite recurve archery athletes. Thirty-nine elite-level recurve archers (23 male and 16 female; mean age = 24.7 ± 7.3 years) from four different countries volunteered to participate in this study prior to competing at a World Cup event. An AMTI force platform (1000Hz) was used to obtain centre of pressure (COP) measurements 1s prior to arrow release and 0.5s post-arrow release. High-speed footage (200Hz) allowed for calculation of arrow flight time and score. Results identified clicker reaction time, draw force and maximum sway speed as the variables that best predicted shot performance. Specifically, reduced clicker reaction time, greater bow draw force and reduced postural sway speed post-arrow release were predictors of higher scoring shots. It is suggested that future research should focus on investigating shoulder muscle tremors at full draw in relation to clicker reaction time, and the effect of upper body strength interventions (specifically targeting the musculature around the shoulder girdle) on performance in recurve archers.

  17. Achilles' death: anatomical considerations regarding the most famous trauma of the Trojan War.

    PubMed

    Anagnostopoulou, Sophia; Mavridis, Ioannis

    2013-03-01

    In Greek mythology, Achilles was a hero of the Trojan War, the central character and greatest warrior of Homer's Iliad. As Achilles died because of a small wound on his heel, the term "Achilles' heel" has come to mean a person's principal weakness. But is the human heel a really vulnerable part of our body? Could a non-poisonous arrow have caused Achilles' death? Should an arrow be necessarily poisonous in order to cause a lethal heel would? The purpose of this effort is to explain, from an anatomic point of view, how Achilles heel wounding could have led to his death. The Achilles tendon is the strongest, largest and thickest tendon in the human body and plays an important role in the biomechanics of the lower extremity. The blood supply of the tendon is from the peroneal and posterior tibial arteries. It is quite likely that the arrow which killed Achilles was poisoned. This supposition could be of course enough to cause his death. In case the arrow was not poisoned a rupture of the posterior tibial artery by the arrow could have caused a bleeding, but it seems unlikely for such a bleeding to be lethal. Moreover, a combination of these two theories could have also taken place, i.e. a poisoned arrow traumatizing the posterior tibial artery and hence causing rapid diffusion of the poison as well as bleeding. Furthermore, infectious and/or immunologic bases regarding Achilles' death could be considered. In our opinion, a poisoned arrow was probably the crucial factor leading to the famous inglorious death of this famous glorious Homeric hero.

  18. Platforms for Persistent communications Surveillance and Reconnaissance - II

    DTIC Science & Technology

    2009-11-01

    Lifter Airship with a comprehensive suite of sensors as indicated by the green line at the top of the chart with the red arrow. It had a value more than...package, but it was not as capable as the robust sensor suite on the red arrow option. Platforms for Persistent CSR II - 30...sensors remained the top-ranked option as indicated by the green line at the top of the chart with the red arrow. However, its value dropped from 0.253 on

  19. Toddler signaling regulates mesodermal cell migration downstream of Nodal signaling

    PubMed Central

    Norris, Megan L; Pauli, Andrea; Gagnon, James A; Lord, Nathan D; Rogers, Katherine W; Mosimann, Christian; Zon, Leonard I

    2017-01-01

    Toddler/Apela/Elabela is a conserved secreted peptide that regulates mesendoderm development during zebrafish gastrulation. Two non-exclusive models have been proposed to explain Toddler function. The ‘specification model’ postulates that Toddler signaling enhances Nodal signaling to properly specify endoderm, whereas the ‘migration model’ posits that Toddler signaling regulates mesendodermal cell migration downstream of Nodal signaling. Here, we test key predictions of both models. We find that in toddler mutants Nodal signaling is initially normal and increasing endoderm specification does not rescue mesendodermal cell migration. Mesodermal cell migration defects in toddler mutants result from a decrease in animal pole-directed migration and are independent of endoderm. Conversely, endodermal cell migration defects are dependent on a Cxcr4a-regulated tether of the endoderm to mesoderm. These results suggest that Toddler signaling regulates mesodermal cell migration downstream of Nodal signaling and indirectly affects endodermal cell migration via Cxcr4a-signaling. PMID:29117894

  20. Frequency domain laser velocimeter signal processor: A new signal processing scheme

    NASA Technical Reports Server (NTRS)

    Meyers, James F.; Clemmons, James I., Jr.

    1987-01-01

    A new scheme for processing signals from laser velocimeter systems is described. The technique utilizes the capabilities of advanced digital electronics to yield a smart instrument that is able to configure itself, based on the characteristics of the input signals, for optimum measurement accuracy. The signal processor is composed of a high-speed 2-bit transient recorder for signal capture and a combination of adaptive digital filters with energy and/or zero crossing detection signal processing. The system is designed to accept signals with frequencies up to 100 MHz with standard deviations up to 20 percent of the average signal frequency. Results from comparative simulation studies indicate measurement accuracies 2.5 times better than with a high-speed burst counter, from signals with as few as 150 photons per burst.

  1. 29 CFR 1926.1421 - Signals-voice signals-additional requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Signals-voice signals-additional requirements. 1926.1421... Derricks in Construction § 1926.1421 Signals—voice signals—additional requirements. (a) Prior to beginning operations, the operator, signal person and lift director (if there is one), must contact each other and...

  2. 29 CFR 1926.1421 - Signals-voice signals-additional requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Signals-voice signals-additional requirements. 1926.1421... Derricks in Construction § 1926.1421 Signals—voice signals—additional requirements. (a) Prior to beginning operations, the operator, signal person and lift director (if there is one), must contact each other and...

  3. 29 CFR 1926.1421 - Signals-voice signals-additional requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Signals-voice signals-additional requirements. 1926.1421... Derricks in Construction § 1926.1421 Signals—voice signals—additional requirements. (a) Prior to beginning operations, the operator, signal person and lift director (if there is one), must contact each other and...

  4. Elementary signaling modes predict the essentiality of signal transduction network components

    PubMed Central

    2011-01-01

    Background Understanding how signals propagate through signaling pathways and networks is a central goal in systems biology. Quantitative dynamic models help to achieve this understanding, but are difficult to construct and validate because of the scarcity of known mechanistic details and kinetic parameters. Structural and qualitative analysis is emerging as a feasible and useful alternative for interpreting signal transduction. Results In this work, we present an integrative computational method for evaluating the essentiality of components in signaling networks. This approach expands an existing signaling network to a richer representation that incorporates the positive or negative nature of interactions and the synergistic behaviors among multiple components. Our method simulates both knockout and constitutive activation of components as node disruptions, and takes into account the possible cascading effects of a node's disruption. We introduce the concept of elementary signaling mode (ESM), as the minimal set of nodes that can perform signal transduction independently. Our method ranks the importance of signaling components by the effects of their perturbation on the ESMs of the network. Validation on several signaling networks describing the immune response of mammals to bacteria, guard cell abscisic acid signaling in plants, and T cell receptor signaling shows that this method can effectively uncover the essentiality of components mediating a signal transduction process and results in strong agreement with the results of Boolean (logical) dynamic models and experimental observations. Conclusions This integrative method is an efficient procedure for exploratory analysis of large signaling and regulatory networks where dynamic modeling or experimental tests are impractical. Its results serve as testable predictions, provide insights into signal transduction and regulatory mechanisms and can guide targeted computational or experimental follow-up studies. The

  5. ACHP | ACHP Receives Section 213 Report on Presidio of San Francisco

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Receives Section 213 Report on Presidio of San Francisco ACHP Receives Section 213 Report on Presidio of San Francisco The ACHP received its requested

  6. Human cortical activity evoked by contextual processing in attentional orienting.

    PubMed

    Zhao, Shuo; Li, Chunlin; Uono, Shota; Yoshimura, Sayaka; Toichi, Motomi

    2017-06-07

    The ability to assess another person's direction of attention is paramount in social communication, many studies have reported a similar pattern between gaze and arrow cues in attention orienting. Neuroimaging research has also demonstrated no qualitative differences in attention to gaze and arrow cues. However, these studies were implemented under simple experiment conditions. Researchers have highlighted the importance of contextual processing (i.e., the semantic congruence between cue and target) in attentional orienting, showing that attentional orienting by social gaze or arrow cues could be modulated through contextual processing. Here, we examine the neural activity of attentional orienting by gaze and arrow cues in response to contextual processing using functional magnetic resonance imaging. The results demonstrated that the influence of neural activity through contextual processing to attentional orienting occurred under invalid conditions (when the cue and target were incongruent versus congruent) in the ventral frontoparietal network, although we did not identify any differences in the neural substrates of attentional orienting in contextual processing between gaze and arrow cues. These results support behavioural data of attentional orienting modulated by contextual processing based on the neurocognitive architecture.

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

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

    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 maymore » constitute a clinically recognizable syndrome. 13 refs., 2 figs., 2 tabs.« less

  8. {sup 17}O Knight shift study of the superconducting state of Sr{sub 2}RuO{sub 4}

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

    Mukuda, H.; Ishida, K.; Kitaoka, Y.

    1999-12-01

    {sup 17}O Knight shift measurements in Sr{sub 2}RuO{sub 4} were performed over the wide range of magnetic field 3.2--11.4kOe parallel to the basal RuO{sub 2} planes. The spin susceptibility is totally unchanged through its T{prime}{sub c}, evidencing that the spin-triplet superconducting state is realized in Sr{sub 2}RuO{sub 4}. The results indicates that the Cooper pairs consist of the parallel spin pairs {vert{underscore}bar}{up{underscore}arrow}{up{underscore}arrow}> and {vert{underscore}bar}{down{underscore}arrow}{down{underscore}arrow}> with their quantization axis perpendicular to the c-axis direction. The in-plane 2D nearly ferromagnetic spin fluctuations may play a role for the stabilization of this state among various representations of spin-triplet order parameter.

  9. [Analysis and research of brain-computer interface experiments for imaging left-right hands movement].

    PubMed

    Wu, Yazhou; He, Qinghua; Huang, Hua; Zhang, Ling; Zhuo, Yu; Xie, Qi; Wu, Baoming

    2008-10-01

    This is a research carried out to explore a pragmatic way of BCI based imaging movement, i. e. to extract the feature of EEG for reflecting different thinking by searching suitable methods of signal extraction and recognition algorithm processing, to boost the recognition rate of communication for BCI system, and finally to establish a substantial theory and experimental support for BCI application. In this paper, different mental tasks for imaging left-right hands movement from 6 subjects were studied in three different time sections (hint keying at 2s, 1s and 0s after appearance of arrow). Then we used wavelet analysis and Feed-forward Back-propagation Neural Network (BP-NN) method for processing and analyzing the experimental data of off-line. Delay time delta t2, delta t1 and delta t0 for all subjects in the three different time sections were analyzed. There was significant difference between delta to and delta t2 or delta t1 (P<0.05), but no significant difference was noted between delta t2 and delta t1 (P>0.05). The average results of recognition rate were 65%, 86.67% and 72%, respectively. There were obviously different features for imaging left-right hands movement about 0.5-1s before actual movement; these features displayed significant difference. We got higher recognition rate of communication under the hint keying at about 1s after the appearance of arrow. These showed the feasibility of using the feature signals extracted from the project as the external control signals for BCI system, and demon strated that the project provided new ideas and methods for feature extraction and classification of mental tasks for BCI.

  10. Transient-Switch-Signal Suppressor

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr.

    1995-01-01

    Circuit delays transmission of switch-opening or switch-closing signal until after preset suppression time. Used to prevent transmission of undesired momentary switch signal. Basic mode of operation simple. Beginning of switch signal initiates timing sequence. If switch signal persists after preset suppression time, circuit transmits switch signal to external circuitry. If switch signal no longer present after suppression time, switch signal deemed transient, and circuit does not pass signal on to external circuitry, as though no transient switch signal. Suppression time preset at value large enough to allow for damping of underlying pressure wave or other mechanical transient.

  11. 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.

  12. Regulation of Phagocyte Migration by Signal Regulatory Protein-Alpha Signaling

    PubMed Central

    Alvarez-Zarate, Julian; Matlung, Hanke L.; Matozaki, Takashi; Kuijpers, Taco W.; Maridonneau-Parini, Isabelle; van den Berg, Timo K.

    2015-01-01

    Signaling through the inhibitory receptor signal regulatory protein-alpha (SIRPα) controls effector functions in phagocytes. However, there are also indications that interactions between SIRPα and its ligand CD47 are involved in phagocyte transendothelial migration. We have investigated the involvement of SIRPα signaling in phagocyte migration in vitro and in vivo using mice that lack the SIRPα cytoplasmic tail. During thioglycolate-induced peritonitis in SIRPα mutant mice, both neutrophil and macrophage influx were found to occur, but to be significantly delayed. SIRPα signaling appeared to be essential for an optimal transendothelial migration and chemotaxis, and for the amoeboid type of phagocyte migration in 3-dimensional environments. These findings demonstrate, for the first time, that SIRPα signaling can directly control phagocyte migration, and this may contribute to the impaired inflammatory phenotype that has been observed in the absence of SIRPα signaling. PMID:26057870

  13. Regulation of Phagocyte Migration by Signal Regulatory Protein-Alpha Signaling.

    PubMed

    Alvarez-Zarate, Julian; Matlung, Hanke L; Matozaki, Takashi; Kuijpers, Taco W; Maridonneau-Parini, Isabelle; van den Berg, Timo K

    2015-01-01

    Signaling through the inhibitory receptor signal regulatory protein-alpha (SIRPα) controls effector functions in phagocytes. However, there are also indications that interactions between SIRPα and its ligand CD47 are involved in phagocyte transendothelial migration. We have investigated the involvement of SIRPα signaling in phagocyte migration in vitro and in vivo using mice that lack the SIRPα cytoplasmic tail. During thioglycolate-induced peritonitis in SIRPα mutant mice, both neutrophil and macrophage influx were found to occur, but to be significantly delayed. SIRPα signaling appeared to be essential for an optimal transendothelial migration and chemotaxis, and for the amoeboid type of phagocyte migration in 3-dimensional environments. These findings demonstrate, for the first time, that SIRPα signaling can directly control phagocyte migration, and this may contribute to the impaired inflammatory phenotype that has been observed in the absence of SIRPα signaling.

  14. Optical signal processing

    NASA Technical Reports Server (NTRS)

    Casasent, D.

    1978-01-01

    The article discusses several optical configurations used for signal processing. Electronic-to-optical transducers are outlined, noting fixed window transducers and moving window acousto-optic transducers. Folded spectrum techniques are considered, with reference to wideband RF signal analysis, fetal electroencephalogram analysis, engine vibration analysis, signal buried in noise, and spatial filtering. Various methods for radar signal processing are described, such as phased-array antennas, the optical processing of phased-array data, pulsed Doppler and FM radar systems, a multichannel one-dimensional optical correlator, correlations with long coded waveforms, and Doppler signal processing. Means for noncoherent optical signal processing are noted, including an optical correlator for speech recognition and a noncoherent optical correlator.

  15. Digital signal processing the Tevatron BPM signals

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

    Cancelo, G.; James, E.; Wolbers, S.

    2005-05-01

    The Beam Position Monitor (TeV BPM) readout system at Fermilab's Tevatron has been updated and is currently being commissioned. The new BPMs use new analog and digital hardware to achieve better beam position measurement resolution. The new system reads signals from both ends of the existing directional stripline pickups to provide simultaneous proton and antiproton measurements. The signals provided by the two ends of the BPM pickups are processed by analog band-pass filters and sampled by 14-bit ADCs at 74.3MHz. A crucial part of this work has been the design of digital filters that process the signal. This paper describesmore » the digital processing and estimation techniques used to optimize the beam position measurement. The BPM electronics must operate in narrow-band and wide-band modes to enable measurements of closed-orbit and turn-by-turn positions. The filtering and timing conditions of the signals are tuned accordingly for the operational modes. The analysis and the optimized result for each mode are presented.« less

  16. SignalPlant: an open signal processing software platform.

    PubMed

    Plesinger, F; Jurco, J; Halamek, J; Jurak, P

    2016-07-01

    The growing technical standard of acquisition systems allows the acquisition of large records, often reaching gigabytes or more in size as is the case with whole-day electroencephalograph (EEG) recordings, for example. Although current 64-bit software for signal processing is able to process (e.g. filter, analyze, etc) such data, visual inspection and labeling will probably suffer from rather long latency during the rendering of large portions of recorded signals. For this reason, we have developed SignalPlant-a stand-alone application for signal inspection, labeling and processing. The main motivation was to supply investigators with a tool allowing fast and interactive work with large multichannel records produced by EEG, electrocardiograph and similar devices. The rendering latency was compared with EEGLAB and proves significantly faster when displaying an image from a large number of samples (e.g. 163-times faster for 75  ×  10(6) samples). The presented SignalPlant software is available free and does not depend on any other computation software. Furthermore, it can be extended with plugins by third parties ensuring its adaptability to future research tasks and new data formats.

  17. Signal-3L: A 3-layer approach for predicting signal peptides.

    PubMed

    Shen, Hong-Bin; Chou, Kuo-Chen

    2007-11-16

    Functioning as an "address tag" that directs nascent proteins to their proper cellular and extracellular locations, signal peptides have become a crucial tool in finding new drugs or reprogramming cells for gene therapy. To effectively and timely use such a tool, however, the first important thing is to develop an automated method for rapidly and accurately identifying the signal peptide for a given nascent protein. With the avalanche of new protein sequences generated in the post-genomic era, the challenge has become even more urgent and critical. In this paper, we have developed a novel method for predicting signal peptide sequences and their cleavage sites in human, plant, animal, eukaryotic, Gram-positive, and Gram-negative protein sequences, respectively. The new predictor is called Signal-3L that consists of three prediction engines working, respectively, for the following three progressively deepening layers: (1) identifying a query protein as secretory or non-secretory by an ensemble classifier formed by fusing many individual OET-KNN (optimized evidence-theoretic K nearest neighbor) classifiers operated in various dimensions of PseAA (pseudo amino acid) composition spaces; (2) selecting a set of candidates for the possible signal peptide cleavage sites of a query secretory protein by a subsite-coupled discrimination algorithm; (3) determining the final cleavage site by fusing the global sequence alignment outcome for each of the aforementioned candidates through a voting system. Signal-3L is featured by high success prediction rates with short computational time, and hence is particularly useful for the analysis of large-scale datasets. Signal-3L is freely available as a web-server at http://chou.med.harvard.edu/bioinf/Signal-3L/ or http://202.120.37.186/bioinf/Signal-3L, where, to further support the demand of the related areas, the signal peptides identified by Signal-3L for all the protein entries in Swiss-Prot databank that do not have signal peptide

  18. Quaternion-Based Signal Analysis for Motor Imagery Classification from Electroencephalographic Signals.

    PubMed

    Batres-Mendoza, Patricia; Montoro-Sanjose, Carlos R; Guerra-Hernandez, Erick I; Almanza-Ojeda, Dora L; Rostro-Gonzalez, Horacio; Romero-Troncoso, Rene J; Ibarra-Manzano, Mario A

    2016-03-05

    Quaternions can be used as an alternative to model the fundamental patterns of electroencephalographic (EEG) signals in the time domain. Thus, this article presents a new quaternion-based technique known as quaternion-based signal analysis (QSA) to represent EEG signals obtained using a brain-computer interface (BCI) device to detect and interpret cognitive activity. This quaternion-based signal analysis technique can extract features to represent brain activity related to motor imagery accurately in various mental states. Experimental tests in which users where shown visual graphical cues related to left and right movements were used to collect BCI-recorded signals. These signals were then classified using decision trees (DT), support vector machine (SVM) and k-nearest neighbor (KNN) techniques. The quantitative analysis of the classifiers demonstrates that this technique can be used as an alternative in the EEG-signal modeling phase to identify mental states.

  19. Quaternion-Based Signal Analysis for Motor Imagery Classification from Electroencephalographic Signals

    PubMed Central

    Batres-Mendoza, Patricia; Montoro-Sanjose, Carlos R.; Guerra-Hernandez, Erick I.; Almanza-Ojeda, Dora L.; Rostro-Gonzalez, Horacio; Romero-Troncoso, Rene J.; Ibarra-Manzano, Mario A.

    2016-01-01

    Quaternions can be used as an alternative to model the fundamental patterns of electroencephalographic (EEG) signals in the time domain. Thus, this article presents a new quaternion-based technique known as quaternion-based signal analysis (QSA) to represent EEG signals obtained using a brain-computer interface (BCI) device to detect and interpret cognitive activity. This quaternion-based signal analysis technique can extract features to represent brain activity related to motor imagery accurately in various mental states. Experimental tests in which users where shown visual graphical cues related to left and right movements were used to collect BCI-recorded signals. These signals were then classified using decision trees (DT), support vector machine (SVM) and k-nearest neighbor (KNN) techniques. The quantitative analysis of the classifiers demonstrates that this technique can be used as an alternative in the EEG-signal modeling phase to identify mental states. PMID:26959029

  20. Tunable Signal-Off and Signal-On Electrochemical Cisplatin Sensor.

    PubMed

    Wu, Yao; Lai, Rebecca Y

    2017-09-19

    We report the first electrochemical cisplatin sensor fabricated with a thiolated and methylene blue (MB)-modified oligo-adenine (A)-guanine (G) DNA probe. Depending on the probe coverage, the sensor can behave as a signal-off or signal-on sensor. For the high-coverage sensor, formation of intrastrand Pt(II)-AG adducts rigidifies the oligo-AG probe, resulting in a concentration-dependent decrease in the MB signal. For the low-coverage sensor, the increase in probe-to-probe spacing enables binding of cisplatin via the intrastrand GNG motif (N = A), generating a bend in the probe which results in an increase in the MB current. Although both high-coverage signal-off and low-coverage signal-on sensors are capable of detecting cisplatin, the signal-on sensing mechanism is better suited for real time analysis of cisplatin. The low-coverage sensor has a lower limit of detection, wider optimal AC frequency range, and faster response time. It has high specificity for cisplatin and potentially other Pt(II) drugs and does not cross-react with satraplatin, a Pt(IV) prodrug. It is also selective enough to be employed directly in 50% saliva and 50% urine. This detection strategy may offer a new approach for sensitive and real time analysis of cisplatin in clinical samples.

  1. Signal Restoration of Non-stationary Acoustic Signals in the Time Domain

    NASA Technical Reports Server (NTRS)

    Babkin, Alexander S.

    1988-01-01

    Signal restoration is a method of transforming a nonstationary signal acquired by a ground based microphone to an equivalent stationary signal. The benefit of the signal restoration is a simplification of the flight test requirements because it could dispense with the need to acquire acoustic data with another aircraft flying in concert with the rotorcraft. The data quality is also generally improved because the contamination of the signal by the propeller and wind noise is not present. The restoration methodology can also be combined with other data acquisition methods, such as a multiple linear microphone array for further improvement of the test results. The methodology and software are presented for performing the signal restoration in the time domain. The method has no restrictions on flight path geometry or flight regimes. Only requirement is that the aircraft spatial position be known relative to the microphone location and synchronized with the acoustic data. The restoration process assumes that the moving source radiates a stationary signal, which is then transformed into a nonstationary signal by various modulation processes. The restoration contains only the modulation due to the source motion.

  2. The spatiotemporal order of signaling events unveils the logic of development signaling.

    PubMed

    Zhu, Hao; Owen, Markus R; Mao, Yanlan

    2016-08-01

    Animals from worms and insects to birds and mammals show distinct body plans; however, the embryonic development of diverse body plans with tissues and organs within is controlled by a surprisingly few signaling pathways. It is well recognized that combinatorial use of and dynamic interactions among signaling pathways follow specific logic to control complex and accurate developmental signaling and patterning, but it remains elusive what such logic is, or even, what it looks like. We have developed a computational model for Drosophila eye development with innovated methods to reveal how interactions among multiple pathways control the dynamically generated hexagonal array of R8 cells. We obtained two novel findings. First, the coupling between the long-range inductive signals produced by the proneural Hh signaling and the short-range restrictive signals produced by the antineural Notch and EGFR signaling is essential for generating accurately spaced R8s. Second, the spatiotemporal orders of key signaling events reveal a robust pattern of lateral inhibition conducted by Ato-coordinated Notch and EGFR signaling to collectively determine R8 patterning. This pattern, stipulating the orders of signaling and comparable to the protocols of communication, may help decipher the well-appreciated but poorly defined logic of developmental signaling. The model is available upon request. hao.zhu@ymail.com Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  3. The spatiotemporal order of signaling events unveils the logic of development signaling

    PubMed Central

    Zhu, Hao; Owen, Markus R.; Mao, Yanlan

    2016-01-01

    Motivation: Animals from worms and insects to birds and mammals show distinct body plans; however, the embryonic development of diverse body plans with tissues and organs within is controlled by a surprisingly few signaling pathways. It is well recognized that combinatorial use of and dynamic interactions among signaling pathways follow specific logic to control complex and accurate developmental signaling and patterning, but it remains elusive what such logic is, or even, what it looks like. Results: We have developed a computational model for Drosophila eye development with innovated methods to reveal how interactions among multiple pathways control the dynamically generated hexagonal array of R8 cells. We obtained two novel findings. First, the coupling between the long-range inductive signals produced by the proneural Hh signaling and the short-range restrictive signals produced by the antineural Notch and EGFR signaling is essential for generating accurately spaced R8s. Second, the spatiotemporal orders of key signaling events reveal a robust pattern of lateral inhibition conducted by Ato-coordinated Notch and EGFR signaling to collectively determine R8 patterning. This pattern, stipulating the orders of signaling and comparable to the protocols of communication, may help decipher the well-appreciated but poorly defined logic of developmental signaling. Availability and implementation: The model is available upon request. Contact: hao.zhu@ymail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153573

  4. ACHP | News | ACHP Issue Spotlight: Transmission Lines in the West

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Approves Policy Statement Regarding Federal Relationships with Tribal Historic Preservation Officers ACHP Approves Policy Statement Regarding Federal approved the ACHP Policy Statement Regarding Federal Relationships with Tribal Historic Preservation

  5. Promoting Positive Youth Development in the Face of Contextual Changes and Challenges: The Roles of Individual Strengths and Ecological Assets

    ERIC Educational Resources Information Center

    Lerner, Richard M.; Bowers, Edmond P.; Geldhof, G. John; Gestsdottir, Steinunn; DeSouza, Lisette

    2012-01-01

    Contemporary developmental theory is framed by relational developmental systems models that emphasize that change across life occurs through mutually regulative relations between individuals and their contexts (represented as individual [left arrow][right arrow] context relations). Within these models, all contextual levels are involved in these…

  6. Production of a pseudoscalar Higgs boson with a Z boson from gluon fusion

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

    Kao, C.

    1992-12-01

    The minimal supersymmetric model is adopted to study the production of a pseudoscalar Higgs boson ({ital A}) in association with a {ital Z} gauge boson from gluon fusion ({ital gg}{r arrow}{ital ZA}) at future hadron supercolliders. Its production rate is determined and compared to that of the associated production of the standard model Higgs boson ({ital H}{sub SM}) with a {ital Z} boson from quark-antiquark annihilation ({ital q{bar q}}{r arrow}{ital ZH}{sub SM}) and gluon fusion ({ital gg}{r arrow}{ital ZH}{sub SM}). Some promising decay modes are suggested for detection.

  7. 29 CFR 1926.1422 - Signals-hand signal chart.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Signals-hand signal chart. 1926.1422 Section 1926.1422 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in...

  8. 49 CFR 236.514 - Interconnection of cab signal system with roadway signal system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Standards § 236.514 Interconnection of cab signal system with roadway signal system. The automatic cab signal system shall be...

  9. Analysis of Adhesively Bonded Ceramics Using an Asymmetric Wedge Test

    DTIC Science & Technology

    2008-12-01

    4 Figure 2. Average crack ...flexure specimen. The flaw, indicated by the white arrow, is a subsurface semi-elliptical crack induced by surface machining damage...strength-limiting orthogonal surface machining crack in an alumina flexure specimen coated with a single layer of film adhesive. The white arrow

  10. 29 CFR 1926.1421 - Signals-voice signals-additional requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... operations, the operator, signal person and lift director (if there is one), must contact each other and....), direction; distance and/or speed; function, stop command. (c) The operator, signal person and lift director...

  11. Duplication of 7p: Further delineation of the phenotype and restriction of the critical region to the distal part of the short arm

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

    Reish, O.; Berry, S.A.; King, R.A.

    We report on a patient with duplication of 7p15{r_arrow}pter and review of the literature. Patients with partial duplication of the distal 7p, including only the distal segment 7p15{r_arrow}pter, have a syndrome comparable to that of patients with a larger or complete duplication of 7p. This suggests that the critical region for the dup(7p) phenotype is restricted to 7p15{r_arrow}pter. The complete clinical phenotype of dup (7)(p15{r_arrow}pter) includes mental retardation, skull anomalies, large anterior fontanel, cardiovascular defects, joint dislocation and contraction, and gastrointestinal and genital defects. Recognition of the clinical spectrum in patients with a smaller duplication 7p, and the assignment ofmore » this critical region, should prove valuable for accurate counseling, prediction of outcome, and further gene mapping. 33 refs., 3 figs., 2 tabs.« less

  12. Four novel cystic fibrosis mutations in splice junction sequences affecting the CFTR nucleotide binding folds

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

    Doerk, T.; Wulbrand, U.; Tuemmler, B.

    1993-03-01

    Single cases of the four novel splice site mutations 1525[minus]1 G [r arrow] A (intron 9), 3601[minus]2 A [r arrow] G (intron 18), 3850[minus]3 T [r arrow] G (intron 19), and 4374+1 G [r arrow] T (intron 23) were detected in the CFTR gene of cystic fibrosis patients of Indo-Iranian, Turkish, Polish, and Germany descent. The nucleotide substitutions at the +1, [minus]1, and [minus]2 positions all destroy splice sites and lead to severe disease alleles associated with features typical of gastrointestinal and pulmonary cystic fibrosis disease. The 3850[minus]3 T-to-G change was discovered in a very mildly affected 33-year-old [Delta]F508 compoundmore » heterozygote, suggesting that the T-to-G transversion at the less conserved [minus]3 position of the acceptor splice site may retain some wildtype function. 13 refs., 1 fig., 2 tabs.« less

  13. The Nature and Origin of Time-Asymmetric Spacetime Structures

    NASA Astrophysics Data System (ADS)

    Zeh, H. Dieter

    Time-asymmetric spacetime structures, in particular those representing black holes and the expansion of the universe, are intimately related to other arrows of time, such as the second law and the retardation of radiation. The nature of the quantum arrow, often attributed to a collapse of the wave function, is essential, in particular, for understanding the much discussed black hole information loss paradox. This paradox assumes a new form and can possibly be avoided in a consistent causal treatment that may be able to avoid horizons and singularities. The master arrow that would combine all arrows of time does not have to be identified with a direction of the formal time parameter that serves to formulate the dynamics as a succession of global states (a trajectory in configuration or Hilbert space). It may even change direction with respect to a fundamental physical clock such as the cosmic expansion parameter if this was formally extended either into a future contraction era or to negative pre-big-bang values.

  14. Dynamic flashing yellow arrow (FYA) : a study on variable left turn model operational and safety impacts, [technical summary].

    DOT National Transportation Integrated Search

    2013-12-01

    Traffic engineers use various left-turn signalization : methods to find an optimal balance of safety and : efficiency. While protected/permitted left-turn : configurations allow most left-turning traffic to : turn during the protected phase, the perm...

  15. Principles of signal conditioning.

    PubMed

    Finkel, A; Bookman, R

    2001-05-01

    It is rare for biological, physiological, chemical, electrical, or physical signals to be measured in the appropriate format for recording and interpretation. Usually, a signal must be conditioned to optimize it for both of these functions. This overview describes the fundamentals of signal filtering, how to prepare signals for A/D conversion, signal averaging to increase the signal-to-noise ratio, line frequency pickup (hum), peak-to-peak and rms noise measurements, blanking, audio monitoring, testing of electrodes and the common-mode rejection ratio.

  16. Hybrid optofluidic biosensors

    NASA Astrophysics Data System (ADS)

    Parks, Joshua W.

    Optofluidics, born of the desire to create a system containing microfluidic environments with integrated optical elements, has seen dramatic increases in popularity over the last 10 years. In particular, the application of this technology towards chip based molecular sensors has undergone significant development. The most sensitive of these biosensors interface liquid- and solid-core antiresonant reflecting optical waveguides (ARROWs). These sensor chips are created using conventional silicon microfabrication. As such, ARROW technology has previously been unable to utilize state-of-the-art microfluidic developments because the technology used--soft polydimethyl siloxane (PDMS) micromolded chips--is unamenable to the silicon microfabrication workflows implemented in the creation of ARROW detection chips. The original goal of this thesis was to employ hybrid integration, or the connection of independently designed and fabricated optofluidic and microfluidic chips, to create enhanced biosensors with the capability of processing and detecting biological samples on a single hybrid system. After successful demonstration of this paradigm, this work expanded into a new direction--direct integration of sensing and detection technologies on a new platform with dynamic, multi-dimensional photonic re-configurability. This thesis reports a number of firsts, including: • 1,000 fold optical transmission enhancement of ARROW optofluidic detection chips through thermal annealing, • Detection of single nucleic acids on a silicon-based ARROW chip, • Hybrid optofluidic integration of ARROW detection chips and passive PDMS microfluidic chips, • Hybrid optofluidic integration of ARROW detection chips and actively controllable PDMS microfluidic chips with integrated microvalves, • On-chip concentration and detection of clinical Ebola nucleic acids, • Multimode interference (MMI) waveguide based wavelength division multiplexing for detection of single influenza virions,

  17. Nichtkontinuierliche (zeitdiskrete) Signale

    NASA Astrophysics Data System (ADS)

    Plaßmann, Wilfried

    Zeitdiskrete Signale werden häufig aus zeitkontinuierlichen Signalen durch Abtastung erzeugt. Dass beide Signale gleichwertig sind, zeigt das Abtasttheorem (Kap. 116) von Shannon, sofern die Bedingung nach (116.2), f_{ab}≈(2{,}2 {\\ldots} 4)\\cdot fg) eingehalten wird. Digitale Signale haben Vorteile: Einfache Speicherung, Weiterverarbeitung in Rechnern, wenig störanfällige Übertragung. Für die Bearbeitung dieser Signale dienen die im Kapitel dargestellten Hilfsmittel: Diskrete Fouriertransformation; Schnelle Fouriertransformation; z-Transformation: Darstellung, Sätze zur z-Transformation, Korrespondenzen zu Zeitfunktionen, Beispiele.

  18. ACHP | News | Legislation Passes Senate

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Legislation Passes Senate Secretary Kempthorne continue historic preservation programs founded by each of the past two First Ladies in legislation passed Hillary Clinton. "Bipartisan approval of this legislation by an overwhelming margin reflects the

  19. ACHP | Using Section 106 to Protect Historic Properties brochure

    Science.gov Websites

    Search skip specific nav links Home arrow Publications arrow Intro: "Using Section 106 to Protect Historic Properties" brochure Using Section 106 to Protect Historic Properties 2002; 6-panel brochure Federal decisions that impact historic properties. The brochure, "Using Section 106 to Protect

  20. ACHP | "The Section 106 Advanced" Course

    Science.gov Websites

    Working with Section 106 Federal, State, & Tribal Programs Training & Education Publications Search skip specific nav links Home arrow Training and Education arrow Advanced Section 106 Seminar Essentials Training Course? Looking for the Section 106 Basics Course? Course Description An in-depth look at

  1. ACHP | News | Nationwide Programmatic Agreement Streamlines 106 Process for

    Science.gov Websites

    Publications Search skip specific nav links Home arrow News arrow Nationwide Programmatic Agreement Streamlines 106 Process for NPS Nationwide Programmatic Agreement Streamlines 106 Process for NPS Pursuant to Service (NPS) on November 14, 2008, executed a nationwide Programmatic Agreement (PA) with the Advisory

  2. ACHP | News | St. Elizabeths Programmatic Agreement Signed

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow St. Elizabeths Programmatic Agreement Signed St . Elizabeths Programmatic Agreement Signed December 9, 2008-- The General Services Administration (GSA), the ), and the Department of Homeland Security (DHS) executed a Programmatic Agreement (PA) for the

  3. Dampened Hedgehog signaling but normal Wnt signaling in zebrafish without cilia

    PubMed Central

    Huang, Peng; Schier, Alexander F.

    2009-01-01

    Summary Cilia have been implicated in Hedgehog (Hh) and Wnt signaling in mouse but not in Drosophila. To determine whether the role of cilia is conserved in zebrafish, we generated maternal-zygotic (MZ) oval (ovl; ift88) mutants that lack all cilia. MZovl mutants display normal canonical and non-canonical Wnt signaling but show defects in Hh signaling. As in mouse, zebrafish cilia are required to mediate the activities of Hh, Ptc, Smo and PKA. However, in contrast to mouse Ift88 mutants, which show a dramatic reduction in Hh signaling, zebrafish MZovl mutants display dampened, but expanded, Hh pathway activity. This activity is largely due to gli1, the expression of which is fully dependent on Hh signaling in mouse but not in zebrafish. These results reveal a conserved requirement for cilia in transducing the activity of upstream regulators of Hh signaling but distinct phenotypic effects due to differential regulation and differing roles of transcriptional mediators. PMID:19700616

  4. Biologically-based signal processing system applied to noise removal for signal extraction

    DOEpatents

    Fu, Chi Yung; Petrich, Loren I.

    2004-07-13

    The method and system described herein use a biologically-based signal processing system for noise removal for signal extraction. A wavelet transform may be used in conjunction with a neural network to imitate a biological system. The neural network may be trained using ideal data derived from physical principles or noiseless signals to determine to remove noise from the signal.

  5. Applied digital signal processing systems for vortex flowmeter with digital signal processing.

    PubMed

    Xu, Ke-Jun; Zhu, Zhi-Hai; Zhou, Yang; Wang, Xiao-Fen; Liu, San-Shan; Huang, Yun-Zhi; Chen, Zhi-Yuan

    2009-02-01

    The spectral analysis is combined with digital filter to process the vortex sensor signal for reducing the effect of disturbance at low frequency from pipe vibrations and increasing the turndown ratio. Using digital signal processing chip, two kinds of digital signal processing systems are developed to implement these algorithms. One is an integrative system, and the other is a separated system. A limiting amplifier is designed in the input analog condition circuit to adapt large amplitude variation of sensor signal. Some technique measures are taken to improve the accuracy of the output pulse, speed up the response time of the meter, and reduce the fluctuation of the output signal. The experimental results demonstrate the validity of the digital signal processing systems.

  6. Measurand transient signal suppressor

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor)

    1994-01-01

    A transient signal suppressor for use in a controls system which is adapted to respond to a change in a physical parameter whenever it crosses a predetermined threshold value in a selected direction of increasing or decreasing values with respect to the threshold value and is sustained for a selected discrete time interval is presented. The suppressor includes a sensor transducer for sensing the physical parameter and generating an electrical input signal whenever the sensed physical parameter crosses the threshold level in the selected direction. A manually operated switch is provided for adapting the suppressor to produce an output drive signal whenever the physical parameter crosses the threshold value in the selected direction of increasing or decreasing values. A time delay circuit is selectively adjustable for suppressing the transducer input signal for a preselected one of a plurality of available discrete suppression time and producing an output signal only if the input signal is sustained for a time greater than the selected suppression time. An electronic gate is coupled to receive the transducer input signal and the timer output signal and produce an output drive signal for energizing a control relay whenever the transducer input is a non-transient signal which is sustained beyond the selected time interval.

  7. Signal propagation in cortical networks: a digital signal processing approach.

    PubMed

    Rodrigues, Francisco Aparecido; da Fontoura Costa, Luciano

    2009-01-01

    This work reports a digital signal processing approach to representing and modeling transmission and combination of signals in cortical networks. The signal dynamics is modeled in terms of diffusion, which allows the information processing undergone between any pair of nodes to be fully characterized in terms of a finite impulse response (FIR) filter. Diffusion without and with time decay are investigated. All filters underlying the cat and macaque cortical organization are found to be of low-pass nature, allowing the cortical signal processing to be summarized in terms of the respective cutoff frequencies (a high cutoff frequency meaning little alteration of signals through their intermixing). Several findings are reported and discussed, including the fact that the incorporation of temporal activity decay tends to provide more diversified cutoff frequencies. Different filtering intensity is observed for each community in those networks. In addition, the brain regions involved in object recognition tend to present the highest cutoff frequencies for both the cat and macaque networks.

  8. Signaling by STATs

    PubMed Central

    Ivashkiv, Lionel B; Hu, Xiaoyu

    2004-01-01

    A variety of cytokines and growth factors use the Janus kinase (Jak)–STAT signaling pathway to transmit extracellular signals to the nucleus. STATs (signal transducers and activators of transcription) are latent cytoplasmic transcription factors. There are seven mammalian STATs and they have critical, nonredundant roles in mediating cellular transcriptional responses to cytokines. The physiological roles of STATs have been elucidated by analysis of mice rendered deficient in STAT genes. STAT activation is regulated and can be modulated in a positive or negative fashion; it can be reprogrammed to drive different cellular responses. Several auto-regulatory and signaling crosstalk mechanisms for regulating Jak–STAT signaling have been described. Understanding and manipulation of the function of STATs will help in the development of therapeutic strategies for diseases that are regulated by cytokines. PMID:15225360

  9. Signaling by STATs.

    PubMed

    Ivashkiv, Lionel B; Hu, Xiaoyu

    2004-01-01

    A variety of cytokines and growth factors use the Janus kinase (Jak)-STAT signaling pathway to transmit extracellular signals to the nucleus. STATs (signal transducers and activators of transcription) are latent cytoplasmic transcription factors. There are seven mammalian STATs and they have critical, nonredundant roles in mediating cellular transcriptional responses to cytokines. The physiological roles of STATs have been elucidated by analysis of mice rendered deficient in STAT genes. STAT activation is regulated and can be modulated in a positive or negative fashion; it can be reprogrammed to drive different cellular responses. Several auto-regulatory and signaling crosstalk mechanisms for regulating Jak-STAT signaling have been described. Understanding and manipulation of the function of STATs will help in the development of therapeutic strategies for diseases that are regulated by cytokines.

  10. Bmp signaling mediates endoderm pouch morphogenesis by regulating Fgf signaling in zebrafish

    PubMed Central

    Swartz, Mary E.; McCarthy, Neil; Norrie, Jacqueline L.; Eberhart, Johann K.

    2016-01-01

    The endodermal pouches are a series of reiterated structures that segment the pharyngeal arches and help pattern the vertebrate face. Multiple pathways regulate the complex process of endodermal development, including the Bone morphogenetic protein (Bmp) pathway. However, the role of Bmp signaling in pouch morphogenesis is poorly understood. Using genetic and chemical inhibitor approaches, we show that pouch morphogenesis requires Bmp signaling from 10-18 h post-fertilization, immediately following gastrulation. Blocking Bmp signaling during this window results in morphological defects to the pouches and craniofacial skeleton. Using genetic chimeras we show that Bmp signals directly to the endoderm for proper morphogenesis. Time-lapse imaging and analysis of reporter transgenics show that Bmp signaling is necessary for pouch outpocketing via the Fibroblast growth factor (Fgf) pathway. Double loss-of-function analyses demonstrate that Bmp and Fgf signaling interact synergistically in craniofacial development. Collectively, our analyses shed light on the tissue and signaling interactions that regulate development of the vertebrate face. PMID:27122171

  11. To signal or not to signal: that should not be the question.

    PubMed

    Faw, Harold W

    2013-10-01

    The purpose of the present research was to examine rates of turn signal use, a positive and potentially valuable means by which drivers can communicate. A second purpose was to explore factors that might impact these rates, including the modeling influence of other drivers. A series of observations involving more than 5600 vehicles making turns were recorded at a variety of intersections in British Columbia, Canada. Though the occurrence of signal use varied widely, ranging from a low of 54% to a high of 95%, the overall rate was 76%. Drivers used turn signals significantly less often when making right as compared with left turns, when traffic volume was higher, and when a designated turning lane was provided. In addition, compared with drivers following another vehicle not using signals, those following a vehicle with turn signals on were significantly more likely to activate their turn signals, suggesting a possible modeling effect. Both internal and external influences on turn signal use by drivers were considered. External factors explored in this research included direction of turn, traffic volume, intersection configuration, and the example of other drivers. It was concluded that the practice of signaling turns merits more research attention, since consistent use of signals is a potential contributor to enhanced safety for all road users. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. The signaling helix: a common functional theme in diverse signaling proteins

    PubMed Central

    Anantharaman, Vivek; Balaji, S; Aravind, L

    2006-01-01

    Background The mechanism by which the signals are transmitted between receptor and effector domains in multi-domain signaling proteins is poorly understood. Results Using sensitive sequence analysis methods we identify a conserved helical segment of around 40 residues in a wide range of signaling proteins, including numerous sensor histidine kinases such as Sln1p, and receptor guanylyl cyclases such as the atrial natriuretic peptide receptor and nitric oxide receptors. We term this helical segment the signaling (S)-helix and present evidence that it forms a novel parallel coiled-coil element, distinct from previously known helical segments in signaling proteins, such as the Dimerization-Histidine phosphotransfer module of histidine kinases, the intra-cellular domains of the chemotaxis receptors, inter-GAF domain helical linkers and the α-helical HAMP module. Analysis of domain architectures allowed us to reconstruct the domain-neighborhood graph for the S-helix, which showed that the S-helix almost always occurs between two signaling domains. Several striking patterns in the domain neighborhood of the S-helix also became evident from the graph. It most often separates diverse N-terminal sensory domains from various C-terminal catalytic signaling domains such as histidine kinases, cNMP cyclase, PP2C phosphatases, NtrC-like AAA+ ATPases and diguanylate cyclases. It might also occur between two sensory domains such as PAS domains and occasionally between a DNA-binding HTH domain and a sensory domain. The sequence conservation pattern of the S-helix revealed the presence of a unique constellation of polar residues in the dimer-interface positions within the central heptad of the coiled-coil formed by the S-helix. Conclusion Combining these observations with previously reported mutagenesis studies on different S-helix-containing proteins we suggest that it functions as a switch that prevents constitutive activation of linked downstream signaling domains. However, upon

  13. Problem-Solving Test: Real-Time Polymerase Chain Reaction

    ERIC Educational Resources Information Center

    Szeberenyi, Jozsef

    2009-01-01

    Terms to be familiar with before you start to solve the test: polymerase chain reaction, DNA amplification, electrophoresis, breast cancer, "HER2" gene, genomic DNA, "in vitro" DNA synthesis, template, primer, Taq polymerase, 5[prime][right arrow]3[prime] elongation activity, 5[prime][right arrow]3[prime] exonuclease activity, deoxyribonucleoside…

  14. ACHP | ACHP Policy Statements

    Science.gov Websites

    Search skip specific nav links Home arrow The National Historic Preservation Program arrow ACHP Policy Statements ACHP Policy Statements ACHP Policy Statement on Controversial Commemorative Works ACHP Policy Statement on Historic Preservation and Community Revitalizations Policy Statement on the ACHP's Interaction

  15. ACHP | News | ACHP Issue Spotlight: Transmission Lines in the West

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow New Applicant Guidance for Unified Federal Review for Disaster Recovery New Applicant Guidance for Unified Federal Review for Disaster Recovery The ACHP announce the release of the Unified Federal Environmental and Historic Preservation Review Guide for

  16. ACHP | Recovery Act Section 106 Training

    Science.gov Websites

    Working with Section 106 Federal, State, & Tribal Programs Training & Education Publications Search skip specific nav links Home arrow Training and Education arrow Recovery Act Section 106 Training RECOVERY ACT SECTION 106 TRAINING 2009 Recovery Act Section 106 Seminar Schedule Registration Forms General

  17. ACHP | News

    Science.gov Websites

    Working with Section 106 Federal, State, & Tribal Programs Training & Education Publications Search skip specific nav links Home arrow News arrow October 21, 2013 ACHP Provides 106 Training to the BLM-ACHP partnership, the ACHP liaison to the BLM, Nancy Brown, provided the training free of

  18. ACHP | Heritage Tourism and the Federal Government: Summit II Proceedings

    Science.gov Websites

    Search skip specific nav links Home arrow Publications arrow Intro: Heritage Tourism and the Federal Government: Summit II—Report of Proceedings Heritage Tourism and the Federal Government: Summit II—Report Heritage tourism promotes the preservation of communities' historic resources, educates tourists and local

  19. ACHP | Heritage Tourism and the Federal Government: Northern New Mexico

    Science.gov Websites

    Publications Search skip specific nav links Home arrow Publications arrow Intro: Heritage Tourism and the Federal Government: Northern New Mexico Perspectives Heritage Tourism and the Federal Government: Northern information Heritage tourism offers a triple benefit to communities—it promotes the preservation of their

  20. Interrogative suggestibility and perceptual motor performance.

    PubMed

    Gudjonsson, G H

    1984-04-01

    This study investigates the relationship between interrogative suggestibility, as measured by the Gudjonsson Suggestibility Scale, and Arrow-Dot scores. The tendency of subjects (25 men and 25 women, mean age 30.2 yr.) to alter their answers once interpersonal pressure had been applied correlated significantly with poor Arrow-Dot Ego functioning.

  1. ACHP | News | ACHP Issue Spotlight: Transmission Lines in the West

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Announces GAO Report Calling for Improved Data on Historic Properties ACHP Announces GAO Report Calling for Improved Data on Historic Properties The U.S. Government Accountability Office (GAO) recently released a report entitled "Improved Data

  2. ACHP | News | Native Hawaiian Federal Interagency Working Group Created

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Native Hawaiian Federal Interagency Working Group Created Native Hawaiian Federal Interagency Working Group Created Improving consultations on unique issues involving Native Hawaiian organizations is the purpose of a new interagency working group established by the

  3. The Origin of Lightning.

    ERIC Educational Resources Information Center

    Weewish Tree, 1979

    1979-01-01

    A heavenly source gives an orphaned Cherokee boy 12 silver arrows and directs him to kill the chief of the cruel Manitos (spirits). When the boy fails in his mission, the angry Manitos turn him into lightning, condemning him to flash like his silver arrows across the skies forever. (DS)

  4. ROS-dependent signal transduction

    PubMed Central

    Reczek, Colleen R; Chandel, Navdeep S

    2014-01-01

    Reactive oxygen species (ROS) are no longer viewed as just a toxic by-product of mitochondrial respiration, but are now appreciated for their role in regulating a myriad of cellular signaling pathways. H2O2, a type of ROS, is a signaling molecule that confers target specificity through thiol oxidation. Although redox-dependent signaling has been implicated in numerous cellular processes, the mechanism by which the ROS signal is transmitted to its target protein in the face of highly reactive and abundant antioxidants is not fully understood. In this review of redox-signaling biology, we discuss the possible mechanisms for H2O2-dependent signal transduction. PMID:25305438

  5. On the relevance of source effects in geomagnetic pulsations for induction soundings

    NASA Astrophysics Data System (ADS)

    Neska, Anne; Tadeusz Reda, Jan; Leszek Neska, Mariusz; Petrovich Sumaruk, Yuri

    2018-03-01

    This study is an attempt to close a gap between recent research on geomagnetic pulsations and their usage as source signals in electromagnetic induction soundings (i.e., magnetotellurics, geomagnetic depth sounding, and magnetovariational sounding). The plane-wave assumption as a precondition for the proper performance of these methods is partly violated by the local nature of field line resonances which cause a considerable portion of pulsations at mid latitudes. It is demonstrated that and explained why in spite of this, the application of remote reference stations in quasi-global distances for the suppression of local correlated-noise effects in induction arrows is possible in the geomagnetic pulsation range. The important role of upstream waves and of the magnetic equatorial region for such applications is emphasized. Furthermore, the principal difference between application of reference stations for local transfer functions (which result in sounding curves and induction arrows) and for inter-station transfer functions is considered. The preconditions for the latter are much stricter than for the former. Hence a failure to estimate an inter-station transfer function to be interpreted in terms of electromagnetic induction, e.g., because of field line resonances, does not necessarily prohibit use of the station pair for a remote reference estimation of the impedance tensor.

  6. The Hedgehog Signal Induced Modulation of Bone Morphogenetic Protein Signaling: An Essential Signaling Relay for Urinary Tract Morphogenesis

    PubMed Central

    Nakagata, Naomi; Miyagawa, Shinichi; Suzuki, Kentaro; Kitazawa, Sohei; Yamada, Gen

    2012-01-01

    Background Congenital diseases of the urinary tract are frequently observed in infants. Such diseases present a number of developmental anomalies such as hydroureter and hydronephrosis. Although some genetically-modified mouse models of growth factor signaling genes reproduce urinary phenotypes, the pathogenic mechanisms remain obscure. Previous studies suggest that a portion of the cells in the external genitalia and bladder are derived from peri-cloacal mesenchymal cells that receive Hedgehog (Hh) signaling in the early developmental stages. We hypothesized that defects in such progenitor cells, which give rise to urinary tract tissues, may be a cause of such diseases. Methodology/Principal Findings To elucidate the pathogenic mechanisms of upper urinary tract malformations, we analyzed a series of Sonic hedgehog (Shh) deficient mice. Shh−/− displayed hydroureter and hydronephrosis phenotypes and reduced expression of several developmental markers. In addition, we suggested that Shh modulation at an early embryonic stage is responsible for such phenotypes by analyzing the Shh conditional mutants. Tissue contribution assays of Hh-responsive cells revealed that peri-cloacal mesenchymal cells, which received Hh signal secreted from cloacal epithelium, could contribute to the ureteral mesenchyme. Gain- and loss-of-functional mutants for Hh signaling revealed a correlation between Hh signaling and Bone morphogenetic protein (Bmp) signaling. Finally, a conditional ablation of Bmp receptor type IA (BmprIA) gene was examined in Hh-responsive cell lineages. This system thus made it possible to analyze the primary functions of the growth factor signaling relay. The defective Hh-to-Bmp signaling relay resulted in severe urinary tract phenotypes with a decrease in the number of Hh-responsive cells. Conclusions/Significance This study identified the essential embryonic stages for the pathogenesis of urinary tract phenotypes. These results suggested that Hh

  7. Signal Processing, Analysis, & Display

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

    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 signalsmore » 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.« less

  8. Negative feedback from maternal signals reduces false alarms by collectively signalling offspring.

    PubMed

    Hamel, Jennifer A; Cocroft, Reginald B

    2012-09-22

    Within animal groups, individuals can learn of a predator's approach by attending to the behaviour of others. This use of social information increases an individual's perceptual range, but can also lead to the propagation of false alarms. Error copying is especially likely in species that signal collectively, because the coordination required for collective displays relies heavily on social information. Recent evidence suggests that collective behaviour in animals is, in part, regulated by negative feedback. Negative feedback may reduce false alarms by collectively signalling animals, but this possibility has not yet been tested. We tested the hypothesis that negative feedback increases the accuracy of collective signalling by reducing the production of false alarms. In the treehopper Umbonia crassicornis, clustered offspring produce collective signals during predator attacks, advertising the predator's location to the defending mother. Mothers signal after evicting the predator, and we show that this maternal communication reduces false alarms by offspring. We suggest that maternal signals elevate offspring signalling thresholds. This is, to our knowledge, the first study to show that negative feedback can reduce false alarms by collectively behaving groups.

  9. Bmp signaling mediates endoderm pouch morphogenesis by regulating Fgf signaling in zebrafish.

    PubMed

    Lovely, C Ben; Swartz, Mary E; McCarthy, Neil; Norrie, Jacqueline L; Eberhart, Johann K

    2016-06-01

    The endodermal pouches are a series of reiterated structures that segment the pharyngeal arches and help pattern the vertebrate face. Multiple pathways regulate the complex process of endodermal development, including the Bone morphogenetic protein (Bmp) pathway. However, the role of Bmp signaling in pouch morphogenesis is poorly understood. Using genetic and chemical inhibitor approaches, we show that pouch morphogenesis requires Bmp signaling from 10-18 h post-fertilization, immediately following gastrulation. Blocking Bmp signaling during this window results in morphological defects to the pouches and craniofacial skeleton. Using genetic chimeras we show that Bmp signals directly to the endoderm for proper morphogenesis. Time-lapse imaging and analysis of reporter transgenics show that Bmp signaling is necessary for pouch outpocketing via the Fibroblast growth factor (Fgf) pathway. Double loss-of-function analyses demonstrate that Bmp and Fgf signaling interact synergistically in craniofacial development. Collectively, our analyses shed light on the tissue and signaling interactions that regulate development of the vertebrate face. © 2016. Published by The Company of Biologists Ltd.

  10. ROS-dependent signal transduction.

    PubMed

    Reczek, Colleen R; Chandel, Navdeep S

    2015-04-01

    Reactive oxygen species (ROS) are no longer viewed as just a toxic by-product of mitochondrial respiration, but are now appreciated for their role in regulating a myriad of cellular signaling pathways. H2O2, a type of ROS, is a signaling molecule that confers target specificity through thiol oxidation. Although redox-dependent signaling has been implicated in numerous cellular processes, the mechanism by which the ROS signal is transmitted to its target protein in the face of highly reactive and abundant antioxidants is not fully understood. In this review of redox-signaling biology, we discuss the possible mechanisms for H2O2-dependent signal transduction. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Analog Signal Correlating Using an Analog-Based Signal Conditioning Front End

    NASA Technical Reports Server (NTRS)

    Prokop, Norman; Krasowski, Michael

    2013-01-01

    This innovation is capable of correlating two analog signals by using an analog-based signal conditioning front end to hard-limit the analog signals through adaptive thresholding into a binary bit stream, then performing the correlation using a Hamming "similarity" calculator function embedded in a one-bit digital correlator (OBDC). By converting the analog signal into a bit stream, the calculation of the correlation function is simplified, and less hardware resources are needed. This binary representation allows the hardware to move from a DSP where instructions are performed serially, into digital logic where calculations can be performed in parallel, greatly speeding up calculations.

  12. Interactive Digital Signal Processor

    NASA Technical Reports Server (NTRS)

    Mish, W. H.

    1985-01-01

    Interactive Digital Signal Processor, IDSP, consists of set of time series analysis "operators" based on various algorithms commonly used for digital signal analysis. Processing of digital signal time series to extract information usually achieved by applications of number of fairly standard operations. IDSP excellent teaching tool for demonstrating application for time series operators to artificially generated signals.

  13. Nonconscious Influence of Masked Stimuli on Response Selection Is Limited to Concrete Stimulus-Response Associations

    ERIC Educational Resources Information Center

    Klapp, Stuart T.; Haas, Brian W.

    2005-01-01

    A pattern-masked arrow negatively biased the "free choice" between 2 manual responses or between 2 vocal responses. This apparently nonconscious influence occurred only when the free-choice trials were intermixed randomly with other trials that terminated in fully visible arrows, which directed a response of the same modality (manual vs. vocal) as…

  14. Teachers' Occupation-Specific Work-Family Conflict

    ERIC Educational Resources Information Center

    Cinamon, Rachel Gali; Rich, Yisrael; Westman, Mina

    2007-01-01

    To expand work-family conflict (WFC) research to specific occupations, this study investigated how work and family generic and occupation-specific stressors and support variables related to family interfering with work (F [right arrow] W) and work interfering with family (W [right arrow] F) among 230 Israeli high school teachers. Further expanding…

  15. Attention and Gaze Control in Picture Naming, Word Reading, and Word Categorizing

    ERIC Educational Resources Information Center

    Roelofs, Ardi

    2007-01-01

    The trigger for shifting gaze between stimuli requiring vocal and manual responses was examined. Participants were presented with picture-word stimuli and left- or right-pointing arrows. They vocally named the picture (Experiment 1), read the word (Experiment 2), or categorized the word (Experiment 3) and shifted their gaze to the arrow to…

  16. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow June 10, 2014 ACHP Joins Western States Tourism Western States Tourism Policy Council MOU June 9 in Colorado Springs, Colorado. Interior Secretary Sally promotion and tourism development. WGA Annual Meeting Day 1: President Obama, drought readiness, Secretary

  17. Extinction and Renewal of Pavlovian Modulation in Human Sequential Feature Positive Discrimination Learning

    ERIC Educational Resources Information Center

    Baeyens, Frank; Vansteenwegen, Debora; Beckers, Tom; Hermans, Dirk; Kerkhof, Ineke; De Ceulaer, Annick

    2005-01-01

    Using a conditioned suppression task, we investigated extinction and renewal of Pavlovian modulation in human sequential Feature Positive (FP) discrimination learning. In Experiment 1, in context a participants were first trained on two FP discriminations, X[right arrow]A+/A- and Y[right arrow]B+/B-. Extinction treatment was administered in the…

  18. ACHP | News | Native Hawaiian Federal Interagency Working Group Created

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Walla Walla Veterans Administration Medical Center Gets New Use Walla Walla Veterans Administration Medical Center Gets New Use Recently a historic preservation effort at the Walla Walla Veterans Administration Medical Center came to larger light through a

  19. 26 CFR 48.4161(b)-2 - Meaning of terms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... The term “bows” includes all articles made of flexible materials, that are designed to be equipped with a string and used for the propelling of arrows in the sport of archery (target shooting), or in hunting or fishing. (2) Arrows. The term “arrows” includes all articles designed or constructed to be...

  20. 26 CFR 48.4161(b)-2 - Meaning of terms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... The term “bows” includes all articles made of flexible materials, that are designed to be equipped with a string and used for the propelling of arrows in the sport of archery (target shooting), or in hunting or fishing. (2) Arrows. The term “arrows” includes all articles designed or constructed to be...

  1. ACHP | News | Grants Effectiveness Study Released

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Grants Effectiveness Study Released Preserve America Grants Effectiveness Study Released Preserve America grants fund interpretive signs, like these at the Congress and the general public. The study found that the program is being effective in addressing many

  2. Cognitive and Affective Benefits of an Animated Pedagogical Agent for Learning English as a Second Language

    ERIC Educational Resources Information Center

    Choi, Sunhee; Clark, Richard E.

    2006-01-01

    This study compared the use of an animated pedagogical agent (agent) with an electronic arrow and voice narration (arrow and voice) in a multimedia learning environment where 74 college level English as a Second Language (ESL) students learned English relative clauses. No significant differences in learning or performance were found between the…

  3. Arrows as Anchors: An Analysis of the Material Features of Electric Field Vector Arrows

    ERIC Educational Resources Information Center

    Gire, Elizabeth; Price, Edward

    2014-01-01

    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…

  4. The Hedgehog Signal Transduction Network

    PubMed Central

    Robbins, David J.; Fei, Dennis Liang; Riobo, Natalia A.

    2013-01-01

    Hedgehog (Hh) proteins regulate the development of a wide range of metazoan embryonic and adult structures, and disruption of Hh signaling pathways results in various human diseases. Here, we provide a comprehensive review of the signaling pathways regulated by Hh, consolidating data from a diverse array of organisms in a variety of scientific disciplines. Similar to the elucidation of many other signaling pathways, our knowledge of Hh signaling developed in a sequential manner centered on its earliest discoveries. Thus, our knowledge of Hh signaling has for the most part focused on elucidating the mechanism by which Hh regulates the Gli family of transcription factors, the so-called “canonical” Hh signaling pathway. However, in the past few years, numerous studies have shown that Hh proteins can also signal through Gli-independent mechanisms collectively referred to as “noncanonical” signaling pathways. Noncanonical Hh signaling is itself subdivided into two distinct signaling modules: (i) those not requiring Smoothened (Smo) and (ii) those downstream of Smo that do not require Gli transcription factors. Thus, Hh signaling is now proposed to occur through a variety of distinct context-dependent signaling modules that have the ability to crosstalk with one another to form an interacting, dynamic Hh signaling network. PMID:23074268

  5. Wnt signaling in cancer

    PubMed Central

    Zhan, T; Rindtorff, N; Boutros, M

    2017-01-01

    Wnt signaling is one of the key cascades regulating development and stemness, and has also been tightly associated with cancer. The role of Wnt signaling in carcinogenesis has most prominently been described for colorectal cancer, but aberrant Wnt signaling is observed in many more cancer entities. Here, we review current insights into novel components of Wnt pathways and describe their impact on cancer development. Furthermore, we highlight expanding functions of Wnt signaling for both solid and liquid tumors. We also describe current findings how Wnt signaling affects maintenance of cancer stem cells, metastasis and immune control. Finally, we provide an overview of current strategies to antagonize Wnt signaling in cancer and challenges that are associated with such approaches. PMID:27617575

  6. Error-proneness as a handicap signal.

    PubMed

    De Jaegher, Kris

    2003-09-21

    This paper describes two discrete signalling models in which the error-proneness of signals can serve as a handicap signal. In the first model, the direct handicap of sending a high-quality signal is not large enough to assure that a low-quality signaller will not send it. However, if the receiver sometimes mistakes a high-quality signal for a low-quality one, then there is an indirect handicap to sending a high-quality signal. The total handicap of sending such a signal may then still be such that a low-quality signaller would not want to send it. In the second model, there is no direct handicap of sending signals, so that nothing would seem to stop a signaller from always sending a high-quality signal. However, the receiver sometimes fails to detect signals, and this causes an indirect handicap of sending a high-quality signal that still stops the low-quality signaller of sending such a signal. The conditions for honesty are that the probability of an error of detection is higher for a high-quality than for a low-quality signal, and that the signaller who does not detect a signal adopts a response that is bad to the signaller. In both our models, we thus obtain the result that signal accuracy should not lie above a certain level in order for honest signalling to be possible. Moreover, we show that the maximal accuracy that can be achieved is higher the lower the degree of conflict between signaller and receiver. As well, we show that it is the conditions for honest signalling that may be constraining signal accuracy, rather than the signaller trying to make honest signals as effective as possible given receiver psychology, or the signaller adapting the accuracy of honest signals depending on his interests.

  7. Signal characteristics of electroseismic conversion

    NASA Astrophysics Data System (ADS)

    Peng, Rong; Di, Bangrang; Wei, Jianxin; Ding, Pinbo; Liu, Zichun; Guan, Bingyan; Huang, Shiqi

    2018-04-01

    Electric fields applying on the fluid-filled porous materials can induce small relative pore-fluid motions due to electroseismic conversions. In order to characterize the electroseismic propagation phenomena, we have designed an experimental apparatus to acquire the electroseismic (ES) signals. The electroseismic measurements on different samples have been conducted to confirm the origin of the recorded signals. We find that a strong acoustic signal generates around the electrode and affects the identification of ES signals. To further confirm and distinguish the ES signal as well as the acoustic signal around the electrode, we have analyzed records obtained with regular movements of the receiver, the sample and the source. Analysis has been made on the characteristics of the traveltime, polarity and frequency of ES signals. Our results show that the traveltime of ES signal relates to the distance between the rock sample and the receiver, the location of the exciting electrode has little impact on the traveltime. The applied electric field influences the polarity of ES signal, the polarity of ES signal reverses along with the changes of the electric field direction. While it has no polarity effects on the acoustic signal generated around the electrode. The frequency spectrum of ES signal is absolutely different with that of the acoustic signal generated around the electrode. The acoustic signal around the electrode has multiple dominant frequencies which are mainly in low-frequency range without being affected by the frequency of the electric field. The ES signal has only one dominant frequency which closely relates to the frequency of the electric field. The understanding of the signal characteristics on electroseismic conversion can contribute to a better application and interpretation of ES exploration.

  8. Noise-Riding Video Signal Threshold Generation Scheme for a Plurality of Video Signal Channels

    DTIC Science & Technology

    2007-02-12

    on the selected one signal channel to generate a new video signal threshold . The processing resource has an output to provide the new video signal threshold to the comparator circuit corresponding to the selected signal channel.

  9. System for producing chroma signals

    NASA Technical Reports Server (NTRS)

    Vorhaben, K. H.; Lipoma, P. C. (Inventor)

    1977-01-01

    A method for obtaining electronic chroma signals with a single scanning-type image device is described. A color multiplexed light signal is produced using an arrangement of dichroic filter stripes. In the particular system described, a two layer filter is used to color modulate external light which is then detected by an image pickup tube. The resulting time division multiplexed electronic signal from the pickup tube is converted by a decoder into a green color signal, and a single red-blue multiplexed signal, which is demultiplexed to produce red and blue color signals. The three primary color signals can be encoded as standard NTSC color signals.

  10. Quantitative measures for redox signaling.

    PubMed

    Pillay, Ché S; Eagling, Beatrice D; Driscoll, Scott R E; Rohwer, Johann M

    2016-07-01

    Redox signaling is now recognized as an important regulatory mechanism for a number of cellular processes including the antioxidant response, phosphokinase signal transduction and redox metabolism. While there has been considerable progress in identifying the cellular machinery involved in redox signaling, quantitative measures of redox signals have been lacking, limiting efforts aimed at understanding and comparing redox signaling under normoxic and pathogenic conditions. Here we have outlined some of the accepted principles for redox signaling, including the description of hydrogen peroxide as a signaling molecule and the role of kinetics in conferring specificity to these signaling events. Based on these principles, we then develop a working definition for redox signaling and review a number of quantitative methods that have been employed to describe signaling in other systems. Using computational modeling and published data, we show how time- and concentration- dependent analyses, in particular, could be used to quantitatively describe redox signaling and therefore provide important insights into the functional organization of redox networks. Finally, we consider some of the key challenges with implementing these methods. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Determination of the Michel parameters and the {tau} neutrino helicity in {tau} decay

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

    CLEO Collaboration

    1997-11-01

    Using the CLEO II detector at the Cornell Electron Storage Ring operated at {radical} (s) =10.6GeV, we have determined the Michel parameters {rho}, {xi}, and {delta} in {tau}{sup {minus_plus}}{r_arrow}l{sup {minus_plus}}{nu}{bar {nu}} decay as well as the {tau} neutrino helicity parameter h{sub {nu}{sub {tau}}} in {tau}{sup {minus_plus}}{r_arrow}{pi}{sup {minus_plus}}{pi}{sup 0}{nu} decay. From a data sample of 3.02{times}10{sup 6} produced {tau} pairs we analyzed events of the topologies e{sup +}e{sup {minus}}{r_arrow}{tau}{sup +}{tau}{sup {minus}}{r_arrow}(l{sup {plus_minus}}{nu}{bar {nu}})({pi}{sup {minus_plus}}{pi}{sup 0}{nu}) and e{sup +}e{sup {minus}}{r_arrow}{tau}{sup +}{tau}{sup {minus}}{r_arrow}({pi}{sup {plus_minus}}{pi}{sup 0}{bar {nu}})({pi}{sup {minus_plus}}{pi}{sup 0}{nu}). We obtain {rho}=0.747{rho}=0.747{plus_minus}0.010{plus_minus}0.006, {xi}=1.007{plus_minus}0.040{plus_minus}0.015, {xi}{delta}=0.745{plus_minus}0.026{plus_minus}0.009, and h{sub {nu}{sub {tau}}}={minus}0.995{plus_minus}0.010{plus_minus}0.003, where we have used the previouslymore » determined sign of h{sub {nu}{sub {tau}}} [ARGUS Collaboration, H. Albrecht {ital et al.}, Z. Phys. C {bold 58}, 61 (1993); Phys. Lett. B {bold 349}, 576 (1995)]. We also present the Michel parameters as determined from the electron and muon samples separately. All results are in agreement with the standard model V{minus}A interaction. {copyright} {ital 1997} {ital The American Physical Society}« less

  12. ACHP | Web Site Privacy Policy

    Science.gov Websites

    Search skip specific nav links Home arrow About ACHP arrow Web Site Privacy Policy ACHP Web Site Privacy be used after its purpose has been fulfilled. For questions on our Web site privacy policy, please contact the Web manager. Updated October 2, 2006 Return to Top

  13. 77 FR 11568 - Notice of Intent To Repatriate Cultural Items: U.S. Department of Defense, Army Corps of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... arrow-shaft smoother fragment, 2 arrow-shaft straighteners, 2 bear canines (badly decayed), 1 bird bone... trade beads, 1 bone comb, 2 bone fragments, 1 bone pin, 1 brass pendant, 2 carved bone fragments, 1 celt... claws, 1 eagle bone whistle, 2 flakes, 1 flesher, 9 glass beads, 1 Glycymeris fragment, 1 graver or...

  14. DOE Research and Development Accomplishments Website Policies/Important

    Science.gov Websites

    Links RSS Archive Videos XML DOE R&D Accomplishments DOE R&D Accomplishments searchQuery × Find searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics Stories Snapshots R&D Nuggets Database dropdown arrow Search Tag Cloud Browse Reports Database Help

  15. ACHP | News | Native Hawaiian Federal Interagency Working Group Created

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Job Opening at the ACHP in Federal Property Management The ACHP is now recruiting for the position of Assistant Director for Federal Property Management preservation issues across the country. The Assistant Director for Federal Property Management has direct line

  16. Look Here! The Development of Attentional Orienting to Symbolic Cues

    ERIC Educational Resources Information Center

    Jakobsen, Krisztina Varga; Frick, Janet E.; Simpson, Elizabeth A.

    2013-01-01

    Although much research has examined the development of orienting to social directional cues (e.g., eye gaze), little is known about the development of orienting to nonsocial directional cues, such as arrows. Arrow cues have been used in numerous studies as a means to study attentional orienting, but the development of children's understanding of…

  17. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow August 7 , 2012 First Lady Designates New Preserve America Steward First Lady of the United States Michelle Obama has signed a designation letter recognizing with Essex County to preserve, rehabilitate, and revitalize America's first county park, which dates to

  18. Podcast Effectiveness as Scaffolding Support for Students Enrolled in First-Semester General Chemistry Laboratories

    ERIC Educational Resources Information Center

    Powell, Mary Cynthia Barton

    2010-01-01

    Podcasts covering essential first-semester general chemistry laboratory techniques and central concepts that aid in experimental design or data processing were prepared and made available for students to access on an as-needed basis on iPhones [arrow right] or iPod touches [arrow right]. Research focused in three areas: the extent of podcast…

  19. Graphic Representation of Force in Secondary Education: Analysis and Alternative Educational Proposals.

    ERIC Educational Resources Information Center

    Jimenez-Valladares, Juan de Dios; Perales-Palacios, F. Javier

    2001-01-01

    When students are forming their ideas of what will eventually become the concept of force, the images of arrows in our standard diagrams carry with them unconscious attributes of direction of movement and so on. Describes how the use of a 'symbolic representation of interactions' with double-headed arrows avoids these unwanted messages being…

  20. ACHP | "The Section 106 Essentials" Course

    Science.gov Websites

    Working with Section 106 Federal, State, & Tribal Programs Training & Education Publications Search skip specific nav links Home arrow Training and Education arrow The Section 106 Training Courses SECTION 106 TRAINING COURSES Why choose the ACHP for Section 106 training? Up-to-the-minute regulatory

  1. ACHP |Partnering to Promote Heritage Tourism in Local Communities: Guidance

    Science.gov Websites

    Publications Search skip specific nav links Home arrow Heritage Tourism arrow Partnering to Promote Heritage Tourism in Local Communities: Guidance for Federal Agencies Partnering to Promote Heritage Tourism in historic places. Such tourism - heritage tourism -can result in a variety of tangible and intangible

  2. ACHP | Working Together to Build a More Inclusive Preservation Program

    Science.gov Websites

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

  3. ACHP | Working Together to Build a More Inclusive Preservation Program

    Science.gov Websites

    Search skip specific nav links Home arrow Inclusiveness arrow Joyce Barrett Interview Interview with community we inherit depends on people understanding that preserving the places that matter is about our respect the courses and degrees, but they are meaningless if not used to involve people] Can you tell us

  4. Attention, Exposure Duration, and Gaze Shifting in Naming Performance

    ERIC Educational Resources Information Center

    Roelofs, Ardi

    2011-01-01

    Two experiments are reported in which the role of attribute exposure duration in naming performance was examined by tracking eye movements. Participants were presented with color-word Stroop stimuli and left- or right-pointing arrows on different sides of a computer screen. They named the color attribute and shifted their gaze to the arrow to…

  5. Molecular Determinants Fundamental to Axon Regeneration after SCI

    DTIC Science & Technology

    2012-06-01

    gray arrow) and a 130kDa N-terminal processed neurocan fragment (black arrow) in chABC treated samples (Asher et. al., 2000). Zebrafish brain tissue...PTPRSREV: GTG TGT GTG CTG ATG AAG GTC GC (EXON 9). 275 bp product expected. We have also designed a forward primer in exon 6 with negative results

  6. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Winter Business Meeting Wrap-up Winter Business business meeting in San Francisco, California, with three days of engaging with preservationists on the rich history, landscapes, and architecture of San Francisco and exposes them to the field of heritage

  7. ACHP | Working Together to Build a More Inclusive Preservation Program

    Science.gov Websites

    Search skip specific nav links Home arrow Inclusiveness arrow Chinese Heritage in Boston Has Strong Advocates Chinese Heritage in Boston Has Strong Advocates As part of the ACHP initiative on building a more to the early immigrants who are buried there, the Society collaborated with students at UMass Boston

  8. Signal Processing and Interpretation Using Multilevel Signal Abstractions.

    DTIC Science & Technology

    1986-06-01

    mappings expressed in the Fourier domain. Pre- viously proposed causal analysis techniques for diagnosis are based on the analysis of intermediate data ...can be processed either as individual one-dimensional waveforms or as multichannel data 26 I P- - . . . ." " ." h9. for source detection and direction...microphone data . The signal processing for both spectral analysis of microphone signals and direc- * tion determination of acoustic sources involves

  9. Measurement of the {ital {tau}} Neutrino Helicity and Michel Parameters in Polarized {ital e}{sup +}{ital e}{sup -} Collisions

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

    Steiner, R.; Benvenuti, A.C.; Coller, J.A.

    1997-06-01

    We present a new measurement of the {tau} neutrino helicity h{sub {nu}{sub {tau}}} and the {tau} Michel parameters {rho} , {eta} , {xi} , and the product {delta}{xi} . The analysis exploits the highly polarized SLC electron beam to extract these quantities directly from a measurement of the {tau} decay spectra, using the 1993{endash}1995 SLD data sample of 4328 e{sup +}e{sup -}{r_arrow}Z{sup 0}{r_arrow}{tau}{sup +}{tau}{sup -} events. From the decays {tau}{r_arrow}{pi}{nu}{sub {tau}} and {tau}{r_arrow}{rho}{nu}{sub {tau}} we obtain a combined value h{sub {nu}{sub {tau}}}=-0.93{plus_minus}0.10{plus_minus} 0.04 . The leptonic decay channels yield combined values of {rho}=0.72{plus_minus}0.09{plus_minus}0.03 , {xi}=1.05{plus_minus}0.35{plus_minus}0.04 , and {delta}{xi}=0.88{plus_minus}0.27{plus_minus}0.04 . {copyright}more » {ital 1997} {ital The American Physical Society}« less

  10. Parallel optimization of signal detection in active magnetospheric signal injection experiments

    NASA Astrophysics Data System (ADS)

    Gowanlock, Michael; Li, Justin D.; Rude, Cody M.; Pankratius, Victor

    2018-05-01

    Signal detection and extraction requires substantial manual parameter tuning at different stages in the processing pipeline. Time-series data depends on domain-specific signal properties, necessitating unique parameter selection for a given problem. The large potential search space makes this parameter selection process time-consuming and subject to variability. We introduce a technique to search and prune such parameter search spaces in parallel and select parameters for time series filters using breadth- and depth-first search strategies to increase the likelihood of detecting signals of interest in the field of magnetospheric physics. We focus on studying geomagnetic activity in the extremely and very low frequency ranges (ELF/VLF) using ELF/VLF transmissions from Siple Station, Antarctica, received at Québec, Canada. Our technique successfully detects amplified transmissions and achieves substantial speedup performance gains as compared to an exhaustive parameter search. We present examples where our algorithmic approach reduces the search from hundreds of seconds down to less than 1 s, with a ranked signal detection in the top 99th percentile, thus making it valuable for real-time monitoring. We also present empirical performance models quantifying the trade-off between the quality of signal recovered and the algorithm response time required for signal extraction. In the future, improved signal extraction in scenarios like the Siple experiment will enable better real-time diagnostics of conditions of the Earth's magnetosphere for monitoring space weather activity.

  11. Interplay between sugar and hormone signaling pathways modulate floral signal transduction

    PubMed Central

    Matsoukas, Ianis G.

    2014-01-01

    NOMENCLATURE The following nomenclature will be used in this article: Names of genes are written in italicized upper-case letters, e.g., ABI4.Names of proteins are written in non-italicized upper-case letters, e.g., ABI4.Names of mutants are written in italicized lower-case letters, e.g., abi4. The juvenile-to-adult and vegetative-to-reproductive phase transitions are major determinants of plant reproductive success and adaptation to the local environment. Understanding the intricate molecular genetic and physiological machinery by which environment regulates juvenility and floral signal transduction has significant scientific and economic implications. Sugars are recognized as important regulatory molecules that regulate cellular activity at multiple levels, from transcription and translation to protein stability and activity. Molecular genetic and physiological approaches have demonstrated different aspects of carbohydrate involvement and its interactions with other signal transduction pathways in regulation of the juvenile-to-adult and vegetative-to-reproductive phase transitions. Sugars regulate juvenility and floral signal transduction through their function as energy sources, osmotic regulators and signaling molecules. Interestingly, sugar signaling has been shown to involve extensive connections with phytohormone signaling. This includes interactions with phytohormones that are also important for the orchestration of developmental phase transitions, including gibberellins, abscisic acid, ethylene, and brassinosteroids. This article highlights the potential roles of sugar-hormone interactions in regulation of floral signal transduction, with particular emphasis on Arabidopsis thaliana mutant phenotypes, and suggests possible directions for future research. PMID:25165468

  12. Interplay between sugar and hormone signaling pathways modulate floral signal transduction.

    PubMed

    Matsoukas, Ianis G

    2014-01-01

    NOMENCLATURE The following nomenclature will be used in this article: Names of genes are written in italicized upper-case letters, e.g., ABI4.Names of proteins are written in non-italicized upper-case letters, e.g., ABI4.Names of mutants are written in italicized lower-case letters, e.g., abi4. The juvenile-to-adult and vegetative-to-reproductive phase transitions are major determinants of plant reproductive success and adaptation to the local environment. Understanding the intricate molecular genetic and physiological machinery by which environment regulates juvenility and floral signal transduction has significant scientific and economic implications. Sugars are recognized as important regulatory molecules that regulate cellular activity at multiple levels, from transcription and translation to protein stability and activity. Molecular genetic and physiological approaches have demonstrated different aspects of carbohydrate involvement and its interactions with other signal transduction pathways in regulation of the juvenile-to-adult and vegetative-to-reproductive phase transitions. Sugars regulate juvenility and floral signal transduction through their function as energy sources, osmotic regulators and signaling molecules. Interestingly, sugar signaling has been shown to involve extensive connections with phytohormone signaling. This includes interactions with phytohormones that are also important for the orchestration of developmental phase transitions, including gibberellins, abscisic acid, ethylene, and brassinosteroids. This article highlights the potential roles of sugar-hormone interactions in regulation of floral signal transduction, with particular emphasis on Arabidopsis thaliana mutant phenotypes, and suggests possible directions for future research.

  13. To signal or not to signal? Chemical communication by urine-borne signals mirrors sexual conflict in crayfish

    PubMed Central

    2010-01-01

    Background Sexual selection theory predicts that females, being the limiting sex, invest less in courtship signals than males. However, when chemical signals are involved it is often the female that initiates mating by producing stimuli that inform about sex and/or receptivity. This apparent contradiction has been discussed in the literature as 'the female pheromone fallacy'. Because the release of chemical stimuli may not have evolved to elicit the male's courtship response, whether these female stimuli represent signals remains an open question. Using techniques to visualise and block release of urine, we studied the role of urine signals during fighting and mating interactions of crayfish (Pacifastacus leniusculus). Test individuals were blindfolded to exclude visual disturbance from dye release and artificial urine introduction. Results Staged female-male pairings during the reproductive season often resulted in male mating attempts. Blocking female urine release in such pairings prevented any male courtship behaviour. Artificial introduction of female urine re-established male mating attempts. Urine visualisation showed that female urine release coincides with aggressive behaviours but not with female submissive behaviour in reproductive interactions as well as in intersexual and intrasexual fights. In reproductive interactions, females predominately released urine during precopulatory aggression; males subsequently released significantly less urine during mating than in fights. Conclusions Urine-blocking experiments demonstrate that female urine contains sex-specific components that elicit male mating behaviour. The coincidence of chemical signalling and aggressive behaviour in both females and males suggests that urine release has evolved as an aggressive signal in both sexes of crayfish. By limiting urine release to aggressive behaviours in reproductive interactions females challenge their potential mating partners at the same time as they trigger a sexual

  14. Theoretical study of aerodynamic characteristics of wings having vortex flow

    NASA Technical Reports Server (NTRS)

    Reddy, C. S.

    1979-01-01

    The aerodynamic characteristics of slender wings having separation induced vortex flows are investigated by employing three different computer codes--free vortex sheet, quasi vortex lattice, and suction analogy methods. Their capabilities and limitations are examined, and modifications are discussed. Flat wings of different configurations: arrow, delta, and diamond shapes, as well as cambered delta wings, are studied. The effect of notch ratio on the load distributions and the longitudinal characteristics of a family of arrow and diamond wings is explored. The sectional lift coefficients and the accumulated span loadings are determined for an arrow wing and are seen to be unusual in comparison with the attached flow results. The theoretically predicted results are compared with the existing experimental values.

  15. Signal processing method and system for noise removal and signal extraction

    DOEpatents

    Fu, Chi Yung; Petrich, Loren

    2009-04-14

    A signal processing method and system combining smooth level wavelet pre-processing together with artificial neural networks all in the wavelet domain for signal denoising and extraction. Upon receiving a signal corrupted with noise, an n-level decomposition of the signal is performed using a discrete wavelet transform to produce a smooth component and a rough component for each decomposition level. The n.sup.th level smooth component is then inputted into a corresponding neural network pre-trained to filter out noise in that component by pattern recognition in the wavelet domain. Additional rough components, beginning at the highest level, may also be retained and inputted into corresponding neural networks pre-trained to filter out noise in those components also by pattern recognition in the wavelet domain. In any case, an inverse discrete wavelet transform is performed on the combined output from all the neural networks to recover a clean signal back in the time domain.

  16. 33 CFR 117.15 - Signals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... used to request the opening of the draw and to acknowledge that request shall be sound signals, visual signals, or radiotelephone communications described in this subpart. (3) Any of the means of signaling... by the requesting vessel. (c) Visual signals. (1) The visual signal to request the opening of a draw...

  17. Combining Absorption and Dispersion Signals to Improve Signal-to-noise for Rapid Scan EPR Imaging

    PubMed Central

    Tseitlin, Mark; Quine, Richard W.; Rinard, George A.; Eaton, Sandra S.; Eaton, Gareth R.

    2010-01-01

    Direct detection of the rapid scan EPR signal with quadrature detection and without automatic frequency control provides both the absorption and dispersion components of the signal. The use of a cross-loop resonator results in similar signal-to-noise in the two channels. The dispersion signal can be converted to an equivalent absorption signal by means of Kramers-Kronig relations. The converted signal is added to the directly-measured absorption signal. Since the noise in the two channels is not correlated, this procedure increases the signal-to-noise ratio of the resultant absorption signal by up to a factor of √2. The utility of this method was demonstrated for 2D spectral-spatial imaging of a phantom containing 3 tubes of LiPc with different oxygen concentrations and therefore different linewidths. PMID:20181505

  18. Detection test of wireless network signal strength and GPS positioning signal in underground pipeline

    NASA Astrophysics Data System (ADS)

    Li, Li; Zhang, Yunwei; Chen, Ling

    2018-03-01

    In order to solve the problem of selecting positioning technology for inspection robot in underground pipeline environment, the wireless network signal strength and GPS positioning signal testing are carried out in the actual underground pipeline environment. Firstly, the strength variation of the 3G wireless network signal and Wi-Fi wireless signal provided by China Telecom and China Unicom ground base stations are tested, and the attenuation law of these wireless signals along the pipeline is analyzed quantitatively and described. Then, the receiving data of the GPS satellite signal in the pipeline are tested, and the attenuation of GPS satellite signal under underground pipeline is analyzed. The testing results may be reference for other related research which need to consider positioning in pipeline.

  19. 33 CFR 117.15 - Signals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Signals. 117.15 Section 117.15... REGULATIONS General Requirements § 117.15 Signals. (a) General. (1) The operator of each vessel requesting a drawbridge to open shall signal the drawtender and the drawtender shall acknowledge that signal. The signal...

  20. 33 CFR 117.15 - Signals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Signals. 117.15 Section 117.15... REGULATIONS General Requirements § 117.15 Signals. (a) General. (1) The operator of each vessel requesting a drawbridge to open shall signal the drawtender and the drawtender shall acknowledge that signal. The signal...

  1. 33 CFR 117.15 - Signals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Signals. 117.15 Section 117.15... REGULATIONS General Requirements § 117.15 Signals. (a) General. (1) The operator of each vessel requesting a drawbridge to open shall signal the drawtender and the drawtender shall acknowledge that signal. The signal...

  2. 33 CFR 117.15 - Signals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Signals. 117.15 Section 117.15... REGULATIONS General Requirements § 117.15 Signals. (a) General. (1) The operator of each vessel requesting a drawbridge to open shall signal the drawtender and the drawtender shall acknowledge that signal. The signal...

  3. Non-Smad signaling pathways.

    PubMed

    Mu, Yabing; Gudey, Shyam Kumar; Landström, Maréne

    2012-01-01

    Transforming growth factor-beta (TGFβ) is a key regulator of cell fate during embryogenesis and has also emerged as a potent driver of the epithelial-mesenchymal transition during tumor progression. TGFβ signals are transduced by transmembrane type I and type II serine/threonine kinase receptors (TβRI and TβRII, respectively). The activated TβR complex phosphorylates Smad2 and Smad3, converting them into transcriptional regulators that complex with Smad4. TGFβ also uses non-Smad signaling pathways such as the p38 and Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) pathways to convey its signals. Ubiquitin ligase tumor necrosis factor (TNF)-receptor-associated factor 6 (TRAF6) and TGFβ-associated kinase 1 (TAK1) have recently been shown to be crucial for the activation of the p38 and JNK MAPK pathways. Other TGFβ-induced non-Smad signaling pathways include the phosphoinositide 3-kinase-Akt-mTOR pathway, the small GTPases Rho, Rac, and Cdc42, and the Ras-Erk-MAPK pathway. Signals induced by TGFβ are tightly regulated and specified by post-translational modifications of the signaling components, since they dictate the subcellular localization, activity, and duration of the signal. In this review, we discuss recent findings in the field of TGFβ-induced responses by non-Smad signaling pathways.

  4. Signal existence verification (SEV) for GPS low received power signal detection using the time-frequency approach.

    PubMed

    Jan, Shau-Shiun; Sun, Chih-Cheng

    2010-01-01

    The detection of low received power of global positioning system (GPS) signals in the signal acquisition process is an important issue for GPS applications. Improving the miss-detection problem of low received power signal is crucial, especially for urban or indoor environments. This paper proposes a signal existence verification (SEV) process to detect and subsequently verify low received power GPS signals. The SEV process is based on the time-frequency representation of GPS signal, and it can capture the characteristic of GPS signal in the time-frequency plane to enhance the GPS signal acquisition performance. Several simulations and experiments are conducted to show the effectiveness of the proposed method for low received power signal detection. The contribution of this work is that the SEV process is an additional scheme to assist the GPS signal acquisition process in low received power signal detection, without changing the original signal acquisition or tracking algorithms.

  5. DOE Research and Development Accomplishments Nobel Chemists Associated with

    Science.gov Websites

    the DOE and Predecessors RSS Archive Videos XML DOE R&D Accomplishments DOE R&D Accomplishments searchQuery × Find searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Blog Archive SC Stories Snapshots R&D Nuggets Database dropdown arrow Search Tag Cloud Browse

  6. Daniel Shechtman and Quasicrystals

    Science.gov Websites

    toolbox that included transmission electron microscopy, X-ray diffraction and neutron diffraction. The searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About Letters, Vol. 53, Issue 20: 1951-1953; November 12, 1984 Nuclear γ-ray resonance observations in an

  7. ACHP | News | Preservation: One Key to Salvation for Cities and History

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Preservation: One Key to Salvation for Cities and History Preservation: One Key to Salvation for Cities and History The following is an article by ACHP October 10, 2002. Preservation Is One Key to Salvation for Cities and History John L. Nau, III Confederate

  8. ACHP | Fort Monroe Agreement Signed

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Fort Monroe Agreement Signed Fort Monroe Agreement Signed A historic agreement has been reached on a richly historic property, Fort Monroe, Virginia. Fort Programmatic Agreement (PA) that capped a lengthy and complex Section 106 consultation process led by the

  9. Thermochemical Process Integration, Scale-Up, and Piloting | Bioenergy |

    Science.gov Websites

    ; represented by spheres of hydrogen and carbon monoxide, then to "Gas Cleanup, Solids Removal, Reforming ; represented by a gasoline dispenser nozzle. A green arrow of "Fast Pyrolysis" and blue arrows for Distillation," and finally to "Fuels," represented by a gasoline dispenser nozzle Variety of

  10. Associative Learning of Discrimination with Masked Stimuli

    ERIC Educational Resources Information Center

    Marcos, Jose L.

    2007-01-01

    Great controversy exists on whether associative learning occurs without awareness. In Experiment 1, 31 participants received discrimination training by repeated presentations of two stimulus sequences (S1[subscript A] right arrow S2[subscript A], and S1[subscript B] right arrow S2[subscript B]), S1 being a masked stimulus. S2 were imperative…

  11. ACHP | News | ACHP Business Meeting Feb. 17 in Washington, D.C.

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Business Meeting Feb. 17 in Washington, D.C . ACHP Business Meeting Feb. 17 in Washington, D.C. The ACHP will host its winter business meeting three new members and present the chairman's award as well as address other business regarding renewable

  12. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow August 17, 2012 World Heritage Sites Report Released ), and the U.S. National Commission on UNESCO convened a symposium on U.S. World Heritage Sites at the University of Virginia, itself a World Heritage Site. The symposium was supported by the ACHP Alumni

  13. ACHP | Defense Department Compliance with NHPA

    Science.gov Websites

    NHPA: Section 202(a)(6) Evaluation Report Defense Department Compliance with the National Historic )(6) Evaluation Report is a preliminary step in helping the Department of Defense marshall its Search skip specific nav links Home arrow Publications arrow Intro: Defense Department Compliance with

  14. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow March 7, 2014 C&O Canal Trust, C&O Canal along the 184.5-mile Chesapeake & Ohio (C&O) Canal, received the Advisory Council on Historic . The Canal Quarters program was created and operates through a partnership with the C&O Canal

  15. EDITORIAL: Special section on signal transduction Special section on signal transduction

    NASA Astrophysics Data System (ADS)

    Shvartsman, Stanislav

    2012-08-01

    This special section of Physical Biology focuses on multiple aspects of signal transduction, broadly defined as the study of the mechanisms by which cells communicate with their environment. Mechanisms of cell communication involve detection of incoming signals, which can be chemical, mechanical or electromagnetic, relaying these signals to intracellular processes, such as cytoskeletal networks or gene expression systems, and, ultimately, converting these signals to responses such as cell differentiation or death. Given the multiscale nature of signal transduction systems, they must be studied at multiple levels, from the identities and structures of molecules comprising signal detection and interpretation networks, to the systems-level properties of these networks. The 11 papers in this special section illustrate some of the most exciting aspects of signal transduction research. The first two papers, by Marie-Anne Félix [1] and by Efrat Oron and Natalia Ivanova [2], focus on cell-cell interactions in developing tissues, using vulval patterning in worm and cell fate specification in mammalian embryos as prime examples of emergent cell behaviors. Next come two papers from the groups of Julio Saez-Rodriguez [3] and Kevin Janes [4]. These papers discuss how the causal relationships between multiple components of signaling systems can be inferred using multivariable statistical analysis of empirical data. An authoritative review by Zarnitsyna and Zhu [5] presents a detailed discussion of the sequence of signaling events involved in T-cell triggering. Once the structure and components of the signaling systems are determined, they can be modeled using approaches that have been successful in other physical sciences. As two examples of such approaches, reviews by Rubinstein [6] and Kholodenko [7], present reaction-diffusion models of cell polarization and thermodynamics-based models of gene regulation. An important class of models takes the form of enzymatic networks

  16. Poisson pre-processing of nonstationary photonic signals: Signals with equality between mean and variance.

    PubMed

    Poplová, Michaela; Sovka, Pavel; Cifra, Michal

    2017-01-01

    Photonic signals are broadly exploited in communication and sensing and they typically exhibit Poisson-like statistics. In a common scenario where the intensity of the photonic signals is low and one needs to remove a nonstationary trend of the signals for any further analysis, one faces an obstacle: due to the dependence between the mean and variance typical for a Poisson-like process, information about the trend remains in the variance even after the trend has been subtracted, possibly yielding artifactual results in further analyses. Commonly available detrending or normalizing methods cannot cope with this issue. To alleviate this issue we developed a suitable pre-processing method for the signals that originate from a Poisson-like process. In this paper, a Poisson pre-processing method for nonstationary time series with Poisson distribution is developed and tested on computer-generated model data and experimental data of chemiluminescence from human neutrophils and mung seeds. The presented method transforms a nonstationary Poisson signal into a stationary signal with a Poisson distribution while preserving the type of photocount distribution and phase-space structure of the signal. The importance of the suggested pre-processing method is shown in Fano factor and Hurst exponent analysis of both computer-generated model signals and experimental photonic signals. It is demonstrated that our pre-processing method is superior to standard detrending-based methods whenever further signal analysis is sensitive to variance of the signal.

  17. Poisson pre-processing of nonstationary photonic signals: Signals with equality between mean and variance

    PubMed Central

    Poplová, Michaela; Sovka, Pavel

    2017-01-01

    Photonic signals are broadly exploited in communication and sensing and they typically exhibit Poisson-like statistics. In a common scenario where the intensity of the photonic signals is low and one needs to remove a nonstationary trend of the signals for any further analysis, one faces an obstacle: due to the dependence between the mean and variance typical for a Poisson-like process, information about the trend remains in the variance even after the trend has been subtracted, possibly yielding artifactual results in further analyses. Commonly available detrending or normalizing methods cannot cope with this issue. To alleviate this issue we developed a suitable pre-processing method for the signals that originate from a Poisson-like process. In this paper, a Poisson pre-processing method for nonstationary time series with Poisson distribution is developed and tested on computer-generated model data and experimental data of chemiluminescence from human neutrophils and mung seeds. The presented method transforms a nonstationary Poisson signal into a stationary signal with a Poisson distribution while preserving the type of photocount distribution and phase-space structure of the signal. The importance of the suggested pre-processing method is shown in Fano factor and Hurst exponent analysis of both computer-generated model signals and experimental photonic signals. It is demonstrated that our pre-processing method is superior to standard detrending-based methods whenever further signal analysis is sensitive to variance of the signal. PMID:29216207

  18. Signal quality of endovascular electroencephalography

    NASA Astrophysics Data System (ADS)

    He, Bryan D.; Ebrahimi, Mosalam; Palafox, Leon; Srinivasan, Lakshminarayan

    2016-02-01

    Objective, Approach. A growing number of prototypes for diagnosing and treating neurological and psychiatric diseases are predicated on access to high-quality brain signals, which typically requires surgically opening the skull. Where endovascular navigation previously transformed the treatment of cerebral vascular malformations, we now show that it can provide access to brain signals with substantially higher signal quality than scalp recordings. Main results. While endovascular signals were known to be larger in amplitude than scalp signals, our analysis in rabbits borrows a standard technique from communication theory to show endovascular signals also have up to 100× better signal-to-noise ratio. Significance. With a viable minimally-invasive path to high-quality brain signals, patients with brain diseases could one day receive potent electroceuticals through the bloodstream, in the course of a brief outpatient procedure.

  19. Role of photoacoustics in optogalvanics

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

    Kumar, D.; McGlynn, S.P.

    1990-09-15

    Time-resolved laser optogalvanic (LOG) signals have been induced by pulsed laser excitation (l{ital s}{sub {ital j}}{r arrow}2{ital p}{sub {ital k}}, Paschen notation) of a {approximately}30 MHz radio-frequency (rf) discharge in neon at {approximately}5 torr. Dramatic changes of the shape/polarity of certain parts of the LOG signals occur when the rf excitation frequency is scanned over the electrical resonance peak of the plasma and the associated driving/detecting circuits. These effects are attributed to ionization rate changes (i.e., laser-induced alterations of the plasma conductivity), with concomitant variations in the plasma resonance characteristics. In addition to ionization rate changes, it is shown thatmore » photoacoustic (PA) effects also play a significant role in the generation of the LOG signal. Those parts of the LOG signal that are invariant with respect to the rf frequency are attributed to a PA effect. The similarity of LOG signal shapes from both rf and dc discharges suggests that photoacoustics play a similar role in the LOG effect in dc discharges. Contrary to common belief, most reported LOG signal profiles, ones produced by excitation to levels that do not lie close to the ionization threshold, appear to be totally mediated by the PA effect.« less

  20. Traffic signal synchronization.

    PubMed

    Huang, Ding-wei; Huang, Wei-neng

    2003-05-01

    The benefits of traffic signal synchronization are examined within the cellular automata approach. The microsimulations of traffic flow are obtained with different settings of signal period T and time delay delta. Both numerical results and analytical approximations are presented. For undersaturated traffic, the green-light wave solutions can be realized. For saturated traffic, the correlation among the traffic signals has no effect on the throughput. For oversaturated traffic, the benefits of synchronization are manifest only when stochastic noise is suppressed.

  1. BPSK Demodulation Using Digital Signal Processing

    NASA Technical Reports Server (NTRS)

    Garcia, Thomas R.

    1996-01-01

    A digital communications signal is a sinusoidal waveform that is modified by a binary (digital) information signal. The sinusoidal waveform is called the carrier. The carrier may be modified in amplitude, frequency, phase, or a combination of these. In this project a binary phase shift keyed (BPSK) signal is the communication signal. In a BPSK signal the phase of the carrier is set to one of two states, 180 degrees apart, by a binary (i.e., 1 or 0) information signal. A digital signal is a sampled version of a "real world" time continuous signal. The digital signal is generated by sampling the continuous signal at discrete points in time. The rate at which the signal is sampled is called the sampling rate (f(s)). The device that performs this operation is called an analog-to-digital (A/D) converter or a digitizer. The digital signal is composed of the sequence of individual values of the sampled BPSK signal. Digital signal processing (DSP) is the modification of the digital signal by mathematical operations. A device that performs this processing is called a digital signal processor. After processing, the digital signal may then be converted back to an analog signal using a digital-to-analog (D/A) converter. The goal of this project is to develop a system that will recover the digital information from a BPSK signal using DSP techniques. The project is broken down into the following steps: (1) Development of the algorithms required to demodulate the BPSK signal; (2) Simulation of the system; and (3) Implementation a BPSK receiver using digital signal processing hardware.

  2. Psychoacoustic processing of test signals

    NASA Astrophysics Data System (ADS)

    Kadlec, Frantisek

    2003-10-01

    For the quantitative evaluation of electroacoustic system properties and for psychoacoustic testing it is possible to utilize harmonic signals with fixed frequency, sweeping signals, random signals or their combination. This contribution deals with the design of various test signals with emphasis on audible perception. During the digital generation of signals, some additional undesirable frequency components and noise are produced, which are dependent on signal amplitude and sampling frequency. A mathematical analysis describes the origin of this distortion. By proper selection of signal frequency and amplitude it is possible to minimize those undesirable components. An additional step is to minimize the audible perception of this signal distortion by the application of additional noise (dither). For signals intended for listening tests a dither with triangular or Gaussian probability density function was found to be most effective. Signals modified this way may be further improved by the application of noise shaping, which transposes those undesirable products into frequency regions where they are perceived less, according to psychoacoustic principles. The efficiency of individual processing steps was confirmed both by measurements and by listening tests. [Work supported by the Czech Science Foundation.

  3. Hemodynamic signals in fNIRS.

    PubMed

    Hoshi, Y

    Near-infrared spectroscopy (NIRS) was originally designed for clinical monitoring of tissue oxygenation, and it has also been developed into a useful tool in neuroimaging studies, with the so-called functional NIRS (fNIRS). With NIRS, cerebral activation is detected by measuring the cerebral hemoglobin (Hb), where however, the precise correlation between NIRS signal and neural activity remains to be fully understood. This can in part be attributed to the situation that NIRS signals are inherently subject to contamination by signals arising from extracerebral tissue. In recent years, several approaches have been investigated to distinguish between NIRS signals originating in cerebral tissue and signals originating in extracerebral tissue. Selective measurements of cerebral Hb will enable a further evolution of fNIRS. This chapter is divided into six sections: first a summary of the basic theory of NIRS, NIRS signals arising in the activated areas, correlations between NIRS signals and fMRI signals, correlations between NIRS signals and neural activities, and the influence of a variety of extracerebral tissue on NIRS signals and approaches to this issue are reviewed. Finally, future prospects of fNIRS are described. © 2016 Elsevier B.V. All rights reserved.

  4. The Hippo signaling functions through the Notch signaling to regulate intrahepatic bile duct development in mammals.

    PubMed

    Wu, Nan; Nguyen, Quy; Wan, Ying; Zhou, Tiaohao; Venter, Julie; Frampton, Gabriel A; DeMorrow, Sharon; Pan, Duojia; Meng, Fanyin; Glaser, Shannon; Alpini, Gianfranco; Bai, Haibo

    2017-07-01

    The Hippo signaling pathway and the Notch signaling pathway are evolutionary conserved signaling cascades that have important roles in embryonic development of many organs. In murine liver, disruption of either pathway impairs intrahepatic bile duct development. Recent studies suggested that the Notch signaling receptor Notch2 is a direct transcriptional target of the Hippo signaling pathway effector YAP, and the Notch signaling is a major mediator of the Hippo signaling in maintaining biliary cell characteristics in adult mice. However, it remains to be determined whether the Hippo signaling pathway functions through the Notch signaling in intrahepatic bile duct development. We found that loss of the Hippo signaling pathway tumor suppressor Nf2 resulted in increased expression levels of the Notch signaling pathway receptor Notch2 in cholangiocytes but not in hepatocytes. When knocking down Notch2 on the background of Nf2 deficiency in mouse livers, the excessive bile duct development induced by Nf2 deficiency was suppressed by heterozygous and homozygous deletion of Notch2 in a dose-dependent manner. These results implicated that Notch signaling is one of the downstream effectors of the Hippo signaling pathway in regulating intrahepatic bile duct development.

  5. The Hippo signaling functions through the Notch signaling to regulate intrahepatic bile duct development in mammals

    PubMed Central

    Wu, Nan; Nguyen, Quy; Wan, Ying; Zhou, Tiaohao; Venter, Julie; Frampton, Gabriel A; DeMorrow, Sharon; Pan, Duojia; Meng, Fanyin; Glaser, Shannon; Alpini, Gianfranco; Bai, Haibo

    2018-01-01

    The Hippo signaling pathway and the Notch signaling pathway are evolutionary conserved signaling cascades that have important roles in embryonic development of many organs. In murine liver, disruption of either pathway impairs intrahepatic bile duct development. Recent studies suggested that the Notch signaling receptor Notch2 is a direct transcriptional target of the Hippo signaling pathway effector YAP, and the Notch signaling is a major mediator of the Hippo signaling in maintaining biliary cell characteristics in adult mice. However, it remains to be determined whether the Hippo signaling pathway functions through the Notch signaling in intrahepatic bile duct development. We found that loss of the Hippo signaling pathway tumor suppressor Nf2 resulted in increased expression levels of the Notch signaling pathway receptor Notch2 in cholangiocytes but not in hepatocytes. When knocking down Notch2 on the background of Nf2 deficiency in mouse livers, the excessive bile duct development induced by Nf2 deficiency was suppressed by heterozygous and homozygous deletion of Notch2 in a dose-dependent manner. These results implicated that Notch signaling is one of the downstream effectors of the Hippo signaling pathway in regulating intrahepatic bile duct development. PMID:28581486

  6. Signal quality and Bayesian signal processing in neurofeedback based on real-time fMRI.

    PubMed

    Koush, Yury; Zvyagintsev, Mikhail; Dyck, Miriam; Mathiak, Krystyna A; Mathiak, Klaus

    2012-01-02

    Real-time fMRI allows analysis and visualization of the brain activity online, i.e. within one repetition time. It can be used in neurofeedback applications where subjects attempt to control an activation level in a specified region of interest (ROI) of their brain. The signal derived from the ROI is contaminated with noise and artifacts, namely with physiological noise from breathing and heart beat, scanner drift, motion-related artifacts and measurement noise. We developed a Bayesian approach to reduce noise and to remove artifacts in real-time using a modified Kalman filter. The system performs several signal processing operations: subtraction of constant and low-frequency signal components, spike removal and signal smoothing. Quantitative feedback signal quality analysis was used to estimate the quality of the neurofeedback time series and performance of the applied signal processing on different ROIs. The signal-to-noise ratio (SNR) across the entire time series and the group event-related SNR (eSNR) were significantly higher for the processed time series in comparison to the raw data. Applied signal processing improved the t-statistic increasing the significance of blood oxygen level-dependent (BOLD) signal changes. Accordingly, the contrast-to-noise ratio (CNR) of the feedback time series was improved as well. In addition, the data revealed increase of localized self-control across feedback sessions. The new signal processing approach provided reliable neurofeedback, performed precise artifacts removal, reduced noise, and required minimal manual adjustments of parameters. Advanced and fast online signal processing algorithms considerably increased the quality as well as the information content of the control signal which in turn resulted in higher contingency in the neurofeedback loop. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Cooperative ethylene receptor signaling

    PubMed Central

    Liu, Qian; Wen, Chi-Kuang

    2012-01-01

    The gaseous plant hormone ethylene is perceived by a family of five ethylene receptor members in the dicotyledonous model plant Arabidopsis. Genetic and biochemical studies suggest that the ethylene response is suppressed by ethylene receptor complexes, but the biochemical nature of the receptor signal is unknown. Without appropriate biochemical measures to trace the ethylene receptor signal and quantify the signal strength, the biological significance of the modulation of ethylene responses by multiple ethylene receptors has yet to be fully addressed. Nevertheless, the ethylene receptor signal strength can be reflected by degrees in alteration of various ethylene response phenotypes and in expression levels of ethylene-inducible genes. This mini-review highlights studies that have advanced our understanding of cooperative ethylene receptor signaling. PMID:22827938

  8. 49 CFR 236.514 - Interconnection of cab signal system with roadway signal system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Interconnection of cab signal system with roadway signal system. 236.514 Section 236.514 Transportation Other Regulations Relating to Transportation... GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES...

  9. SIG. Signal Processing, Analysis, & Display

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

    Hernandez, J.; Lager, D.; Azevedo, S.

    1992-01-22

    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 includingmore » 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.« less

  10. SIG. Signal Processing, Analysis, & Display

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

    Hernandez, J.; Lager, D.; Azevedo, S.

    1992-01-22

    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 includingmore » 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.« less

  11. Overcoming low-alignment signal contrast induced alignment failure by alignment signal enhancement

    NASA Astrophysics Data System (ADS)

    Lee, Byeong Soo; Kim, Young Ha; Hwang, Hyunwoo; Lee, Jeongjin; Kong, Jeong Heung; Kang, Young Seog; Paarhuis, Bart; Kok, Haico; de Graaf, Roelof; Weichselbaum, Stefan; Droste, Richard; Mason, Christopher; Aarts, Igor; de Boeij, Wim P.

    2016-03-01

    Overlay is one of the key factors which enables optical lithography extension to 1X node DRAM manufacturing. It is natural that accurate wafer alignment is a prerequisite for good device overlay. However, alignment failures or misalignments are commonly observed in a fab. There are many factors which could induce alignment problems. Low alignment signal contrast is one of the main issues. Alignment signal contrast can be degraded by opaque stack materials or by alignment mark degradation due to processes like CMP. This issue can be compounded by mark sub-segmentation from design rules in combination with double or quadruple spacer process. Alignment signal contrast can be improved by applying new material or process optimization, which sometimes lead to the addition of another process-step with higher costs. If we can amplify the signal components containing the position information and reduce other unwanted signal and background contributions then we can improve alignment performance without process change. In this paper we use ASML's new alignment sensor (as was introduced and released on the NXT:1980Di) and sample wafers with special stacks which can induce poor alignment signal to demonstrate alignment and overlay improvement.

  12. Calcium specificity signaling mechanisms in abscisic acid signal transduction in Arabidopsis guard cells

    PubMed Central

    Brandt, Benjamin; Munemasa, Shintaro; Wang, Cun; Nguyen, Desiree; Yong, Taiming; Yang, Paul G; Poretsky, Elly; Belknap, Thomas F; Waadt, Rainer; Alemán, Fernando; Schroeder, Julian I

    2015-01-01

    A central question is how specificity in cellular responses to the eukaryotic second messenger Ca2+ is achieved. Plant guard cells, that form stomatal pores for gas exchange, provide a powerful system for in depth investigation of Ca2+-signaling specificity in plants. In intact guard cells, abscisic acid (ABA) enhances (primes) the Ca2+-sensitivity of downstream signaling events that result in activation of S-type anion channels during stomatal closure, providing a specificity mechanism in Ca2+-signaling. However, the underlying genetic and biochemical mechanisms remain unknown. Here we show impairment of ABA signal transduction in stomata of calcium-dependent protein kinase quadruple mutant plants. Interestingly, protein phosphatase 2Cs prevent non-specific Ca2+-signaling. Moreover, we demonstrate an unexpected interdependence of the Ca2+-dependent and Ca2+-independent ABA-signaling branches and the in planta requirement of simultaneous phosphorylation at two key phosphorylation sites in SLAC1. We identify novel mechanisms ensuring specificity and robustness within stomatal Ca2+-signaling on a cellular, genetic, and biochemical level. DOI: http://dx.doi.org/10.7554/eLife.03599.001 PMID:26192964

  13. Subcellular Redox Signaling.

    PubMed

    Zhu, Liping; Lu, Yankai; Zhang, Jiwei; Hu, Qinghua

    2017-01-01

    Oxidative and antioxidative system of cells and tissues maintains a balanced state under physiological conditions. A disruption in this balance of redox status has been associated with numerous pathological processes. Reactive oxygen species (ROS) as a major redox signaling generates in a spatiotemporally dependent manner. Subcellular organelles such as mitochondria, endoplasmic reticulum, plasma membrane and nuclei contribute to the production of ROS. In addition to downstream effects of ROS signaling regulated by average ROS changes in cytoplasm, whether subcelluar ROS mediate biological effect(s) has drawn greater attentions. With the advance in redox-sensitive probes targeted to different subcellular compartments, the investigation of subcellular ROS signaling and its associated cellular function has become feasible. In this review, we discuss the subcellular ROS signaling, with particular focus on mechanisms of subcellular ROS production and its downstream effects.

  14. Seismic signals hard clipping overcoming

    NASA Astrophysics Data System (ADS)

    Olszowa, Paula; Sokolowski, Jakub

    2018-01-01

    In signal processing the clipping is understand as the phenomenon of limiting the signal beyond certain threshold. It is often related to overloading of a sensor. Two particular types of clipping are being recognized: soft and hard. Beyond the limiting value soft clipping reduces the signal real gain while the hard clipping stiffly sets the signal values at the limit. In both cases certain amount of signal information is lost. Obviously if one possess the model which describes the considered signal and the threshold value (which might be slightly more difficult to obtain in the soft clipping case), the attempt of restoring the signal can be made. Commonly it is assumed that the seismic signals take form of an impulse response of some specific system. This may lead to belief that the sine wave may be the most appropriate to fit in the clipping period. However, this should be tested. In this paper the possibility of overcoming the hard clipping in seismic signals originating from a geoseismic station belonging to an underground mine is considered. A set of raw signals will be hard-clipped manually and then couple different functions will be fitted and compared in terms of least squares. The results will be then analysed.

  15. 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).

  16. The Manhattan Project -- Its Story

    Science.gov Websites

    was based upon research at Berkeley Lab, the first electromagnetic plant began to take shape in 1943 direction of J. Robert Oppenheimer, was set up to design and fabricate the first atomic bombs. To do this searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About

  17. Steven Chu - Patents

    Science.gov Websites

    searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About , Steven; et. al.; May 3, 1988 An ion energy filter of the type useful in connection with secondary ion mass spectrometry is disclosed. The filter is composed of a stack of 20 thin metal plates, each plate

  18. Patents -- Robert Hofstadter

    Science.gov Websites

    blood stream of a patient. An X-ray picture of a blood vessel such as the coronary artery can be searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About exposure to nuclear radiation such as gamma rays, beta rays, protons, mesons, X-rays, etc. wherein said

  19. Ilya Prigogine, Chaos, and Dissipative Structures

    Science.gov Websites

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

  20. ACHP | News | Native Hawaiian Federal Interagency Working Group Created

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Heritage Tourism Gets Boost with House Vote Heritage Tourism Gets Boost with House Vote On July 22, 2014, the U.S. House of Representatives passed H.R. 4450 to tourism draw to the United States from people all over the world. "Brand USA" was established by

  1. The Use of Rockets as Military Weapons at the Siege of Kai Fung Foo in 1232 A.D

    NASA Technical Reports Server (NTRS)

    2004-01-01

    One of the earliest recorded instances of the use of rockets was as military weapons against the Mongols by the Chinese at the siege of Kai Fung Foo in 1232 A.D. An arrow with a tube of gunpowder produced an arrow of flying fire. The Mongol attackers fled in terror, even though the rockets were inaccurate and relatively harmless.

  2. Early Rockets

    NASA Image and Video Library

    2004-04-15

    One of the earliest recorded instances of the use of rockets was as military weapons against the Mongols by the Chinese at the siege of Kai Fung Foo in 1232 A.D. An arrow with a tube of gunpowder produced an arrow of flying fire. The Mongol attackers fled in terror, even though the rockets were inaccurate and relatively harmless.

  3. Hybrid: Passing

    Science.gov Websites

    accelerating or when additional power is needed, the gasoline engine and electric motor are both used to propel . The car is passing another vehicle. There are red arrows flowing from the gasoline engine to the front wheels. There are blue arrows flowing from the battery to the electric engine to the front wheels. Main

  4. ACHP | News | ACHP Issues Program Comment for Disposal of Navy vessels

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Issues Program Comment for Disposal of Navy vessels ACHP Issues Program Comment for Disposal of Navy vessels March 8, 2010 – The Advisory Council on Historic Preservation (ACHP) has issued a Program Comment, pursuant to 36 CFR 800.14(e), to the U.S. Navy

  5. ACHP | News | ACHP Issue Spotlight: Transmission Lines in the West

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow Start Planning for the 50th Anniversary Today Start Planning for the 50th Anniversary Today! May 2015 is the perfect time to start planning for 2016 -- the movement. Start thinking about your own community and what you can do to celebrate preservation. Here are a

  6. Photoacoustic signal and noise analysis for Si thin plate: signal correction in frequency domain.

    PubMed

    Markushev, D D; Rabasović, M D; Todorović, D M; Galović, S; Bialkowski, S E

    2015-03-01

    Methods for photoacoustic signal measurement, rectification, and analysis for 85 μm thin Si samples in the 20-20 000 Hz modulation frequency range are presented. Methods for frequency-dependent amplitude and phase signal rectification in the presence of coherent and incoherent noise as well as distortion due to microphone characteristics are presented. Signal correction is accomplished using inverse system response functions deduced by comparing real to ideal signals for a sample with well-known bulk parameters and dimensions. The system response is a piece-wise construction, each component being due to a particular effect of the measurement system. Heat transfer and elastic effects are modeled using standard Rosencweig-Gersho and elastic-bending theories. Thermal diffusion, thermoelastic, and plasmaelastic signal components are calculated and compared to measurements. The differences between theory and experiment are used to detect and correct signal distortion and to determine detector and sound-card characteristics. Corrected signal analysis is found to faithfully reflect known sample parameters.

  7. Karrikin and cyanohydrin smoke signals provide clues to new endogenous plant signaling compounds.

    PubMed

    Flematti, Gavin R; Waters, Mark T; Scaffidi, Adrian; Merritt, David J; Ghisalberti, Emilio L; Dixon, Kingsley W; Smith, Steven M

    2013-01-01

    Two new types of signaling compounds have been discovered in wildfire smoke due to their ability to stimulate seed germination. The first discovered were karrikins, which share some structural similarity with the strigolactone class of plant hormones, and both signal through a common F-box protein. However, karrikins and strigolactones operate through otherwise distinct signaling pathways, each distinguished by a specific α/β hydrolase protein. Genetic analysis suggests that plants contain endogenous compounds that signal specifically through the karrikin pathway. The other active compounds discovered in smoke are cyanohydrins that release germination-stimulating cyanide upon hydrolysis. Cyanohydrins occur widely in plants and have a role in defense against other organisms, but an additional role in endogenous cyanide signaling should also now be considered.

  8. Signal Transduction in Cancer

    PubMed Central

    Sever, Richard; Brugge, Joan S.

    2015-01-01

    SUMMARY Cancer is driven by genetic and epigenetic alterations that allow cells to overproliferate and escape mechanisms that normally control their survival and migration. Many of these alterations map to signaling pathways that control cell growth and division, cell death, cell fate, and cell motility, and can be placed in the context of distortions of wider signaling networks that fuel cancer progression, such as changes in the tumor microenvironment, angiogenesis, and inflammation. Mutations that convert cellular proto-oncogenes to oncogenes can cause hyperactivation of these signaling pathways, whereas inactivation of tumor suppressors eliminates critical negative regulators of signaling. An examination of the PI3K-Akt and Ras-ERK pathways illustrates how such alterations dysregulate signaling in cancer and produce many of the characteristic features of tumor cells. PMID:25833940

  9. The Evolution of Covert Signaling.

    PubMed

    Smaldino, Paul E; Flamson, Thomas J; McElreath, Richard

    2018-03-20

    Human sociality depends upon the benefits of mutual aid and extensive communication. However, diverse norms and preferences complicate mutual aid, and ambiguity in meaning hinders communication. Here we demonstrate that these two problems can work together to enhance cooperation through the strategic use of deliberately ambiguous signals: covert signaling. Covert signaling is the transmission of information that is accurately received by its intended audience but obscured when perceived by others. Such signals may allow coordination and enhanced cooperation while also avoiding the alienation or hostile reactions of individuals with different preferences. Although the empirical literature has identified potential mechanisms of covert signaling, such as encryption in humor, there is to date no formal theory of its dynamics. We introduce a novel mathematical model to assess when a covert signaling strategy will evolve, as well as how receiver attitudes coevolve with covert signals. Covert signaling plausibly serves an important function in facilitating within-group cooperative assortment by allowing individuals to pair up with similar group members when possible and to get along with dissimilar ones when necessary. This mechanism has broad implications for theories of signaling and cooperation, humor, social identity, political psychology, and the evolution of human cultural complexity.

  10. Signal Construction-Based Dispersion Compensation of Lamb Waves Considering Signal Waveform and Amplitude Spectrum Preservation

    PubMed Central

    Cai, Jian; Yuan, Shenfang; Wang, Tongguang

    2016-01-01

    The results of Lamb wave identification for the aerospace structures could be easily affected by the nonlinear-dispersion characteristics. In this paper, dispersion compensation of Lamb waves is of particular concern. Compared with the similar research works on the traditional signal domain transform methods, this study is based on signal construction from the viewpoint of nonlinear wavenumber linearization. Two compensation methods of linearly-dispersive signal construction (LDSC) and non-dispersive signal construction (NDSC) are proposed. Furthermore, to improve the compensation effect, the influence of the signal construction process on the other crucial signal properties, including the signal waveform and amplitude spectrum, is considered during the investigation. The linear-dispersion and non-dispersion effects are firstly analyzed. Then, after the basic signal construction principle is explored, the numerical realization of LDSC and NDSC is discussed, in which the signal waveform and amplitude spectrum preservation is especially regarded. Subsequently, associated with the delay-and-sum algorithm, LDSC or NDSC is employed for high spatial resolution damage imaging, so that the adjacent multi-damage or quantitative imaging capacity of Lamb waves can be strengthened. To verify the proposed signal construction and damage imaging methods, the experimental and numerical validation is finally arranged on the aluminum plates. PMID:28772366

  11. Signal Construction-Based Dispersion Compensation of Lamb Waves Considering Signal Waveform and Amplitude Spectrum Preservation.

    PubMed

    Cai, Jian; Yuan, Shenfang; Wang, Tongguang

    2016-12-23

    The results of Lamb wave identification for the aerospace structures could be easily affected by the nonlinear-dispersion characteristics. In this paper, dispersion compensation of Lamb waves is of particular concern. Compared with the similar research works on the traditional signal domain transform methods, this study is based on signal construction from the viewpoint of nonlinear wavenumber linearization. Two compensation methods of linearly-dispersive signal construction (LDSC) and non-dispersive signal construction (NDSC) are proposed. Furthermore, to improve the compensation effect, the influence of the signal construction process on the other crucial signal properties, including the signal waveform and amplitude spectrum, is considered during the investigation. The linear-dispersion and non-dispersion effects are firstly analyzed. Then, after the basic signal construction principle is explored, the numerical realization of LDSC and NDSC is discussed, in which the signal waveform and amplitude spectrum preservation is especially regarded. Subsequently, associated with the delay-and-sum algorithm, LDSC or NDSC is employed for high spatial resolution damage imaging, so that the adjacent multi-damage or quantitative imaging capacity of Lamb waves can be strengthened. To verify the proposed signal construction and damage imaging methods, the experimental and numerical validation is finally arranged on the aluminum plates.

  12. Signal Separation of Helicopter Radar Returns Using Wavelet-Based Sparse Signal Optimisation

    DTIC Science & Technology

    2016-10-01

    RR–0436 ABSTRACT A novel wavelet-based sparse signal representation technique is used to separate the main and tail rotor blade components of a...helicopter from the composite radar returns. The received signal consists of returns from the rotating main and tail rotor blades , the helicopter body...component signal com- prising of returns from the main body, the main and tail rotor hubs and blades . Temporal and Doppler characteristics of these

  13. Pulsatile Hormonal Signaling to Extracellular Signal-regulated Kinase

    PubMed Central

    Perrett, Rebecca M.; Voliotis, Margaritis; Armstrong, Stephen P.; Fowkes, Robert C.; Pope, George R.; Tsaneva-Atanasova, Krasimira; McArdle, Craig A.

    2014-01-01

    Gonadotropin-releasing hormone (GnRH) is secreted in brief pulses that stimulate synthesis and secretion of pituitary gonadotropin hormones and thereby mediate control of reproduction. It acts via G-protein-coupled receptors to stimulate effectors, including ERK. Information could be encoded in GnRH pulse frequency, width, amplitude, or other features of pulse shape, but the relative importance of these features is unknown. Here we examine this using automated fluorescence microscopy and mathematical modeling, focusing on ERK signaling. The simplest scenario is one in which the system is linear, and response dynamics are relatively fast (compared with the signal dynamics). In this case integrated system output (ERK activation or ERK-driven transcription) will be roughly proportional to integrated input, but we find that this is not the case. Notably, we find that relatively slow response kinetics lead to ERK activity beyond the GnRH pulse, and this reduces sensitivity to pulse width. More generally, we show that the slowing of response kinetics through the signaling cascade creates a system that is robust to pulse width. We, therefore, show how various levels of response kinetics synergize to dictate system sensitivity to different features of pulsatile hormone input. We reveal the mathematical and biochemical basis of a dynamic GnRH signaling system that is robust to changes in pulse amplitude and width but is sensitive to changes in receptor occupancy and frequency, precisely the features that are tightly regulated and exploited to exert physiological control in vivo. PMID:24482225

  14. 49 CFR 176.176 - Signals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Signals. 176.176 Section 176.176 Transportation... Class 1 (Explosive) Materials Handling Class 1 (explosive) Materials in Port § 176.176 Signals. When... exhibit the following signals: (a) By day, flag “B” (Bravo) of the international code of signals; and (b...

  15. 49 CFR 176.176 - Signals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Signals. 176.176 Section 176.176 Transportation... Class 1 (Explosive) Materials Handling Class 1 (explosive) Materials in Port § 176.176 Signals. When... exhibit the following signals: (a) By day, flag “B” (Bravo) of the international code of signals; and (b...

  16. 49 CFR 176.176 - Signals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Signals. 176.176 Section 176.176 Transportation... Class 1 (Explosive) Materials Handling Class 1 (explosive) Materials in Port § 176.176 Signals. When... exhibit the following signals: (a) By day, flag “B” (Bravo) of the international code of signals; and (b...

  17. 49 CFR 176.176 - Signals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Signals. 176.176 Section 176.176 Transportation... Class 1 (Explosive) Materials Handling Class 1 (explosive) Materials in Port § 176.176 Signals. When... exhibit the following signals: (a) By day, flag “B” (Bravo) of the international code of signals; and (b...

  18. 49 CFR 176.176 - Signals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Signals. 176.176 Section 176.176 Transportation... Class 1 (Explosive) Materials Handling Class 1 (explosive) Materials in Port § 176.176 Signals. When... exhibit the following signals: (a) By day, flag “B” (Bravo) of the international code of signals; and (b...

  19. Systemic signaling during plant defense.

    PubMed

    Kachroo, Aardra; Robin, Guillaume P

    2013-08-01

    Systemic acquired resistance (SAR) is a type of pathogen-induced broad-spectrum resistance in plants. During SAR, primary infection-induced rapid generation and transportation of mobile signal(s) 'prepare' the rest of the plant for subsequent infections. Several, seemingly unrelated, mobile chemical inducers of SAR have been identified, at least two of which function in a feed-back regulatory loop with a lipid transfer-like protein. Signal(s) perception in the systemic tissues relies on the presence of an intact cuticle, the waxy layer covering all aerial parts of the plant. SAR results in chromatin modifications, which prime systemic tissues for enhanced and rapid signaling derived from salicylic acid, which along with its signaling components is key for SAR induction. This review summarizes recent findings related to SAR signal generation, movement, and perception. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. SIG. Signal Processing, Analysis, & Display

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

    Hernandez, J.; Lager, D.; Azevedo, S.

    1992-01-22

    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 signalsmore » 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.« less

  1. MBA Quality Signals.

    ERIC Educational Resources Information Center

    Chapman, Randall S.

    1998-01-01

    A study identified quality signals for master's programs in business administration (MBAs). Traditional scholarly oriented academic signals are apparently not valued as such by external customer groups. MBA academic quality appears to be a multidimensional construct, with subdimensions of real-worldness; placement; student satisfaction; and…

  2. Optical signal processing

    NASA Astrophysics Data System (ADS)

    Vanderlugt, A.

    1993-07-01

    A quasi-realtime adaptive processing system was used to correct the multipath distortion found in wideband digital radios. The measured power spectral density of the input signal was used to adaptively select one of eight equalization filters which reduce the residual distortion to less than 3.6 dB even for the most severe channel distortion. A related adaptive system was used for signal excision in which we removed narrowband interference from wideband signals with minimum signal distortion. An 8x8 acousto-optic switch in a multimode fiber-optic system was built. Insertion loss is approximately 2-4 dB, signal-to-crosstalk ratio is better than 25 dB, and the reconfiguration time is 880 nsec. Short pulses were detected by using the Fresnel transform. Pulses as short as the theoretical limit of 20 nanoseconds were detected for this system, and separated by as little as 60 nanoseconds or by as much as 17 nanoseconds. All possible acousto-optic scanning configurations were considered and classified into four basic types. A consistent set of design relationships for each of the scanning configurations was developed and presented in both tabular and graphic forms from which a preliminary design is obtained.

  3. Bioelectric Signal Measuring System

    NASA Astrophysics Data System (ADS)

    Guadarrama-Santana, A.; Pólo-Parada, L.; García-Valenzuela, A.

    2015-01-01

    We describe a low noise measuring system based on interdigitated electrodes for sensing bioelectrical signals. The system registers differential voltage measurements in order of microvolts. The base noise during measurements was in nanovolts and thus, the sensing signals presented a very good signal to noise ratio. An excitation voltage of 1Vrms with 10 KHz frequency was applied to an interdigitated capacitive sensor without a material under test and to a mirror device simultaneously. The output signals of both devices was then subtracted in order to obtain an initial reference value near cero volts and reduce parasitic capacitances due to the electronics, wiring and system hardware as well. The response of the measuring system was characterized by monitoring temporal bioelectrical signals in real time of biological materials such as embryo chicken heart cells and bovine suprarenal gland cells.

  4. Evolution and complexity: the double-edged sword.

    PubMed

    Miconi, Thomas

    2008-01-01

    We attempt to provide a comprehensive answer to the question of whether, and when, an arrow of complexity emerges in Darwinian evolution. We note that this expression can be interpreted in different ways, including a passive, incidental growth, or a pervasive bias towards complexification. We argue at length that an arrow of complexity does indeed occur in evolution, which can be most reasonably interpreted as the result of a passive trend rather than a driven one. What, then, is the role of evolution in the creation of this trend, and under which conditions will it emerge? In the later sections of this article we point out that when certain proper conditions (which we attempt to formulate in a concise form) are met, Darwinian evolution predictably creates a sustained trend of increase in maximum complexity (that is, an arrow of complexity) that would not be possible without it; but if they are not, evolution will not only fail to produce an arrow of complexity, but may actually prevent any increase in complexity altogether. We conclude that, with regard to the growth of complexity, evolution is very much a double-edged sword.

  5. Correction: Calcium specificity signaling mechanisms in abscisic acid signal transduction in Arabidopsis guard cells

    DOE PAGES

    Brandt, Benjamin; Munemasa, Shintaro; Wang, Cun; ...

    2015-07-20

    One central question is how specificity in cellular responses to the eukaryotic second messenger Ca 2+ is achieved. Plant guard cells, that form stomatal pores for gas exchange, provide a powerful system for in depth investigation of Ca 2+-signaling specificity in plants. In intact guard cells, abscisic acid (ABA) enhances (primes) the Ca 2+-sensitivity of downstream signaling events that result in activation of S-type anion channels during stomatal closure, providing a specificity mechanism in Ca 2+-signaling. However, the underlying genetic and biochemical mechanisms remain unknown. Here we show impairment of ABA signal transduction in stomata of calcium-dependent protein kinase quadruplemore » mutant plants. Interestingly, protein phosphatase 2Cs prevent non-specific Ca 2+-signaling. Moreover, we demonstrate an unexpected interdependence of the Ca 2+-dependent and Ca 2+-independent ABA-signaling branches and the in planta requirement of simultaneous phosphorylation at two key phosphorylation sites in SLAC1. We identify novel mechanisms ensuring specificity and robustness within stomatal Ca 2+-signaling on a cellular, genetic, and biochemical level.« less

  6. Correction: Calcium specificity signaling mechanisms in abscisic acid signal transduction in Arabidopsis guard cells

    DOE PAGES

    Brandt, Benjamin; Munemasa, Shintaro; Wang, Cun; ...

    2015-07-29

    A central question is how specificity in cellular responses to the eukaryotic second messenger Ca 2+ is achieved. Plant guard cells, that form stomatal pores for gas exchange, provide a powerful system for in depth investigation of Ca 2+-signaling specificity in plants. In intact guard cells, abscisic acid (ABA) enhances (primes) the Ca 2+-sensitivity of downstream signaling events that result in activation of S-type anion channels during stomatal closure, providing a specificity mechanism in Ca 2+-signaling. However, the underlying genetic and biochemical mechanisms remain unknown. Here we show impairment of ABA signal transduction in stomata of calcium-dependent protein kinase quadruplemore » mutant plants. Interestingly, protein phosphatase 2Cs prevent non-specific Ca 2+-signaling. Moreover, we demonstrate an unexpected interdependence of the Ca 2+-dependent and Ca 2+-independent ABA-signaling branches and the in planta requirement of simultaneous phosphorylation at two key phosphorylation sites in SLAC1. We identify novel mechanisms ensuring specificity and robustness within stomatal Ca 2+-signaling on a cellular, genetic, and biochemical level.« less

  7. Paracrine signaling in a bacterium.

    PubMed

    López, Daniel; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2009-07-15

    Cellular differentiation is triggered by extracellular signals that cause target cells to adopt a particular fate. Differentiation in bacteria typically involves autocrine signaling in which all cells in the population produce and respond to the same signal. Here we present evidence for paracrine signaling in bacterial populations-some cells produce a signal to which only certain target cells respond. Biofilm formation in Bacillus involves two centrally important signaling molecules, ComX and surfactin. ComX triggers the production of surfactin. In turn, surfactin causes a subpopulation of cells to produce an extracellular matrix. Cells that produced surfactin were themselves unable to respond to it. Likewise, once surfactin-responsive cells commenced matrix production, they no longer responded to ComX and could not become surfactin producers. Insensitivity to ComX was the consequence of the extracellular matrix as mutant cells unable to make matrix responded to both ComX and surfactin. Our results demonstrate that extracellular signaling was unidirectional, with one subpopulation producing a signal and a different subpopulation responding to it. Paracrine signaling in a bacterial population ensures the maintenance, over generations, of particular cell types even in the presence of molecules that would otherwise cause those cells to differentiate into other cell types.

  8. Reconstructing signals from noisy data with unknown signal and noise covariance.

    PubMed

    Oppermann, Niels; Robbers, Georg; Ensslin, Torsten A

    2011-10-01

    We derive a method to reconstruct Gaussian signals from linear measurements with Gaussian noise. This new algorithm is intended for applications in astrophysics and other sciences. The starting point of our considerations is the principle of minimum Gibbs free energy, which was previously used to derive a signal reconstruction algorithm handling uncertainties in the signal covariance. We extend this algorithm to simultaneously uncertain noise and signal covariances using the same principles in the derivation. The resulting equations are general enough to be applied in many different contexts. We demonstrate the performance of the algorithm by applying it to specific example situations and compare it to algorithms not allowing for uncertainties in the noise covariance. The results show that the method we suggest performs very well under a variety of circumstances and is indeed qualitatively superior to the other methods in cases where uncertainty in the noise covariance is present.

  9. DETECTOR FOR MODULATED AND UNMODULATED SIGNALS

    DOEpatents

    Patterson, H.H.; Webber, G.H.

    1959-08-25

    An r-f signal-detecting device is described, which is embodied in a compact coaxial circuit principally comprising a detecting crystal diode and a modulating crystal diode connected in parallel. Incoming modulated r-f signals are demodulated by the detecting crystal diode to furnish an audio input to an audio amplifier. The detecting diode will not, however, produce an audio signal from an unmodulated r-f signal. In order that unmodulated signals may be detected, such incoming signals have a locally produced audio signal superimposed on them at the modulating crystal diode and then the"induced or artificially modulated" signal is reflected toward the detecting diode which in the process of demodulation produces an audio signal for the audio amplifier.

  10. Brain Signal Variability is Parametrically Modifiable

    PubMed Central

    Garrett, Douglas D.; McIntosh, Anthony R.; Grady, Cheryl L.

    2014-01-01

    Moment-to-moment brain signal variability is a ubiquitous neural characteristic, yet remains poorly understood. Evidence indicates that heightened signal variability can index and aid efficient neural function, but it is not known whether signal variability responds to precise levels of environmental demand, or instead whether variability is relatively static. Using multivariate modeling of functional magnetic resonance imaging-based parametric face processing data, we show here that within-person signal variability level responds to incremental adjustments in task difficulty, in a manner entirely distinct from results produced by examining mean brain signals. Using mixed modeling, we also linked parametric modulations in signal variability with modulations in task performance. We found that difficulty-related reductions in signal variability predicted reduced accuracy and longer reaction times within-person; mean signal changes were not predictive. We further probed the various differences between signal variance and signal means by examining all voxels, subjects, and conditions; this analysis of over 2 million data points failed to reveal any notable relations between voxel variances and means. Our results suggest that brain signal variability provides a systematic task-driven signal of interest from which we can understand the dynamic function of the human brain, and in a way that mean signals cannot capture. PMID:23749875

  11. Quantifying ubiquitin signaling.

    PubMed

    Ordureau, Alban; Münch, Christian; Harper, J Wade

    2015-05-21

    Ubiquitin (UB)-driven signaling systems permeate biology, and are often integrated with other types of post-translational modifications (PTMs), including phosphorylation. Flux through such pathways is dictated by the fractional stoichiometry of distinct modifications and protein assemblies as well as the spatial organization of pathway components. Yet, we rarely understand the dynamics and stoichiometry of rate-limiting intermediates along a reaction trajectory. Here, we review how quantitative proteomic tools and enrichment strategies are being used to quantify UB-dependent signaling systems, and to integrate UB signaling with regulatory phosphorylation events, illustrated with the PINK1/PARKIN pathway. A key feature of ubiquitylation is that the identity of UB chain linkage types can control downstream processes. We also describe how proteomic and enzymological tools can be used to identify and quantify UB chain synthesis and linkage preferences. The emergence of sophisticated quantitative proteomic approaches will set a new standard for elucidating biochemical mechanisms of UB-driven signaling systems. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Quantifying Ubiquitin Signaling

    PubMed Central

    Ordureau, Alban; Münch, Christian; Harper, J. Wade

    2015-01-01

    Ubiquitin (UB)-driven signaling systems permeate biology, and are often integrated with other types of post-translational modifications (PTMs), most notably phosphorylation. Flux through such pathways is typically dictated by the fractional stoichiometry of distinct regulatory modifications and protein assemblies as well as the spatial organization of pathway components. Yet, we rarely understand the dynamics and stoichiometry of rate-limiting intermediates along a reaction trajectory. Here, we review how quantitative proteomic tools and enrichment strategies are being used to quantify UB-dependent signaling systems, and to integrate UB signaling with regulatory phosphorylation events. A key regulatory feature of ubiquitylation is that the identity of UB chain linkage types can control downstream processes. We also describe how proteomic and enzymological tools can be used to identify and quantify UB chain synthesis and linkage preferences. The emergence of sophisticated quantitative proteomic approaches will set a new standard for elucidating biochemical mechanisms of UB-driven signaling systems. PMID:26000850

  13. Compensation of the AKT signaling by ERK signaling in transgenic mice hearts overexpressing TRIM72

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

    Ham, Young-Mi, E-mail: youngmi_ham@hms.harvard.edu; Department of Cell Biology, Harvard Medical School, Boston, MA 02115; Mahoney, Sarah Jane

    The AKT and ERK signaling pathways are known to be involved in cell hypertrophy, proliferation, survival and differentiation. Although there is evidence for crosstalk between these two signaling pathways in cellulo, there is less evidence for cross talk in vivo. Here, we show that crosstalk between AKT and ERK signaling in the hearts of TRIM72-overexpressing transgenic mice (TRIM72-Tg) with alpha-MHC promoter regulates and maintains their heart size. TRIM72, a heart- and skeletal muscle-specific protein, downregulates AKT-mTOR signaling via IRS-1 degradation and reduces the size of rat cardiomyocytes and the size of postnatal TRIM72-Tg hearts. TRIM72 expression was upregulated by hypertrophicmore » inducers in cardiomyocytes, while IRS-1 was downregulated by IGF-1. TRIM72 specifically regulated IGF-1-dependent AKT-mTOR signaling, resulting in a reduction of the size of cardiomyocytes. Postnatal TRIM72-Tg hearts were smaller than control-treated hearts with inhibition of AKT-mTOR signaling. However, adult TRIM72-Tg hearts were larger than of control despite the suppression of AKT-mTOR signaling. Activation of ERK, PKC-α, and JNK were observed to be elevated in adult TRIM72-Tg, and these signals were mediated by ET-1 via the ET receptors A and B. Altogether, these results suggest that AKT signaling regulates cardiac hypertrophy in physiological conditions, and ERK signaling compensates for the absence of AKT signaling during TRIM72 overexpression, leading to pathological hypertrophy. -- Highlights: • TRIM72 inhibits AKT signaling through ubiquitination of IRS-1 in cardiac cells. • TRIM72 regulates the size of cardiac cells. • TRIM72 regulates size of postnatal TRIM72-overexpressing transgenic mice hearts. • Adult TRIM72-overexpressing transgenic mice hearts showed cardiac dysfunction. • Adult TRIM72 transgenic mice hearts showed higher expression of endothelin receptors.« less

  14. Emotion potentiates response activation and inhibition in masked priming

    PubMed Central

    Bocanegra, Bruno R.; Zeelenberg, René

    2012-01-01

    Previous studies have shown that emotion can have 2-fold effects on perception. At the object-level, emotional stimuli benefit from a stimulus-specific boost in visual attention at the relative expense of competing stimuli. At the visual feature-level, recent findings indicate that emotion may inhibit the processing of small visual details and facilitate the processing of coarse visual features. In the present study, we investigated whether emotion can boost the activation and inhibition of automatic motor responses that are generated prior to overt perception. To investigate this, we tested whether an emotional cue affects covert motor responses in a masked priming task. We used a masked priming paradigm in which participants responded to target arrows that were preceded by invisible congruent or incongruent prime arrows. In the standard paradigm, participants react faster, and commit fewer errors responding to the directionality of target arrows, when they are preceded by congruent vs. incongruent masked prime arrows (positive congruency effect, PCE). However, as prime-target SOAs increase, this effect reverses (negative congruency effect, NCE). These findings have been explained as evidence for an initial activation and a subsequent inhibition of a partial response elicited by the masked prime arrow. Our results show that the presentation of fearful face cues, compared to neutral face cues, increased the size of both the PCE and NCE, despite the fact that the primes were invisible. This is the first demonstration that emotion prepares an individual's visuomotor system for automatic activation and inhibition of motor responses in the absence of visual awareness. PMID:23162447

  15. Emotion potentiates response activation and inhibition in masked priming.

    PubMed

    Bocanegra, Bruno R; Zeelenberg, René

    2012-01-01

    Previous studies have shown that emotion can have 2-fold effects on perception. At the object-level, emotional stimuli benefit from a stimulus-specific boost in visual attention at the relative expense of competing stimuli. At the visual feature-level, recent findings indicate that emotion may inhibit the processing of small visual details and facilitate the processing of coarse visual features. In the present study, we investigated whether emotion can boost the activation and inhibition of automatic motor responses that are generated prior to overt perception. To investigate this, we tested whether an emotional cue affects covert motor responses in a masked priming task. We used a masked priming paradigm in which participants responded to target arrows that were preceded by invisible congruent or incongruent prime arrows. In the standard paradigm, participants react faster, and commit fewer errors responding to the directionality of target arrows, when they are preceded by congruent vs. incongruent masked prime arrows (positive congruency effect, PCE). However, as prime-target SOAs increase, this effect reverses (negative congruency effect, NCE). These findings have been explained as evidence for an initial activation and a subsequent inhibition of a partial response elicited by the masked prime arrow. Our results show that the presentation of fearful face cues, compared to neutral face cues, increased the size of both the PCE and NCE, despite the fact that the primes were invisible. This is the first demonstration that emotion prepares an individual's visuomotor system for automatic activation and inhibition of motor responses in the absence of visual awareness.

  16. Are visual cues helpful for virtual spatial navigation and spatial memory in patients with mild cognitive impairment or Alzheimer's disease?

    PubMed

    Cogné, Mélanie; Auriacombe, Sophie; Vasa, Louise; Tison, François; Klinger, Evelyne; Sauzéon, Hélène; Joseph, Pierre-Alain; N Kaoua, Bernard

    2018-05-01

    To evaluate whether visual cues are helpful for virtual spatial navigation and memory in Alzheimer's disease (AD) and patients with mild cognitive impairment (MCI). 20 patients with AD, 18 patients with MCI and 20 age-matched healthy controls (HC) were included. Participants had to actively reproduce a path that included 5 intersections with one landmark at each intersection that they had seen previously during a learning phase. Three cueing conditions for navigation were offered: salient landmarks, directional arrows and a map. A path without additional visual stimuli served as control condition. Navigation time and number of trajectory mistakes were recorded. With the presence of directional arrows, no significant difference was found between groups concerning the number of trajectory mistakes and navigation time. The number of trajectory mistakes did not differ significantly between patients with AD and patients with MCI on the path with arrows, the path with salient landmarks and the path with a map. There were significant correlations between the number of trajectory mistakes under the arrow condition and executive tests, and between the number of trajectory mistakes under the salient landmark condition and memory tests. Visual cueing such as directional arrows and salient landmarks appears helpful for spatial navigation and memory tasks in patients with AD and patients with MCI. This study opens new research avenues for neuro-rehabilitation, such as the use of augmented reality in real-life settings to support the navigational capabilities of patients with MCI and patients with AD. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  17. Wnt signaling potentiates nevogenesis

    PubMed Central

    Pawlikowski, Jeff S.; McBryan, Tony; van Tuyn, John; Drotar, Mark E.; Hewitt, Rachael N.; Maier, Andrea B.; King, Ayala; Blyth, Karen; Wu, Hong; Adams, Peter D.

    2013-01-01

    Cellular senescence is a stable proliferation arrest associated with an altered secretory pathway (senescence-associated secretory phenotype). Cellular senescence is also a tumor suppressor mechanism, to which both proliferation arrest and senescence-associated secretory phenotype are thought to contribute. The melanocytes within benign human nevi are a paradigm for tumor-suppressive senescent cells in a premalignant neoplasm. Here a comparison of proliferating and senescent melanocytes and melanoma cell lines by RNA sequencing emphasizes the importance of senescence-associated proliferation arrest in suppression of transformation. Previous studies showed that activation of the Wnt signaling pathway can delay or bypass senescence. Consistent with this, we present evidence that repression of Wnt signaling contributes to melanocyte senescence in vitro. Surprisingly, Wnt signaling is active in many senescent human melanocytes in nevi, and this is linked to histological indicators of higher proliferative and malignant potential. In a mouse, activated Wnt signaling delays senescence-associated proliferation arrest to expand the population of senescent oncogene-expressing melanocytes. These results suggest that Wnt signaling can potentiate nevogenesis in vivo by delaying senescence. Further, we suggest that activated Wnt signaling in human nevi undermines senescence-mediated tumor suppression and enhances the probability of malignancy. PMID:24043806

  18. Wnt signaling potentiates nevogenesis.

    PubMed

    Pawlikowski, Jeff S; McBryan, Tony; van Tuyn, John; Drotar, Mark E; Hewitt, Rachael N; Maier, Andrea B; King, Ayala; Blyth, Karen; Wu, Hong; Adams, Peter D

    2013-10-01

    Cellular senescence is a stable proliferation arrest associated with an altered secretory pathway (senescence-associated secretory phenotype). Cellular senescence is also a tumor suppressor mechanism, to which both proliferation arrest and senescence-associated secretory phenotype are thought to contribute. The melanocytes within benign human nevi are a paradigm for tumor-suppressive senescent cells in a premalignant neoplasm. Here a comparison of proliferating and senescent melanocytes and melanoma cell lines by RNA sequencing emphasizes the importance of senescence-associated proliferation arrest in suppression of transformation. Previous studies showed that activation of the Wnt signaling pathway can delay or bypass senescence. Consistent with this, we present evidence that repression of Wnt signaling contributes to melanocyte senescence in vitro. Surprisingly, Wnt signaling is active in many senescent human melanocytes in nevi, and this is linked to histological indicators of higher proliferative and malignant potential. In a mouse, activated Wnt signaling delays senescence-associated proliferation arrest to expand the population of senescent oncogene-expressing melanocytes. These results suggest that Wnt signaling can potentiate nevogenesis in vivo by delaying senescence. Further, we suggest that activated Wnt signaling in human nevi undermines senescence-mediated tumor suppression and enhances the probability of malignancy.

  19. Dynamic and diverse sugar signaling

    PubMed Central

    Li, Lei; Sheen, Jen

    2016-01-01

    Sugars fuel life and exert numerous regulatory actions that are fundamental to all life forms. There are two principal mechanisms underlie sugar “perception and signal transduction” in biological systems. Direct sensing and signaling is triggered via sugar-binding sensors with a broad range of affinity and specificity, whereas sugar-derived bioenergetic molecules and metabolites modulate signaling proteins and indirectly relay sugar signals. This review discusses the emerging sugar signals and potential sugar sensors discovered in plant systems. The findings leading to informative understanding of physiological regulation by sugars are considered and assessed. Comparative transcriptome analyses highlight the primary and dynamic sugar responses and reveal the convergent and specific regulators of key biological processes in the sugar-signaling network. PMID:27423125

  20. Heartbeat detection in multimodal physiological signals using signal quality assessment based on sample entropy.

    PubMed

    Singh, Omkar; Sunkaria, Ramesh Kumar

    2017-12-01

    This paper presents a novel technique to identify heartbeats in multimodal data using electrocardiogram (ECG) and arterial blood pressure (ABP) signals. Multiple physiological signals such as ECG, ABP, and Respiration are often recorded in parallel from the activity of heart. These signals generally possess related information as they are generated by the same physical system. The ECG and ABP correspond to the same phenomenon of contraction and relaxation activity of heart. Multiple signals acquired from various sensors are generally processed independently, thus discarding the information from other measurements. In the estimation of heart rate and heart rate variability, the R peaks are generally identified from ECG signal. Efficient detection of R-peaks in electrocardiogram (ECG) is a key component in the estimation of clinically relevant parameters from ECG. However, when the signal is severely affected by undesired artifacts, this becomes a challenging task. Sometimes in clinical environment, other physiological signals reflecting the cardiac activity such as ABP signal are also acquired simultaneously. Under the availability of such multimodal signals, the accuracy of R peak detection methods can be improved using sensor-fusion techniques. In the proposed method, the sample entropy (SampEn) is used as a metric for assessing the noise content in the physiological signal and the R peaks in ECG and the systolic peaks in ABP signals are fused together to enhance the efficiency of heartbeat detection. The proposed method was evaluated on the 100 records from the computing in cardiology challenge 2014 training data set. The performance parameters are: sensitivity (Se) and positive predictivity (PPV). The unimodal R peaks detector achieved: Se gross = 99.40%, PPV gross = 99.29%, Se average = 99.37%, PPV average = 99.29%. Similarly unimodal BP delineator achieved Se gross = 99.93%, PPV gross = 99.99%, Se average = 99.93%, PPV average = 99.99% whereas, the proposed

  1. Means and the Mean Value Theorem

    ERIC Educational Resources Information Center

    Merikoski, Jorma K.; Halmetoja, Markku; Tossavainen, Timo

    2009-01-01

    Let I be a real interval. We call a continuous function [mu] : I x I [right arrow] [Bold R] a proper mean if it is symmetric, reflexive, homogeneous, monotonic and internal. Let f : I [right arrow] [Bold R} be a differentiable and strictly convex or strictly concave function. If a, b [image omitted] I with a [not equal to] b, then there exists a…

  2. Sagitta

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    (the Arrow; abbrev. Sge, gen. Sagittae; area 80 sq. deg.) A northern constellation which lies between Vulpecula and Aquila, and culminates at midnight in mid-July. Its origin dates back at least to ancient Greece, where it was identified (by different authorities) with arrows belonging to Eros, Apollo and Hercules in Greek mythology. The brightest stars of Sagitta were cataloged by Ptolemy (c. AD...

  3. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow June 27, 2012 ACHP Rightsizing Task Force to Meet in Cleveland The ACHP's Rightsizing Task Force will be making a visit to Cleveland, Ohio, June 25-26 for a tour and a listening session and open meeting. The task force will host a public meeting on June 26 at

  4. Baird's beaked whale echolocation signals.

    PubMed

    Baumann-Pickering, Simone; Yack, Tina M; Barlow, Jay; Wiggins, Sean M; Hildebrand, John A

    2013-06-01

    Echolocation signals from Baird's beaked whales were recorded during visual and acoustic shipboard surveys of cetaceans in the California Current ecosystem and with autonomous, long-term recorders in the Southern California Bight. The preliminary measurement of the visually validated Baird's beaked whale echolocation signals from towed array data were used as a basis for identifying Baird's signals in the autonomous recorder data. Two distinct signal types were found, one being a beaked whale-like frequency modulated (FM) pulse, the other being a dolphin-like broadband click. The median FM inter-pulse interval was 230 ms. Both signal types showed a consistent multi-peak structure in their spectra with peaks at ~9, 16, 25, and 40 kHz. Depending on signal type, as well as recording aspect and distance to the hydrophone, these peaks varied in relative amplitude. The description of Baird's echolocation signals will allow for studies of their distribution and abundance using towed array data without associated visual sightings and from autonomous seafloor hydrophones.

  5. Brain signal variability is parametrically modifiable.

    PubMed

    Garrett, Douglas D; McIntosh, Anthony R; Grady, Cheryl L

    2014-11-01

    Moment-to-moment brain signal variability is a ubiquitous neural characteristic, yet remains poorly understood. Evidence indicates that heightened signal variability can index and aid efficient neural function, but it is not known whether signal variability responds to precise levels of environmental demand, or instead whether variability is relatively static. Using multivariate modeling of functional magnetic resonance imaging-based parametric face processing data, we show here that within-person signal variability level responds to incremental adjustments in task difficulty, in a manner entirely distinct from results produced by examining mean brain signals. Using mixed modeling, we also linked parametric modulations in signal variability with modulations in task performance. We found that difficulty-related reductions in signal variability predicted reduced accuracy and longer reaction times within-person; mean signal changes were not predictive. We further probed the various differences between signal variance and signal means by examining all voxels, subjects, and conditions; this analysis of over 2 million data points failed to reveal any notable relations between voxel variances and means. Our results suggest that brain signal variability provides a systematic task-driven signal of interest from which we can understand the dynamic function of the human brain, and in a way that mean signals cannot capture. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Signal timing on a shoestring

    DOT National Transportation Integrated Search

    2005-03-01

    The conventional approach to signal timing optimization and field deployment requires current traffic flow data, experience with optimization models, familiarity with the signal controller hardware, and knowledge of field operations including signal ...

  7. Signal timing on a shoestring.

    DOT National Transportation Integrated Search

    2005-03-01

    The conventional approach to signal timing optimization and field deployment requires current traffic flow data, experience with optimization models, familiarity with the signal controller hardware, and knowledge of field operations including signal ...

  8. Role of the third strand in the binding of proflavine and pt-proflavine to poly(rA).2poly(rU): a thermodynamic and kinetic study.

    PubMed

    García, Begoña; Leal, José M; Paiotta, Vittorio; Ruiz, Rebeca; Secco, Fernando; Venturini, Marcella

    2008-06-12

    The interactions of triple strands of poly(rA).2poly(rU) with proflavine (PR) and the proflavine cis-platinum derivative [{PtCl (tmen)} 2{NC 13H 7(NCH 2CH 2) 2}] (+) (PRPt) are examined at pH 7.0, T = 25 degrees C, and 0.2 M ionic strength by spectrophotometry, spectrofluorometry, circular dichroism, viscosimetry, stopped-flow, and T-jump relaxation techniques. The melting experiments demonstrate that both drugs tend to destabilize the triplex structure, although the PRPt effect is more relevant. By contrast, both drugs tend to slightly stabilize the duplex structure. The viscosity and circular dichroism measurements show that, at a low dye-to-polymer ratio ( C D/ C P), the binding is intercalative, whereas at high C D/ C P values, the external binding dominates. The binding kinetics and equilibria have been investigated over the C D/ C P region, where intercalation is operative. Both drugs bind to the RNA triplex according to the excluded site model. With PR, two kinetic effects have been observed, whereas with PRPt, only one has been observed. The results are interpreted according to the reaction schemes D + S right arrow over left arrow DS I, with PRPt, and D + S right arrow over left arrow DS I right arrow over left arrow DS II, with PR. The electrostatic contribution to the formation activation energy for DS I is similar (40%) for both systems. The results suggest that DS I is a partially intercalated species. Absence of the second step with PRPt is put down to groove interaction of the Pt-containing moiety, which prevents the PR residue from further penetration through the base pairs to form the fully intercalated complex, DS II. Comparison with the binding of the same drugs to the duplex reveals that the occupation of the major groove in poly(rA).2poly(rU) by the third strand plays a critical role in the kinetic behavior.

  9. Crystal structures and high-temperature phase-transitions in SrNdMRuO{sub 6} (M=Zn,Co,Mg,Ni) new double perovskites studied by symmetry-mode analysis

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

    Iturbe-Zabalo, E., E-mail: iturbe@ill.fr; Fisika Aplikatua II Saila, Zientzia eta Teknologia Fakultatea, UPV/EHU, P.O. Box 644, 48080 Bilbao; Igartua, J.M.

    2013-02-15

    Crystal structures of SrNdZnRuO{sub 6}, SrNdCoRuO{sub 6}, SrNdMgRuO{sub 6} and SrNdNiRuO{sub 6} double perovskites have been studied by X-ray, synchrotron radiation and neutron powder diffraction method, at different temperatures, and using the symmetry-mode analysis. All compounds adopt the monoclinic space group P2{sub 1}/n at room-temperature, and contain a completely ordered array of the tilted MO{sub 6} and RuO{sub 6} octahedra, whereas Sr/Nd cations are completely disordered. The analysis of the structures in terms of symmetry-adapted modes of the parent phase allows the identification of the modes responsible for the phase-transition. The high-temperature study (300-1250 K) has shown that the compoundsmore » present a temperature induced structural phase-transition: P2{sub 1}/n{yields}P4{sub 2}/n{yields}Fm3{sup Macron }m. - Graphical abstract: Representation of the dominant distortion modes of the symmetry mode decomposition of the room-temperature (P2{sub 1}/n), intermediate (P4{sub 2}/n) and cubic (Fm-3m) phase SrNdMRuO{sub 6} (M=Zn,Co,Mg,Ni), with respect to the parent phase Fm-3m. The dominant distortion modes are: in the monoclinic phase-GM{sub 4}{sup +} (blue arrow), X{sub 3}{sup +} (green arrow) and X{sub 5}{sup +} acting on A-site cations (red arrow); in the tetragonal phase-GM{sub 4}{sup +} (pink arrow), X{sub 3}{sup +} (light blue arrow) and X{sub 5}{sup +} acting on A-site cations (brown arrow). Highlights: Black-Right-Pointing-Pointer Structural study of four ruthenate double perovskites. Black-Right-Pointing-Pointer Room-temperature structural determination using symmetry-mode procedure. Black-Right-Pointing-Pointer Determination of temperature induced structural phase-transitions. Black-Right-Pointing-Pointer Symmetry adapted-mode analysis.« less

  10. A respiratory chain controlled signal transduction cascade in the mitochondrial intermembrane space mediates hydrogen peroxide signaling

    PubMed Central

    Patterson, Heide Christine; Gerbeth, Carolin; Thiru, Prathapan; Vögtle, Nora F.; Knoll, Marko; Shahsafaei, Aliakbar; Samocha, Kaitlin E.; Huang, Cher X.; Harden, Mark Michael; Song, Rui; Chen, Cynthia; Kao, Jennifer; Shi, Jiahai; Salmon, Wendy; Shaul, Yoav D.; Stokes, Matthew P.; Silva, Jeffrey C.; Bell, George W.; MacArthur, Daniel G.; Ruland, Jürgen; Meisinger, Chris; Lodish, Harvey F.

    2015-01-01

    Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) govern cellular homeostasis by inducing signaling. H2O2 modulates the activity of phosphatases and many other signaling molecules through oxidation of critical cysteine residues, which led to the notion that initiation of ROS signaling is broad and nonspecific, and thus fundamentally distinct from other signaling pathways. Here, we report that H2O2 signaling bears hallmarks of a regular signal transduction cascade. It is controlled by hierarchical signaling events resulting in a focused response as the results place the mitochondrial respiratory chain upstream of tyrosine-protein kinase Lyn, Lyn upstream of tyrosine-protein kinase SYK (Syk), and Syk upstream of numerous targets involved in signaling, transcription, translation, metabolism, and cell cycle regulation. The active mediators of H2O2 signaling colocalize as H2O2 induces mitochondria-associated Lyn and Syk phosphorylation, and a pool of Lyn and Syk reside in the mitochondrial intermembrane space. Finally, the same intermediaries control the signaling response in tissues and species responsive to H2O2 as the respiratory chain, Lyn, and Syk were similarly required for H2O2 signaling in mouse B cells, fibroblasts, and chicken DT40 B cells. Consistent with a broad role, the Syk pathway is coexpressed across tissues, is of early metazoan origin, and displays evidence of evolutionary constraint in the human. These results suggest that H2O2 signaling is under control of a signal transduction pathway that links the respiratory chain to the mitochondrial intermembrane space-localized, ubiquitous, and ancient Syk pathway in hematopoietic and nonhematopoietic cells. PMID:26438848

  11. A respiratory chain controlled signal transduction cascade in the mitochondrial intermembrane space mediates hydrogen peroxide signaling.

    PubMed

    Patterson, Heide Christine; Gerbeth, Carolin; Thiru, Prathapan; Vögtle, Nora F; Knoll, Marko; Shahsafaei, Aliakbar; Samocha, Kaitlin E; Huang, Cher X; Harden, Mark Michael; Song, Rui; Chen, Cynthia; Kao, Jennifer; Shi, Jiahai; Salmon, Wendy; Shaul, Yoav D; Stokes, Matthew P; Silva, Jeffrey C; Bell, George W; MacArthur, Daniel G; Ruland, Jürgen; Meisinger, Chris; Lodish, Harvey F

    2015-10-20

    Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) govern cellular homeostasis by inducing signaling. H2O2 modulates the activity of phosphatases and many other signaling molecules through oxidation of critical cysteine residues, which led to the notion that initiation of ROS signaling is broad and nonspecific, and thus fundamentally distinct from other signaling pathways. Here, we report that H2O2 signaling bears hallmarks of a regular signal transduction cascade. It is controlled by hierarchical signaling events resulting in a focused response as the results place the mitochondrial respiratory chain upstream of tyrosine-protein kinase Lyn, Lyn upstream of tyrosine-protein kinase SYK (Syk), and Syk upstream of numerous targets involved in signaling, transcription, translation, metabolism, and cell cycle regulation. The active mediators of H2O2 signaling colocalize as H2O2 induces mitochondria-associated Lyn and Syk phosphorylation, and a pool of Lyn and Syk reside in the mitochondrial intermembrane space. Finally, the same intermediaries control the signaling response in tissues and species responsive to H2O2 as the respiratory chain, Lyn, and Syk were similarly required for H2O2 signaling in mouse B cells, fibroblasts, and chicken DT40 B cells. Consistent with a broad role, the Syk pathway is coexpressed across tissues, is of early metazoan origin, and displays evidence of evolutionary constraint in the human. These results suggest that H2O2 signaling is under control of a signal transduction pathway that links the respiratory chain to the mitochondrial intermembrane space-localized, ubiquitous, and ancient Syk pathway in hematopoietic and nonhematopoietic cells.

  12. The impact of subliminal effect images in voluntary vs. stimulus-driven actions.

    PubMed

    Le Bars, Solène; Hsu, Yi-Fang; Waszak, Florian

    2016-11-01

    According to the ideomotor theory, actions are represented in terms of their sensory effects. In the current study we tested whether subliminal effect images influence action control (1) at early and/or late preparatory stages of (2) voluntary actions or stimulus-driven actions (3) with or without Stimulus-Response (S-R) compatibility. In Experiment 1, participants were presented at random with 50% of S-R compatible stimulus-driven action trials and 50% of voluntary action trials. The actions' effects (i.e. up- or down-pointing arrows) were presented subliminally before each action (i.e. a keypress). In voluntary actions, participants selected more often the action congruent with the prime when it was presented at long intervals before the action. Moreover they responded faster in prime-congruent than in prime-incongruent trials when primes were presented at short intervals before the action. In Experiment 2, participants were only presented with stimulus-driven action trials, with or without S-R compatibility. In stimulus-driven action trials with S-R compatibility (e.g., left-pointing arrow signaling a left keypress), subliminal action-effects did not generate any significant effect on RTs or error rates. On the other hand, in stimulus-driven action trials without S-R compatibility (e.g., letter "H" signaling a left keypress), participants were significantly faster in prime-congruent trials when primes were presented at the shortest time interval before the action. These results suggest that subliminal effect images facilitate voluntary action preparation on an early and a late level. Stimulus-driven action preparation is influenced on a late level only, and only if there is no compatibility between the stimulus and the motor response, that is when the response is not automatically triggered by the common properties existing between the stimulus and the required action. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  14. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  15. 46 CFR 109.503 - Emergency signals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Emergency signals. 109.503 Section 109.503 Shipping... Emergency Signals § 109.503 Emergency signals. (a) Emergency stations signals are established as follows: (1) The signal to man emergency stations is a rapid succession of short soundings of both the general...

  16. 46 CFR 109.503 - Emergency signals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Emergency signals. 109.503 Section 109.503 Shipping... Emergency Signals § 109.503 Emergency signals. (a) Emergency stations signals are established as follows: (1) The signal to man emergency stations is a rapid succession of short soundings of both the general...

  17. 46 CFR 109.503 - Emergency signals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Emergency signals. 109.503 Section 109.503 Shipping... Emergency Signals § 109.503 Emergency signals. (a) Emergency stations signals are established as follows: (1) The signal to man emergency stations is a rapid succession of short soundings of both the general...

  18. 46 CFR 109.503 - Emergency signals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Emergency signals. 109.503 Section 109.503 Shipping... Emergency Signals § 109.503 Emergency signals. (a) Emergency stations signals are established as follows: (1) The signal to man emergency stations is a rapid succession of short soundings of both the general...

  19. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  20. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  1. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  2. 46 CFR 109.503 - Emergency signals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Emergency signals. 109.503 Section 109.503 Shipping... Emergency Signals § 109.503 Emergency signals. (a) Emergency stations signals are established as follows: (1) The signal to man emergency stations is a rapid succession of short soundings of both the general...

  3. Progesterone-Mediated Non-Classical Signaling.

    PubMed

    Garg, Deepika; Ng, Sinnie Sin Man; Baig, K Maravet; Driggers, Paul; Segars, James

    2017-09-01

    Progesterone is essential for pregnancy maintenance and menstrual cycle regulation. Hormone action has been primarily ascribed to the well-characterized classical signaling pathway involving ligand binding, activation of nuclear progesterone receptors (PRs), and subsequent activation of genes containing progesterone response elements (PREs). Recent studies have revealed progesterone actions via non-classical signaling pathways, often mediated by non-genomic signaling. Progesterone signaling, in conjunction with growth factor signaling, impacts on the function of growth factors and regulates important physiological actions such as cell growth and remodeling, as well as apoptosis. This review focuses on non-classical progesterone signaling pathways, both including and excluding PR, and highlights how research in this area will provide a better understanding of progesterone actions and may inform novel therapeutic strategies. Copyright © 2017. Published by Elsevier Ltd.

  4. Engineering Cell-Cell Signaling

    PubMed Central

    Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R.

    2014-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling based on quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilizing synthetic cells, advanced ‘chassis’ and predictive modeling to engineer the form and function of living tissues. PMID:23856592

  5. Zinc Signals and Immunity.

    PubMed

    Maywald, Martina; Wessels, Inga; Rink, Lothar

    2017-10-24

    Zinc homeostasis is crucial for an adequate function of the immune system. Zinc deficiency as well as zinc excess result in severe disturbances in immune cell numbers and activities, which can result in increased susceptibility to infections and development of especially inflammatory diseases. This review focuses on the role of zinc in regulating intracellular signaling pathways in innate as well as adaptive immune cells. Main underlying molecular mechanisms and targets affected by altered zinc homeostasis, including kinases, caspases, phosphatases, and phosphodiesterases, will be highlighted in this article. In addition, the interplay of zinc homeostasis and the redox metabolism in affecting intracellular signaling will be emphasized. Key signaling pathways will be described in detail for the different cell types of the immune system. In this, effects of fast zinc flux, taking place within a few seconds to minutes will be distinguish from slower types of zinc signals, also designated as "zinc waves", and late homeostatic zinc signals regarding prolonged changes in intracellular zinc.

  6. Zinc Signals and Immunity

    PubMed Central

    Maywald, Martina; Wessels, Inga; Rink, Lothar

    2017-01-01

    Zinc homeostasis is crucial for an adequate function of the immune system. Zinc deficiency as well as zinc excess result in severe disturbances in immune cell numbers and activities, which can result in increased susceptibility to infections and development of especially inflammatory diseases. This review focuses on the role of zinc in regulating intracellular signaling pathways in innate as well as adaptive immune cells. Main underlying molecular mechanisms and targets affected by altered zinc homeostasis, including kinases, caspases, phosphatases, and phosphodiesterases, will be highlighted in this article. In addition, the interplay of zinc homeostasis and the redox metabolism in affecting intracellular signaling will be emphasized. Key signaling pathways will be described in detail for the different cell types of the immune system. In this, effects of fast zinc flux, taking place within a few seconds to minutes will be distinguish from slower types of zinc signals, also designated as “zinc waves”, and late homeostatic zinc signals regarding prolonged changes in intracellular zinc. PMID:29064429

  7. Segregation and manifestations of the mtDNA tRNA[sup Lys] A[r arrow]G[sup (8344)] mutation of myoclonus epilepsy and ragged-red fibers (MERRF) syndrome

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

    Larsson, N.G.; Tulinius, M.H.; Holme, E.

    1992-12-01

    The authors have studied the segregation and manifestations of the tRNA[sup Lys] A[r arrow]G[sup (8344)] mutation of mtDNA. Three unrelated patients with myoclonus epilepsy and ragged-red fibers (MERRF) syndrome were investigated, along with 30 of their maternal relatives. Mutated mtDNA was not always found in the offspring of women carrying the tRNA[sup Lys] mutation. Four women had 10%-33% of mutated mtDNA in lymphocytes, and no mutated mtDNA was found in 7 of their 14 investigated children. The presence of mutated mtDNA was excluded at a level of 3:1,000. Five women had a proportion of 43%-73% mutated mtDNA in lymphocytes, andmore » mutated mtDNA was found in all their 12 investigated children. This suggests that the risk for transmission of mutated mtDNA to the offspring increases if high levels are present in the mother and that, above a threshold level of 35%-40%, it is very likely that transmission will occur to all children. The three patients with MERRF syndrone had, in muscle, both 94%-96% mutated mtDNA and biochemical and histochemical evidence of a respiratory-chain dysfunction. Four relatives had a proportion of 61%-92% mutated mtDNA in muscle, and biochemical measurements showed a normal respiratory-chain function in muscle in all cases. These findings suggest that >92% of mtDNA with the tRNA[sup Lys] mutation in muscle is required to cause a respiratory-chain dysfunction that can be detected by biochemical methods. There was a positive correlation between the levels of mtDNA with the tRNA[sup Lys] mutation in lymphocytes and the levels in muscle, in all nine investigated cases. The levels of mutated mtDNA were higher in muscle than in lymphocytes in all cases. 30 refs., 3 figs., 5 tabs.« less

  8. Quinolizidine alkaloids from the curare adjuvant Clathrotropis glaucophylla.

    PubMed

    Sagen, Anne Lise; Gertsch, Jürg; Becker, Rita; Heilmann, Jörg; Sticher, Otto

    2002-12-01

    The bark of Clathrotropis glaucophylla (Fabaceae) is used as admixture of curare arrow poison by the Yanomami; Amerindians in Venezuela. A new quinolizidine alkaloid (QA), (-)-13alpha-hydroxy-15alpha-(1-hydroxyethyl)-anagyrine [(-)-clathrotropine], was isolated from the alkaloid extract of C. glaucophylla bark, together with eleven known QAs: (-)-anagyrine, (-)-thermopsine, (-)-baptifoline, (-)-epibaptifoline, (-)-rhombifoline, (-)-tinctorine, (-)-cytisine, (-)-N-methylcytisine, (-)-lupanine, (-)-6alpha-hydroxylupanine and (+)-5,6-dehydrolupanine. The isolation and structure elucidation were performed with the aid of chromatographic (TLC, HPLC and CC) and spectroscopic (UV and 1D/2D NMR) methods, and mass spectrometry. To our knowledge, this is the first time quinolizidine alkaloids have been isolated from an arrow poison ingredient. It is also the first report on Clathrotropis species being used for preparation of arrow poison.

  9. Measuring radio-signal power accurately

    NASA Technical Reports Server (NTRS)

    Goldstein, R. M.; Newton, J. W.; Winkelstein, R. A.

    1979-01-01

    Absolute value of signal power in weak radio signals is determined by computer-aided measurements. Equipment operates by averaging received signal over several-minute period and comparing average value with noise level of receiver previously calibrated.

  10. 33 CFR 118.130 - Fog signals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Fog signals. 118.130 Section 118... LIGHTING AND OTHER SIGNALS § 118.130 Fog signals. On waterways where visibility is frequently reduced due... more fog signals to warn the navigator of the presence of the bridge. The fog signals must conform to...

  11. 33 CFR 118.130 - Fog signals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Fog signals. 118.130 Section 118... LIGHTING AND OTHER SIGNALS § 118.130 Fog signals. On waterways where visibility is frequently reduced due... more fog signals to warn the navigator of the presence of the bridge. The fog signals must conform to...

  12. 33 CFR 118.130 - Fog signals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Fog signals. 118.130 Section 118... LIGHTING AND OTHER SIGNALS § 118.130 Fog signals. On waterways where visibility is frequently reduced due... more fog signals to warn the navigator of the presence of the bridge. The fog signals must conform to...

  13. 33 CFR 118.130 - Fog signals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Fog signals. 118.130 Section 118... LIGHTING AND OTHER SIGNALS § 118.130 Fog signals. On waterways where visibility is frequently reduced due... more fog signals to warn the navigator of the presence of the bridge. The fog signals must conform to...

  14. 33 CFR 118.130 - Fog signals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Fog signals. 118.130 Section 118... LIGHTING AND OTHER SIGNALS § 118.130 Fog signals. On waterways where visibility is frequently reduced due... more fog signals to warn the navigator of the presence of the bridge. The fog signals must conform to...

  15. Hybrid photonic signal processing

    NASA Astrophysics Data System (ADS)

    Ghauri, Farzan Naseer

    This thesis proposes research of novel hybrid photonic signal processing systems in the areas of optical communications, test and measurement, RF signal processing and extreme environment optical sensors. It will be shown that use of innovative hybrid techniques allows design of photonic signal processing systems with superior performance parameters and enhanced capabilities. These applications can be divided into domains of analog-digital hybrid signal processing applications and free-space---fiber-coupled hybrid optical sensors. The analog-digital hybrid signal processing applications include a high-performance analog-digital hybrid MEMS variable optical attenuator that can simultaneously provide high dynamic range as well as high resolution attenuation controls; an analog-digital hybrid MEMS beam profiler that allows high-power watt-level laser beam profiling and also provides both submicron-level high resolution and wide area profiling coverage; and all optical transversal RF filters that operate on the principle of broadband optical spectral control using MEMS and/or Acousto-Optic tunable Filters (AOTF) devices which can provide continuous, digital or hybrid signal time delay and weight selection. The hybrid optical sensors presented in the thesis are extreme environment pressure sensors and dual temperature-pressure sensors. The sensors employ hybrid free-space and fiber-coupled techniques for remotely monitoring a system under simultaneous extremely high temperatures and pressures.

  16. 46 CFR 169.815 - Emergency signals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Emergency signals. 169.815 Section 169.815 Shipping... Operations § 169.815 Emergency signals. (a) The station bill must set forth the various signals used for... vessels of 100 gross tons and over the following signals must be used. (1) The first alarm signal must be...

  17. 46 CFR 169.815 - Emergency signals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Emergency signals. 169.815 Section 169.815 Shipping... Operations § 169.815 Emergency signals. (a) The station bill must set forth the various signals used for... vessels of 100 gross tons and over the following signals must be used. (1) The first alarm signal must be...

  18. 46 CFR 169.815 - Emergency signals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Emergency signals. 169.815 Section 169.815 Shipping... Operations § 169.815 Emergency signals. (a) The station bill must set forth the various signals used for... vessels of 100 gross tons and over the following signals must be used. (1) The first alarm signal must be...

  19. Wnt Signaling in Cardiac Disease.

    PubMed

    Hermans, Kevin C M; Blankesteijn, W Matthijs

    2015-07-01

    Wnt signaling encompasses multiple and complex signaling cascades and is involved in many developmental processes such as tissue patterning, cell fate specification, and control of cell division. Consequently, accurate regulation of signaling activities is essential for proper embryonic development. Wnt signaling is mostly silent in the healthy adult organs but a reactivation of Wnt signaling is generally observed under pathological conditions. This has generated increasing interest in this pathway from a therapeutic point of view. In this review article, the involvement of Wnt signaling in cardiovascular development will be outlined, followed by its implication in myocardial infarct healing, cardiac hypertrophy, heart failure, arrhythmias, and atherosclerosis. The initial experiments not always offer consensus on the effects of activation or inactivation of the pathway, which may be attributed to (i) the type of cardiac disease, (ii) timing of the intervention, and (iii) type of cells that are targeted. Therefore, more research is needed to determine the exact implication of Wnt signaling in the conditions mentioned above to exploit it as a powerful therapeutic target. © 2015 American Physiological Society.

  20. The statistical mechanics of complex signaling networks: nerve growth factor signaling

    NASA Astrophysics Data System (ADS)

    Brown, K. S.; Hill, C. C.; Calero, G. A.; Myers, C. R.; Lee, K. H.; Sethna, J. P.; Cerione, R. A.

    2004-10-01

    The inherent complexity of cellular signaling networks and their importance to a wide range of cellular functions necessitates the development of modeling methods that can be applied toward making predictions and highlighting the appropriate experiments to test our understanding of how these systems are designed and function. We use methods of statistical mechanics to extract useful predictions for complex cellular signaling networks. A key difficulty with signaling models is that, while significant effort is being made to experimentally measure the rate constants for individual steps in these networks, many of the parameters required to describe their behavior remain unknown or at best represent estimates. To establish the usefulness of our approach, we have applied our methods toward modeling the nerve growth factor (NGF)-induced differentiation of neuronal cells. In particular, we study the actions of NGF and mitogenic epidermal growth factor (EGF) in rat pheochromocytoma (PC12) cells. Through a network of intermediate signaling proteins, each of these growth factors stimulates extracellular regulated kinase (Erk) phosphorylation with distinct dynamical profiles. Using our modeling approach, we are able to predict the influence of specific signaling modules in determining the integrated cellular response to the two growth factors. Our methods also raise some interesting insights into the design and possible evolution of cellular systems, highlighting an inherent property of these systems that we call 'sloppiness.'

  1. A survey of signal processing algorithms in brain-computer interfaces based on electrical brain signals.

    PubMed

    Bashashati, Ali; Fatourechi, Mehrdad; Ward, Rabab K; Birch, Gary E

    2007-06-01

    Brain-computer interfaces (BCIs) aim at providing a non-muscular channel for sending commands to the external world using the electroencephalographic activity or other electrophysiological measures of the brain function. An essential factor in the successful operation of BCI systems is the methods used to process the brain signals. In the BCI literature, however, there is no comprehensive review of the signal processing techniques used. This work presents the first such comprehensive survey of all BCI designs using electrical signal recordings published prior to January 2006. Detailed results from this survey are presented and discussed. The following key research questions are addressed: (1) what are the key signal processing components of a BCI, (2) what signal processing algorithms have been used in BCIs and (3) which signal processing techniques have received more attention?

  2. Orchestrating rapid long-distance signaling in plants with Ca2+ , ROS and electrical signals.

    PubMed

    Choi, Won-Gyu; Miller, Gad; Wallace, Ian; Harper, Jeffrey; Mittler, Ron; Gilroy, Simon

    2017-05-01

    Plants show a rapid systemic response to a wide range of environmental stresses, where the signals from the site of stimulus perception are transmitted to distal organs to elicit plant-wide responses. A wide range of signaling molecules are trafficked through the plant, but a trio of potentially interacting messengers, reactive oxygen species (ROS), Ca 2+ and electrical signaling ('trio signaling') appear to form a network supporting rapid signal transmission. The molecular components underlying this rapid communication are beginning to be identified, such as the ROS producing NAPDH oxidase RBOHD, the ion channel two pore channel 1 (TPC1), and glutamate receptor-like channels GLR3.3 and GLR3.6. The plant cell wall presents a plant-specific route for possible propagation of signals from cell to cell. However, the degree to which the cell wall limits information exchange between cells via transfer of small molecules through an extracellular route, or whether it provides an environment to facilitate transmission of regulators such as ROS or H + remains to be determined. Similarly, the role of plasmodesmata as both conduits and gatekeepers for the propagation of rapid cell-to-cell signaling remains a key open question. Regardless of how signals move from cell to cell, they help prepare distant parts of the plant for impending challenges from specific biotic or abiotic stresses. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  3. Fas Versatile Signaling and Beyond: Pivotal Role of Tyrosine Phosphorylation in Context-Dependent Signaling and Diseases

    PubMed Central

    Chakrabandhu, Krittalak; Hueber, Anne-Odile

    2016-01-01

    The Fas/FasL system is known, first and foremost, as a potent apoptosis activator. While its proapoptotic features have been studied extensively, evidence that the Fas/FasL system can elicit non-death signals has also accumulated. These non-death signals can promote survival, proliferation, migration, and invasion of cells. The key molecular mechanism that determines the shift from cell death to non-death signals had remained unclear until the recent identification of the tyrosine phosphorylation in the death domain of Fas as the reversible signaling switch. In this review, we present the connection between the recent findings regarding the control of Fas multi-signals and the context-dependent signaling choices. This information can help explain variable roles of Fas signaling pathway in different pathologies. PMID:27799932

  4. Aircrew Automated Escape Systems (AAES), In-Service Usage Data Analysis Program,

    DTIC Science & Technology

    1982-02-01

    Factors where the dotted arrows indicate correlation and the solid arrow indicates causation. A classic example is teachers salaries and beer sales (in...dollars) observed over a ten year period. TEACHERS ’ SALARY (IN $) BEER SALES (IN $) A Classical Example of Spurioazs Association Between Teachers ...8217 Salary and Beer Sales Beer sales is highly correlated with teachers salaries, but would anyone suggest that the correspond- ing increase in beer sales

  5. Case Study Application of the Biodiversity Security Index to Ranking Feasibility Studies for Ecosystem Restoration Projects of the U.S. Army Corps of Engineers

    DTIC Science & Technology

    2016-04-01

    determinations are more common for certain invertebrates , such as gastropods (snails), but the taxonomy is improving rapidly. The RSI approach to resource...arrow for invertebrate animals. Check the box for Mollusca. Then check to make sure your status and location criteria remain the same, search for the...mollusk list and store. Go back to invertebrate animals and select the down arrow for “Crustacea”. Then select crayfish, isopods, amphipods, and

  6. Study of the Feasibility of Using an Advanced Opto-Electronic Imaging Technique for Sampling Mid-Water Nekton.

    DTIC Science & Technology

    1978-11-30

    migration(diurnal) of Mycophidae and siphonophores of the suborder Physonectae. —2— _______ - ~~~~~~~~~~ _____________________________ I-~ The former...ORGANISMS PLANKTON COPEPODS TRANSLUCENT ! ARROW WORMS TRANSPARENT SIPHONOPHORES MEDUSAE AGLISCRA IGNEA FLAMING RED NEMERTEAN WORMS REDDISH ARROW WORMS...383-385 ( 1969) 9. BARHAN, Eric G., Siphonophores and the Deep Scattering Layer, Science, 140, 826—828 (1963) 10. BARHA~M , Eric C., Deep Scattering

  7. Astrocyte Sodium Signalling and Panglial Spread of Sodium Signals in Brain White Matter.

    PubMed

    Moshrefi-Ravasdjani, Behrouz; Hammel, Evelyn L; Kafitz, Karl W; Rose, Christine R

    2017-09-01

    In brain grey matter, excitatory synaptic transmission activates glutamate uptake into astrocytes, inducing sodium signals which propagate into neighboring astrocytes through gap junctions. These sodium signals have been suggested to serve an important role in neuro-metabolic coupling. So far, it is unknown if astrocytes in white matter-that is in brain regions devoid of synapses-are also able to undergo such intra- and intercellular sodium signalling. In the present study, we have addressed this question by performing quantitative sodium imaging in acute tissue slices of mouse corpus callosum. Focal application of glutamate induced sodium transients in SR101-positive astrocytes. These were largely unaltered in the presence of ionotropic glutamate receptors blockers, but strongly dampened upon pharmacological inhibition of glutamate uptake. Sodium signals induced in individual astrocytes readily spread into neighboring SR101-positive cells with peak amplitudes decaying monoexponentially with distance from the stimulated cell. In addition, spread of sodium was largely unaltered during pharmacological inhibition of purinergic and glutamate receptors, indicating gap junction-mediated, passive diffusion of sodium between astrocytes. Using cell-type-specific, transgenic reporter mice, we found that sodium signals also propagated, albeit less effectively, from astrocytes to neighboring oligodendrocytes and NG2 cells. Again, panglial spread was unaltered with purinergic and glutamate receptors blocked. Taken together, our results demonstrate that activation of sodium-dependent glutamate transporters induces sodium signals in white matter astrocytes, which spread within the astrocyte syncytium. In addition, we found a panglial passage of sodium signals from astrocytes to NG2 cells and oligodendrocytes, indicating functional coupling between these macroglial cells in white matter.

  8. Signaling equilibria in sensorimotor interactions.

    PubMed

    Leibfried, Felix; Grau-Moya, Jordi; Braun, Daniel A

    2015-08-01

    Although complex forms of communication like human language are often assumed to have evolved out of more simple forms of sensorimotor signaling, less attention has been devoted to investigate the latter. Here, we study communicative sensorimotor behavior of humans in a two-person joint motor task where each player controls one dimension of a planar motion. We designed this joint task as a game where one player (the sender) possesses private information about a hidden target the other player (the receiver) wants to know about, and where the sender's actions are costly signals that influence the receiver's control strategy. We developed a game-theoretic model within the framework of signaling games to investigate whether subjects' behavior could be adequately described by the corresponding equilibrium solutions. The model predicts both separating and pooling equilibria, in which signaling does and does not occur respectively. We observed both kinds of equilibria in subjects and found that, in line with model predictions, the propensity of signaling decreased with increasing signaling costs and decreasing uncertainty on the part of the receiver. Our study demonstrates that signaling games, which have previously been applied to economic decision-making and animal communication, provide a framework for human signaling behavior arising during sensorimotor interactions in continuous and dynamic environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Redox signaling in plants.

    PubMed

    Foyer, Christine H; Noctor, Graham

    2013-06-01

    Our aim is to deliver an authoritative and challenging perspective of current concepts in plant redox signaling, focusing particularly on the complex interface between the redox and hormone-signaling pathways that allow precise control of plant growth and defense in response to metabolic triggers and environmental constraints and cues. Plants produce significant amounts of singlet oxygen and other reactive oxygen species (ROS) as a result of photosynthetic electron transport and metabolism. Such pathways contribute to the compartment-specific redox-regulated signaling systems in plant cells that convey information to the nucleus to regulate gene expression. Like the chloroplasts and mitochondria, the apoplast-cell wall compartment makes a significant contribution to the redox signaling network, but unlike these organelles, the apoplast has a low antioxidant-buffering capacity. The respective roles of ROS, low-molecular antioxidants, redox-active proteins, and antioxidant enzymes are considered in relation to the functions of plant hormones such as salicylic acid, jasmonic acid, and auxin, in the composite control of plant growth and defense. Regulation of redox gradients between key compartments in plant cells such as those across the plasma membrane facilitates flexible and multiple faceted opportunities for redox signaling that spans the intracellular and extracellular environments. In conclusion, plants are recognized as masters of the art of redox regulation that use oxidants and antioxidants as flexible integrators of signals from metabolism and the environment.

  10. A Strategy for Minimizing Background Signal in Autoinductive Signal Amplification Reactions for Point-of-Need Assays.

    PubMed

    Brooks, Adam D; Yeung, Kimy; Lewis, Gregory G; Phillips, Scott T

    2015-09-07

    Rapid point-of-need assays are used to detect abundant biomarkers. The development of in situ signal amplification reactions could extend these assays to screening and triaging of patients for trace levels of biomarkers, even in resource-limited settings. We, and others, have developed small molecule-based in situ signal amplification reactions that eventually may be useful in this context. Herein we describe a design strategy for minimizing background signal that may occur in the absence of the target analyte, thus moving this in situ signal amplification approach one step closer to practical applications. Specifically, we describe allylic ethers as privileged connectors for linking detection and propagating functionality in a small molecule signal amplification reagent. Allylic ethers minimize background reactions while still enabling controlled release of a propagating signal in order to continue the signal amplification reaction. This paper characterizes the ability of allylic ethers to provide an amplified response, and offers insight into additional design considerations that are needed before in situ small molecule-based signal amplification becomes a viable strategy for point-of-need diagnostics.

  11. A Strategy for Minimizing Background Signal in Autoinductive Signal Amplification Reactions for Point-of-Need Assays

    PubMed Central

    Brooks, Adam D.; Yeung, Kimy; Lewis, Gregory G.

    2015-01-01

    Rapid point-of-need assays are used to detect abundant biomarkers. The development of in situ signal amplification reactions could extend these assays to screening and triaging of patients for trace levels of biomarkers, even in resource-limited settings. We, and others, have developed small molecule-based in situ signal amplification reactions that eventually may be useful in this context. Herein we describe a design strategy for minimizing background signal that may occur in the absence of the target analyte, thus moving this in situ signal amplification approach one step closer to practical applications. Specifically, we describe allylic ethers as privileged connectors for linking detection and propagating functionality in a small molecule signal amplification reagent. Allylic ethers minimize background reactions while still enabling controlled release of a propagating signal in order to continue the signal amplification reaction. This paper characterizes the ability of allylic ethers to provide an amplified response, and offers insight into additional design considerations that are needed before in situ small molecule-based signal amplification becomes a viable strategy for point-of-need diagnostics. PMID:26604988

  12. Some dynamics of signaling games.

    PubMed

    Huttegger, Simon; Skyrms, Brian; Tarrès, Pierre; Wagner, Elliott

    2014-07-22

    Information transfer is a basic feature of life that includes signaling within and between organisms. Owing to its interactive nature, signaling can be investigated by using game theory. Game theoretic models of signaling have a long tradition in biology, economics, and philosophy. For a long time the analyses of these games has mostly relied on using static equilibrium concepts such as Pareto optimal Nash equilibria or evolutionarily stable strategies. More recently signaling games of various types have been investigated with the help of game dynamics, which includes dynamical models of evolution and individual learning. A dynamical analysis leads to more nuanced conclusions as to the outcomes of signaling interactions. Here we explore different kinds of signaling games that range from interactions without conflicts of interest between the players to interactions where their interests are seriously misaligned. We consider these games within the context of evolutionary dynamics (both infinite and finite population models) and learning dynamics (reinforcement learning). Some results are specific features of a particular dynamical model, whereas others turn out to be quite robust across different models. This suggests that there are certain qualitative aspects that are common to many real-world signaling interactions.

  13. Some dynamics of signaling games

    PubMed Central

    Huttegger, Simon; Skyrms, Brian; Tarrès, Pierre; Wagner, Elliott

    2014-01-01

    Information transfer is a basic feature of life that includes signaling within and between organisms. Owing to its interactive nature, signaling can be investigated by using game theory. Game theoretic models of signaling have a long tradition in biology, economics, and philosophy. For a long time the analyses of these games has mostly relied on using static equilibrium concepts such as Pareto optimal Nash equilibria or evolutionarily stable strategies. More recently signaling games of various types have been investigated with the help of game dynamics, which includes dynamical models of evolution and individual learning. A dynamical analysis leads to more nuanced conclusions as to the outcomes of signaling interactions. Here we explore different kinds of signaling games that range from interactions without conflicts of interest between the players to interactions where their interests are seriously misaligned. We consider these games within the context of evolutionary dynamics (both infinite and finite population models) and learning dynamics (reinforcement learning). Some results are specific features of a particular dynamical model, whereas others turn out to be quite robust across different models. This suggests that there are certain qualitative aspects that are common to many real-world signaling interactions. PMID:25024209

  14. Signal reception and transmission.

    PubMed

    Gough, Nancy R

    2006-12-05

    From plants to yeast to animals, new pathways and updates to the Database of Cell Signaling highlight how signals received at the surface are transmitted into the cell to mediate complex cellular responses.

  15. Digital Signal Processing Based Biotelemetry Receivers

    NASA Technical Reports Server (NTRS)

    Singh, Avtar; Hines, John; Somps, Chris

    1997-01-01

    This is an attempt to develop a biotelemetry receiver using digital signal processing technology and techniques. The receiver developed in this work is based on recovering signals that have been encoded using either Pulse Position Modulation (PPM) or Pulse Code Modulation (PCM) technique. A prototype has been developed using state-of-the-art digital signal processing technology. A Printed Circuit Board (PCB) is being developed based on the technique and technology described here. This board is intended to be used in the UCSF Fetal Monitoring system developed at NASA. The board is capable of handling a variety of PPM and PCM signals encoding signals such as ECG, temperature, and pressure. A signal processing program has also been developed to analyze the received ECG signal to determine heart rate. This system provides a base for using digital signal processing in biotelemetry receivers and other similar applications.

  16. Steganography in arrhythmic electrocardiogram signal.

    PubMed

    Edward Jero, S; Ramu, Palaniappan; Ramakrishnan, S

    2015-08-01

    Security and privacy of patient data is a vital requirement during exchange/storage of medical information over communication network. Steganography method hides patient data into a cover signal to prevent unauthenticated accesses during data transfer. This study evaluates the performance of ECG steganography to ensure secured transmission of patient data where an abnormal ECG signal is used as cover signal. The novelty of this work is to hide patient data into two dimensional matrix of an abnormal ECG signal using Discrete Wavelet Transform and Singular Value Decomposition based steganography method. A 2D ECG is constructed according to Tompkins QRS detection algorithm. The missed R peaks are computed using RR interval during 2D conversion. The abnormal ECG signals are obtained from the MIT-BIH arrhythmia database. Metrics such as Peak Signal to Noise Ratio, Percentage Residual Difference, Kullback-Leibler distance and Bit Error Rate are used to evaluate the performance of the proposed approach.

  17. Multi-signal FIB/SEM tomography

    NASA Astrophysics Data System (ADS)

    Giannuzzi, Lucille A.

    2012-06-01

    Focused ion beam (FIB) milling coupled with scanning electron microscopy (SEM) on the same platform enables 3D microstructural analysis of structures using FIB for serial sectioning and SEM for imaging. Since FIB milling is a destructive technique, the acquisition of multiple signals from each slice is desirable. The feasibility of collecting both an inlens backscattered electron (BSE) signal and an inlens secondary electron (SE) simultaneously from a single scan of the electron beam from each FIB slice is demonstrated. The simultaneous acquisition of two different SE signals from two different detectors (inlens vs. Everhart-Thornley (ET) detector) is also possible. Obtaining multiple signals from each FIB slice with one scan increases the acquisition throughput. In addition, optimization of microstructural and morphological information from the target is achieved using multi-signals. Examples of multi-signal FIB/SEM tomography from a dental implant will be provided where both material contrast from the bone/ceramic coating/Ti substrate phases and porosity in the ceramic coating will be characterized.

  18. Wnt signaling activates Shh signaling in early postnatal intervertebral discs, and re-activates Shh signaling in old discs in the mouse.

    PubMed

    Winkler, Tamara; Mahoney, Eric J; Sinner, Debora; Wylie, Christopher C; Dahia, Chitra Lekha

    2014-01-01

    Intervertebral discs (IVDs) are strong fibrocartilaginous joints that connect adjacent vertebrae of the spine. As discs age they become prone to failure, with neurological consequences that are often severe. Surgical repair of discs treats the result of the disease, which affects as many as one in seven people, rather than its cause. An ideal solution would be to repair degenerating discs using the mechanisms of their normal differentiation. However, these mechanisms are poorly understood. Using the mouse as a model, we previously showed that Shh signaling produced by nucleus pulposus cells activates the expression of differentiation markers, and cell proliferation, in the postnatal IVD. In the present study, we show that canonical Wnt signaling is required for the expression of Shh signaling targets in the IVD. We also show that Shh and canonical Wnt signaling pathways are down-regulated in adult IVDs. Furthermore, this down-regulation is reversible, since re-activation of the Wnt or Shh pathways in older discs can re-activate molecular markers of the IVD that are lost with age. These data suggest that biological treatments targeting Wnt and Shh signaling pathways may be feasible as a therapeutic for degenerative disc disease.

  19. Zufällige Signale

    NASA Astrophysics Data System (ADS)

    Plaßmann, Wilfried

    Die hier betrachteten Signale werden auch als stochastische Signale bezeichnet. Sie sind zufällig, d. h. ihr Augenblickswert ist nicht vorhersagbar. Abb. 118.1 zeigt eine Unterteilung nach den Signaleigenschaften. Über die nichtstationären Signale lässt sich keinerlei Aussage machen, und sie werden hier deshalb auch nicht weiter betrachtet. Für die stationären Signale gilt, dass ihr Momentanwert zwar auch nicht vorhergesagt werden kann, dass sie aber trotzdem gewisse auswertbare Eigenschaften besitzen, die allerdings statistischer Art sind und deshalb nur mit den Gesetzen der Wahrscheinlichkeitstheorie erfasst werden können. Zwar sind - theoretisch - für die Anwendung der Wahrscheinlichkeitstheorie unendlich viele Probenwerte zu nehmen, in der Praxis hat sich aber gezeigt, dass man auch mit einer endlichen Anzahl dem gesuchten Wert schon ausreichend nahe kommen kann.

  20. Signalling crosstalk in plants: emerging issues.

    PubMed

    Taylor, Jane E; McAinsh, Martin R

    2004-01-01

    The Oxford English Dictionary defines crosstalk as 'unwanted transfer of signals between communication channels'. How does this definition relate to the way in which we view the organization and function of signalling pathways? Recent advances in the field of plant signalling have challenged the traditional view of a signalling transduction cascade as isolated linear pathways. Instead the picture emerging of the mechanisms by which plants transduce environmental signals is of the interaction between transduction chains. The manner in which these interactions occur (and indeed whether the transfer of these signals is 'unwanted' or beneficial) is currently the topic of intense research.