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1

Tests of the Weak Equivalence Principle with Trapped Antimatter  

Microsoft Academic Search

Recent developments in the trapping of ions and neutral atoms suggest that significant improvements in the precision of spectroscopic measurements on such systems can be expected. The application of these techniques to trapped antiprotons, positrons and antihydrogen atoms opens up new possibilities for precision tests of the weak equivalence principle (WEP) for antimatter. It is shown that constraints on WEP

Richard J. Hughes; Michael H. Holzscheiter

1992-01-01

2

Economic decision-making compared with an equivalent motor task.  

PubMed

There is considerable evidence that human economic decision-making deviates from the predictions of expected utility theory (EUT) and that human performance conforms to EUT in many perceptual and motor decision tasks. It is possible that these results reflect a real difference in decision-making in the 2 domains but it is also possible that the observed discrepancy simply reflects typical differences in experimental design. We developed a motor task that is mathematically equivalent to choosing between lotteries and used it to compare how the same subject chose between classical economic lotteries and the same lotteries presented in equivalent motor form. In experiment 1, we found that subjects are more risk seeking in deciding between motor lotteries. In experiment 2, we used cumulative prospect theory to model choice and separately estimated the probability weighting functions and the value functions for each subject carrying out each task. We found no patterned differences in how subjects represented outcome value in the motor and the classical tasks. However, the probability weighting functions for motor and classical tasks were markedly and significantly different. Those for the classical task showed a typical tendency to overweight small probabilities and underweight large probabilities, and those for the motor task showed the opposite pattern of probability distortion. This outcome also accounts for the increased risk-seeking observed in the motor tasks of experiment 1. We conclude that the same subject distorts probability, but not value, differently in making identical decisions in motor and classical form. PMID:19332799

Wu, Shih-Wei; Delgado, Mauricio R; Maloney, Laurence T

2009-03-30

3

Economic decision-making compared with an equivalent motor task  

PubMed Central

There is considerable evidence that human economic decision-making deviates from the predictions of expected utility theory (EUT) and that human performance conforms to EUT in many perceptual and motor decision tasks. It is possible that these results reflect a real difference in decision-making in the 2 domains but it is also possible that the observed discrepancy simply reflects typical differences in experimental design. We developed a motor task that is mathematically equivalent to choosing between lotteries and used it to compare how the same subject chose between classical economic lotteries and the same lotteries presented in equivalent motor form. In experiment 1, we found that subjects are more risk seeking in deciding between motor lotteries. In experiment 2, we used cumulative prospect theory to model choice and separately estimated the probability weighting functions and the value functions for each subject carrying out each task. We found no patterned differences in how subjects represented outcome value in the motor and the classical tasks. However, the probability weighting functions for motor and classical tasks were markedly and significantly different. Those for the classical task showed a typical tendency to overweight small probabilities and underweight large probabilities, and those for the motor task showed the opposite pattern of probability distortion. This outcome also accounts for the increased risk-seeking observed in the motor tasks of experiment 1. We conclude that the same subject distorts probability, but not value, differently in making identical decisions in motor and classical form.

Wu, Shih-Wei; Delgado, Mauricio R.; Maloney, Laurence T.

2009-01-01

4

Hierarchical IRT Examination of Isomorphic Equivalence of Complex Constructed Response Tasks.  

ERIC Educational Resources Information Center

|This paper explores the application of a technique for hierarchical item response theory (IRT) calibration of complex constructed response tasks that has promise both as a calibration tool and as a means of evaluating the isomorphic equivalence of complex constructed response tasks. Isomorphic tasks are explicitly and rigorously designed to be…

Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.

5

Classification of motor imagery tasks for brain-computer interface applications by means of two equivalent dipoles analysis  

Microsoft Academic Search

We have developed a novel approach using source analysis for classifying motor imagery tasks. Two-equivalent-dipoles analysis was proposed to aid classification of motor imagery tasks for brain-computer interface (BCI) applications. By solving the electroencephalography (EEG) inverse problem of single trial data, it is found that the source analysis approach can aid classification of motor imagination of left- or right-hand movement

Baharan Kamousi; Zhongming Liu; Bin He

2005-01-01

6

Is there a cost price for the heat produced from electro-nuclear power stations. Is thermodynamic equivalence an economic trap  

Microsoft Academic Search

The thermodynamic equivalence between heat and electricity, when used uncritically and carelessly translated into a price equivalence, can effectively hide a very formidable economic 'trap' and the advantage it appears to indicate for heat production at relatively low temperatures is to be distrusted; in many cases, this advantage may be of little importance in comparison with the disadvantages of low

Charroppin

1977-01-01

7

Comparison of Distortion of Probability information in Decision under Risk and an equivalent Visual Task  

PubMed Central

Decision makers typically overweight small probabilities and underweight large. However, there are recent reports that, when probability is presented in relative frequency form, this typical pattern reverses. We tested this hypothesis, comparing decision making in two decision tasks, in which probability was either stated numerically or conveyed through a visual representation. In the visual task, participants chose between firing a ‘stochastic bullet’ at a large target for a small reward or at a small target for a large reward. Participants’ knowledge of probability in the visual task was the results of extensive practice firing bullets at targets. In the classical numerical task, they chose between pairs of lotteries with probabilities and rewards matched to those in the visual task. We found that participants had significantly different probability weight functions in the two tasks but the pattern for the visual task was the typical, not the reversed, pattern.

Glaser, Craig; Maloney, Laurence T.; Trommershauser, Julia; Mamassian, Pascal

2013-01-01

8

Comparison of the distortion of probability information in decision under risk and an equivalent visual task.  

PubMed

Decision makers typically overweight small probabilities and underweight large probabilities. However, there are recent reports that when probability is presented in the form of relative frequencies, this typical pattern reverses. We tested this hypothesis by comparing decision making in two tasks: In one task, probability was stated numerically, and in the other task, it was conveyed through a visual representation. In the visual task, participants chose whether a "stochastic bullet" should be fired at either a large target for a small reward or a small target for a large reward. Participants' knowledge of probability in the visual task was the result of extensive practice firing bullets at targets. In the classical numerical task, participants chose between pairs of lotteries with probabilities and rewards matched to the probabilities and rewards in the visual task. We found that participants' probability-weighting functions were significantly different in the two tasks, but the pattern for the visual task was the typical, not the reversed, pattern. PMID:22395127

Glaser, Craig; Trommershäuser, Julia; Mamassian, Pascal; Maloney, Laurence T

2012-03-06

9

New head equivalent phantom for task and image performance evaluation representative for neurovascular procedures occurring in the Circle of Willis  

NASA Astrophysics Data System (ADS)

Phantom equivalents of different human anatomical parts are routinely used for imaging system evaluation or dose calculations. The various recommendations on the generic phantom structure given by organizations such as the AAPM, are not always accurate when evaluating a very specific task. When we compared the AAPM head phantom containing 3 mm of aluminum to actual neuro-endovascular image guided interventions (neuro-EIGI) occurring in the Circle of Willis, we found that the system automatic exposure rate control (AERC) significantly underestimated the x-ray parameter selection. To build a more accurate phantom for neuro-EIGI, we reevaluated the amount of aluminum which must be included in the phantom. Human skulls were imaged at different angles, using various angiographic exposures, at kV's relevant to neuro-angiography. An aluminum step wedge was also imaged under identical conditions, and a correlation between the gray values of the imaged skulls and those of the aluminum step thicknesses was established. The average equivalent aluminum thickness for the skull samples for frontal projections in the Circle of Willis region was found to be about 13 mm. The results showed no significant changes in the average equivalent aluminum thickness with kV or mAs variation. When a uniform phantom using 13 mm aluminum and 15 cm acrylic was compared with an anthropomorphic head phantom the x-ray parameters selected by the AERC system were practically identical. These new findings indicate that for this specific task, the amount of aluminum included in the head equivalent must be increased substantially from 3 mm to a value of 13 mm.

Ionita, Ciprian N.; Loughran, Brendan; Jain, Amit; Swetadri Vasan, S. N.; Bednarek, Daniel R.; Levy, Elad; Siddiqui, Adnan H.; Snyder, Kenneth V.; Hopkins, L. N.; Rudin, Stephen

2012-02-01

10

New head equivalent phantom for task and image performance evaluation representative for neurovascular procedures occurring in the Circle of Willis  

PubMed Central

Phantom equivalents of different human anatomical parts are routinely used for imaging system evaluation or dose calculations. The various recommendations on the generic phantom structure given by organizations such as the AAPM, are not always accurate when evaluating a very specific task. When we compared the AAPM head phantom containing 3 mm of aluminum to actual neuro-endovascular image guided interventions (neuro-EIGI) occurring in the Circle of Willis, we found that the system automatic exposure rate control (AERC) significantly underestimated the x-ray parameter selection. To build a more accurate phantom for neuro-EIGI, we reevaluated the amount of aluminum which must be included in the phantom. Human skulls were imaged at different angles, using various angiographic exposures, at kV’s relevant to neuro-angiography. An aluminum step wedge was also imaged under identical conditions, and a correlation between the gray values of the imaged skulls and those of the aluminum step thicknesses was established. The average equivalent aluminum thickness for the skull samples for frontal projections in the Circle of Willis region was found to be about 13 mm. The results showed no significant changes in the average equivalent aluminum thickness with kV or mAs variation. When a uniform phantom using 13 mm aluminum and 15 cm acrylic was compared with an anthropomorphic head phantom the x-ray parameters selected by the AERC system were practically identical. These new findings indicate that for this specific task, the amount of aluminum included in the head equivalent must be increased substantially from 3 mm to a value of 13 mm.

Ionita, Ciprian N.; Loughran, Brendan; Jain, Amit; Swetadri Vasan, S. N.; Bednarek, Daniel R.; Levy, Elad; Siddiqui, Adnan H.; Snyder, Kenneth V.; Hopkins, L. N.; Rudin, Stephen

2012-01-01

11

The Task and Ego Orientation in Sport Questionnaire: construct equivalence and mean differences across gender.  

PubMed

Research on achievement goal orientation in sport has relied primarily on traditional statistical methodology to examine group mean differences. Unfortunately, examination of the measurement model is generally ignored prior to means testing. This study reports an application of structural equation modeling (SEM) in testing measurement invariance and latent mean structure of the Task and Ego Orientation in Sport Questionnaire (TEOSQ; Duda & Nicholls, 1989) using male and female college students. A confirmatory factor analysis for testing invariance revealed invariant measurement properties and factor structures across gender, indicating that task and ego orientation are similarly conceptualized by male and female students. Subsequent testing of latent mean structures, however, showed significant gender differences with respect to ego orientation, but no difference in task orientation. The SEM procedures used in the present study demonstrate additional construct validity and internal consistency reliability for the TEOSQ and, by confirming its factor structure, provide a sound psychometric basis for its continued use in substantive studies focusing on the comparison of achievement goal orientation across gender. PMID:8836004

Li, F; Harmer, P; Acock, A

1996-06-01

12

The ABCs of computerized naming: equivalency, reliability, and predictive validity of a computerized rapid automatized naming (RAN) task.  

PubMed

Population-based studies indicate dual routes to disabled reading in adolescence and adulthood: slowed acquisition of single word reading and ADHD (particularly inattention) in early childhood. Impairments in rapid serial naming may be a factor common to both problems. The gold-standard measure of this ability, the Rapid Automatized Naming Task (RAN; [Denckla MB, Rudel R. Rapid automatized naming of pictured objects, colors, letters and numbers by normal children. Cortex 1974;10:186-202]), has traditionally been administered in a paper-pencil format. Recently however, researchers [Neuhaus GF, Carlson CD, Jeng WM, Post Y, Swank PR. The reliability and validity of rapid automatized scoring software ratings for the determination of pause and articulation component durations. Educ Psychol Meas 2001;61:490-504] have begun to use computerized versions of the RAN. Here a slightly modified computerized version of the RAN was created and the equivalency between the computerized RAN and the conventional version was investigated using a university student sample. Naming times on the conventional and computerized RAN were highly correlated, overall, and for each of the four RAN stimulus types (letters, digit, colors, objects). Conventional and computerized RAN times predicted reading rate and reading comprehension scores equally well and both showed very high test-retest reliability. With our university student sample, findings indicate equivalency between the two testing mediums in all areas examined. PMID:16412518

Howe, Ashley E; Arnell, Karen M; Klein, Raymond M; Joanisse, Marc F; Tannock, Rosemary

2006-01-10

13

Search, Enumeration, and Aging: Eye Movement Requirements Cause Age-Equivalent Performance in Enumeration but Not in Search Tasks  

Microsoft Academic Search

Response time (RT) and fixation frequency were measured for young and older adults in search and enumeration tasks under high- and low-attentional competition conditions. There was an age-related decrement in search rates for single targets both for RT and fixation frequency, but there was no deficit in enumeration rates either with or without distractors even though serial enumeration rates were

Derrick G. Watson; Elizabeth A. Maylor; Lucy A. M. Bruce

2005-01-01

14

The reliability and validity of a lift simulator and its functional equivalence with free weight lifting tasks  

Microsoft Academic Search

The combination of Workers' Compensation legal claims and the enactment of the Americans with Disabilities Act (1990) has created a need for more objective and realistic trunk muscle testing. The LIDOLift (Loredan, Inc.) is a computerized dynamometer which has the capabilities to test multijoint coordinated lifting tasks in isometric, isokinetic, and isoinertial modes of operation. The calibration of the electromechanical

Patrick J. Sparto; Mohamad Parnianpour; Kinda A. Khalaf; Sheldon R. Simon

1995-01-01

15

Is Talk 'Cheap'? An Initial Investigation of the Equivalence of Alcohol Purchase Task Performance for Hypothetical and Actual Rewards  

PubMed Central

Background Behavioral economic alcohol purchase tasks (APTs) are self-report measures of alcohol demand that assess estimated consumption at escalating levels of price. However, the relationship between estimated performance for hypothetical outcomes and choices for actual outcomes has not been determined. The present study examined both the correspondence between choices for hypothetical and actual outcomes, and the correspondence between estimated alcohol consumption and actual drinking behavior. A collateral goal of the study was to examine the effects of alcohol cues on APT performance. Methods Forty one heavy-drinking adults (56% male) participated in a human laboratory protocol comprising APTs for hypothetical and actual alcohol and money, an alcohol cue reactivity paradigm, an alcohol self-administration period, and a recovery period. Results Pearson correlations revealed very high correspondence between APT performance for hypothetical and actual alcohol (ps < .001). Estimated consumption on the APT was similarly strongly associated with actual consumption during the self-administration period (r = .87, p <.001). Exposure to alcohol cues significantly increased subjective craving and arousal, and had a trend-level effect on intensity of demand, in spite of notable ceiling effects. Associations among motivational indices were highly variable, suggesting multidimensionality. Conclusions These results suggest there may be close correspondence both between value preferences for hypothetical alcohol and actual alcohol, and between estimated consumption and actual consumption. Methodological considerations and priorities for future studies are discussed.

Amlung, Michael; Acker, John; Stojek, Monika; Murphy, James G.; MacKillop, James

2011-01-01

16

6.EE Equivalent Expressions  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Which of the following expressions are equivalent? Why? If an expression has no match, write 2 equivalent expressions to match it. $2(x+4)$ $8+2x$ $2x+...

17

Magnetoelectric charge trap memory.  

PubMed

It is demonstrated that a charge-trapping layer placed in proximity to a ferromagnetic metal enables efficient electrical and optical control of the metal's magnetic properties. Retention of charge trapped inside the charge-trapping layer provides nonvolatility to the magnetoelectric effect and enhances its efficiency by an order of magnitude. As such, an engineered charge-trapping layer can be used to realize the magnetoelectric equivalent to today's pervasive charge trap flash memory technology. Moreover, by supplying trapped charges optically instead of electrically, a focused laser beam can be used to imprint the magnetic state into a continuous metal film. PMID:22300444

Bauer, Uwe; Przybylski, Marek; Kirschner, Jürgen; Beach, Geoffrey S D

2012-02-08

18

7.EE Equivalent Expressions?  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: If we multiply $\\frac{x}{2} + \\frac34$ by 4, we get $2x+3$. Is $2x+3$ an equivalent expression to $\\frac{x}{2} + \\frac34$?...

19

On the Equivalence of Local-Mode Finding, Robust Estimation and Mean-Shift Analysis as Used in Early Vision Tasks  

Microsoft Academic Search

In this paper we show the equivalence of three tech- niques used in image processing: local-mode finding, robust-estimation and mean-shift analysis. The computa- tional common element in all these image operators is the spatial-tonal normalized convolution, an image operator that generalizes the bilateral filter.

Rein Van Den Boomgaard; Joost Van De Weijer

2002-01-01

20

Equivalence of kinetic theories  

NASA Astrophysics Data System (ADS)

We discuss the equivalence of two non-equilibrium kinetic theories, which describe the evolution of a dilute, Bose-Einstein condensed atomic gas in a harmonic trap. The second order JILA kinetic equations(R. Walser, J. Cooper, and M. Holland, Phys. Rev. A 63), 013607 (2001). reduce to the Gross-Pitaevskii equation and the quantum Boltzmann equation in the respective limits. They are thus capable of describing the system in equilibrium (finite temperature) as well as in non-equilibrium (real time). We have found this theory to be equivalent to the non-equilibrium Green's function approach originally proposed by Kadanoff and Baym and more recently applied to inhomogeneous trapped systems by M. Imamovi?-Tomasovi? and A. Griffin(M. Imamovi?)-Tomasovi? and A. Griffin, in Progress in Nonequilibrium Green's Functions, edited by M. Bonitz (World Scientific, Singapore, 2000), p. 404, arXiv:cond-mat/9911402..

Wachter, J.; Walser, R.; Cooper, J.; Holland, M.

2001-05-01

21

Equivalent Fractions!  

NSDL National Science Digital Library

How good at determining equivalent fractions are you? Test your skills with these various fraction games to find out! You have recently been learning about fractions and their equivalency. Try this game to test your knowledge of Equivalent Fractions!! Be sure to notice the "hints" under some of the questions to help you get the correct answer. Good Luck! Continue to master your skills by playing the Dirt Bike Proportions! game. How quickly you ...

Pearce, Ms.

2011-11-06

22

Equivalent Fractions  

NSDL National Science Digital Library

What is an equivalent fraction? Students, I want you to create song about fractions. Here is a fraction song video to help you get and idea. Remember your song should be at least five sentences long. Math Song- Equivalent Fractions Students, I want you to click on the website below and the play the fraction game. Let's see how many ...

Ogle, Miss

2012-04-05

23

Evaluating steam trap performance  

Microsoft Academic Search

This paper presents a method for evaluating the performance level of steam traps by preparing an economic analysis of several types to determine the equivalent uniform annual cost. A series of tests on steam traps supplied by six manufacturers provided data for determining the relative efficiencies of each unit. The comparison was made using a program developed for the Texas

Fuller

1985-01-01

24

Evaluating steam trap performance  

SciTech Connect

This paper presents a method for evaluating the performance level of steam traps by preparing an economic analysis of several types to determine the equivalent uniform annual cost. A series of tests on steam traps supplied by six manufacturers provided data for determining the relative efficiencies of each unit. The comparison was made using a program developed for the Texas Instruments T1-59 programmable calculator to evaluate overall steam trap economics.

Fuller, N.Y.

1985-08-08

25

Equivalent Fractions  

NSDL National Science Digital Library

Teachers can use this interactive tool to help students build conceptual understanding of equivalent fractions by emphasizing how visual models represent equivalence. Students learn the value of multiplying a fraction with a value of one. This page includes a video demonstration of the tool and sample lessons from the Conceptua curriculum. Free registration is required to use the tool. A paid subscription is necessary to access full curriculum and allow full student use.

2011-01-01

26

Numerical Equivalence and the Developmentally Impaired.  

ERIC Educational Resources Information Center

|This research was designed to document the ability of Down's Syndrome children aged 5-10 to perform equivalence tasks, and to investigate possible relationships between such performance and the presence of certain potentially confounding task variables. (MNS)|

Yarmish, Rina

1988-01-01

27

Reasons for the Decalage between Identity Conservation and Equivalence Conservation.  

ERIC Educational Resources Information Center

|Two experiments investigated which of two factors is responsible for decalage between Piaget's equivalence and identity conservation tasks. Performance of 78 primary school students between 57 and 79 months of age was compared on equivalence and identity tasks and a third task, equivalence I, which retains transitivity requirement of Piaget's…

Gold, Ron

1983-01-01

28

Equivalence-Equivalence: Matching Stimuli with Same Discriminative Functions  

ERIC Educational Resources Information Center

|Previous studies have shown that after being trained on A-B and A-C match-to-sample tasks, adults match not only same-class B and C stimuli (equivalence) but also BC compounds with same-class elements and with different-class elements (BC-BC). The assumption was that the BC-BC performances are based on matching equivalence and nonequivalence…

Carpentier, Franck; Smeets, Paul M.; Barnes-Holmes, Dermot

2004-01-01

29

Matching Derived Functionally-Same Stimulus Relations: Equivalence-Equivalence and Classical Analogies  

ERIC Educational Resources Information Center

Previous studies have shown that, after being trained on A-B and A-C matching tasks, subjects match not only functionally-same B and C stimuli (stimulus equivalence), but also BC compounds with same-class elements and BC compounds with different-class elements (equivalence-equivalence). Similar performances are required in classical analogies (a :…

Carpentier, Franck; Smeets, Paul M.; Barnes-Holmes, Dermot; Stewart, Ian

2004-01-01

30

Magnetic Trapping - Trapped Radiation  

NSDL National Science Digital Library

This set of five web pages provides a non-mathematical introduction to the motion of charged particles in magnetic fields. These pages describe the "guiding center motion" which determines the motion of ions and electrons trapped in the Earth's magnetic field and in laboratory plasma devices. Also covered are gyration and mirroring, adiabatic invariance and drifts due to an electric field and gradients in the magnetic field intensity. This is part of the work "The Exploration of the Earth's Magnetosphere". A Spanish translation is available.

Stern, David

2005-04-27

31

Institutional Trap  

Microsoft Academic Search

One of the main obstacles for successful economic development is the formation of institutional traps, inefficient yet stable norms of behaviour. Domination of barter exchange, arrears, corruption and black market activities are examples of institutional traps that have hampered reforms in transition economies. Institutional traps are supported by mechanisms of coordination, learning, linkage and cultural inertia. The acceleration of economic

Victor Polterovich

2007-01-01

32

Equivalent Curves in Surfaces  

Microsoft Academic Search

We consider various notions of equivalence for homotopy classes of curves on hyperbolic surfaces based on topological, algebraic, and geometric structures, and find the relationships between these equivalences.

Christopher J. Leininger

2003-01-01

33

COLD TRAPS  

DOEpatents

A cold trap is presented for removing a condensable component from a gas mixture by cooling. It consists of a shell, the exterior surface of which is chilled by a refrigerant, and conductive fins welded inside the shell to condense the gas, and distribute the condensate evenly throughout the length of the trap, so that the trap may function until it becomes completely filled with the condensed solid. The contents may then be removed as either a gas or as a liquid by heating the trap. This device has particuinr use as a means for removing uranium hexafluoride from the gaseous diffusion separation process during equipment breakdown and repair periods.

Thompson, W.I.

1958-09-30

34

Optical trapping  

PubMed Central

Since their invention just over 20 years ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology and physics. Capabilities have evolved from simple manipulation to the application of calibrated forces on—and the measurement of nanometer-level displacements of—optically trapped objects. We review progress in the development of optical trapping apparatus, including instrument design considerations, position detection schemes and calibration techniques, with an emphasis on recent advances. We conclude with a brief summary of innovative optical trapping configurations and applications.

Neuman, Keir C.; Block, Steven M.

2006-01-01

35

Optical trapping  

SciTech Connect

Since their invention just over 20 years ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology and physics. Capabilities have evolved from simple manipulation to the application of calibrated forces on - and the measurement of nanometer-level displacements of - optically trapped objects. We review progress in the development of optical trapping apparatus, including instrument design considerations, position detection schemes and calibration techniques, with an emphasis on recent advances. We conclude with a brief summary of innovative optical trapping configurations and applications.

Neuman, Keir C.; Block, Steven M. [Department of Biological Sciences, and Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)

2004-09-01

36

EFFECT OF FILTER TEMPERATURE ON TRAPPING ZINC VAPOR  

Microsoft Academic Search

To address the Zn contamination issue in the TEF, a multi-task experimental program was initiated. The first experimental task was completed and is reported in Ref. 1. The results of the second experimental task are reported here. This task examined the effect of filter temperature on trapping efficiency and deposit morphology. Based on the first experimental tasks that examined filter

Korinko

2011-01-01

37

PATHOGEN EQUIVALENCY COMMITTEE UPDATE: PFRP EQUIVALENCY DETERMINATIONS  

EPA Science Inventory

This presentation will: Review the mandate of the Pathogen Equivalency Committee Review the PEC's current membership of 10 Discuss how a typical application is evaluated Note where information can be found List present deliberations/applications and describe t...

38

4.NF Fraction Equivalence  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Explain why $\\frac{6}{10} = \\frac{60}{100}$. Draw a picture to illustrate your explanation....

39

Steam trap  

SciTech Connect

A steam trap is described for expelling large quantities of condensate held at low pressure and for self locking at pressures above a predetermined pressure. The process comprises: a body including an input port, and an output port; a chamber within the body communicating with the output port. The chamber has sidewalls and an annular shoulder adjacent the sidewalls; the input port including an extension extending into the chamber and having an end surface forming a seating surface within the chamber; and closure means for automatically opening and closing the steam trap. The closure means are disposed within the chamber in substantially sealing engagement with the chamber sidewalls.

Kline, L.B.

1987-05-12

40

Equivalent Fraction Finder  

NSDL National Science Digital Library

This interactive Java applet helps users explore equivalent fractions through partitioning circles and squares. The applet provides a random fraction and the user creates one or two equivalent representations of that fraction by partitioning and coloring a square (or circle). The applet also plots the fraction on a number line and points from the shape to the number line displaying its equivalent value after the fraction is built. Options include choice of circles or squares, one or two equivalent fractions, and a scoring feature allows users to keep track of the number correct.

2006-01-01

41

Equivalent Fraction Pointer  

NSDL National Science Digital Library

This interactive Java applet helps users explore equivalent fractions through partitioning circles and squares. The applet provides a random fraction and the user creates one or two equivalent representations of that fraction by partitioning and coloring a square (or circle). The applet also plots the fraction on a number line and points from the shape to the number line displaying its equivalent value while the fraction is being built. Options include choice of circles or squares, one or two equivalent fractions, and a scoring feature allows users to keep track of the number correct.

2006-01-01

42

INSECT TRAP  

Technology Transfer Automated Retrieval System (TEKTRAN)

FLYBRELLA describes a lightweight inexpensive trap that can be hung like an upside-down umbrella in prominent locations where the house flies rest. It consists of a perforated transparent tube that house flies were found to enter readily, containing a strip of rapid-acting sugar-based toxicant. An i...

43

Steam trap  

Microsoft Academic Search

A steam trap is described for expelling large quantities of condensate held at low pressure and for self locking at pressures above a predetermined pressure. The process comprises: a body including an input port, and an output port; a chamber within the body communicating with the output port. The chamber has sidewalls and an annular shoulder adjacent the sidewalls; the

Kline

1987-01-01

44

Equivalence hypothesis testing  

Microsoft Academic Search

In statistical applications, such as a comparison of two items, it is useful to know whether one item is equivalent to another. Similarly it is often desirable to know whether one item can act as a substitute for another. Applications of the concept of equivalence include blend and flavor modifications of products, substitution of generic drugs for brand-name drugs, modifications

Daniel M. Ennis; John M. Ennis

2010-01-01

45

Geodesic equivalence and integrability  

Microsoft Academic Search

We suggest a construction that, given a trajectorial diffeomorphism between\\u000atwo Hamiltonian systems, produces integrals of them.\\u000a As the main example we treat geodesic equivalence of metrics.\\u000a We show that the existence of a non-trivially geodesically equivalent metric\\u000aleads to Liouville integrability, and present explicit formulae for integrals.

Petar J. Topalov; Vladimir S. Matveev

1999-01-01

46

Involute, minimal, outer, and increasingly trapped spheres  

SciTech Connect

Seven different refinements of trapped surfaces are proposed, each intended as potential stability conditions. This article concerns spherical symmetry, but each condition can be generalized. Involute trapped spheres satisfy a similar condition to minimal trapped spheres, which are strictly minimal with respect to the Kodama vector. There is also a weaker version of involute trapped spheres. Outer trapped spheres have positive surface gravity. Increasingly (future, respectively, past) trapped spheres generate spheres which are more trapped in a (future, respectively, past) causal direction, with three types: in any such causal direction, along the dual Kodama vector, and in some such causal direction. Assuming the null energy condition, the seven conditions form a strict hierarchy, in the above order. In static space-times, they reduce to three inequivalent definitions, namely, minimal, outer, and increasingly trapped spheres. For a widely considered class of so-called nice (or nondirty) black holes, minimal trapped and outer trapped become equivalent. Reissner-Nordstroem black holes provide examples of this, and that the increasingly trapped differs. Examples where all three refinements differ are provided by a simple family of dirty black holes parametrized by mass and singularity area.

Hayward, Sean A. [Center for Astrophysics, Shanghai Normal University, 100 Guilin Road, Shanghai 200234 (China)

2010-01-15

47

MultiTask Feature Learning  

Microsoft Academic Search

We present a method for learning a low-dimensional representation which is shared across a set of multiple related tasks. The method builds upon the well- known 1-norm regularization problem using a new regularizer which controls the number of learned features common for all the tasks. We show that this problem is equivalent to a convex optimization problem and develop an

Andreas Argyriou; Theodoros Evgeniou; Massimiliano Pontil

2006-01-01

48

Equivalent Fraction Activities  

NSDL National Science Digital Library

This web page contains four Flash applets that help students develop fraction concepts. In the three demonstrations, users can adjust the numerators and denominators of two fractions to compare them or to create two equivalent fractions, represented visually by either fraction bars or circles or by both. A game applet challenges the student to create a fraction equivalent to a given fraction and provides a check. The applets lend themselves well to classroom discussions with interactive white boards.

Weddell, Mark

2003-01-01

49

Trapped antihydrogen.  

PubMed

Antimatter was first predicted in 1931, by Dirac. Work with high-energy antiparticles is now commonplace, and anti-electrons are used regularly in the medical technique of positron emission tomography scanning. Antihydrogen, the bound state of an antiproton and a positron, has been produced at low energies at CERN (the European Organization for Nuclear Research) since 2002. Antihydrogen is of interest for use in a precision test of nature's fundamental symmetries. The charge conjugation/parity/time reversal (CPT) theorem, a crucial part of the foundation of the standard model of elementary particles and interactions, demands that hydrogen and antihydrogen have the same spectrum. Given the current experimental precision of measurements on the hydrogen atom (about two parts in 10(14) for the frequency of the 1s-to-2s transition), subjecting antihydrogen to rigorous spectroscopic examination would constitute a compelling, model-independent test of CPT. Antihydrogen could also be used to study the gravitational behaviour of antimatter. However, so far experiments have produced antihydrogen that is not confined, precluding detailed study of its structure. Here we demonstrate trapping of antihydrogen atoms. From the interaction of about 10(7) antiprotons and 7?×?10(8) positrons, we observed 38 annihilation events consistent with the controlled release of trapped antihydrogen from our magnetic trap; the measured background is 1.4?±?1.4 events. This result opens the door to precision measurements on anti-atoms, which can soon be subjected to the same techniques as developed for hydrogen. PMID:21085118

Andresen, G B; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jonsell, S; Jørgensen, L V; Kurchaninov, L; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; el Nasr, S Seif; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

2010-11-17

50

COLD TRAP  

DOEpatents

An improved linear-flow cold trap is designed for highvacuum applications such as mitigating back migration of diffusion pump oil moiecules. A central pot of liquid nitrogen is nested within and supported by a surrounding, vertical, helical coil of metai sheet, all enveloped by a larger, upright, cylindrical, vacuum vessel. The vertical interstices between successive turns of the coil afford lineal, axial, high-vacuum passages between open mouths at top and bottom of said vessel, while the coil, being cold by virtue of thermal contact of its innermost turn with the nitrogen pot, affords expansive proximate condensation surfaces. (AEC)

Milleron, N.

1963-03-12

51

VACUUM TRAP  

DOEpatents

An improved adsorption vacuum trap for use in vacuum systems was designed. The distinguishing feature is the placement of a plurality of torsionally deformed metallic fins within a vacuum jacket extending from the walls to the central axis so that substantially all gas molecules pass through the jacket will impinge upon the fin surfaces. T fins are heated by direct metallic conduction, thereby ol taining a uniform temperature at the adeorbing surfaces so that essentially all of the condensible impurities from the evacuating gas are removed from the vacuum system.

Gordon, H.S.

1959-09-15

52

The equivalence principle  

SciTech Connect

For the example of the motion of an accelerated charge it is shown that an inertial frame of reference in which there is a homogeneous static gravitational field with strength g is physically inequivalent to a uniformly accelerated frame of reference moving with acceleration -g with respect to the intertial frame of reference. It follows from this that the equivalence principle does not hold in the usual formulation. The widely held opinion that such a principle is the basis of the general theory of relativity is not entirely correct. Einstein`s theory of gravitation is based on an equivalence principle of a deeper content, which takes the form that the metric field g{sub uv} of a Riemannian space is declared to be a gravitational field. Such is the {open_quotes}natural formulation of the equivalence principle{close_quotes} at which Einstein subsequently arrived.

Logunov, A.A.; Mestvirishvili, M.A.; Chugreev, Yu.V.

1994-10-01

53

Trapping Electron Assisted Magnetic Recording  

Microsoft Academic Search

Moving towards 10 Tb\\/in2 areal density, finding a proper recording scheme with enough write-ability is the most challenging task of a magnetic recording system. Some recording schemes with enhanced write-ability, such as HAMR, MAMR, graded media, etc., have been proposed to achieve higher recording density. Here we propose a new alternative approach for enhanced writing-trapping electron assisted magnetic recording (TEAMR).

Tiejun Zhou; Zhimin Yuan; Siang Huei Leong; Boon Hao Low; Chun Lian Ong; Li Wang; Bo Liu; Choon Min Cheong; Shengbin Hu

2010-01-01

54

Task structure semantics through process algebra  

Microsoft Academic Search

The task structure diagramming technique can be used to graphically denote processspecifications. In task structure diagrams, sequential execution, iteration, choice and parallelismcan be expressed. In this paper task structure diagrams are extended with asynchronisation mechanism and a formal semantics is given by means of a translation toProcess Algebra. By using known techniques for proving equivalence of process specificationsin Process Algebra,

A. H. M. ter Hofstede; E. R. Nieuwland

1993-01-01

55

Steam-trap capacities  

Microsoft Academic Search

Factors that affect steam-trap capacity are listed and include: trap inlet pressure, trap discharge pressure, subcooling of inlet condensate, static head of condensate on trap, design of the trap, design of the piping. Some of the things that a user might look for in a steam pipe are examined: low installed cost, low maintenance cost, low cost of owning, and

1985-01-01

56

Achieving cold antiprotons in a Penning trap  

SciTech Connect

The current state of proton/electron trapping sensitivity at Washington requires only small numbers (less than or equal to 100) of anti p be trapped in order to achieve high signal to noise ratios. We therefore investigated a anti p trapping scheme based on stopping foils which, in the simplest case, require no auxiliary decelerator/cooler past a LEAR (or equivalent) stage. Cooling of the trapped particles could be accomplished via the damping provided by an external resistor as in all of the other experiments. The rate of this cooling would be rather low, even in the most ideal case, and likely would be much lower when the electrostatic anharmonicity of such a trap is realistically considered. We thereby examined a possible alternate cooling scheme, electron cooling with a buffer gas of cold electrons, in order to improve the cooling rate. 18 references.

Kells, W.; Gabrielse, G.; Helmerson, K.

1984-08-01

57

Comments on TNT Equivalence  

Microsoft Academic Search

The term ``TNT Equivalence`` is used throughout the explosives and related industries to compare the effects of the output of a given explosive to that of TNT. This is done for technical design reasons in scaling calculation such as for the prediction of blast waves, craters, and structural response, and is also used as a basis for government regulations controlling

1994-01-01

58

PATHOGEN EQUIVALENCY COMMITTEE (PEC)  

EPA Science Inventory

The U.S. Environmental Protection Agency created the PEC in 1985 to make recommendations to EPA and State managers on the equivalency of unproven sewage sludge disinfection technologies/processes to either a Process to Significantly Reduce Pathogens (PSRP) or a Process to Further...

59

The Interaction Equivalency Theorem  

ERIC Educational Resources Information Center

|This paper examines the key issues regarding The Interaction Equivalency Theorem posited by Anderson (2003a), which consists of the three interaction elements found in formal education courses among teacher, student, and content. It first examines the core concepts of the theorem and argues that two theses of different dimensions can be…

Miyazoe, Terumi; Anderson, Terry

2010-01-01

60

Biomonitoring Equivalents for triclosan  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite(s)

Kannan Krishnan; Michelle Gagné; Andy Nong; Lesa L. Aylward; Sean M. Hays

2010-01-01

61

Biomonitoring equivalents for hexachlorobenzene  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite

Lesa L. Aylward; Sean M. Hays; Michelle Gagné; Andy Nong; Kannan Krishnan

2010-01-01

62

Equivalent Colorings with "Maple"  

ERIC Educational Resources Information Center

Many counting problems can be modeled as "colorings" and solved by considering symmetries and Polya's cycle index polynomial. This paper presents a "Maple 7" program link http://users.tamuk.edu/kfdrc00/ that, given Polya's cycle index polynomial, determines all possible associated colorings and their partitioning into equivalence classes. These…

Cecil, David R.; Wang, Rongdong

2005-01-01

63

Equivalent Fractions Shoot  

NSDL National Science Digital Library

In this interactive game students are given a fraction to match to the equivalent fraction models that rotate around the screen. There are five levels of difficulty and each level has two modes, relaxed (ten problems, untimed) or timed(answer quickly and it increases your score). The goal is to get as many correct as possible.

2011-01-01

64

Geodesic Equivalence via Integrability  

Microsoft Academic Search

We suggest a construction that, given an orbital diffeomorphism between two Hamiltonian systems, produces integrals of them. We treat geodesic equivalence of metrics as the main example of it. In this case, the integrals commute; they are functionally independent if the eigenvalues of the tensor giag¯aj are all different; if the eigenvalues are all different at least at one point

Peter Topalov; Vladimir S. Matveev

2003-01-01

65

Equivalent Crystal Planes Animation  

NSDL National Science Digital Library

This is a 3-D animation of equivalent crystal planes. It shows the Miller indices linking nodes as a corresponding binary family within braces. This animation is approximately 13 seconds in length and would be useful for understanding the conceptual/imaginary planes have on the crystal behavior.

2009-07-22

66

Stability of functional equivalence and stimulus equivalence: effects of baseline reversals.  

PubMed Central

Functional equivalence and stimulus equivalence classes were established, reversed, and tested for stability with college students. Functional stimulus classes were established using a task in which students were trained to say nonsense words in the presence of arbitrarily assigned sets of symbols. Computer-controlled speech-recognition technology was used to record and analyze students' vocal responses for accuracy. After the establishment of stimulus classes was demonstrated with a transfer-of-function test, the effects of reversing selected baseline simple discriminations were assessed during an additional transfer-of-function test and a follow-up test that occurred several weeks later. With the same students, stimulus equivalence classes were established and demonstrated with computerized matching-to-sample procedures. The effects of reversing selected baseline conditional discriminations also were assessed during a postreversal equivalence test and a follow-up test. Both functional stimulus classes and stimulus equivalence were sensitive to contingency reversals, but the reversals with stimulus equivalence closses affected stimulus class organization whereas reversals with functional stimulus classes did not. Follow-up performances were largely consistent with the original baseline contingencies. The similarities and differences between stimulus equivalence and functional equivalence are related to the specific contingencies that select responding in the presence of the stimuli that form the classes.

Wirth, Oliver; Chase, Philip N

2002-01-01

67

Robot task space analyzer  

SciTech Connect

Many nuclear projects such as environmental restoration and waste management challenges involve radiation or other hazards that will necessitate the use of remote operations that protect human workers from dangerous exposures. Remote work is far more costly to execute than what workers could accomplish directly with conventional tools and practices because task operations are slow and tedious due to difficulties of remote manipulation and viewing. Decades of experience within the nuclear remote operations community show that remote tasks may take hundreds of times longer than hands-on work; even with state-of-the-art force- reflecting manipulators and television viewing, remote task performance execution is five to ten times slower than equivalent direct contact work. Thus the requirement to work remotely is a major cost driver in many projects. Modest improvements in the work efficiency of remote systems can have high payoffs by reducing the completion time of projects. Additional benefits will accrue from improved work quality and enhanced safety.

Hamel, W.R. [Univ. of Tennessee, Knoxville, TN (United States); Osborn, J. [Carnegie-Mellon Univ., Pittsburgh, PA (United States)

1997-12-01

68

Establishing Substantial Equivalence: Metabolomics  

NASA Astrophysics Data System (ADS)

Modern ‘metabolomic’ methods allow us to compare levels of many structurally diverse compounds in an automated fashion across a large number of samples. This technology is ideally suited to screening of populations of plants, including trials where the aim is the determination of unintended effects introduced by GM. A number of metabolomic methods have been devised for the determination of substantial equivalence. We have developed a methodology, using [1H]-NMR fingerprinting, for metabolomic screening of plants and have applied it to the study of substantial equivalence of field-grown GM wheat. We describe here the principles and detail of that protocol as applied to the analysis of flour generated from field plots of wheat. Particular emphasis is given to the downstream data processing and comparison of spectra by multivariate analysis, from which conclusions regarding metabolome changes due to the GM can be assessed against the background of natural variation due to environment.

Beale, Michael H.; Ward, Jane L.; Baker, John M.

69

zTrap: zebrafish gene trap and enhancer trap database  

PubMed Central

Background We have developed genetic methods in zebrafish by using the Tol2 transposable element; namely, transgenesis, gene trapping, enhancer trapping and the Gal4FF-UAS system. Gene trap constructs contain a splice acceptor and the GFP or Gal4FF (a modified version of the yeast Gal4 transcription activator) gene, and enhancer trap constructs contain the zebrafish hsp70l promoter and the GFP or Gal4FF gene. By performing genetic screens using these constructs, we have generated transgenic zebrafish that express GFP and Gal4FF in specific cells, tissues and organs. Gal4FF expression is visualized by creating double transgenic fish carrying a Gal4FF transgene and the GFP reporter gene placed downstream of the Gal4-recognition sequence (UAS). Further, the Gal4FF-expressing cells can be manipulated by mating with UAS effector fish. For instance, when fish expressing Gal4FF in specific neurons are crossed with the UAS:TeTxLC fish carrying the tetanus neurotoxin gene downstream of UAS, the neuronal activities are inhibited in the double transgenic fish. Thus, these transgenic fish are useful to study developmental biology and neurobiology. Description To increase the usefulness of the transgenic fish resource, we developed a web-based database named zTrap http://kawakami.lab.nig.ac.jp/ztrap/. The zTrap database contains images of GFP and Gal4FF expression patterns, and genomic DNA sequences surrounding the integration sites of the gene trap and enhancer trap constructs. The integration sites are mapped onto the Ensembl zebrafish genome by in-house Blat analysis and can be viewed on the zTrap and Ensembl genome browsers. Furthermore, zTrap is equipped with the functionality to search these data for expression patterns and genomic loci of interest. zTrap contains the information about transgenic fish including UAS reporter and effector fish. Conclusion zTrap is a useful resource to find gene trap and enhancer trap fish lines that express GFP and Gal4FF in desired patterns, and to find insertions of the gene trap and enhancer trap constructs that are located within or near genes of interest. These transgenic fish can be utilized to observe specific cell types during embryogenesis, to manipulate their functions, and to discover novel genes and cis-regulatory elements. Therefore, zTrap should facilitate studies on genomics, developmental biology and neurobiology utilizing the transgenic zebrafish resource.

2010-01-01

70

Comments on TNT Equivalence  

SciTech Connect

The term ``TNT Equivalence`` is used throughout the explosives and related industries to compare the effects of the output of a given explosive to that of TNT. This is done for technical design reasons in scaling calculation such as for the prediction of blast waves, craters, and structural response, and is also used as a basis for government regulations controlling the shipping, handling and storage of explosive materials, as well as for the siting and design of explosive facilities. TNT equivalence is determined experimentally by several different types of tests, the most common of which include: plate dent, ballistic mortar, trauzl, sand crush, and air blast. All of these tests do not necessarily measure the same output property of the sample explosive. As examples of this, some tests depend simply upon the CJ pressure, some depend upon the PV work in the CJ zone and in the Taylor wave behind the CJ plane, some are functions of the total work which includes that from secondary combustion in the air mixing region of the fireball and are acutely effected by the shape of the pressure-time profile of the wave. Some of the tests incorporate systematic errors which are not readily apparent, and which have a profound effect upon skewing the resultant data. Further, some of the tests produce different TNT Equivalents for the same explosive which are a function of the conditions at which the test is run. This paper describes the various tests used, discusses the results of each test and makes detailed commentary on what the test is actually measuring, how the results may be interpreted, and if and how these results can be predicted by first principals based calculations. Extensive data bases are referred to throughout the paper and used in examples for each point in the commentaries.

Cooper, P.W.

1994-07-01

71

Excitons in electrostatic traps  

NASA Astrophysics Data System (ADS)

We consider in-plane electrostatic traps for indirect excitons in coupled quantum wells, where the traps are formed by a laterally modulated gate voltage. An intrinsic obstacle for exciton confinement in electrostatic traps is an in-plane electric field that can lead to exciton dissociation. We propose a design to suppress the in-plane electric field and, at the same time, to effectively confine excitons in the electrostatic traps. We present calculations for various classes of electrostatic traps and experimental proof of principle for trapping of indirect excitons in electrostatic traps.

Hammack, A. T.; Gippius, N. A.; Yang, Sen; Andreev, G. O.; Butov, L. V.; Hanson, M.; Gossard, A. C.

2006-03-01

72

Task-Ambient Office Lighting.  

National Technical Information Service (NTIS)

A method is discussed for converting uniform office lighting systems to task-ambient lighting systems. The method requires only the use of a light meter and a mirror. A correlation between the method and equivalent sphere illumination is shown. Several ex...

W. Pierpoint

1980-01-01

73

Establishing Substantial Equivalence: Proteomics  

NASA Astrophysics Data System (ADS)

Wheat is a major crop in world agriculture and is consumed after processing into a range of food products. It is therefore of great importance to determine the consequences (intended and unintended) of transgenesis in wheat and whether genetically modified lines are substantially equivalent to those produced by conventional plant breeding. Proteomic analysis is one of several approaches which can be used to address these questions. Two-dimensional PAGE (2D PAGE) remains the most widely available method for proteomic analysis, but is notoriously difficult to reproduce between laboratories. We therefore describe methods which have been developed as standard operating procedures in our laboratory to ensure the reproducibility of proteomic analyses of wheat using 2D PAGE analysis of grain proteins.

Lovegrove, Alison; Salt, Louise; Shewry, Peter R.

74

Trapping polar molecules in an ac trap  

SciTech Connect

Polar molecules in high-field seeking states cannot be trapped in static traps as Maxwell's equations do not allow a maximum of the electric field in free space. It is possible to generate an electric field that has a saddle point by superposing an inhomogeneous electric field to an homogeneous electric field. In such a field, molecules are focused along one direction, while being defocused along the other. By reversing the direction of the inhomogeneous electric field the focusing and defocusing directions are reversed. When the fields are being switched back and forth at the appropriate rate, this leads to a net focusing force in all directions. We describe possible electrode geometries for creating the desired fields and discuss their merits. Trapping of {sup 15}ND{sub 3} ammonia molecules in a cylindrically symmetric ac trap is demonstrated. We present measurements of the spatial distribution of the trapped cloud as a function of the settings of the trap and compare these to both a simple model assuming a linear force and to full three-dimensional simulations of the experiment. With the optimal settings, molecules within a phase-space volume of 270 mm{sup 3} (m/s){sup 3} remain trapped. This corresponds to a trap depth of about 5 mK and a trap volume of about 20 mm{sup 3}.

Bethlem, Hendrick L. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); Laser Centre Vrije Universiteit, De Boelelaan 1081, NL-1081HV Amsterdam (Netherlands); Veldhoven, Jacqueline van [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); FOM-Institute for Plasmaphysics Rijnhuizen, P.O. Box 1207, NL-3430 BE Nieuwegein (Netherlands); Schnell, Melanie; Meijer, Gerard [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany)

2006-12-15

75

Micromotion in trapped atom-ion systems  

NASA Astrophysics Data System (ADS)

We examine the validity of the harmonic approximation, where the radio-frequency ion trap is treated as a harmonic trap, in the problem regarding the controlled collision of a trapped atom and a single trapped ion. This is equivalent to studying the effect of the micromotion since this motion must be neglected for the trapped ion to be considered as a harmonic oscillator. By applying the transformation of Cook and Shankland we find that the micromotion can be represented by two periodically oscillating operators. In order to investigate the effect of the micromotion on the dynamics of a trapped atom-ion system, we calculate (i) the coupling strengths of the micromotion operators by numerical integration and (ii) the quasienergies of the system by applying the Floquet formalism, a useful framework for studying periodic systems. It turns out that the micromotion is not negligible when the distance between the atom and the ion traps is shorter than a characteristic distance. Within this range the energy diagram of the system changes remarkably when the micromotion is taken into account, which leads to undesirable consequences for applications that are based on an adiabatic process of the trapped atom-ion system. We suggest a simple scheme for bypassing the micromotion effect in order to successfully implement a quantum controlled phase gate proposed previously and create an atom-ion macromolecule. The methods presented here are not restricted to trapped atom-ion systems and can be readily applied to studying the micromotion effect in any system involving a single trapped ion.

Nguyên, Lê Huy; Kalev, Amir; Barrett, Murray D.; Englert, Berthold-Georg

2012-05-01

76

Strong Equivalence for Causal Theories  

Microsoft Academic Search

Abstract: Strong equivalence is an important property for nonmonotonic formalisms, allowing safe local changes to a nonmonotonic theory. This paper considers strong equivalence for nonmonotonic causal theories of the kind introduced by McCain and Turner. Causal theories T_1 and T_2 are strongly equivalent if, for every causal theory T, T_1 union T and T_2 union T are equivalent (that is,

Hudson Turner

2004-01-01

77

The transfer of avoidance evoking functions through stimulus equivalence classes.  

PubMed

Recent research in the area of stimulus equivalence suggests that transfer of function via members of stimulus equivalence classes may have relevance to human emotional responding and the development and generalization of certain psychological disorders. This study investigated the transfer of avoidance evoking functions through equivalence classes. Eight subjects were trained in the necessary relations for two-four member stimulus equivalence classes to emerge. Next, using an on-baseline classical conditioning procedure, one member of one class was paired with shock while one member of the other class was presented without shock. Then, while subjects engaged a key-press task, a differential, signalled avoidance task was introduced wherein shock was avoided if a response occurred to the stimulus previously associated with shock. The remaining stimuli from both classes were then presented. The behavior of all eight subjects showed the differential transfer of the avoidance evoking function. The clinical and theoretical implications of the results are discussed. PMID:9327297

Augustson, E M; Dougher, M J

1997-09-01

78

Inductive Reasoning in Zambia, Turkey, and the Netherlands Establishing Cross-Cultural Equivalence.  

ERIC Educational Resources Information Center

|Administered tasks of inductive reasoning to 704 Zambian, 877 Turkish, and 632 Dutch students from the highest 2 grades of primary and the lowest 2 grades of secondary school. Results show strong evidence for structural equivalence and partial evidence for measurement unit equivalence, but did not support full score equivalence. (SLD)|

van de Vijver, Fons J. R.

2002-01-01

79

Biomonitoring equivalents for hexachlorobenzene.  

PubMed

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline. This study reviews available health-based exposure guidance values for hexachlorobenzene (HCB) from Health Canada, the United States Environmental Protection Agency (US EPA), the US Agency for Toxic Substances and Disease Registry (ATSDR) and World Health Organization (WHO). HCB liver tissue concentrations in chronic rodent bioassays and information on human elimination rates and tissue distribution of HCB were extrapolated to estimate serum lipid-adjusted HCB concentrations that are consistent with the exposure guidance values for HCB. Estimated serum lipid-adjusted HCB concentrations ranging from 16 to 250 ng/g lipid were consistent with non-cancer-based exposure guidance values from various agencies. Concentrations associated with cancer risk-specific doses at target risk levels of interest were also estimated. These BE values may be used as screening tools for evaluation of population biomonitoring data for HCB in a risk assessment context and can assist in prioritization of the potential need for additional risk assessment efforts for HCB relative to other chemicals. PMID:20547196

Aylward, Lesa L; Hays, Sean M; Gagné, Michelle; Nong, Andy; Krishnan, Kannan

2010-06-12

80

Steam-trap capacities  

SciTech Connect

Factors that affect steam-trap capacity are listed and include: trap inlet pressure, trap discharge pressure, subcooling of inlet condensate, static head of condensate on trap, design of the trap, design of the piping. Some of the things that a user might look for in a steam pipe are examined: low installed cost, low maintenance cost, low cost of owning, and maximum performance from the trapped equipment. The author notes that it is no coincidence that heating and ventilating engineers tend to use float-and-thermostative types of traps in large numbers, or that vendors of steam-heated equipment often specify inverted-bucket traps for use on their equipment. They may keep the equipment drained and operating at maximum capacity.

Monroe, E.S.

1985-04-15

81

Steam Trap Users' Guide.  

National Technical Information Service (NTIS)

Steam traps are an important element in the efficient operation of a steam system and in energy conservation. The high cost of producing and delivering steam mandates an effective steam trap inspection and maintenance program at all applicable naval activ...

D. M. Sneed J. C. King

1985-01-01

82

Biomonitoring Equivalents for triclosan.  

PubMed

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite(s) in a biological medium (blood, urine, or other medium) consistent with an existing health-based exposure guideline, and are derived by integrating available data on pharmacokinetics with existing chemical risk assessments. This study reviews available health-based exposure guidance values for triclosan based on recent evaluations from the United States Environmental Protection Agency (US EPA), the European Commission's Scientific Committee on Consumer Products (EC SCCP) and the Australian National Industrial Chemicals Notification and Assessment Scheme (NICNAS). BE values corresponding to the reference dose (RfD) or margin of safety (MOS) targets from these agencies were derived based on kinetic data (urinary excretion and plasma clearance) from human studies and measured blood concentration data in animal studies. Estimated BE values for urinary total triclosan (free plus conjugates) corresponding to the US EPA RfD and the EC-identified margin of safety target from the NOAEL are 6.4 and 2.6 mg/L, respectively (corresponding to 8.3 and 3.3mg/g creatinine, respectively). Plasma BE values corresponding to the US EPA, EC, and Australian NICNAS values are 0.3, 0.9, and 0.4 mg/L, respectively. These values may be used as screening tools for evaluation of population biomonitoring data for triclosan in a risk assessment context. PMID:20541577

Krishnan, Kannan; Gagné, Michelle; Nong, Andy; Aylward, Lesa L; Hays, Sean M

2010-06-10

83

Biomonitoring Equivalents for benzene.  

PubMed

Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline such as a reference dose (RfD) or tolerable daily intake (TDI). BE values can be used as a screening tool for the evaluation of population-based biomonitoring data in the context of existing risk assessments. This study reviews available health based risk assessments and exposure guidance values for benzene from the United States Environmental Protection Agency (US EPA), Texas Commission on Environmental Quality (TCEQ), California's Office of Environmental Health Hazard Assessment (OEHHA) and the Agency for Toxic Substances and Disease Registry (ATSDR) to derive BE values for benzene in blood and urine. No BE values were derived for any of the numerous benzene metabolites or hemoglobin and albumin adducts. Using existing physiologically based pharmacokinetic (PBPK) models, government risk assessment values were translated into corresponding benzene levels in blood assuming chronic steady-state exposures. BEs for benzene in urine were derived using measured correlations between benzene in urine with benzene in blood. The BE values for benzene in blood range from 0.04 to 1.29 ?g/L, depending upon the underlying non-cancer risk assessment used in deriving the BE. Sources of uncertainty relating to both the basis for the BE values and their use in evaluation of biomonitoring data, including the transience of the biomarkers relative to exposure frequency, are discussed. The BE values derived here can be used as screening tools for evaluation of population biomonitoring data for benzene in the context of the existing risk assessment and can assist in prioritization of the potential need for additional risk assessment efforts for benzene relative to other chemicals. PMID:22178585

Hays, Sean M; Pyatt, David W; Kirman, Chris R; Aylward, Lesa L

2011-12-09

84

Biomonitoring equivalents for deltamethrin.  

PubMed

Measured concentrations of chemicals in blood or urine in biomonitoring studies provide an integrated reflection of exposures to chemicals via multiple routes and pathways. The potential significance of the measured concentrations of chemicals in the context of existing toxicology data and risk assessments can be assessed if chemical-specific quantitative screening criteria are available. This work presents the derivation of Biomonitoring Equivalents (BEs) for deltamethrin, a synthetic Type II pyrethroid. BEs are estimates of biomarker concentrations that are consistent with risk assessment-based exposure guidance values such as reference doses or acceptable daily intakes. BE values were derived for deltamethrin based on two biomarkers: deltamethrin in plasma and 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid (DBCA), a specific metabolite, in urine. BE values for deltamethrin in plasma were based on extrapolation from measured deltamethrin concentrations in plasma in rats under conditions consistent with the Point of Departure in the critical study underlying the USEPA RfD. BE values for DBCA in urine were derived based on pharmacokinetic data from a study in human volunteers on the urinary excretion of deltamethrin and metabolites. BE values for deltamethrin in plasma corresponding to the USEPA RfD for adults and children are 20 and 2?g/L, respectively. BE values for DBCA in urine corresponding to the adult and child-specific RfDs are 50 and 7?g/L, respectively. The urinary BE value corresponding to the ADI established by the European Commission and the Joint Meeting on Pesticide Residues is 60?g/L (as DBCA in urine). These values can be used to screen biomonitoring data in the context of current risk assessments for detlamethrin. PMID:21466827

Aylward, Lesa L; Krishnan, Kannan; Kirman, Christopher R; Nong, Andy; Hays, Sean M

2011-04-03

85

A new hummingbird trap  

Microsoft Academic Search

New capturing methods are constantly developed to optimize field work efforts in scientific research. This paper describes the design and construction of a new hummingbird trap, called the Ruschi net trap. It consists of a circular screen lid attached to a frame and a cylindrical screen bag that is manually pulled to trap the hummingbird while it is feeding. The

Piero A. Ruschi

86

Thermostatic steam traps  

Microsoft Academic Search

A thermostatic steam trap is described comprising: a passageway for fluid flow; two connections constituting opposite ends of the passageway; a valve that opens and closes the trap having a valve seat disposed in the passageway; and a temperature-responsive element carrying a movable part of the valve that co-operates with the valve seat to open and close the trap; either

Dewhirst

1987-01-01

87

A Better Fly Trap  

NSDL National Science Digital Library

In this activity, learners observe fly behavior and then build a flytrap. They make more observations, compare the effectiveness of different traps, and modify their traps to increase their effectiveness. In doing so, learners consider what variables make for an effective trap as well as learning how to study the behavior of an animal. Even pesky flies provide an interesting challenge.

Science, Lawrence H.

1979-01-01

88

Trap centers in molybdates  

NASA Astrophysics Data System (ADS)

Charge carrier trapping centers have been studied in molybdates CaMoO4, SrMoO4 and PbMoO4 with the scheelite crystal structure as well as in ZnMoO4, which crystallize in a-ZnMoO4 structural type. The trap parameters such as activation energies and frequency factors have been determined. It is shown for the first time that both electrons and holes are trapped by the elements of regular crystal structure in ZnMoO4. The effect of the charge carrier trapping on luminescence properties is demonstrated. Potential influence of the traps on the scintillation process is discussed.

Spassky, D. A.; Nagirnyi, V.; Mikhailin, V. V.; Savon, A. E.; Belsky, A. N.; Laguta, V. V.; Buryi, M.; Galashov, E. N.; Shlegel, V. N.; Voronina, I. S.; Zadneprovski, B. I.

2013-10-01

89

Equivalence of kinetic theories of Bose-Einstein condensation  

NASA Astrophysics Data System (ADS)

We discuss the equivalence of two nonequilibrium kinetic theories that describe the evolution of a dilute, Bose-Einstein condensed atomic gas in a harmonic trap. The second-order kinetic equations of Walser et al. [Phys. Rev. A 63, 013607 (2001)] reduce to the Gross-Pitaevskii equation and the quantum Boltzmann equation in the low- and high-temperature limits, respectively. These kinetic equations thus describe the system in equilibrium (finite temperature) as well as in nonequilibrium (real time). We have found this theory to be equivalent to the nonequilibrium Green's function approach originally proposed by Kadanoff and Baym and more recently applied to inhomogeneous trapped systems by Imamovi?-Tomasovi? and Griffin [in Progress in Nonequilibrium Green's Functions, edited by M. Bonitz (World Scientific, Singapore, 2000), p. 404].

Wachter, J.; Walser, R.; Cooper, J.; Holland, M.

2001-11-01

90

Improvements to Combinational Equivalence Checking  

Microsoft Academic Search

The paper explores several ways to improve the speed and capacity of combinational equivalence checking based on Boolean satisfiability (SAT). State-of-the-art methods use simulation and BDD\\/SAT sweeping on the input side (i.e. proving equivalence of some internal nodes in a topological order), interleaved with attempts to run SAT on the output (i.e. proving equivalence of the output to constant 0).

A. Mishchenko; S. Chatterjee; R. Brayton; N. Een

2006-01-01

91

Equivalence Principle and Gravitational Redshift  

SciTech Connect

We investigate leading order deviations from general relativity that violate the Einstein equivalence principle in the gravitational standard model extension. We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter-wave, microwave, optical, and Moessbauer clock tests, yields comprehensive limits on spin-independent Einstein equivalence principle-violating standard model extension terms at the 10{sup -6} level.

Hohensee, Michael A.; Chu, Steven; Mueller, Holger [Department of Physics, University of California, Berkeley, California 94720 (United States); Peters, Achim [Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany)

2011-04-15

92

On Equivalent and Non-Equivalent Definitions: Part 2.  

ERIC Educational Resources Information Center

Addresses the definitions of several mathematical concepts and the relationships between them based on a theoretical framework presented in the first part. Presents two examples of mathematical activities on equivalent and non-equivalent definitions constructed in the context of professional development workshops for mathematics teachers.…

Leikin, Roza; Winicki-Landman, Greisy

2000-01-01

93

Biomonitoring Equivalents for inorganic arsenic  

Microsoft Academic Search

This paper presents Biomonitoring Equivalents (BEs) for inorganic arsenic. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline, and are derived by integrating available data on pharmacokinetics with existing chemical risk assessments. This

Sean M. Hays; Lesa L. Aylward; Michelle Gagné; Andy Nong; Kannan Krishnan

2010-01-01

94

Testing Model Nesting and Equivalence  

Microsoft Academic Search

When using existing technology, it can be hard or impossible to determine whether two structural equation models that are being considered may be nested. There is also no routine technology for evaluating whether two very different structural models may be equivalent. A simple nesting and equivalence testing (NET) procedure is proposed that uses random sample and model-reproduced moment matrices to

Peter M. Bentler; Albert Satorra

2010-01-01

95

Testing Model Nesting and Equivalence  

ERIC Educational Resources Information Center

|When using existing technology, it can be hard or impossible to determine whether two structural equation models that are being considered may be nested. There is also no routine technology for evaluating whether two very different structural models may be equivalent. A simple nesting and equivalence testing (NET) procedure is proposed that uses…

Bentler, Peter M.; Satorra, Albert

2010-01-01

96

Underdetermination, realism and empirical equivalence  

Microsoft Academic Search

Are theories 'underdetermined by the evidence' in a ny way that should worry the scientific realist? I argue that no convincing reason has been given for thinking so. A crucial distinction is drawn between data equivalen ce and empirical equivalence. Duhem showed that it is always possible to produce a data equivalent rival to any accepted scientific theory. But there

John Worrall

2011-01-01

97

Trap style influences wild pig behavior and trapping success  

USGS Publications Warehouse

Despite the efforts of many natural resource professionals, wild pig (Sus scrofa) populations are expanding in many areas of the world. Although many creative techniques for controlling pig populations are being explored, trapping has been and still is themost commonly usedmethod of population control formany public and private land managers. We conducted an observational study to examine the efficiency of 2 frequently used trap styles: a small, portable box-style trap and a larger, semi-permanent, corral-style trap.We used game cameras to examine patterns of trap entry by wild pigs around each style of trap, and we conducted a trapping session to compare trapping success between trap styles. Adult female and juvenile wild pigs entered both styles of trap more readily than did adult males, and adult males seemed particularly averse to entering box traps. Less than 10% of adult male visits to box traps resulted in entries, easily the least percentage of any class at any style of trap. Adult females entered corral traps approximately 2.2 times more often per visit than box traps and re-entered corral traps >2 times more frequently. Juveniles entered and reentered both box and corral traps at similar rates. Overall (all-class) entry-per-visit rates at corral traps (0.71) were nearly double that of box traps (0.37). Subsequent trapping data supported these preliminary entry data; the capture rate for corral traps was >4 times that of box traps. Our data suggest that corral traps are temporally and economically superior to box traps with respect to efficiency; that is, corral traps effectively trap more pigs per trap night at a lower cost per pig than do box traps. ?? 2011 The Wildlife Society.

Williams, B. L.; Holtfreter, R. W.; Ditchkoff, S. S.; Grand, J. B.

2011-01-01

98

Steam traps: simple but important  

SciTech Connect

An overeview of various steam trap designs and their characteristics is presented. The basic uses of each design are discussed. The need for steam traps is reviewed and it is stressed that steam traps (which do not require operator attendance) is the simplest and most cost effective means of allowing condensate to drain away from critical areas. The four basic types of steam traps are described. These are: (1) inverted bucket traps; (2) float traps; (3) thermodynamic traps; and (4) condensate load traps. Advantages and disadvantages of each type of steam trap are discussed as well as cost considerations. Considerations in usage of each type of trap are pointed out. (MJJ)

Hammond, H.

1981-03-01

99

Ecological and evolutionary traps  

USGS Publications Warehouse

Organisms often rely on environmental cues to make behavioral and life-history decisions. However, in environments that have been altered suddenly by humans, formerly reliable cues might no longer be associated with adaptive outcomes. In such cases, organisms can become 'trapped' by their evolutionary responses to the cues and experience reduced survival or reproduction. Ecological traps occur when organisms make poor habitat choices based on cues that correlated formerly with habitat quality. Ecological traps are part of a broader phenomenon, evolutionary traps, involving a dissociation between cues that organisms use to make any behavioral or life-history decision and outcomes normally associated with that decision. A trap can lead to extinction if a population falls below a critical size threshold before adaptation to the novel environment occurs. Conservation and management protocols must be designed in light of, rather than in spite of, the behavioral mechanisms and evolutionary history of populations and species to avoid 'trapping' them.

Schlaepfer, M.A.; Runge, M.C.; Sherman, P.W.

2002-01-01

100

Trapping in complex networks  

NASA Astrophysics Data System (ADS)

We investigate the trapping problem in Erd?s-Rényi (ER) and scale-free (SF) networks. We calculate the evolution of the particle density ?(t) of random walkers in the presence of one or multiple traps with concentration c. We show using theory and simulations that in ER networks, while for short times ?(t)~exp(-Act), for longer times ?(t) exhibits a more complex behavior, with explicit dependence on both the number of traps and the size of the network. In SF networks we reveal the significant impact of the trap's location: ?(t) is drastically different when a trap is placed on a random node compared to the case of the trap being on the node with the maximum connectivity. For the latter case we find ?(t) propto exp [-At/N?-2/?-1 langlekrangle] for all ?> 2, where ? is the exponent of the degree distribution P(k)~k- ?.

Kittas, A.; Carmi, S.; Havlin, S.; Argyrakis, P.

2008-11-01

101

Microfabricated ion trap array  

DOEpatents

A microfabricated ion trap array, comprising a plurality of ion traps having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale ion traps to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The reduced electrode voltage enables integration of the microfabricated ion trap array with on-chip circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of the microfabricated ion trap array can be realized in truly field portable, handheld microanalysis systems.

Blain, Matthew G. (Albuquerque, NM); Fleming, James G. (Albuquerque, NM)

2006-12-26

102

Excitons in electrostatic traps  

Microsoft Academic Search

We consider in-plane electrostatic traps for indirect excitons in coupled quantum wells, where the traps are formed by a laterally modulated gate voltage. An intrinsic obstacle for exciton confinement in electrostatic traps is an in-plane electric field that can lead to exciton dissociation. We propose a design to suppress the in-plane electric field and, at the same time, to effectively

A. T. Hammack; N. A. Gippius; Sen Yang; G. O. Andreev; L. V. Butov; M. Hanson; A. C. Gossard

2006-01-01

103

Permanent magnetic trapping  

NASA Astrophysics Data System (ADS)

It is shown that the global nature of trapped particle motion in phase space makes it entirely plausible that particles with pitch angles near 90 deg are trapped for extremely long times, probably indefinitely. The long observed lifetimes of trapped particles can immediately be accounted for by this former population. For particles with low pitch angles an 'overstability' develops which serves to produce rapid variations in pitch angle and, presumably, random walk into the loss cone.

Michel, F. C.

1980-02-01

104

Understanding Equivalence and Noninferiority Testing  

PubMed Central

Increasingly, the goal of many studies is to determine if new therapies have equivalent or noninferior efficacies to the ones currently in use. These studies are called equivalence/noninferiority studies, and the statistical methods for their analysis require only simple modifications to the traditional hypotheses testing framework. Nevertheless, important and subtle issues arise with the application of such methods. This article describes the concepts and statistical methods involved in testing equivalence/noninferiority. The aim is to enable the clinician to understand and critically assess the growing number of articles utilizing such methods.

Nowacki, Amy S.

2010-01-01

105

Optical metrics and projective equivalence  

NASA Astrophysics Data System (ADS)

Trajectories of light rays in a static spacetime are described by unparametrized geodesics of the Riemannian optical metric associated with the Lorentzian spacetime metric. We investigate the uniqueness of this structure and demonstrate that two different observers, moving relative to one another, who both see the Universe as static may determine the geometry of the light rays differently. More specifically, we classify Lorentzian metrics admitting more than one hyper-surface orthogonal timelike Killing vector and analyze the projective equivalence of the resulting optical metrics. These metrics are shown to be projectively equivalent up to diffeomorphism if the static Killing vectors generate a group SL(2,R), but not projectively equivalent in general. We also consider the cosmological C metrics in Einstein-Maxwell theory and demonstrate that optical metrics corresponding to different values of the cosmological constant are projectively equivalent.

Casey, Stephen; Dunajski, Maciej; Gibbons, Gary; Warnick, Claude

2011-04-01

106

Toxicity Equivalency Factors for PCBs.  

National Technical Information Service (NTIS)

In December 1990 the U.S. Environmental Protection Agency sponsored a workshop to discuss the applicability of an interim 'toxicity equivalency factor' (TEF) approach to assessing risks posed by exposures to complex mixtures of polychlorinated biphenyls (...

D. Barnes A. Alford-Stevens L. Birnbaum F. W. Kutz W. Wood

1991-01-01

107

Motorized gas trap  

Microsoft Academic Search

A gas trap is claimed which is used to separate at least a portion of the gases entrained in drilling fluids used in an oil well drilling operation. It is associated with the shale shaker box and an analyzer such as a hot wire analyzer. The gas trap includes a receptacle or a can vertically adjustably supported from the shaker

Ratcliff

1982-01-01

108

Steam trap monitor  

Microsoft Academic Search

A steam trap monitor positioned downstream of a steam trap in a closed steam system includes a first sensor (a hot finger) for measuring the energy of condensate and a second sensor (a cold finger) for measuring the total energy of condensate and steam in the line. The hot finger includes one or more thermocouples for detecting condensate level and

Ryan

1987-01-01

109

Steam trap monitor  

Microsoft Academic Search

For use in a closed steam system, apparatus coupled to a stream trap by means of a pipe and located downstream therefrom for monitoring the steam trap, the apparatus comprising: first sensing means in the pipe for determining the heat energy of a condensate flow in the pipe; second sensing means in the pipe for determining the heat energy of

Ryan

1988-01-01

110

Steam trap monitor  

Microsoft Academic Search

A steam trap monitor positioned downstream of a steam trap in a closed steam system includes a first sensor (the combination of a hot finger and thermocouple well) for measuring the energy of condensate and a second sensor (a cold finger) for measuring the total energy of condensate and steam in the line. The hot finger includes one or more

Ryan; Michael J

1988-01-01

111

Thermostatic steam traps  

SciTech Connect

A thermostatic steam trap is described comprising: a passageway for fluid flow; two connections constituting opposite ends of the passageway; a valve that opens and closes the trap having a valve seat disposed in the passageway; and a temperature-responsive element carrying a movable part of the valve that co-operates with the valve seat to open and close the trap; either of the connections comprising an inlet to the trap for the fluid flow with the other being an outlet from the trap for this flow. The trap selectively connects in a steam flow line either (A) with the passageway permanently open to the steam line and the valve opening and closing the passageway downstream of the element to atmosphere to discharge condensate from the trap at a temperature close to saturated steam temperature, or (B) with the passageway permanently open to atmosphere and the valve disposed upstream of the element to discharge condensate from the trap at a temperature significantly below steam temperature.

Dewhirst, K.

1987-07-21

112

Neutrophil extracellular traps  

PubMed Central

Cancers prime neutrophils to release extracellular DNA traps through the systemic release of granulocyte colony-stimulating factor (G-CSF). We recently showed that these circulating neutrophil extracellular traps (NETs) promote the establishment of a pro-thrombotic state. The role of NETs in cancer biology and tumor progression may prove much more than an unfortunate side effect of cancer.

Demers, Melanie; Wagner, Denisa D.

2013-01-01

113

Optical trapping of nanoparticles.  

PubMed

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping and manipulating small biological particles. Ashkin and co-workers first demonstrated optical tweezers using a single focused beam. The single beam trap can be described accurately using the perturbative gradient force formulation in the case of small Rayleigh regime particles. In the perturbative regime, the optical power required for trapping a particle scales as the inverse fourth power of the particle size. High optical powers can damage dielectric particles and cause heating. For instance, trapped latex spheres of 109 nm in diameter were destroyed by a 15 mW beam in 25 sec, which has serious implications for biological matter. A self-induced back-action (SIBA) optical trapping was proposed to trap 50 nm polystyrene spheres in the non-perturbative regime. In a non-perturbative regime, even a small particle with little permittivity contrast to the background can influence significantly the ambient electromagnetic field and induce a large optical force. As a particle enters an illuminated aperture, light transmission increases dramatically because of dielectric loading. If the particle attempts to leave the aperture, decreased transmission causes a change in momentum outwards from the hole and, by Newton's Third Law, results in a force on the particle inwards into the hole, trapping the particle. The light transmission can be monitored; hence, the trap can become a sensor. The SIBA trapping technique can be further improved by using a double-nanohole structure. The double-nanohole structure has been shown to give a strong local field enhancement. Between the two sharp tips of the double-nanohole, a small particle can cause a large change in optical transmission, thereby inducing a large optical force. As a result, smaller nanoparticles can be trapped, such as 12 nm silicate spheres and 3.4 nm hydrodynamic radius bovine serum albumin proteins. In this work, the experimental configuration used for nanoparticle trapping is outlined. First, we detail the assembly of the trapping setup which is based on a Thorlabs Optical Tweezer Kit. Next, we explain the nanofabrication procedure of the double-nanohole in a metal film, the fabrication of the microfluidic chamber and the sample preparation. Finally, we detail the data acquisition procedure and provide typical results for trapping 20 nm polystyrene nanospheres. PMID:23354173

Bergeron, Jarrah; Zehtabi-Oskuie, Ana; Ghaffari, Saeedeh; Pang, Yuanjie; Gordon, Reuven

2013-01-15

114

Optically programmable excitonic traps  

PubMed Central

With atomic systems, optically programmed trapping potentials have led to remarkable progress in quantum optics and quantum information science. Programmable trapping potentials could have a similar impact on studies of semiconductor quasi-particles, particularly excitons. However, engineering such potentials inside a semiconductor heterostructure remains an outstanding challenge and optical techniques have not yet achieved a high degree of control. Here, we synthesize optically programmable trapping potentials for indirect excitons of bilayer heterostructures. Our approach relies on the injection and spatial patterning of charges trapped in a field-effect device. We thereby imprint in-situ and on-demand electrostatic traps into which we optically inject cold and dense ensembles of excitons. This technique creates new opportunities to improve state-of-the-art technologies for the study of collective quantum behavior of excitons and also for the functionalisation of emerging exciton-based opto-electronic circuits.

Alloing, Mathieu; Lemaitre, Aristide; Galopin, Elisabeth; Dubin, Francois

2013-01-01

115

Optical trapping and binding  

NASA Astrophysics Data System (ADS)

The phenomenon of light's momentum was first observed in the laboratory at the beginning of the twentieth century, and its potential for manipulating microscopic particles was demonstrated by Ashkin some 70 years later. Since that initial demonstration, and the seminal 1986 paper where a single-beam gradient-force trap was realized, optical trapping has been exploited as both a rich example of physical phenomena and a powerful tool for sensitive measurement. This review outlines the underlying theory of optical traps, and explores many of the physical observations that have been made in such systems. These phenomena include ‘optical binding’, where trapped objects interact with one another through the trapping light field. We also discuss a number of the applications of ‘optical tweezers’ across the physical and life sciences, as well as covering some of the issues involved in constructing and using such a tool.

Bowman, Richard W.; Padgett, Miles J.

2013-02-01

116

Optically programmable excitonic traps  

NASA Astrophysics Data System (ADS)

With atomic systems, optically programmed trapping potentials have led to remarkable progress in quantum optics and quantum information science. Programmable trapping potentials could have a similar impact on studies of semiconductor quasi-particles, particularly excitons. However, engineering such potentials inside a semiconductor heterostructure remains an outstanding challenge and optical techniques have not yet achieved a high degree of control. Here, we synthesize optically programmable trapping potentials for indirect excitons of bilayer heterostructures. Our approach relies on the injection and spatial patterning of charges trapped in a field-effect device. We thereby imprint in-situ and on-demand electrostatic traps into which we optically inject cold and dense ensembles of excitons. This technique creates new opportunities to improve state-of-the-art technologies for the study of collective quantum behavior of excitons and also for the functionalisation of emerging exciton-based opto-electronic circuits.

Alloing, Mathieu; Lemaître, Aristide; Galopin, Elisabeth; Dubin, François

2013-04-01

117

Visuospatial tasks suppress craving for cigarettes.  

PubMed

The Elaborated Intrusion (EI) theory of desire posits that visual imagery plays a key role in craving. We report a series of experiments testing this hypothesis in a drug addiction context. Experiment 1 showed that a mental visual imagery task with neutral content reduced cigarette craving in abstaining smokers, but that an equivalent auditory task did not. The effect of visual imagery was replicated in Experiment 2, which also showed comparable effects of non-imagery visual working memory interference. Experiment 3 showed that the benefit of visual over auditory interference was not dependent upon imagery being used to induce craving. Experiment 4 compared a visuomotor task, making shapes from modeling clay, with a verbal task (counting back from 100), and again showed a benefit of the visual over the non-visual task. We conclude that visual imagery supports craving for cigarettes. Competing imagery or visual working memory tasks may help tackle craving in smokers trying to quit. PMID:20189549

May, Jon; Andrade, Jackie; Panabokke, Nathalie; Kavanagh, David

2010-02-07

118

Holographic optical trapping  

SciTech Connect

Holographic optical tweezers use computer-generated holograms to create arbitrary three-dimensional configurations of single-beam optical traps that are useful for capturing, moving, and transforming mesoscopic objects. Through a combination of beam-splitting, mode-forming, and adaptive wavefront correction, holographic traps can exert precisely specified and characterized forces and torques on objects ranging in size from a few nanometers to hundreds of micrometers. Offering nanometer-scale spatial resolution and real-time reconfigurability, holographic optical traps provide unsurpassed access to the microscopic world and have found applications in fundamental research, manufacturing, and materials processing.

Grier, David G.; Roichman, Yael

2006-02-10

119

Simplifying steam trap selection  

SciTech Connect

In the current economic world order, there is an obligation to eliminate waste and conserve economic and natural resources. One trap blowing 100-lb of steam through a 1/4-in. orifice can cost more than $12,000 a year in wasted energy. Richard J. Debat of Armstrong International, Inc. explains the operating principles of the four basic types of steam traps as the first step in simplifying the selection process so the right trap can be specified for a given application.

Debat, R.J. (Armstrong International, Inc., Three Rivers, MI (United States))

1994-01-01

120

ROBOSPECT: Automated Equivalent Width Measurement  

NASA Astrophysics Data System (ADS)

We present ROBOSPECT, a new code to automatically measure and deblend line equivalent widths for both absorption and emission spectra. We test the accuracy of these measurements against simulated spectra as well as manual equivalent width measurements of five stellar spectra over a range of signal-to-noise values and a set of long slit emission spectra. We find that ROBOSPECT accurately matches both the synthetic and manual measurements, with scatter consistent with the expectations based on the data quality and the results of Cayrel.

Waters, Christopher Z.; Hollek, Julie K.

2013-09-01

121

Sievert, gray and dose equivalent.  

PubMed

The concepts of physical quantity and physical units of measurement are presented. The relations between quantities, the names and symbols for SI (International System) base units, derived units and special names of SI units are illustrated. From the definition of the radiation quantity dose equivalent, the SI unit for this quantity is shown to be dimensionally identical with the joule per kilogram. The sievert (Sv) is the special (restricted) name for the SI unit of the quantity dose equivalent, with 1 Sv = 1 J/kg. PMID:6668293

Pfalzner, P M

1983-12-01

122

Trapping and Probing Antihydrogen  

ScienceCinema

Precision spectroscopy of antihydrogen is a promising path to sensitive tests of CPT symmetry. The most direct route to achieve this goal is to create and probe antihydrogen in a magnetic minimum trap. Antihydrogen has been synthesized and trapped for 1000s at CERN by the ALPHA Collaboration. Some of the challenges associated with achieving these milestones will be discussed, including mixing cryogenic positron and antiproton plasmas to synthesize antihydrogen with kinetic energy less than the trap potential of .5K. Recent experiments in which hyperfine transitions were resonantly induced with microwaves will be presented. The opportunity for gravitational measurements in traps based on detailed studies of antihydrogen dynamics will be described. The talk will conclude with a discussion future antihydrogen research that will use a new experimental apparatus, ALPHA-I.

123

Versatile electrostatic trap  

SciTech Connect

A four electrode electrostatic trap geometry is demonstrated that can be used to combine a dipole, quadrupole, and hexapole field. A cold packet of {sup 15}ND{sub 3} molecules is confined in both a purely quadrupolar and hexapolar trapping field and additionally, a dipole field is added to a hexapole field to create either a double-well or a donut-shaped trapping field. The profile of the {sup 15}ND{sub 3} packet in each of these four trapping potentials is measured, and the dependence of the well-separation and barrier height of the double-well and donut potential on the hexapole and dipole term are discussed.

Veldhoven, Jacqueline van [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); FOM-Institute for Plasmaphysics Rijnhuizen, P.O. Box 1207, NL-3430 BE Nieuwegein (Netherlands); Bethlem, Hendrick L. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); Laser Centre Vrije Universiteit Amsterdam, de Boelelaan 1081, NL-1081 HV Amsterdam (Netherlands); Schnell, Melanie; Meijer, Gerard [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany)

2006-06-15

124

Single beam acoustic trapping  

PubMed Central

A single beam acoustic device, with its relatively simple scheme and low intensity, can trap a single lipid droplet in a manner similar to optical tweezers. Forces in the order of hundreds of nanonewtons direct the droplet toward the beam focus, within the range of hundreds of micrometers. This trapping method, therefore, can be a useful tool for particle manipulation in areas where larger particles or forces are involved.

Lee, Jungwoo; Teh, Shia-Yen; Lee, Abraham; Kim, Hyung Ham; Lee, Changyang; Shung, K. Kirk

2009-01-01

125

Structural traps 5  

SciTech Connect

This book contains studies of oil and gas fields that are mainly structural in nature. Stratigraphy controls the extend of the reservoir in the traps of several fields, but overall, the main trapping features within the group of fields in this volume are structural. Fields covered in this volume include: Endicott Field, Point Arguello Field, West Puerto Chiquito Field, Dukhan Field, Sendji Field, Ruston Field, Raudhatain Field, Hassi Messaoud Field, Snapper Field, Tirrawarra Field, and Sacha Field.

Foster, N.H.; Beaumont, E.A.

1991-01-01

126

Simplifying steam trap selection  

Microsoft Academic Search

In the current economic world order, there is an obligation to eliminate waste and conserve economic and natural resources. One trap blowing 100-lb of steam through a 1\\/4-in. orifice can cost more than $12,000 a year in wasted energy. Richard J. Debat of Armstrong International, Inc. explains the operating principles of the four basic types of steam traps as the

Debat

1994-01-01

127

50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.  

Code of Federal Regulations, 2012 CFR

...limits and trap tag requirements for vessels fishing with lobster traps. 697.19 Section...limits and trap tag requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish in any...

2012-10-01

128

50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.  

Code of Federal Regulations, 2011 CFR

...limits and trap tag requirements for vessels fishing with lobster traps. 697.19 Section...limits and trap tag requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish in any...

2011-10-01

129

Using Machine Translation Evaluation Techniques to Determine Sentence-level Semantic Equivalence  

Microsoft Academic Search

The task of machine translation (MT) evaluation is closely related to the task of sentence-level semantic equiv- alence classification. This paper in- vestigates the utility of applying stan- dard MT evaluation methods (BLEU, NIST, WER and PER) to building clas- sifiers to predict semantic equivalence and entailment. We also introduce a novel classification method based on PER which leverages part

Andrew Finch; Young-Sook Hwang; Eiichiro Sumita

130

USEPA PATHOGEN EQUIVALENCY COMMITTEE RETREAT  

EPA Science Inventory

The Pathogen Equivalency Committee held its retreat from September 20-21, 2005 at Hueston Woods State Park in College Corner, Ohio. This presentation will update the PEC’s membership on emerging pathogens, analytical methods, disinfection techniques, risk analysis, preparat...

131

Foreword: Biomonitoring Equivalents Special Issue  

Microsoft Academic Search

The challenge of interpreting results of biomonitoring for environmental chemicals in humans is highlighted in this Foreword to the Biomonitoring Equivalents (BEs) special issue of Regulatory Toxicology and Pharmacology. There is a pressing need to develop risk-based tools in order to empower scientists and health professionals to interpret and communicate the significance of human biomonitoring data. The BE approach, which

R. A. Becker; B SONAWANE

2008-01-01

132

Acquired Equivalence Changes Stimulus Representations  

ERIC Educational Resources Information Center

Acquired equivalence is a paradigm in which generalization is increased between two superficially dissimilar stimuli (or antecedents) that have previously been associated with similar outcomes (or consequents). Several possible mechanisms have been proposed, including changes in stimulus representations, either in the form of added associations or…

Meeter, M.; Shohamy, D.; Myers, C. E.

2009-01-01

133

Equivalent Norms for Sobolev Spaces.  

National Technical Information Service (NTIS)

The equivalence of the usual norm in the Sobolev Space (W sub 0, superscript m,p)(G) and the norm obtained by using only the highest (i.e. m'th) order partial derivatives is established for a suitably restricted class of quasicylindrical, unbounded domain...

R. A. Adams

1969-01-01

134

On Fractional Programming and Equivalence.  

National Technical Information Service (NTIS)

Under fairly general conditions, a nonlinear fractional program, where the function to be maximized has the form f(x)/g(x), is shown to be equivalent to a nonlinear program not involving fractions. The latter program is not generally a convex program, but...

B. D. Craven B. Mond

1975-01-01

135

Equivalent Linear Logistic Test Models.  

ERIC Educational Resources Information Center

|Discusses the Linear Logistic Test Model (LLTM) and demonstrates that there are many equivalent ways to specify a model. Analyzed a real data set (300 responses to 5 analogies) using a Lagrange multiplier test for the specification of the model, and demonstrated that there may be many ways to change the specification of an LLTM and achieve the…

Bechger, Timo M.; Verstralen, Huub H. F. M.; Verhelst, Norma D.

2002-01-01

136

Multiple Functions in Equivalence Classes  

ERIC Educational Resources Information Center

Four experiments examined the effects of training a "drawing" response to each of three stimuli in a 5-member equivalence class. In Experiment 1 the stimuli were an arbitrary word, a shape, or a mathematical symbol. Subjects then were trained to draw a separate component of a stickman at each of the 3 stimuli. Subsequent tests for function…

McVeigh, Brian; Keenan, Mickey

2009-01-01

137

On the Einstein equivalence principle  

SciTech Connect

The Einstein equivalence principle, the cornerstone of our present day understanding of gravity, is used to explore a deeper connection between the deflection of starlight by a spinning object and the Lense-Thirring dragging of inertial frames. It is also noted that experiment has not established that the gravitomagnetic coupling to currents of particle rest-mass energy, to currents of electromagnetic energy, and to currents of all other types of energy are identical as predicted by the Einstein equivalence principle. The detailed analysis of how atomic physics experiments originated by Hughes and by Drever can constrain such possible violations of the Einstein equivalence principle is given. Atomic clocks are also important tools used to test local Lorentz invariance and hence one important aspect of Einstein equivalence principle. The sensitivity of atomic clocks to preferred-frame effects is studied here for the first time, and the behavior of the hydrogen-maser clocks of the Gravity Probe A experiment is analyzed to illustrate use of the techniques involved.

Gabriel, M.D.

1989-01-01

138

Children's Equivalence Judgments: Crossmapping Effects  

ERIC Educational Resources Information Center

Preschoolers made numerical comparisons between sets with varying degrees of shared surface similarity. When surface similarity was pitted against numerical equivalence (i.e., crossmapping), children made fewer number matches than when surface similarity was neutral (i.e, all sets contained the same objects). Only children who understood the…

Mix, Kelly S.

2008-01-01

139

Optical trapping of nanoshells  

NASA Astrophysics Data System (ADS)

We investigate near-resonant trapping of Rayleigh particles in optical tweezers. Although optical forces due to a near-resonant laser beam have been extensively studied for atoms, the situation for larger particles is that the laser wavelength is far from any absorption resonance. Theory predicts, however, that the trapping force exerted on a Rayleigh particle is enhanced, and may be three to fifty times larger for frequencies near resonance than for frequencies far off resonance. The ability to selectively trap only particles with a given absorption peak may have many practical applications. In order to investigate near-resonant trapping we are using nanoshells, particles with a dielectric core and metallic coating that can exhibit plasmon resonances. The resonances of the nanoshells can be tuned by adjusting the ratio of the radius of the dielectric core, r1, to the overall radius, r2, which includes the thickness of the metallic coating. Our nanoshells, fabricated at Rice University, consist of a silica core with a gold coating. Using back focal plane detection, we measure the trap stiffness of a single focus optical trap (optical tweezers), from a diode laser at 853 nm for nanoshells with several different r1/r2 ratios.

Hester, Brooke C.; Crawford, Alice; Kishore, Rani B.; Helmerson, Kristian; Halas, Naomi J.; Levin, Carly

2007-09-01

140

Trapping of Free Electrons in Multipole System  

NASA Astrophysics Data System (ADS)

In this paper, the effective Parameters in the confinement and trapping of fast electrons in plasma source Such as; plasma pressure, wall material of plasma chamber and magnetic mirror rate have been investigated with using Comsol & Geant4 code. The calculations are shown that the Multicusp magnetic field was effective the pressure less than 5 mTor, and the confinement effect becomes stronger with decreasing pressure. It is equivalent to a higher yield of output ions of plasma source. The number of fast electrons trapped in the magnetic field increases with increasing magnetic field intensity and using aluminum for wall material. Optimum conditions of confinement plasma, leading to increased the hot electron density, and ionization efficiency is increased. The results of investigations have demonstrated good correspondence with theoretical calculations, therefore there is the adequacy of the developed approach and the possibility to build more effective source ion on this basis.

Mahdavi, Mohammad; Khodadadi Azadboni, Fatemeh; Khodadadi Azadboni, Reza

2012-08-01

141

PACCE: Perl Algorithm to Compute Continuum and Equivalent Widths  

NASA Astrophysics Data System (ADS)

We present Perl Algorithm to Compute continuum and Equivalent Widths (pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for SSP models the equivalent widths strengths are very similar (differences <0.2A) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5A. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics.

Riffel, Rogério; Borges Vale, Tibério

2011-05-01

142

Charge Trapping in Dielectrics  

NASA Astrophysics Data System (ADS)

When a dielectric is irradiated by electrons with energy E of several kiloelectron volts, a large number of processes take place: backscattering of incident electrons, excitation and ionization of the electrons in the dielectric with binding energies lower than E, creation of excitons, radiative and nonradiative decays of the excited and ionized states, slowing down of the primary and secondary electrons, and thermalization in the conduction band. The thermalized electrons can move freely in the unoccupied conduction states of the material. If electric connection exists between the dielectric and the apparatus, then the charges normally flow out. Thermalized electrons can also be trapped in excited levels localized in the band gap of the dielectric and nonradiative and radiative recombinations from these levels can be observed. The number of the trapped electrons varies with the structural characteristics of the dielectric. In a monocrystal, this number is weak because the number of the defect states in the band gap is small, making the localization of the charges restricted. In contrast, in a polycrystal or amorphous material, the number of the trapped electrons can be large and increases with the disorder. Information on the charge effects suffered by the sample during its irradiation can be deduced by studying the trapping of electrons in localized states and, consequently, by analyzing radiations emitted from these states in the visible and X-ray ranges. In the case of oxides, F+ centers (oxygen ion vacancy having trapped one electron) and F centers (F+ center having trapped a second electron) are generally present. We will show that the F+ [leftrightarrow A: l&r arrow] F conversion can be used to study the dynamic of the trapping in the oxides. Application to various samples of crystallized and amorphous alumina will be presented.

Bonnelle, C.

2004-12-01

143

Equivalent Fractions with Word Sentences  

NSDL National Science Digital Library

Teachers can use this interactive tool to help students make sense of equivalent fractions by linking visual models to words and procedures. Students learn the value of multiplying a fraction by a fraction with a value of one. This page includes a video demonstration of the tool and sample lessons from the Conceptua curriculum. Free registration is required to use the tool. A paid subscription is necessary to access full curriculum and allow full student use.

2011-01-01

144

LED white light visual equivalence  

NASA Astrophysics Data System (ADS)

Current white LED color has a wide range of CCT and varying distance to Planckian Loci, which cause different tint in white color. This color variation keeps a number of illumination and indication applications away from LEDs. This article introduces a passive method, adding correction filters, to correct the color and achieve visual equivalence of the LED white light. Efficiency of using correction filters is discussed.

You, Chenhua

2004-10-01

145

Equivalence Checking of Reversible Circuits  

Microsoft Academic Search

Determining the equivalence of reversible circuits de- signed to meet a common specification is considered. The circuits' primary inputs and outputs must be in pure logic states but the circuits may include elementary quantum gates in addition to reversible logic gates. The specifica- tion can include don't-cares arising from constant inputs, garbage outputs, and total or partial don't-cares in the

Robert Wille; Daniel Große; D. Michael Miller; Rolf Drechsler

2009-01-01

146

Development of position-sensitive tissue equivalent proportional chamber for space dosimetry  

Microsoft Academic Search

Radiation effects on human body are evaluated using dose equivalent H, defined as the product of the absorbed dose and the quality factor given as a function of LET. In space, there exist many kinds of radiations, such as galactic cosmic rays and geomagnetic trapped particles, where charged particles and neutrons are the main components contributing to radiation dose in

S. Sasaki; K. Saito; H. Tawara; T. Nagayoshi; Y. Fujita; T. Doke; K. Terasawa; K. Miuchi; H. Matsumoto; Y. Uchihori

2007-01-01

147

Methamphetamine Interagency Task Force.  

National Technical Information Service (NTIS)

The Methamphetamine Interagency Task Force was established in 1996 in response to a provision of the Comprehensive Methamphetamine Control Act. This report represents the 2-year effort of the Task Force presenting: the principles that have guided the Task...

2000-01-01

148

Steam trap monitor  

SciTech Connect

For use in a closed steam system, apparatus coupled to a stream trap by means of a pipe and located downstream therefrom for monitoring the steam trap, the apparatus comprising: first sensing means in the pipe for determining the heat energy of a condensate flow in the pipe; second sensing means in the pipe for determining the heat energy of the condensate flow and any flow steam in the pipe; and means coupled to the first and second sensing means for determining the difference between the heat energy of the condensate flow and steam flow and the heat energy of just the condensate flow to detect the presence of any steam in the pipe in monitoring operation of the steam trap.

Ryan, M.J.

1988-08-16

149

Information leakage from logically equivalent frames  

Microsoft Academic Search

Framing effects are said to occur when equivalent frames lead to different choices. However, the equivalence in question has been incompletely conceptualized. In a new normative analysis of framing effects, we complete the conceptualization by introducing the notion of information equivalence. Information equivalence obtains when no choice-relevant inferences can be drawn from the speaker’s choice of frame. We show that,

Shlomi Sher; Craig R. M. McKenzie

2006-01-01

150

Information Leakage from Logically Equivalent Frames  

ERIC Educational Resources Information Center

Framing effects are said to occur when equivalent frames lead to different choices. However, the equivalence in question has been incompletely conceptualized. In a new normative analysis of framing effects, we complete the conceptualization by introducing the notion of information equivalence. Information equivalence obtains when no…

Sher, Shlomi; McKenzie, Craig R. M.

2006-01-01

151

Asymmetric ion trap  

DOEpatents

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

Barlow, Stephan E. (Richland, WA); Alexander, Michael L. (Richland, WA); Follansbee, James C. (Pasco, WA)

1997-01-01

152

Low interfacial trap density and sub-nm equivalent oxide thickness in In{sub 0.53}Ga{sub 0.47}As (001) metal-oxide-semiconductor devices using molecular beam deposited HfO{sub 2}/Al{sub 2}O{sub 3} as gate dielectrics  

SciTech Connect

We investigated the passivation of In{sub 0.53}Ga{sub 0.47}As (001) surface by molecular beam epitaxy techniques. After growth of strained In{sub 0.53}Ga{sub 0.47}As on InP (001) substrate, HfO{sub 2}/Al{sub 2}O{sub 3} high-{kappa} oxide stacks have been deposited in-situ after surface reconstruction engineering. Excellent capacitance-voltage characteristics have been demonstrated along with low gate leakage currents. The interfacial density of states (D{sub it}) of the Al{sub 2}O{sub 3}/In{sub 0.53}Ga{sub 0.47}As interface have been revealed by conductance measurement, indicating a downward D{sub it} profile from the energy close to the valence band (medium 10{sup 12} cm{sup -2}eV{sup -1}) towards that close to the conduction band (10{sup 11} cm{sup -2}eV{sup -1}). The low D{sub it}'s are in good agreement with the high Fermi-level movement efficiency of greater than 80%. Moreover, excellent scalability of the HfO{sub 2} has been demonstrated as evidenced by the good dependence of capacitance oxide thickness on the HfO{sub 2} thickness (dielectric constant of HfO{sub 2}{approx}20) and the remained low D{sub it}'s due to the thin Al{sub 2}O{sub 3} passivation layer. The sample with HfO{sub 2} (3.4 nm)/Al{sub 2}O{sub 3} (1.2 nm) as the gate dielectrics has exhibited an equivalent oxide thickness of {approx}0.93 nm.

Chu, L. K. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Katholieke Universiteit Leuven, 3001 Leuven (Belgium); Merckling, C.; Dekoster, J.; Caymax, M. [Interuniversity Microelectronics Center (IMEC vzw), 3001 Leuven (Belgium); Alian, A.; Heyns, M. [Katholieke Universiteit Leuven, 3001 Leuven (Belgium); Interuniversity Microelectronics Center (IMEC vzw), 3001 Leuven (Belgium); Kwo, J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Hong, M. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

2011-07-25

153

[Lscr]0-equivalence of maps  

NASA Astrophysics Data System (ADS)

We use the theory of the integral closure of an ideal to study the equivalence of map-germs under C0 coordinate changes in the target. We also derive a formula for the number of double points of a map germ from Cn [rightward arrow] C2n in terms of the Segre number of dimension 0 of an ideal associated to the double point locus of f, and the number of Whitney umbrellas of the composition of f with a generic projection to C2n[minus sign]1.

Gaffney, Terence

2000-05-01

154

Equivalent circuit for aperture antennas  

NASA Astrophysics Data System (ADS)

The commonly used equivalent circuit based on a constant-voltage generator does not correctly characterize scattering by an aperture antenna, nor does its dual, the constant-current generator. This long-standing dilemma has been resolved by combining voltage and current sources to form a constant-power source. The power generated by this source is equated to the available power in a plane wave incident on the aperture. The voltage and current of the two sources and their respective internal impedances are then completely determined from the aperture area, the impedance, the aperture efficiency, and the relative power pattern of the antenna.

Love, A. W.

1987-06-01

155

The elliptical Penning trap  

NASA Astrophysics Data System (ADS)

The application of an additional azimuthal quadrupolar electrostatic field to a Penning trap leads to a field configuration referred to as an elliptical Penning trap. The resulting changes of the radial ion motions have been investigated experimentally and by use of simulations. The eigenfrequencies, i.e., the magnetron frequency and the reduced cyclotron frequency , are found to be shifted with respect to those of the standard Penning trap [omega]-, [omega]+, respectively. As the shift of the magnetron frequency is larger than that of the reduced cyclotron frequency their sum is also a function of the ellipticity and no longer equal to the cyclotron frequency in the absence of an electric trapping field [omega]cDqB/m. The frequency shifts were investigated for argon and fullerene ions. The experimental studies were performed by time-of-flight (ToF) analysis of the ion cyclotron resonance and by Fourier-transform ion-cyclotron-resonance mass spectrometry (FT-ICR MS). The experimental and simulated values are in agreement with theoretical predictions [M. Kretzschmar, this issue] when the influence of higher multipole terms is taken into account.

Breitenfeldt, Martin; Baruah, Sudarshan; Blaum, Klaus; Herlert, Alexander; Kretzschmar, Martin; Martinez, Franklin; Marx, Gerrit; Schweikhard, Lutz; Walsh, Noelle

2008-08-01

156

Practical axial optical trapping  

PubMed Central

We describe a new method for calibrating optical trapping measurements in which tension is applied in the direction of the laser beam to a molecule tethered between a surface and an optically trapped bead. Specifically, we present a generally-applicable procedure for converting from the measured scattering intensity and the measured stage displacement to applied tension and bead-coverslip separation, using measurements of the light intensity scattered from an untethered, trapped bead. Our calibration accounts for a number of effects, including aberrations and the interference of forward-reflected bead-scattered light with the trapping beam. To demonstrate the accuracy of our method, we show measurements of the DNA force-versus-extension relation using a range of laser intensities, and show that these measurements match the expected extensible wormlike-chain (WLC) behavior. Finally, we also demonstrate a force-clamp, in which the tension in a tether is held fixed while the extension varies as a result of molecular events.

Mack, A. H.; Schlingman, D. J.; Regan, L.; Mochrie, S. G. J.

2012-01-01

157

Paul Trap Simulator Experiment  

NASA Astrophysics Data System (ADS)

The Paul Trap Simulator Experiment (PTSX) is a compact laboratory facility whose purpose is to simulate the nonlinear dynamics of intense charged particle beam propagation over a large distance through an alternating-gradient transport system. The simulation is possible because the quadrupole electric fields of the cylindrical Paul trap exert radial forces on the charged particles that are analogous to the radial forces that a periodic focusing quadrupole magnetic field exert on the beam particles in the beam frame. By controlling the waveform applied to the walls of the trap, PTSX will explore physics issues such as beam mismatch, envelope instabilities, halo particle production, compression techniques, collective wave excitations, and beam profile effects. Initial experiments have concentrated on characterizing the cesium ion source and studying ``free-steaming" ions that travel directly from the ion source to the Faraday cup diagnostic. The aluminosilicate cesium source provides up to 30 ?A, which is greater than the estimated 300 pA required to load the trap to a density of 10^6 cm-3. Variation of the wall voltage and the oscillation frequency reveals the stability limit of the single particle orbits.

Gilson, Erik P.; Davidson, Ronald C.; Efthimion, Philip C.; Majeski, Richard

2002-11-01

158

Thermostatic steam trap  

Microsoft Academic Search

A thermostatic trap is described for a heating system having a feed pipe connected to a source of steam and a discharge pipe for discharge of condensate and comprising: housing means defining a volume and comprising a bowl shaped body, a removable cover therefor, a housing inlet pipe portion projecting from a side wall portion of the body and adapted

A. H. Anderson; A. E. Mac Nicol

1987-01-01

159

The Universal Trap.  

ERIC Educational Resources Information Center

The compulsory system of education is criticized on the grounds that it has become a regimented "universal trap" antithetical to democracy. In contrast to the Jeffersonian concept of education in the service of citizen initiative for the preservation of freedom, current compulsory education is a tool of industrialism and of a rigidly stratified…

Goodman, Paul

160

Filter vapor trap  

Microsoft Academic Search

A sintered filter trap is adapted for insertion in a gas stream of sodium vapor to condense and deposit sodium thereon. The filter is heated and operated above the melting temperature of sodium, resulting in a more efficient means to remove sodium particulates from the effluent inert gas emanating from the surface of a liquid sodium pool. Preferably the filter

Guon; Jerold

1976-01-01

161

Practical axial optical trapping  

NASA Astrophysics Data System (ADS)

We describe a new method for calibrating optical trapping measurements in which tension is applied in the direction of the laser beam to a molecule tethered between a surface and an optically trapped bead. Specifically, we present a generally-applicable procedure for converting from the measured scattering intensity and the measured stage displacement to applied tension and bead-coverslip separation, using measurements of the light intensity scattered from an untethered, trapped bead. Our calibration accounts for a number of effects, including aberrations and the interference of forward-reflected bead-scattered light with the trapping beam. To demonstrate the accuracy of our method, we show measurements of the DNA force-versus-extension relation using a range of laser intensities, and show that these measurements match the expected extensible wormlike-chain (WLC) behavior. Finally, we also demonstrate a force-clamp, in which the tension in a tether is held fixed while the extension varies as a result of molecular events.

Mack, A. H.; Schlingman, D. J.; Regan, L.; Mochrie, S. G. J.

2012-10-01

162

Entanglement of Trapped Ions  

NASA Astrophysics Data System (ADS)

Entanglement, its generation, manipulation, measurement and fundamental understanding is at the very heart of quantum mechanics. We here report on the creation and characterization of entangled states of up to 8 trapped ions, the investigation of long-lived two-ion Bell-states and on experiments towards entangling ions and photons.

Becher, C.; Benhelm, J.; Chek-Al-Kar, D.; Chwalla, M.; Dür, W.; Gühne, O.; Häffner, H.; Hänsel, W.; Körber, T.; Kreuter, A.; Lancaster, G. P. T.; Monz, T.; Phillips, E. S.; Rapol, U. D.; Riebe, M.; Roos, C. F.; Russo, C.; Schmidt-Kaler, F.; Blatt, R.

2005-12-01

163

The Universal Trap.  

ERIC Educational Resources Information Center

|The compulsory system of education is criticized on the grounds that it has become a regimented "universal trap" antithetical to democracy. In contrast to the Jeffersonian concept of education in the service of citizen initiative for the preservation of freedom, current compulsory education is a tool of industrialism and of a rigidly stratified…

Goodman, Paul

164

Contextual control of emergent equivalence relations.  

PubMed Central

Three college students in Experiment 1 and 1 student in Experiment 2 learned visual conditional discriminations under contextual control by tones; the visual comparison stimulus that was correct with a given sample stimulus depended on whether a high tone or a low tone was present. Two of the subjects in Experiment 1 then demonstrated the emergence of two sets of contextually controlled three-member classes of equivalent stimuli, and the subject in Experiment 2 showed the emergence of contextually controlled four-member classes; the class membership of each stimulus varied as a function of the tones. Class membership was demonstrated by the subjects' performance of new conditional discriminations that they had never been taught directly. In Experiment 2, the procedures were intended to ensure that the tones exerted second-order conditional control and did not simply form compounds with each of the visual stimuli, but the subject's verbal description of the tasks suggested that this intention might not have been successful. It could not be ascertained, therefore, whether the tones exerted contextual control as independent second-order conditional stimuli or simply as common elements of auditory-visual stimulus compounds.

Bush, K M; Sidman, M; de Rose, T

1989-01-01

165

Biomonitoring equivalents for inorganic arsenic.  

PubMed

This paper presents Biomonitoring Equivalents (BEs) for inorganic arsenic. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline, and are derived by integrating available data on pharmacokinetics with existing chemical risk assessments. This study reviews available health-based exposure guidance values for arsenic based on recent evaluations from the United States Environmental Protection Agency (US EPA), US Agency for Toxic Substances and Disease Registry (ATSDR) and Health Canada (HC). BE values corresponding to the Reference Dose (RfD) or risk-specific doses for cancer endpoints from these agencies were derived based on kinetic data (urinary excretion) from controlled dosing studies in humans. The BE values presented here provide estimates of the sum of inorganic arsenic-derived urinary biomarkers (inorganic arsenic, monomethylated arsenic, and dimethylated arsenic). The BE associated with the United States Environmental Protection Agency's Reference Dose and the Agency for Toxic Substances and Disease Registry's Minimal Risk Level is 6.4 microg arsenic/L urine. The BEs associated with the various cancer risk assessments are significantly lower. These BE values may be used as screening tools for evaluation of biomonitoring data for inorganic arsenic in a public health risk context. PMID:20547195

Hays, Sean M; Aylward, Lesa L; Gagné, Michelle; Nong, Andy; Krishnan, Kannan

2010-06-12

166

Electrostatic traps for dipolar excitons  

Microsoft Academic Search

We consider the design of two-dimensional electrostatic traps for dipolar indirect excitons. We show that the exciton dipole-dipole interaction, combined with the in-plane electric fields that arise due to the trap geometry, constrains the maximal density and lifetime of trapped excitons. We derive an analytic estimate of these values and determine their dependence on the trap geometry, thus suggesting the

Ronen Rapaport; Gang Chen; Steven Simon; Oleg Mitrofanov; Loren Pfeiffer; P. M. Platzman

2005-01-01

167

Trapping atoms with optical potentials  

NASA Astrophysics Data System (ADS)

Ultralow temperatures produced with polarization-gradient cooling now allow atoms to be trapped in shallow optical potential wells. We present evidence for the quantized motion of atoms in a 1-D optical molasses with the observation of spontaneous Raman transitions between vibrational levels in these wells, observed in fluorescence. In addition, we discuss the features of a far off resonance trap (FORT) -- a single focus dipole force trap so far off resonance to be an essentially ground-state trap.

Rolston, Steven L.; Gerz, Christoph; Helmerson, Kristian; Jessen, P. S.; Lett, Paul D.; Phillips, William D.; Spreeuw, R. J.; Westbrook, C. I.

1992-10-01

168

Indirect excitons in elevated traps.  

PubMed

We report on the study of indirect excitons in elevated traps. The transition from a normal to elevated trap results in the appearance of narrow lines in the emission spectrum. The density, temperature, and voltage dependences indicate that these lines correspond to the emission of individual states of indirect excitons in a disorder potential in the elevated trap. PMID:19382780

High, A A; Hammack, A T; Butov, L V; Mouchliadis, L; Ivanov, A L; Hanson, M; Gossard, A C

2009-05-01

169

Nondestructive evaluation of steam traps  

NASA Astrophysics Data System (ADS)

Many thermographers have touted infrared thermography as an effective maintenance tool for evaluating steam traps for years. However, several investigators have raised questions about thermal measurement's effectiveness in this application. This paper explores and compares infrared thermography and ultrasonic detection methods for steam trap testing and provides guidelines for a successful trap survey.

Orlove, Gary L.

1999-03-01

170

Steam traps: simple but important  

Microsoft Academic Search

An overeview of various steam trap designs and their characteristics is presented. The basic uses of each design are discussed. The need for steam traps is reviewed and it is stressed that steam traps (which do not require operator attendance) is the simplest and most cost effective means of allowing condensate to drain away from critical areas. The four basic

Hammond

1981-01-01

171

Steam-trap users guide  

Microsoft Academic Search

Steam traps are an important element in the efficient operation of a steam system and in energy conservation. The high cost of producing and delivering steam mandates an effective steam-trap inspection and maintenance program at all applicable naval activities. A comprehensive program for steam-trap inspection and maintenance will pay for itself many times over in the cost of steam that

J. C. King; D. M. Sneed

1985-01-01

172

Nondestructive evaluation of steam traps  

Microsoft Academic Search

Many thermographers have touted infrared thermography as an effective maintenance tool for evaluating steam traps for years. However, several investigators have raised questions about thermal measurement's effectiveness in this application. This paper explores and compares infrared thermography and ultrasonic detection methods for steam trap testing and provides guidelines for a successful trap survey.

Gary L. Orlove

1999-01-01

173

Foreword: Biomonitoring Equivalents special issue.  

PubMed

The challenge of interpreting results of biomonitoring for environmental chemicals in humans is highlighted in this Foreword to the Biomonitoring Equivalents (BEs) special issue of Regulatory Toxicology and Pharmacology. There is a pressing need to develop risk-based tools in order to empower scientists and health professionals to interpret and communicate the significance of human biomonitoring data. The BE approach, which integrates dosimetry and risk assessment methods, represents an important advancement on the path toward achieving this objective. The articles in this issue, developed as a result of an expert panel meeting, present guidelines for derivation of BEs, guidelines for communication using BEs and several case studies illustrating application of the BE approach for specific substances. PMID:18395953

Meek, M E; Sonawane, B; Becker, R A

2008-03-06

174

When Is a Task a Task?  

ERIC Educational Resources Information Center

|Over the past decade, vocational and technical education teachers were encouraged to use commercially produced task lists to develop their curriculum materials. Unfortunately, however, many commercially developed task lists distributed by private companies, state departments of education, universities, and many other agencies may, to some extent,…

Duenk, Lester G.

175

Matched Filtering of Equivalent-Time Signals.  

National Technical Information Service (NTIS)

Equivalent-time signal acquisition in the presence of stationary additive noise is contrasted with real time transient recording. It is shown how the substantial noise decorrelation encountered with equivalent time methods can markedly influence the form ...

J. J. Oreilly

1981-01-01

176

21 CFR 26.6 - Equivalence assessment.  

Code of Federal Regulations, 2010 CFR

...false Equivalence assessment. 26.6 Section...GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL...Good Manufacturing Practices § 26.6 Equivalence assessment. (a) The...draft programs for assessing the...

2010-04-01

177

21 CFR 26.6 - Equivalence assessment.  

Code of Federal Regulations, 2010 CFR

...false Equivalence assessment. 26.6 Section...GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL...Good Manufacturing Practices § 26.6 Equivalence assessment. (a) The...draft programs for assessing the...

2009-04-01

178

49 CFR 38.2 - Equivalent facilitation.  

Code of Federal Regulations, 2012 CFR

...Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent...

2012-10-01

179

Criteria equivalent to the Riemann Hypothesis  

NASA Astrophysics Data System (ADS)

We give a brief overview of a few criteria equivalent to the Riemann Hypothesis. Next we concentrate on the Riesz and Báez-Duarte criteria. We prove that they are equivalent and we provide some computer data to support them.

Cis?o, J.; Wolf, M.

2008-11-01

180

Power System Dynamic Equivalents Using Identification Techniques.  

National Technical Information Service (NTIS)

This report describes the development and demonstration of an equivalent mathematical model for the representation of the external system dynamics at the boundary buses of an internal system. These equivalents are needed for different system studies in wh...

M. A. H. Ibrahim

1976-01-01

181

46 CFR 169.109 - Equivalents.  

Code of Federal Regulations, 2012 CFR

...Equivalents. 169.109 Section 169.109 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General Provisions § 169.109 Equivalents. Substitutes for a fitting,...

2012-10-01

182

Trapped Miner Communication  

Microsoft Academic Search

\\u000a Accident due to roof fall and collapse of side gallery is a regular occurrence in underground coal mines which causes death\\u000a of huge number of miners. To save valuable miners’ life, a suitable system is required for detecting the precise location\\u000a of a trapped miner and helping the rescue team or mine management in displacing the debris from the right

L. K. Bandyopadhyay; S. K. Chaulya; P. K. Mishra

183

Trapped and excited  

SciTech Connect

The trapped w modes of stars with a first order phase transition (a density discontinuity) are computed and the excitation of some of the modes of these stars by a perturbing shell is investigated. Attention is restricted to odd parity (''axial'') w modes. With R the radius of the star, M its mass, R{sub i} the radius of the inner core and M{sub I} the mass of such core, it is shown that stars with R/M{ge}5 can have several trapped w modes, as long as R{sub i}/M{sub i}{lt}2.6. Excitation of the least damped w mode is confirmed for a few models. All of these stars can only exist, however, for values of the ratio between the densities of the two phases, greater than {approximately}46. We also show that stars with a phase transition and a given value of R/M can have far more trapped modes than a homogeneous single density star with the same value of R/M, provided both R/M and R{sub i}/M{sub i} are smaller than 3. If the phase transition is very fast, most of the stars with trapped modes are unstable to radial oscillations. We compute the time of instability, and find it to be comparable to the damping of the w mode excited in most cases where w-mode excitation is likely. If on the other hand the phase transition is slow, all the stars are stable to radial oscillations.

Andrade, Zeferino

2001-06-15

184

Filter vapor trap  

DOEpatents

A sintered filter trap is adapted for insertion in a gas stream of sodium vapor to condense and deposit sodium thereon. The filter is heated and operated above the melting temperature of sodium, resulting in a more efficient means to remove sodium particulates from the effluent inert gas emanating from the surface of a liquid sodium pool. Preferably the filter leaves are precoated with a natrophobic coating such as tetracosane.

Guon, Jerold (Canoga Park, CA)

1976-04-13

185

Transport quantum logic gates for trapped ions  

SciTech Connect

Many efforts are currently underway to build a device capable of large scale quantum information processing (QIP). Whereas QIP has been demonstrated for a few qubits in several systems, many technical difficulties must be overcome in order to construct a large-scale device. In one proposal for large-scale QIP, trapped ions are manipulated by precisely controlled light pulses and moved through and stored in multizone trap arrays. The technical overhead necessary to precisely control both the ion geometrical configurations and the laser interactions is demanding. Here we propose methods that significantly reduce the overhead on laser-beam control for performing single- and multiple-qubit operations on trapped ions. We show how a universal set of operations can be implemented by controlled transport of ions through stationary laser beams. At the same time, each laser beam can be used to perform many operations in parallel, potentially reducing the total laser power necessary to carry out QIP tasks. The overall setup necessary for implementing transport gates is simpler than for gates executed on stationary ions. We also suggest a transport-based two-qubit gate scheme utilizing microfabricated permanent magnets that can be executed without laser light.

Leibfried, D.; Knill, E.; Ospelkaus, C.; Wineland, D. J. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

2007-09-15

186

Efficient Sympathetic Cooling of Trapped Atomic Ions  

NASA Astrophysics Data System (ADS)

A challenge of performing ion trap quantum computation with chains of ions is the heating of the trap vibrational modes. Trap heating can result in unwanted occupation of vibrational modes and a reduced fidelity for two ion gates. To combat this, specific ions within the chain can be tasked with cooling the entire chain via sympathetic cooling. The strength of the interaction between the cooling laser and cooling ions may have a significant effect on how efficiently the chain is sympathetically cooled. This interaction can be controlled via the intensity and detuning of the cooling beam as well as the time the cooling ions spend interacting with the cooling laser versus thermalizing with the ion chain. By using separate isotopes of Ca+, we can construct a chain of cooling and information ions with each isotope interacting with its resonant cooling laser independently. By adjusting the aforementioned interaction parameters and measuring the sideband spectrum of the information ions, we will be able to find the most efficient sympathetic cooling parameters. We will describe the experimental results so far as well as future related investigations.

Vittorini, Grahame; Clark, Craig; Brown, Kenneth

2011-06-01

187

STABLE EQUIVALENCES RELATED WITH SYZYGY FUNCTORS  

Microsoft Academic Search

Let :m od? ? ? mod?? be a stable equivalence betweennite dimensional self-injective algebras over aeld. Then preserves triangles in the triangulated category modif and only if commutes with syzygy functors. As an application, we study some stable equivalence induced by socle equivalence. Throughout this paper K will be axedeld, and all algebras will be basicnite dimensional self-injective K-algebras without

YOSUKE OHNUKI

188

Magnetic trap for thulium atoms  

SciTech Connect

For the first time ultra-cold thulium atoms were trapped in a magnetic quadrupole trap with a small field gradient (20 Gs cm{sup -1}). The atoms were loaded from a cloud containing 4x10{sup 5} atoms that were preliminarily cooled in a magneto-optical trap to the sub-Doppler temperature of 80 {mu}K. As many as 4x10{sup 4} atoms were trapped in the magnetic trap at the temperature of 40 {mu}K. By the character of trap population decay the lifetime of atoms was determined (0.5 s) and an upper estimate was obtained for the rate constant of inelastic binary collisions for spin-polarised thulium atoms in the ground state (g{sub in} < 10{sup -11}cm{sup 3} s{sup -1}). (magnetic traps)

Sukachev, D D; Sokolov, A V; Chebakov, K A; Akimov, A V; Kolachevskii, N N; Sorokin, Vadim N [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2011-08-31

189

Stimulus Equivalence, Generalization, and Contextual Stimulus Control in Verbal Classes  

PubMed Central

Stimulus generalization and contextual control affect the development of equivalence classes. Experiment 1 demonstrated primary stimulus generalization from the members of trained equivalence classes. Adults were taught to match six spoken Icelandic nouns and corresponding printed words and pictures to one another in computerized three-choice matching-to-sample tasks. Tests confirmed that six equivalence classes had formed. Without further training, plural forms of the stimuli were presented in tests for all matching performances. All participants demonstrated virtually errorless performances. In Experiment 2, classifications of the nouns used in Experiment 1 were brought under contextual control. Three nouns were feminine and three were masculine. The match-to-sample training taught participants to select a comparison of the same number as the sample (i.e., singular or plural) in the presence of contextual stimulus A regardless of noun gender. Concurrently, in the presence of contextual stimulus B, participants were taught to select a comparison of the same gender as the sample (i.e., feminine or masculine), regardless of number. Generalization was assessed using a card-sorting test. All participants eventually sorted the cards correctly into gender and number stimulus classes. When printed words used in training were replaced by their picture equivalents, participants demonstrated almost errorless performances.

Sigur?ardottir, Zuilma Gabriela; Mackay, Harry A; Green, Gina

2012-01-01

190

Equivalent-circuit model for vacuum ultraviolet irradiation of dielectric films  

SciTech Connect

Vacuum ultraviolet (VUV) irradiation, which occurs during plasma processing, causes photoemission of electrons from the dielectrics. Photoemission primarily occurs from defect states in the band gap of the dielectric and results in trapped positive charges. The trapped positive charges are negated by photoinjection of electrons from the underlying substrate into the dielectric. The authors propose an equivalent-circuit model using with which, once the circuit parameters are determined, charging of dielectric materials under VUV irradiation can be predicted. The circuit includes a dielectric capacitor, the intrinsic and photo conductivities of the dielectric and substrate, and the processes of photoemission and photoinjection.

Sinha, Harsh; Shohet, J. Leon [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2012-05-15

191

A Self-Organizing Neural Model of Motor Equivalent Reaching and Tool Use by a Multijoint Arm  

Microsoft Academic Search

This paper describes a self-organizing neural model for eye-hand coordination. Called the DIRECT model, it embodies a solution of the classical motor equivalence problem. Motor equivalence computations allow humans and other animals to flexibly employ an arm with more degrees of freedom than the space in which it moves to carry out spatially defined tasks under conditions that may require

Daniel Bullock; Stephen Grossberg; Frank H. Guenther

1993-01-01

192

Dietary Supplements Task Force.  

National Technical Information Service (NTIS)

The Dietary Supplements Task Force was charged with examining the issues regarding dietary supplements and developing a regulatory framework for these products. To facilitate the orderly development of regulatory strategies, the Task Force divided the uni...

1992-01-01

193

Persistence of motor-equivalent postural fluctuations during bipedal quiet standing.  

PubMed

Theoretical and empirical work indicates that the central nervous system is able to stabilize motor performance by selectively suppressing task-relevant variability (TRV), while allowing task-equivalent variability (TEV) to occur. During unperturbed bipedal standing, it has previously been observed that, for task variables such as the whole-body center of mass (CoM), TEV exceeds TRV in amplitude. However, selective control (and correction) of TRV should also lead to different temporal characteristics, with TEV exhibiting higher temporal persistence compared to TRV. The present study was specifically designed to test this prediction. Kinematics of prolonged quiet standing (5 minutes) was measured in fourteen healthy young participants, with eyes closed. Using the uncontrolled manifold analysis, postural variability in six sagittal joint angles was decomposed into TEV and TRV with respect to four task variables: (1) center of mass (CoM) position, (2) head position, (3) trunk orientation and (4) head orientation. Persistence of fluctuations within the two variability components was quantified by the time-lagged auto-correlation, with eight time lags between 1 and 128 seconds. The pattern of results differed between task variables. For three of the four task variables (CoM position, head position, trunk orientation), TEV significantly exceeded TRV over the entire 300 s-period.The autocorrelation analysis confirmed our main hypothesis for CoM position and head position: at intermediate and longer time delays, TEV exhibited higher persistence than TRV. Trunk orientation showed a similar trend, while head orientation did not show a systematic difference between TEV and TRV persistence. The combination of temporal and task-equivalent analyses in the present study allow a refined characterization of the dynamic control processes underlying the stabilization of upright standing. The results confirm the prediction, derived from computational motor control, that task-equivalent fluctuations for specific task variables show higher temporal persistence compared to task-relevant fluctuations. PMID:23110228

Verrel, Julius; Pradon, Didier; Vuillerme, Nicolas

2012-10-26

194

Development of a Compact Plasma Trap for Experimental Beam Physics  

Microsoft Academic Search

A tabletop experimental system has been developed for the study of various collective effects in space-charge-dominated beams. It is based on the recently proposed idea that the dynamic motion of a one-component plasma in a trap can be made physically equivalent to that of a charged-particle beam propagating through a linear transport channel. In this paper, we report on the

Ryota Takai; Hayato Enokizono; Kiyokazu Ito; Yasuhiko Mizuno; Kota Okabe; Hiromi Okamoto

2006-01-01

195

Personalised Task Representation.  

National Technical Information Service (NTIS)

Personalised Task Representation is a system of task analysis that is being developed at AMTE/APU. A worked example of the current PTR system is demonstrated and its rationale and relationship to the more traditional forms of task analysis are discussed. ...

R. Gregory

1979-01-01

196

Patinformatics: Tasks to tools  

Microsoft Academic Search

This article starts with an overview of the field of patinformatics––the science of analyzing patent information to discover relationships and trends. This is followed by a survey of many common analysis tasks in this field, and many of the software tools available to tackle these tasks. The survey is set out under the tasks of list cleanup and grouping of

Anthony J. Trippe

2003-01-01

197

Trapped Ion Frequency Standards  

NASA Astrophysics Data System (ADS)

Trapped ions form the basis for a high performance frequency standard since long interrogation times are possible in a nearly perturbation free environment. At JPL, approximately 2x10^6 ^199Hg+ ions are confined in a Linear Ion Trap (LIT)(J.D. Prestage, G.J. Dick, L. Maleki, J.Appl. Phys. 66, 1013 (1989).) and cooled to near room temperature by collisions with a helium buffer gas. Atomic state selection is accomplished by optical pumping using 194 nm light from a ^202Hg lamp and the 40.5 GHz ground state hyperfine transition is interrogated using Ramsey successive oscillatory fields. With an interrogation time of 8 seconds, the measured fractional frequency stability is ?_y(?)=6.5x10-14/ ?^1/2, where ? is the averaging interval in seconds. The frequency stability measured between two Hg^+ ion standards currently exceeds other standards between 10,000 seconds and 1 month. (R.L. Tjoelker, J.D. Prestage, L. Maleki, in Symp. on Freq. Standards & Metrology, Woods Hole MA,(1995).) The long term differential drift between an ion standard and a cavity tuned hydrogen maser over a 5 month interval was measured to be (2.1± 0.8)x10-16/day. A new two segment linear ion trap currently under development separates the ion loading and atomic state selection region from the microwave interrogation region. Initial measurements indicate a stability of ?_y(?)=5.6x10-14/ ?^1/2. Operating at reduced linear ion densities, this configuration should allow for improved accuracy and long term stability.

Tjoelker, R. L.

1996-03-01

198

Atom trap trace analysis  

SciTech Connect

A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.

Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O'Connor, T. P.; Young, L.

2000-05-25

199

It Pays to Be Organized: Organizing Arithmetic Practice around Equivalent Values Facilitates Understanding of Math Equivalence  

ERIC Educational Resources Information Center

|This experiment tested the hypothesis that organizing arithmetic fact practice by equivalent values facilitates children's understanding of math equivalence. Children (M age = 8 years 6 months, N = 104) were randomly assigned to 1 of 3 practice conditions: (a) equivalent values, in which problems were grouped by equivalent sums (e.g., 3 + 4 = 7,…

McNeil, Nicole M.; Chesney, Dana L.; Matthews, Percival G.; Fyfe, Emily R.; Petersen, Lori A.; Dunwiddie, April E.; Wheeler, Mary C.

2012-01-01

200

Steam-trap users guide  

SciTech Connect

Steam traps are an important element in the efficient operation of a steam system and in energy conservation. The high cost of producing and delivering steam mandates an effective steam-trap inspection and maintenance program at all applicable naval activities. A comprehensive program for steam-trap inspection and maintenance will pay for itself many times over in the cost of steam that would likewise be wasted by neglected traps. This Guide provides the basics in steam-trap operation, selection and installation, inspection and troubleshooting, and repair and testing. Most important, though, it provides guidance and practical assistance in establishing an inspection and maintenance program. Implementation of such a program for steam traps would be a significant step in energy conservation and better use of utility operation funds. The Users Guide is useful as a handbook for individual study or for group training.

King, J.C.; Sneed, D.M.

1985-04-01

201

Spectroscopy of trapped francium  

NASA Astrophysics Data System (ADS)

Atomic francium, which has no stable isotopes, is an attractive candidate for measurements of parity non-conservation. A heavy ion fusion reaction produces Fr at the Stony Brook superconducting LINAC, and we confine about 10,000 atoms in a magneto-optical trap (MOT). We made precise measurements (300 ppm) of the hyperfine splitting of the 7P1/2 state. Combining these measurements with previous measurements of the ground state hyperfine splitting, enabled us to extract the hyperfine anomaly in these states, and thus probe the nuclear magnetization. We located the previously unobserved 7D states and measured their energies and hyperfine splittings. Using time-correlated single-photon counting, we measured radiative lifetimes of 73.6 +/- 0.3 ns for the 7D3/2 level and 67.7 +/- 2.9 ns for the 7D5/2 level. We have constructed a new apparatus for efficient trapping of Fr in preparation for a measurement of the nuclear anapole moment.

Grossman, Joshua Matus

202

Radio-frequency quadrupole trap as a tool for experimental beam physics  

Microsoft Academic Search

In recent papers [Okamoto, Hiroshima University Preprint HUBP-01\\/98 (1998); Okamoto and Tanaka, Nucl. Instr. Meth. A 437 (1999) 178], we proposed a novel experimental approach to investigate various collective effects in space-charge-dominated beams. It was demonstrated that either a radio-frequency quadrupole trap or a solenoidal trap could reproduce non-linear processes equivalent to those in a beam transport channel. In the

Hiromi Okamoto; Yoshio Wada; Ryota Takai

2002-01-01

203

Comment on 'Quantum time-of-flight distribution for cold trapped atoms'  

SciTech Connect

Ali et al. [Phys. Rev. A 75, 042110 (2007)] have claimed that empirically testable differences exist between the quantum and semiclassical time of flight distribution for cold trapped atoms. We believe these claims to be misleading. For the particular case of noninteracting bosonic particles released from a harmonic trapping potential, we show that the quantum and semiclassical calculations for the time-of-flight distribution are equivalent, provided one is not too close to the quantum degeneracy point.

Gomes, J. Viana; Belsley, M. [Departamento de Fisica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Boiron, D. [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS, Univ Paris-Sud, Campus Polytechnique, RD128, 91127 Palaiseau cedex (France)

2008-02-15

204

Optical traps with geometric aberrations  

SciTech Connect

We assess the influence of geometric aberrations on the in-plane performance of optical traps by studying the dynamics of trapped colloidal spheres in deliberately distorted holographic optical tweezers. The lateral stiffness of the traps turns out to be insensitive to moderate amounts of coma, astigmatism, and spherical aberration. Moreover holographic aberration correction enables us to compensate inherent shortcomings in the optical train, thereby adaptively improving its performance. We also demonstrate the effects of geometric aberrations on the intensity profiles of optical vortices, whose readily measured deformations suggest a method for rapidly estimating and correcting geometric aberrations in holographic trapping systems.

Roichman, Yael; Waldron, Alex; Gardel, Emily; Grier, David G

2006-05-20

205

DNA Separation Using Photoelectrophoretic Traps  

SciTech Connect

In our recent publications we presented a design that allows formation of highly localized and optically controlled electrophoretic traps. 1,2 We demonstrated that electrophoretic traps can be utilized for biomolecule photoconcentration, optically directed transport, and separation by size. 1,2 In the current publication we suggest a hybrid design for biomolecule separation which implements electrophoretic traps in tandem with well-established electrophoretic techniques. We perform Monte Carlo simulations that demonstrate that the resolution of well-established electrophoretic techniques can be greatly enhanced by introducing photoelectrophoretic traps.

Braiman, Avital [ORNL; Thundat, Thomas George [ORNL; Rudakov, Fedor M [ORNL

2011-01-01

206

Black Hole Optical Dipole Trap  

NASA Astrophysics Data System (ADS)

One of the major constraints for obtaining high densities in magneto-optical traps (MOT) and optical dipole traps is the heating of the trapped atoms by scattered photons. In the magneto-optical trap, scattering can be significantly reduced, and densities increased by using the dark MOT technique to shield the trapped atoms from the repumping laser, allowing higher densities to be realized. While the dark MOT allows a density increase of a almost an order of magnitude, scattered repumping light still plays an important role in the maximum achievable density. We demonstrate a new black hole optical trap technique using cesium. The black hole optical trap uses a Ti:Saph laser, tuned to 876 nm (6P1/2 - 6D3/2 of Cs), to confine the atoms in the standard far off-resonance trap (FORT) configuration while simultaneously Stark shifting the D1 repumping transition far off resonance. This has several advantages over the standard FORT technique. Since atoms are dark to the repumping transition, heating due to scattering is significantly reduced. Collisional losses due to atoms in different hyperfine ground states is significantly reduced since virtually all of the trapped atoms fall into the F=3 ground state. In addition, the FORT can be continuously loaded from the MOT without the need for transient loading steps.

Brooke, G.; Takekoshi, T.; Patterson, B. M.; Knize, R. J.

2004-05-01

207

Equivalent linearization of a squeeze film damper  

SciTech Connect

The equivalent linearization of an intershaft squeeze film damper in a two shaft engine system is investigated. The two shaft centers at the damper position are assumed to move in different elliptical offset orbits and at synchronous frequency with the unbalanced rotor (e.g., the high pressure rotor). The nonlinear damper force is resolved into two orthogonal components along the absolute coordinate directions and, in turn, each of these force components is supposed to be equivalent to the sum of an average force, a linear spring force, and a linear damping force in the corresponding direction. By using the method of equivalent linearization by harmonic balance, the six parameters of the equivalent forces, including two average forces, two equivalent spring coefficients, and two equivalent damping coefficients, are expressed analytically by the squeeze film forces and the assumed orbital motion of the two shaft centers at the damper position. 10 references.

Chen, S.; Liu, S.

1986-10-01

208

The equivalent fundamental-mode source  

Microsoft Academic Search

In this work, we describe the concept of an equivalent fundamental-mode source, and we derive an expression for a factor, g?, that converts any arbitrary source distribution to its equivalent fundamental-mode source strength. We also present a new experimental method that can be employed to measure the equivalent fundamental-mode source strength in a multiplying assembly. We demonstrate the method on

Takeshi Sakurai; Shigeaki Okajima

1999-01-01

209

Simple method to estimate MOS oxide-trap, interface-trap, and border-trap densities  

SciTech Connect

Recent work has shown that near-interfacial oxide traps that communicates with the underlaying Si (``border traps``) can play a significant role in determining MOS radiation response and long-term reliability. Thermally-stimulated-current 1/f noise, and frequency-dependent charge-pumping measurements have been used to estimate border-trap densities in MOS structures. These methods all require high-precision, low-noise measurements that are often difficult to perform and interpret. In this summary, we describe a new dual-transistor method to separate bulk-oxide-trap, interface-trap, and border-trap densities in irradiated MOS transistors that requires only standard threshold-voltage and high-frequency charge-pumping measurements.

Fleetwood, D.M.; Shaneyfelt, M.R.; Schwank, J.R.

1993-09-01

210

ESD on CHMOS Devices - Equivalent Circuits, Physical Models and Failure Mechanisms  

Microsoft Academic Search

Using new techniques it is possible to construct an EOS\\/ESD equivalent circuit of a product. Location of energy dissipation during an EOS\\/ESD event is determined by a pulsed near infrared technique. Rules for predicting location of ESD dissipation are defined. N+-P-N+ structures and n-channel transistors suffer from a current lock-on effect, which is apparently caused by a runaway oxide trapping

N. Khurana; T. Maloney; W. Yeh

1985-01-01

211

36 CFR 1192.2 - Equivalent facilitation.  

Code of Federal Regulations, 2011 CFR

...2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION VEHICLES General § 1192.2 Equivalent...

2011-07-01

212

36 CFR 1192.2 - Equivalent facilitation.  

Code of Federal Regulations, 2012 CFR

...2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION VEHICLES General § 1192.2 Equivalent...

2012-07-01

213

Substantially Equivalent 510(k) Device Information  

Center for Biologics Evaluation and Research (CBER)

... Substantially Equivalent 510(k) Device Information. The following products ... fluid warmers, etc. -. List of 510(k) submissions. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

214

A single trapped ion in a finite range trap  

SciTech Connect

Research Highlights: > We present a method to describe dynamics of an ion confined in a finite size trap. > The trap is modeled with a potential in the context of an f-deformed oscillator. > The ion exhibits nonclassical properties such as squeezing and quantum interference. > . > Also this system can be used to generate highly excited motional Fock state. > The Hilbert space size effects and nano traps can be investigated by this model. - Abstract: This paper presents a method to describe dynamics of an ion confined in a realistic finite range trap. We model this realistic potential with a solvable one and we obtain dynamical variables (raising and lowering operators) of this potential. We consider coherent interaction of this confined ion in a finite range trap and we show that its center-of-mass motion steady state is a special kind of nonlinear coherent states. Physical properties of this state and their dependence on the finite range of potential are studied.

Bagheri Harouni, M., E-mail: m-bagheri@phys.ui.ac.ir [Department of Physics, Faculty of Science, University of Isfahan, Hezar Jerib St., Isfahan 81764-73441 (Iran, Islamic Republic of); Davoudi Darareh, M., E-mail: m.davoudi@sci.ui.ac.ir [Department of Physics, Faculty of Science, University of Isfahan, Hezar Jerib St., Isfahan 81764-73441 (Iran, Islamic Republic of); Department of Physics, Malek-ashtar University of Technology, Shahin-shahr, P.O. Box 83145/115 (Iran, Islamic Republic of)

2011-04-15

215

Task Superscalar: An Out-of-Order Task Pipeline  

Microsoft Academic Search

We present \\\\emph{Task Super scalar}, an abstraction of instruction-level out-of-order pipeline that operates at the task-level. Like ILP pipelines, which uncover parallelism in a sequential instruction stream, task super scalar uncovers task-level parallelism among tasks generated by a sequential thread. Utilizing intuitive programmer annotations of task inputs and outputs, the task super scalar pipeline dynamically detects inter-task data dependencies, identifies

Yoav Etsion; Felipe Cabarcas; Alejandro Rico; Alex Ramirez; Rosa M. Badia; Eduard Ayguade; Jesus Labarta; Mateo Valero

2010-01-01

216

Spacetime near isolated and dynamical trapping horizons  

NASA Astrophysics Data System (ADS)

We study the near-horizon spacetime for isolated and dynamical trapping horizons (equivalently marginally outer trapped tubes). The metric is expanded relative to an ingoing Gaussian null coordinate and the terms of that expansion are explicitly calculated to second order. For the spacelike case, knowledge of the intrinsic and extrinsic geometry of the (dynamical) horizon is sufficient to determine the near-horizon spacetime, while for the null case (an isolated horizon) more information is needed. In both cases spacetime is allowed to be of arbitrary dimension and the formalism accommodates both general relativity as well as more general field equations. The formalism is demonstrated for two applications. First, spacetime is considered near an isolated horizon and the construction is both checked against the Kerr-Newman solution and compared to the well-known near-horizon limit for stationary extremal black hole spacetimes. Second, spacetime is examined in the vicinity of a slowly evolving horizon and it is demonstrated that there is always an event horizon candidate in this region. The geometry and other properties of this null surface match those of the slowly evolving horizon to leading order and in this approximation the candidate evolves in a locally determined way. This generalizes known results for Vaidya as well as certain spacetimes known from studies of the fluid-gravity correspondence.

Booth, Ivan

2013-01-01

217

Polarization-induced torque in optical traps  

SciTech Connect

In the field of optical trapping and micromanipulation it is well known that linearly polarized Gaussian beams, which possess no inherent angular momentum, can exert an orienting torque on optically or geometrically anisotropic particles. Conservation of angular momentum requires that the application of such a torque be compensated for by an equivalent, and opposite, angular momentum flux in the beam. In the following paper we analyze this effect in terms of both the scattered field, and the mechanical torque experienced by the particle. It is demonstrated that, in general, the scattered field has a complicated form, carrying both spin and orbital angular momentum. However, we show that the variation of torque with rotation angle is identically equal to A+B sin(2{alpha}+{beta}) for arbitrarily shaped particles, where A, B, and {beta} are constants and {alpha} is the angular displacement of the major axis of the particle from the polarization direction. The scattered field, and the mechanical torque, are seen to reduce to qualitatively distinct forms that depend on the symmetry group of the scattering particle. Our findings are verified and illustrated by a series of numerical calculations of the forces and torques experienced by arbitrarily shaped particles trapped in linearly polarized Gaussian beams.

Simpson, Stephen H.; Benito, David C.; Hanna, Simon [H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

2007-10-15

218

Receptor Response in Venus's Fly-Trap  

Microsoft Academic Search

The insect-trapping movement of the plant Dionaea muscipula (Venus's fly-trap) is mediated by the stimulation of mechanosensory hairs located on the surface of the trap. It is known that stimulation of the hairs is followed by action potentials which are propagated over the surface of the trap. It has been reported that action potentials always precede trap closure, The occurrence

STUART L. JACOBSON

1965-01-01

219

pacce: Perl algorithm to compute continuum and equivalent widths  

NASA Astrophysics Data System (ADS)

We present Perl Algorithm to Compute continuum and Equivalent Widths ( pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for synthetic simple stellar population (SSP) models the equivalent widths strengths are very similar (differences ?0.2 Å) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5 Å. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics. The code is made available for the community through the web at http://www.if.ufrgs.br/~riffel/software.html .

Riffel, Rogério; Borges Vale, Tibério

2011-08-01

220

Effects of a CARO on Stimulus Equivalence Formation: A Systematic Replication  

ERIC Educational Resources Information Center

|In two experiments, we examined the disruptive effects of a "can't answer" response option (CARO) on equivalence formation. The first experiment was a systematic replication of Duarte, Eikeseth, Rosales-Ruiz, and Baer (1998), in which participants in a CARO group and a No-CARO group performed conditional discrimination tasks with abstract stimuli…

Imam, Abdulrazaq A.; Blanche, Justin V.

2013-01-01

221

Where are the trapped surfaces?  

NASA Astrophysics Data System (ADS)

We discuss the boundary of the spacetime region through each point of which a trapped surface passes, first in some simple soluble examples, and then in the self-similar Vaidya solution. For the latter the boundary must lie strictly inside the event horizon. We present a class of closed trapped surfaces extending strictly outside the apparent horizon.

Åman, Jan E.; Bengtsson, Ingemar; Senovilla, José M. M.

2010-05-01

222

Nanofriction in cold ion traps  

Microsoft Academic Search

Sliding friction between crystal lattices and the physics of cold ion traps are so far non-overlapping fields. Two sliding lattices may either stick and show static friction or slip with dynamic friction; cold ions are known to form static chains, helices or clusters, depending on the trapping conditions. Here we show, based on simulations, that much could be learnt about

A. Benassi; A. Vanossi; E. Tosatti

2011-01-01

223

Trap theory of hydrogen embrittlement  

Microsoft Academic Search

A theory has been developed that relates many particularities of hydrogen embrittlement to the behavior of the trap population of the mateial during its exposure to hydrogen. In particular, it is shown that reversible traps may act as innocuous sinks or as detrimental hydrogen sources, depending on test conditions. Two conditions will determine what role will prevail. One is related

G PRESSOUYRE

1980-01-01

224

Sympathetic Cooling of Trapped Cd^+  

Microsoft Academic Search

Trapped ions are among the most attractive candidates for quantum computing, featuring very long internal state qubit coherence times. However, decoherence of motional states can limit quantum gate fidelity. Sympathetic cooling of ions offers a method for quenching motional decoherence while preserving internal state coherence. We sympathetically cool a trapped ^112Cd^+ ion by Doppler-cooling a ^114Cd^+ ion in a Paul

Louis Deslauriers; Boris Blinov; Kathy-Anne Brickman; Patricia Lee; Martin Madsen; Russell Miller; Christopher Monroe

2002-01-01

225

Traps status in the industry  

Microsoft Academic Search

Generally, the condition of most steam systems is substandard, with identifiable steam trap failures exceeding 30%. This situation can be changed with an understanding of the purpose and function of the steam system. Steam traps are automatic control valves that open to permit the flow of condensate, yet close to prevent the flow of steam. They must be able to

1983-01-01

226

Mutual Altruism and Misery Traps  

Microsoft Academic Search

Abstract: This paper studies a neglected effect of mutual altruism, consistent with psychological findings. In the model, two individuals care for each other’s happiness. Under certain conditions, they may end up in a misery trap where each is unhappy because the other is. The misery trap coexists with another outcome, however, in which each individual enjoys the other’s happiness. The

Yann Bramoullé

227

Impurity trapping during crystal growth  

Microsoft Academic Search

A computer simulation of dendritic crystal growth was developed and used to derive a relationship between solution trapping and system and process parameters during crystal growth. The relation predicts that trapping will increase with increasing crystal growth velocity and decreasing positive and negative temperature gradients. A flow crystallizer was used to experimentally study the growth of calcium sulphate, potassium aluminum

A. S. Myerson

1977-01-01

228

Trapped surfaces in spherical stars  

SciTech Connect

We give necessary and sufficient conditions for the existence of trapped surfaces in spherically symmetric spacetimes. These conditions show that the formation of trapped surfaces depends on both the degree of concentration and the average flow of the matter. The result can be considered as a partial validation of the cosmic-censorship hypothesis.

Bizon, P.; Malec, E.; O'Murchadha, N.

1988-09-05

229

Nontoxic Antifreeze for Insect Traps  

Technology Transfer Automated Retrieval System (TEKTRAN)

Propylene glycol in water is a safe and effective alternative to ethylene glycol as a capture liquid in insect traps (pitfalls, flight intercepts, pan traps). Propylene glycol formulations are readily available because it is the primary (95%) ingredient in certain automotive antifreeze formulations...

230

Teaching Equivalence Relations Using Collaborative Activities  

ERIC Educational Resources Information Center

|The notion of equivalence relation is a fundamental concept in mathematics and yet mathematics students often are not given formal exposure to it until midway through their college careers. Not only do they need to become adept at working with equivalence relations but they should also understand the wide applicability of this notion. In this…

Mills, Janet E.

2004-01-01

231

Equivalence Relations and Behavior: An Introductory Tutorial  

ERIC Educational Resources Information Center

|With an emphasis on procedural fundamentals, the original behavior-analytic equivalence experiments and the equivalence paradigm are described briefly. A few of the subsequent developments and implications are noted, with special reference to the possible significance of the findings with respect to language and cognition. (Contains 9 figures.)|

Sidman, Murray

2009-01-01

232

Comparing Locality and Causality Based Equivalences  

Microsoft Academic Search

For CCS [15] several noninterleaving semantics have been proposed among which causal bisimulation [9] and location equivalence [6] play a central role. To unify these two approaches this paper introduces a new transition system based onlocal andglobal causes. Bisimulation equivalence is parameterized by a functionf which evaluates the information on causes provided by the transitions. Appropriate instantiations off yield characterizations

Astrid Kiehn

1994-01-01

233

CMOS Equivalent Model of Ferroelectric RAM  

Microsoft Academic Search

The current research work in the paper is the representation of FRAM (Ferroelectric Random Access Memory) as an equivalent Model of Ferroelectric memory cell in Spice Tool. This Equivalent CMOS based model is designed to work at par with the behaviour working of the FRAM. The crux of the design of ferroelectric capacitor in the Ferroelectric Random Access Memory lies

Parvinder S. Sandhu; Iqbaldeep Kaur; Amit Verma; Birinderjit S. Kalyan; Jagdeep Kaur; Sanyam Anand

2010-01-01

234

Mapping Children's Understanding of Mathematical Equivalence  

ERIC Educational Resources Information Center

|The focus of this research is to develop an initial framework for assessing and interpreting students' level of understanding of mathematical equivalence. Although this topic has been studied for many years, there has been no systematic development or evaluation of a valid measure of equivalence knowledge. A powerful method for accomplishing this…

Taylor, Roger S.; Rittle-Johnson, Bethany; Matthews, Percival G.; McEldoon, Katherine L.

2009-01-01

235

The tree equivalence of linear recursion schemes  

Microsoft Academic Search

Abstract: In the paper, a complete system of transformation rules preserving thetree equivalence and a polynomial-time algorithm deciding the tree equivalenceof linear polyadic recursion schemes are proposed. The algorithm isformulated as a sequential transformation process which brings togetherthe schemes in question. In the last step, the tree equivalence problemfor the given schemes is reduced to a global flow analysis problem

Viktor K. Sabelfeld

2000-01-01

236

Nondurable K Theory Equivalence and Bousfield Localization  

Microsoft Academic Search

In this paper we consider what happens when Adams self maps are modified by adding certain unstable maps. The unstable maps which are added are trivial after a single suspension. We can choose the modification so that the maps are still K-theory equivalences but the loops on the map are no longer K-theory equivalences. As a corollary we note that

Lisa Langsetmo; Don Stanley

2001-01-01

237

Suggested Methods for Estimating Adult Equivalence Scales  

Microsoft Academic Search

When trying to obtain an estimate of the demand function of households for certain food items, it is often convenient to express the demographic structure (size, age and sex composition) of individual households in terms of so many consumer (e.g. an adult male) equivalents. In many studies such conversions have been made by using adult equivalence scales derived from nutrionists

R. W. McShane

1971-01-01

238

When are origin and destination regimes equivalent?  

Microsoft Academic Search

A series of equivalence results are established which show that a switch from a destination regime of commodity taxation to an origin regime has no real effects. These significantly generalize those in the existing literature. Assuming uniformity of taxes within each country, equivalence applies (1) in a general competitive economy with an arbitrary (finite) number of goods and factors of

Ben Lockwood; DAVID DE MEZA; Gareth D. Myles

1994-01-01

239

Do Quantum Systems Break The Equivalence Principle?  

Microsoft Academic Search

Gravitational response of real objects is a fascinating topic. Einstein formalized the Galileo-Newton ideas of equality of free falls into complete physical equivalence or the Principle of Equivalence [Albert Einstein, The meaning of Relativity, 5 ed. Princeton, (1921)]. However, in this article we point out that in a gravitational field, g, the bulk response of an electrically neutral but atomistic

Timir Datta; Ming Yin

2009-01-01

240

Equivalence Relations and Behavior: An Introductory Tutorial  

PubMed Central

With an emphasis on procedural fundamentals, the original behavior-analytic equivalence experiments and the equivalence paradigm are described briefly. A few of the subsequent developments and implications are noted, with special reference to the possible significance of the findings with respect to language and cognition.

Sidman, Murray

2009-01-01

241

Epidermal growth in the skin equivalent  

Microsoft Academic Search

The skin equivalent (SE) has been validated as a model for studies on proliferation of keratinocytes. SEs were prepared from normal skin by implanting punch biopsies on dermal equivalents consisting of fibroblasts in a collagen matrix. The outgrowths were measured by planimetry. An immunohistochemical investigation with antibodies against markers associated with proliferation was performed on frozen sections from SEs during

J. Fransson; H. Hammar

1992-01-01

242

Equivalence in Ventilation and Indoor Air Quality  

SciTech Connect

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

Sherman, Max; Walker, Iain; Logue, Jennifer

2011-08-01

243

On the equivalence principle in quantum theory  

SciTech Connect

The role of the equivalence principle in the context of non-relativistic quantum mechanics and matter wave interferometry, especially atom beam interferometry, will be discussed. A generalized form of the weak equivalence principle which is capable of covering quantum phenomena too, will be proposed. It is shown that this generalized equivalence principle is valid for matter wave interferometry and for the dynamics of expectation values. In addition, the use of this equivalence principle makes it possible to determine the structure of the interaction of quantum systems with gravitational and inertial fields. It is also shown that the path of the mean value of the position operator in the case of gravitational interaction does fulfill this generalized equivalence principle.

Laemmerzahl, C. [Universite Pierre et Marie Curie, Paris (France)

1996-09-01

244

Task Communication in DEMOS  

Microsoft Academic Search

This paper describes the fundamentals and some of the details of task communication in DEMOS, the operating system for the CRAY-I computer being developed at the Los Alamos Scientific Laboratory. The communication mechan- ism is a message system with several novel features. Messages are sent from one task to another over links. Links are the primary protected objects in the

Forest Baskett; John H. Howard; John T. Montague

1977-01-01

245

Narcissism and Task Persistence  

Microsoft Academic Search

Two studies investigated narcissists' persistence in attempting impossible tasks framed as intelligence tests. Narcissism predicted more task persistence when no alternative paths to self-enhancement were available (Study 1) and less persistence when alternative routes to self-enhancement were provided (Study 2). Overall, the results suggest that narcissists can maintain confidence and tolerate setbacks in pursuit of a goal, but may quickly

Harry M. Wallace; C. Beth Ready; Erin Weitenhagen

2009-01-01

246

The Multiple Tasks Test  

Microsoft Academic Search

Simultaneous challenge of posture and cognition (‘dual tasks’) may predict falls better than tests of isolated components of postural control. We describe a new balance test (the Multiple Tasks Test, MTT) which (1) is based upon simultaneous assessment of multiple (>2) postural components; (2) represents everyday situations; and (3) can be applied by clinicians. Relevant risk factors for falls and

Bastiaan R Bloem; Vibeke V Valkenburg; Mathilde Slabbekoorn; Mirjam D Willemsen

2001-01-01

247

Debugging Ada Tasking Programs  

Microsoft Academic Search

A new c\\/ass of errors, not found in sequential languages, can result when the tasking constructs of Ada are used. These errors are called deadness errors and arise when task communication fails. Since deadness errors often occur intermittently, they are particularly hard to detect and diagnose. Previous papers, (2) and (4), describe the theory and implementation of runtime monitors to

David Helmbold; David Luckham

1984-01-01

248

4.NF Explaining Fraction Equivalence with Pictures  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: The rectangle below has length 1. What fraction does the shaded part represent? The rectangle below has the same length as the rectangle above. What fr...

249

The trapped human experiment.  

PubMed

This experiment observed the evolution of metabolite plumes from a human trapped in a simulation of a collapsed building. Ten participants took it in turns over five days to lie in a simulation of a collapsed building and eight of them completed the 6 h protocol while their breath, sweat and skin metabolites were passed through a simulation of a collapsed glass-clad reinforced-concrete building. Safety, welfare and environmental parameters were monitored continuously, and active adsorbent sampling for thermal desorption GC-MS, on-line and embedded CO, CO(2) and O(2) monitoring, aspirating ion mobility spectrometry with integrated semiconductor gas sensors, direct injection GC-ion mobility spectrometry, active sampling thermal desorption GC-differential mobility spectrometry and a prototype remote early detection system for survivor location were used to monitor the evolution of the metabolite plumes that were generated. Oxygen levels within the void simulator were allowed to fall no lower than 19.1% (v). Concurrent levels of carbon dioxide built up to an average level of 1.6% (v) in the breathing zone of the participants. Temperature, humidity, carbon dioxide levels and the physiological measurements were consistent with a reproducible methodology that enabled the metabolite plumes to be sampled and characterized from the different parts of the experiment. Welfare and safety data were satisfactory with pulse rates, blood pressures and oxygenation, all within levels consistent with healthy adults. Up to 12 in-test welfare assessments per participant and a six-week follow-up Stanford Acute Stress Response Questionnaire indicated that the researchers and participants did not experience any adverse effects from their involvement in the study. Preliminary observations confirmed that CO(2), NH(3) and acetone were effective markers for trapped humans, although interactions with water absorbed in building debris needed further study. An unexpected observation from the NH(3) channel was the suppression of NH(3) during those periods when the participants slept, and this will be the subject of further study, as will be the detailed analysis of the casualty detection data obtained from the seven instruments used. PMID:21908906

Huo, R; Agapiou, A; Bocos-Bintintan, V; Brown, L J; Burns, C; Creaser, C S; Devenport, N A; Gao-Lau, B; Guallar-Hoyas, C; Hildebrand, L; Malkar, A; Martin, H J; Moll, V H; Patel, P; Ratiu, A; Reynolds, J C; Sielemann, S; Slodzynski, R; Statheropoulos, M; Turner, M A; Vautz, W; Wright, V E; Thomas, C L P

2011-09-12

250

Combined acoustic and optical trapping.  

PubMed

Combining several methods for contact free micro-manipulation of small particles such as cells or micro-organisms provides the advantages of each method in a single setup. Optical tweezers, which employ focused laser beams, offer very precise and selective handling of single particles. On the other hand, acoustic trapping with wavelengths of about 1 mm allows the simultaneous trapping of many, comparatively large particles. With conventional approaches it is difficult to fully employ the strengths of each method due to the different experimental requirements. Here we present the combined optical and acoustic trapping of motile micro-organisms in a microfluidic environment, utilizing optical macro-tweezers, which offer a large field of view and working distance of several millimeters and therefore match the typical range of acoustic trapping. We characterize the acoustic trapping forces with the help of optically trapped particles and present several applications of the combined optical and acoustic trapping, such as manipulation of large (75 ?m) particles and active particle sorting. PMID:22025990

Thalhammer, G; Steiger, R; Meinschad, M; Hill, M; Bernet, S; Ritsch-Marte, M

2011-09-27

251

Combined acoustic and optical trapping  

PubMed Central

Combining several methods for contact free micro-manipulation of small particles such as cells or micro-organisms provides the advantages of each method in a single setup. Optical tweezers, which employ focused laser beams, offer very precise and selective handling of single particles. On the other hand, acoustic trapping with wavelengths of about 1 mm allows the simultaneous trapping of many, comparatively large particles. With conventional approaches it is difficult to fully employ the strengths of each method due to the different experimental requirements. Here we present the combined optical and acoustic trapping of motile micro-organisms in a microfluidic environment, utilizing optical macro-tweezers, which offer a large field of view and working distance of several millimeters and therefore match the typical range of acoustic trapping. We characterize the acoustic trapping forces with the help of optically trapped particles and present several applications of the combined optical and acoustic trapping, such as manipulation of large (75 ?m) particles and active particle sorting.

Thalhammer, G.; Steiger, R.; Meinschad, M.; Hill, M.; Bernet, S.; Ritsch-Marte, M.

2011-01-01

252

Quantum equivalence principle without mass superselection  

NASA Astrophysics Data System (ADS)

The standard argument for the validity of Einstein's equivalence principle in a non-relativistic quantum context involves the application of a mass superselection rule. The objective of this work is to show that, contrary to widespread opinion, the compatibility between the equivalence principle and quantum mechanics does not depend on the introduction of such a restriction. For this purpose, we develop a formalism based on the extended Galileo group, which allows for a consistent handling of superpositions of different masses, and show that, within such scheme, mass superpositions behave as they should in order to obey the equivalence principle.

Hernandez-Coronado, H.; Okon, E.

2013-11-01

253

Traps status in the industry  

SciTech Connect

Generally, the condition of most steam systems is substandard, with identifiable steam trap failures exceeding 30%. This situation can be changed with an understanding of the purpose and function of the steam system. Steam traps are automatic control valves that open to permit the flow of condensate, yet close to prevent the flow of steam. They must be able to remove air, non condensible gas, and condensate, and they must respond to changes in the amount of condensate or load. The author describes the three basic types of trap and their applications.

Geiger, W.

1983-01-01

254

Equating tasks and sustaining attention in children and adults: The methodological and theoretical utility of d’ matching  

Microsoft Academic Search

The present study develops a method to create task equivalency for children and adults in vigilance research. Experiment 1\\u000a employed the signal detection index of perceptual sensitivity (d’) to calibrate vigilance tasks for 32 children (ages 78)\\u000a and 32 adults. The results of Experiment 1 suggest that task equivalency across groups can be attained, and a vigilance decrement\\u000a was observed

Cynthia Laurie-Rose; Laura Bennett-Murphy; Lori M Curtnindale; Andrea L. Granger; Heidi B. Walker

2005-01-01

255

Three-phase measurements of oil and gas trapping in sand packs  

NASA Astrophysics Data System (ADS)

We measure the trapped saturations of oil and gas as a function of initial saturation in water-wet sand packs. We start with a water-saturated column and inject octane (oil), while water and oil are produced from the bottom. Once water production has ceased, air (gas) then enters from the top, allowing oil and gas to drain under gravity for different times. Finally water is then injected from the bottom to trap both oil and gas. The columns are sliced and the fluids analyzed using gas chromatography. We find that for high initial gas saturations more gas can be trapped in the presence of oil than in a two-phase (gas/water) system. The residual gas saturation can be over 20% compared to 14% in two-phase flow [Al Mansoori SK, Iglauer S, Pentland CH, Bijeljic B, Blunt MJ. Measurements of non-wetting phase trapping applied to carbon dioxide storage. Energy Procedia 2009;1(1):3173-80]. This is unlike previous measurements on consolidated media, where the trapped gas saturation is either similar or lower to that reached in an equivalent two-phase experiment. For lower initial gas saturation, the amount of trapping follows the initial-residual trend seen in two-phase experiments. The amount of oil trapped is insensitive to initial gas saturation or the amount of gas that is trapped, again in contrast to measurements on consolidated media. More oil is trapped than would be predicted from an equivalent two-phase (oil/water) system, although the trapped saturation is never larger than the maximum reached in two-phase flow (around 11%) [Pentland CH, Al Mansoori SK, Iglauer S, Bijeljic B, Blunt MJ. Measurement of non-wetting phase trapping in sand packs. In: SPE 115697, proceedings of the SPE annual technical conference and exhibition, Denver, Colorado, USA; 21-24 September 2008]. These initially surprising results are explained in the context of oil layer stability and the competition between snap-off and piston-like advance. In two-phase systems, displacement is principally by cooperative piston-like advance with relatively little trapping, whereas in consolidated media snap-off is generally more significant. However, oil layer collapse events during three-phase waterflooding rapidly trap the oil which acts as a barrier to direct water/gas displacement, except by snap-off, leading to enhanced gas trapping.

Al Mansoori, Saleh K.; Iglauer, Stefan; Pentland, Christopher H.; Blunt, Martin J.

256

Relating equivalence relations to equivalence relations: A relational framing model of complex human functioning  

PubMed Central

The current study aimed to develop a behavior-analytic model of analogical reasoning. In Experiments 1 and 2 subjects (adults and children) were trained and tested for the formation of four, three-member equivalence relations using a delayed matching-to-sample procedure. All subjects (Experiments 1 and 2) were exposed to tests that examined relations between equivalence and non-equivalence relations. For example, on an equivalence-equivalence relation test, the complex sample B1/C1 and the two complex comparisons B3/C3 and B3/C4 were used, and on a nonequivalence-nonequivalence relation test the complex sample B1/C2 was presented with the same two comparisons. All subjects consistently related equivalence relations to equivalence relations and nonequivalence relations to nonequivalence relations (e.g., picked B3/C3 in the presence of B1/C1 and picked B3/C4 in the presence of B1/C2). In Experiment 3, the equivalence responding, the equivalence-equivalence responding, and the nonequivalence-nonequivalence responding was successfully brought under contextual control. Finally, it was shown that the contextual cues could function successfully as comparisons, and the complex samples and comparisons could function successfully as contextual cues and samples, respectively. These data extend the equivalence paradigm and contribute to a behaviour-analytic interpretation of analogical reasoning and complex human functioning, in general.

Barnes, Dermot; Hegarty, Neil; Smeets, Paul M.

1997-01-01

257

7 CFR 1131.54 - Equivalent price.  

Code of Federal Regulations, 2012 CFR

...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Class Prices § 1131.54 Equivalent price. See § 1000.54....

2012-01-01

258

21 CFR 26.6 - Equivalence assessment.  

Code of Federal Regulations, 2013 CFR

...HEALTH AND HUMAN SERVICES GENERAL MUTUAL RECOGNITION OF PHARMACEUTICAL GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL DEVICE...THE EUROPEAN COMMUNITY Specific Sector Provisions for Pharmaceutical Good Manufacturing Practices § 26.6 Equivalence...

2013-04-01

259

21 CFR 26.9 - Equivalence determination.  

Code of Federal Regulations, 2013 CFR

...HEALTH AND HUMAN SERVICES GENERAL MUTUAL RECOGNITION OF PHARMACEUTICAL GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL DEVICE...THE EUROPEAN COMMUNITY Specific Sector Provisions for Pharmaceutical Good Manufacturing Practices § 26.9 Equivalence...

2013-04-01

260

Equivalent multipole operators for degenerate Rydberg states  

NASA Astrophysics Data System (ADS)

As shown by Pauli, [Z. Phys. 36, 336 (1926)], the electric dipole operator r can be replaced by the Runge-Lenz vector A when operating within the n2 degenerate manifold of hydrogenic states of principal quantum number n . We seek to develop similar rules for higher multipole operators by expressing equivalent operators in terms only of the two vector constants of motion—the orbital angular momentum L and the Runge-Lenz vector A —appropriate to the degenerate hydrogenic shell. Equivalence of two operators means here that they yield identical matrix elements within a subspace of Hilbert space that corresponds to fixed n . Such equivalent-operator techniques permit direct algebraic calculation of perturbations of Rydberg atoms by external fields and often exact analytical results for transition probabilities. Explicit expressions for equivalent quadrupole and octupole operators are derived, examples are provided, and general aspects of the problem are discussed.

Ostrovsky, V. N.; Vrinceanu, D.; Flannery, M. R.

2006-08-01

261

7 CFR 1006.54 - Equivalent price.  

Code of Federal Regulations, 2012 CFR

...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Class Prices § 1006.54 Equivalent price. See § 1000.54....

2012-01-01

262

On asymptotically generalized statistical equivalent set sequences  

NASA Astrophysics Data System (ADS)

In this paper we shall study the asymptotically ?-statistical equivalent (Wijsman sense) of multiple L. In addition to these definition, natural inclusion theorems shall also be presented. This approach has not been considered in any context before.

Savas, Ekrem

2013-10-01

263

Equivalence Principle and Bound Kinetic Energy  

NASA Astrophysics Data System (ADS)

We consider the role of the internal kinetic energy of bound systems of matter in tests of the Einstein equivalence principle. Using the gravitational sector of the standard model extension, we show that stringent limits on equivalence principle violations in antimatter can be indirectly obtained from tests using bound systems of normal matter. We estimate the bound kinetic energy of nucleons in a range of light atomic species using Green’s function Monte Carlo calculations, and for heavier species using a Woods-Saxon model. We survey the sensitivities of existing and planned experimental tests of the equivalence principle, and report new constraints at the level of between a few parts in 106 and parts in 108 on violations of the equivalence principle for matter and antimatter.

Hohensee, Michael A.; Müller, Holger; Wiringa, R. B.

2013-10-01

264

Equivalence principle and bound kinetic energy.  

PubMed

We consider the role of the internal kinetic energy of bound systems of matter in tests of the Einstein equivalence principle. Using the gravitational sector of the standard model extension, we show that stringent limits on equivalence principle violations in antimatter can be indirectly obtained from tests using bound systems of normal matter. We estimate the bound kinetic energy of nucleons in a range of light atomic species using Green's function Monte Carlo calculations, and for heavier species using a Woods-Saxon model. We survey the sensitivities of existing and planned experimental tests of the equivalence principle, and report new constraints at the level of between a few parts in 10^{6} and parts in 10^{8} on violations of the equivalence principle for matter and antimatter. PMID:24160587

Hohensee, Michael A; Müller, Holger; Wiringa, R B

2013-10-11

265

Equivalent multipole operators for degenerate Rydberg states  

SciTech Connect

As shown by Pauli, [Z. Phys. 36, 336 (1926)], the electric dipole operator r can be replaced by the Runge-Lenz vector A when operating within the n{sup 2} degenerate manifold of hydrogenic states of principal quantum number n. We seek to develop similar rules for higher multipole operators by expressing equivalent operators in terms only of the two vector constants of motion - the orbital angular momentum L and the Runge-Lenz vector A - appropriate to the degenerate hydrogenic shell. Equivalence of two operators means here that they yield identical matrix elements within a subspace of Hilbert space that corresponds to fixed n. Such equivalent-operator techniques permit direct algebraic calculation of perturbations of Rydberg atoms by external fields and often exact analytical results for transition probabilities. Explicit expressions for equivalent quadrupole and octupole operators are derived, examples are provided, and general aspects of the problem are discussed.

Ostrovsky, V. N.; Vrinceanu, D.; Flannery, M. R. [V. Fock Institute of Physics, St. Petersburg State University, 198904 St. Petersburg (Russian Federation); Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2006-08-15

266

46 CFR 161.002-17 - Equivalents.  

Code of Federal Regulations, 2011 CFR

...CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL ELECTRICAL EQUIPMENT Fire-Protective Systems § 161.002-17...Commandant (CG-521). If necessary, the Commandant may require engineering evaluations and tests to demonstrate the equivalence of...

2011-10-01

267

Quantum equivalence of antisymmetric tensor field theories.  

National Technical Information Service (NTIS)

We show in a very simple way that the quantum equivalence of massless antisymmetric second rank tensor field theories with massless scalar and gauge theories in four and five dimensions, respectively. The technique can be straightforwardly extended to hig...

V. O. Rivelles L. Sandoval

1990-01-01

268

A criticism of healthy-years equivalents.  

PubMed

The following questions describe the scope of this paper. When decision trees are used to analyze optimal decisions, should end nodes be evaluated on the basis of QALYs or on the basis of healthy-years equivalents? Which measures should be used in communications with others, e.g., patients? Which of these measures incorporate risk attitudes, and which do not? It is demonstrated that the healthy-years equivalent measure does not stand scrunity. PMID:8818117

Wakker, P

269

Arthroscopic Transosseous-Equivalent Rotator Cuff Repair  

PubMed Central

Rotator cuff repair techniques continue to evolve in an effort to improve repair biomechanics, maximize the biologic environment for tendon healing, and ultimately improve patient outcomes. The arthroscopic transosseous-equivalent technique was developed to replicate the favorable tendon-bone contact area for healing seen in open transosseous tunnel repair. In this technical note and accompanying video, we present our all-arthroscopic transosseous-equivalent rotator cuff repair technique with a focus on technical pearls.

Lavery, Kyle P.; Rasmussen, Jeffrey F.; Dhawan, Aman

2013-01-01

270

Multilingual energy dictionary. [Equivalents in 6 languages  

SciTech Connect

This dictionary covers 1600 entries - ranging from oil well to synthetic natural gas and waste heat recovery - that cover both concepts and equipment, providing the equivalents of the most-important energy terms in six languages: English, French, German, Italian, Portuguese, and Spanish. Each term is listed six times - under each language, with all five foreign equivalents - permitting easy translation among all six languages. Separate entries are also given for British and American English where usage differs in the two countries.

Isaacs, A. (ed.)

1981-01-01

271

GPS data processing with equivalent observation equations  

Microsoft Academic Search

.   A unified GPS data processing method based on equivalent observation equations is proposed. The theoretic background of this\\u000a method is given in detail. By selecting the unknowns to be eliminated as vector of zeros, i.e. the satellite clock errors,\\u000a all clock errors, the clock and ambiguity parameters or user-defined unknowns, the equivalent observation equations can be\\u000a formed. These equations

Guochang Xu

2002-01-01

272

Dioxin Toxic Equivalent Concentrations in Wood Ash  

Microsoft Academic Search

The purpose of this study was to quantify toxic equivalent (TEQ) concentrations of polychlorinated dibenzo- p -dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and polychlorinated biphenyls (PCB) in ash residues generated by wood-fired boilers in Washington state (USA). With non-detects (ND) set to one-half the detection limit (DL) and employing mammalian toxic equivalency factors (TEF) recommended by the World Health Organization (WHO),

Damon A. Delistraty; Stacie A. Singleton

2002-01-01

273

Evaporative cooling of trapped atoms  

SciTech Connect

This report discusses the following topics on evaporative cooling of trapped atoms: Theoretical models for evaporative cooling; the role of collisions for real atoms; experimental techniques and summary of evaporative cooling experiments. 166 refs., 6 figs., 3 tabs.

Ketterle, W.; Van Druten, N.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

1996-12-31

274

Evaporative Cooling of Trapped Atoms  

Microsoft Academic Search

This report discusses the following topics on evaporative cooling of trapped atoms: Theoretical models for evaporative cooling; the role of collisions for real atoms; experimental techniques and summary of evaporative cooling experiments. 166 refs., 6 figs., 3 tabs.

Wolfgang Ketterle; N. J. Van Druten

1996-01-01

275

Vortex dynamics in anisotropic traps  

SciTech Connect

We investigate the dynamics of linear vortex lattices in anisotropic traps in two dimensions and show that the interplay between the rotation and the anisotropy leads to a rich but highly regular dynamics.

McEndoo, S.; Busch, Th. [Department of Physics, University College Cork, Cork (Ireland)

2010-07-15

276

Equivalence Relations, Contextual Control, and Naming  

PubMed Central

This paper reports two experiments that investigated the role of verbal behavior in the emergence and generalization of contextually controlled equivalence classes. During both experiments, participants were trained with two different combinations of the same easily nameable, yet formally unrelated, pictorial stimuli. Match-to-sample baselines for eight four-member classes were established under the contextual control of two colors. In the presence of one color, conditional relations were established between stimuli whose normative names rhymed. In the presence of the other color, conditional relations were established between stimuli whose normative names did not rhyme. Although, during Experiment 1, all participants demonstrated equivalence classes involving rhyming stimuli, none demonstrated the formation of nonrhyme equivalence classes. To investigate this finding, Experiment 2 evaluated whether participants would demonstrate both rhyme and nonrhyme equivalence classes given more extensive exposure to the experimental contingencies. All participants demonstrated contextually controlled rhyme and nonrhyme equivalence classes, although rhyme classes were demonstrated with greater facility than nonrhyme classes. Results indicate that visual stimuli are named, that verbal bases for stimulus classification can affect the emergence of contextually controlled equivalence classes, and that untrained contextually controlled conditional discriminations involving novel stimuli can emerge on the basis of participants' verbal behavior.

Randell, Tom; Remington, Bob

2006-01-01

277

Spin trapping artifacts in DMSO  

Microsoft Academic Search

Spin-trapping experiments in alkaline aqueous dimethyl sulfoxide (DMSO) solution using sodium 3,5-dibromo-4-nitrosobenzenesulfonate (DBNBS) yielded a strong signal of the sulfur trioxide anion radical adduct. This radical adduct is identical to that obtained by the oxidation of sulfite with horseradish peroxidase\\/hydrogen peroxide and subsequent spin trapping with DBNBS. This radical adduct is very stable, and satellite peaks of the natural abundance

K. Stolze; R. P. Mason

1987-01-01

278

Globalization Task Force Report.  

National Technical Information Service (NTIS)

Since the last meeting of the President's National Security Telecommunications Advisory Committee (NSTAC) in June 1999, the Globalization Task Force (GTF)1 has concentrated its efforts on national security and emergency preparedness (NS/EP) issues related...

2000-01-01

279

Debugging Ada Tasking Programs  

Microsoft Academic Search

Debuggers for parallel programs have to be more than passive information gatherers-they should automatically detect errors. Powerful task debuggers for Ada can be constructed by extending existing tools that detect deadlock.

D. Heimbold; D. Luckham

1985-01-01

280

Task switching and multitask performance  

Microsoft Academic Search

ABSTRACT Research on task ,switching and dual-task performance ,has spawned ,two lit- eratures that have, to a surprising extent, developed independently. This tutorial reviews the principal findings of each ,tradition and considers how ,these phenomena ,may ,be related. Beginning with Jersild 1927, task-switching studies reveal that when people perform two tasks in succession, with each task requiring different responses to

H. Pashler

2000-01-01

281

Hypnosis, task-motivating instructions, and learning performance  

Microsoft Academic Search

40 Ss, including 30 who had been previously rated as suggestible and 10 as nonsuggestible, were pretested and then retested on equivalent forms of 3 learning tasks: digit symbol substitution, memory for words, and abstract reasoning. All Ss received the pretests in the same way. The 30 suggestible Ss were retested under 1 of the following 3 experimental treatments with

Paul D. Parker; Theodore X. Barber

1964-01-01

282

Interstitial trapped hydrogen molecules in PECVD amorphous silicon  

SciTech Connect

New NMR measurements show that interstitial T site-trapped molecular hydrogen can amount to more than one third of the contained hydrogen in high quality PECVD amorphous silicon. Microvoid-contained dense molecular hydrogen is negligible in these good films. Experiments on a sequence of hydrogenated and/or deuterated a-Si films have characterized individually-trapped molecular HD and D{sub 2} in films deposited from SiD{sub 4}, and from SiH{sub 4}+D{sub 2}. The T site-trapped molecular hydrogen fraction observed here is larger than previously reported because of recent efforts to measure very slowly relaxing molecular components and the employment of radiofrequency pulse sequences to detect ortho-D{sub 2} with nuclear spin I = 2. The population of interstitially trapped molecular hydrogen increases with increasing photovoltaic quality over a range of an order of magnitude in photoresponse product {eta}{mu}{tau}. Above 200 K, hopping transport of molecular hydrogen among the amorphous equivalent of interstitial T sites occurs with an activation energy near 50 meV.

Borzi, R.; Mascarenhas, F.; Fedders, P.A.; Leopold, D.J.; Norberg, R.E.; Wickboldt, P.; Paul, W.

1999-07-01

283

Design and development of human equivalent inspection system  

NASA Astrophysics Data System (ADS)

The human visual system engages a wide field of view peripheral vision in conjunction with selectively scanned high resolution foveal vision. The effective scene resolution of the human eye is equivalent to a camera with 108 pixels. This performance is difficult if not impossible to match with available camera technologies. Canpolar East has recently developed a machine vision system that utilizes a low resolution wide field camera plus a high resolution narrow field camera that is able to fixate at 30/60 frames per second. The system was specifically designed to match human visual performance in industrial inspection tasks. The system includes software that selects objects of interest from the low resolution images for high resolution imaging. The system is capable of selection and fixation at about 25 'saccades' per second.

Mazour, A.; King, Stephen

1997-06-01

284

Zonal Dynamic Equivalents Based on the Concept of Relative Electrical Distance  

NASA Astrophysics Data System (ADS)

Abstract: This article presents a systematic approach to construct the zonal dynamic equivalents of a large-power system based on the concept of relative electrical distance (RED). The task of dynamic equivalencing is to eliminate the full model of the external system and replace it with an equivalent model, which has dynamic characteristics close enough to the full model. The dynamic equivalent models are used for large-scale power system offline transient stability analysis with large disturbance. Dynamic equivalencing also helps in reducing the computation burden and memory requirements in wide area monitoring system (WAMS) for online stability assessment. The procedure is illustrated on IEEE 39 bus system and on a practical 205 bus system consisting of three zones of Indian Southern grid, where an equivalent of a zone has been constructed. The simulation results of the original system and equivalent system are compared. The proposed approach is also compared with the existing Ward equivalent method and the results are found to be similar. The simulation results show that the developed equivalent system has close accuracy in representing the dynamic characteristics of the original system.

Agrawal, Rimjhim; Dhadbanjan, Thukaram

2013-05-01

285

Ion trap technology at accelerator facilities  

Microsoft Academic Search

Ion traps allow the capture, accumulation and confinement of charged particles at rest, in vacuum. These particles can then be manipulated and studied at will in the traps or transferred to other devices. The present paper will discuss the trapping mechanisms, concentrating on capture of externally created ions, for different types of ion traps. It will then discuss the advantage

G. Savard

1996-01-01

286

Ion trap technology at accelerator facilities  

Microsoft Academic Search

Ion traps allow the capture, accumulation and confinement of charged particles at rest, in vacuum. These particles can then be manipulated and studied at will in the traps or transferred to other devices. The present paper will discuss the trapping mechanisms, concentrating on capture of externally created ions, for different types of ion traps. It will then discuss the advantage

G. Savard

1997-01-01

287

All steam traps aren`t equal  

Microsoft Academic Search

Steam traps are automatic valves that sense the difference between steam, air, condensate, and noncondensate gases such as COâ. Their objective is to purge air, condensate, and other noncondensate gases and trap steam in the system where it belongs. A properly working trap should never let steam escape. Though the requirements for steam traps are simple, even the most experienced

Picut

1996-01-01

288

Sediment trap assemblages — a methodological description  

Microsoft Academic Search

A short description is given of the theory and use of sediment traps in the context of fine sediment dynamics. The technical construction of the sediment trap device has been examined earlier. Sediment traps yield data on rates of sedimentation and provide a means of estimating redeposition and resuspension. Methods for distinguishing between primary and secondary material in the traps

Lars Håkanson; Sören Floderus; Mats Wallin

1989-01-01

289

All steam traps are not equal  

Microsoft Academic Search

Proper selection of a steam trap will result in a long-lasting, trouble-free steam distribution system. The definition of a trap is simple enough: it should get rid of air and purge off noncondensibles when the system is started up and drain condensate anytime during operation. This is the reason traps are sometimes called automatic drain valves. A steam trap should

Alesson

1995-01-01

290

Note: Toward multiple addressable optical trapping  

PubMed Central

We describe a setup for addressable optical trapping in which a laser source is focused on a digital micromirror device and generates an optical trap in a microfluidic cell. In this paper, we report a proof-of-principle single beam?single micromirror?single three-dimensional trap arrangement that should serve as the basis for a multiple-trap instrument.

Faustov, Alexei R.; Webb, Michael R.; Walt, David R.

2010-01-01

291

A Microscale Gas Trapping Investigation  

NASA Astrophysics Data System (ADS)

Immobilization and trapping of CO2 enhances its geological storage security. The trapping mechanism has been characterized into four main groups: structural, residual, dissolution and mineralization. While structural trapping acts immediately when injection starts and is well investigated, residual and dissolution trapping contribution increase over geological storage time and need to be better understood to develop more accurate models and simulator predictions. Dissolution trapping is controlled by a phase equilibrium process. The local equality of fugacities in the aqueous and the gas phase determines the amount of CO2 to be transferred. Complete dissolution of a single gas bubble can only happen after the continuous gas phase has been disconnected and immobilized by capillary trapping. This process on the other hand is governed by flow rate and pore body to throat size in the porous media. In this study, we focus on an experimental pore-scale investigation of residual and capillary trapping. Our work is a precursor to designing storage processes with enhancing storage security. In the present work, CO2-water imbibition experiments were conducted in visual micromodels whose pore space is geometrically and topologically similar to Berea sandstone. High -resolution, micro-visual data, in the form of photographs and video footage, describes the trapping mechanism and especially the disconnection and shrinkage of the CO2 phase in various phase conditions (gas-liquid-supercritical). During final bubble dissolution, special emphasis was placed on the homogeneous and heterogonous dissolution cases and their impact on storage security. Results show that the depending on the flow rate of the imbibing water different trapping mechanism are observed. Lower rates comparable to the trailing edge of the CO2 plume led to a greater frequency of snap off events and greater trapped residual saturation whereas higher rates comparable to the near wellbore area during enhanced sequestration (CO2-water alternating injection) showed displacement of gas bubbles and greater dissolution rates that ultimately leads to very low or zero gas saturation. Furthermore complete dissolution events showed that homogenous as well as heterogeneous dissolution occurs, whereas the latter could be subdivided into microbubble formation and dissolution on crevices or pore roughness. Based on the observations we can conclude that the type of rock and its roughness as well as the fines present in the brine are important factors determining the dissolution mechanism.

Buchgraber, M.; Kovscek, A. R.

2011-12-01

292

Effects of oxide traps, interface traps, and border traps'' on metal-oxide-semiconductor devices  

SciTech Connect

We have identified several features of the 1/[ital f] noise and radiation response of metal-oxide-semiconductor (MOS) devices that are difficult to explain with standard defect models. To address this issue, and in response to ambiguities in the literature, we have developed a revised nomenclature for defects in MOS devices that clearly distinguishes the language used to describe the physical location of defects from that used to describe their electrical response. In this nomenclature, oxide traps'' are simply defects in the SiO[sub 2] layer of the MOS structure, and interface traps'' are defects at the Si/SiO[sub 2] interface. Nothing is presumed about how either type of defect communicates with the underlying Si. Electrically, fixed states'' are defined as trap levels that do not communicate with the Si on the time scale of the measurements, but switching states'' can exchange charge with the Si. Fixed states presumably are oxide traps in most types of measurements, but switching states can either be interface traps or near-interfacial oxide traps that can communicate with the Si, i.e., border traps'' [D. M. Fleetwood, IEEE Trans. Nucl. Sci. [bold NS]-[bold 39], 269 (1992)]. The effective density of border traps depends on the time scale and bias conditions of the measurements. We show the revised nomenclature can provide focus to discussions of the buildup and annealing of radiation-induced charge in non-radiation-hardened MOS transistors, and to changes in the 1/[ital f] noise of MOS devices through irradiation and elevated-temperature annealing.

Fleetwood, D.M.; Winokur, P.S.; Reber, R.A. Jr.; Meisenheimer, T.L.; Schwank, J.R.; Shaneyfelt, M.R.; Riewe, L.C. (Sandia National Laboratories, Department 1332, Albuquerque, New Mexico 87185-5800 (United States))

1993-05-15

293

Live trapping of hawks and owls  

USGS Publications Warehouse

1. Hawks of six species (80 individuals) and owls of five species (37 individuals) were trapped for banding from November 1, 1943, to. May 26,1944. 2. In general, pole traps proved better than hand-operated traps or automatic traps using live bait. 3. Verbail pole traps proved very efficient, and were much more humane than padded steel traps because they rarely injured a captured bird. 4: Unbaited Verbail traps took a variety of raptors, in rough proportion to their local abundance, although slightly more of beneficial species were caught than of harmful types. 5. Hawks and owls were retrapped more readily in Verbail traps than in other types tried. 6. The number of song birds caught in Verbail traps was negligible. 7. Crows and vultures were not taken in Verbail traps, but possibly could be caught with bait.

Stewart, R.E.; Cope, J.B.; Robbins, C.S.

1945-01-01

294

Tool for Automatic Measurement of Equivalent width (TAME)  

NASA Astrophysics Data System (ADS)

We present a tool for measuring the equivalent width (EW) in high-resolution spectra. The Tool for Automatic Measurement of Equivalent width (TAME) provides the EWs of spectral lines by profile fitting in an automatic or interactive mode, which can yield a more precise result through the adjustment of the local continuum and fitting parameters. The automatic EW results of TAME have been verified by comparing them with the manual EW measurements by the IRAF splot task using the high-resolution spectrum of the Sun and measuring EWs in the synthetic spectra with different spectral resolutions and signal-to-noise (S/N) ratios. The EWs measured by TAME agree well with the manually measured values, with a dispersion of less than 2 mÅ. By comparing the input EWs for synthetic spectra and EWs measured by TAME, we conclude that it is reliable for measuring the EWs in a spectrum with a spectral resolution of R ? 20 000 and find that the errors in EWs are less than 1 mÅ for an S/N ratio ?100.

Kang, Wonseok; Lee, Sang-Gak

2012-10-01

295

Application of plasmonic bowtie nanoantenna arrays for optical trapping, stacking, and sorting.  

PubMed

We present the use of Au bowtie nanoantenna arrays (BNAs) for highly efficient, multipurpose particle manipulation with unprecedented low input power and low-numerical aperture (NA) focusing. Optical trapping efficiencies measured are up to 20× the efficiencies of conventional high-NA optical traps and are among the highest reported to date. Empirically obtained plasmonic optical trapping "phase diagrams" are introduced to detail the trapping response of the BNAs as a function of input power, wavelength, polarization, particle diameter, and BNA array spacing (number density). Using these diagrams, parameters are chosen, employing strictly the degrees-of-freedom of the input light, to engineer specific trapping tasks including (1) dexterous, single-particle trapping and manipulation, (2) trapping and manipulation of two- and three-dimensional particle clusters, and (3) particle sorting. The use of low input power densities (power and NA) suggests that this bowtie nanoantenna trapping system will be particularly attractive for lab-on-a-chip technology or biological applications aimed at reducing specimen photodamage. PMID:22208881

Roxworthy, Brian J; Ko, Kaspar D; Kumar, Anil; Fung, Kin Hung; Chow, Edmond K C; Liu, Gang Logan; Fang, Nicholas X; Toussaint, Kimani C

2012-01-09

296

A directional dose equivalent monitor for neutrons.  

PubMed

A directional dose equivalent monitor is introduced which consists of a 30 cm diameter spherical phantom hosting a superheated drop detector embedded at a depth of 10 mm. The device relies on the similarity between the fluence response of neutron superheated drop detectors based on halocarbon-12 and the quality-factor-weighted kerma factor. This implies that these detectors can be used for in-phantom dosimetry and provide a direct reading of dose equivalent at depth. The directional dose equivalent monitor was characterised experimentally with fast neutron calibrations and numerically with Monte Carlo simulations. The fluence response was determined at angles of 0, 45, 90, 135 and 180 degrees for thermal to 20 MeV neutrons. The response of the device is closely proportional to the fluence-to-directional dose equivalent conversion coefficient, h'phi (10; alpha, E). Therefore, our monitor is suitable for a direct measurement of neutron directional dose equivalent, H'(10), regardless of angle and energy distribution of the neutron fluence. PMID:11548358

d'Errico, F; Alberts, W G; Curzio, G; Matzke, M; Nath, R; Siebert, B R

2001-01-01

297

TGFF: task graphs for free  

Microsoft Academic Search

We present a user-controllable, general-purpose,pseudorandom task graph generator called TaskGraphs For Free (TGFF). TGFF creates probleminstances for use in allocation and scheduling research.It has the ability to generate independenttasks as well as task sets which are composed of partiallyordered task graphs. A complete description ofa scheduling problem instance is created, includingattributes for processors, communication resources,tasks, and inter-task communication. The user...

Robert P. Dick; David L. Rhodes; Wayne Wolf

1998-01-01

298

Fishing trap with degradable cull ring panel  

US Patent & Trademark Office Database

Herein we describe crustacean fishing traps having degradable cull ring panels, as well as methods for ensuring that such traps have reduced functionality after becoming derelict. Derelict crab and lobster traps have a negative economic and ecological impact, and thus it is advantageous to use degradable traps that will lose their ability to catch and retain fish over time. Incorporating degradable cull ring panels into such traps provides an effective, economical solution. Suitable degradable cull ring panels are described herein.

2013-02-19

299

Task-specific Dystonias  

PubMed Central

Task-specific dystonias are primary focal dystonias characterized by excessive muscle contractions producing abnormal postures during selective motor activities that often involve highly skilled, repetitive movements. Historically these peculiar postures were considered psychogenic but have now been classified as forms of dystonia. Writer’s cramp is the most commonly identified task-specific dystonia and has features typical of this group of disorders. Symptoms may begin with lack of dexterity during performance of a specific motor task with increasingly abnormal posturing of the involved body part as motor activity continues. Initially, the dystonia may manifest only during the performance of the inciting task, but as the condition progresses it may also occur during other activities or even at rest. Neurological exam is usually unremarkable except for the dystonia-related abnormalities. Although the precise pathophysiology remains unclear, increasing evidence suggests reduced inhibition at different levels of the sensorimotor system. Symptomatic treatment options include oral medications, botulinum toxin injections, neurosurgical procedures, and adaptive strategies. Prognosis may vary depending upon body part involved and specific type of task affected. Further research may reveal new insights into the etiology, pathophysiology, natural history, and improved treatment of these conditions.

Torres-Russotto, Diego; Perlmutter, Joel S.

2009-01-01

300

The New Wind Chill Equivalent Temperature Chart.  

NASA Astrophysics Data System (ADS)

The formula used in the U.S. and Canada to express the combined effect of wind and low temperature on how cold it feels was changed in November 2001. Many had felt that the old formula for equivalent temperature, derived in the 1960s from Siple and Passel's flawed but quite useful Wind Chill Index, unnecessarily exaggerated the severity of the weather. The new formula is based on a mathematical model of heat flow from the upwind side of a head-sized cylinder moving at walking speed into the wind. The paper details the assumptions that were made in generating the new wind chill charts. It also points out weaknesses in the concept of wind chill equivalent temperature, including its steady-state character and a seemingly paradoxical effect of the internal thermal resistance of the cylinder on comfort and equivalent temperature. Some improvements and alternatives are suggested.

Osczevski, Randall; Bluestein, Maurice

2005-10-01

301

System Equivalent for Real Time Digital Simulator  

NASA Astrophysics Data System (ADS)

The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.

Lin, Xi

302

Entangled States of Trapped Ions  

NASA Astrophysics Data System (ADS)

Entangled states of the internal degrees of freedom are an important resource in Quantum Information Processing (QIP) and Quantum Simulation (QS) with trapped ions. Most basic requirements for QIP and QS have been demonstrated for trapped ions, with two big challenges remaining: Improving operation fidelity and scaling up to larger numbers of qubits. In the last few years, steady progress has been achieved with laser-based entanglement schemes with demonstrated fidelities of deterministically produced Bell states of 99.3% and up to 14 ion-qubits entangled in generalized GHZ-states. Scalable architectures have been proposed; one scheme, where ion-qubits are moved through a multi-zone trap array, is studied in several laboratories. Sympathetic cooling with a second ion species, which initializes the motional states for multi-qubit operations, has been demonstrated in an experiment where arbitrary operations on two qubits were implemented. Micro-fabrication approaches to ion-trap-arrays have yielded structures that should be capable of holding and manipulating large numbers of ions. Recently, with the use of microwaves, single-qubit rotations with fidelities of 99.998% per gate operation were demonstrated and two ion-qubit gates have been implemented. Microwave control could potentially be easier to scale by directly integrating microwave-lines on micro-fabricated trap devices. It also eliminates several sources of decoherence that are present in laser-based schemes by exclusively coupling to long lived hyperfine ground states.

Leibfried, Dietrich

2012-02-01

303

Quantum mechanics and the principle of equivalence  

NASA Astrophysics Data System (ADS)

Einstein's principle of equivalence is based on the notion of classical trajectories in spacetime, and the question arises of how this principle applies to quantum particles, especially those in delocalized, highly-non-classical states. I shall describe a quantum version of Galileo's classic experiment, using a model quantum clock to measure the time of flight of a quantum particle in a background gravitational field. Because the particle's mass does not scale out of Schrodinger's equation, unlike in the Newtonian case, conformity with the principle of equivalence is far from obvious and involves some interesting subtleties. It also suggests some new experiments.

Davies, Paul

2007-10-01

304

Advance task preparation reduces task error rate in the cuing task-switching paradigm  

Microsoft Academic Search

Advance preparation reduces RT task-switching cost, which is thought to be evidence of preparatory control in the cuing task-switching\\u000a paradigm. In the present study, we emphasize errors in relation to response speed. In two experiments, we show that (1) task\\u000a switching increased the rate at which the currently irrelevant task was erroneously executed (“task errors”) and (2) advance\\u000a task preparation

Nachshon Meiran; Alex Daichman

2005-01-01

305

A comparison of forgetting in an implicit and explicit memory task  

Microsoft Academic Search

Among possible critieria for distinguishing separate memory systems for implicit and explicit memory is that of substantial differences in either the form or rate of forgetting. Prior literature has claimed both differential forgetting and equivalent forgetting for implicit and explicit tasks. Existing experimental data for word-stem completion and explicit control tasks were reviewed and shown to be inconclusive. Our experiments

Dawn M. McBride; Barbara Anne Dosher

1997-01-01

306

Balkans Task Force  

NSDL National Science Digital Library

UNEP, the United Nations Environment Programme, launched the Balkans Task Force (BTF) Website on May 5, 1999 to provide information and updates on "the environmental and human settlements impacts of the ongoing Balkans conflict." Experts from the Balkans Task Force visit war-damaged (industrial) sites and post their results in a series of online Situation Reports; currently, fourteen reports (in HTML or .pdf) are available on-site. Also provided are regional maps, general information, related news and documents, and a series of links to other Websites featuring aspects of the Kosovo conflict.

307

Positron trapping at grain boundaries  

SciTech Connect

The standard positron trapping model has often been applied, as a simple approximation, to the interpretation of positron lifetime spectra in situations of diffusion-controlled trapping. This paper shows that this approximation is not sufficiently accurate, and presents a model based on the correct solution of the diffusion equation, in the version appropriate for studying positron trapping at grain boundaries. The model is used for the analysis of new experimental data on positron lifetime spectra in a fine-grained Al-Ca-Zn alloy. Previous results on similar systems are also discussed and reinterpreted. The analysis yields effective diffusion coefficients not far from the values known for the base metals of the alloys.

Dupasquier, A. (Dipartimento di Fisica del Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)); Romero, R.; Somoza, A. (Instituto de Fisica de Materiales Tandil, Facultad de Ciencias Exactas, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000 Tandil (Argentina))

1993-10-01

308

Equivalence Checking with Rule-Based Equivalence Propagation and High-Level Synthesis  

Microsoft Academic Search

Equivalence checking is one of the most important issues in VLSI designs to guarantee that bugs do not enter the design during optimization steps or synthesis steps. In this paper, we propose a new word-level equivalence checking method between two models before and after high-level synthesis or behavioral optimization. Our method converts two given designs into RTL models which have

Tasuku Nishihara; Takeshi Matsumoto; Masahiro Fujita

2006-01-01

309

A State Transformation Equivalence for Concurrent Systems: Exhibited Functionality-equivalence  

Microsoft Academic Search

Most of the equivalence notions for concurrent systems proposed in recent years are defined in terms of sequences (posets) of observable actions, and therefore they are not suitable for comparing two systems whose actions are defined at different levels of detail. In this paper a new equivalence notion for concurrent systems (more precisely for contact-free S-labelled EN systems) is introduced:

Fiorella De Cindio; Giorgio De Michelis; Lucia Pomello; Carla Simone

1988-01-01

310

Dysprosium magneto-optical traps  

NASA Astrophysics Data System (ADS)

Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high-abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs’ properties—population, temperature, loading, metastable decay dynamics, and trap dynamics—is provided.

Youn, Seo Ho; Lu, Mingwu; Ray, Ushnish; Lev, Benjamin L.

2010-10-01

311

Verifying the Reif model of MOT loading:Trap depth and density dependence  

NASA Astrophysics Data System (ADS)

We have studied the loading of rubidium atoms into a magneto-optical trap (MOT) with the aim of verifying a long-standing conjecture referred to as the Reif model. This model predicts that the loading rate should be proportional to the escape velocity of atoms from the trap to the fourth power, or equivalently, to the trap depth squared, and is directly proportional to the background rubidium atom density. The first prediction was confirmed by comparing the MOT loading rates to trap depths deduced from optical excitation of trapped atoms to a repulsive molecular potential. The rubidium density dependence was demonstrated by comparing the elastic collision-induced loss rate of atoms from a magnetic trap (MT) and the loading rate of a MOT: since the MT loss rate is proportional to the background density, the linear correlation to the MOT loading rate verified the Reif model. As a consequence of these findings, i) we have shown that the loading rates of different MOTs can be used as a convenient measure of their relative trap depths, and ii) we have experimentally determined the relationship between the capture and escape velocities in the MOTs studied (ranging in depth from 0.5 K to 1.8 K) to be vc = 1.29(0.12)ve.

Booth, James; Haw, Magnus; Evetts, Nathan; Gunton, Will; van Dongen, Janelle; Madison, Kirk

2012-06-01

312

Radiometric and equivalent isothermal surface temperatures  

Microsoft Academic Search

The analytical solution for the heat flux from an anisothermal canopy developed from K theory by Brutsaert and Sugita [1996] (hereinafter referred to as B&S) has been extended to provide a parameterization of the difference between the radiometric and the equivalent isothermal surface temperature. The latter is the isothermal temperature at which a canopy would give the correct sensible heat

Richard D. Crago

1998-01-01

313

Parametric Equivalence Scales and Scale Relativities  

Microsoft Academic Search

The authors respond to J. Banks and P. Johnson's (1994) comment on Coulter et al. (1992) drawing on a more general discussion of parametric equivalence scale and scale relativity issues and new empirical results. The authors show that criticisms of their earlier work are unfounded. When the McClements scale is properly characterized, the scale does indeed provide lower estimates of

Stephen P Jenkins; Frank A Cowell

1994-01-01

314

Biomonitoring Equivalents for DDT\\/DDE  

Microsoft Academic Search

Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline such as a reference dose (RfD) or tolerable daily intake (TDI). BE values can be used as a screening tool for the evaluation of

Christopher R. Kirman; Lesa L. Aylward; Sean M. Hays; Kannan Krishnan; Andy Nong

2011-01-01

315

Derivation of Biomonitoring Equivalents for cyfluthrin  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite

Sean M. Hays; Lesa L. Aylward; Michelle Gagné; Kannan Krishnan

2009-01-01

316

An equivalent method for blasting vibration simulation  

Microsoft Academic Search

Due to the complicated blasting load, the diversified medium models and various constitutive relations of the rock mass, and a huge job for simulating blasting of multiple holes, it is very difficult and costly to simulate the blasting vibration accurately in numerical computation. This paper presents an equivalent simulation method so as to transform this complex dynamic problem into an

Wenbo Lu; Jianhua Yang; Ming Chen; Chuangbing Zhou

2011-01-01

317

Biomonitoring Equivalents for bisphenol A (BPA)  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite

Kannan Krishnan; Michelle Gagné; Andy Nong; Lesa L. Aylward; Sean M. Hays

2010-01-01

318

Monoidal equivalence for locally compact quantum groups  

Microsoft Academic Search

In this article we investigate the notion of monoidal equivalence for locally compact quantum groups, using the notion of a (bi-)Galois object. If (M, ?) is the von Neumann algebraic realization of a locally comp act quantum group, a Galois object consists of a von Neumann algebra N together with an ergodic integrable coaction ? of M on N, such

Kenny De Commer

319

Reading adn Auditory-Visual Equivalences  

ERIC Educational Resources Information Center

|A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

Sidman, Murray

1971-01-01

320

Competitive intelligence: construct exploration, validation and equivalence  

Microsoft Academic Search

Purpose – Little empirical research has been conducted on competitive intelligence (CI). This paper aims to contribute to the quantitative strand of the CI literature by exploring and validating the theoretical constructs of the CI process. Design\\/methodology\\/approach – Data from 601 questionnaires filled out by South African and Flemish exporters were subjected to exploratory factor analysis and construct equivalence analysis

Andrea Saayman; Jaco Pienaar; Patrick de Pelsmacker; Wilma Viviers; Ludo Cuyvers; Marie-Luce Muller; Marc Jegers

2008-01-01

321

STEP (satellite test of the equivalence principle)  

Microsoft Academic Search

STEP is one of a number of missions now being developed to take advantage of the quiet space environment to carry out very sensitive gravitational experiments. Using pairs of concentric free-falling proof-masses, STEP will be able to test the equivalence principle (EP) to a sensitivity at least five orders of magnitude better than currently achievable on ground. The EP is

T. J. Sumner; J. Anderson; J.-P. Blaser; A. M. Cruise; T. Damour; H. Dittus; C. W. F. Everitt; B. Foulon; Y. Jafry; B. J. Kent; N. Lockerbie; F. Loeffler; G. Mann; J. Mester; C. Pegrum; R. Reinhardt; M. Sandford; A. Scheicher; C. C. Speake; R. Torii; S. Theil; P. Touboul; S. Vitale; W. Vodel; P. W. Worden

2007-01-01

322

Notions of equal, or equivalent, opportunities  

Microsoft Academic Search

We formulate and study three concepts of equity designed to capture certain notions of “equal”, or “equivalent”, opportunities. The central concept is that of a family of choice sets. Given such a family B, a feasible allocation z is alternatively required to be such that (i) there is B ? B such that each agent i maximizes his satisfaction in

William Thomson

1994-01-01

323

Procedures for Determining the Equivalence of Measures.  

ERIC Educational Resources Information Center

|Eight different methods are reviewed for determining whether two or more tests are equivalent measures. These methods vary in restrictiveness from the Wilks-Votaw test of compound symmetry (which requires that all means, variances, and covariances are equal), to Joreskog's theory of congeneric tests (which requires only that the tests are…

Dunivant, Noel

324

Structural equivalence of individuals in social networks  

Microsoft Academic Search

The aim of this paper is to understand the interrelations among relations within concrete social groups. Social structure is sought, not ideal types, although the latter are relevant to interrelations among relations. From a detailed social network, patterns of global relations can be extracted, within which classes of equivalently positioned individuals are delineated. The global patterns are derived algebraically through

François Lorrain; Harrison C. White

1971-01-01

325

Skin equivalent produced with human collagen.  

PubMed

Several studies have recently been conducted on cultured skin equivalent (SE), prepared using human keratinocytes seeded on various types of dermal equivalents (DE). We previously showed the advantages of our anchorage method in preventing the severe surface reduction of DE due to fibroblast contractile properties in vitro. A new anchored human SE was established in our laboratory in order to obtain a bioengineered tissue that would possess the appropriate histological and biological properties. In order to compare the effects of different collagen origins on the evolution of SE in vitro, human keratinocytes were seeded on three types of anchored DE. A comparative study was carried out between bovine SE (bSE), human SE (hSE), and human skin equivalent containing additional dermal matrix components (hSE+). Immunohistological analysis showed that hSE and hSE+ presented good structural organization, including the deposition of several basement membrane constituents. Higher amounts of transglutaminase, ceramides, and keratin 1 were detected in the epidermal layers of all SE when cultured at the air-liquid interface. However, a 92 kDa gelatinase activity was higher in bovine skin equivalent (bSE) compared to hSE cultures. The use of human collagens comparatively to bovine collagen as SE matricial component delayed the degradation of the dermal layer in culture. PMID:8589886

Auger, F A; López Valle, C A; Guignard, R; Tremblay, N; Noël, B; Goulet, F; Germain, L

1995-06-01

326

Cycle equivalence of graph dynamical systems  

NASA Astrophysics Data System (ADS)

Graph dynamical systems (GDSs) generalize concepts such as cellular automata and Boolean networks and can describe a wide range of distributed, nonlinear phenomena. Two GDSs are cycle equivalent if their periodic orbits are isomorphic as directed graphs, which captures the notion of having comparable long-term dynamics. In this paper, we study cycle equivalence of GDSs in which the vertex functions are applied sequentially through an update sequence. The main result is a general characterization of cycle equivalence based on the underlying graph Y and the update sequences. We construct and analyse two graphs C(Y) and D(Y) whose connected components contain update sequences that induce cycle equivalent dynamical system maps. The number of components in these graphs, denoted ?(Y) and ?(Y), bound the number of possible long-term behaviour that can be generated by varying the update sequence. We give a recursion relation for ?(Y) which in turn allows us to enumerate ?(Y). The components of C(Y) and D(Y) characterize dynamical neutrality, their sizes represent structural stability of periodic orbits and the number of components can be viewed as a system complexity measure. We conclude with a computational result demonstrating the impact on complexity that results when passing from radius-1 to radius-2 rules in asynchronous cellular automata.

Macauley, Matthew; Mortveit, Henning S.

2009-02-01

327

The New Wind Chill Equivalent Temperature Chart  

Microsoft Academic Search

The formula used in the U.S. and Canada to express the combined effect of wind and low temperature on how cold it feels was changed in November 2001. Many had felt that the old formula for equivalent temperature, derived in the 1960s from Siple and Passel's flawed but quite useful Wind Chill Index, unnecessarily exaggerated the severity of the weather.

Randall Osczevski; Maurice Bluestein

2005-01-01

328

Carbon Equivalence and Weldability of Microalloyed Steels.  

National Technical Information Service (NTIS)

In the final report of the effort determine the validity of carbon equivalent formulae to predict weldability of low carbon microalloyed steels, the HAZ of a range of steels was characterized (HSLA 80-130, HY 130, DQ and AC types) and the formula of Yurio...

C. D. Lundin C. Y. P. Qiao K. K. Khan T. P. S. Gill Y. Wang

1991-01-01

329

Gravity sensors and the principle of equivalence  

Microsoft Academic Search

According to the principle of equivalence, it is always possible at a point in space-time to transform to a (in general accelerated) coordinate system such that the effects of gravity will disappear over a differential region in the neighborhood of the point. Attention is given to inertial fields, the gravitational field, a differential inertial sensor, a differential gravitational sensor, the

R. L. Forward

1981-01-01

330

Antimatter gravity and the weak equivalence principle  

NASA Astrophysics Data System (ADS)

Ideas are presented for an experiment to compare the acceleration, g, of antiprotons in the Earth's gravitational field with that of particles of normed matter, such as protons or hydrogen ions. The experiments will test whether antiprotons obey the weak equivalence principle.(AIP)

Holzscheiter, M. H.; Brown, R. E.; Camp, J.; Darling, T.; Dyer, P.; Holtkamp, D. B.; Jarmie, N.; King, N. S. P.; Schauer, M. M.; Cornford, S.; Hosea, K.; Kenefick, R. A.; Midzor, M.; Oakley, D.; Ristinen, R.; Witteborn, F. C.

1991-08-01

331

AN UPDATE ON TECHNOLOGIES SEEKING PFRP EQUIVALENCY  

EPA Science Inventory

This presentation will: 1) Review the mandate of the Pathogen Equivalency Committee (PEC), 2) Review the PEC's current membership (of 10), 3) Discuss how a typical application is evaluated, 4) Note where information can be found by those interested in applying to the PEC, 5) List...

332

Equivalence of the Color Trails Test and Trail Making Test in nonnative English-speakers.  

PubMed

The Color Trails Test (CTT) has been described as a culture-fair test of visual attention, graphomotor sequencing, and effortful executive processing abilities relative to the Trail Making Test (TMT). In this study, the equivalence of the TMT and the CTT among a group of 64 bilingual Turkish university students was examined. No difference in performance on the CTT-1 and TMT Part A was found, suggesting functionally equivalent performance across both tasks. In contrast, the statistically significant differences in performance on CTT-2 and TMT Part B, as well as the interference indices for both tests, were interpreted as providing evidence for task nonequivalence of the CTT-2 and TMT Part B. Results have implications for both psychometric test development and clinical cultural neuropsychology. PMID:14590218

Dugbartey, A T; Townes, B D; Mahurin, R K

2000-07-01

333

Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging  

NASA Astrophysics Data System (ADS)

In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping.

Yao, Dezhong; He, Bin

2003-11-01

334

Method for Cognitive Task Analysis.  

National Technical Information Service (NTIS)

A method for cognitive task analysis is described based on the notion of 'generic tasks'. The method distinguishes three layers of analysis. At the first layer, the task structure, top-level goals of a certain task are identified that have to be fulfilled...

A. M. Schaafstal J. M. Schraagen

1992-01-01

335

UCLA Library Task Force  

ERIC Educational Resources Information Center

|The University of California at Los Angeles library is using part of its staff in a special mobile Task Force group to work on system-wide projects directed toward the elimination of backlogs and toward development of improved manual and automated systems. (Author)|

Nixon, Roberta

1974-01-01

336

Facilities Task Force.  

ERIC Educational Resources Information Center

|The Los Angeles Public School District is experiencing considerable overcrowding and deterioration of its public schools without adequate funding or planning to build new ones. This document presents the recommendations of a task force that assessed the district's public school crisis in the following areas: school maintenance; new facilities…

Los Angeles Unified School District, CA. School Reform Office.

337

Involuntary retrieval in alphabet-arithmetic tasks: task-mixing and task-switching costs.  

PubMed

This study explores the effects of memory retrieval in task switching. To this end, item-specific stimulus-to-task mappings were manipulated in two "alphabet-arithmetic" experiments. Letter-stimuli were presented and the responses were verbal letter names. The task was either to name the next letter in the alphabet, (e.g., C --> "D," task "plus"), or to name the preceding letter (e.g., C --> "B," task "minus"). The mapping of individual stimuli to the two tasks (and thus to responses) was either consistent (CM) or varied (VM). In Experiment 1, performance was worse for VM items relative to CM items, indicating item-specific task-mapping effects. These task-mapping effects also contributed to mixing costs (i.e., worse performance in mixed-task blocks than in pure-task blocks) but not to switch costs (worse performance in task-switch trials than in repeat trials within mixed blocks). Experiment 2 manipulated pure and mixed tasks between-participants, and the data again showed differential effects of the task-mapping manipulation on mixing costs and switch costs. This suggests that, in these memory-dependent, alphabet-arithmetic tasks, interference due to involuntary task (and/or response) retrieval primarily increases general multi-task effects, such as maintaining activation of the current task. PMID:15750868

Koch, Iring; Prinz, Wolfgang; Allport, Alan

2004-06-26

338

Microprocessor multi-task monitor  

SciTech Connect

This paper describes a multi-task monitor program for microprocessors. Although written for the Intel 8085, it incorporates features that would be beneficial for implementation in other microprocessors used in controlling and monitoring experiments and accelerators. The monitor places permanent programs (tasks) arbitrarily located throughout ROM in a priority ordered queue. The programmer is provided with the flexibility to add new tasks or modified versions of existing tasks, without having to comply with previously defined task boundaries or having to reprogram all of ROM. Scheduling of tasks is triggered by timers, outside stimuli (interrupts), or inter-task communications. Context switching time is of the order of tenths of a milllisecond.

Ludemann, C.A.

1983-01-01

339

Marshaling results of nested tasks  

US Patent & Trademark Office Database

The present invention extends to methods, systems, and computer program products for marshaling results of nested tasks. Unwrap methods are used to reduce the level of task nesting and insure that appropriate results are marshaled between tasks. A proxy task is used to represent the aggregate asynchronous operation of a wrapping task and a wrapped task. The proxy task has a completion state that is at least indicative of the completion state of the aggregate asynchronous operation. The completion state of the aggregate asynchronous operation is determined and set from one or more of the completion state of the wrapping task and the wrapped task. The completion state of the proxy task can be conveyed to calling logic to indicate the completion state of the aggregate asynchronous operation to the calling logic.

2013-03-05

340

Use of a Linear Paul Trap to Study Random Noise-Induced Beam Degradation in High-Intensity Accelerators  

NASA Astrophysics Data System (ADS)

A random noise-induced beam degradation that can affect intense beam transport over long propagation distances has been experimentally studied by making use of the transverse beam dynamics equivalence between an alternating-gradient (AG) focusing system and a linear Paul trap system. For the present studies, machine imperfections in the quadrupole focusing lattice are considered, which are emulated by adding small random noise on the voltage waveform of the quadrupole electrodes in the Paul trap. It is observed that externally driven noise continuously produces a nonthermal tail of trapped ions, and increases the transverse emittance almost linearly with the duration of the noise.

Chung, Moses; Gilson, Erik P.; Davidson, Ronald C.; Efthimion, Philip C.; Majeski, Richard

2009-04-01

341

Estimating oxide-trap, interface-trap, and border-trap charge densities in metal-oxide-semiconductor transistors  

SciTech Connect

A simple method is described that combines conventional threshold-voltage and charge-pumping measurements on [ital n]- and [ital p]-channel metal-oxide-semiconductor (MOS) transistors to estimate radiation-induced oxide-, interface-, and border-trap charge densities. In some devices, densities of border traps (near-interfacial oxide traps that exchange charge with the underlying Si) approach or exceed the density of interface traps, emphasizing the need to distinguish border-trap contributions to MOS radiation response and long-term reliability from interface-trap contributions. Estimates of border-trap charge densities obtained via this new dual-transistor technique agree well with trap densities inferred from 1/[ital f] noise measurements for transistors with varying channel length.

Fleetwood, D.M.; Shaneyfelt, M.R.; Schwank, J.R. (Sandia National Laboratories, Department 1332, Albuquerque, New Mexico 87185-1083 (United States))

1994-04-11

342

Effects of noise exposure and task demand on cardiovascular function.  

PubMed

Cardiovascular effects under various noise-exposure and task-demand conditions were studied among 40 senior highschool students. The subjects consisted of 20 males and 20 females with a mean age of 16.7 +/- 0.7 years. All subjects had equivalent abacus performance ratings. Each subject was tested with a random sequence of six sessions. The time limit set for each session was 33 min. Six experimental sessions were constructed by a random combination of noise exposure (60, 85 or 90 dB (A] white noise) and task demand (task presence or task absence) variables. Blood pressure measures were taken at the beginning and ending phases of each session. A task-demand variable was defined as a conjoint of mental arithmetic (3 min) and abacus arithmetic (30 min). The results from the present study show that the effect of noise exposure on task performance is remarkable. Only noise exposure tended to influence the performance of male students in abacus arithmetic. The effect of task demand on blood pressure was higher than that of noise exposure. No interaction effect (noise exposure x task demand) on blood pressure, was found via analyses of within-subjects two-way ANOVA. PMID:3346087

Wu, T N; Huang, J T; Chou, P F; Chang, P Y

1988-01-01

343

The cyclotron trap for antiprotons  

NASA Astrophysics Data System (ADS)

The cyclotron trap is a device to increase the stop density of negatively charged particles. Its working principle is to wind up the range of a stopping particle in a weak focusing magnetic field. Its main application in the past was the spectroscopy of exotic atoms. A modern application is the production of low energy muon or antiproton beams.

Simons, L. M.

1993-03-01

344

Ion Trapping in the Accumulator  

SciTech Connect

The beam space charge (- for {bar p}'s) will attract positive ions. In the absence of additional fields (clearing electrodes, e.g.) these ions will be trapped in the beam potential well. The depth of this potential well has been calculated for some geometries relevant for the accumulator.

Marriner, J.

1985-02-18

345

Trapped xenon in ordinary chondrites  

NASA Astrophysics Data System (ADS)

A trapped component of heavy noble gates representing a distinct solar system (presumably asteroid belt) reservoir is known to be concentrated in carbonaceous carriers of chondritic meteorites. The isotopic signature of trapped Xe in separates of the H4 chondrite Forest Vale (FV) was determined by combusting its carrier phases at 600 C in oxygen, discriminating against in situ produced nucleogenic components which are released above 600 C. The isotopic abundances of FV combustion-Xe (FVC-Xe) are compared to signatures of bulk trapped Xe in chondritic meteorites. We conclude that FVC-Xe represents the predominant trapped component in ordinary chondrites (OC) for which we adopt the term OC-Xe. Its isotopic signature differs from Xe in ureilites, in 'average carbonaceous chondrites', in earth's atmosphere, and in the solar wind. Additional minor Xe components were identified in type 3 chondrites and in the metal phase of chondrites. We discuss relationships among solar system Xe reservoirs and show that OC-Xe signature is consistent with a mixture of HL-Xe with slightly mass fractionated solar-type Xe.

Lavielle, Bernard; Marti, Kurt

1992-12-01

346

Trapped modes in coastal waveguides  

Microsoft Academic Search

Postnova and Craster (Wave Motion, 45, 2008, pp. 565–579) describe a method for determining the frequency of trapped modes in slowly-varying elastic plates, and ocean and quantum waveguides. The purpose of the present note is to show that the accuracy of the frequency estimates for ocean waveguides can be significantly increased by taking into account the fact that, as posed,

E. R. Johnson; J. T. Rodney; G. Kaoullas

347

Comparison of two American biophysics mosquito traps: the professional and a new counterflow geometry trap.  

PubMed

Large cage and field studies were conducted to compare the efficacy of 2 American Biophysics Corporation mosquito traps, the standard professional (PRO) trap and a new counterflow geometry (CFG) trap. The PRO trap utilizes conventional downdraft technology and the CFG trap uses a patent-pending technology. In large cage studies, similarly baited CFG traps captured approximately 1.7 times as many laboratory-reared Aedes taeniorhynchus as the PRO trap. The CFG trap baited with CO2 + octenol resulted in significantly reduced landing counts compared to all other treatments; mean landing count was reduced from 233.8 (12.99/min), when no trap was present, to 24.7 (1.37/min). In field studies against natural populations of woodland species, the CFG trap captured 7.8 times more mosquitoes than the PRO trap overall, and approximately 11 times more Anopheles crucians, Anopheles quadrimaculatus, and Culex erraticus. PMID:10480115

Kline, D L

1999-09-01

348

Theoretical analysis of a YBCO squirrel-cage type induction motor based on an equivalent circuit  

NASA Astrophysics Data System (ADS)

A HTS induction motor, with a HTS squirrel-cage rotor, is analysed using an electrical equivalent circuit. The squirrel-cage winding in the rotor consists of rotor bars and end rings, and both are considered to be made of YBCO film conductors. A wide range of electric field versus current density in YBCO film is formulated based on the Weibull function, and analysed as a non-linear resistance in the equivalent circuit. It is shown that starting and accelerating torques of the HTS induction motor are improved drastically compared to those of a conventional induction motor. Furthermore, large synchronous torque can also be realized by trapping the magnetic flux in the rotor circuit because of the persistent current mode.

Morita, G.; Nakamura, T.; Muta, I.

2006-06-01

349

Continuous three-dimensional radiation dosimetry in tissue-equivalent phantoms using electron paramagnetic resonance in L-alpha-alanine  

Microsoft Academic Search

A new tissue-equivalent phantom material has been developed which also acts as a dosimeter. The new phantom material has a similar elemental composition to that of soft tissue and has a density 1.1 g\\/cm³. The phantom has an agar-gel base, and contains crystallized L-..cap alpha..-alanine which traps radiation-induced free radicals. Samples from the phantom were analyzed by an electron paramagnetic

L. Wielopolski; M. Maryanski; B. Ciesielski; A. Forman; L. E. Reinstein; A. G. Meek

1987-01-01

350

Closed Magnetic Traps with Rectilinear Sections.  

National Technical Information Service (NTIS)

Aspects of plasma equilibrium and MHD stability in the Dracon closed magnetic trap which contains long rectilinear sections with a homogeneous magnetic field are discussed. Unlike racetrack stellarators, the equilibrium plasma pressure in the Dracon trap ...

V. V. Arsenin V. M. Glagolev B. B. Kadmotsev V. P. Pastukhov B. A. Trubnikov

1982-01-01

351

Nonlinear bounce kinetic equation for trapped electrons.  

National Technical Information Service (NTIS)

A nonlinear bounce averaged drift kinetic equation for trapped electrons is derived. This equation enables one to compute the nonlinear response of the trapped electron distribution function in terms of the field-line projection of a potential fluctuation...

F. Y. Gang P. H. Diamond

1990-01-01

352

Are All Wrong FCI Answers Equivalent?  

NSDL National Science Digital Library

The Force Concept Inventory (FCI) has been efficiently used to assess conceptual learning in mechanics. Each FCI question has one Newtonian answer and four wrong answers (distracters). Researchers and practitioners most frequently use measures of total score to assess learning. Yet, are all wrong answers equivalent? We conducted Latent Markov Chain Modeling (LMCM) analyses of all choices (right and wrong) on a subset of four FCI questions. LMCM assesses whether there are groups of students sharing similar patterns of responses. We infer that students sharing similar patterns also share similar reasoning. Our results show seven reasoning-groups. LMCM also computes probabilities of transition from one reasoning-group to another after instruction. Examining transitions between groups, we note a clear hierarchy. Groups at the top of the hierarchy are comprised of students that use Newtonian thinking more consistently but also choose certain wrong answers more frequently; suggesting that not all wrong answers are equivalent.

Dedic, Helena; Rosenfield, Steven; Lasry, Nathaniel

2011-01-01

353

Elements of significance testing with equivalence problems.  

PubMed

The paper outlines an approach to the general methodological problem of equivalence assessment which is based on the classical theory of testing statistical hypotheses. Within this frame of reference it is natural to search for decision rules satisfying the same criteria of optimality which are customarily applied in deriving solutions to one- and two-sided testing problems. For three standard situations very frequently encountered in medical applications of statistics, a concise account of such an optimal test for equivalence is presented. It is pointed out that tests based on the well-known principle of confidence interval inclusion are valid in the sense of guaranteeing the prespecified level of significance, but tend to have an unnecessarily low efficiency. PMID:1943791

Wellek, S; Michaelis, J

1991-08-01

354

Radiation dose equivalent to stowaways in vehicles.  

PubMed

The U.S. Bureau of Customs and Border Protection has deployed a large number of non-intrusive inspection (NII) systems at land border crossings and seaports throughout the United States to inspect cars, trucks, and sea containers. These NII systems use x rays and gamma rays for the detection of contraband. Unfortunately, undocumented aliens infrequently stow away in these same conveyances to illegally enter the United States. It is extremely important that the radiation dose equivalent imparted to these stowaways be within acceptable limits. This paper discusses the issues involved and describes a protocol the U.S. Bureau of Customs and Border Protection has used in a study to measure and document these levels. The results of this study show that the radiation dose equivalent to the stowaways from the deployed NII systems is negligibly small and does not pose a health hazard. PMID:15083143

Khan, Siraj M; Nicholas, Paul E; Terpilak, Michael S

2004-05-01

355

An Equivalent Circuit for Quantum Cascade Lasers  

NASA Astrophysics Data System (ADS)

A new simpler equivalent circuit model of a quantum cascade laser based on two level rate equations is presented. The model is valid for small and large signals. A realistic current voltage model based on experimental results is included in the circuit model. Incorporation of the current voltage characteristic makes the circuit model fully compatible with parasitics and drive electronics. The model is validated by comparison of simulated results with analytica results and large signal numerical results reported earlier.

Yong, Kelvin S. C.; Haldar, Manas K.; Webb, Jeffrey F.

2013-07-01

356

Neutron damage equivalence in GaAs  

NASA Astrophysics Data System (ADS)

A 1-MeV neutron damage equivalence methodology and damage function have been developed for GaAs based on a recoil-energy dependent damage efficiency and the displacement kerma. This method, developed using lifetime degradation in GaAs LEDs in a variety of neutron spectra, is also shown to be applicable to carrier removal. A validated methodology, such as this, is required to ensure and evaluate simulation fidelity in the neutron testing of GaAs semiconductors.

Griffin, P. J.; Kelly, J. G.; Luera, T. F.; Barry, A. L.; Lazo, M. S.

1991-12-01

357

Deciding Equivalence of Finite Tree Automata  

Microsoft Academic Search

We show:for mJe~j constant m it can be decided in polynomial time whether or not two m-ambiguous finite tree automata are equivalent. In general, inequiva- lence for finite tree automata is DEXPTIfdE-complete v).r.t, logspace reductions, and PSPACE-complete w.r.t, logspace reductions, if the automata in question are supposed to accept only finite languages. For finite tree automata uith coefficients in a

Helmut Seidl

1989-01-01

358

Equivalent networks for SAW interdigital transducers  

Microsoft Academic Search

An equivalent network approach is described for the analysis of surface-acoustic-wave interdigital transducers. Circuit parameters can he theoretically determined by applying the finite-element method to an infinite array. In this approach, all the effects of piezoelectric perturbation, mechanical perturbation, and energy storage are taken into account, To show the validity and usefulness of this approach, examples are computed for both

Kiyoshi Inagawa; Masanori Koshiba

1994-01-01

359

Observational Equivalence? Regional Studies and Regional Science  

Microsoft Academic Search

McCann P. (2007) Observational equivalence? Regional studies and regional science, Regional Studies41, 1209–1221. This paper considers the methodological and empirical issues raised by the adoption of stylized constructs in the development of regional policy. Public policies invariably require funding, and the greater levels of public data availability and press scrutiny nowadays have led to increasing requirements for policy transparency driven

Philip Mccann

2007-01-01

360

Detection of cocoa butter equivalents in chocolate  

Microsoft Academic Search

The fatty acids at the sn-2 position and the sterol composition of cocoa butter and three common cocoa butter equivalents\\u000a (CBE), namely Coberine, Choclin and Calvetta, were studied comparatively, in order to develop a sensitive method for detecting\\u000a CBE in chocolate. Differences observed in the composition of saturated fatty acids at position-sn-2 present some interest\\u000a in detecting CBE in chocolate.

D. Gegiou; K. Staphylakis

1985-01-01

361

An Equivalent Circuit for Quantum Cascade Lasers  

NASA Astrophysics Data System (ADS)

A new simpler equivalent circuit model of a quantum cascade laser based on two level rate equations is presented. The model is valid for small and large signals. A realistic current voltage model based on experimental results is included in the circuit model. Incorporation of the current voltage characteristic makes the circuit model fully compatible with parasitics and drive electronics. The model is validated by comparison of simulated results with analytica results and large signal numerical results reported earlier.

Yong, Kelvin S. C.; Haldar, Manas K.; Webb, Jeffrey F.

2013-10-01

362

Experimental study of resonance crossing with a Paul trap  

NASA Astrophysics Data System (ADS)

The effect of resonance crossing on beam stability is studied systematically by employing a novel tabletop experimental tool and a multiparticle simulation code. A large number of ions are confined in a compact linear Paul trap to reproduce the collective beam behavior. We can prove that the ion plasma in the trap is physically equivalent to a charged-particle beam propagating through a strong focusing channel. The plasma confinement force is quickly ramped such that the trap operating point traverses linear and nonlinear resonance stop bands. Assuming a nonscaling fixed field alternating gradient accelerator composed of many identical FODO cells, we measure how much ion losses occur under diverse conditions. It is experimentally and numerically demonstrated that too slow resonance crossing leads to significant ion losses as expected. Particular attention must be paid to the linear coherent resonance excited at a quarter-integer tune. When the beam intensity is high, this type of linear stop band can seriously affect the beam quality even for rather fast resonance crossing. A scaling law is given of the emittance growth caused by the quarter-integer resonance crossing.

Takeuchi, H.; Fukushima, K.; Ito, K.; Moriya, K.; Okamoto, H.; Sugimoto, H.

2012-07-01

363

Tactile function in skin-equivalent grafts.  

PubMed

Cultured grafts are excellent wound covers; however, their somatosensory capabilities are unknown. This is a preliminary report of a study which determined whether grafts of cultured skin become innervated and also examined whether seeding grafts with target tissue improved nerve growth or functional recovery. Autologous skin for grafting was generated from adult rat biopsy tissue. Dissociated keratinocytes were seeded on top of fibroblast-contracted collagen gels (skin-equivalents). Some animals received grafts composed entirely of skin-equivalents. Others had grafts with 2-mm punch biopsies (normal skin or touch domes) inserted into them. Prior to sacrifice, whole nerve recordings of the cutaneous nerves supplying the grafts were made following tactile mechanical stimulation of the graft surfaces. Tissue was processed for light and electron microscopy as well as silver stained. Nerve fibers were present in the dermis (generated from the fibroblast contracted collagen gels) of all animals and often extended to the epidermis. Light brushing of the cultured areas of the grafts produced little or no activity in the cutaneous nerves; however, afferent impulses were generated after rubbing the skin with a glass rod or pinching it with fine forceps. The implanted regions within the skin-equivalents varied from this pattern. Lightly brushing their surface resulted in vigorous activity in the nerves. Elements in the skin therefore seemed to enhance nerve regeneration and function. However, the quality of the engraftment was also important. Implanted regions of grafts experiencing poor "takes" had compromised innervation. PMID:1728555

English, K B; Stayner, N; Krueger, G; Tuckett, R P

1992-01-01

364

Water equivalence of polymer gel dosimeters  

NASA Astrophysics Data System (ADS)

To evaluate the water equivalence and radiation transport properties of polymer gel dosimeters over the wide range of photon and electron energies 14 different types of polymer gels were considered. Their water equivalence was evaluated in terms of effective atomic number (Z), electron density (?), photon mass attenuation coefficient (?/?), photon mass energy absorption coefficient (?/?) and total stopping power (S/?) of electrons using the XCOM and the ESTAR database. The study showed that the effective atomic number of polymer gels were very close (<1%) to that of water except PAGAT, MAGAT and NIPAM which had the variation of 3%, 2% and 3%, respectively. The value of ?/? and ?/? for all polymer gels were in close agreement (<1%) with that of water beyond 80 keV. The value of (S/?) of electrons in polymer gel dosimeters were within 1% agreement with that of water. From the study we conclude that at lower energy (<80keV) the polymer gel dosimeters cannot be considered water equivalent and study has to be carried out before using the polymer gel for clinical application.

Sellakumar, P.; James Jebaseelan Samuel, E.; Supe, Sanjay S.

2007-07-01

365

Semantic relatedness for evaluation of course equivalencies  

NASA Astrophysics Data System (ADS)

Semantic relatedness, or its inverse, semantic distance, measures the degree of closeness between two pieces of text determined by their meaning. Related work typically measures semantics based on a sparse knowledge base such as WordNet or Cyc that requires intensive manual efforts to build and maintain. Other work is based on a corpus such as the Brown corpus, or more recently, Wikipedia. This dissertation proposes two approaches to applying semantic relatedness to the problem of suggesting transfer course equivalencies. Two course descriptions are given as input to feed the proposed algorithms, which output a value that can be used to help determine if the courses are equivalent. The first proposed approach uses traditional knowledge sources such as WordNet and corpora for courses from multiple fields of study. The second approach uses Wikipedia, the openly-editable encyclopedia, and it focuses on courses from a technical field such as Computer Science. This work shows that it is promising to adapt semantic relatedness to the education field for matching equivalencies between transfer courses. A semantic relatedness measure using traditional knowledge sources such as WordNet performs relatively well on non-technical courses. However, due to the "knowledge acquisition bottleneck," such a resource is not ideal for technical courses, which use an extensive and growing set of technical terms. To address the problem, this work proposes a Wikipedia-based approach which is later shown to be more correlated to human judgment compared to previous work.

Yang, Beibei

366

Guide to Orifice Plate Steam Traps  

SciTech Connect

This guide was prepared to serve as a foundation for making informed decisions about when orifice plate steam traps should be considered for use in new or existing steam systems. It presents background information about different types of steam traps and defines their unique functional and operational characteristics. The advantages and disadvantages associated with using orifice plate steam traps are provided to highlight their capabilities and limitations. Finally, recommendations for using orifice plate steam traps are presented, and possible applications are identified.

Oland, C.B.

2001-01-11

367

Embodied task dynamics.  

PubMed

Movement science faces the challenge of reconciling parallel sequences of discrete behavioral goals with observed fluid, context-sensitive motion. This challenge arises with a vengeance in the speech domain, in which gestural primitives play the role of discrete goals. The task dynamic framework has proved effective in modeling the manner in which the gestural primitives of articulatory phonology can result in smooth, biologically plausible, movement of model articulators. We present a variant of the task dynamic model with 1 significant innovation: Tasks are not abstract and context free but are embodied and tied to specific effectors. An advantage of this approach is that it allows the definition of a parametric cost function that can be optimized. Optimization generates gestural scores in which the relative timing of gestures is fully specified. We demonstrate that movements generated in an optimal manner are phonetically plausible. Highly nuanced movement trajectories are emergent based on relatively simple optimality criteria. This addresses a long-standing need within this theoretical framework and provides a rich modeling foundation for subsequent work. PMID:21038977

Simko, Juraj; Cummins, Fred

2010-10-01

368

Gap Thinking in Fraction Pair Comparisons Is Not Whole Number Thinking: Is This What Early Equivalence Thinking Sounds Like?  

ERIC Educational Resources Information Center

|Gap thinking has been categorised as one of several whole number strategies that interfere with early fraction understanding. This study showed that this claim is not supported by interview data of Grade 6 students' gap thinking explanations during a fraction pair comparison task. A correlation with equivalence performance was uncovered, leading…

Mitchell, Annie; Horne, Marj

2010-01-01

369

Whatever Gave You That Idea? False Memories Following Equivalence Training: A Behavioral Account of the Misinformation Effect  

PubMed Central

The misinformation effect is a term used in the cognitive psychological literature to describe both experimental and real-world instances in which misleading information is incorporated into an account of an historical event. In many real-world situations, it is not possible to identify a distinct source of misinformation, and it appears that the witness may have inferred a false memory by integrating information from a variety of sources. In a stimulus equivalence task, a small number of trained relations between some members of a class of arbitrary stimuli result in a large number of untrained, or emergent relations, between all members of the class. Misleading information was introduced into a simple memory task between a learning phase and a recognition test by means of a match-to-sample stimulus equivalence task that included both stimuli from the original learning task and novel stimuli. At the recognition test, participants given equivalence training were more likely to misidentify patterns than those who were not given such training. The misinformation effect was distinct from the effects of prior stimulus exposure, or partial stimulus control. In summary, stimulus equivalence processes may underlie some real-world manifestations of the misinformation effect.

Challies, Danna M; Hunt, Maree; Garry, Maryanne; Harper, David N

2011-01-01

370

Sympathetic cooling of trapped Cd+ isotopes  

Microsoft Academic Search

We sympathetically cool a trapped 112Cd+ ion by directly Doppler cooling a 114Cd+ ion in the same trap. This is the first demonstration of optically addressing a single trapped ion being sympathetically cooled by a different species ion. Notably, the experiment uses a single laser source, and does not require strong focusing. This paves the way toward reducing decoherence in

B. B. Blinov; L. Deslauriers; P. Lee; M. J. Madsen; R. Miller; C. Monroe

2002-01-01

371

Improvements on a Reliable Oak Seed Trap.  

National Technical Information Service (NTIS)

The need for seed trap longevity, capture of heavy seed, and protection from predation in several forest types for long-term studies of seed production prompted seed trap design improvements. Critical improvements were achieved by painting the trap with a...

C. N. Phillips M. K. Burke T. B. Hunnicutt

1995-01-01

372

A Collapsible Trap for Capturing Ruffe  

Microsoft Academic Search

A modified version of the Windermere trap was designed, constructed, and tested for its effectiveness in capturing ruffe Gymnocephalus cernuus. The inexpensive, lightweight, collapsible trap was easily deployed and retrieved from a small boat. Field tests conducted at the St. Louis River estuary in western Lake Superior in spring 1995 and 1996 indicated that the trap was effective in capturing

Andrew J. Edwards; Gary D. Czypinski; James H. Selgeby

1998-01-01

373

Guide to Orifice Plate Steam Traps  

Microsoft Academic Search

This guide was prepared to serve as a foundation for making informed decisions about when orifice plate steam traps should be considered for use in new or existing steam systems. It presents background information about different types of steam traps and defines their unique functional and operational characteristics. The advantages and disadvantages associated with using orifice plate steam traps are

C. B. Oland

2001-01-01

374

Traps for Antimatter: The ALPHA Antihydrogen Apparatus  

Microsoft Academic Search

Antihydrogen is the simplest atomic system composed entirely of antiparticles. Analogous to hydrogen, antihydrogen contains a positron and an antiproton. The creation and storage of antihydrogen is a challenge that combines the technologies of ion trapping (nested Penning traps to accumulate and mix the positrons and antiprotons) and atom trapping (a magnetic bottle to confine the antihydrogen atoms) with the

R. Hydomako; R. I. Thompson; M. C. Fujiwara; D. R. Gill; L. Kurchaninov; K. Olchanski; A. Olin; J. W. Storey; W. N. Hardy; D. J. Jones; M. E. Hayden; H. Malik; S. Menary

2007-01-01

375

Random Walks on Lattices Containing Traps.  

National Technical Information Service (NTIS)

The paper is concerned with the trapping of random walkers on periodic lattices which contain traps. The problem which motivated this work is the motion of excitons and their trapping in photosynthetic units which are networks or lattices of chlorophyl mo...

E. W. Montroll

1969-01-01

376

Quantum teleportation with atoms trapped in cavities  

Microsoft Academic Search

We propose a scheme to implement the quantum teleportation protocol with single atoms trapped in cavities. The scheme is based on the adiabatic passage and the polarization measurement. We show that it is possible to teleport the internal state of an atom trapped in a cavity to an atom trapped in another cavity with the success probability of 1\\/2 and

Jaeyoon Cho; Hai-Woong Lee

2004-01-01

377

Laser trapping of radioactive francium atoms  

Microsoft Academic Search

The difficult problem of quickly slowing and cooling nuclear reaction products so that they can be injected into a laser trap has been solved by several groups and there are now strong efforts to work with the trapped atoms. The atoms are confined in the trap to a small spatial volume of the order of 1 mm3, but more importantly,

G. D. Sprouse; L. A. Orozco; J. E. Simsarian; W. Shi; W. Z. Zhao

1997-01-01

378

Laser trapping of radioactive francium atoms  

Microsoft Academic Search

The difficult problem of quickly slowing and cooling nuclear reaction products so that they can be injected into a laser trap has been solved by several groups and there are now strong efforts to work with the trapped atoms. The atoms are confined in the trap to a small spatial volume of the order of 1 mm3, but more importantly,

G. D. Sprouse; L. A. Orozco; J. E. Simsarian; W. Shi; W. Z. Zhao

1996-01-01

379

Enactment versus conceptual encoding: Equivalent item memory but different source memory  

PubMed Central

It has been suggested that performing a physical action (enactment) is an optimally effective encoding task, due to the incorporation of motoric information in the episodic memory trace, and later retrieval of that information. The current study contrasts old/new recognition of objects after enactment to a conceptual encoding task of cost estimation. Both encoding tasks yielded high accuracy, and robust differences in brain activity as compared to new objects, but no differences between encoding tasks. These results are not supportive of the idea that encoding by enactment leads to the spontaneous retrieval of motoric information. When participants were asked to discriminate between the two classes of studied objects during a source memory task, perform-encoded objects elicited higher accuracy and different brain activity than cost-encoded objects. The extent and nature of what was retrieved from memory thus depended on its utility for the assigned memory test: object information during the old/new recognition test, but additional information about the encoding task when necessary for a source memory test. Event-related potentials (ERPs) recorded during the two memory tests showed two orthogonal effects during an early (300-800 ms) time window: a differentiation between studied and unstudied objects, and a test-type (retrieval orientation) effect that was equivalent for old and new objects. Later brain activity (800-1300 ms) differentiated perform- from cost-encoded objects, but only during the source memory test, suggesting temporally distinct phases of retrieval.

Senkfor, Ava J.; Van Petten, Cyma; Kutas, Marta

2008-01-01

380

Traps and seals I. Structural\\/fault-seal and hydrodynamic traps  

Microsoft Academic Search

This text is a reprint of earlier papers which are part of the Treatis of Petroleum Geology. This text is part of a two volume set on oil and gas traps. The papers in these two volumes deal mainly with the mechanics of trapping hydrocarbons and with trap types. Methods of exploring for traps are discussed in another volume entitled

N. H. Foster; E. A. Beaumont

1988-01-01

381

Equivalent” Electromechanical Coefficient for IPMC Actuator Design Based on Equivalent Bimorph Beam Theory  

Microsoft Academic Search

This paper addresses an “equivalent” electromechanical coupling coefficient that may be used in designing Ionic Polymer Metal\\u000a Composite (IPMC) actuators. The coefficient is not a material constant and derived from equivalent bimorph beam model. The\\u000a collective effect of the membrane thickness and operating voltage on the coefficient is demonstrated by using a design of\\u000a experiment (DOE) of three and five

H. D. Çilingir; M. Papila

2010-01-01

382

The equivalent elastic crack: 2. X-Y equivalences and asymptotic analysis  

Microsoft Academic Search

The use of crack growth resistance curves (R-?a) to predict the behaviour of cracked specimens is a well-established practice for ceramics and materials. In Part 1 of this work, the authors showed that the use of R-?a curves may imply a certain elastic equivalence between an actual specimen governed by a cohesive crack model and a virtual equivalent linear elastic

Jaime Planas; Manuel Elices; Gonzalo Ruiz

1993-01-01

383

Testing Equivalence in Communication Research: Theory and Application  

Microsoft Academic Search

Although equivalence testing is preferred when a researcher's goal is to support the null hypothesis (i.e., no substantial effect), equivalence tests are virtually unknown and unused in the communication field. This article provides the rationale for and theoretical background of equivalence testing and offers examples of equivalence tests for the independent and dependent groups t-test and tests of association using

René Weber; Lucy Popova

2012-01-01

384

The transfer of avoidance evoking functions through stimulus equivalence classes  

Microsoft Academic Search

Recent research in the area of stimulus equivalence suggests that transfer of function via members of stimulus equivalence classes may have relevance to human emotional responding and the development and generalization of certain psychological disorders. This study investigated the transfer of avoidance evoking functions through equivalence classes. Eight subjects were trained in the necessary relations for two-four member stimulus equivalence

Erik M. Augustson; Michael J. Dougher

1997-01-01

385

Sympathetic Crystallization of Trapped Ions  

SciTech Connect

We have created multispecies Coulomb crystals in a linear Paul trap containing up to a few hundred ions of which more than 50{percent} were cooled only sympathetically through the Coulomb interaction with laser-cooled Mg{sup +} ions. In an extreme case, one laser-cooled ion maintained order in a 15thinspthinspion string. Ion species segregation was obtained by radiation pressure. Previous experiments and molecular dynamics simulations suggest the temperature is 10thinspthinspmK or lower. These results indicate that a wide range of atomic and molecular ions can be cooled and localized in linear Paul traps which is important for improvements in spectroscopic studies of such ions. {copyright} {ital 1999} {ital The American Physical Society}

Bowe, P.; Hornekaer, L.; Brodersen, C.; Drewsen, M.; Hangst, J.S. [Institute of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Schiffer, J.P. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)]|[University of Chicago, Chicago, Illinois 60637 (United States)

1999-03-01

386

Trapping and spectroscopy of hydrogen  

NASA Astrophysics Data System (ADS)

I review the results and techniques used by the MIT H? group to achieve a fractional resolution of 2 parts in 1012 in the 1S-2S transition in hydrogen [Cesar, D. Fried, T. Killian, A. Polcyn, J. Sandberg, I.A. Yu, T. Greytak, D. Kleppner and J. Doyle, Two-photon spectroscopy of trapped atomic hydrogen, Phys. Rev. Lett. 77 (1996) 255.] With some improvements, this system should deliver 100 times higher resolution with an improved signal count rate getting us closer to an old advertised goal of a precision of 1 part in 1018. While these developments are very important for the proposed test of the CPT theorem through the comparison with anti-hydrogen, some of the techniques used with hydrogen are not applicable to anti-hydrogen and I discuss some difficulties and alternatives for the trapping and spectroscopy of anti-hydrogen.

Cesar, Claudio Lenz

1997-08-01

387

Microscale ion trap mass spectrometer  

DOEpatents

An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

Ramsey, J. Michael (Knoxville, TN); Witten, William B. (Lancing, TN); Kornienko, Oleg (Lansdale, PA)

2002-01-01

388

Indirect Excitons in Elevated Traps  

NASA Astrophysics Data System (ADS)

We introduced an elevated trap technique and exploited it for lowering the effective temperature of indirect excitons. We observed narrow photoluminescence lines which correspond to the emission of individual states of indirect excitons in a disorder potential. We studied the effect of exciton-exciton interaction on the localized and delocalized exciton states and found that the homogeneous line broadening increases with density and dominates the linewidth at high densities.

High, A. A.; Hammack, A. T.; Butov, L. V.; Mouchliadis, L.; Ivanov, A. L.; Hanson, M.; Gossard, A. C.

2009-05-01

389

Optical trapping in plant cells.  

PubMed

Optical tweezers allow noninvasive manipulation of subcellular compartments to study their physical interactions and attachments. By measuring (delay of) displacements, (semi-)quantitative force measurements within a living cell can be performed. In this chapter, we provide practical tips for setting up such experiments paying special attention to the technical considerations for integrating optical tweezers into a confocal microscope. Next, we describe some working protocols to trap intracellular structures in plant cells. PMID:24132436

Ketelaar, Tijs; de Ruijter, Norbert; Niehren, Stefan

2014-01-01

390

Atom trapping with a thin magnetic film  

NASA Astrophysics Data System (ADS)

We have demonstrated trapping of neutral atoms using magnetic fields produced by a thin magnetic film. The film was magnetized in alternating north/south stripes with a 10 ?m period. The magnetizable surface used was a hard disk platter provided by Hitachi Global Storage Technologies. Tube shaped traps were created with an additional radial bias field, and the traps were loaded with atoms from a ^87Rb BEC. Radial trap frequencies of up to 20 kHz were observed. Recent results may include imaging of the individual trap sites as well as experiments with the surface as an atomic mirror.

Boyd, Micah

2005-05-01

391

Trapped torsional vibrations in elastic plates  

NASA Astrophysics Data System (ADS)

We report observation and analysis of trapped torsional vibrations in elastic plates. Each trapping element consists of a circular mesa machined in cast aluminum plate, with an electromagnetic acoustic transducer used to generate oscillatory surface traction. Suitably applied traction induced torsional vibrations trapped in the mesa. The resonant frequencies, relative displacements and Q-values were measured, and an approximate theory was developed to analyze the trapping effect with good agreement between measurements and theory. It was found that these trapped torsional modes have Q-values exceeding 100 000 with pure in-plane motion, which is of practical importance for acoustic sensor applications.

Knowles, T.; Kang, M. K.; Huang, R.

2005-11-01

392

Electrodynamic trap for neutral polar particles  

SciTech Connect

A superposition of inhomogeneous static and rapidly oscillating electric fields is capable of trapping neutral particles with a permanent electric dipole moment. Detailed numerical simulations prove the validity and stability of our trapping scheme. Thin rods of barium titanate (BaTiO{sub 3}) are presented as an example for trapping on the macroscale. HC{sub 17}N, a polar molecule of astrophysical significance, is presented as an example for trapping on the microscale. For HC{sub 17}N and the parameters chosen, the depth of the trap is 40 mK.

Bluemel, R. [Department of Physics, Wesleyan University, Middletown, Connecticut 06459-0155 (United States)

2011-04-15

393

Temperature measurements of laser trapped rubidium  

SciTech Connect

Temperatures of rubidium atoms confined in a magneto-optical trap have been measured using time-of-flight. By varying the parameters of the trap, we find that lower temperatures are obtained with lower laser intensities, larger laser detunings, lower atomic densities, and with the 85 vs. the 87 isotope. Temperatures are below the Doppler limit (140 {mu}K for Rb) in most cases. By measuring the size of the trapped cloud as well as the temperature, we can infer the spring constant of the trap. For comparison purposes, we can measure temperatures in optical molasses by turning off the magnetic field of the trap.

Dinneen, T.P.; Wallace, C.D.; Tan, K.Y.N.; Kumarakrishnan, A.; Gould, P.L.

1993-05-01

394

Nonadiabatic transitions in electrostatically trapped ammonia molecules  

SciTech Connect

Nonadiabatic transitions are known to be major loss channels for atoms in magnetic traps but have thus far not been experimentally reported upon for trapped molecules. We have observed and quantified losses due to nonadiabatic transitions for three isotopologues of ammonia in electrostatic traps by comparing the trapping times in traps with a zero and a nonzero electric field at the center. Nonadiabatic transitions are seen to dominate the overall loss rate even for the present samples that are at relatively high temperatures of 30 mK. It is anticipated that losses due to nonadiabatic transitions in electric fields are omnipresent in ongoing experiments on cold molecules.

Kirste, Moritz; Schnell, Melanie; Meijer, Gerard [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); Sartakov, Boris G. [General Physics Institute, RAS, Vavilov Street 38, 119991 Moscow (Russian Federation)

2009-05-15

395

Speckle Field As A Multiple Particle Trap  

NASA Astrophysics Data System (ADS)

We demonstrate that a speckle pattern in the spatially coherent laser field transmitted by a diffuser forms a multitude of three-dimensional bottle-shaped micro-traps. These multiple traps serve as a means for an effective trapping of large number of air-born absorbing particles. Confinement of up to a few thousand particles in air with a single beam has been achieved. Theoretical analysis of the speckle defined trapping volume and the trapping light power is in a good agreement with experimental results on capturing of aggregates of carbon nanoparticles in air.

Shvedov, V. G.; Rode, A. V.; Izdebskaya, Ya. V.; Desyatnikov, A. S.; Krolikowski, W.; Kivshar, Yu. S.

2010-10-01

396

Accretion discs trapped near corotation  

NASA Astrophysics Data System (ADS)

We show that discs accreting on to the magnetosphere of a rotating star can end up in a trapped state, in which the inner edge of the disc stays near the corotation radius, even at low and varying accretion rates. The accretion in these trapped states can be steady or cyclic; we explore these states over a wide range of parameter space. We find two distinct regions of instability: one related to the buildup and release of mass in the disc outside corotation, and the other to mass storage within the transition region near corotation. With a set of calculations over long time-scales, we show how trapped states evolve from both non-accreting and fully accreting initial conditions, and also calculate the effects of cyclic accretion on the spin evolution of the star. Observations of cycles such as found here would provide important clues on the physics of magnetospheric accretion. Recent observations of cyclic and other unusual variability in T Tauri stars (EXors) and X-ray binaries are discussed in this context.

D'Angelo, Caroline R.; Spruit, Hendrik C.

2012-02-01

397

Optical trapping inside living organisms  

NASA Astrophysics Data System (ADS)

We use optical tweezers to investigate processes happening inside ving cells. In a previous study, we trapped naturally occurring lipid granules inside living yeast cells, and used them to probe the viscoelastic properties of the cytoplasm. However, we prefer to use probes which can be specifically attached to various organelles within the living cells in order to optically quantify the forces acting on these organelles. Therefore, we have chosen to use nanometer sized gold beads as probes. These gold beads can be conjugated and attached chemically to the organelles of interest. Only Rayleigh metallic particles can be optically trapped and for these it is the case that the larger the beads, the larger the forces which can be exerted and thus measured using optical tweezers. The gold nanoparticles are injected into the cytoplasm using micropipettes. The very rigid cell wall of the S. pombe yeast cells poses a serious obstacle to this injection. In order to be able to punch a hole in the cell, first, the cells have to be turned into protoplasts, where only a lipid bilayer separates the cytoplasm from the surrounding media. We show how to perform micropipette delivery into the protoplasts and also how the protoplasts can be ablated using the trapping laserlight. Finally, we demonstrate that we can transform the protoplasts back to normal yeast cells.

Hansen, Poul M.; Oddershede, Lene B.

2005-08-01

398

Quantitative analysis of charge-carrier trapping in organic thin-film transistors from transfer characteristics  

NASA Astrophysics Data System (ADS)

A dynamic method for quantifying the amount and mechanism of trapping in organic field effect transistors (OFETs) is proposed. It exploits transfer characteristics acquired upon application of a triangular waveform gate sweep V G. The analysis of the transfer characteristics at the turning point V G=- V max between forward and backward gate sweeps, viz. around the maximum gate voltage V max applied, provides a differential slope ? m which depends exclusively on trapping. Upon a systematic change of V max it is possible to extract the initial threshold voltage, equivalent to one of the observables of conventional stress measurements, and assess the mechanism of trapping via the functional dependence on the current. The analysis of the differential logarithmic derivative at the turning point yields the parameters of trapping, as the exponent ? and the time scale of trapping ?. In the case of an ultra-thin pentacene OFET we extract ?=1 and ?=102-103 s, in agreement with an exponential distribution of traps. The analysis of the hysteresis parameter ? m is completely general and explores time scales much shorter than those involved in bias stress measurements, thus avoiding irreversible damage to the device.

D'Angelo, Pasquale; Stoliar, Pablo; Cramer, Tobias; Cassinese, Antonio; Zerbetto, Francesco; Biscarini, Fabio

2009-04-01

399

Equivalent solder joint and equivalent layer models for the simulation of solder column failure under drop impact  

Microsoft Academic Search

We provide two new equivalent global models - equivalent solder joint model and equivalent layer model - to perform the simulation of solder joints under drop impact. A detailed global model with a fine mesh is used as a benchmark to control the accuracy of the simplified equivalent model. Excellent correlation has been achieved in these two models, when compared

Gu Jie; C. T. Lim; A. A. O. Tay

2004-01-01

400

Stem Cell Task Force  

NSDL National Science Digital Library

This Web site from the National Institutes of Health (NIH) provides an overview of the activities of an NIH task force established to move the stem cell research agenda forward. The section titled Scientific Research may be of particular interest to researchers in this area. It provides links to the Web sites of stem cell-related research at a number of NIH institutes, as well as an extensive information index, a FAQs page about stem cell research, information on funding opportunities, and much more.

401

All steam traps are not equal  

SciTech Connect

Proper selection of a steam trap will result in a long-lasting, trouble-free steam distribution system. The definition of a trap is simple enough: it should get rid of air and purge off noncondensibles when the system is started up and drain condensate anytime during operation. This is the reason traps are sometimes called automatic drain valves. A steam trap should not discharge live steam because that wastes energy and money. Steam traps are a basic requirement on a steam line, but not just any one will do. Steam systems and services differ, and so do the traps that serve them, but well-selected steam traps can do a fine job. For example, the thermal element type traps can quickly remove condensate, work in a wide range of pressure and capacity, help avoid water hammer, control corrosion by removing noncondensibles and require little maintenance. To help specify the optimum steam trap for particular service conditions and manner of operation, it is important to understand major steam trap types, with an eye to the services each one is best suited for and required maintenance. Some of the more common types of steam traps include: inverted bucket; float and thermostatic (F and T); thermodynamic or disc; bimetallic thermostatic; and thermal-element thermostatic. The different types are described and compared.

Alesson, T. [Watson McDaniel Co., Norristown, PA (United States)

1995-08-01

402

Testing efficiency transfer codes for equivalence.  

PubMed

Four general Monte Carlo codes (GEANT3, PENELOPE, MCNP and EGS4) and five dedicated packages for efficiency determination in gamma-ray spectrometry (ANGLE, DETEFF, GESPECOR, ETNA and EFFTRAN) were checked for equivalence by applying them to the calculation of efficiency transfer (ET) factors for a set of well-defined sample parameters, detector parameters and energies typically encountered in environmental radioactivity measurements. The differences between the results of the different codes never exceeded a few percent and were lower than 2% in the majority of cases. PMID:19892558

Vidmar, T; Celik, N; Cornejo Díaz, N; Dlabac, A; Ewa, I O B; Carrazana González, J A; Hult, M; Jovanovi?, S; Lépy, M-C; Mihaljevi?, N; Sima, O; Tzika, F; Jurado Vargas, M; Vasilopoulou, T; Vidmar, G

2009-10-17

403

Equivalent topological invariants of topological insulators  

NASA Astrophysics Data System (ADS)

A time-reversal (TR) invariant topological insulator can be generally defined by the effective topological field theory with a quantized ? coefficient, which can only take values of 0 or ?. This theory is generally valid for an arbitrarily interacting system and the quantization of the ? invariant can be directly measured experimentally. Reduced to the case of a non-interacting system, the ? invariant can be expressed as an integral over the entire three-dimensional Brillouin zone. Alternatively, non-interacting insulators can be classified by topological invariants defined over discrete TR invariant momenta. In this paper, we show the complete equivalence between the integral and the discrete invariants of the topological insulator.

Wang, Zhong; Qi, Xiao-Liang; Zhang, Shou-Cheng

2010-06-01

404

Equivalent mass of a coil spring  

NASA Astrophysics Data System (ADS)

The Hooke's law force on a coil spring often constitutes a student's first introduction to the properties of simple harmonic motion. The usual treatment assumes a vertical massless spring, held fixed at one end and stretched by a hanging mass M at the other. An occasional text, however, points out that the treatment, in the case of a hanging spring, can be improved by taking into account the equivalent mass mo/3 of the spring. It is only necessary to addmo/3 to the hanging mass M in the expression that relates the frequency of the spring oscillations to M and to the spring constant k.

Ruby, Lawrence

2000-03-01

405

Evaluation of trapping-web designs  

USGS Publications Warehouse

The trapping web is a method for estimating the density and abundance of animal populations. A Monte Carlo simulation study is performed to explore performance of the trapping web for estimating animal density under a variety of web designs and animal behaviours. The trapping performs well when animals have home ranges, even if the home ranges are large relative to trap spacing. Webs should contain at least 90 traps. Trapping should continue for 5-7 occasions. Movement rates have little impact on density estimates when animals are confined to home ranges. Estimation is poor when animals do not have home ranges and movement rates are rapid. The trapping web is useful for estimating the density of animals that are hard to detect and occur at potentially low densities. ?? CSIRO 2005.

Lukacs, P. M.; Anderson, D. R.; Burnham, K. P.

2005-01-01

406

TASK: Let's Have a Party!  

ERIC Educational Resources Information Center

In this article, the author describes a creative way to demystify contemporary art for students. TASK is artist Oliver Herring's creation, where participants actively interpret instructions found on little pieces of paper--what he calls "tasks." An art classroom has all the key ingredients for a TASK event: (1) people; (2) materials; (3) space;…

Rees, James

2012-01-01

407

Task Compatibility of Manipulator Postures  

Microsoft Academic Search

Inperforming a manipulation task, humans tend to adopt arm postures that most effectively utilize the motion and strength capabilities of the arm. Selecting arm postures that are compatible with the task requirements has become almost instinctive to humans. By mimicking this approach in robotic manipulation, we can exploit the full capability of a manipu lator in performing a task. An

Stephen L. Chiu

1988-01-01

408

Task-oriented rehabilitation robotics.  

PubMed

Task-oriented training is emerging as the dominant and most effective approach to motor rehabilitation of upper extremity function after stroke. Here, the authors propose that the task-oriented training framework provides an evidence-based blueprint for the design of task-oriented robots for the rehabilitation of upper extremity function in the form of three design principles: skill acquisition of functional tasks, active participation training, and individualized adaptive training. The previous robotic systems that incorporate elements of task-oriented trainings are then reviewed. Finally, the authors critically analyze their own attempt to design and test the feasibility of a TOR robot, ADAPT (Adaptive and Automatic Presentation of Tasks), which incorporates the three design principles. Because of its task-oriented training-based design, ADAPT departs from most other current rehabilitation robotic systems: it presents realistic functional tasks in which the task goal is constantly adapted, so that the individual actively performs doable but challenging tasks without physical assistance. To maximize efficacy for a large clinical population, the authors propose that future task-oriented robots need to incorporate yet-to-be developed adaptive task presentation algorithms that emphasize acquisition of fine motor coordination skills while minimizing compensatory movements. PMID:23080042

Schweighofer, Nicolas; Choi, Younggeun; Winstein, Carolee; Gordon, James

2012-11-01

409

The transfer of contextual control over equivalence classes through equivalence classes: a possible model of social stereotyping.  

PubMed Central

In Experiment 1, subjects acquired conditional equivalence classes controlled by three male and three female names as contextual stimuli. When equivalence relations were tested using new names not used in training (three male and three female), contextual control remained intact. Thus, generalized control of the composition of conditional equivalence classes by characteristically gender-identified names was shown. A basic analysis of this finding was tested in Experiment 2. Contextual equivalence classes were established using as contextual stimuli nonrepresentational visual figures that were members of additional pretrained three-member equivalence classes. When other stimuli in the pretrained equivalence classes were used as contextual stimuli, the conditional equivalence classes remained intact. Control subjects showed that this effect depended on the equivalence relations established in pretraining. The results show that contextual control over equivalence classes can transfer through equivalence classes. The implications of this phenomenon for social stereotyping are discussed.

Kohlenberg, B S; Hayes, S C; Hayes, L J

1991-01-01

410

Solar Energetic Particles Trapping in the Magnetosphere  

NASA Astrophysics Data System (ADS)

Solar energetic particles (SEPs) are protons, electrons, and heavy ions emitted from the Sun with energies spanning tens of keV to GeV. They are episodic and associated with energetic events at the Sun such as coronal mass ejections. Importantly, they can be injected into and trapped by the Earth's magnetosphere, forming transient new, intense radiation belts that can severely damage components of our space infrastructure and cause significant backgrounds in instruments on national security and other payloads. Our goal is to understand the conditions under which SEPs become trapped and untrapped in the magnetosphere, how trapping depends on the energy distribution of the trapped particles, and if we can predict the location and persistence of these new radiation belts. Previous studies have shown how trapping can occur for individual shock-driven events but do not explore the overall magnetospheric conditions that can lead to SEP trapping and cannot predict trapped population energy spectra, location, or provide a probabilistic model trapping likelihood. Using events spanning 10 years, we will correlate the magnetospheric conditions that affect trapping and dumping. The results of this study will attempt to answer the questions: What fraction of injected SEPs are trapped,forming new, persistent radiation belts? Is there a geomagnetic field preconditioning required for injected SEPs to be trapped or untrapped? What does the energy distribution of injected SEPs relative to their trapped distribution tell us about the underlying physics of trapping? What is the probability of trapping injected SEPs based on different magnetospheric conditions, and can we use this probability as a predictive tool?

Engel, M.; Larsen, B. A.

2011-12-01

411

The Traps of Formal Correspondence.  

ERIC Educational Resources Information Center

|The dangers of translation are discussed when the translator does not try to create textual equivalence, but settles for formal correspondence (i.e., with simple transcoding at a linguistic level) during the process of translating. Difficulties of explaining, commenting, or summarizing rather than translating are also discussed. Pedagogical and…

Albert, Sandor

412

Effects of noise exposure and task demand on cardiovascular function  

Microsoft Academic Search

Cardiovascular effects under various noise-exposure and task-demand conditions were studied among 40 senior highschool students. The subjects consisted of 20 males and 20 females with a mean age of 16.7 ± 0.7 years. All subjects had equivalent abacus performance ratings. Each subject was tested with a random sequence of six sessions. The time limit set for each session was 33

Trong-Neng Wu; Jong-Tsun Huang; Peter F. S. Chou; Po-Ya Chang

1988-01-01

413

Structural analysis of artificial skin equivalents  

NASA Astrophysics Data System (ADS)

Artificial skin equivalents ASEs based on primary fibroblasts and keratinocytes show a high batch variance in their structural and morphological characteristics. Due to biological fluctuations and variable donor age, the growth processes of 3D tissue structure show a non constant quality. Since theses ASEs are used as testing system for chemicals, pharmaceuticals or cosmetics it is of major interest to know detailed and significant characteristics about each individual ASE. Until now, the microscopic analysis process is based on the destructive preparation of histologies allowing only the characterization on a random basis. In this study we present analytical methods to characterise each individual ASE by Optical Coherence Tomography OCT in combination with image processing tools. Therefore, we developed a fully automated OCT device, that performs automatic measurements of microtiter plates MTPs holing the ASEs in a sterile environment. We developed image processing algorithms to characterize the surface structure which may function as an indicator for defects in the epidermal stratum corneum. Further, we analysed the tomographic morphological structure of the ASEs. The results show, that variances in the growth state as well different collagen formation is detectable. In combination with dynamic threshold levels, we found, that OCT is a well suited technology for automatically characterizing artificial skin equivalents and may partly substitute the preparation of histologies.

Schmitt, Robert; Marx, Ulrich; Walles, Heike; Schober, Lena

2011-06-01

414

Equivalence between microcanonical ensembles for lattice models  

NASA Astrophysics Data System (ADS)

The development of reliable methods for estimating microcanonical averages constitutes an important issue in statistical mechanics. One possibility consists of calculating a given microcanonical quantity by means of typical relations in the grand-canonical ensemble. But given that distinct ensembles are equivalent only at the thermodynamic limit, a natural question is if finite size effects would prevent such a procedure. In this work we investigate thoroughly this query in different systems yielding first- and second-order phase transitions. Our study is carried out from the direct comparison with the thermodynamic relation (?s?e), where the entropy s is obtained from the density of states and e is the energy per site. A systematic analysis for finite sizes is undertaken. We find that, although results become inequivalent for extremely low system sizes, the equivalence holds true for rather small L’s. Therefore direct, simple (when compared with other well established approaches) and very precise microcanonical quantities can be obtained from the proposed method.

Fiore, Carlos E.; DaSilva, Cláudio J.

2013-05-01

415

Equivalence of trans paths in ion channels  

NASA Astrophysics Data System (ADS)

We explore stochastic models for the study of ion transport in biological cells. Analysis of these models explains and explores an interesting feature of ion transport observed by biophysicists. Namely, the average time it takes ions to cross certain ion channels is the same in either direction, even if there is an electric potential difference across the channels. It is shown for simple single ion models that the distribution of a path (i.e., the history of location versus time) of an ion crossing the channel in one direction has the same distribution as the time-reversed path of an ion crossing the channel in the reverse direction. Therefore, not only is the mean duration of these paths equal, but other measures, such as the variance of passage time or the mean time a path spends within a specified section of the channel, are also the same for both directions of traversal. The feature is also explored for channels with interacting ions. If a system of interacting ions is in reversible equilibrium (net flux is zero), then the equivalence of the left-to-right trans paths with the time-reversed right-to-left trans paths still holds. However, if the system is in equilibrium, but not reversible equilibrium, then such equivalence need not hold.

Alvarez, Juan; Hajek, Bruce

2006-04-01

416

SCHEDULING IMPRECISE COMPUTATION TASKS WITH INTRA-TASK \\/ INTER-TASK DEPENDENCE  

Microsoft Academic Search

This work presents two heuristics to be used as admission policy in imprecise task systems. It is assumed that imprecise tasks have intra-task and inter-task dependence and a 0\\/1 constraint. These heuristics are supposed to be used combined with off-line schedulability tests and on-line acceptance tests already described in the literature. The objective of the admission policy is to maximize

R. S. Oliveira; J. S. Fraga

1996-01-01

417

Random walks in weighted networks with a perfect trap: An application of Laplacian spectra  

NASA Astrophysics Data System (ADS)

Trapping processes constitute a primary problem of random walks, which characterize various other dynamical processes taking place on networks. Most previous works focused on the case of binary networks, while there is much less related research about weighted networks. In this paper, we propose a general framework for the trapping problem on a weighted network with a perfect trap fixed at an arbitrary node. By utilizing the spectral graph theory, we provide an exact formula for mean first-passage time (MFPT) from one node to another, based on which we deduce an explicit expression for average trapping time (ATT) in terms of the eigenvalues and eigenvectors of the Laplacian matrix associated with the weighted graph, where ATT is the average of MFPTs to the trap over all source nodes. We then further derive a sharp lower bound for the ATT in terms of only the local information of the trap node, which can be obtained in some graphs. Moreover, we deduce the ATT when the trap is distributed uniformly in the whole network. Our results show that network weights play a significant role in the trapping process. To apply our framework, we use the obtained formulas to study random walks on two specific networks: trapping in weighted uncorrelated networks with a deep trap, the weights of which are characterized by a parameter, and Lévy random walks in a connected binary network with a trap distributed uniformly, which can be looked on as random walks on a weighted network. For weighted uncorrelated networks we show that the ATT to any target node depends on the weight parameter, that is, the ATT to any node can change drastically by modifying the parameter, a phenomenon that is in contrast to that for trapping in binary networks. For Lévy random walks in any connected network, by using their equivalence to random walks on a weighted complete network, we obtain the optimal exponent characterizing Lévy random walks, which have the minimal average of ATTs taken over all target nodes.

Lin, Yuan; Zhang, Zhongzhi

2013-06-01

418

The role of task preparation and task inhibition in age-related task-switching deficits.  

PubMed

The aim of our study was to examine the role of task preparation and task inhibition in age-related task-switching deficits. In 2 experiments, we used a cuing paradigm with 3 tasks and manipulated the cue-stimulus interval (CSI). Additionally, switching among 3 tasks enabled us to examine n-2 task repetition costs, which reflect persisting inhibition of abandoned tasks. In Experiment 1, we found larger mixing costs (i.e., performance in mixed-task blocks vs. single-task blocks) in older adults than in young adults, and preparation effects were smaller in older adults than in young adults. In Experiment 2, where CSIs were blocked instead of randomly varied, we replicated reduced effects of task preparation in older adults. N-2 task repetition costs were not significant in Experiment 1 but significant in Experiment 2, and these costs did not differ across age groups in both experiments. The data suggest a task-preparation deficit in older adults that contributes to increased mixing costs in older adults. PMID:22468851

Lawo, Vera; Philipp, Andrea M; Schuch, Stefanie; Koch, Iring

2012-04-02

419

Task success, task popularity, and self-esteem as influences on task liking  

Microsoft Academic Search

Reports 3 experiments which support the hypothesis that there is a positive relationship between task success and task satisfaction for persons who hold themselves in high self-esteem but not for those whose self-esteem is low. Implications for a general theory of job satisfaction influenced by personal and task variables are discussed. (15 ref.)

Abraham K. Korman

1968-01-01

420

The Composite Insect Trap: An Innovative Combination Trap for Biologically Diverse Sampling  

PubMed Central

Documentation of insect diversity is an important component of the study of biodiversity, community dynamics, and global change. Accurate identification of insects usually requires catching individuals for close inspection. However, because insects are so diverse, most trapping methods are specifically tailored to a particular taxonomic group. For scientists interested in the broadest possible spectrum of insect taxa, whether for long term monitoring of an ecosystem or for a species inventory, the use of several different trapping methods is usually necessary. We describe a novel composite method for capturing a diverse spectrum of insect taxa. The Composite Insect Trap incorporates elements from four different existing trapping methods: the cone trap, malaise trap, pan trap, and flight intercept trap. It is affordable, resistant, easy to assemble and disassemble, and collects a wide variety of insect taxa. Here we describe the design, construction, and effectiveness of the Composite Insect Trap tested during a study of insect diversity. The trap catches a broad array of insects and can eliminate the need to use multiple trap types in biodiversity studies. We propose that the Composite Insect Trap is a useful addition to the trapping methods currently available to ecologists and will be extremely effective for monitoring community level dynamics, biodiversity assessment, and conservation and restoration work. In addition, the Composite Insect Trap will be of use to other insect specialists, such as taxonomists, that are interested in describing the insect taxa in a given area.

Russo, Laura; Stehouwer, Rachel; Heberling, Jacob Mason; Shea, Katriona

2011-01-01

421

A family of exact eigenstates for a single trapped ion interacting with a laser field  

NASA Astrophysics Data System (ADS)

We show that, under certain combinations of the parameters governing the interaction of a harmonically trapped ion with a laser beam, it is possible to find one or more exact eigenstates of the Hamiltonian, with no approximations except the optical rotating-wave approximation. These are related via a unitary equivalence to exact eigenstates of the full Jaynes-Cummings model (including counter-rotating terms) supplemented by a static driving term.

Moya-Cessa, H.; Jonathan, D.; Knight, P. L.

2003-02-01

422

Motional macroscopic quantum superposition states of a trapped three-level ion  

Microsoft Academic Search

We investigate quantum dynamical properties of a trapped three-level ion interacting with two laser beams in λ configuration. A unitary transformation method is developed to study the interaction of the ion with its vibrational phonons, quanta of ion's own center-of-mass motion. Under certain conditions on laser parameters, this interaction is shown to be unitarily equivalent to two-phonon cascade transitions. Complicated

Muestecaplioglu; Oe. E

2003-01-01

423

Motional macroscopic quantum superposition states of a trapped three-level ion  

Microsoft Academic Search

We investigate quantum dynamical properties of a trapped three-level ion interacting with two laser beams in Lambda configuration. A unitary transformation method is developed to study the interaction of the ion with its vibrational phonons, quanta of ion's own center-of-mass motion. Under certain conditions on laser parameters, this interaction is shown to be unitarily equivalent to two-phonon cascade transitions. Complicated

Ö. E. Müstecaplioglu

2003-01-01

424

Trapped magnetic flux in superconducting niobium samples  

NASA Astrophysics Data System (ADS)

Trapped magnetic flux is known to be one cause of residual losses in bulk niobium superconducting radio frequency cavities. In the Meissner state an ambient magnetic field should be expelled from the material. Disturbances such as lattice defects or impurities have the ability to inhibit the expulsion of an external field during the superconducting transition so that the field is trapped. We have investigated the effect the treatment history of bulk niobium has on the trapped flux and which treatment leads to minimal flux trapping. For that purpose, we measured the fraction of trapped magnetic flux in niobium samples representing cavities with different typical treatment histories. The differences between single crystal and polycrystalline material as well as the influence of spatial temperature gradients and different cooling rates were investigated. In addition, the progression of the release of a trapped field during warm-up was studied. We found that heat treatment reduces trapped flux considerably and that single crystal samples trap less flux than polycrystalline niobium. As a consequence, the single crystal sample with 1200°C baking trapped the smallest amount of field which is about 42%. Moreover, the release of the trapped field during warm-up was observed to progress over a broad temperature range for the baked single crystal samples.

Aull, S.; Kugeler, O.; Knobloch, J.

2012-06-01

425

Scenario-Based Tasks  

NSDL National Science Digital Library

This page from The Experiential Learning Center provides a number of scenario-based tasks for use in the classroom or for professional development training. The materials are freely available for download and use and would be applicable to learners in a variety of subjects including software development, faculty professional development, office system applications/ICT, biology/bioinformatics, environmental studies, Python programming, engineering, network security/MIS, computational thinking and English writing. Instructor guides and other classroom instructional materials are provided. The project requests that educators let them know when these materials are used in order to track dissemination of the work and in order to inform the community about upcoming workshops and presentations.

2012-10-09

426

Portable Pbars, traps that travel  

SciTech Connect

The advent of antiproton research utilizing relatively small scale storage devices for very large numbers of these particles opens the possibility of transporting these devices to a research site removed from the accelerator center that produced the antiprotons. Such a portable source of antiprotons could open many new areas of research and make antiprotons available to a new research community. At present antiprotons are available at energies down to 1 MeV. From a portable source these particles can be made available at energies ranging from several tens of kilovolts down to a few millielectron volts. These low energies are in the domain of interest to the atomic and condensed matter physicist. In addition such a source can be used as an injector for an accelerator which could increase the energy domain even further. Moreover, the availability of such a source at a university will open research with antiprotons to a broader range of students than possible at a centralized research facility. This report focuses on the use of ion traps, in particular cylindrical traps, for the antiproton storage device. These devices store the charged antiprotons in a combination of electric and magnet fields. At high enough density and low enough temperature the charged cloud will be susceptible to plasma instabilities. Present day ion trap work is just starting to explore this domain. Our assessment of feasibility is based on what could be done with present day technology and what future technology could achieve. We conclude our report with a radiation safety study that shows that about 10/sup 11/ antiprotons can be transported safely, however the federal guidelines for this transport must be reviewed in detail. More antiprotons than this will require special transportation arrangements. 28 refs., 8 figs.

Howe, S.D.; Hynes, M.V.; Picklesimer, A.

1987-10-01

427

Optimizing the optical trapping stiffness of holographically trapped microrods using high-speed video tracking  

NASA Astrophysics Data System (ADS)

Dielectric microrods can be trapped horizontally in pairs of holographically controlled optical traps. External forces acting on these microrods are registered via the rotational and translational displacement of the microrod relative to the traps. In the following paper we demonstrate accurate, real-time tracking of this displacement in two dimensions. The precision of the method is estimated and the translational and rotational stiffness coefficients of the trapped microrod are evaluated by analysing the thermal motion and the Stokes drag. The variation of these stiffness coefficients relative to the displacement of the traps from the ends of the microrods is measured, and optimal trapping conditions are located.

Phillips, D. B.; Carberry, D. M.; Simpson, S. H.; Schäfer, H.; Steinhart, M.; Bowman, R.; Gibson, G. M.; Padgett, M. J.; Hanna, S.; Miles, M. J.

2011-04-01

428

Cosmological apparent and trapping horizons  

NASA Astrophysics Data System (ADS)

The dynamics of particle, event, and apparent horizons in Friedmann-Lemaitre-Robertson-Walker space are discussed. The apparent horizon is trapping when the Ricci curvature is positive. This simple criterion coincides with the condition for the Kodama-Hayward apparent horizon temperature to be positive and also discriminates between the timelike and spacelike character of the apparent horizon. We discuss also the entropy of apparent cosmological horizons in extended theories of gravity and we use the generalized 2nd law to discard an exact solution of Brans-Dicke gravity as unphysical.

Faraoni, Valerio

2011-07-01

429

Radiation Belts and Trapped Particles  

NSDL National Science Digital Library

This tutorial introduces students to Earth's radiation belts, also known as the Van Allen Belts after their discoverer. Topics include the structure of the radiation belts and the currents of particles trapped in Earth's magnetic fields, their properties, and where they come from. There is also a set of classroom activities for exploring radiation belts and solar storms and a set of illustrations and movies of the belts. Other materials include news items related to the radiation belts, recordings of 'space sounds' related to the influence of lightning on Earth's magnetic field, and a frequently-asked-questions feature.

430

Unconscious task set priming with phonological and semantic tasks.  

PubMed

Whether unconscious stimuli can modulate the preparation of a cognitive task is still controversial. Using a backward masking paradigm, we investigated whether the modulation could be observed even if the prime was made unconscious in 100% of the trials. In two behavioral experiments, subjects were instructed to initiate a phonological or semantic task on an upcoming word, following an explicit instruction and an unconscious prime. When the SOA between prime and instruction was sufficiently long (84 ms), primes congruent with the task set instruction led to speedier responses than incongruent primes. In the other condition (36 ms), no task set priming was observed. Repetition priming had the opposite tendency, suggesting the observed task set facilitation cannot be ascribed solely to perceptual repetition priming. Our results therefore confirm that unconscious information can modulate cognitive control for currently active task sets, providing sufficient time is available before the conscious decision. PMID:23558083

Weibel, Sébastien; Giersch, Anne; Dehaene, Stanislas; Huron, Caroline

2013-04-02

431

Equivalent transformation for a partially adaptive array  

NASA Astrophysics Data System (ADS)

A partially adaptive array (PAA) is one in which elements of a phased array are controlled or adaptively weighted in groups or in which auxiliary elements are made controllable. A PAA is formed by transforming all of the elements by a nonsquare matrix such that the resulting output vector has a length less than the number of elements. It is shown that there is an equivalent matrix transform that can be used to analyze PAA performance when a small number of external jammers are present. To measure canceller performance, the optimal output SNR is computed as a function of the jammer direction-of-arrival vectors (DOAVs), jammer powers, the array steering vector, and internal noise. This expression is easily computed for the PAA by transforming the jammer DOAVs and the steering vector by the orthogonal projection matrix defined by the rows of the subarray transformation matrix and substituting these vectors back into the original expression for the fully adaptive array.

Gerlach, Karl

1990-11-01

432

Noise-equivalent sensitivity of photoacoustics.  

PubMed

The fundamental limitations of photoacoustic microscopy for detecting optically absorbing molecules are investigated both theoretically and experimentally. We experimentally demonstrate noise-equivalent detection sensitivities of 160,000 methylene blue molecules (270 zeptomol or 2.7×10-19??mol) and 86,000 oxygenated hemoglobin molecules (140 zeptomol) using narrowband continuous-wave photoacoustics. The ultimate sensitivity of photoacoustics is fundamentally limited by thermal noise, which can present in the acoustic detection system as well as in the medium itself. Under the optimized conditions described herein and using commercially available detectors, photoacoustic microscopy can detect as few as 100s of oxygenated hemoglobin molecules. Realizable improvements to the detector may enable single molecule detection of select molecules. PMID:24026425

Winkler, Amy M; Maslov, Konstantin; Wang, Lihong V

2013-09-01

433

Biomonitoring Equivalents (BE) dossier for trihalomethanes.  

PubMed

Measurements of whole blood concentrations of trihalomethanes (THMs) have been reported in persons in the general population. Risk assessments based on administered doses of THMs have been conducted for both cancer and non-cancer health endpoints by the US Environmental Protection Agency; however, no health-based standards exist for interpreting measured blood concentrations of THMs. Existing physiologically based pharmacokinetic models for laboratory rats, dogs, and humans were used to estimate the average blood concentrations consistent with the points of departure, reference doses (RfDs), and, where applicable, cancer potency estimates to provide biomonitoring equivalents (BEs) for these exposure guidance values. The models were also used to characterize the short term variations in blood concentrations that could result from various exposure regimens, even when exposures remain consistent with the underlying RfDs. The BE values derived in this exercise can be used as one component of a screening-level assessment of future population biomonitoring THM data. PMID:18579267

Aylward, Lesa L; LaKind, Judy S; Hays, Sean M

2008-05-22

434

Characterization of dextrins with different Dextrose Equivalents.  

PubMed

Dextrins are widely used for their functional properties and prepared by partial hydrolysis of starch using acid, enzymes, or combinations of both. The physiochemical properties of dextrins are dependent on their molecular distribution and oligosaccharide profiles. In this study, scanning electron microscopy (SEM), X-ray diffractometry (XRD), rapid viscoanalysis (RVA), high-performance Liquid Chromatography (HPLC) and gel permeation chromatography (GPC) were used to characterize dextrins prepared by common neutral and thermostable alpha-amylase hydrolysis. The dextrin granules displayed irregular surfaces and were badly damaged by the enzyme treatment. They displayed A-type X-ray diffraction patterns with a decrease of intensity of the characteristic diffraction peaks. The RVA profiles showed that the viscosity of dextrin decreased with the increase of its Dextrose Equivalent (DE) value. According to HPLC analysis, the molecular weight, degree of polymerization and the composition of oligosaccharides in dextrins were different. PMID:20714293

Sun, Junliang; Zhao, Ruixiang; Zeng, Jie; Li, Guanglei; Li, Xinhua

2010-07-29

435

Charge Propagation Dynamics in Temperature Quenching of Sm-Doped TiO2: Impedance Spectroscopy of Release Processes of Trapped Charges Determining Luminescence Intensity  

NASA Astrophysics Data System (ADS)

The mechanism of the temperature quenching of luminescence in samarium-doped titanium dioxide (TiO2:Sm) was investigated with electrical measurement techniques. Because electrical measurements are sensitive to charge dynamics, the indirect excitation processes of the Sm dopants, i.e., trapping and recombination of injected charges into the host TiO2, can be clarified. Complex impedance spectroscopy between 100 and 300 K revealed a correlation between the temperature quenching of TiO2:Sm and the trapping and recombination processes. Analyses using equivalent circuits revealed that the main factor determining the temperature quenching properties was delocalization of the trapped charges and decoupling of free charges in TiO2 from trapped charges. The delocalization and decoupling parameters were evaluated from the equivalent circuit constants, and a numerical model incorporating the determined values reproduced the experimentally observed temperature quenching of photoluminescence.

Ishii, Masashi; Towlson, Brian; Harako, Susumu; Zhao, Xin-wei; Komuro, Shuji; Hamilton, Bruce

2013-02-01

436

Trapping cold atoms with ultrafast laser pulses  

NASA Astrophysics Data System (ADS)

The aim of this research is to pave the way for making a trap for cold neutral atoms based on the force generated by pulses of a mode-locked laser. As an onset towards such a trap we decided to use a far-off-resonance trap (FORT) loaded with cold rubidium atoms from a magneto-optical trap (MOT). Our FORT setup consists of a titanium-sapphire laser that can operate both in continuous wave mode and in mode-locked mode. Our MOT setup uses a magnetic field gradient, and two diode lasers whose frequency is locked very accurately to the atomic transition using polarisation spectroscopy. Since the measurements we do require very precise timing of the order of less than one millisecond between the various phases of the experiment, a time-sequencing program was developed. Using this sophisticated setup, several characteristics of FORTs made with continuous and pulsed lasers were analysed. For example, we have investigated the loading behaviour of the traps and found that under general circumstances there is no significant difference. However, under special conditions it is possible to load more atoms into a pulsed trap. The lifetime of the number of atoms in the trap shows no dependence on the power of the trap laser in the continuous case. For the pulsed trap, however, the increased scattering due to the high peak intensities of the pulses does limit the achievable lifetimes. Moreover, due to the presence of a large number of photoassociation lines, i.e. lines were loosely bound molecules are formed by the interaction of two atoms an a photon, the two-particle losses depend heavily on the wavelength of the trap laser. Furthermore we have done measurements of the temperature of the trapped atoms, which revealed that the temperature is a constant fraction of the trap depth. We also looked at the effects of parametric excitation of the atoms in the FORT. The anharmonicity of the trap formed by the titanium-sapphire laser results in interesting physics, including a change in the average temperature of the atoms, depending on the modulation frequency. We also investigated the trapping behaviour of the FORT at low pulse repetition rates by switching the laser intensity on and off on a kHz scale. We investigated the dependence of the number of atoms on the polarisation of the FORT laser light, both for continuous and pulsed traps. Atoms can be trapped at elliptical polarisations as well, although the number of trapped atoms is less. As the laser is detuned further to the red of the rubidium D line, this effect becomes less and less pronounced, as predicted by our model.

Karssen, L. C.

2008-10-01

437

Equivalence principle implications of modified gravity models  

SciTech Connect

Theories that attempt to explain the observed cosmic acceleration by modifying general relativity all introduce a new scalar degree of freedom that is active on large scales, but is screened on small scales to match experiments. We demonstrate that if such screening occurs via the chameleon mechanism, such as in f(R) theory, it is possible to have order unity violation of the equivalence principle, despite the absence of explicit violation in the microscopic action. Namely, extended objects such as galaxies or constituents thereof do not all fall at the same rate. The chameleon mechanism can screen the scalar charge for large objects but not for small ones (large/small is defined by the depth of the gravitational potential and is controlled by the scalar coupling). This leads to order one fluctuations in the ratio of the inertial mass to gravitational mass. We provide derivations in both Einstein and Jordan frames. In Jordan frame, it is no longer true that all objects move on geodesics; only unscreened ones, such as test particles, do. In contrast, if the scalar screening occurs via strong coupling, such as in the Dvali-Gabadadze-Porrati braneworld model, equivalence principle violation occurs at a much reduced level. We propose several observational tests of the chameleon mechanism: 1. small galaxies should accelerate faster than large galaxies, even in environments where dynamical friction is negligible; 2. voids defined by small galaxies would appear larger compared to standard expectations; 3. stars and diffuse gas in small galaxies should have different velocities, even if they are on the same orbits; 4. lensing and dynamical mass estimates should agree for large galaxies but disagree for small ones. We discuss possible pitfalls in some of these tests. The cleanest is the third one where the mass estimate from HI rotational velocity could exceed that from stars by 30% or more. To avoid blanket screening of all objects, the most promising place to look is in voids.

Hui, Lam; Nicolis, Alberto; Stubbs, Christopher W. [Institute for Strings, Cosmology, and Astroparticle Physics (ISCAP), Department of Physics, Columbia University, New York, New York 10027 (United States); Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

2009-11-15

438

Equivalent source mapping of lunar magnetic field  

NASA Astrophysics Data System (ADS)

JAXA (Japan Aerospace Exploration Agency) shall launch the SELENE (SELenological and ENgineering Explorer) spacecraft this autumn. Amongst many instruments, it has a magnetometer (LMAG: Lunar MAGnetomter) which will measure the magnetic field on the orbit around the Moon. The nominal orbit of the SELENE is about 100km in altitudes for 1 year observation. Although the extended mission is still not determined, LMAG team is requesting a low altitude (less than 50km) observation, if the remaining fuel allows. We are preparing data processing software for the mission. Here, we report an objective scheme for mapping the lunar crustal magnetic field from the orbital measurement data of unequal altitudes. In this study, the magnetic field is restored by solving a linear inverse-problem determining the sources distributed on the lunar surface to satisfy the observational data, which is known as the equivalent source method. Our scheme has three features improving the method: First, the source calculation is performed simultaneously with detrending. Second, magnetic charges (magnetic monopoles) are used as the equivalent sources. It reduces the density of the sources for the same smoothness in produced field, comparing to the dipole sauces. Third, the number of sources is taken large enough to avoid the problem of configuration of the sources, instead the damped least square assuming the strength of each charge is similar to the next one, and the smoothness factor is determined by minimizing Akaike's Bayesian Information Criterion (ABIC). It guarantees the objectivity of the calculation, in other words, there is no adjustable parameter which may depend of the researcher dealing the data analyses. For testing the scheme, we apply this method to the Lunar Prospector magnetometer data, and provide magnetic field map in the region centered at several regions of strong crustal field including the Reiner Gamma anomaly. The stability of the method and the resolution of the anomaly map are found to be satisfactory.

Toyoshima, M.; Shibuya, H.

2007-12-01

439

Task-set inhibition in chunked task sequences  

Microsoft Academic Search

Exploring the hierarchical control relationship between different levels of representation and processing is important for\\u000a understanding how the mind controls itself. In the present study, the relationship between chunking (a sequence-level process)\\u000a and task-set inhibition (a task-level process) in the performance of task sequences was investigated to evaluate the hypothesis\\u000a that within-chunk facilitation reduces then?2 repetition cost (slower performance forn?2

Darryl W. Schneider

2007-01-01

440

Towards the unification of inference structures in medical diagnostic tasks.  

PubMed

The central purpose of artificial intelligence applied to medicine is to develop models for diagnosis and therapy planning at the knowledge level, in the Newell sense, and software environments to facilitate the reduction of these models to the symbol level. The usual methodology (KADS, Common-KADS, GAMES, HELIOS, Protégé, etc) has been to develop libraries of generic tasks and reusable problem-solving methods with explicit ontologies. The principal problem which clinicians have with these methodological developments concerns the diversity and complexity of new terms whose meaning is not sufficiently clear, precise, unambiguous and consensual for them to be accessible in the daily clinical environment. As a contribution to the solution of this problem, we develop in this article the conjecture that one inference structure is enough to describe the set of analysis tasks associated with medical diagnoses. To this end, we first propose a modification of the systematic diagnostic inference scheme to obtain an analysis generic task and then compare it with the monitoring and the heuristic classification task inference schemes using as comparison criteria the compatibility of domain roles (data structures), the similarity in the inferences, and the commonality in the set of assumptions which underlie the functionally equivalent models. The equivalences proposed are illustrated with several examples. Note that though our ongoing work aims to simplify the methodology and to increase the precision of the terms used, the proposal presented here should be viewed more in the nature of a conjecture. PMID:9550854

Mira, J; Rives, J; Delgado, A E; Martínez, R

1998-01-01

441

The new ClusterTrap setup  

NASA Astrophysics Data System (ADS)

ClusterTrap has been designed to investigate properties of atomic clusters in the gas phase with particular emphasis on the dependence on the cluster size and charge state. The combination of cluster source, Penning trap and time-of-flight mass spectrometry allows a variety of experimental schemes including collision-induced dissociation, photo-dissociation, further ionization by electron impact, and electron attachment. Due to the storage capability of the trap extended-delay reaction experiments can be performed. Several recent modifications have resulted in an improved setup. In particular, an electrostatic quadrupole deflector allows the coupling of several sources or detectors to the Penning trap. Furthermore, a linear radio-frequency quadrupole trap has been added for accumulation and ion bunching and by switching the potential of a drift tube the kinetic energy of the cluster ions can be adjusted on their way towards or from the Penning trap. Recently, experiments on multiply negatively charged clusters have been resumed.

Martinez, F.; Marx, G.; Schweikhard, L.; Vass, A.; Ziegler, F.

2011-07-01

442

Hydrogen-Trapping Mechanisms in Nanostructured Steels  

NASA Astrophysics Data System (ADS)

Nanoprecipitation-hardened martensitic bearing steels (100Cr6) and carbide-free nanobainitic steels (superbainite) are examined. The nature of the hydrogen traps present in both is determined via the melt extraction and thermal desorption analysis techniques. It is demonstrated that 100Cr6 can admit large amounts of hydrogen, which is loosely bound to dislocations around room temperature; however, with the precipitation of fine coherent vanadium carbide traps, hydrogen can be immobilized. In the case of carbide-free nanostructured bainite, retained austenite/bainite interfaces act as hydrogen traps, while concomitantly retained austenite limits hydrogen absorption. In nanostructured steels where active hydrogen traps are present, it is shown that the total hydrogen absorbed is proportional to the trapped hydrogen, indicating that melt extraction may be employed to quantify trapping capacity.

Szost, B. A.; Vegter, R. H.; Rivera-Díaz-del-Castillo, Pedro E. J.

2013-10-01

443

All steam traps aren`t equal  

SciTech Connect

Steam traps are automatic valves that sense the difference between steam, air, condensate, and noncondensate gases such as CO{sub 2}. Their objective is to purge air, condensate, and other noncondensate gases and trap steam in the system where it belongs. A properly working trap should never let steam escape. Though the requirements for steam traps are simple, even the most experienced plant engineers and maintenance personnel have trouble in their selection and care. This fact is not surprising when a typical plant using a range of steam pressures can easily have in excess of 100 different steam traps to consider in terms of type, pressure rating, capacity, and manufacturer. There are five major types of steam traps in common use today: inverted bucket, float and thermostatic (F and T), thermodynamic, bimetallic, and thermostatic. Each is described.

Picut, R. [Watson McDaniel Co., Norristown, PA (United States)

1996-09-01

444

Petri net tools for analysis and verification of task scheduling algorithm in real time distributed process control system  

Microsoft Academic Search

This paper first show by formalism that a task scheduling algorithm can be equivalently specified by a set of rules, that is, a set of specification rules can constitute a task scheduling algorithm; and then show that these rules can be translated into a marked Petri net model involving the Petri net place,transitions and arcs that correspond to the states

Chen Qinghua; Wu Yongsen; Zhu Hong

1993-01-01

445

Guidelines for the communication of Biomonitoring Equivalents: Report from the Biomonitoring Equivalents Expert Workshop  

Microsoft Academic Search

Biomonitoring Equivalents (BEs) are screening tools for interpreting biomonitoring data. However, the development of BEs brings to the public a relatively novel concept in the field of health risk assessment and presents new challenges for environmental risk communication. This paper provides guidance on methods for conveying information to the general public, the health care community, regulators and other interested parties

Judy S. LaKind; Lesa L. Aylward; Conrad Brunk; Stephen DiZio; Michael Dourson; Daniel A. Goldstein; Michael E. Kilpatrick; Daniel Krewski; Michael J. Bartels; Hugh A. Barton; Peter J. Boogaard; John Lipscomb; Kannan Krishnan; Monica Nordberg; Miles Okino; Yu-Mei Tan; Claude Viau; Janice W. Yager; Sean M. Hays

2008-01-01

446

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE (PAPER)  

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

447

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE  

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

448

Equivalence topologie des systemes dynamiques nonlineaires autonomes. (Topological equivalence of nonlinear autonomous dynamical systems).  

National Technical Information Service (NTIS)

We show in this paper that the autonomous nonlinear dynamical system (Sigma)(A,B,F): x' = Ax+Bu+F(x) is topologically equivalent to the linear dynamical system (Sigma)(A,B,O): x' = Ax+Bu if the projection of A on the complement in R(sup n) of the controll...

Nguyen Huynh Phan Tran Van Nhung

1995-01-01

449

High quality atomic-layer-deposited ultrathin Si-nitride gate dielectrics with low density of interface and bulk traps  

NASA Astrophysics Data System (ADS)

Interface trap and bulk trap densities of atomic-layer-deposited (ALD) Si-nitride dielectrics have been evaluated by bipolar-voltage-pulse-induced current and electrical-stress-induced leakage-current measurements, respectively. In comparison with the conventional SiO2 dielectrics, significantly lower (~1/3) interface trap density near the conduction band edge is observed in the ALD Si-nitride dielectrics. Moreover, the observed lower interface and bulk trap generations consistently explain the soft-breakdown-free phenomena observed in capacitors with the ALD Si-nitride gate dielectrics. Enhanced dielectric reliability and several other significant features have made the ALD Si-nitride gate dielectrics a front line candidate for extremely thin (equivalent oxide thickness ~1 nm) gate dielectrics of sub-100-nm technology nodes.

Nakajima, Anri; Khosru, Quazi D. M.; Yoshimoto, Takashi; Kasai, Tetsurou; Yokoyama, Shin

2003-07-01

450

Coherency Based Dynamic Equivalents for Transient Stability Studies.  

National Technical Information Service (NTIS)

Phase I of this project provided an analytical basis for developing electromechanical equivalents for outlying, or 'external,' portions of a large power system from network parameters. Phase II was an investigation of equivalent construction on the basis ...

R. W. de Mello R. Podmore K. N. Stanton

1974-01-01

451

The Tree Equivalence Problem for Linear Recursion Schemes  

Microsoft Academic Search

In the paper, a complete system of transformation rules preserving the tree equivalence and a polynomial-time algorithm deciding the tree equivalence of linear polyadic recursion schemes are proposed.

Viktor K. Sabelfeld; A. P. Ershov

1996-01-01

452

46 CFR Appendix A to Part 154 - Equivalent Stress  

Code of Federal Regulations, 2010 CFR

I. Equivalent stress (Ï c) is calculated by the following formula or another formula specially approved by the Commandant (CG-522) as equivalent to the following: EC02FE91.090 where: Ïx =total normal stress in âxâ direction....

2010-10-01

453

Elementary equivalence of Chevalley groups over local rings  

SciTech Connect

It is proved that (elementary) Chevalley groups over local rings with invertible 2 are elementarily equivalent if and only if their types and weight lattices coincide and the initial rings are elementarily equivalent. Bibliography: 25 titles.

Bunina, Elena I [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2010-05-11

454

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2012 CFR

... Table IâGallon Equivalent Measurements for Gaseous Fuels per 100 Standard Cubic Feet Fuel Gallon equivalent measurement Compressed Natural Gas 0.823...823 Liquefied Petroleum Gas (Grade HD-5)* 0.726...

2012-10-01

455

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2011 CFR

... Table IâGallon Equivalent Measurements for Gaseous Fuels per 100 Standard Cubic Feet Fuel Gallon equivalent measurement Compressed Natural Gas 0.823...823 Liquefied Petroleum Gas (Grade HD-5)* 0.726...

2011-10-01

456

Microchip traps and Bose–Einstein condensation  

Microsoft Academic Search

.   The article gives an overview of the rapidly evolving field of magnetic microchip traps (also called ‘atom chips’) for neutral\\u000a atoms. Special attention is given to Bose–Einstein condensation in such traps, to the particular properties of microchip trap\\u000a potentials, and to practical considerations in their design. Scaling laws are developed, which lead to an estimate of the\\u000a ultimate confinement

J. Reichel

2002-01-01

457

In-trap conversion electron spectroscopy  

Microsoft Academic Search

The Penning trap REXTRAP at ISOLDE was used to test the feasibility of in-trap conversion electron spectroscopy. The results of simulations, experiments with solid conversion electron sources as well as first on-line tests with trapped radioactive ions are presented. In addition to obtaining high-resolution spectroscopic data, the detection of conversion electrons was found to be a useful tool for the

L. Weissman; F. Ames; J. Äysto; O. Forstner; K. Reisinger; S. Rinta-Antila

2002-01-01

458

State-insensitive bichromatic optical trapping  

SciTech Connect

We study a scheme for state-insensitive trapping of neutral atoms by using light with two independent wavelengths. In particular, we describe the use of trapping and control lasers to minimize the variance of the potential experienced by a trapped Rb atom in ground and excited states. We present calculated values of wavelength pairs for which the 5s and 5p{sub 3/2} levels have the same ac Stark shifts in the presence of two laser fields.

Arora, Bindiya; Safronova, M. S.; Clark, Charles W. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Joint Quantum Institute, National Institute of Standards and Technology and the University of Maryland, Gaithersburg, Maryland 20899-8410 (United States)

2010-08-15

459

Measurement of light scattering from trapped particles  

Microsoft Academic Search

We have developed an optical tweezers setup combined with a laser light scattering measurement system to measure the elastic light scattering from trapped particles. The setup consists of a near infrared laser (lambda=1064nm), a water immersion objective for trapping, a single or double structure sample cuvette, and a HeNe-laser for illuminating the trapped particles. The light is detected with an

Mikael Collins; Antti Kauppila; Artashes Karmenyan; Lech Gajewski; Krzysztof Szewczyk; Matti Kinnunen; Risto Myllylä

2010-01-01

460

Trapped electrons in solid hydrogen  

SciTech Connect

We report here a relatively large increase in emission of the integrated 800 nm line when pumping the UV absorption and a much smaller increase (by a factor of {approximately}15) upon pumping the IR absorption band in solid D-T at 4.6 K. These data show the 800 run emission is most likely the result of an electron bubble transition. We also present ESR data for electrons in D{sub 2} and H{sub 2} doped with 2% T{sub 2} and pure T{sub 2}. We find there are two components to this absorption, a narrow line component which we attribute to trapped electrons and a broad line component which we attribute to delocalized electrons. The narrow ESR linewidth in the H{sub 2} and D{sub 2} samples are commensurate with the idea of electrons localized in vacancy seeded traps. In solid T{sub 2 } the broad line dominates, implying that most electrons are delocalized due to the large concentration of electrons and other impurities. We find that the temperature and time dependence of the electron concentration from the 800 nm line is similar to the unpaired atoms as measured previously with ESR.

Collins, G.W.; Magnotta, F.; Mapoles, E.R.; Lorenzana, H.E.

1993-06-01

461

Microwave Spectroscopy of Trapped Antihydrogen  

NASA Astrophysics Data System (ADS)

Theory predicts that, under CPTfootnotetextCharge conjugation, Parity inversion, and Time reversal. symmetry, the laws of physics make no distinction between matter and anti-matter. We have every reason to believe that equal amounts of both were produced in the early universe, following the Big Bang. However, our observable universe is overwhelmingly made up of matter. ALPHA is an international project located at CERN and involves ˜30 physicists from 15 different institutions. The primary goal of the collaboration is to investigate this gaping discrepancy between theoretical expectations and reality by precise comparison of matter and anti-matter, in particular hydrogen and antihydrogen. A critical milestone was reported in November 2010, the first-ever stable and reproducible magnetic confinement of neutral antihydrogen atoms. Shortly after, in June 2011, ALPHA announced the long-time (1000 s) trapping of antihydrogen, opening the door to precision spectroscopy. In March 2012, the first proof-of-principle spectroscopic measurement performed on trapped antihydrogen atoms using microwave radiationfootnotetextC. Amole, et al., (ALPHA collaboration), Nature 483, 439 (2012).. Detailed aspects of this measurement is presented in this talk.

Dehghani Ashkezari, Mohammad

2012-10-01

462

Experiments with trapped ^210Fr  

NASA Astrophysics Data System (ADS)

Francium, the heaviest of alkali atoms, is an excellent system for the study of weak interactions in atoms because of its large atomic number. It has been difficult to study its atomic structure in great detail since there are no stable isotopes and sufficient quantities have not been available. At the Stony Brook Superconducting LINAC we produce 1 × 10^6 ^210Fr/s in the reaction ^197Au(^18O,5n)^210Fr. The atoms are transported as ions to the vicinity of the trap where they are neutralized and enter the capturing region of a Magneto-Optical Trap (MOT). From the initial [1] capture of ^210Fr into a MOT we have increased the number of atoms to the point where their fluorescence is visible in a CCD camera. The large number of atoms permits the initiation of experiments to study the atomic structure of francium relevant for a parity non-conservation measurement, such as the location of the 8S and 9S electronic states. Work supported by a Precision Measurement Grant from NIST and by NSF. [1] P. A. Voytas, A. Ghosh, G. Gwinner, L. A. Orozco, J. E. Simsarian, G. D. Sprouse, Postdeadline paper APS NPD, Indiana, October 1995; J. E. Simsarian, A. Ghosh, G. Gwinner, L. A. Orozco, G. D. Sprouse and P. A. Voytas (Preprint Dec. 12, 1995).

Sprouse, G. D.; Orozco, L. A.; Shi, W.; Simsarian, J. E.; Zhao, W. Z.

1996-05-01

463

Non-destructive ion trap mass spectrometer and method  

DOEpatents

The invention relates to an ion trap mass spectrometer of the type having an ion trapping volume defined by spaced end caps and a ring electrode. The ion trap includes a small sensing electrode which senses characteristic motion of ions trapped in said trapping volume and provides an image current. Ions are excited into characteristic motion by application of an excitation pulse to the trapped ions. The invention also relates to a method of operating such an ion trap.

Frankevich, Vladimir E. (West Lafayette, IN); Soni, Manish H. (West Lafayette, IN); Nappi, Mario (West Lafayette, IN); Santini, Robert E. (West Lafayette, IN); Amy, Jonathan W. (West Lafayette, IN); Cooks, Robert G. (West Lafayette, IN)

1997-01-01

464

Novel dipole-force atom traps  

SciTech Connect

We discuss our recent experimental demonstrations of three novel atom traps which are all based on the optical dipole force in far-detuned laser light. In the gravito-optical surface trap (GOST), Cs atoms are trapped and cooled by means of an evanescent-wave mirror very closely above a dielectric surface. This trap allows for optical cooling at very high densities and provides good starting conditions for evaporative cooling to quantum degeneracy and the realization of a 2D quantum gas. The conical atom trap (CAT) uses a hollow blue-detuned laser beam in combination with gravity to trap atoms in a dark spatial region. This trap is experimentally simple and provides high loading efficiency, tight confinement, efficient sub-Doppler cooling, and strong suppression of collisional losses. The standing-wave red-detuned (STAR) trap allows one to confine atoms in a shallow optical potential at a very low photon scattering rate, and is thus an interesting tool for studies of the atomic ground-state dynamics in external electro-magnetic fields. We have studied atomic spin polarization in this trap.

Manek, I.; Moslener, U.; Ovchinnikov, Yu. B.; Grimm, R. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Rosenbusch, P. [Sussex Centre for Optical and Atomic Physics, Brighton (United Kingdom); Sidorov, A. I. [School of Physics, University of Melbourne (Australia); Wasik, G. [Institute of Physics, Jagiellonian University, Krakow (Poland); Zielonkowski, M. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Physikalisches Institut der Universitaet, Heidelberg (Germany)

1999-06-11

465

Trapped electron damping of geodesic acoustic mode  

SciTech Connect

Global gyrokinetic particle simulation finds that the collisionless damping rate of the geodesic acoustic mode (GAM) in tokamak is greatly enhanced by trapped electrons in the high-q region of tokamak (q is the safety factor). The electron damping has been identified to arise from the resonance of the GAM oscillation with the trapped electron bounce motion. The contribution of passing electrons to the GAM collisionless damping is much smaller than the trapped electrons. The residual level of the zonal flow is not sensitive to the trapped electron resonance.

Zhang, H. S. [Fusion Simulation Center and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lin, Z. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)

2010-07-15

466

Drug trapping and delivery for Alzheimer's diagnosis.  

PubMed

In this investigation, a new design based on a PANDA ring resonator as an optical trapping tool for tangle protein, molecular motor storage, and delivery is proposed. The optical vortices are generated and the trapping mechanism is controlled in the same way as the conventional optical tweezers. The trapping force is produced by a combination of the gradient field and scattering photons. The required molecular volume is trapped and moved dynamically within the molecular network. The tangle protein and molecular motor can be transported and delivered to the required destinations for Alzheimer's diagnosis by molecular buffer and bus network. PMID:22384850

Jalil, M A; Kamoldilok, Surachart; Saktioto, T; Ong, C T; Yupapin, Preecha P

2012-03-02

467

s-wave pseudopotential for anisotropic traps  

SciTech Connect

Starting from two identical, interacting particles in an isotropic harmonic trap, we employ first-order perturbation theory to derive the effective s-wave pseudopotential operator for a weakly anisotropic trap. It is shown that such a confinement gives rise to a correction of the s-wave scattering length which is proportional to the square of the ratio of the bare scattering length and the oscillator length. The trap pseudopotential depends on the quantum number of the trapped state, and the effect of a weak anisotropy is dominated by its nearest neighbors. Some implications for experiments with cold bosons in tightly confining potentials are discussed briefly.

Pade, Jochen; Block, Martin; Holthaus, Martin [Institut fuer Physik, Carl von Ossietzky Universitaet, D-26111 Oldenburg (Germany)

2003-12-01

468

Hydrodynamic Trap for Single Cells and Particles  

NASA Astrophysics Data System (ADS)

The ability to trap individual particles, cells and macromolecules has revolutionized many fields of science during the last two decades. Several methods of particle trapping and micromanipulation have been developed based on optical, magnetic and electric fields. In this work, we describe an alternative trapping method, the hydrodynamic trap, based on the sole action of hydrodynamic forces in a microfluidic device. A microfluidic cross slot device is fabricated consisting of two perpendicular microchannels where opposing laminar flow streams converge. In this device, a purely extensional flow field is created at the microchannel junction, thereby resulting in a semi-stable potential well at the stagnation point which enables particle trapping. We implement an automated feedback-control mechanism to adjust the location of the stagnation point which facilitates active particle trapping. Using the hydrodynamic trap, we successfully demonstrate trapping and manipulation of single particles and cells for arbitrarily long observation times. This technique offers a new venue for observation of biological materials without surface immobilization, eliminates potentially perturbative optical, magnetic and electric fields, and provides the capability to change the surrounding medium conditions of the trapped object.

Tanyeri, Melikhan; Schroeder, Charles

2010-03-01

469

Chemistry of Perfluoroisobutylene (PFIB) with Nitrone and Nitroso Spin Traps. An EPR/Spin Trapping Study.  

National Technical Information Service (NTIS)

Applying EPR/Spin Trapping techniques, several reactive intermediate species were identified in the reaction of perfluoroisobutylene (PFIB) with nitrone and nitroso spin trap agents: the carbon dioxide radical anion (CO2(-)), a carbonyl fluoride intermedi...

C. M. Arroyo

1996-01-01

470

Relational Frame Theory and Stimulus Equivalence: Conceptual and Procedural Issues  

Microsoft Academic Search

The article begins with a brief outline of the phenomenon of stimulus equivalence and its relationship to human verbal behavior. Relational Frame Theory is then outlined as a behavior-analytic account of both stimulus equivalence and human language. The expe- rimental procedures that have typically been used to examine stimulus equivalence are then considered, before focusing on a series of studies

Dermot Barnes-Holmes; Yvonne Barnes-Holmes; Paul M. Smeets; Veronica Cullinan; Geraldine Leader

2004-01-01

471

Further Results on Partial Order Equivalences on Infinite Systems  

Microsoft Academic Search

In [26], we investigated decidability issues for standard language equivalence for process description languages with two generalisations based on traditional approaches for capturing non-interleaving behaviour: pomset equivalence reflecting global causal dependency, and location equivalence reflecting spatial distribution of events. In this paper, we continue...

Kim Sunesen

1998-01-01

472

The Assessment of Effective Dose Equivalent Using Personnel Dosimeters  

Microsoft Academic Search

From January 1994, U.S. nuclear plants must develop a technically rigorous approach for determining the effective dose equivalent for their work forces. This dissertation explains concepts associated with effective dose equivalent and describes how to assess effective dose equivalent by using conventional personnel dosimetry measurements. A Monte Carlo computer code, MCNP, was used to calculate photon transport through a model

Xie Xu

1994-01-01

473

Equivalent inclusion method for steady state heat conduction in composites  

Microsoft Academic Search

The equivalent inclusion method is proposed to solve the steady state heat conduction problems in composites. This method is analogous to Eshelby's equivalent inclusion method in elasticity. Thus, the solution procedure by this method is very simple, involving only algebraic operations. The equivalent inclusion method developed here is also applicable to the case of high concentrations of ellipsoidal inhomogeneities. As

H Hiroshi; M. Taya

1986-01-01

474

A steganography strategy based on equivalence partitions of hiding units  

Microsoft Academic Search

This paper designs a novel hiding strategy based on an equivalence relation, which can remarkably enhance the quality of stego image without sacrificing the security and capacity of original steganography schemes. According to a constructed equivalence relation based on the capacity of hiding units, all hiding units can be partitioned into equivalence classes. Following that, the hiding procedure is performed

Shaohui Liu; Hongxun Yao; Shengping Zhang; Wen Gao

2010-01-01

475

Diagnosing Measurement Equivalence in Cross-National Research  

Microsoft Academic Search

Many researchers have pointed out that it is necessary to ensure measurement equivalence in cross-national comparative research. Three aspects of measurement equivalence, translation, metric, and calibration equivalence, are necessary to establish the cross-national reliability and validity of items used to measure theoretical constructs. This paper discusses these issues and proposes two recently developed empirical techniques, Multiple Group LISREL and Optimal

Michael R. Mullen

1995-01-01

476

Economic and Politico-Economic Equivalence of Fiscal Policies  

Microsoft Academic Search

We extend “economic equivalence” results, like the Ricardian equivalence proposition, to the political sphere where policy is chosen sequentially. We derive conditions under which a policy regime (summarizing admissible policy choices in every period) and a state are “politico-economically equivalent” to another such pair, in the sense that both pairs give rise to the same equilibrium allocation. We apply the

Mart ´ õn Gonzalez-Eiras; Martin Gonzalez-Eiras

2012-01-01

477

Effects of a Meaningful, a Discriminative, and a Meaningless Stimulus on Equivalence Class Formation  

PubMed Central

Thirty college students attempted to form three 3-node 5-member equivalence classes under the simultaneous protocol. After concurrent training of AB, BC, CD, and DE relations, all probes used to assess the emergence of symmetrical, transitive, and equivalence relations were presented for two test blocks. When the A–E stimuli were all abstract shapes, none of 10 participants formed classes. When the A, B, D, and E stimuli were abstract shapes and the C stimuli were meaningful pictures, 8 of 10 participants formed classes. This high yield may reflect the expansion of existing classes that consist of the associates of the meaningful stimuli, rather than the formation of the ABCDE classes, per se. When the A–E stimuli were abstract shapes and the C stimuli became SDs prior to class formation, 5 out of 10 participants formed classes. Thus, the discriminative functions served by the meaningful stimuli can account for some of the enhancement of class formation produced by the inclusion of a meaningful stimulus as a class member. A sorting task, which provided a secondary measure of class formation, indicated the formation of all three classes when the emergent relations probes indicated the same outcome. In contrast, the sorting test indicated “partial” class formation when the emergent relations test indicated no class formation. Finally, the effects of nodal distance on the relatedness of stimuli in the equivalence classes were not influenced by the functions served by the C stimuli in the equivalence classes.

Fields, Lanny; Arntzen, Erik; Nartey, Richard K; Eilifsen, Christoffer

2012-01-01

478

Antibacterial Drug Development Task Force  

Center for Drug Evaluation (CDER)

... The CDER Antibacterial Drug Development Task Force has been created to support the development of new antibacterial drugs. ... More results from www.fda.gov/drugs/developmentapprovalprocess/developmentresources

479

Learning an L1-regularized Gaussian Bayesian network in the equivalence class space.  

PubMed

Learning the structure of a graphical model from data is a common task in a wide range of practical applications. In this paper, we focus on Gaussian Bayesian networks, i.e., on continuous data and directed acyclic graphs with a joint probability density of all variables given by a Gaussian. We propose to work in an equivalence class search space, specifically using the k-greedy equivalence search algorithm. This, combined with regularization techniques to guide the structure search, can learn sparse networks close to the one that generated the data. We provide results on some synthetic networks and on modeling the gene network of the two biological pathways regulating the biosynthesis of isoprenoids for the Arabidopsis thaliana plant. PMID:20083459

Vidaurre, Diego; Bielza, Concha; Larrañaga, Pedro

2010-01-15

480

Traps and seals I. Structural/fault-seal and hydrodynamic traps  

SciTech Connect

This text is a reprint of earlier papers which are part of the Treatis of Petroleum Geology. This text is part of a two volume set on oil and gas traps. The papers in these two volumes deal mainly with the mechanics of trapping hydrocarbons and with trap types. Methods of exploring for traps are discussed in another volume entitled Methods of Exploration. Numerous case studies and fluid mechanics papers are provided in this text along with the classification techniques.

Foster, N.H.; Beaumont, E.A. (comps.)

1988-01-01

481

Time to task failure and muscle activation vary with load type for a submaximal fatiguing contraction with the lower leg  

Microsoft Academic Search

ABSTRACT The purpose was to compare the time to failure and muscle activation patterns for a sustained isometric submaximal,contraction with the dorsiflexor muscles when the foot was restrained to a force transducer (force task) compared,with supporting an equivalent inertial load and unrestrained (position task). Fifteen men and women,(mean ± SD; 21.1 ± 1.4 years) performed the force and position tasks

Sandra K. Hunter; Tejin Yoon; Joseph Farinella; Erin E. Griffith; Alexander V. Ng

2008-01-01

482

TaskArchitect: taking the work out of task analysis  

Microsoft Academic Search

This paper takes a pragmatic approach to the design of a task analysis support tool. Instead of proposing a new approach to analysis, it looks at the common requirements for providing support to a wide range of task analysis practitioners, each applying their own style of analysis. The paper describes the range of activities undertaken when practicing what is commonly

Jon Stuart; Richard Penn

2004-01-01

483

Go with the flow: How to master a nonlinear multiple-cue judgment task.  

PubMed

The authors examined the cognitive processes that participants use in linear and nonlinear multiple-cue judgment tasks, hypothesizing that people are unable to use explicit cue abstraction in a nonlinear task, instead turning to exemplar memory. Experiment 1 confirmed that people are unable to use cue abstraction in nonlinear tasks but failed to confirm the hypothesized, spontaneous shift to exemplar memory. Instead, the participants appeared to be trapped in persistent and futile attempts to abstract the cue-criterion relations. Only after being instructed to rely on exemplar memory in Experiment 2 did they master the nonlinear task. The results suggest that adaptive shifts of representation need not occur spontaneously and that analytical thought may sometimes harm performance in nonlinear tasks. PMID:17087590

Olsson, Anna-Carin; Enkvist, Tommy; Juslin, Peter

2006-11-01

484

How varying pest and trap densities affect Tribolium castaneum (Coleoptera: Tenebrionidae) capture in pheromone traps  

Technology Transfer Automated Retrieval System (TEKTRAN)

The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is an important insect pest in food processing facilities. Pheromone trapping is frequently used to monitor red flour beetle populations in structures; however, the optimal trap density and the relationship between trap ...

485

Adaptive optics in an optical trapping system for enhanced lateral trap stiffness at depth  

NASA Astrophysics Data System (ADS)

In optical trapping systems the trap stiffness, or spring constant, deteriorates dramatically with trap depth due to optical aberrations and system misalignment. This can severely hamper studies that employ optical tweezers to make accurate quantitative measurements. Here, a deformable membrane mirror is used, in conjunction with a random search algorithm, to correct for these aberrations by optimizing on a merit factor that is directly proportional to the trap stiffness. Previous studies have sought to address this issue but none have used a merit factor that is directly proportional to the trap stiffness. We demonstrate that the lateral trap stiffness, measured with and without aberration correction at increasing depths, improves throughout the trapping range of a conventional trap and allows us to extend the maximum depth at which we can trap from 136 to 166 ?m. At a depth of 131 ?m, trap stiffness improved by factors of 4.37 and 3.31 for the x- and y-axes respectively. The aberration correction resulted in deformable membrane mirror shapes where a single shape could be applied throughout a wide range of trap depths, showing significant improvement, and had the added benefit of making the lateral trapping forces more uniform in x and y.

Müllenbroich, M. C.; McAlinden, N.; Wright, A. J.

2013-07-01

486

Simultaneous trapping of two different atomic species in a vapor-cell magneto-optical trap  

Microsoft Academic Search

We have produced a magneto-optical trap that simultaneously confines two different atomic species: sodium and potassium. A measurement of the sodium trap loss rate constant due to collisions with cold potassium atoms was performed. We extract this rate constant by measuring the temporal behavior of the loading process of the sodium trap in the presence and absence of cold potassium.

M. S. Santos; P. Nussenzveig; L. G. Marcassa; K. Helmerson; J. Flemming; S. C. Zilio; V. S. Bagnato

1995-01-01

487

Trapping efficiency of funnel and cup-traps for epigeal arthropods  

Microsoft Academic Search

Catches of six different groups of arthropods, collected in four habitat types, were analysed for the efficiency of two types of pitfall traps: plastic cups and plastic funnels. An ANOVA indicates influences of trap type, habitat and systematic group (spiders stand out) on capture success (Tab. 2). Correlation analysis of numbers captured per cm trap diameter shows significant dependence of

MARTIN K. OBRIST; PETER DUELLI

488

Quantum mechanics in rotating-radio-frequency traps and Penning traps with a quadrupole rotating field  

SciTech Connect

Quantum-mechanical analysis of ion motion in a rotating-radio-frequency (rrf) trap or in a Penning trap with a quadrupole rotating field is carried out. Rrf traps were introduced by Hasegawa and Bollinger [Phys. Rev. A 72, 043404 (2005)]. The classical motion of a single ion in this trap is described by only trigonometric functions, whereas in the conventional linear radio-frequency (rf) traps it is by the Mathieu functions. Because of the simple classical motion in the rrf trap, it is expected that the quantum-mechanical analysis of the rrf traps is also simple compared to that of the linear rf traps. The analysis of Penning traps with a quadrupole rotating field is also possible in a way similar to the rrf traps. As a result, the Hamiltonian in these traps is the same as the two-dimensional harmonic oscillator, and energy levels and wave functions are derived as exact results. In these traps, it is found that one of the vibrational modes in the rotating frame can have negative energy levels, which means that the zero-quantum-number state (''ground'' state) is the highest energy state.

Abe, K.; Hasegawa, T. [Department of Physics, Keio University, Kanagawa 223-8522 (Japan)

2010-03-15

489

Standing-wave trap and single-beam gradient optical trap: experiments and biological applications  

NASA Astrophysics Data System (ADS)

The possibilities of laser micro-manipulation using a single beam trap and standing wave trap are demonstrated on polystyrene micro-spheres of diameters 15, 5, 1 and 0.295 micrometers , on protozoa cells of families Colpidium, Paramecium, and on Mouse Carcinoma cells. The optical trap based on the standing wave is experimentally presented for the first time.

Zemanek, Pavel; Sramek, Libor; Jonas, Alexandr; Moravcik, Z.; Janisch, R.; Liska, Miroslav

1999-07-01

490

Correlates of academic procrastination: discomfort, task aversiveness, and task capability.  

PubMed

The relationships among five aspects of academic procrastination--behavioral delay, personal upset about the delay, task aversiveness, task capability, and the desire to reduce behavioral delay--were investigated in 10th-grade Israeli students (N = 195). Upset about delay was weakly related to delay itself, and--unlike delay--was strongly related to perceived capability to perform academic tasks and to the desire to change delaying behavior. Students delayed more on academic tasks labeled unpleasant than pleasant, were neutral in between, and were correspondingly more upset about the former than the latter. They more frequently acknowledged reasons for academic procrastination that were less threatening to their self-image (e.g., problems in time management) than reasons that were more threatening (e.g., lack of ability). Interest in reducing delay is related more to self-perceived ability to handle tasks than to time spent procrastinating or reasons given for procrastinating. PMID:7760291

Milgram, N; Marshevsky, S; Sadeh, C

1995-03-01

491

Ability and task constraint determinants of complex task performance.  

PubMed

Previous research on basic information-processing tasks has suggested that there may be a dissociation between the underlying process determinants of task performance and associations with ability measures. This study investigates this dissociation in the context of a complex skill-learning task-an air traffic control simulation called TRACON. A battery of spatial, numerical, and perceptual speed ability tests were administered, along with extensive task practice. After practice, manipulations of task requirements and system consistency were introduced. Ability correlations with performance revealed a dissociation between some manipulations that have effects on performance means and the corresponding correlations with reference abilities. Implications for integrating experimental and differential approaches to explaining performance and possible avenues for improved selection measures are discussed. PMID:12240931

Ackerman, Phillip L; Cianciolo, Anna T

2002-09-01

492

Comparative efficiency of six stable fly (Diptera: Muscidae) traps.  

PubMed

Five adhesive traps and the Nzi cloth-target trap were compared to determine their trapping efficiency and biases for stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae). Two configurations of the BiteFree prototype trap, constructed of polyethylene terephthalate, were most efficient for trapping stable flies, whereas the EZ trap was least efficient. The two Alsynite traps, Broce and Olson, were intermediate to the BiteFree prototype and EZ traps. All adhesive traps collected a ratio of approximately two males for each female. Approximately 50% of the flies collected on the adhesive traps, both male and female, were blood fed, and 20% were vitellogenic. The Nzi trap collected an older component of the stable fly population, 81% blood fed and 62% vitellogenic, but it was much less efficient than the adhesive traps. The effectiveness of the BiteFree prototype trap indicates that materials other than Alsynite are attractive to stable flies. PMID:16937700

Taylor, David B; Berkebile, Dennis

2006-08-01

493

Equivalence classes generated by sequence training.  

PubMed Central

In Experiment 1, 3, adult females were taught with verbal instructions and contingencies to select, in sequence, three arbitrary visual stimuli from an array of five stimuli. After four different sequences were taught, match-to-sample tests assessed emergent conditional relations among all stimuli that had been selected in the same order in the sequences. Subjects' performances indicated development of four stimulus classes, three based on ordinal position and one based on nonselection. Next, match-to-sample training established conditional relations between each of four novel figures and one member of each of the ordinal stimulus classes. Tests confirmed that the classes were equivalence classes, each expanded by one new member. In subsequent sequence tests, the new stimuli were selected in a sequence that was consistent with ordinal class membership. Experiment 2 replicated Experiment 1 with 2 different adult females, but the verbal instructions were omitted. Results were similar to Experiment 1, except that extensive review and retesting were required before expansion of the ordinal classes with the novel figures was observed.

Sigurdardottir, Z G; Green, G; Saunders, R R

1990-01-01

494

Derivation of Biomonitoring Equivalents for cyfluthrin.  

PubMed

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline, and are derived by integrating available data on pharmacokinetics with existing chemical risk assessments. This study reviews available health-based exposure guidance values for cyfluthrin from Health Canada, the United States Environmental Protection Agency (USEPA), and the World Health Organization/Food and Agriculture Organization. BE values corresponding to the oral reference dose (RfD), or acceptable daily intake (ADI) estimates from these agencies were derived based on data on excretion fractions of the urinary metabolite 4-fluoro-3-phenoxybenzoic acid (FPBA), which is a metabolite specific to cyfluthrin. These values may be used as screening tools for evaluation of biomonitoring data for cyfluthrin as the metabolite FPBA in the context of existing risk assessments and for prioritization of the potential need for additional risk assessment efforts for cyfluthrin relative to other chemicals. PMID:19751788

Hays, Sean M; Aylward, Lesa L; Gagné, Michelle; Krishnan, Kannan

2009-09-12

495

Dynamic equivalence between atomic and colloidal liquids  

NASA Astrophysics Data System (ADS)

We show that the kinetic-theoretical self-diffusion coefficient of an atomic fluid plays the same role as the short-time self-diffusion coefficient DS in a colloidal liquid, in the sense that the dynamic properties of the former, at times much longer than the mean free time, and properly scaled with DS, will be indistinguishable from those of a colloidal liquid with the same interaction potential. One important consequence of such dynamic equivalence is that the ratio DL/DS of the long-time to the short-time self-diffusion coefficients must then be the same for both an atomic and a colloidal system characterized by the same inter-particle interactions. This naturally extends to atomic fluids a well-known dynamic criterion for freezing of colloidal liquids (Löwen H. et al., Phys. Rev. Lett., 70 (1993) 1557). We corroborate these predictions by comparing molecular and Brownian dynamics simulations on the hard-sphere system and on other soft-sphere model systems, representative of the “hard-sphere”dynamic universality class.

López-Flores, Leticia; Mendoza-Méndez, Patricia; Sánchez-Díaz, Lu