Contact mechanics for coated spheres that includes the transition from weak to strong adhesion

DOE PAGES

Reedy, Earl David

2007-09-01

Recently published results for a rigid spherical indenter contacting a thin, linear elastic coating on a rigid planar substrate have been extended to include the case of two contacting spheres, where each sphere is rigid and coated with a thin, linear elastic material. This is done by using an appropriately chosen effective radius and coating modulus. Finally, the earlier work has also been extended to provide analytical results that span the transition between the previously derived Derjaguin–Müller–Toporov (DMT)-like (work of adhesion/coating-modulus ratio is small) and Johnson–Kendall–Roberts (JKR)-like (work of adhesion/coating-modulus ratio is large) limits.

Shock-Bubble Heating of the Intracluster Medium

NASA Astrophysics Data System (ADS)

Friedman, Samuel H.; Heinz, S.; Churazov, E.

2011-01-01

Active galactic nuclei (AGN) Feedback via extragalactic jets requires a thermalization of the energy injected into the intracluster medium (ICM) in order for energy feedback to occur. Heinz and Churazov (2005) proposed a method using shock waves and previously inflated bubbles in the ICM to extract energy from the shock waves and turn the energy into rotational kinetic energy. This energy would decay and allow heating to occur elsewhere throughout the galaxy cluster. In this paper, we extend to three dimensions (3D) the previous work using hydrodynamic simulations. We also compare our results to previous related work done performed experimentally.

Long Work Hours and Family Life: A Cross-National Study of Employees' Concerns

ERIC Educational Resources Information Center

Wharton, Amy S.; Blair-Loy, Mary

2006-01-01

Work-family conflict is a pressing research and policy issue. The authors extend previous scholarship on this issue by studying elite employees worries about the effects of long work hours on those in their personal life. This issue is researched cross-nationally in a sample of managers and professionals based in the United States, London, and…

Player Types, Play Styles, and Play Complexity: Updating the Entertainment Grid

ERIC Educational Resources Information Center

Rademacher Mena, Ricardo Javier

2012-01-01

In a previous work the author created the Education and Entertainment Grid by combining various taxonomies from the fields of play and learning. In this paper, a section of this grid known as the Entertainment Grid will be extended by including previously unused elements of Richard Bartle's online player types and Robert Caillois' play complexity.…

Characteristics of a Cognitive Tool That Helps Students Learn Diagnostic Problem Solving

ERIC Educational Resources Information Center

Danielson, Jared A.; Mills, Eric M.; Vermeer, Pamela J.; Preast, Vanessa A.; Young, Karen M.; Christopher, Mary M.; George, Jeanne W.; Wood, R. Darren; Bender, Holly S.

2007-01-01

Three related studies replicated and extended previous work (J.A. Danielson et al. (2003), "Educational Technology Research and Development," 51(3), 63-81) involving the Diagnostic Pathfinder (dP) (previously Problem List Generator [PLG]), a cognitive tool for learning diagnostic problem solving. In studies 1 and 2, groups of 126 and 113…

Role of hybridization in the superconducting properties of an extended d p Hubbard model: a detailed numerical study

NASA Astrophysics Data System (ADS)

Calegari, E. J.; Magalhães, S. G.; Gomes, A. A.

2005-04-01

The Roth's two-pole approximation has been used by the present authors to study the effects of the hybridization in the superconducting properties of a strongly correlated electron system. The model used is the extended Hubbard model which includes the d-p hybridization, the p-band and a narrow d-band. The present work is an extension of our previous work (J. Mod. Phys. B 18(2) (2004) 241). Nevertheless, some important correlation functions necessary to estimate the Roth's band shift, are included together with the temperature T and the Coulomb interaction U to describe the superconductivity. The superconducting order parameter of a cuprate system, is obtained following Beenen and Edwards formalism. Here, we investigate in detail the change of the order parameter associated to temperature, Coulomb interaction and Roth's band shift effects on superconductivity. The phase diagram with Tc versus the total occupation number nT, shows the difference respect to the previous work.

Forward collision warning requirements project : refining the CAMP crash alert timing approach by examining "last second" braking and lane change maneuvers under various kinematic conditions

DOT National Transportation Integrated Search

2003-01-01

This final report describes a follow-on study to the previous Crash Avoidance Metrics Partnership (CAMP) human factors work addressing Forward Collision Warning (FCW) timing requirements. This research extends this work by gathering not only "last-se...

Archetypal Narratives in Career Counselling: A Chaos Theory Application

ERIC Educational Resources Information Center

Pryor, Robert G. L.; Bright, Jim E. H.

2008-01-01

This paper seeks to extend previous work on narrative career counselling by considering the role of plot within clients' narratives. Seven archetypal narratives derived from the work of Booker (2004) are introduced that represent systems of meaning to provide insight into how individuals interpret their experience. These plots can be understood…

Studies of extra-solar Oort Clouds and the Kuiper disk

NASA Technical Reports Server (NTRS)

Stern, S. Alan

1992-01-01

In 1991 we detected extended 1.1 mm emission around Fomalhaut (alpha PsA) at distances in order of magnitude beyond previous detections. This emission is plausibly related to the presence of an extended comet cloud, like our Oort Cloud, and may therefore represent indirect evidence for the formation of a planetary system at Fomalhaut. We propose now to extend this work to create a map of the angular and spatial extent of this emission. Fomalhaut is the only known main-sequence, submm-resolved IR excess source besides beta Pic.

Extended access to methamphetamine self-administration up-regulates dopamine transporter levels 72 hours after withdrawal in rats.

PubMed

D'Arcy, Christina; Luevano, Joe E; Miranda-Arango, Manuel; Pipkin, Joseph A; Jackson, Jonathan A; Castañeda, Eddie; Gosselink, Kristin L; O'Dell, Laura E

2016-01-01

Previous studies have demonstrated that there are persistent changes in dopamine systems following withdrawal from methamphetamine (METH). This study examined changes in striatal dopamine transporter (DAT), tyrosine hydroxylase (TH) and dopamine receptor 2 (D2) 72 h after withdrawal from METH intravenous self- administration (IVSA). Rats were given limited (1h) or extended (6h) access to METH IVSA (0.05 mg/kg/0.1 ml infusion) for 22 days. Controls did not receive METH IVSA. The rats given extended access to IVSA displayed higher METH intake during the first hour of drug access compared to rats given limited access. Extended access to METH also produced a concomitant increase in striatal DAT levels relative to drug-naïve controls. There were no changes in TH or D2 levels across groups. Previous studies have reported a decrease in striatal DAT levels during protracted periods (>7 days) of withdrawal from METH IVSA. This study extends previous work by showing an increase in striatal DAT protein expression during an earlier time point of withdrawal from this drug. These results are an important step toward understanding the dynamic changes in dopamine systems that occur during different time points of withdrawal from METH IVSA. Copyright © 2015 Elsevier B.V. All rights reserved.

Self calibrating monocular camera measurement of traffic parameters.

DOT National Transportation Integrated Search

2009-12-01

This proposed project will extend the work of previous projects that have developed algorithms and software : to measure traffic speed under adverse conditions using un-calibrated cameras. The present implementation : uses the WSDOT CCTV cameras moun...

Vortex lattices in binary mixtures of repulsive superfluids

NASA Astrophysics Data System (ADS)

Mingarelli, Luca; Keaveny, Eric E.; Barnett, Ryan

2018-04-01

We present an extension of the framework introduced in previous work [L. Mingarelli, E. E. Keaveny, and R. Barnett, J. Phys.: Condens. Matter 28, 285201 (2016), 10.1088/0953-8984/28/28/285201] to treat multicomponent systems, showing that new degrees of freedom are necessary in order to obtain the desired boundary conditions. We then apply this extended framework to the coupled Gross-Pitaevskii equations to investigate the ground states of two-component systems with equal masses, thereby extending previous work in the lowest Landau limit [E. J. Mueller and T.-L. Ho, Phys. Rev. Lett. 88, 180403 (2002), 10.1103/PhysRevLett.88.180403] to arbitrary interactions within Gross-Pitaevskii theory. We show that away from the lowest Landau level limit, the predominant vortex lattice consists of two interlaced triangular lattices. Finally, we derive a linear relation which accurately describes the phase boundaries in the strong interacting regimes.

Broken Replica Symmetry Bounds in the Mean Field Spin Glass Model

NASA Astrophysics Data System (ADS)

Guerra, Francesco

By using a simple interpolation argument, in previous work we have proven the existence of the thermodynamic limit, for mean field disordered models, including the Sherrington-Kirkpatrick model, and the Derrida p-spin model. Here we extend this argument in order to compare the limiting free energy with the expression given by the Parisi Ansatz, and including full spontaneous replica symmetry breaking. Our main result is that the quenched average of the free energy is bounded from below by the value given in the Parisi Ansatz, uniformly in the size of the system. Moreover, the difference between the two expressions is given in the form of a sum rule, extending our previous work on the comparison between the true free energy and its replica symmetric Sherrington-Kirkpatrick approximation. We give also a variational bound for the infinite volume limit of the ground state energy per site.

From Higher Education to Work Patterns of Labor Market Entry in Germany and the US

ERIC Educational Resources Information Center

Jacob, Marita; Weiss, Felix

2010-01-01

Comparative studies describing the transition from higher education to work have often simplified the complex transition processes involved. In this paper we extend previous research by taking into account several steps that comprise labor market entry, e.g., recurrent education leading to more than one instance of labor market entry. By comparing…

State Actions To Restructure Schools: First Steps. Results in Education Series.

ERIC Educational Resources Information Center

David, Jane L.; And Others

The widening mismatch between the skills of the work force and the skill demands of the work place underlie the need for school restructuring. Fourth in a series, this document builds on and extends the issues discussed in the National Governors' Association's (NGA) previous publications and reports on case studies of early restructuring efforts…

Connecting the Forgotten Half: The School-to-Work Transition of Noncollege-Bound Youth

ERIC Educational Resources Information Center

Ling, Thomson J.; O'Brien, Karen M.

2013-01-01

While previous research has examined the school-to-work transition of noncollege-bound youth, most have considered how a limited set of variables relate to job attainment at a single point in time. This exploratory study extended beyond the identification of constructs associated with obtaining a job to investigate how several factors, collected…

Explaining Perceptions of Administrative Support among Prison Treatment Staff: A Spotlight on Deputy Wardens in Charge of Treatment

ERIC Educational Resources Information Center

Garland, Brett E.; McCarty, William P.

2006-01-01

This paper explores how perceptions of administrative support among 83 treatment staff working in a midwest prison system vary according to personal and work-related variables. It extends on previous literature by: (1) analyzing how perceptions of administrative support vary exclusively among prison treatment staff; (2) focusing on a single type…

Effect of magnetization boundary condition on cavity magnon polariton of YIG thin film.

PubMed

Jiang, H H; Xiao, Y; Hu, C M; Guo, H; Xia, K

2018-06-22

Motivated by recent studies of cavity magnon polariton (CMP), we extended a previous theoretical work to generalize microwave transmission calculation with various magnetization boundary condition of YIG thin film embedded in cavity. It is found that numerical implementation given in this paper can be easily applied to other magnetization boundary condition and extended to magnetic multilayers. Numerical results show that ferromagnetic resonance mode of microwave transmission spectrum, which is absent in previous calculation, can be recovered by altering the pinning condition of surface spins. The demonstrated reliability of our theory opens attractive perspectives for studying CMP of thin film with complicated surface magnetization distribution and magnetic multilayers.

Effect of magnetization boundary condition on cavity magnon polariton of YIG thin film

NASA Astrophysics Data System (ADS)

Jiang, H. H.; Xiao, Y.; Hu, C. M.; Guo, H.; Xia, K.

2018-06-01

Motivated by recent studies of cavity magnon polariton (CMP), we extended a previous theoretical work to generalize microwave transmission calculation with various magnetization boundary condition of YIG thin film embedded in cavity. It is found that numerical implementation given in this paper can be easily applied to other magnetization boundary condition and extended to magnetic multilayers. Numerical results show that ferromagnetic resonance mode of microwave transmission spectrum, which is absent in previous calculation, can be recovered by altering the pinning condition of surface spins. The demonstrated reliability of our theory opens attractive perspectives for studying CMP of thin film with complicated surface magnetization distribution and magnetic multilayers.

Hospital employee job resourcefulness: an empirical study and implications for health care marketing.

PubMed

Harris, Eric G; Artis, Andrew B; Fogliasso, Chris; Fleming, David E

2007-01-01

In today's competitive hospital marketing environment, it is imperative that administrators ensure that their hospitals are operating as efficiently and as effectively as possible. "Doing more with less" has become a mandate for hospital administrators and employees. The current research replicates and extends previous work devoted to this topic by examining the job resourcefulness construct in a hospital setting. Job resourcefulness, an individual difference variable, assesses the degree to which employees are able to overcome resource constraints in the pursuit of job-related goals. The work builds upon previous work and contributes to the hospital marketing literature by examining the relationships between resourcefulness, personality influencers, role stressors, and job tenure. Research implications and suggestions for future work in the area are presented.

Towards a Standardized Line List for G 191-B2B and other DA Type Objects

NASA Astrophysics Data System (ADS)

Preval, S. P.; Barstow, M. A.; Holberg, J. B.; Dickinson, N. J.

2013-01-01

We present a comprehensive analysis of the far UV spectrum of G 191-B2B over the range of 900-1700Å using co-added data from the FUSE and STIS archives. While previous identifications made by Holberg et al. (2003) are reaffirmed in this work, it is found that many previously unidentified lines can now be attributed to Fe, Ni, and a few lighter metals. Future work includes extending this detailed analysis to a wider range of DA objects, in the expectation that a more complete analysis of their atmospheres can be realised.

To Gain, Retain and Retrain: The Role of Post-School Education for People with a Disability. Research Report

ERIC Educational Resources Information Center

Polidano, Cain; Vu, Ha

2011-01-01

This study extends previous work of Cain Polidano and Kostas Mavromaras (2010) which showed that vocational education and training (VET) qualifications had a positive effect on the chances of finding work for people with a disability. It teases out this earlier result by looking at whether, for those who already have a disability, completing a VET…

Constraints on Gusev Basin Infill from the Mars Orbiter Laser Altimeter (MOLA) Topography

NASA Technical Reports Server (NTRS)

Carter, B. L.; Frey, H.; Sakimoto, S. E. H.; Roark, J.

2001-01-01

MOLA topography provides volume estimates for Gusev crater based on higher resolution. Revisiting work previously done by Grin and Cabrol (1997), we find a substantial increase in original sedimentation estimates. Additional information is contained in the original extended abstract.

A VARIABLE REACTIVITY MODEL FOR ION BINDING TO ENVIRONMENTAL SORBENTS

EPA Science Inventory

The conceptual and mathematical basis for a new general-composite modeling approach for ion binding to environmental sorbents is presented. The work extends the Simple Metal Sorption (SiMS) model previously presented for metal and proton binding to humic substances. A surface com...

Hypnosis and Encounter Group Volunteers: A Validation Study of the Sensation-Seeking Scale

ERIC Educational Resources Information Center

Stanton, H. E.

1976-01-01

Individual differences in optimal level of stimulation as operationalized by the Sensation Seeking Scale significantly differentiated volunteers for hypnosis and encounter groups from non-volunteers. This confirmed predictions and extended the findings of previous work regarding encounter group volunteers. (NG)

Generalizing Landauer's principle

NASA Astrophysics Data System (ADS)

Maroney, O. J. E.

2009-03-01

In a recent paper [Stud. Hist. Philos. Mod. Phys. 36, 355 (2005)] it is argued that to properly understand the thermodynamics of Landauer’s principle it is necessary to extend the concept of logical operations to include indeterministic operations. Here we examine the thermodynamics of such operations in more detail, extending the work of Landauer to include indeterministic operations and to include logical states with variable entropies, temperatures, and mean energies. We derive the most general statement of Landauer’s principle and prove its universality, extending considerably the validity of previous proofs. This confirms conjectures made that all logical operations may, in principle, be performed in a thermodynamically reversible fashion, although logically irreversible operations would require special, practically rather difficult, conditions to do so. We demonstrate a physical process that can perform any computation without work requirements or heat exchange with the environment. Many widespread statements of Landauer’s principle are shown to be special cases of our generalized principle.

An Examination of the Relationship between Motor Coordination and Executive Functions in Adolescents

ERIC Educational Resources Information Center

Rigoli, Daniela; Piek, Jan P.; Kane, Robert; Oosterlaan, Jaap

2012-01-01

Aim: Research suggests important links between motor coordination and executive functions. The current study examined whether motor coordination predicts working memory, inhibition, and switching performance, extending previous research by accounting for attention-deficit-hyperactivity disorder (ADHD) symptomatology and other confounding factors,…

The Â-genus as a Projective Volume form on the Derived Loop Space

NASA Astrophysics Data System (ADS)

Grady, Ryan

2018-06-01

In the present work, we extend our previous work with Gwilliam by realizing \\hat {A}(X) as the projective volume form associated to the BV operator in our quantization of a one-dimensional sigma model. We also discuss the associated integration/expectation map. We work in the formalism of L ∞ spaces, objects of which are computationally convenient presentations for derived stacks. Both smooth and complex geometry embed into L ∞ spaces and we specialize our results in both of these cases.

Hierarchical Bayesian Models of Subtask Learning

ERIC Educational Resources Information Center

Anglim, Jeromy; Wynton, Sarah K. A.

2015-01-01

The current study used Bayesian hierarchical methods to challenge and extend previous work on subtask learning consistency. A general model of individual-level subtask learning was proposed focusing on power and exponential functions with constraints to test for inconsistency. To study subtask learning, we developed a novel computer-based booking…

Matrilineal Family Ties and Marital Dissolution in Ghana

ERIC Educational Resources Information Center

Takyi, Baffour K.; Gyimah, Stephen Obeng

2007-01-01

Although previous work has attributed the instability of African marriages to the diffusion of Western norms and values in the region, fewer attempts have been made to empirically assess how Africa's internal institutional structures, such as extended kinship ties, impact marital outcomes. Guided by rational choice and exchange theories, we argue…

Energy Transfer and a Recurring Mathematical Function

ERIC Educational Resources Information Center

Atkin, Keith

2013-01-01

This paper extends the interesting work of a previous contributor concerning the analogies between physical phenomena such as mechanical collisions and the transfer of power in an electric circuit. Emphasis is placed on a mathematical function linking these different areas of physics. This unifying principle is seen as an exciting opportunity to…

Information Distortion in the Evaluation of a Single Option

ERIC Educational Resources Information Center

Bond, Samuel D.; Carlson, Kurt A.; Meloy, Margaret G.; Russo, J. Edward; Tanner, Robin J.

2007-01-01

Extending previous work on biased predecisional processing, we investigate the distortion of information during the evaluation of a single option. A coherence-based account of the evaluation task suggests that individuals will form an initial assessment of favorability toward the option and then bias their evaluation of subsequent information to…

Scale of Academic Emotion in Science Education: Development and Validation

ERIC Educational Resources Information Center

Chiang, Wen-Wei; Liu, Chia-Ju

2014-01-01

Contemporary research into science education has generally been conducted from the perspective of "conceptual change" in learning. This study sought to extend previous work by recognizing that human rationality can be influenced by the emotions generated by the learning environment and specific actions related to learning. Methods used…

Problem Solving Under Time-Constraints.

ERIC Educational Resources Information Center

Richardson, Michael; Hunt, Earl

A model of how automated and controlled processing can be mixed in computer simulations of problem solving is proposed. It is based on previous work by Hunt and Lansman (1983), who developed a model of problem solving that could reproduce the data obtained with several attention and performance paradigms, extending production-system notation to…

Cultural propagation on social networks

NASA Astrophysics Data System (ADS)

Kuperman, M. N.

2006-04-01

In this work we present a model for the propagation of culture on networks of different topology and by considering different underlying dynamics. We extend a previous model proposed by Axelrod by letting a majority govern the dynamics of changes. This in turn allows us to define a Lyapunov functional for the system.

Functional Analytic Psychotherapy with Juveniles Who Have Committed Sexual Offenses

ERIC Educational Resources Information Center

Newring, Kirk A. B.; Wheeler, Jennifer G.

2012-01-01

We have previously discussed the application of Functional Analytic Psychotherapy (FAP) with adults who have committed sexual offense behaviors (Newring & Wheeler, 2010). The present entry borrows heavily from the foundation presented in that chapter, and extends this approach to working with adolescents, youth, and juveniles with sexual offense…

Generalized Detectability for Discrete Event Systems

PubMed Central

Shu, Shaolong; Lin, Feng

2011-01-01

In our previous work, we investigated detectability of discrete event systems, which is defined as the ability to determine the current and subsequent states of a system based on observation. For different applications, we defined four types of detectabilities: (weak) detectability, strong detectability, (weak) periodic detectability, and strong periodic detectability. In this paper, we extend our results in three aspects. (1) We extend detectability from deterministic systems to nondeterministic systems. Such a generalization is necessary because there are many systems that need to be modeled as nondeterministic discrete event systems. (2) We develop polynomial algorithms to check strong detectability. The previous algorithms are based on observer whose construction is of exponential complexity, while the new algorithms are based on a new automaton called detector. (3) We extend detectability to D-detectability. While detectability requires determining the exact state of a system, D-detectability relaxes this requirement by asking only to distinguish certain pairs of states. With these extensions, the theory on detectability of discrete event systems becomes more applicable in solving many practical problems. PMID:21691432

Unified theory of effective interaction

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

Takayanagi, Kazuo, E-mail: k-takaya@sophia.ac.jp

2016-09-15

We present a unified description of effective interaction theories in both algebraic and graphic representations. In our previous work, we have presented the Rayleigh–Schrödinger and Bloch perturbation theories in a unified fashion by introducing the main frame expansion of the effective interaction. In this work, we start also from the main frame expansion, and present various nonperturbative theories in a coherent manner, which include generalizations of the Brandow, Brillouin–Wigner, and Bloch–Horowitz theories on the formal side, and the extended Krenciglowa–Kuo and the extended Lee–Suzuki methods on the practical side. We thus establish a coherent and comprehensive description of both perturbativemore » and nonperturbative theories on the basis of the main frame expansion.« less

Dorsal and ventral working memory-related brain areas support distinct processes in contextual cueing.

PubMed

Manginelli, Angela A; Baumgartner, Florian; Pollmann, Stefan

2013-02-15

Behavioral evidence suggests that the use of implicitly learned spatial contexts for improved visual search may depend on visual working memory resources. Working memory may be involved in contextual cueing in different ways: (1) for keeping implicitly learned working memory contents available during search or (2) for the capture of attention by contexts retrieved from memory. We mapped brain areas that were modulated by working memory capacity. Within these areas, activation was modulated by contextual cueing along the descending segment of the intraparietal sulcus, an area that has previously been related to maintenance of explicit memories. Increased activation for learned displays, but not modulated by the size of contextual cueing, was observed in the temporo-parietal junction area, previously associated with the capture of attention by explicitly retrieved memory items, and in the ventral visual cortex. This pattern of activation extends previous research on dorsal versus ventral stream functions in memory guidance of attention to the realm of attentional guidance by implicit memory. Copyright © 2012 Elsevier Inc. All rights reserved.

The Perceived Value of Maths and Academic Self-Efficacy in the Appraisal of Fear Appeals Used Prior to a High-Stakes Test as Threatening or Challenging

ERIC Educational Resources Information Center

Putwain, David William; Symes, Wendy

2014-01-01

Previous work has examined how messages communicated to students prior to high-stakes exams, that emphasise the importance of avoiding failure for subsequent life trajectory, may be appraised as threatening. In two studies, we extended this work to examine how students may also appraise such messages as challenging or disregard them as being of…

Workplace characteristics and work-to-family conflict: does caregiving frequency matter?

PubMed

Brown, Melissa; Pitt-Catsouphes, Marcie

2013-01-01

Many workers can expect to provide care to an elder relative at some point during their tenure in the workforce. This study extends previous research by exploring whether caregiving frequency (providing care on a regular, weekly basis vs. intermittently) moderates the relationship between certain workplace characteristics and work-to-family conflict. Utilizing a sample of 465 respondents from the National Study of the Changing Workforce (Families and Work Institute, 2008), results indicate that access to workplace flexibility has a stronger effect on reducing work-to-family conflict among intermittent caregivers than among those who provide care regularly.

Passion and Burnout in College Students

ERIC Educational Resources Information Center

Saville, Bryan K.; Bureau, Alex; Eckenrode, Claire; Maley, Michelle

2018-01-01

Previous research on passion and burnout has shown that teachers, including college faculty, who show high levels of harmonious passion toward their work experience lower burnout than teachers who have high levels of obsessive passion. In the present study, we extended this line of research to college students. We found that students who were…

A Framework for Evaluating and Enhancing Alignment in Self-Regulated Learning Research

ERIC Educational Resources Information Center

Dent, Amy L.; Hoyle, Rick H.

2015-01-01

We discuss the articles of this special issue with reference to an important yet previously only implicit dimension of study quality: alignment across the theoretical and methodological decisions that collectively define an approach to self-regulated learning. Integrating and extending work by leaders in the field, we propose a framework for…

Social and biophysical variation in regional timber harvest regimes

Treesearch

Jonathan R. Thompson; Charles D. Canham; Luca Morreale; David B. Kittredge; Brett Butler

2017-01-01

In terms of adult tree mortality, harvesting is the most prevalent disturbance in northeastern United States forests. Previous studies have demonstrated that stand structure and tree species composition are important predictors of harvest. We extend this work to investigate how social factors further influence harvest regimes. By coupling the Forest Inventory and...

Applied Linguistics Redux: A Derridean Exploration of Alzheimer Lifehistories

ERIC Educational Resources Information Center

Ramanathan, Vaidehi

2008-01-01

Advocating a position of self-critique, whereby we revisit our old research sites to dis-assemble our prior thinking in relation to our current cognitions, this paper offers, among other things, a critical revisitation and Derridean interpretation of one of my previous long-term, ethnographic endeavours: my extended work with the memories and…

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

Calva-tildeo, M.O.; Reboucas, M.J.; Teixeira, A.F.F.

The breakdown of causality in homogeneous Goedel-type space-time manifolds is examined. An extension of Reboucas--Tiomno (RT) and Accioly--Goncalves studies is made. The existence of noncausal curves is also investigated under two different conditions on the energy-momentum tensor. An integral representation of the infinitesimal generators of isometries is obtained, extending previous works on the RT geometry.

Examining Explanatory Biases in Young Children's Biological Reasoning

ERIC Educational Resources Information Center

Legare, Cristine H.; Gelman, Susan A.

2014-01-01

Despite the well-established literature on explanation in early childhood, little is known about what constrains children's explanations. State change and negative outcomes were examined as potential explanatory biases in the domain of naïve biology, extending upon previous work in the domain of naïve physics. In two studies, preschool children…

Coordination of Oral and Laryngeal Movements in the Perceptually Fluent Speech of Adults Who Stutter

ERIC Educational Resources Information Center

Max, Ludo; Gracco, Vincent L.

2005-01-01

This work investigated whether stuttering and nonstuttering adults differ in the coordination of oral and laryngeal movements during the production of perceptually fluent speech. This question was addressed by completing correlation analyses that extended previous acoustic studies by others as well as inferential analyses based on the…

Migration, Remittances and Educational Stratification among Blacks in Apartheid and Post-Apartheid South Africa

ERIC Educational Resources Information Center

Lu, Yao; Treiman, Donald J.

2011-01-01

This article extends previous work on family structure and children's education by conceptualizing migration as a distinct form of family disruption that reduces parental input but brings substantial economic benefits through remittances. It examines the multiple and countervailing effects of migration on schooling in the context of substantial…

Relational Demography in Coaching Dyads

ERIC Educational Resources Information Center

Sagas, Michael; Paetzold, Ramona; Ashley, Frank

2005-01-01

The decline in the proportion of female head coaches in the intercollegiate ranks is one of the most significant issues in the realm of women's sports today. To extend the body of research that has studied this topic, we investigated the impact relational demographic effects on the work attitudes of coaches, which differs from previous research…

General Anisotropy Identification of Paperboard with Virtual Fields Method

Treesearch

J.M. Considine; F. Pierron; K.T. Turner; D.W. Vahey

2014-01-01

This work extends previous efforts in plate bending of Virtual Fields Method (VFM) parameter identification to include a general 2-D anisotropicmaterial. Such an extension was needed for instances in which material principal directions are unknown or when specimen orientation is not aligned with material principal directions. A new fixture with a multiaxial force...

Epistemic Match: A Pedagogical Concept for Understanding How Students Fit into the Chosen Subject

ERIC Educational Resources Information Center

O'Siochru, Cathal; Norton, Lin

2014-01-01

Previous studies have suggested that a student's personal epistemological beliefs can be a predictor of their academic performance. The current research aimed to extend this work by exploring whether the disciplinary epistemological beliefs presented to students in their classes and assessments might mediate the relationship between students'…

Refinement of horizontal resolution in dynamical downscaling of climate information using WRF: Costs, benefits, and lessons learned

EPA Science Inventory

Dynamical downscaling techniques have previously been developed by the U.S. Environmental Protection Agency (EPA) using a nested WRF at 108- and 36-km. Subsequent work extended one-way nesting down to 12-km resolution. Recently, the EPA Office of Research and Development used com...

Synthesizing Information from Language Samples and Standardized Tests in School-Age Bilingual Assessment

ERIC Educational Resources Information Center

Ebert, Kerry Danahy; Pham, Giang

2017-01-01

Purpose: Although language samples and standardized tests are regularly used in assessment, few studies provide clinical guidance on how to synthesize information from these testing tools. This study extends previous work on the relations between tests and language samples to a new population--school-age bilingual speakers with primary language…

Expertise-Based Differences in Search and Option-Generation Strategies

ERIC Educational Resources Information Center

Raab, Markus; Johnson, Joseph G.

2007-01-01

The current work builds on option-generation research using experts of various skill levels in a realistic task. We extend previous findings that relate an athlete's performance strategy to generated options and subsequent choices in handball. In a 2-year longitudinal study, we present eye-tracking data to independently verify decision strategies…

Children's Natural Conversations Following Exposure to a Rumor: Linkages to Later False Reports

ERIC Educational Resources Information Center

Principe, Gabrielle F.; Cherson, Mollie; DiPuppo, Julie; Schindewolf, Erica

2012-01-01

Previous research has shown that children naturally propagate overheard false rumors and that the circulation of such information can induce children and their peers to wrongly recall actually experiencing rumored-but-nonexperienced events. The current study extends this work by recording 3- to 6-year-olds' naturally occurring conversations…

Reasoning Maps: A Generally Applicable Method for Characterizing Hypothesis-Testing Behaviour. Research Report

ERIC Educational Resources Information Center

White, Brian

2004-01-01

This paper presents a generally applicable method for characterizing subjects' hypothesis-testing behaviour based on a synthesis that extends on previous work. Beginning with a transcript of subjects' speech and videotape of their actions, a Reasoning Map is created that depicts the flow of their hypotheses, tests, predictions, results, and…

A Re-Examination of the Community of Inquiry Framework: Social Network and Content Analysis

ERIC Educational Resources Information Center

Shea, Peter; Hayes, Suzanne; Vickers, Jason; Gozza-Cohen, Mary; Uzuner, Sedef; Mehta, Ruchi; Valchova, Anna; Rangan, Prahalad

2010-01-01

This study provides a simultaneous examination of all components of the Community of Inquiry (CoI) framework (Garrison, Anderson & Archer, 2000; Anderson, Rourke, Garrison & Archer, 2001; and Rourke, Garrison, Anderson & Archer, 1999) and seeks to extend previous work into the nature, development, and relationships between the constructs of…

Spatial Dependence and Heterogeneity in Bayesian Factor Analysis: A Cross-National Investigation of Schwartz Values

ERIC Educational Resources Information Center

Stakhovych, Stanislav; Bijmolt, Tammo H. A.; Wedel, Michel

2012-01-01

In this article, we present a Bayesian spatial factor analysis model. We extend previous work on confirmatory factor analysis by including geographically distributed latent variables and accounting for heterogeneity and spatial autocorrelation. The simulation study shows excellent recovery of the model parameters and demonstrates the consequences…

Appraising Lexical Bundles in Mathematics Classroom Discourse: Obligation and Choice

ERIC Educational Resources Information Center

Herbel-Eisenmann, Beth; Wagner, David

2010-01-01

Working from a large corpus of transcripts from secondary mathematics classrooms, we identify patterns of speech that encode interpersonal positioning. We extend our analysis from a previous article (Herbel-Eisenmann, Wagner & Cortes, Educ Stud Math, 2010, in press), in which we introduced a concept from corpus linguistics--a "lexical bundle,"…

On the covariant gauge {alpha} of the linearized gravity in de Sitter spacetime

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

Cheong, Lee Yen

2012-09-26

In previous work, we studied the linearized gravity with covariant gauge {beta}= 2/3 and {alpha}= 5/3. It was found that the sum of the source and initial contributions reproduces the correct field configuration over the whole de Sitter spacetime. In this paper, we extend this work to generalizing the linearized gravitational field in an arbitrary value of the gauge parameter {alpha} but the gauge parameter {beta} remains the same.

Prediction of heterotrimeric protein complexes by two-phase learning using neighboring kernels

PubMed Central

2014-01-01

Background Protein complexes play important roles in biological systems such as gene regulatory networks and metabolic pathways. Most methods for predicting protein complexes try to find protein complexes with size more than three. It, however, is known that protein complexes with smaller sizes occupy a large part of whole complexes for several species. In our previous work, we developed a method with several feature space mappings and the domain composition kernel for prediction of heterodimeric protein complexes, which outperforms existing methods. Results We propose methods for prediction of heterotrimeric protein complexes by extending techniques in the previous work on the basis of the idea that most heterotrimeric protein complexes are not likely to share the same protein with each other. We make use of the discriminant function in support vector machines (SVMs), and design novel feature space mappings for the second phase. As the second classifier, we examine SVMs and relevance vector machines (RVMs). We perform 10-fold cross-validation computational experiments. The results suggest that our proposed two-phase methods and SVM with the extended features outperform the existing method NWE, which was reported to outperform other existing methods such as MCL, MCODE, DPClus, CMC, COACH, RRW, and PPSampler for prediction of heterotrimeric protein complexes. Conclusions We propose two-phase prediction methods with the extended features, the domain composition kernel, SVMs and RVMs. The two-phase method with the extended features and the domain composition kernel using SVM as the second classifier is particularly useful for prediction of heterotrimeric protein complexes. PMID:24564744

Percolation of binary disk systems: Modeling and theory

DOE PAGES

Meeks, Kelsey; Tencer, John; Pantoya, Michelle L.

2017-01-12

The dispersion and connectivity of particles with a high degree of polydispersity is relevant to problems involving composite material properties and reaction decomposition prediction and has been the subject of much study in the literature. This paper utilizes Monte Carlo models to predict percolation thresholds for a two-dimensional systems containing disks of two different radii. Monte Carlo simulations and spanning probability are used to extend prior models into regions of higher polydispersity than those previously considered. A correlation to predict the percolation threshold for binary disk systems is proposed based on the extended dataset presented in this work and comparedmore » to previously published correlations. Finally, a set of boundary conditions necessary for a good fit is presented, and a condition for maximizing percolation threshold for binary disk systems is suggested.« less

Time-Extended Policies in Mult-Agent Reinforcement Learning

NASA Technical Reports Server (NTRS)

Tumer, Kagan; Agogino, Adrian K.

2004-01-01

Reinforcement learning methods perform well in many domains where a single agent needs to take a sequence of actions to perform a task. These methods use sequences of single-time-step rewards to create a policy that tries to maximize a time-extended utility, which is a (possibly discounted) sum of these rewards. In this paper we build on our previous work showing how these methods can be extended to a multi-agent environment where each agent creates its own policy that works towards maximizing a time-extended global utility over all agents actions. We show improved methods for creating time-extended utilities for the agents that are both "aligned" with the global utility and "learnable." We then show how to crate single-time-step rewards while avoiding the pi fall of having rewards aligned with the global reward leading to utilities not aligned with the global utility. Finally, we apply these reward functions to the multi-agent Gridworld problem. We explicitly quantify a utility's learnability and alignment, and show that reinforcement learning agents using the prescribed reward functions successfully tradeoff learnability and alignment. As a result they outperform both global (e.g., team games ) and local (e.g., "perfectly learnable" ) reinforcement learning solutions by as much as an order of magnitude.

Extended capture range for focus-diverse phase retrieval in segmented aperture systems using geometrical optics.

PubMed

Jurling, Alden S; Fienup, James R

2014-03-01

Extending previous work by Thurman on wavefront sensing for segmented-aperture systems, we developed an algorithm for estimating segment tips and tilts from multiple point spread functions in different defocused planes. We also developed methods for overcoming two common modes for stagnation in nonlinear optimization-based phase retrieval algorithms for segmented systems. We showed that when used together, these methods largely solve the capture range problem in focus-diverse phase retrieval for segmented systems with large tips and tilts. Monte Carlo simulations produced a rate of success better than 98% for the combined approach.

The Emotional Knots of Academicity: A Collective Biography of Academic Subjectivities and Spaces

ERIC Educational Resources Information Center

Charteris, Jennifer; Gannon, Susanne; Mayes, Eve; Nye, Adele; Stephenson, Lauren

2016-01-01

The highly imagined and contested space of higher education is invested with an affectively loaded "knowledge economy optimism". Drawing on recent work in affect and critical geography, this paper considers the e/affects of the promises of the knowledge economy on its knowledge workers. We extend previous analyses of the discursive…

High-resolution low-frequency fluctuation map of a multimode laser diode subject to filtered optical feedback via a fiber Bragg grating.

PubMed

Baladi, Fadwa; Lee, Min Won; Burie, Jean-René; Bettiati, Mauro A; Boudrioua, Azzedine; Fischer, Alexis P A

2016-07-01

A highly detailed and extended map of low-frequency fluctuations is established for a high-power multi-mode 980 nm laser diode subject to filtered optical feedback from a fiber Bragg grating. The low-frequency fluctuations limits and substructures exhibit substantial differences with previous works.

Predictive Cache Modeling and Analysis

DTIC Science & Technology

2011-11-01

metaheuristic /bin-packing algorithm to optimize task placement based on task communication characterization. Our previous work on task allocation showed...Cache Miss Minimization Technology To efficiently explore combinations and discover nearly-optimal task-assignment algorithms , we extended to our...it was possible to use our algorithmic techniques to decrease network bandwidth consumption by ~25%. In this effort, we adapted these existing

Institutional Productivity Ratings Based on Publications in Nine Literacy Journals: 1992-2005

ERIC Educational Resources Information Center

Morrison, Timothy G.; Wilcox, Brad

2008-01-01

This study extended the work of three previous studies that compared the scholarly productivity of faculty members in universities as represented in nine literacy journals. The top 25 universities were identified and this study shows that several institutions have remained consistent through the years as those that produce the largest amount of…

Zoning of an agricultural field using a fuzzy indicator model in combination with tool for multi-attributed decision-making

USDA-ARS?s Scientific Manuscript database

Zoning of agricultural fields is an important task for utilization of precision farming technology. This paper extends previously published work entitled “Zoning of an agricultural field using a fuzzy indicator model” to a general case where there is disagreement between groups of managers or expert...

Bias in Cross-Sectional Analyses of Longitudinal Mediation: Partial and Complete Mediation under an Autoregressive Model

ERIC Educational Resources Information Center

Maxwell, Scott E.; Cole, David A.; Mitchell, Melissa A.

2011-01-01

Maxwell and Cole (2007) showed that cross-sectional approaches to mediation typically generate substantially biased estimates of longitudinal parameters in the special case of complete mediation. However, their results did not apply to the more typical case of partial mediation. We extend their previous work by showing that substantial bias can…

Evaluating the consistency of understorey vegetation response to forest thinning through synthetic analysis of operational-scale experiments

Treesearch

Duncan S. Wilson; Paul D. Anderson; Klaus J. Puettmann

2009-01-01

We attempted to extend the inference scope of several detailed songbird habitat restoration studies in western Oregon to the broader region through a reanalysis and synthesis of five largescale management experiments. This previous work demonstrated the importance of understorey vegetation to songbird habitat. However, individual studies have shown conflicting results...

Maternal Pre-Pregnancy Obesity and Risk for Inattention and Negative Emotionality in Children

ERIC Educational Resources Information Center

Rodriguez, Alina

2010-01-01

Objective: This study aimed to replicate and extend previous work showing an association between maternal pre-pregnancy adiposity and risk for attention deficit hyperactivity disorder (ADHD) symptoms in children. Methods: A Swedish population-based prospective pregnancy-offspring cohort was followed up when children were 5 years old (N = 1,714).…

Relations among Grade 4 Students' Perceptions of Autonomy, Engagement in Science, and Reading Motivation

ERIC Educational Resources Information Center

Taboada Barber, Ana; Buehl, Michelle M.

2013-01-01

The authors extend previous work on students' perceptions of teachers' autonomy-enhancing and autonomy-suppressing behaviors in relation to students' engagement to a more situated context (i.e., two Grade 4 science instructional conditions instead of school in general) and a linguistically diverse population (i.e., Hispanic students). They also…

Use of a Differential Observing Response to Expand Restricted Stimulus Control

ERIC Educational Resources Information Center

Walpole, Carrie Wallace; Roscoe, Eileen M.; Dube, William V.

2007-01-01

This study extends previous work on the use of differential observing responses (DOR) to remediate atypically restricted stimulus control. A participant with autism had high matching-to-sample accuracy scores with printed words that had no letters in common (e.g., "cat," "lid," "bug") but poor accuracy with words that had two letters in common…

Examining the Effects of Residence and Gender on College Student Adjustment in Iran: Implications for Psychotherapists

ERIC Educational Resources Information Center

Mohammadi, Mehdi; Schwitzer, Alan M.; Nunnery, John

2010-01-01

This study examined the effects of on-campus residence, in comparison with commuter status, on academic performance, vocational commitment, self-efficacy, and perceptions of the college environment among female and male Iranian students at Shiraz University, Iran. The study sought to extend previous work investigating the effects of college…

Narrative Skill in Children with Early Unilateral Brain Injury: A Possible Limit to Functional Plasticity

ERIC Educational Resources Information Center

Demir, Ozlem Ece; Levine, Susan C.; Goldin-Meadow, Susan

2010-01-01

Children with pre- or perinatal brain injury (PL) exhibit marked plasticity for language learning. Previous work has focused mostly on the emergence of earlier-developing skills, such as vocabulary and syntax. Here we ask whether this plasticity for earlier-developing aspects of language extends to more complex, later-developing language functions…

Integrated Formal Analysis of Timed-Triggered Ethernet

NASA Technical Reports Server (NTRS)

Dutertre, Bruno; Shankar, Nstarajan; Owre, Sam

2012-01-01

We present new results related to the verification of the Timed-Triggered Ethernet (TTE) clock synchronization protocol. This work extends previous verification of TTE based on model checking. We identify a suboptimal design choice in a compression function used in clock synchronization, and propose an improvement. We compare the original design and the improved definition using the SAL model checker.

Electronic correlation in magnetic contributions to structural energies

NASA Astrophysics Data System (ADS)

Haydock, Roger

For interacting electrons the density of transitions [see http://arxiv.org/abs/1405.2288] replaces the density of states in calculations of structural energies. Extending previous work on paramagnetic metals, this approach is applied to correlation effects on the structural stability of magnetic transition metals. Supported by the H. V. Snyder Gift to the University of Oregon.

Assessing Adolescents' Understanding of and Reactions to Stress in Different Cultures: Results of a Mixed-Methods Approach

ERIC Educational Resources Information Center

Nastasi, Bonnie K.; Hitchcock, John H.; Burkholder, Gary; Varjas, Kristen; Sarkar, Sreeroopa; Jayasena, Asoka

2007-01-01

This article expands on an emerging mixed-method approach for validating culturally-specific constructs (see Hitchcock et al., 2005). Previous work established an approach for dealing with cultural impacts when assessing psychological constructs and the current article extends these efforts into studying stress reactions among adolescents in Sri…

Relationship of Weight-Based Teasing and Adolescents' Psychological Well-Being and Physical Health

ERIC Educational Resources Information Center

Greenleaf, Christy; Petrie, Trent A.; Martin, Scott B.

2014-01-01

Background: To date, research has focused primarily on psychological correlates of weight-based teasing. In this study, we extended previous work by also examining physical health-related variables (eg, physical self-concept and physical fitness [PF]). Methods: Participants included 1419 middle school students (637 boys and 782 girls). Of these,…

Representations of the Extended Poincare Superalgebras in Four Dimensions

NASA Astrophysics Data System (ADS)

Griffis, John D.

Eugene Wigner used the Poincare group to induce representations from the fundamental internal space-time symmetries of (special) relativistic quantum particles. Wigner's students spent considerable amount of time translating passages of this paper into more detailed and accessible papers and books. In 1975, R. Haag et al. investigated the possible extensions of the symmetries of relativistic quantum particles. They showed that the only consistent (super)symmetric extensions to the standard model of physics are obtained by using super charges to generate the odd part of a Lie superalgebra whose even part is generated by the Poincare group; this theory has become known as supersymmetry. In this paper, R. Haag et al. used a notation called supermultiplets to give the dimension of a representation and its multiplicity; this notation is described mathematically in chapter 5 of this thesis. By 1980 S. Ferrara et al. began classifying the representations of these algebras for dimensions greater than four, and in 1986 Strathdee published considerable work listing some representations for the Poincare superalgebra in any finite dimension. This work has been continued to date. We found the work of S. Ferrara et al. to be essential to our understanding extended supersymmetries. However, this paper was written using imprecise language meant for physicists, so it was far from trivial to understand the mathematical interpretation of this work. In this thesis, we provide a "translation" of the previous results (along with some other literature on the Extended Poincare Superalgebras) into a rigorous mathematical setting, which makes the subject more accessible to a larger audience. Having a mathematical model allows us to give explicit results and detailed proofs. Further, this model allows us to see beyond just the physical interpretation and it allows investigation by a purely mathematically adept audience. Our work was motivated by a paper written in 2012 by M. Chaichian et al, which classified all of the unitary, irreducible representations of the extended Poincare superalgebra in three dimensions. We consider only the four dimensional case, which is of interest to physicists working on quantum supergravity models without cosmological constant, and we provide explicit branching rules for the invariant subgroups corresponding to the most physically relevant symmetries of the irreducible representations of the Extended Poincare Superalgebra in four dimensions. However, it is possible to further generalize this work into any finite dimension. Such work would classify all possible finitely extended supersymmetric models.

Microcanonical Szilárd engines beyond the quasistatic regime

NASA Astrophysics Data System (ADS)

Acconcia, Thiago V.; Bonança, Marcus V. S.

2017-12-01

We discuss the possibility of extracting energy from a single thermal bath using microcanonical Szilárd engines operating in finite time. This extends previous works on the topic which are restricted to the quasistatic regime. The feedback protocol is implemented based on linear response predictions of the excess work. It is claimed that the underlying mechanism leading to energy extraction does not violate Liouville's theorem and preserves ergodicity throughout the cycle. We illustrate our results with several examples including an exactly solvable model.

Microcanonical Szilárd engines beyond the quasistatic regime.

PubMed

Acconcia, Thiago V; Bonança, Marcus V S

2017-12-01

We discuss the possibility of extracting energy from a single thermal bath using microcanonical Szilárd engines operating in finite time. This extends previous works on the topic which are restricted to the quasistatic regime. The feedback protocol is implemented based on linear response predictions of the excess work. It is claimed that the underlying mechanism leading to energy extraction does not violate Liouville's theorem and preserves ergodicity throughout the cycle. We illustrate our results with several examples including an exactly solvable model.

Determination of the Secondary Bjerknes Force in Acoustic Resonators on Ground and in Microgravity Conditions

NASA Astrophysics Data System (ADS)

Castro, Luz Angelica; Hoyos, Mauricio

2016-04-01

We propose an experimental methodology to determine the secondary Bjerknes force between rigid particles. Measurements done for different particles sizes showed acoustical inter particles interactions. We use and extend the methodology presented in a previous work. The determination of this force will lead us a better understanding of the aggregation process in acoustic resonators. We report in this work, the results of two parabolic flights campaigns performed at the Airbus A300 ZERO-G (Novespace, France).

Strategies for managing work/life interaction among women and men with variable and unpredictable work hours in retail sales in Québec, Canada.

PubMed

Messing, Karen; Tissot, France; Couture, Vanessa; Bernstein, Stephanie

2014-01-01

Increasingly, work schedules in retail sales are generated by software that takes into account variations in predicted sales. The resulting variable and unpredictable schedules require employees to be available, unpaid, over extended periods. At the request of a union, we studied schedule preferences in a retail chain in Québec using observations, interviews, and questionnaires. Shift start times had varied on average by four hours over the previous week; 83 percent had worked at least one day the previous weekend. Difficulties with work/life balance were associated with schedules and, among women, with family responsibilities. Most workers wanted: more advance notice; early shifts; regular schedules; two days off in sequence; and weekends off. Choices varied, so software could be adapted to take preferences into account. Also, employers could give better advance notice and establish systems for shift exchanges. Governments could limit store hours and schedule variability while prolonging the minimum sequential duration of leave per week.

Squashed Entanglement, k-Extendibility, Quantum Markov Chains, and Recovery Maps

NASA Astrophysics Data System (ADS)

Li, Ke; Winter, Andreas

2018-02-01

Squashed entanglement (Christandl and Winter in J. Math. Phys. 45(3):829-840, 2004) is a monogamous entanglement measure, which implies that highly extendible states have small value of the squashed entanglement. Here, invoking a recent inequality for the quantum conditional mutual information (Fawzi and Renner in Commun. Math. Phys. 340(2):575-611, 2015) greatly extended and simplified in various work since, we show the converse, that a small value of squashed entanglement implies that the state is close to a highly extendible state. As a corollary, we establish an alternative proof of the faithfulness of squashed entanglement (Brandão et al. Commun. Math. Phys. 306:805-830, 2011). We briefly discuss the previous and subsequent history of the Fawzi-Renner bound and related conjectures, and close by advertising a potentially far-reaching generalization to universal and functorial recovery maps for the monotonicity of the relative entropy.

Self-consistent geodesic equation and quantum tunneling from charged AdS black holes

NASA Astrophysics Data System (ADS)

Deng, Gao-Ming

2017-12-01

Some urgent shortcomings in previous derivations of geodesic equations are remedied in this paper. In contrast to the unnatural and awkward treatment in previous works, here we derive the geodesic equations of massive and massless particles in a unified and self- consistent manner. Furthermore, we extend to investigate the Hawking radiation via tunneling from charged black holes in the context of AdS spacetime. Of special interest, the application of the first law of black hole thermodynamics in tunneling integration manifestly simplifies the calculation.

Preparation-induced errors in EPR dosimetry of enamel: pre- and post-crushing sensitivity

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

Haskell, E.H.; Hayes, R.B.; Kenner, G.H.

1996-01-01

Errors in dose estimation as a function of grain size for tooth enamel has been previously shown for beta irradiation after crushing. We tested the effect of gamma radiation applied to specimens before and after crushing. We extend the previous work in that we found that post-crushing irradiation altered the slope of the dose-response curve of the hydroxyapatite signal and produced a grain-size dependent offset. No changes in the slope of the dose-response curve were seen in enamel caps irradiated before crushing.

Longitudinal associations of experiences of adversity and socioeconomic disadvantage during childhood with labour force participation and exit in later adulthood.

PubMed

Fahy, A E; Stansfeld, S A; Smuk, M; Lain, D; van der Horst, M; Vickerstaff, S; Clark, C

2017-06-01

The Extending Working Lives (EWL) agenda seeks to sustain employment up to and beyond traditional retirement ages. This study examined the potential role of childhood factors in shaping labour force participation and exit among older adults, with a view to informing proactive interventions early in the life-course to enhance individuals' future capacity for extending their working lives. Childhood adversity and socioeconomic disadvantage have previously been linked to ill-health across the life-span and sickness benefit in early adulthood. This study builds upon previous research by examining associations between childhood adversity and self-reported labour force participation among older adults (aged 55). Data was from the National Child Development Study - a prospective cohort of all English, Scottish, & Welsh births in one week in 1958. There was evidence for associations between childhood adversity and increased risk of permanent sickness at 55 years - which were largely sustained after adjustment for educational disengagement and adulthood factors (mental/physical health, qualifications, socioeconomic disadvantage). Specifically, children who were abused or neglected were more likely to be permanently sick at 55 years. In addition, among males, those in care, those experiencing illness in the home, and those experiencing two or more childhood adversities were more likely to be permanently sick at 55 years. Childhood factors were also associated with part-time employment and retirement at 55 years. Severe childhood adversities may represent important distal predictors of labour force exit at 55 years, particularly via permanent sickness. Notably, some adversities show associations among males only, which may inform interventions designed to extend working lives. Copyright © 2017 Elsevier Ltd. All rights reserved.

Higher-Order Extended Lagrangian Born–Oppenheimer Molecular Dynamics for Classical Polarizable Models

DOE PAGES

Albaugh, Alex; Head-Gordon, Teresa; Niklasson, Anders M. N.

2018-01-09

Generalized extended Lagrangian Born−Oppenheimer molecular dynamics (XLBOMD) methods provide a framework for fast iteration-free simulations of models that normally require expensive electronic ground state optimizations prior to the force evaluations at every time step. XLBOMD uses dynamically driven auxiliary degrees of freedom that fluctuate about a variationally optimized ground state of an approximate “shadow” potential which approximates the true reference potential. While the requirements for such shadow potentials are well understood, constructing such potentials in practice has previously been ad hoc, and in this work, we present a systematic development of XLBOMD shadow potentials that match the reference potential tomore » any order. We also introduce a framework for combining friction-like dissipation for the auxiliary degrees of freedom with general-order integration, a combination that was not previously possible. These developments are demonstrated with a simple fluctuating charge model and point induced dipole polarization models.« less

Quenching the XXZ spin chain: quench action approach versus generalized Gibbs ensemble

NASA Astrophysics Data System (ADS)

Mestyán, M.; Pozsgay, B.; Takács, G.; Werner, M. A.

2015-04-01

Following our previous work (Pozsgay et al 2014 Phys. Rev. Lett. 113 117203) we present here a detailed comparison of the quench action approach and the predictions of the generalized Gibbs ensemble, with the result that while the quench action formalism correctly captures the steady state, the GGE does not give a correct description of local short-distance correlation functions. We extend our studies to include another initial state, the so-called q-dimer state. We present important details of our construction, including new results concerning exact overlaps for the dimer and q-dimer states, and we also give an exact solution of the quench-action-based overlap-TBA for the q-dimer. Furthermore, we extend our computations to include the xx spin correlations besides the zz correlations treated previously, and give a detailed discussion of the underlying reasons for the failure of the GGE, especially in the light of new developments.

Higher-Order Extended Lagrangian Born-Oppenheimer Molecular Dynamics for Classical Polarizable Models.

PubMed

Albaugh, Alex; Head-Gordon, Teresa; Niklasson, Anders M N

2018-02-13

Generalized extended Lagrangian Born-Oppenheimer molecular dynamics (XLBOMD) methods provide a framework for fast iteration-free simulations of models that normally require expensive electronic ground state optimizations prior to the force evaluations at every time step. XLBOMD uses dynamically driven auxiliary degrees of freedom that fluctuate about a variationally optimized ground state of an approximate "shadow" potential which approximates the true reference potential. While the requirements for such shadow potentials are well understood, constructing such potentials in practice has previously been ad hoc, and in this work, we present a systematic development of XLBOMD shadow potentials that match the reference potential to any order. We also introduce a framework for combining friction-like dissipation for the auxiliary degrees of freedom with general-order integration, a combination that was not previously possible. These developments are demonstrated with a simple fluctuating charge model and point induced dipole polarization models.

Higher-Order Extended Lagrangian Born–Oppenheimer Molecular Dynamics for Classical Polarizable Models

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

Albaugh, Alex; Head-Gordon, Teresa; Niklasson, Anders M. N.

Generalized extended Lagrangian Born−Oppenheimer molecular dynamics (XLBOMD) methods provide a framework for fast iteration-free simulations of models that normally require expensive electronic ground state optimizations prior to the force evaluations at every time step. XLBOMD uses dynamically driven auxiliary degrees of freedom that fluctuate about a variationally optimized ground state of an approximate “shadow” potential which approximates the true reference potential. While the requirements for such shadow potentials are well understood, constructing such potentials in practice has previously been ad hoc, and in this work, we present a systematic development of XLBOMD shadow potentials that match the reference potential tomore » any order. We also introduce a framework for combining friction-like dissipation for the auxiliary degrees of freedom with general-order integration, a combination that was not previously possible. These developments are demonstrated with a simple fluctuating charge model and point induced dipole polarization models.« less

Achieving Affective and Behavioral Outcomes in Culture Learning: The Case for Ethnographic Interviews

ERIC Educational Resources Information Center

Bateman, Blair E.

2004-01-01

This study sought to extend previous research on ethnographic interviews as a method of culture learning in foreign language classes by employing a qualitative case study methodology. Fifty-four university students in a first-year Spanish course worked in pairs to conduct a series of three ethnographic interviews with a native speaker of Spanish.…

Student Perceptions of Peer versus Instructor Facilitation of Asynchronous Online Discussions: Further Findings from Three Cases

ERIC Educational Resources Information Center

Hew, Khe Foon

2015-01-01

This study aims to extend a previous work on the role of peer facilitation of asynchronous online discussions. Specifically, in this paper I report three cases that examine students' preference for peer or instructor facilitation of online discussion forums, as well as their respective reasons for it. These three cases involved the following…

A landscape inventory framework: scenic analyses of the Northern Great Plains

Treesearch

Litton R. Burton Jr.; Robert J. Tetlow

1978-01-01

A set of four visual inventories are proposed. They are designed to document scenic resources for varied scales of application, from regional and general to local and specific. The Northern Great Plains is used as a case study. Scenic analysis and identification of criteria extend earlier work. The inventory is based on (1) study of previously developed landscape...

Using Social Network Graphs as Visualization Tools to Influence Peer Selection Decision-Making Strategies to Access Information about Complex Socioscientific Issues

ERIC Educational Resources Information Center

Yoon, Susan A.

2011-01-01

This study extends previous research that explores how visualization affordances that computational tools provide and social network analyses that account for individual- and group-level dynamic processes can work in conjunction to improve learning outcomes. The study's main hypothesis is that when social network graphs are used in instruction,…

Rethinking Widening Participation in Higher Education: The Role of Social Networks

ERIC Educational Resources Information Center

Fuller, Alison, Ed.; Heath, Sue, Ed.; Johnston, Brenda, Ed.

2011-01-01

Extending the chance for people from diverse backgrounds to participate in Higher Education (HE) is a priority in the UK and many countries internationally. Previous work on widening participation in HE however has focussed on why people choose to go to university but this vital new research has focussed on looking at why people choose not to go.…

Perceived Teacher Credibility and Students' Affect as a Function of Instructors' Use of PowerPoint and Email

ERIC Educational Resources Information Center

Ledbetter, Andrew M.; Finn, Amber N.

2018-01-01

In this study, we extend previous work on instructors' use of technology by examining how students' perceptions of teacher credibility and affective experience differ depending on how frequently instructors use two common forms of instructional technology: PowerPoint, which is typically used "inside" the classroom; and email, which is…

Quantifying Protein Concentrations Using Smartphone Colorimetry: A New Method for an Established Test

ERIC Educational Resources Information Center

Gee, Clifford T.; Kehoe, Eric; Pomerantz, William C. K.; Penn, R. Lee

2017-01-01

Proteins are involved in nearly every biological process, which makes them of interest to a range of scientists. Previous work has shown that hand-held cameras can be used to determine the concentration of colored analytes in solution, and this paper extends the approach to reactions involving a color change in order to quantify protein…

Impact of Posttraumatic Stress Disorder and Injury Severity on Recovery in Children with Traumatic Brain Injury

ERIC Educational Resources Information Center

Kenardy, Justin; Le Brocque, Robyne; Hendrikz, Joan; Iselin, Greg; Anderson, Vicki; McKinlay, Lynne

2012-01-01

The adverse impact on recovery of posttraumatic stress disorder (PTSD) in mild traumatic brain injury (TBI) has been demonstrated in returned veterans. The study assessed this effect in children's health outcomes following TBI and extended previous work by including a full range of TBI severity, and improved assessment of PTSD within a…

Representing the Quantum Object through Fiction in Teaching: The Ontological Contribution of Gamow's Narrative as Part of an Introduction to Quantum Physics

ERIC Educational Resources Information Center

Héraud, Jean-Loup; Lautesse, Philippe; Ferlin, Fabrice; Chabot, Hugues

2017-01-01

Our work extends a previous study of epistemological presuppositions in teaching quantum physics in upper scientific secondary school in France. Here, the problematic reference of quantum theory's concepts is treated at the ontological level (the counterintuitive nature of quantum objects). We consider the approach of using narratives describing…

Sound Radiated by a Wave-Like Structure in a Compressible Jet

NASA Technical Reports Server (NTRS)

Golubev, V. V.; Prieto, A. F.; Mankbadi, R. R.; Dahl, M. D.; Hixon, R.

2003-01-01

This paper extends the analysis of acoustic radiation from the source model representing spatially-growing instability waves in a round jet at high speeds. Compared to previous work, a modified approach to the sound source modeling is examined that employs a set of solutions to linearized Euler equations. The sound radiation is then calculated using an integral surface method.

Teacher Verbal Aggressiveness and Credibility Mediate the Relationship between Teacher Technology Policies and Perceived Student Learning

ERIC Educational Resources Information Center

Finn, Amber N.; Ledbetter, Andrew M.

2014-01-01

In this study, we extend previous work on teacher technology policies by refining the teacher technology policies instrument to account for the technology purpose (social, academic) and type (cell phone, laptop/tablet), and examine a model of teacher technology policies and perceived learning. We found that students are more sensitive to policies…

The Influence of School Factors on Racial Opportunity Cost for High-Achieving Students of Color

ERIC Educational Resources Information Center

Venzant Chambers, Terah T.; Huggins, Kristin Shawn

2014-01-01

Previous work on racial opportunity cost--that is, the price that students of color pay in their pursuit of academic success--is extended here using organizational culture literature to more closely explore the interplay of school culture with the racial opportunity cost experienced by the study participants. Eighteen African American and Latina/o…

An Extended Passive Motion Paradigm for Human-Like Posture and Movement Planning in Redundant Manipulators

PubMed Central

Tommasino, Paolo; Campolo, Domenico

2017-01-01

A major challenge in robotics and computational neuroscience is relative to the posture/movement problem in presence of kinematic redundancy. We recently addressed this issue using a principled approach which, in conjunction with nonlinear inverse optimization, allowed capturing postural strategies such as Donders' law. In this work, after presenting this general model specifying it as an extension of the Passive Motion Paradigm, we show how, once fitted to capture experimental postural strategies, the model is actually able to also predict movements. More specifically, the passive motion paradigm embeds two main intrinsic components: joint damping and joint stiffness. In previous work we showed that joint stiffness is responsible for static postures and, in this sense, its parameters are regressed to fit to experimental postural strategies. Here, we show how joint damping, in particular its anisotropy, directly affects task-space movements. Rather than using damping parameters to fit a posteriori task-space motions, we make the a priori hypothesis that damping is proportional to stiffness. This remarkably allows a postural-fitted model to also capture dynamic performance such as curvature and hysteresis of task-space trajectories during wrist pointing tasks, confirming and extending previous findings in literature. PMID:29249954

Improved detection following Neuro-Eye Therapy in patients with post-geniculate brain damage.

PubMed

Sahraie, Arash; Macleod, Mary-Joan; Trevethan, Ceri T; Robson, Siân E; Olson, John A; Callaghan, Paula; Yip, Brigitte

2010-09-01

Damage to the optic radiation or the occipital cortex results in loss of vision in the contralateral visual field, termed partial cortical blindness or hemianopia. Previously, we have demonstrated that stimulation in the field defect using visual stimuli with optimal properties for blindsight detection can lead to increases in visual sensitivity within the blind field of a group of patients. The present study was aimed to extend the previous work by investigating the effect of positive feedback on recovery of visual sensitivity. Patients' abilities for detection of a range of spatial frequencies within their field defect were determined using a temporal two-alternative forced-choice technique, before and after a period of visual training (n = 4). Patients underwent Neuro-Eye Therapy which involved detection of temporally modulated spatial grating patches at specific retinal locations within their field defect. Three patients showed improved detection ability following visual training. Based on our previous studies, we had hypothesised that should the occipital brain lesion extend anteriorly to the thalamus, little recovery would be expected. Here, we describe one such case who showed no improvements after extensive training. The present study provides further evidence that recovery (a) can be gradual and may require a large number of training sessions (b) can be accelerated using positive feedback and (c) may be less likely to take place if the occipital damage extends anteriorly to the thalamus.

The Priority Inversion Problem and Real-Time Symbolic Model Checking

DTIC Science & Technology

1993-04-23

real time systems unpredictable in subtle ways. This makes it more difficult to implement and debug such systems. Our work discusses this problem and presents one possible solution. The solution is formalized and verified using temporal logic model checking techniques. In order to perform the verification, the BDD-based symbolic model checking algorithm given in previous works was extended to handle real-time properties using the bounded until operator. We believe that this algorithm, which is based on discrete time, is able to handle many real-time properties

Large angle magnetic suspension test fixture

NASA Technical Reports Server (NTRS)

Britcher, Colin P. (Principal Investigator); Huang, Jen-Kuang (Principal Investigator)

1996-01-01

Good progress is being made in several major areas. These include eddy current modelling and analysis, design optimization methods, wind tunnel Magnetic Suspension and Balance Systems (MSBS), payload pointing and vibration isolation systems, and system identification. In addition, another successful International Symposium has been completed, with the Proceedings being printed at the time of writing. These activities continue current work under this Grant and extend previous work on magnetic suspension systems and devices in the Guidance and Control Branch and will permit the demonstration of several new developments in the field of magnetic suspension technology.

School-to-work program participation and the post-high school employment of young adults with disabilities

PubMed Central

Shandra, Carrie L.; Hogan, Dennis P.

2014-01-01

Previous research on the education-to-employment transition for students with disabilities has suggested that participation in school-to-work programs is positively associated with post-high school success. This article utilizes data from the National Longitudinal Survey of Youth 1997 (NLSY97) to extend these findings in several ways. First, we assess the efficacy of specific types of school-based and work-based initiatives, including job shadowing, mentoring, cooperative education, school-sponsored enterprise, technical preparation, internships, and career major. Next, we extend the usual focus on the employment outcomes of work status and financial compensation to consider job-specific information on the receipt of fringe benefits. Overall, results from longitudinal multivariate analyses suggest that transition initiatives are effective in facilitating vocational success for this population; however, different aspects of school-to-work programs are beneficial for different aspects of employment. School-based programs are positively associated with stable employment and full-time work while work-based programs most consistently increase the likelihood that youth with disabilities will be employed in jobs that provide fringe benefits. Analyses also indicate that – once individuals with disabilities are stably employed – they can be employed in “good” jobs that provide employee benefits. PMID:25309111

A swallowtail catastrophe model for the emergence of leadership in coordination-intensive groups.

PubMed

Guastello, Stephen J; Bond, Robert W

2007-04-01

This research extended the previous studies concerning the swallowtail catastrophe model for leadership emergence to coordination-intensive groups. Thirteen 4-person groups composed of undergraduates played in Intersection coordination (card game) task and were allowed to talk while performing it; 13 other groups worked nonverbally. A questionnaire measured leadership emergence at the end of the game along with other social contributions to the groups' efforts. The swallowtail catastrophe model that was evident in previous leadership emergence phenomena in creative problem solving and production groups was found here also. All three control parameters were identified: a general participation variable that was akin to K in the rugged landscape model of self-organization, task control, and whether the groups worked verbally or nonverbally. Several new avenues for future research were delineated.

Testing and extending the group engagement model: linkages between social identity, procedural justice, economic outcomes, and extrarole behavior.

PubMed

Blader, Steven L; Tyler, Tom R

2009-03-01

Two field studies tested and extended the group engagement model (Tyler & Blader, 2000, Tyler & Blader, 2003) by examining the model with regard to employee extrarole behavior. Consistent with the group engagement model's predictions, results of these studies indicate that the social identities employees form around their work groups and their organizations are strongly related to whether employees engage in extrarole behaviors. Moreover, the studies demonstrated that social identity explains the impact of other factors that have previously been linked to extrarole behavior. In particular, the findings indicate that social identity mediates the effect of procedural justice judgments and economic outcomes on supervisor ratings of extrarole behavior. Overall, these studies provide compelling indication that social identity is an important determinant of behavior within work organizations and provide strong support for the application of the group engagement model in organizational settings. (c) 2009 APA, all rights reserved.

The Reverse of Social Anxiety Is Not Always the Opposite: The Reverse-Scored Items of the Social Interaction Anxiety Scale Do Not Belong

ERIC Educational Resources Information Center

Rodebaugh, Thomas L.; Woods, Carol M.; Heimberg, Richard G.

2007-01-01

Although well-used and empirically supported, the Social Interaction Anxiety Scale (SIAS) has a questionable factor structure and includes reverse-scored items with questionable utility. Here, using samples of undergraduates and a sample of clients with social anxiety disorder, we extend previous work that opened the question of whether the…

The Bioelectromagnetics Society Annual Scientific Session (5th) Abstracts,

DTIC Science & Technology

1983-01-01

cm ) for one hour. Extended survival of hamsters from VSV injection could be due to activated macropha- ges destroying Injected virus and perhaps...to increased anti-VSV antibody production. These results are consistent with our previous work with vaccinia virus (Bloelectromagnetics, In press...guinea pigs and cats reflect intracranial rever- berations of a pressure pulse induced within the brain. Results from single-unit and psychophysical

Minding the Gap? Young People's Accounts of Taking a Gap Year as a Form of Identity Work in Higher Education

ERIC Educational Resources Information Center

King, Andrew

2011-01-01

A Gap Year is a break in an educational career, principally taken between leaving school and beginning university. Previous research on the Gap Year has suggested it is a form of social class positioning or forum for undertaking transitions in identity during young adulthood. This paper extends this research into the context of higher education…

Fairness of prices, user fee policy and willingness to pay among visitors to a national forest

Treesearch

Jin Young Chung; Gerard T. Kyle; James F. Petrick; James D. Absher

2011-01-01

Imposing user fees in Nature-Based Tourism (NBT) contexts has been a controversial issue. Based on the notions of justice and fairness, this study extended previous work examining the relationship between attitudes toward user fees and spending support. In a proposed structural model of price fairness, fee spending support, and willingness to pay (WTP), this paper...

Saturation of the anisoplanatic error in horizontal imaging scenarios

NASA Astrophysics Data System (ADS)

Beck, Jeffrey; Bos, Jeremy P.

2017-09-01

We evaluate the piston-removed anisoplanatic error for smaller apertures imaging over long horizontal paths. Previous works have shown that the piston and tilt compensated anisoplanatic error saturates to values less than one squared radian. Under these conditions the definition of the isoplanatic angle is unclear. These works focused on nadir pointing telescope systems with aperture sizes between five meters and one half meter. We directly extend this work to horizontal imaging scenarios with aperture sizes smaller than one half meter. We assume turbulence is constant along the imaging path and that the ratio of the aperture size to the atmospheric coherence length is on the order of unity.

Model-independent limits and constraints on extended theories of gravity from cosmic reconstruction techniques

NASA Astrophysics Data System (ADS)

de la Cruz-Dombriz, Álvaro; Dunsby, Peter K. S.; Luongo, Orlando; Reverberi, Lorenzo

2016-12-01

The onset of dark energy domination depends on the particular gravitational theory driving the cosmic evolution. Model independent techniques are crucial to test the both the present ΛCDM cosmological paradigm and alternative theories, making the least possible number of assumptions about the Universe. In this paper we investigate whether cosmography is able to distinguish between different gravitational theories, by determining bounds on model parameters for three different extensions of General Relativity, namely quintessence, F(𝒯) and f(R) gravitational theories. We expand each class of theories in powers of redshift z around the present time, making no additional assumptions. This procedure is an extension of previous work and can be seen as the most general approach for testing extended theories of gravity through the use of cosmography. In the case of F(𝒯) and f(R) theories, we show that some assumptions on model parameters often made in previous works are superfluous or even unjustified. We use data from the Union 2.1 supernovae catalogue, baryonic acoustic oscillation data and H(z) differential age compilations, which probe cosmology on different scales of the cosmological evolution. We perform a Monte Carlo analysis using a Metropolis-Hastings algorithm with a Gelman-Rubin convergence criterion, reporting 1-σ and 2-σ confidence levels. To do so, we perform two distinct fits, assuming only data within z < 1 first and then without limitations in redshift. We obtain the corresponding numerical intervals in which coefficients span, and find that the data is compatible the ΛCDM limit of all three theories at the 1-σ level, while still compatible with quite a large portion of parameter space. We compare our results to the truncated ΛCDM paradigm, demonstrating that our bounds divert from the expectations of previous works, showing that the permitted regions of coefficients are significantly modified and in general widened with respect to values usually reported in the existing literature. Finally, we test the extended theories through the Bayesian selection criteria AIC and BIC.

Model-independent limits and constraints on extended theories of gravity from cosmic reconstruction techniques

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

Cruz-Dombriz, Álvaro de la; Dunsby, Peter K.S.; Luongo, Orlando

The onset of dark energy domination depends on the particular gravitational theory driving the cosmic evolution. Model independent techniques are crucial to test the both the present ΛCDM cosmological paradigm and alternative theories, making the least possible number of assumptions about the Universe. In this paper we investigate whether cosmography is able to distinguish between different gravitational theories, by determining bounds on model parameters for three different extensions of General Relativity, namely quintessence, F (Τ) and f ( R ) gravitational theories. We expand each class of theories in powers of redshift z around the present time, making no additionalmore » assumptions. This procedure is an extension of previous work and can be seen as the most general approach for testing extended theories of gravity through the use of cosmography. In the case of F (Τ) and f ( R ) theories, we show that some assumptions on model parameters often made in previous works are superfluous or even unjustified. We use data from the Union 2.1 supernovae catalogue, baryonic acoustic oscillation data and H ( z ) differential age compilations, which probe cosmology on different scales of the cosmological evolution. We perform a Monte Carlo analysis using a Metropolis-Hastings algorithm with a Gelman-Rubin convergence criterion, reporting 1-σ and 2-σ confidence levels. To do so, we perform two distinct fits, assuming only data within z < 1 first and then without limitations in redshift. We obtain the corresponding numerical intervals in which coefficients span, and find that the data is compatible the ΛCDM limit of all three theories at the 1-σ level, while still compatible with quite a large portion of parameter space. We compare our results to the truncated ΛCDM paradigm, demonstrating that our bounds divert from the expectations of previous works, showing that the permitted regions of coefficients are significantly modified and in general widened with respect to values usually reported in the existing literature. Finally, we test the extended theories through the Bayesian selection criteria AIC and BIC.« less

Generic Safety Requirements for Developing Safe Insulin Pump Software

PubMed Central

Zhang, Yi; Jetley, Raoul; Jones, Paul L; Ray, Arnab

2011-01-01

Background The authors previously introduced a highly abstract generic insulin infusion pump (GIIP) model that identified common features and hazards shared by most insulin pumps on the market. The aim of this article is to extend our previous work on the GIIP model by articulating safety requirements that address the identified GIIP hazards. These safety requirements can be validated by manufacturers, and may ultimately serve as a safety reference for insulin pump software. Together, these two publications can serve as a basis for discussing insulin pump safety in the diabetes community. Methods In our previous work, we established a generic insulin pump architecture that abstracts functions common to many insulin pumps currently on the market and near-future pump designs. We then carried out a preliminary hazard analysis based on this architecture that included consultations with many domain experts. Further consultation with domain experts resulted in the safety requirements used in the modeling work presented in this article. Results Generic safety requirements for the GIIP model are presented, as appropriate, in parameterized format to accommodate clinical practices or specific insulin pump criteria important to safe device performance. Conclusions We believe that there is considerable value in having the diabetes, academic, and manufacturing communities consider and discuss these generic safety requirements. We hope that the communities will extend and revise them, make them more representative and comprehensive, experiment with them, and use them as a means for assessing the safety of insulin pump software designs. One potential use of these requirements is to integrate them into model-based engineering (MBE) software development methods. We believe, based on our experiences, that implementing safety requirements using MBE methods holds promise in reducing design/implementation flaws in insulin pump development and evolutionary processes, therefore improving overall safety of insulin pump software. PMID:22226258

Exploring Expressive Vocabulary Variability in Two-Year-Olds: The Role of Working Memory.

PubMed

Newbury, Jayne; Klee, Thomas; Stokes, Stephanie F; Moran, Catherine

2015-12-01

This study explored whether measures of working memory ability contribute to the wide variation in 2-year-olds' expressive vocabulary skills. Seventy-nine children (aged 24-30 months) were assessed by using standardized tests of vocabulary and visual cognition, a processing speed measure, and behavioral measures of verbal working memory and phonological short-term memory. Strong correlations were observed between phonological short-term memory, verbal working memory, and expressive vocabulary. Speed of spoken word recognition showed a moderate significant correlation with expressive vocabulary. In a multivariate regression model for expressive vocabulary, the most powerful predictor was a measure of phonological short-term memory (accounting for 66% unique variance), followed by verbal working memory (6%), sex (2%), and age (1%). Processing speed did not add significant unique variance. These findings confirm previous research positing a strong role for phonological short-term memory in early expressive vocabulary acquisition. They also extend previous research in two ways. First, a unique association between verbal working memory and expressive vocabulary in 2-year-olds was observed. Second, processing speed was not a unique predictor of variance in expressive vocabulary when included alongside measures of working memory.

Molecular dynamics analysis of the influence of Coulomb and van der Waals interactions on the work of adhesion at the solid-liquid interface

NASA Astrophysics Data System (ADS)

Surblys, Donatas; Leroy, Frédéric; Yamaguchi, Yasutaka; Müller-Plathe, Florian

2018-04-01

We investigated the solid-liquid work of adhesion of water on a model silica surface by molecular dynamics simulations, where a methodology previously developed to determine the work of adhesion through thermodynamic integration was extended to a system with long-range electrostatic interactions between solid and liquid. In agreement with previous studies, the work of adhesion increased when the magnitude of the surface polarity was increased. On the other hand, we found that when comparing two systems with and without solid-liquid electrostatic interactions, which were set to have approximately the same total solid-liquid interfacial energy, former had a significantly smaller work of adhesion and a broader distribution in the interfacial energies, which has not been previously reported in detail. This was explained by the entropy contribution to the adhesion free energy; i.e., the former with a broader energy distribution had a larger interfacial entropy than the latter. While the entropy contribution to the work of adhesion has already been known, as a work of adhesion itself is free energy, these results indicate that, contrary to common belief, wetting behavior such as the contact angle is not only governed by the interfacial energy but also significantly affected by the interfacial entropy. Finally, a new interpretation of interfacial entropy in the context of solid-liquid energy variance was offered, from which a fast way to qualitatively estimate the work of adhesion was also presented.

Effects of prior cocaine self-administration on cognitive performance in female cynomolgus monkeys.

PubMed

Kromrey, Sarah A; Gould, Robert W; Nader, Michael A; Czoty, Paul W

2015-06-01

Cocaine use has been associated with cognitive impairments that may contribute to poor treatment outcomes. However, the degree to which these deficits extend into periods of abstinence has not been completely elucidated. This study tested whether prior experience self-administering cocaine affected acquisition of two cognitive tasks in 16 adult female cynomolgus monkeys. Seven monkeys had previously self-administered cocaine but had not had access to cocaine for 2 months at the start of this study. After monkeys were trained to respond on a touchscreen, associative learning and behavioral flexibility were assessed using a stimulus discrimination (SD) and reversal (SDR) task from the CANTAB battery. Performance on this task was monitored over the subsequent 3 months. Additionally, working memory was assessed with a delayed match-to-sample (DMS) task. Cocaine-naïve monkeys required fewer total trials and made fewer errors and omissions before acquiring the SD and SDR tasks compared with monkeys who had previously self-administered cocaine; two monkeys in the latter group did not acquire the task. However, this cognitive impairment dissipated over several months of exposure to the task. The number of sessions for touch training and delays required to establish a performance-based curve on the DMS task did not differ between groups. Results suggest that cocaine exposure can impair the ability to learn a novel task requiring behavioral inhibition and flexibility, even after an extended period of abstinence. However, this deficit did not extend to maintenance of the task or to acquisition of a working memory task.

The dose-response of Harshaw TLD-700H.

PubMed

Velbeck, K J; Luo, L Z; Ramlo, M J; Rotunda, J E

2006-01-01

Harshaw TLD-700H (7LiF:Mg,Cu,P) was previously characterised for low- to high-dose ranges from 1 microGy to 20 Gy. This paper describes the studies and results of dose-response and linearity at much higher doses. TLD-700H is a near perfect dosimetric material with near tissue equivalence, flat energy response, and the ability to measure beta, gamma and X rays. These new results extend the applicability of Harshaw TLD-700H into more dosimetric measurement environments. The simple glow curve structure provides insignificant fade, eliminating special oven preparation methods experienced by other materials. The work presented in this paper quantifies the performance of Harshaw TLD-700H in extended ranges.

Fluid Fe(1 - x)Hx under extreme conditions

NASA Astrophysics Data System (ADS)

Seclaman, Alexandra; Wilson, Hugh F.; Cohen, Ronald E.

We study the fluid Fe-H binary system using first principles molecular dynamics (FPMD) and a new FPMD-based method, CATS, in order to compute efficiently and accurately the equation of state of Fe-H fluids up to 5 TPa and 30,000K. We constructed GRBV-type LDA pseudopotentials for Fe and H with small rcuts in order to avoid pseudo-core overlap. In the liquid Fe regime we find good agreement with previous works, up to the pressures where data is available. In the high density regime of pure H we also find good agreement with previous results. Previous work has been focused on low Fe concentrations in metallic liquid H. We extend previous studies by investigating several intermediate Fe(1 - x)Hx liquid compositions, as well as metallic liquid H and Fe. Preliminary results indicate extreme compositional pressure effects under isothermic and isochoric conditions, 3.9 TPa difference between Fe and H at 20,000K. Thermal pressure effects are comparatively small, 0.12-0.15 TPa per 10,000K for H and Fe, respectively. Equations of state will be presented and fluid immiscibility will be discussed. This work has been supported by the ERC Advanced Grant ToMCaT and NSF and the Carnegie Institution.

Event-driven simulations of nonlinear integrate-and-fire neurons.

PubMed

Tonnelier, Arnaud; Belmabrouk, Hana; Martinez, Dominique

2007-12-01

Event-driven strategies have been used to simulate spiking neural networks exactly. Previous work is limited to linear integrate-and-fire neurons. In this note, we extend event-driven schemes to a class of nonlinear integrate-and-fire models. Results are presented for the quadratic integrate-and-fire model with instantaneous or exponential synaptic currents. Extensions to conductance-based currents and exponential integrate-and-fire neurons are discussed.

Relating Bond Angles of Dihalo- and Tetrahydro--Methanes, -Silanes, and -Germanes to Electronegativities

ERIC Educational Resources Information Center

Kirschenbaum, Louis J.; Ruekberg, Ben

2012-01-01

Our previous work correlated bond angles of group V and group VI hydrides (AH[subscript 3]E and AH[subscript 2]E[subscript 2], respectively, where E represents a lone electron pair) to the electronegativities of the atoms using the fraction of s character to relate the two. Here we have extended the correlation to the AH[subscript 2]X[subscript 2]…

Magnetic Resonance Characterization of Axonal Response to Spinal Cord Injury

DTIC Science & Technology

2011-10-01

Outcomes 6 Conclusions 6 References 6-29 Appendices Introduction During the first year we pursued studies of Magnetic Resonance q-space imaging...QSI) of the spinal cord and myelin imaging. The QSI studies extended our previous work establishing our ability to define the distribution of axon...Conventional MR imaging of the central nervous systems studies water protons exclusively. Although other compounds, such a lipid and proteins, have

Optimization of Extended Relational Database Systems

DTIC Science & Technology

1986-07-23

control functions are integrated into a single system in a homogeneoua way. As a first exam - ple, consider previous work in supporting various semantic...sizes are reduced and, wnk? quently, the number of materializations that will be needed is aba lower. For exam - pie, in the above query tuple...retrieve (EMP.name) where EMP hobbies instrument = ’ violin ’ When the various entries in the hobbies field are materialized, only those queries that

Fatal Passenger Vehicle Crashes with At Least 1 Driver Younger than 15 Years: A Fatality Analysis Reporting System Study

ERIC Educational Resources Information Center

Frisch, Larry; Plessinger, Alexander

2007-01-01

Context: A small number of fatalities continue to occur due to motor vehicle crashes on highways in which at least 1 passenger vehicle (automobile, van, or small truck) is driven by a child younger than 15 years. Purpose: The purpose of this study was to extend previous work suggesting that such crashes occur frequently in the Southern states and…

The symbolic computation of series solutions to ordinary differential equations using trees (extended abstract)

NASA Technical Reports Server (NTRS)

Grossman, Robert

1991-01-01

Algorithms previously developed by the author give formulas which can be used for the efficient symbolic computation of series expansions to solutions of nonlinear systems of ordinary differential equations. As a by product of this analysis, formulas are derived which relate to trees to the coefficients of the series expansions, similar to the work of Leroux and Viennot, and Lamnabhi, Leroux and Viennot.

Dust Devils on Mars: Effects of Surface Roughness on Particle Threshold

NASA Technical Reports Server (NTRS)

Neakrase, Lynn D.; Greeley, Ronald; Iversen, James D.; Balme, Matthew L.; Foley, Daniel J.; Eddlemon, Eric E.

2005-01-01

Dust devils have been proposed as effective mechanisms for lofting large quantities of dust into the martian atmosphere. Previous work showed that vortices lift dust more easily than simple boundary layer winds. The aim of this study is to determine experimentally the effects of non-erodable roughness elements on vortex particle threshold through laboratory simulations of natural surfaces. Additional information is included in the original extended abstract.

Unified Models of Turbulence and Nonlinear Wave Evolution in the Extended Solar Corona and Solar Wind

NASA Technical Reports Server (NTRS)

Wagner, William (Technical Monitor); Cranmer, Steven R.

2005-01-01

The paper discusses the following: 1. No-cost Extension. The no-cost extension is required to complete the work on the unified model codes (both hydrodynamic and kinetic Monte Carlo) as described in the initial proposal and previous annual reports. 2. Scientific Accomplishments during the Report Period. We completed a comprehensive model of Alfvtn wave reflection that spans the full distance from the photosphere to the distant heliosphere. 3. Comparison of Accomplishments with Proposed Goals. The proposal contained two specific objectives for Year 3: (1) to complete the unified model code, and (2) to apply it to various kinds of coronal holes (and polar plumes within coronal holes). Although the anticipated route toward these two final goals has changed (see accomplishments 2a and 2b above), they remain the major milestones for the extended period of performance. Accomplishments la and IC were necessary prerequisites for the derivation of "physically relevant transport and mode-coupling terms" for the unified model codes (as stated in the proposal Year 3 goals). We have fulfilled the proposed "core work" to study 4 general types of physical processes; in previous years we studied turbulence, mode coupling (Le., non-WKB reflection), and kinetic wave damping, and accomplishment lb provides the fourth topic: nonlinear steepening.

Active Listening in a Bat Cocktail Party: Adaptive Echolocation and Flight Behaviors of Big Brown Bats, Eptesicus fuscus, Foraging in a Cluttered Acoustic Environment.

PubMed

Warnecke, Michaela; Chiu, Chen; Engelberg, Jonathan; Moss, Cynthia F

2015-09-01

In their natural environment, big brown bats forage for small insects in open spaces, as well as in vegetation and in the presence of acoustic clutter. While searching and hunting for prey, bats experience sonar interference, not only from densely cluttered environments, but also from calls of conspecifics foraging in close proximity. Previous work has shown that when two bats compete for a single prey item in a relatively open environment, one of the bats may go silent for extended periods of time, which can serve to minimize sonar interference between conspecifics. Additionally, pairs of big brown bats have been shown to adjust frequency characteristics of their vocalizations to avoid acoustic interference in echo processing. In this study, we extended previous work by examining how the presence of conspecifics and environmental clutter influence the bat's echolocation behavior. By recording multichannel audio and video data of bats engaged in insect capture in open and cluttered spaces, we quantified the bats' vocal and flight behaviors. Big brown bats flew individually and in pairs in an open and cluttered room, and the results of this study shed light on the different strategies that this species employs to negotiate a complex and dynamic environment. © 2015 S. Karger AG, Basel.

The role of strigolactones and ethylene in disease caused by Pythium irregulare.

PubMed

Blake, Sara N; Barry, Karen M; Gill, Warwick M; Reid, James B; Foo, Eloise

2016-06-01

Plant hormones play key roles in defence against pathogen attack. Recent work has begun to extend this role to encompass not just the traditional disease/stress hormones, such as ethylene, but also growth-promoting hormones. Strigolactones (SLs) are the most recently defined group of plant hormones with important roles in plant-microbe interactions, as well as aspects of plant growth and development, although the knowledge of their role in plant-pathogen interactions is extremely limited. The oomycete Pythium irregulare is a poorly controlled pathogen of many crops. Previous work has indicated an important role for ethylene in defence against this oomycete. We examined the role of ethylene and SLs in response to this pathogen in pea (Pisum sativum L.) at the molecular and whole-plant levels using a set of well-characterized hormone mutants, including an ethylene-insensitive ein2 mutant and SL-deficient and insensitive mutants. We identified a key role for ethylene signalling in specific cell types that reduces pathogen invasion, extending the work carried out in other species. However, we found no evidence that SL biosynthesis or response influences the interaction of pea with P. irregulare or that synthetic SL influences the growth or hyphal branching of the oomycete in vitro. Future work should seek to extend our understanding of the role of SLs in other plant interactions, including with other fungal, bacterial and viral pathogens, nematodes and insect pests. © 2015 BSPP AND JOHN WILEY & SONS LTD.

Dependence of Adaptive Cross-correlation Algorithm Performance on the Extended Scene Image Quality

NASA Technical Reports Server (NTRS)

Sidick, Erkin

2008-01-01

Recently, we reported an adaptive cross-correlation (ACC) algorithm to estimate with high accuracy the shift as large as several pixels between two extended-scene sub-images captured by a Shack-Hartmann wavefront sensor. It determines the positions of all extended-scene image cells relative to a reference cell in the same frame using an FFT-based iterative image-shifting algorithm. It works with both point-source spot images as well as extended scene images. We have demonstrated previously based on some measured images that the ACC algorithm can determine image shifts with as high an accuracy as 0.01 pixel for shifts as large 3 pixels, and yield similar results for both point source spot images and extended scene images. The shift estimate accuracy of the ACC algorithm depends on illumination level, background, and scene content in addition to the amount of the shift between two image cells. In this paper we investigate how the performance of the ACC algorithm depends on the quality and the frequency content of extended scene images captured by a Shack-Hatmann camera. We also compare the performance of the ACC algorithm with those of several other approaches, and introduce a failsafe criterion for the ACC algorithm-based extended scene Shack-Hatmann sensors.

Investigating the Receptive-Expressive Vocabulary Profile in Children with Idiopathic ASD and Comorbid ASD and Fragile X Syndrome.

PubMed

Haebig, Eileen; Sterling, Audra

2017-02-01

Previous work has noted that some children with autism spectrum disorder (ASD) display weaknesses in receptive vocabulary relative to expressive vocabulary abilities. The current study extended previous work by examining the receptive-expressive vocabulary profile in boys with idiopathic ASD and boys with concomitant ASD and fragile X syndrome (ASD + FXS). On average, boys with ASD + FXS did not display the same atypical receptive-expressive profile as boys with idiopathic ASD. Notably, there was variation in vocabulary abilities and profiles in both groups. Although we did not identify predictors of receptive-expressive differences, we demonstrated that nonverbal IQ and expressive vocabulary positively predicted concurrent receptive vocabulary knowledge and receptive vocabulary predicted expressive vocabulary. We discuss areas of overlap and divergence in subgroups of ASD.

Investigating the Receptive-Expressive Vocabulary Profile in Children with Idiopathic ASD and Comorbid ASD and Fragile X Syndrome

PubMed Central

Sterling, Audra

2016-01-01

Previous work has noted that some children with autism spectrum disorder (ASD) display weaknesses in receptive vocabulary relative to expressive vocabulary abilities. The current study extended previous work by examining the receptive-expressive vocabulary profile in boys with idiopathic ASD and boys with concomitant ASD and fragile X syndrome (ASD + FXS). On average, boys with ASD + FXS did not display the same atypical receptive-expressive profile as boys with idiopathic ASD. Notably, there was variation in vocabulary abilities and profiles in both groups. Although we did not identify predictors of receptive-expressive differences, we demonstrated that nonverbal IQ and expressive vocabulary positively predicted concurrent receptive vocabulary knowledge and receptive vocabulary predicted expressive vocabulary. We discuss areas of overlap and divergence in subgroups of ASD. PMID:27796729

Nonlinear regimes on polygonal hydraulic jumps

NASA Astrophysics Data System (ADS)

Rojas, Nicolas

2016-11-01

This work extends previous leading and higher order results on the polygonal hydraulic jump in the framework of inertial lubrication theory. The rotation of steady polygonal jumps is observed in the transition from one wavenumber to the next one, induced by a change in height of an external obstacle near the outer edge. In a previous publication, the study of stationary polygons is considered under the assumption that the reference frame rotates with the polygons when the number of corners change, in order to preserve their orientation. In this research work I provide a Hamiltonian approach and the stability analysis of the nonlinear oscillator that describe the polygonal structures at the jump interface, in addition to a perturbation method that enables to explain, for instance, the diversity of patterns found in experiments. GRASP, Institute of Physics, University of Liege, Belgium.

The attentional drift-diffusion model extends to simple purchasing decisions.

PubMed

Krajbich, Ian; Lu, Dingchao; Camerer, Colin; Rangel, Antonio

2012-01-01

How do we make simple purchasing decisions (e.g., whether or not to buy a product at a given price)? Previous work has shown that the attentional drift-diffusion model (aDDM) can provide accurate quantitative descriptions of the psychometric data for binary and trinary value-based choices, and of how the choice process is guided by visual attention. Here we extend the aDDM to the case of purchasing decisions, and test it using an eye-tracking experiment. We find that the model also provides a reasonably accurate quantitative description of the relationship between choice, reaction time, and visual fixations using parameters that are very similar to those that best fit the previous data. The only critical difference is that the choice biases induced by the fixations are about half as big in purchasing decisions as in binary choices. This suggests that a similar computational process is used to make binary choices, trinary choices, and simple purchasing decisions.

The Attentional Drift-Diffusion Model Extends to Simple Purchasing Decisions

PubMed Central

Krajbich, Ian; Lu, Dingchao; Camerer, Colin; Rangel, Antonio

2012-01-01

How do we make simple purchasing decisions (e.g., whether or not to buy a product at a given price)? Previous work has shown that the attentional drift-diffusion model (aDDM) can provide accurate quantitative descriptions of the psychometric data for binary and trinary value-based choices, and of how the choice process is guided by visual attention. Here we extend the aDDM to the case of purchasing decisions, and test it using an eye-tracking experiment. We find that the model also provides a reasonably accurate quantitative description of the relationship between choice, reaction time, and visual fixations using parameters that are very similar to those that best fit the previous data. The only critical difference is that the choice biases induced by the fixations are about half as big in purchasing decisions as in binary choices. This suggests that a similar computational process is used to make binary choices, trinary choices, and simple purchasing decisions. PMID:22707945

Quantum dynamics calculations using symmetrized, orthogonal Weyl-Heisenberg wavelets with a phase space truncation scheme. III. Representations and calculations.

PubMed

Poirier, Bill; Salam, A

2004-07-22

In a previous paper [J. Theo. Comput. Chem. 2, 65 (2003)], one of the authors (B.P.) presented a method for solving the multidimensional Schrodinger equation, using modified Wilson-Daubechies wavelets, and a simple phase space truncation scheme. Unprecedented numerical efficiency was achieved, enabling a ten-dimensional calculation of nearly 600 eigenvalues to be performed using direct matrix diagonalization techniques. In a second paper [J. Chem. Phys. 121, 1690 (2004)], and in this paper, we extend and elaborate upon the previous work in several important ways. The second paper focuses on construction and optimization of the wavelength functions, from theoretical and numerical viewpoints, and also examines their localization. This paper deals with their use in representations and eigenproblem calculations, which are extended to 15-dimensional systems. Even higher dimensionalities are possible using more sophisticated linear algebra techniques. This approach is ideally suited to rovibrational spectroscopy applications, but can be used in any context where differential equations are involved.

Combining MEDLINE and publisher data to create parallel corpora for the automatic translation of biomedical text

PubMed Central

2013-01-01

Background Most of the institutional and research information in the biomedical domain is available in the form of English text. Even in countries where English is an official language, such as the United States, language can be a barrier for accessing biomedical information for non-native speakers. Recent progress in machine translation suggests that this technique could help make English texts accessible to speakers of other languages. However, the lack of adequate specialized corpora needed to train statistical models currently limits the quality of automatic translations in the biomedical domain. Results We show how a large-sized parallel corpus can automatically be obtained for the biomedical domain, using the MEDLINE database. The corpus generated in this work comprises article titles obtained from MEDLINE and abstract text automatically retrieved from journal websites, which substantially extends the corpora used in previous work. After assessing the quality of the corpus for two language pairs (English/French and English/Spanish) we use the Moses package to train a statistical machine translation model that outperforms previous models for automatic translation of biomedical text. Conclusions We have built translation data sets in the biomedical domain that can easily be extended to other languages available in MEDLINE. These sets can successfully be applied to train statistical machine translation models. While further progress should be made by incorporating out-of-domain corpora and domain-specific lexicons, we believe that this work improves the automatic translation of biomedical texts. PMID:23631733

Fluctuation removal around spectral and temporal constancy limits via use of an extended space expectation value weight function for singular quantum systems

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

Kalay, Berfin; Demiralp, Metin

2015-03-10

This work is a new extension to our a very recent work whose paper will appear in the proceedings of a very recent international conference. What we have done in the previous work is the use of a weight operator to suppress the singularities causing nonexistence of some of temporal Maclaurin expansion coefficients. The weight operator has been constructed in such a way that certain number of expectation values of position operator’s first positive integer powers with and without the chosen weight operator match. Therein this match has not been considered for the momentum operator’s corresponding power expectation values andmore » a finite linear combination of the spatial variable’s first reciprocal powers has been used in the construction of the weight operator. Here, that approach is extended to the case where matches for both position and momentum operators are considered and the weight operator involves finite linear combinations of the spatial variable’s both positive integer powers and their reciprocals.« less

A century of transitions in New York City's measles dynamics.

PubMed

Hempel, Karsten; Earn, David J D

2015-05-06

Infectious diseases spreading in a human population occasionally exhibit sudden transitions in their qualitative dynamics. Previous work has successfully predicted such transitions in New York City's historical measles incidence using the seasonally forced susceptible-infectious-recovered (SIR) model. This work relied on a dataset spanning 45 years (1928-1973), which we have extended to 93 years (1891-1984). We identify additional dynamical transitions in the longer dataset and successfully explain them by analysing attractors and transients of the same mechanistic epidemiological model. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Creep, Fatigue and Environmental Interactions and Their Effect on Crack Growth in Superalloys

NASA Technical Reports Server (NTRS)

Telesman, J.; Gabb, T. P.; Ghosn, L. J.; Smith, T.

2017-01-01

Complex interactions of creep/fatigue/environment control dwell fatigue crack growth (DFCG) in superalloys. Crack tip stress relaxation during dwells significantly changes the crack driving force and influence DFCG. Linear Elastic Fracture Mechanics, Kmax, parameter unsuitable for correlating DFCG behavior due to extensive visco-plastic deformation. Magnitude of remaining crack tip axial stresses controls DFCG resistance due to the brittle-intergranular nature of the crack growth process. Proposed a new empirical parameter, Ksrf, which incorporates visco-plastic evolution of the magnitude of remaining crack tip stresses. Previous work performed at 704C, extend the work to 760C.

Combustion-acoustic stability analysis for premixed gas turbine combustors

NASA Technical Reports Server (NTRS)

Darling, Douglas; Radhakrishnan, Krishnan; Oyediran, Ayo; Cowan, Lizabeth

1995-01-01

Lean, prevaporized, premixed combustors are susceptible to combustion-acoustic instabilities. A model was developed to predict eigenvalues of axial modes for combustion-acoustic interactions in a premixed combustor. This work extends previous work by including variable area and detailed chemical kinetics mechanisms, using the code LSENS. Thus the acoustic equations could be integrated through the flame zone. Linear perturbations were made of the continuity, momentum, energy, chemical species, and state equations. The qualitative accuracy of our approach was checked by examining its predictions for various unsteady heat release rate models. Perturbations in fuel flow rate are currently being added to the model.

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

Li, Yan-Rong; Wang, Jian-Min; Bai, Jin-Ming, E-mail: liyanrong@mail.ihep.ac.cn

Broad emission lines of active galactic nuclei stem from a spatially extended region (broad-line region, BLR) that is composed of discrete clouds and photoionized by the central ionizing continuum. The temporal behaviors of these emission lines are blurred echoes of continuum variations (i.e., reverberation mapping, RM) and directly reflect the structures and kinematic information of BLRs through the so-called transfer function (also known as the velocity-delay map). Based on the previous works of Rybicki and Press and Zu et al., we develop an extended, non-parametric approach to determine the transfer function for RM data, in which the transfer function ismore » expressed as a sum of a family of relatively displaced Gaussian response functions. Therefore, arbitrary shapes of transfer functions associated with complicated BLR geometry can be seamlessly included, enabling us to relax the presumption of a specified transfer function frequently adopted in previous studies and to let it be determined by observation data. We formulate our approach in a previously well-established framework that incorporates the statistical modeling of continuum variations as a damped random walk process and takes into account long-term secular variations which are irrelevant to RM signals. The application to RM data shows the fidelity of our approach.« less

Examining the Roles of Reasoning and Working Memory in Predicting Casual Game Performance across Extended Gameplay.

PubMed

Kranz, Michael B; Baniqued, Pauline L; Voss, Michelle W; Lee, Hyunkyu; Kramer, Arthur F

2017-01-01

The variety and availability of casual video games presents an exciting opportunity for applications such as cognitive training. Casual games have been associated with fluid abilities such as working memory (WM) and reasoning, but the importance of these cognitive constructs in predicting performance may change across extended gameplay and vary with game structure. The current investigation examined the relationship between cognitive abilities and casual game performance over time by analyzing first and final session performance over 4-5 weeks of game play. We focused on two groups of subjects who played different types of casual games previously shown to relate to WM and reasoning when played for a single session: (1) puzzle-based games played adaptively across sessions and (2) speeded switching games played non-adaptively across sessions. Reasoning uniquely predicted first session casual game scores for both groups and accounted for much of the relationship with WM. Furthermore, over time, WM became uniquely important for predicting casual game performance for the puzzle-based adaptive games but not for the speeded switching non-adaptive games. These results extend the burgeoning literature on cognitive abilities involved in video games by showing differential relationships of fluid abilities across different game types and extended play. More broadly, the current study illustrates the usefulness of using multiple cognitive measures in predicting performance, and provides potential directions for game-based cognitive training research.

Examining the Roles of Reasoning and Working Memory in Predicting Casual Game Performance across Extended Gameplay

PubMed Central

Kranz, Michael B.; Baniqued, Pauline L.; Voss, Michelle W.; Lee, Hyunkyu; Kramer, Arthur F.

2017-01-01

The variety and availability of casual video games presents an exciting opportunity for applications such as cognitive training. Casual games have been associated with fluid abilities such as working memory (WM) and reasoning, but the importance of these cognitive constructs in predicting performance may change across extended gameplay and vary with game structure. The current investigation examined the relationship between cognitive abilities and casual game performance over time by analyzing first and final session performance over 4–5 weeks of game play. We focused on two groups of subjects who played different types of casual games previously shown to relate to WM and reasoning when played for a single session: (1) puzzle-based games played adaptively across sessions and (2) speeded switching games played non-adaptively across sessions. Reasoning uniquely predicted first session casual game scores for both groups and accounted for much of the relationship with WM. Furthermore, over time, WM became uniquely important for predicting casual game performance for the puzzle-based adaptive games but not for the speeded switching non-adaptive games. These results extend the burgeoning literature on cognitive abilities involved in video games by showing differential relationships of fluid abilities across different game types and extended play. More broadly, the current study illustrates the usefulness of using multiple cognitive measures in predicting performance, and provides potential directions for game-based cognitive training research. PMID:28326042

Generating human-like movements on an anthropomorphic robot using an interior point method

NASA Astrophysics Data System (ADS)

Costa e Silva, E.; Araújo, J. P.; Machado, D.; Costa, M. F.; Erlhagen, W.; Bicho, E.

2013-10-01

In previous work we have presented a model for generating human-like arm and hand movements on an anthropomorphic robot involved in human-robot collaboration tasks. This model was inspired by the Posture-Based Motion-Planning Model of human movements. Numerical results and simulations for reach-to-grasp movements with two different grip types have been presented previously. In this paper we extend our model in order to address the generation of more complex movement sequences which are challenged by scenarios cluttered with obstacles. The numerical results were obtained using the IPOPT solver, which was integrated in our MATLAB simulator of an anthropomorphic robot.

The increased financial burden of further proposed orthopaedic resident work-hour reductions.

PubMed

Kamath, Atul F; Baldwin, Keith; Meade, Lauren K; Powell, Adam C; Mehta, Samir

2011-04-06

Increased funding for graduate medical education was not provided during implementation of the eighty-hour work week. Many teaching hospitals responded to decreased work hours by hiring physician extenders to maintain continuity of care. Recent proposals have included a further decrease in work hours to a total of fifty-six hours. The goal of this study was to determine the direct cost related to a further reduction in orthopaedic-resident work hours. A survey was delivered to 152 residency programs to determine the number of full-time equivalent (FTE) physician extenders hired after implementation of the eighty-hour work-week restriction. Thirty-six programs responded (twenty-nine university-based programs and seven community-based programs), encompassing 1021 residents. Previous published data were used to determine the change in resident work hours with implementation of the eighty-hour regulation. A ratio between change in full-time equivalent staff per resident and number of reduced hours was used to determine the cost of the proposed further decrease. After implementation of the eighty-hour work week, the average reduction among orthopaedic residents was approximately five work hours per week. One hundred and forty-three physician extenders (equal to 142 full-time equivalent units) were hired to meet compliance at a frequency-weighted average cost of $96,000 per full-time equivalent unit. A further reduction to fifty-six hours would increase the cost by $64,000 per resident. With approximately 3200 orthopaedic residents nationwide, sensitivity analyses (based on models of eighty and seventy-three-hour work weeks) demonstrate that the increased cost would be between $147 million and $208 million per fiscal year. For each hourly decrease in weekly work hours, the cost is $8 million to $12 million over the course of a fiscal year. Mandated reductions in resident work hours are a costly proposition, without a clear decrease in adverse events. The federal government should consider these data prior to initiating unfunded work-hour mandates, as further reductions in resident work hours may make resident education financially unsustainable. © 2011 by the Journal of Bone and Joint Surgery, Incorporated

A new version of Visual tool for estimating the fractal dimension of images

NASA Astrophysics Data System (ADS)

Grossu, I. V.; Felea, D.; Besliu, C.; Jipa, Al.; Bordeianu, C. C.; Stan, E.; Esanu, T.

2010-04-01

This work presents a new version of a Visual Basic 6.0 application for estimating the fractal dimension of images (Grossu et al., 2009 [1]). The earlier version was limited to bi-dimensional sets of points, stored in bitmap files. The application was extended for working also with comma separated values files and three-dimensional images. New version program summaryProgram title: Fractal Analysis v02 Catalogue identifier: AEEG_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEG_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 9999 No. of bytes in distributed program, including test data, etc.: 4 366 783 Distribution format: tar.gz Programming language: MS Visual Basic 6.0 Computer: PC Operating system: MS Windows 98 or later RAM: 30 M Classification: 14 Catalogue identifier of previous version: AEEG_v1_0 Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 1999 Does the new version supersede the previous version?: Yes Nature of problem: Estimating the fractal dimension of 2D and 3D images. Solution method: Optimized implementation of the box-counting algorithm. Reasons for new version:The previous version was limited to bitmap image files. The new application was extended in order to work with objects stored in comma separated values (csv) files. The main advantages are: Easier integration with other applications (csv is a widely used, simple text file format); Less resources consumed and improved performance (only the information of interest, the "black points", are stored); Higher resolution (the points coordinates are loaded into Visual Basic double variables [2]); Possibility of storing three-dimensional objects (e.g. the 3D Sierpinski gasket). In this version the optimized box-counting algorithm [1] was extended to the three-dimensional case. Summary of revisions:The application interface was changed from SDI (single document interface) to MDI (multi-document interface). One form was added in order to provide a graphical user interface for the new functionalities (fractal analysis of 2D and 3D images stored in csv files). Additional comments: User friendly graphical interface; Easy deployment mechanism. Running time: In the first approximation, the algorithm is linear. References:[1] I.V. Grossu, C. Besliu, M.V. Rusu, Al. Jipa, C.C. Bordeianu, D. Felea, Comput. Phys. Comm. 180 (2009) 1999-2001.[2] F. Balena, Programming Microsoft Visual Basic 6.0, Microsoft Press, US, 1999.

Structure of 98Ru in the IBA-2 interacting boson model

NASA Astrophysics Data System (ADS)

Giannatiempo, A.

2017-10-01

The 98Ru structure has been investigated in the framework of the IBA-2 model, extending previous works to exploit the whole set of new spectroscopic data. The occurrence of states of mixed symmetry character in the proton and neutron degrees of freedom is of prominent importance in enlightening the structure of this nucleus, which displays features close to those of the Uπ ,ν(5) limit of the model.

Interface Technology for Geometrically Nonlinear Analysis of Multiple Connected Subdomains

NASA Technical Reports Server (NTRS)

Ransom, Jonathan B.

1997-01-01

Interface technology for geometrically nonlinear analysis is presented and demonstrated. This technology is based on an interface element which makes use of a hybrid variational formulation to provide for compatibility between independently modeled connected subdomains. The interface element developed herein extends previous work to include geometric nonlinearity and to use standard linear and nonlinear solution procedures. Several benchmark nonlinear applications of the interface technology are presented and aspects of the implementation are discussed.

The Influence of Atmosphere-Ocean Interaction on MJO Development and Propagation

DTIC Science & Technology

2014-09-30

evaluate modeling results and process studies. The field phase of this project is associated with DYNAMO , which is the US contribution to the...influence on ocean temperature 4. Extended run for DYNAMO with high vertical resolution NCOM RESULTS Summary of project results The work funded...model experiments of the November 2011 MJO – the strongest MJO episode observed during the DYNAMO . The previous conceptual model that was based on TOGA

On-line implementation of nonlinear parameter estimation for the Space Shuttle main engine

NASA Technical Reports Server (NTRS)

Buckland, Julia H.; Musgrave, Jeffrey L.; Walker, Bruce K.

1992-01-01

We investigate the performance of a nonlinear estimation scheme applied to the estimation of several parameters in a performance model of the Space Shuttle Main Engine. The nonlinear estimator is based upon the extended Kalman filter which has been augmented to provide estimates of several key performance variables. The estimated parameters are directly related to the efficiency of both the low pressure and high pressure fuel turbopumps. Decreases in the parameter estimates may be interpreted as degradations in turbine and/or pump efficiencies which can be useful measures for an online health monitoring algorithm. This paper extends previous work which has focused on off-line parameter estimation by investigating the filter's on-line potential from a computational standpoint. ln addition, we examine the robustness of the algorithm to unmodeled dynamics. The filter uses a reduced-order model of the engine that includes only fuel-side dynamics. The on-line results produced during this study are comparable to off-line results generated previously. The results show that the parameter estimates are sensitive to dynamics not included in the filter model. Off-line results using an extended Kalman filter with a full order engine model to address the robustness problems of the reduced-order model are also presented.

Physiological and psychological impacts of extended work hours in logging operations

Treesearch

Dana Mitchell; Tom Gallagher

2007-01-01

A study was initiated in 2006 to develop an understanding of the considerations of using extended work hours in the logging industry in the southeastern United States. Through semistructured interviews, it was obvious that loggers were individually creating ways of successfully implementing extended working hours without understanding the impacts that extended working...

Laser-driven magnetic reconnection in the multi-plasmoid regime

NASA Astrophysics Data System (ADS)

Totorica, Samuel; Abel, Tom; Fiuza, Frederico

2017-10-01

Magnetic reconnection is a promising candidate mechanism for accelerating the nonthermal particles associated with explosive astrophysical phenomena. Laboratory experiments are starting to probe multi-plasmoid regimes of relevance for particle acceleration. We have performed two- and three-dimensional particle-in-cell (PIC) simulations to explore particle acceleration for parameters relevant to laser-driven reconnection experiments. We have extended our previous work to explore particle acceleration in larger system sizes. Our results show the transition to plasmoid-dominated acceleration associated with the merging and contraction of plasmoids that further extend the maximum energy of the power-law tail of the particle distribution. Furthermore, we have modeled Coulomb collisions and will discuss the influence of collisionality on the plasmoid formation, dynamics, and particle acceleration.

Early warning signal for interior crises in excitable systems.

PubMed

Karnatak, Rajat; Kantz, Holger; Bialonski, Stephan

2017-10-01

The ability to reliably predict critical transitions in dynamical systems is a long-standing goal of diverse scientific communities. Previous work focused on early warning signals related to local bifurcations (critical slowing down) and nonbifurcation-type transitions. We extend this toolbox and report on a characteristic scaling behavior (critical attractor growth) which is indicative of an impending global bifurcation, an interior crisis in excitable systems. We demonstrate our early warning signal in a conceptual climate model as well as in a model of coupled neurons known to exhibit extreme events. We observed critical attractor growth prior to interior crises of chaotic as well as strange-nonchaotic attractors. These observations promise to extend the classes of transitions that can be predicted via early warning signals.

Development of a Bio-Equivalent Ultraviolet Dosimeter to Monitor the Capacity for Vitamin D Synthesis of Sunlight Final Report CRADA No. TC02086.0

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

Smith, C. F.; Wood, D.

This project represents a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and Rhyolite Technology Group, Inc. (Rhyolite) to develop concepts and designs for a consumer ultraviolet (UV) biodosimeter based on the human biochemistry of Vitamin D synthesis. Rhyolite was established to engage in product development, licensing and consulting for the manufacture and supply of new products worldwide. Rhyolite worked jointly with LLNL and the Kiev Institute of Physics (KIP) in Ukraine to leverage previously developed UV sensor technologies by extending the previous work into commercially viable products. The projectmore » consisted primarily of the scientific, engineering and business activities needed to develop the UV bio-dosimeter for applications that include health and industrial measurement of ultraviolet radiation.« less

Lifetime Prevalence of Investigating Child Maltreatment Among US Children.

PubMed

Kim, Hyunil; Wildeman, Christopher; Jonson-Reid, Melissa; Drake, Brett

2017-02-01

To estimate the lifetime prevalence of official investigations for child maltreatment among children in the United States. We used the National Child Abuse and Neglect Data System Child Files (2003-2014) and Census data to develop synthetic cohort life tables to estimate the cumulative prevalence of reported childhood maltreatment. We extend previous work, which explored only confirmed rates of maltreatment, and we add new estimations of maltreatment by subtype, age, and ethnicity. We estimate that 37.4% of all children experience a child protective services investigation by age 18 years. Consistent with previous literature, we found a higher rate for African American children (53.0%) and the lowest rate for Asians/Pacific Islanders (10.2%). Child maltreatment investigations are more common than is generally recognized when viewed across the lifespan. Building on other recent work, our data suggest a critical need for increased preventative and treatment resources in the area of child maltreatment.

Fermi Blobs and the Symplectic Camel: A Geometric Picture of Quantum States

NASA Astrophysics Data System (ADS)

Gossona, Maurice A. De

We have explained in previous work the correspondence between the standard squeezed coherent states of quantum mechanics, and quantum blobs, which are the smallest phase space units compatible with the uncertainty principle of quantum mechanics and having the symplectic group as a group of symmetries. In this work, we discuss the relation between quantum blobs and a certain level set (which we call "Fermi blob") introduced by Enrico Fermi in 1930. Fermi blobs allows us to extend our previous results not only to the excited states of the generalized harmonic oscillator in n dimensions, but also to arbitrary quadratic Hamiltonians. As is the case for quantum blobs, we can evaluate Fermi blobs using a topological notion, related to the uncertainty principle, the symplectic capacity of a phase space set. The definition of this notion is made possible by Gromov's symplectic non-squeezing theorem, nicknamed the "principle of the symplectic camel".

Teaching for All? Teach For America’s Effects across the Distribution of Student Achievement

PubMed Central

Penner, Emily K.

2016-01-01

This paper examines the effect of Teach For America (TFA) on the distribution of student achievement in elementary school. It extends previous research by estimating quantile treatment effects (QTE) to examine how student achievement in TFA and non-TFA classrooms differs across the broader distribution of student achievement. It also updates prior distributional work on TFA by correcting for previously unidentified missing data and estimating unconditional, rather than conditional QTE. Consistent with previous findings, results reveal a positive impact of TFA teachers across the distribution of math achievement. In reading, however, relative to veteran non-TFA teachers, students at the bottom of the reading distribution score worse in TFA classrooms, and students in the upper half of the distribution perform better. PMID:27668032

A Moving Mesh Finite Element Algorithm for Singular Problems in Two and Three Space Dimensions

NASA Astrophysics Data System (ADS)

Li, Ruo; Tang, Tao; Zhang, Pingwen

2002-04-01

A framework for adaptive meshes based on the Hamilton-Schoen-Yau theory was proposed by Dvinsky. In a recent work (2001, J. Comput. Phys.170, 562-588), we extended Dvinsky's method to provide an efficient moving mesh algorithm which compared favorably with the previously proposed schemes in terms of simplicity and reliability. In this work, we will further extend the moving mesh methods based on harmonic maps to deal with mesh adaptation in three space dimensions. In obtaining the variational mesh, we will solve an optimization problem with some appropriate constraints, which is in contrast to the traditional method of solving the Euler-Lagrange equation directly. The key idea of this approach is to update the interior and boundary grids simultaneously, rather than considering them separately. Application of the proposed moving mesh scheme is illustrated with some two- and three-dimensional problems with large solution gradients. The numerical experiments show that our methods can accurately resolve detail features of singular problems in 3D.

Retraction Assembly for Space Shuttle Extended Nose Landing Gear

NASA Technical Reports Server (NTRS)

Files, Bradley S.; Nicholson, Leonard S. (Technical Monitor)

2000-01-01

As part of a project to encourage the use of shape memory alloy actuators for space actuators, this mechanism uses a nitinol ribbon to provide the necessary motion to help retract the proposed extended nose landing gear (ENLG) for the space shuttle. Initial proof-of-concept design of the ENLG did not include the ability to retract the gear automatically. One proposed actuator for this purpose was designed at Johnson Space Center and uses resistive heating to rotate the ribbon around a cylinder. This rotation then allows the assembly to pull down a wedge that is used to hold the landing gear strut in place, thus returning the landing gear to its previous height before extension. The presentation will follow the design of this assembly from working with the nitinol ribbon to providing mechanical connections and allowing minimal friction for motion of three wraps around a cylinder. Also to be presented is preliminary work on design of a shape memory alloy gripper, a design project to demonstrate uses of NiTi.

The Effects of Rotation on the Main-sequence Turnoff of Intermediate-age Massive Star Clusters

NASA Astrophysics Data System (ADS)

Yang, Wuming; Bi, Shaolan; Meng, Xiangcun; Liu, Zhie

2013-10-01

The double or extended main-sequence turnoffs (MSTOs) in the color-magnitude diagram (CMD) of intermediate-age massive star clusters in the Large Magellanic Cloud are generally interpreted as age spreads of a few hundred Myr. However, such age spreads do not exist in younger clusters (i.e., 40-300 Myr), which challenges this interpretation. The effects of rotation on the MSTOs of star clusters have been studied in previous works, but the results obtained are conflicting. Compared with previous works, we consider the effects of rotation on the main-sequence lifetime of stars. Our calculations show that rotating models have a fainter and redder MSTO with respect to non-rotating counterparts with ages between about 0.8 and 2.2 Gyr, but have a brighter and bluer MSTO when age is larger than 2.4 Gyr. The spread of the MSTO caused by a typical rotation rate is equivalent to the effect of an age spread of about 200 Myr. Rotation could lead to the double or extended MSTOs in the CMD of the star clusters with ages between about 0.8 and 2.2 Gyr. However, the extension is not significant, and it does not even exist in younger clusters. If the efficiency of the mixing were high enough, the effects of the mixing would counteract the effect of the centrifugal support in the late stage of evolution, and the rotationally induced extension would disappear in the old intermediate-age star clusters, but younger clusters would have an extended MSTO. Moreover, the effects of rotation might aid in understanding the formation of some "multiple populations" in globular clusters.

Distributed Adaptive Control: Beyond Single-Instant, Discrete Variables

NASA Technical Reports Server (NTRS)

Wolpert, David H.; Bieniawski, Stefan

2005-01-01

In extensive form noncooperative game theory, at each instant t, each agent i sets its state x, independently of the other agents, by sampling an associated distribution, q(sub i)(x(sub i)). The coupling between the agents arises in the joint evolution of those distributions. Distributed control problems can be cast the same way. In those problems the system designer sets aspects of the joint evolution of the distributions to try to optimize the goal for the overall system. Now information theory tells us what the separate q(sub i) of the agents are most likely to be if the system were to have a particular expected value of the objective function G(x(sub 1),x(sub 2), ...). So one can view the job of the system designer as speeding an iterative process. Each step of that process starts with a specified value of E(G), and the convergence of the q(sub i) to the most likely set of distributions consistent with that value. After this the target value for E(sub q)(G) is lowered, and then the process repeats. Previous work has elaborated many schemes for implementing this process when the underlying variables x(sub i) all have a finite number of possible values and G does not extend to multiple instants in time. That work also is based on a fixed mapping from agents to control devices, so that the the statistical independence of the agents' moves means independence of the device states. This paper also extends that work to relax all of these restrictions. This extends the applicability of that work to include continuous spaces and Reinforcement Learning. This paper also elaborates how some of that earlier work can be viewed as a first-principles justification of evolution-based search algorithms.

Differential Processing for Actively Ignored Pictures and Words

PubMed Central

Ciraolo, Margeaux

2017-01-01

Previous work suggests that, when attended, pictures may be processed more readily than words. The current study extends this research to assess potential differences in processing between these stimulus types when they are actively ignored. In a dual-task paradigm, facilitated recognition for previously ignored words was found provided that they appeared frequently with an attended target. When adapting the same paradigm here, previously unattended pictures were recognized at high rates regardless of how they were paired with items during the primary task, whereas unattended words were later recognized at higher rates only if they had previously been aligned with primary task targets. Implicit learning effects obtained by aligning unattended items with attended task-targets may apply only to conceptually abstract stimulus types, such as words. Pictures, on the other hand, may maintain direct access to semantic information, and are therefore processed more readily than words, even when being actively ignored. PMID:28122022

Differential Processing for Actively Ignored Pictures and Words.

PubMed

Walker, Maegen; Ciraolo, Margeaux; Dewald, Andrew; Sinnett, Scott

2017-01-01

Previous work suggests that, when attended, pictures may be processed more readily than words. The current study extends this research to assess potential differences in processing between these stimulus types when they are actively ignored. In a dual-task paradigm, facilitated recognition for previously ignored words was found provided that they appeared frequently with an attended target. When adapting the same paradigm here, previously unattended pictures were recognized at high rates regardless of how they were paired with items during the primary task, whereas unattended words were later recognized at higher rates only if they had previously been aligned with primary task targets. Implicit learning effects obtained by aligning unattended items with attended task-targets may apply only to conceptually abstract stimulus types, such as words. Pictures, on the other hand, may maintain direct access to semantic information, and are therefore processed more readily than words, even when being actively ignored.

Why are women more likely than men to extend paid work? The impact of work-family life history.

PubMed

Finch, Naomi

2014-03-01

Extending working life beyond the state pension age is a key European Union policy. In the UK, women are more likely to extend paid work than men, indicating that factors other than the state pension age play a role in working longer. Women are less able to build pension income due to their role as carer within the family. It, therefore, follows that gender inequalities over the life course continue into older age to influence need, capacity and desire to undertake paid work after state pension age. This paper explores how work, marital and fertility history impact upon the likelihood of extending employment. It uses the British Household Panel Survey's retrospective data from the first 14 waves to summarise work-family histories, and logistic regression to understand the impact of work and family histories on extending paid work. Findings show that, on the one hand, women are extending paid work for financial reasons to make up for 'opportunity costs' as a result of their caring role within the family, with short breaks due to caring, lengthy marriages, divorcing and remaining single with children all being important. Yet, there is also evidence of 'status maintenance' from working life, with the women most likely to extend paid work, also those with the highest work orientation, prior to state pension age. But lengthy dis-attachment (due to caring) from the labour market makes extending working life more difficult. This has implications for policy strategies to entice women into paid work to make up for low independent financial resources.

CDGPS-Based Relative Navigation for Multiple Spacecraft

NASA Technical Reports Server (NTRS)

Mitchell, Megan Leigh

2004-01-01

This thesis investigates the use of Carrier-phase Differential GPS (CDGPS) in relative navigation filters for formation flying spacecraft. This work analyzes the relationship between the Extended Kalman Filter (EKF) design parameters and the resulting estimation accuracies, and in particular, the effect of the process and measurement noises on the semimajor axis error. This analysis clearly demonstrates that CDGPS-based relative navigation Kalman filters yield good estimation performance without satisfying the strong correlation property that previous work had associated with "good" navigation filters. Several examples are presented to show that the Kalman filter can be forced to create solutions with stronger correlations, but these always result in larger semimajor axis errors. These linear and nonlinear simulations also demonstrated the crucial role of the process noise in determining the semimajor axis knowledge. More sophisticated nonlinear models were included to reduce the propagation error in the estimator, but for long time steps and large separations, the EKF, which only uses a linearized covariance propagation, yielded very poor performance. In contrast, the CDGPS-based Unscented Kalman relative navigation Filter (UKF) handled the dynamic and measurement nonlinearities much better and yielded far superior performance than the EKF. The UKF produced good estimates for scenarios with long baselines and time steps for which the EKF would diverge rapidly. A hardware-in-the-loop testbed that is compatible with the Spirent Simulator at NASA GSFC was developed to provide a very flexible and robust capability for demonstrating CDGPS technologies in closed-loop. This extended previous work to implement the decentralized relative navigation algorithms in real time.

Extending and implementing the Persistent ID pillars

NASA Astrophysics Data System (ADS)

Car, Nicholas; Golodoniuc, Pavel; Klump, Jens

2017-04-01

The recent double decade anniversary of scholarly persistent identifier use has triggered journal special editions such as "20 Years of Persistent Identifiers". For such a publication, it is apt to consider the longevity of some persistent identifier (PID) mechanisms (Digital Object Identifiers) and the partial disappearance of others (Life Sciences IDs). We have previously postulated a set of "PID Pillars" [1] which are design principles aimed at ensuring PIDs can survive technology and social change and thus persist for the long term that we have drawn from our observations of PIDs at work over many years. The principles: describe how to ensure identifiers' system and organisation independence; codify the delivery of essential PID system functions; mandate a separation of PID functions from data delivery mechanisms; and require generation of policies detailing how change is handled. In this presentation, first we extend on our previous work of introducing the pillars by refining their descriptions, giving specific suggestions for each and presenting some work that addresses them. Second, we propose a baseline data model for persistent identifiers that, if used, would assist the separation of PID metadata and PID system functioning. This would allow PID system function specifics to change over time (e.g. resolver services or even resolution protocols) and yet preserve the PIDs themselves. Third, we detail our existing PID system — the PID Service [2] — that partially implements the pillars and describe both its successes and shortcomings. Finally, we describe our planned next-generation system that will aim to use the baseline data model and fully implement the pillars.

Invariant Manifolds, the Spatial Three-Body Problem and Space Mission Design

NASA Technical Reports Server (NTRS)

Gomez, G.; Koon, W. S.; Lo, Martin W.; Marsden, J. E.; Masdemont, J.; Ross, S. D.

2001-01-01

The invariant manifold structures of the collinear libration points for the spatial restricted three-body problem provide the framework for understanding complex dynamical phenomena from a geometric point of view. In particular, the stable and unstable invariant manifold 'tubes' associated to libration point orbits are the phase space structures that provide a conduit for orbits between primary bodies for separate three-body systems. These invariant manifold tubes can be used to construct new spacecraft trajectories, such as 'Petit Grand Tour' of the moons of Jupiter. Previous work focused on the planar circular restricted three-body problem. The current work extends the results to the spatial case.

Spectral measurements of alpha-induced radioluminescence in various gases

NASA Astrophysics Data System (ADS)

Brett, Jaclyn; Koehler, Katrina E.; Bischak, Michael; Famiano, Michael; Jenkins, Jared; Klankowski, Levi; Niraula, Prashantamani; Pancella, Paul; Lakis, Rollin

2017-12-01

Radioluminescent emission in Ar, N2, O2, and dry air at P = 1 atm was observed induced by 5 MeV α particles. The wavelength range with a single detector spanned 250-1100 nm, extending the range well into the UV and IR bands with a single detector. Measured spectral lines for alpha-induced luminescence were corrected for detector transmission and intensities compared to previous work. The exploration of multiple gases over a wide frequency range opens the door to security and remote sensing applications, where different environments are routinely encountered. This work provides spectra that can be used in guiding future filter development focusing on remote alpha detection.

Security in MANETs using reputation-adjusted routing

NASA Astrophysics Data System (ADS)

Ondi, Attila; Hoffman, Katherine; Perez, Carlos; Ford, Richard; Carvalho, Marco; Allen, William

2009-04-01

Mobile Ad-Hoc Networks enable communication in various dynamic environments, including military combat operations. Their open and shared communication medium enables new forms of attack that are not applicable for traditional wired networks. Traditional security mechanisms and defense techniques are not prepared to cope with the new attacks and the lack of central authorities make identity verifications difficult. This work extends our previous work in the Biologically Inspired Tactical Security Infrastructure to provide a reputation-based weighing mechanism for linkstate routing protocols to protect the network from attackers that are corrupting legitimate network traffic. Our results indicate that the approach is successful in routing network traffic around compromised computers.

Stability of smectic phases in hard-rod mixtures

NASA Astrophysics Data System (ADS)

Martínez-Ratón, Yuri; Velasco, Enrique; Mederos, Luis

2005-09-01

Using density-functional theory, we have analyzed the phase behavior of binary mixtures of hard rods of different lengths and diameters. Previous studies have shown a strong tendency of smectic phases of these mixtures to segregate and, in some circumstances, to form microsegregated phases. Our focus in the present work is on the formation of columnar phases which some studies, under some approximations, have shown to become thermodynamically stable prior to crystallization. Specifically we focus on the relative stability between smectic and columnar phases, a question not fully addressed in previous work. Our analysis is based on two complementary perspectives: on the one hand, an extended Onsager theory, which includes the full orientational degrees of freedom but with spatial and orientational correlations being treated in an approximate manner; on the other hand, we formulate a Zwanzig approximation of fundamental-measure theory on hard parallelepipeds, whereby orientations are restricted to be only along three mutually orthogonal axes, but correlations are faithfully represented. In the latter case novel, complete phase diagrams containing regions of stability of liquid-crystalline phases are calculated. Our findings indicate that the restricted-orientation approximation enhances the stability of columnar phases so as to preempt smectic order completely while, in the framework of the extended Onsager model, with full orientational degrees of freedom taken into account, columnar phases may preempt a large region of smectic stability in some mixtures, but some smectic order still persists.

More on heavy tetraquarks in lattice QCD at almost physical pion mass

NASA Astrophysics Data System (ADS)

Francis, Anthony; Hudspith, Renwick J.; Lewis, Randy; Maltman, Kim

2018-03-01

We report on our progress in studying exotic, heavy tetraquark states, qq' Q̅Q̅'. Using publicly available dynamical nf = 2 + 1 Wilson-Clover gauge configurations, generated by the PACS-CS collaboration, with pion masses ≃ 164, 299 and 415 MeV, we extend our previous analysis to heavy quark components containing heavier than physical bottom quarks Q̅Q̅' = b̅'b̅' or Q̅Q̅' = b̅b̅', charm and bottom quarks c̅b̅ and also only charm quarks c̅ c̅. Throughout we employ NRQCD and relativistic heavy quarks for the heavier than bottom, bottom and charm quarks. Using our previously established diquark-antidiquark and meson-meson operator basis we comment in particular on the dependence of the binding energy on the mass of the heavy quark component Q̅Q̅, with heavy quarks ranging from mQ = 0:85… 6.3 · mb. In the heavy flavor non-degenerate case, Q̅Q̅', and especially for the tetraquark channel udc̅d̅, we extend our work to utilize a 3 × 3 GEVP to study the ground and threshold states thereby enabling a clear identification of possible binding. Finally, we present initial work on the Q̅Q̅' = c̅c̅ system where a much larger operator basis is available in comparison to flavor combinations with NRQCD quarks.

Simulations of Tokamak Edge Turbulence Including Self-Consistent Zonal Flows

NASA Astrophysics Data System (ADS)

Cohen, Bruce; Umansky, Maxim

2013-10-01

Progress on simulations of electromagnetic drift-resistive ballooning turbulence in the tokamak edge is summarized in this mini-conference talk. A more detailed report on this work is presented in a poster at this conference. This work extends our previous work to include self-consistent zonal flows and their effects. The previous work addressed the simulation of L-mode tokamak edge turbulence using the turbulence code BOUT. The calculations used realistic single-null geometry and plasma parameters of the DIII-D tokamak and produced fluctuation amplitudes, fluctuation spectra, and particle and thermal fluxes that compare favorably to experimental data. In the effect of sheared ExB poloidal rotation is included with an imposed static radial electric field fitted to experimental data. In the new work here we include the radial electric field self-consistently driven by the microturbulence, which contributes to the sheared ExB poloidal rotation (zonal flow generation). We present simulations with/without zonal flows for both cylindrical geometry, as in the UCLA Large Plasma Device, and for the DIII-D tokamak L-mode cases in to quantify the influence of self-consistent zonal flows on the microturbulence and the concomitant transport. This work was performed under the auspices of the US Department of Energy under contract DE-AC52-07NA27344 at the Lawrence Livermore National Laboratory.

Examining the Gender Gap in Introductory Physics

NASA Astrophysics Data System (ADS)

Kost, Lauren; Pollock, Steven; Finkelstein, Noah

2009-05-01

Our previous research[1] showed that despite the use of interactive engagement techniques in the introductory physics course, the gap in performance between males and females on a mechanics conceptual learning survey persisted from pre- to post-test, at our institution. Such findings were counter to previously published work[2]. Follow-up studies[3] identified correlations between student performance on the conceptual learning survey and students' prior physics and math knowledge and their incoming attitudes and beliefs about physics and learning physics. The results indicate that the gender gap at our institution is predominantly associated with differences in males' and females' previous physics and math knowledge, and attitudes and beliefs. Our current work extends these results in two ways: 1) we look at the gender gap in the second semester of the introductory sequence and find results similar to those in the first semester course and 2) we identify ways in which males and females differentially experience several aspects of the introductory course. [1] Pollock, et al, Phys Rev: ST: PER 3, 010107. [2] Lorenzo, et al, Am J Phys 74, 118. [3] Kost, et al, PERC Proceedings 2008.

Nurses' extended work hours: Patient, nurse and organizational outcomes.

PubMed

Kunaviktikul, W; Wichaikhum, O; Nantsupawat, A; Nantsupawat, R; Chontawan, R; Klunklin, A; Roongruangsri, S; Nantachaipan, P; Supamanee, T; Chitpakdee, B; Akkadechanunt, T; Sirakamon, S

2015-09-01

Nursing shortages have been associated with increased nurse workloads that may result in work errors, thus impacting patient, nurse and organizational outcomes. To examine for the first time in Thailand nurses' extended work hours (working more than 40 h per week) and its relationship to patient, nurse and organizational outcomes. Using multistage sampling, 1524 registered nurses working in 90 hospitals across Thailand completed demographic forms: the Nurses' Extended Work Hours Form; the Patient, Nurse, Organizational Outcomes Form; the Organizational Productivity Questionnaire and the Maslach Burnout Inventory. The data were analysed using descriptive statistics, Spearman's rank correlation and logistic regression. The average extended work hour of respondents was 18.82 h per week. About 80% worked two consecutive shifts. The extended work hours had a positive correlation with patient outcomes, such as patient identification errors, pressure ulcers, communication errors and patient complaints and with nurse outcomes of emotional exhaustion and depersonalization. Furthermore, we found a negative correlation between extended work hours and job satisfaction as a whole, intent to stay and organizational productivity. Nurses who had extended work hours of >16 h per week were significantly more likely to perceive all four adverse patient outcomes than participants working an extended ≤8 h per week. Patient outcomes were measured by respondents' self-reports. This may not always reflect the real occurrence of adverse events. Associations between extended work hours and outcomes for patients, nurses and the organization were found. The findings demonstrate that working two shifts (16 h) more than the regular work hours lead to negative outcomes for patients, nurses and the organization. Our findings add to increasing international evidence that nurses' poor working conditions result in negative outcomes for professionals, patients and health systems. Policymakers need to be aware of the issues regarding nurses' extended work hours, which has been found to contribute to burnout. Urgently, nurse and health administrators need to develop and implement appropriate nursing overtime policies and strategies to help reduce this phenomenon, including measures to overcome the nursing shortage. © 2015 International Council of Nurses.

Exploring factors that influence work analysis data: A meta-analysis of design choices, purposes, and organizational context.

PubMed

DuVernet, Amy M; Dierdorff, Erich C; Wilson, Mark A

2015-09-01

Work analysis is fundamental to designing effective human resource systems. The current investigation extends previous research by identifying the differential effects of common design decisions, purposes, and organizational contexts on the data generated by work analyses. The effects of 19 distinct factors that span choices of descriptor, collection method, rating scale, and data source, as well as project purpose and organizational features, are explored. Meta-analytic results cumulated from 205 articles indicate that many of these variables hold significant consequences for work analysis data. Factors pertaining to descriptor choice, collection method, rating scale, and the purpose for conducting the work analysis each showed strong associations with work analysis data. The source of the work analysis information and organizational context in which it was conducted displayed fewer relationships. Findings can be used to inform choices work analysts make about methodology and postcollection evaluations of work analysis information. (c) 2015 APA, all rights reserved).

Extensive numerical study of a D-brane, anti-D-brane system in AdS 5 /CFT 4

NASA Astrophysics Data System (ADS)

Hegedűs, Árpád

2015-04-01

In this paper the hybrid-NLIE approach of [38] is extended to the ground state of a D-brane anti-D-brane system in AdS/CFT. The hybrid-NLIE equations presented in the paper are finite component alternatives of the previously proposed TBA equations and they admit an appropriate framework for the numerical investigation of the ground state of the problem. Straightforward numerical iterative methods fail to converge, thus new numerical methods are worked out to solve the equations. Our numerical data confirm the previous TBA data. In view of the numerical results the mysterious L = 1 case is also commented in the paper.

Employment Implications of Informal Cancer Caregiving

PubMed Central

de Moor, Janet S.; Dowling, Emily C.; Ekwueme, Donatus U.; Guy, Gery P.; Rodriguez, Juan; Virgo, Katherine S.; Han, Xuesong; Kent, Erin E.; Li, Chunyu; Litzelman, Kristen; McNeel, Timothy S.; Liu, Benmei; Yabroff, K. Robin

2016-01-01

Purpose Previous research describing how informal cancer caregiving impacts employment has been conducted in small samples or a single disease site. This paper provides population-based estimates of the effect of cancer caregiving on employment and characterizes the employment changes made by caregivers. Methods The sample comprised cancer survivors with a friend or family caregiver, participating in either the Medical Expenditure Panel Survey Experiences with Cancer Survivorship Survey (ECSS) (n=458) or the LIVESTRONG 2012 Survey for People Affected by Cancer (SPAC) (n=4,706). Descriptive statistics characterized the sample of survivors and their caregivers’ employment changes. Multivariable logistic regression identified predictors of caregivers’ extended employment changes, comprising time off and changes to hours, duties or employment status. Results Among survivors with an informal caregiver, 25% from the ECSS and 29% from the SPAC reported their caregivers made extended employment changes. Approximately 8% of survivors had caregivers who took time off from work lasting ≥ 2 months. Caregivers who made extended employment changes were more likely to care for survivors treated with chemotherapy or transplant; closer to diagnosis or end of treatment; who experienced functional limitations; and made work changes due to cancer themselves compared to caregivers who did not make extended employment changes. Conclusions Many informal cancer caregivers make employment changes to provide care during survivors’ treatment and recovery. Implications for cancer survivors This study describes cancer caregiving in a prevalent sample of cancer survivors, thereby reflecting the experiences of individuals with many different cancer types and places in the cancer treatment trajectory. PMID:27423439

Employment implications of informal cancer caregiving.

PubMed

de Moor, Janet S; Dowling, Emily C; Ekwueme, Donatus U; Guy, Gery P; Rodriguez, Juan; Virgo, Katherine S; Han, Xuesong; Kent, Erin E; Li, Chunyu; Litzelman, Kristen; McNeel, Timothy S; Liu, Benmei; Yabroff, K Robin

2017-02-01

Previous research describing how informal cancer caregiving impacts employment has been conducted in small samples or a single disease site. This paper provides population-based estimates of the effect of informal cancer caregiving on employment and characterizes employment changes made by caregivers. The samples included cancer survivors with a friend or family caregiver, participating in either the Medical Expenditure Panel Survey Experiences with Cancer Survivorship Survey (ECSS) (n = 458) or the LIVESTRONG 2012 Survey for People Affected by Cancer (SPAC) (n = 4706). Descriptive statistics characterized the sample of survivors and their caregivers' employment changes. Multivariable logistic regression identified predictors of caregivers' extended employment changes, comprising time off and changes to hours, duties, or employment status. Among survivors with an informal caregiver, 25 % from the ECSS and 29 % from the SPAC reported that their caregivers made extended employment changes. Approximately 8 % of survivors had caregivers who took time off from work lasting ≥2 months. Caregivers who made extended employment changes were more likely to care for survivors: treated with chemotherapy or transplant; closer to diagnosis or end of treatment; who experienced functional limitations; and made work changes due to cancer themselves compared to caregivers who did not make extended employment changes. Many informal cancer caregivers make employment changes to provide care during survivors' treatment and recovery. This study describes cancer caregiving in a prevalent sample of cancer survivors, thereby reflecting the experiences of individuals with many different cancer types and places in the cancer treatment trajectory.

Combustion of Interacting Droplet Arrays in a Microgravity Environment

NASA Technical Reports Server (NTRS)

Dietrich, D. L.; Struk, P. M.; Ikegami, M.; Nagaishi, H.; Honma, S.; Ikeda, K.

2001-01-01

Investigations into droplet interactions date back to Rex et al. Annamalai and Ryan and Annamalai published extensive reviews of droplet array and cloud combustion studies. In the majority of the reviewed studies, the authors examined the change in the burning rate constant, k, (relative to that of the single droplet) that results from interactions. More recently, Niioka and co-workers have examined ignition and flame propagation along arrays of interacting droplets with the goal of relating these phenomena in this simplified geometry to the more practical spray configuration. Our work has focussed on droplet interactions under conditions where flame extinction occurs at a finite droplet diameter. In our previous work, we reported that in normal gravity, reduced pressure conditions, droplet interactions improved flame stability and extended flammability limits (by inference). In our recent work, we examine droplet interactions under conditions where the flame extinguishes at a finite droplet diameter in microgravity. The microgravity experiments were in the NASA GRC 2.2 and 5.2 second drop towers, and the JAMIC (Japan Microgravity Center) 10 second drop tower. We also present progress on a numerical model of single droplet combustion that is in the process of being extended to model a binary droplet array.

The role of collaborative ontology development in the knowledge negotiation process

NASA Astrophysics Data System (ADS)

Rivera, Norma

Interdisciplinary research (IDR) collaboration can be defined as the process of integrating experts' knowledge, perspectives, and resources to advance scientific discovery. The flourishing of more complex research problems, together with the growth of scientific and technical knowledge has resulted in the need for researchers from diverse fields to provide different expertise and points of view to tackle these problems. These collaborations, however, introduce a new set of "culture" barriers as participating experts are trained to communicate in discipline-specific languages, theories, and research practices. We propose that building a common knowledge base for research using ontology development techniques can provide a starting point for interdisciplinary knowledge exchange, negotiation, and integration. The goal of this work is to extend ontology development techniques to support the knowledge negotiation process in IDR groups. Towards this goal, this work presents a methodology that extends previous work in collaborative ontology development and integrates learning strategies and tools to enhance interdisciplinary research practices. We evaluate the effectiveness of applying such methodology in three different scenarios that cover educational and research settings. The results of this evaluation confirm that integrating learning strategies can, in fact, be advantageous to overall collaborative practices in IDR groups.

A Non-parametric Approach to Constrain the Transfer Function in Reverberation Mapping

NASA Astrophysics Data System (ADS)

Li, Yan-Rong; Wang, Jian-Min; Bai, Jin-Ming

2016-11-01

Broad emission lines of active galactic nuclei stem from a spatially extended region (broad-line region, BLR) that is composed of discrete clouds and photoionized by the central ionizing continuum. The temporal behaviors of these emission lines are blurred echoes of continuum variations (I.e., reverberation mapping, RM) and directly reflect the structures and kinematic information of BLRs through the so-called transfer function (also known as the velocity-delay map). Based on the previous works of Rybicki and Press and Zu et al., we develop an extended, non-parametric approach to determine the transfer function for RM data, in which the transfer function is expressed as a sum of a family of relatively displaced Gaussian response functions. Therefore, arbitrary shapes of transfer functions associated with complicated BLR geometry can be seamlessly included, enabling us to relax the presumption of a specified transfer function frequently adopted in previous studies and to let it be determined by observation data. We formulate our approach in a previously well-established framework that incorporates the statistical modeling of continuum variations as a damped random walk process and takes into account long-term secular variations which are irrelevant to RM signals. The application to RM data shows the fidelity of our approach.

Factor structure of a standards-based inventory of competencies in social work with groups.

PubMed

Macgowan, Mark J; Dillon, Frank R; Spadola, Christine E

2018-01-01

This study extends previous findings on a measure of competencies based on Standards for Social Work Practice with Groups. The Inventory of Competencies in Social Work with Groups (ICSWG) measures confidence in performing the Standards. This study examines the latent structure of the Inventory, while illuminating the underlying structure of the Standards. A multinational sample of 586 persons completed the ICSWG. Exploratory factor analysis (EFA), reliability estimates, standard error of measurement estimates, and a range of validity tests were conducted. The EFA yielded a six-factor solution consisting of core values, mutuality/connectivity, collaboration, and three phases of group development (planning, beginnings/middles, endings). The alphas were .98 for the scale and ranged from .85 to .95 for the subscales. Correlations between the subscales and validators supported evidence of construct validity. The findings suggest key group work domains that should be taught and practiced in social work with groups.

Analysis of Ground Water Flow and Deformation in the Vicinity of DUSEL Homestake

NASA Astrophysics Data System (ADS)

Murdoch, L. C.; Ebenhack, J.; Germanovich, L. N.; Wang, H. F.; Boutt, D. F.; Onstott, T. C.; Kieft, T.; Moser, D. P.; Elsworth, D.

2010-12-01

The Deep Underground Science and Engineering Laboratory (DUSEL) is an underground facility planned for the workings of the former Homestake gold mine in the northern Black Hills, South Dakota. The mine workings cover several km2 in plan and extend to a depth 2.4 km. The area is underlain by Proterozoic metamorphic rocks that were deformed into regional-scale folds whose axes plunge approximately 40o to the SSE. A conceptual model and preliminary numerical analysis of the hydrogeology of the area indicates that permeability depends on effective stress, with values ranging from 0.1 mD at a depth of 2 km to 100 mD at depths of 100m. A deep ground water flow system is contained within a surface-truncated ellipsoid roughly 8 km by 4 km in plan view and 5.5 km deep with its short-axis aligned to the strike of the workings. The deep flow system consists of a zone of relatively rapid flow from the ground surface to the workings overlying the southern part of the mine, and a much larger ellipsoidal zone extending up to several km from the workings where water has been removed from storage. Numerical analyses of the ground water flow and poroelastic deformation in the vicinity of Homestake DUSEL have been refined by sharpening the 3-D resolution of important features. Mine workings have been resolved into three to four major regions where relatively large densities of rock were removed. These mined regions are shaped roughly like plunging ellipsoids with minor axes of several hundred m and major axes up to more than 2 km. They are treated in the simulations as highly permeable regions with an average elastic modulus significantly less than the intact rock; e.g. like soft, permeable inclusions. Recent field investigations and evaluation of the mine database indicate the presence of a relatively large fault that strikes approximately N20W, roughly parallel to the mined out regions. The Homestake fault dips 60NE, cutting the top of one mined region and extending beneath and adjacent to another mined region. It extends at least 1.5 km along strike and dip, with a center roughly 1.5 km deep along the western side of the mine. The model includes large-scale folds, and in particular it includes the geometry of the Yates member at the core of the Lead Anticlinorium. Topography and the stream drainage network are also included. The findings generally confirm previous results of Murdoch et al. [Eos Trans. AGU, 90(52), Fall Meet. Suppl., Abstract H23E-1009], but the finer resolution from the new analyses provides improved detail on the distribution of hydraulic head and stress state in the vicinity of the workings. Including the poroelastic effect shows that dewatering of the mined workings may cause larger deformations than were previously expected, and it also indicates that dewatering should affect the distribution of stresses on the Homestake fault.

Image reconstruction in cone-beam CT with a spherical detector using the BPF algorithm

NASA Astrophysics Data System (ADS)

Zuo, Nianming; Zou, Yu; Jiang, Tianzi; Pan, Xiaochuan

2006-03-01

Both flat-panel detectors and cylindrical detectors have been used in CT systems for data acquisition. The cylindrical detector generally offers a sampling of a transverse image plane more uniformly than does a flat-panel detector. However, in the longitudinal dimension, the cylindrical and flat-panel detectors offer similar sampling of the image space. In this work, we investigate a detector of spherical shape, which can yield uniform sampling of the 3D image space because the solid angle subtended by each individual detector bin remains unchanged. We have extended the backprojection-filtration (BPF) algorithm, which we have developed previously for cone-beam CT, to reconstruct images in cone-beam CT with a spherical detector. We also conduct computer-simulation studies to validate the extended BPF algorithm. Quantitative results in these numerical studies indicate that accurate images can be obtained from data acquired with a spherical detector by use of our extended BPF cone-beam algorithms.

The use of genetic programming to develop a predictor of swash excursion on sandy beaches

NASA Astrophysics Data System (ADS)

Passarella, Marinella; Goldstein, Evan B.; De Muro, Sandro; Coco, Giovanni

2018-02-01

We use genetic programming (GP), a type of machine learning (ML) approach, to predict the total and infragravity swash excursion using previously published data sets that have been used extensively in swash prediction studies. Three previously published works with a range of new conditions are added to this data set to extend the range of measured swash conditions. Using this newly compiled data set we demonstrate that a ML approach can reduce the prediction errors compared to well-established parameterizations and therefore it may improve coastal hazards assessment (e.g. coastal inundation). Predictors obtained using GP can also be physically sound and replicate the functionality and dependencies of previous published formulas. Overall, we show that ML techniques are capable of both improving predictability (compared to classical regression approaches) and providing physical insight into coastal processes.

Applying Cost-Sensitive Extreme Learning Machine and Dissimilarity Integration to Gene Expression Data Classification.

PubMed

Liu, Yanqiu; Lu, Huijuan; Yan, Ke; Xia, Haixia; An, Chunlin

2016-01-01

Embedding cost-sensitive factors into the classifiers increases the classification stability and reduces the classification costs for classifying high-scale, redundant, and imbalanced datasets, such as the gene expression data. In this study, we extend our previous work, that is, Dissimilar ELM (D-ELM), by introducing misclassification costs into the classifier. We name the proposed algorithm as the cost-sensitive D-ELM (CS-D-ELM). Furthermore, we embed rejection cost into the CS-D-ELM to increase the classification stability of the proposed algorithm. Experimental results show that the rejection cost embedded CS-D-ELM algorithm effectively reduces the average and overall cost of the classification process, while the classification accuracy still remains competitive. The proposed method can be extended to classification problems of other redundant and imbalanced data.

Cheating prevention in visual cryptography.

PubMed

Hu, Chih-Ming; Tzeng, Wen-Guey

2007-01-01

Visual cryptography (VC) is a method of encrypting a secret image into shares such that stacking a sufficient number of shares reveals the secret image. Shares are usually presented in transparencies. Each participant holds a transparency. Most of the previous research work on VC focuses on improving two parameters: pixel expansion and contrast. In this paper, we studied the cheating problem in VC and extended VC. We considered the attacks of malicious adversaries who may deviate from the scheme in any way. We presented three cheating methods and applied them on attacking existent VC or extended VC schemes. We improved one cheat-preventing scheme. We proposed a generic method that converts a VCS to another VCS that has the property of cheating prevention. The overhead of the conversion is near optimal in both contrast degression and pixel expansion.

Extended working shifts: are they applicable to the Southeastern United States?

Treesearch

Dana Mitchell; Tom Gallagher

2006-01-01

Logging operations in Scandinavia, Canada and the Lake States of the United States have used non-traditional (extended) working hours to increase their production for many years. However, extended shifts are uncommon in the southeastern United States. A major limitation in implementing extended working hours in the southeastern states is that logging business owners...

New electron-energy transfer rates for vibrational excitation of O2

NASA Astrophysics Data System (ADS)

Jones, D. B.; Campbell, L.; Bottema, M. J.; Brunger, M. J.

2003-09-01

We report on our computation of electron-energy transfer rates for vibrational excitation of O2. This work was necessitated by inadequacies in the electron-impact cross section databases employed in previous studies and, in one case, an inaccurate approximate formulation to the rate equation. Both these inadequacies led to incorrect energy transfer rates being published in the literature. We also demonstrate the importance of using cross sections that encompass an energy range that is extended enough to appropriately describe the environment under investigation.

Multiplicity-dependent and nonbinomial efficiency corrections for particle number cumulants

NASA Astrophysics Data System (ADS)

Bzdak, Adam; Holzmann, Romain; Koch, Volker

2016-12-01

In this article we extend previous work on efficiency corrections for cumulant measurements [Bzdak and Koch, Phys. Rev. C 86, 044904 (2012), 10.1103/PhysRevC.86.044904; Phys. Rev. C 91, 027901 (2015), 10.1103/PhysRevC.91.027901]. We will discuss the limitations of the methods presented in these papers. Specifically we will consider multiplicity dependent efficiencies as well as nonbinomial efficiency distributions. We will discuss the most simple and straightforward methods to implement those corrections.

Phase retrieval from local measurements in two dimensions

NASA Astrophysics Data System (ADS)

Iwen, Mark; Preskitt, Brian; Saab, Rayan; Viswanathan, Aditya

2017-08-01

The phase retrieval problem has appeared in a multitude of applications for decades. While ad hoc solutions have existed since the early 1970s, recent developments have provided algorithms that offer promising theoretical guarantees under increasingly realistic assumptions. Motivated by ptychographic imaging, we generalize a recent result on phase retrieval of a one dimensional objective vector x ∈ ℂd to recover a two dimensional sample Q ∈ ℂd x d from phaseless measurements, using a tensor product formulation to extend the previous work.

Scalar discrete nonlinear multipoint boundary value problems

NASA Astrophysics Data System (ADS)

Rodriguez, Jesus; Taylor, Padraic

2007-06-01

In this paper we provide sufficient conditions for the existence of solutions to scalar discrete nonlinear multipoint boundary value problems. By allowing more general boundary conditions and by imposing less restrictions on the nonlinearities, we obtain results that extend previous work in the area of discrete boundary value problems [Debra L. Etheridge, Jesus Rodriguez, Periodic solutions of nonlinear discrete-time systems, Appl. Anal. 62 (1996) 119-137; Debra L. Etheridge, Jesus Rodriguez, Scalar discrete nonlinear two-point boundary value problems, J. Difference Equ. Appl. 4 (1998) 127-144].

On the relevance of Gibson's affordance concept for geographical information science (GISc).

PubMed

Jonietz, David; Timpf, Sabine

2015-09-01

J. J. Gibson's concept of affordances has provided a theoretical basis for various studies in geographical information science (GISc). This paper sets out to explain its popularity from a GISc perspective. Based on a short review of previous work, it will be argued that its main contributions to GISc are twofold, including an action-centered view of spatial entities and the notion of agent-environment mutuality. Using the practical example of pedestrian behavior simulation, new potentials for using and extending affordances are discussed.

Far ultraviolet spectrophotometry of BD +28 4211

NASA Technical Reports Server (NTRS)

Cook, Timothy A.; Cash, Webster; Green, James C.

1991-01-01

The results are reported of a November 1989 rocket flight which recorded a flux-calibrated spectrum of BD +28 4211 from 912 to 1150 A with 1A resolution. BD +28 4211, an SdO-type star, is commonly used as an ultraviolet calibration source in the IUE wavelength band. The present work extends the useful range of this standard shortward of Lyman-alpha. Since previous experiments show marked disparity, this study can be useful in determining a standard in the 912 to 1216 A band.

Cognitive Modeling for Agent-Based Simulation of Child Maltreatment

NASA Astrophysics Data System (ADS)

Hu, Xiaolin; Puddy, Richard

This paper extends previous work to develop cognitive modeling for agent-based simulation of child maltreatment (CM). The developed model is inspired from parental efficacy, parenting stress, and the theory of planned behavior. It provides an explanatory, process-oriented model of CM and incorporates causality relationship and feedback loops from different factors in the social ecology in order for simulating the dynamics of CM. We describe the model and present simulation results to demonstrate the features of this model.

An extended Reed Solomon decoder design

NASA Technical Reports Server (NTRS)

Chen, J.; Owsley, P.; Purviance, J.

1991-01-01

It has previously been shown that the Reed-Solomon (RS) codes can correct errors beyond the Singleton and Rieger Bounds with an arbitrarily small probability of a miscorrect. That is, an (n,k) RS code can correct more than (n-k)/2 errors. An implementation of such an RS decoder is presented in this paper. An existing RS decoder, the AHA4010, is utilized in this work. This decoder is especially useful for errors which are patterned with a long burst plus some random errors.

More Toda-like (0,2) mirrors

NASA Astrophysics Data System (ADS)

Chen, Zhuo; Guo, Jirui; Sharpe, Eric; Wu, Ruoxu

2017-08-01

In this paper, we extend our previous work to construct (0 , 2) Toda-like mirrors to A/2-twisted theories on more general spaces, as part of a program of understanding (0,2) mirror symmetry. Specifically, we propose (0 , 2) mirrors to GLSMs on toric del Pezzo surfaces and Hirzebruch surfaces with deformations of the tangent bundle. We check the results by comparing correlation functions, global symmetries, as well as geometric blowdowns with the corresponding (0 , 2) Toda-like mirrors. We also briefly discuss Grassmannian manifolds.

Multiplicity-dependent and nonbinomial efficiency corrections for particle number cumulants

DOE PAGES

Bzdak, Adam; Holzmann, Romain; Koch, Volker

2016-12-19

Here, we extend previous work on efficiency corrections for cumulant measurements [Bzdak and Koch, Phys. Rev. C 86, 044904 (2012)PRVCAN0556-281310.1103/PhysRevC.86.044904; Phys. Rev. C 91, 027901 (2015)PRVCAN0556-281310.1103/PhysRevC.91.027901]. We will then discuss the limitations of the methods presented in these papers. Specifically we will consider multiplicity dependent efficiencies as well as nonbinomial efficiency distributions. We will discuss the most simple and straightforward methods to implement those corrections.

Dual PECCS: a cognitive system for conceptual representation and categorization

NASA Astrophysics Data System (ADS)

Lieto, Antonio; Radicioni, Daniele P.; Rho, Valentina

2017-03-01

In this article we present an advanced version of Dual-PECCS, a cognitively-inspired knowledge representation and reasoning system aimed at extending the capabilities of artificial systems in conceptual categorization tasks. It combines different sorts of common-sense categorization (prototypical and exemplars-based categorization) with standard monotonic categorization procedures. These different types of inferential procedures are reconciled according to the tenets coming from the dual process theory of reasoning. On the other hand, from a representational perspective, the system relies on the hypothesis of conceptual structures represented as heterogeneous proxytypes. Dual-PECCS has been experimentally assessed in a task of conceptual categorization where a target concept illustrated by a simple common-sense linguistic description had to be identified by resorting to a mix of categorization strategies, and its output has been compared to human responses. The obtained results suggest that our approach can be beneficial to improve the representational and reasoning conceptual capabilities of standard cognitive artificial systems, and - in addition - that it may be plausibly applied to different general computational models of cognition. The current version of the system, in fact, extends our previous work, in that Dual- PECCS is now integrated and tested into two cognitive architectures, ACT-R and CLARION, implementing different assumptions on the underlying invariant structures governing human cognition. Such integration allowed us to extend our previous evaluation.

Earthquake fracture energy inferred from kinematic rupture models on extended faults

USGS Publications Warehouse

Tinti, E.; Spudich, P.; Cocco, M.

2005-01-01

We estimate fracture energy on extended faults for several recent earthquakes by retrieving dynamic traction evolution at each point on the fault plane from slip history imaged by inverting ground motion waveforms. We define the breakdown work (Wb) as the excess of work over some minimum traction level achieved during slip. Wb is equivalent to "seismological" fracture energy (G) in previous investigations. Our numerical approach uses slip velocity as a boundary condition on the fault. We employ a three-dimensional finite difference algorithm to compute the dynamic traction evolution in the time domain during the earthquake rupture. We estimate Wb by calculating the scalar product between dynamic traction and slip velocity vectors. This approach does not require specifying a constitutive law and assuming dynamic traction to be collinear with slip velocity. If these vectors are not collinear, the inferred breakdown work depends on the initial traction level. We show that breakdown work depends on the square of slip. The spatial distribution of breakdown work in a single earthquake is strongly correlated with the slip distribution. Breakdown work density and its integral over the fault, breakdown energy, scale with seismic moment according to a power law (with exponent 0.59 and 1.18, respectively). Our estimates of breakdown work range between 4 ?? 105 and 2 ?? 107 J/m2 for earthquakes having moment magnitudes between 5.6 and 7.2. We also compare our inferred values with geologic surface energies. This comparison might suggest that breakdown work for large earthquakes goes primarily into heat production. Copyright 2005 by the American Geophysical Union.

Dicer cleaves 5'-extended microRNA precursors originating from RNA polymerase II transcription start sites.

PubMed

Sheng, Peike; Fields, Christopher; Aadland, Kelsey; Wei, Tianqi; Kolaczkowski, Oralia; Gu, Tongjun; Kolaczkowski, Bryan; Xie, Mingyi

2018-05-09

MicroRNAs (miRNAs) are approximately 22 nucleotide (nt) long and play important roles in post-transcriptional regulation in both plants and animals. In animals, precursor (pre-) miRNAs are ∼70 nt hairpins produced by Drosha cleavage of long primary (pri-) miRNAs in the nucleus. Exportin-5 (XPO5) transports pre-miRNAs into the cytoplasm for Dicer processing. Alternatively, pre-miRNAs containing a 5' 7-methylguanine (m7G-) cap can be generated independently of Drosha and XPO5. Here we identify a class of m7G-capped pre-miRNAs with 5' extensions up to 39 nt long. The 5'-extended pre-miRNAs are transported by Exportin-1 (XPO1). Unexpectedly, a long 5' extension does not block Dicer processing. Rather, Dicer directly cleaves 5'-extended pre-miRNAs by recognizing its 3' end to produce mature 3p miRNA and extended 5p miRNA both in vivo and in vitro. The recognition of 5'-extended pre-miRNAs by the Dicer Platform-PAZ-Connector (PPC) domain can be traced back to ancestral animal Dicers, suggesting that this previously unrecognized Dicer reaction mode is evolutionarily conserved. Our work reveals additional genetic sources for small regulatory RNAs and substantiates Dicer's essential role in RNAi-based gene regulation.

Limit cycles in piecewise-affine gene network models with multiple interaction loops

NASA Astrophysics Data System (ADS)

Farcot, Etienne; Gouzé, Jean-Luc

2010-01-01

In this article, we consider piecewise affine differential equations modelling gene networks. We work with arbitrary decay rates, and under a local hypothesis expressed as an alignment condition of successive focal points. The interaction graph of the system may be rather complex (multiple intricate loops of any sign, multiple thresholds, etc.). Our main result is an alternative theorem showing that if a sequence of region is periodically visited by trajectories, then under our hypotheses, there exists either a unique stable periodic solution, or the origin attracts all trajectories in this sequence of regions. This result extends greatly our previous work on a single negative feedback loop. We give several examples and simulations illustrating different cases.

Spectral Measurements of Alpha-induced Radioluminescence in Various Gases

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

Brett, Jaclyn; Koehler, Katrina Elizabeth; Bischak, Michael

Radioluminescent emission in Ar, N 2, O 2, and dry air at P=1 atm was observed induced by 5 MeV α particles. The wavelength range with a single detector spanned 250–1100 nm, extending the range well into the UV and IR bands with a single detector. Measured spectral lines for alpha-induced luminescence were corrected for detector transmission and intensities compared to previous work. The exploration of multiple gases over a wide frequency range opens the door to security and remote sensing applications, where different environments are routinely encountered. Finally, this work provides spectra that can be used in guiding futuremore » filter development focusing on remote alpha detection.« less

Spectral Measurements of Alpha-induced Radioluminescence in Various Gases

DOE PAGES

Brett, Jaclyn; Koehler, Katrina Elizabeth; Bischak, Michael; ...

2017-09-06

Radioluminescent emission in Ar, N 2, O 2, and dry air at P=1 atm was observed induced by 5 MeV α particles. The wavelength range with a single detector spanned 250–1100 nm, extending the range well into the UV and IR bands with a single detector. Measured spectral lines for alpha-induced luminescence were corrected for detector transmission and intensities compared to previous work. The exploration of multiple gases over a wide frequency range opens the door to security and remote sensing applications, where different environments are routinely encountered. Finally, this work provides spectra that can be used in guiding futuremore » filter development focusing on remote alpha detection.« less

Decentralised control of continuous Petri nets

NASA Astrophysics Data System (ADS)

Wang, Liewei; Wang, Xu

2017-05-01

This paper focuses on decentralised control of systems modelled by continuous Petri nets, in which a target marking control problem is discussed. In some previous works, an efficient ON/OFF strategy-based minimum-time controller was developed. Nevertheless, the convergence is only proved for subclasses like Choice-Free nets. For a general net, the pre-conditions of applying the ON/OFF strategy are not given; therefore, the application scope of the method is unclear. In this work, we provide two sufficient conditions of applying the ON/OFF strategy-based controller to general nets. Furthermore, an extended algorithm for general nets is proposed, in which control laws are computed based on some limited information, without knowing the detailed structure of subsystems.

HIGH EXPLOSIVE CRATER STUDIES: DESERT ALLUVIUM

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

Murphey, B.F.

1961-05-01

Crater dimensions were determined for 23 explosions of 256-pound spherical TNT charges buried in desert alluvium. As opposed to previous work covering depths of burst as great as 6 feet, the work presented in this report extends knowledge of apparent crater radius and depth to depths of burst as great as 30 feet. Optimum depth of burst for apparent crater radius was near 10 feet and for apparent crater depth near 8 feet. Surface motion photography illustrated a very great slowing down of the surface motion between depths of burst of 9.5 and 15.9 feet. Crater contours, profiles, snd overheadmore » photographs are presented as illustrations. (auth)« less

International Space Station Environmental Control and Life Support System Previous Year Status for 2013 - 2014

NASA Technical Reports Server (NTRS)

Williams, David E.; Gentry, Gregory J.

2015-01-01

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year and the impacts of the international partners' activities on them, covering the period of time between March 2013 and February 2014. The ISS continued permanent crew operations including the continuation of six crew members being on ISS. Work continues on the commercial crew vehicles, and work to try and extend ISS service life.

How important are internal temperature gradients in french straws during freezing of bovine sperm in nitrogen vapor?

PubMed

Santos, M V; Sansinena, M; Zaritzky, N; Chirife, J

2013-01-01

The subject of present work was to predict internal temperature gradients developed during freezing of bovine sperm diluted in extender, packaged in 0.5 ml French plastic straws and suspended in static liquid nitrogen vapor at -100 degree C. For this purpose, a mathematical heat transfer model previously developed to predict freezing times (phase change was considered) of semen/extender packaged in straw was extended to predict internal temperature gradients during the cooling/freezing process. Results showed maximum temperature differences between the centre and the periphery of semen/extender "liquid" column was 1.5 degree C for an external heat transfer coefficient, h = 15 W per (m(2) K), and only 0.5 degree C for h = 5 W per (m(2) K). It is concluded that if a thermocouple wire were inserted in a 0.5 ml plastic straw to monitor the freezing process in nitrogen vapor, its radial position would have little importance since expected internal gradients may be safely neglected. This finding facilitates the interpretation of freezing rates in 0.5 ml plastic straws immersed in nitrogen vapor over liquid nitrogen, a widely used method for cryopreservation of bovine spermatozoa.

Curvature Constraints from the Causal Entropic Principle

NASA Astrophysics Data System (ADS)

Bozek, Brandon

2010-01-01

Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The Causal Entropic Principle (Bousso, et al.) provides an alternative approach to anthropic attempts to predict our observed value of the cosmological constant by calculating the entropy created within a causal diamond. We have extended this work to use the Causal Entropic Principle to predict the preferred curvature within the "multiverse." We have found that values larger than ρk = 40*ρm are disfavored by more than 99.99% and a peak value at ρΛ = 7.9*10-123 and ρk =4.3*ρm for open universes. For universes that allow only positive curvature or both positive and negative curvature, we find a correlation between curvature and dark energy that leads to an extended region of preferred values. Our universe is found to be disfavored to an extent depending on the priors on curvature. We also provide a comparison to previous anthropic constraints on open universes and discuss future directions for this work.

Curvature constraints from the causal entropic principle

NASA Astrophysics Data System (ADS)

Bozek, Brandon; Albrecht, Andreas; Phillips, Daniel

2009-07-01

Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The causal entropic principle (Bousso et al.) provides an alternative approach to anthropic attempts to predict our observed value of the cosmological constant by calculating the entropy created within a causal diamond. We have extended this work to use the causal entropic principle to predict the preferred curvature within the “multiverse.” We have found that values larger than ρk=40ρm are disfavored by more than 99.99% peak value at ρΛ=7.9×10-123 and ρk=4.3ρm for open universes. For universes that allow only positive curvature or both positive and negative curvature, we find a correlation between curvature and dark energy that leads to an extended region of preferred values. Our universe is found to be disfavored to an extent depending on the priors on curvature. We also provide a comparison to previous anthropic constraints on open universes and discuss future directions for this work.

Properties of Magnetic Reconnection as a function of magnetic shear

NASA Astrophysics Data System (ADS)

Liu, Y.; Daughton, W. S.; Karimabadi, H.; Li, H.; Gary, S. P.; Guo, F.

2013-12-01

Observations of reconnection events at the Earth's magnetopause and in the solar wind show that reconnection occurs for a large range in magnetic shear angles extending to the very low shear limit 1. Here we report a fully kinetic study of the influence of the magnetic shear on details of reconnection such as its structure and rate. In previous work, we found that the electron diffusion region bifurcates into two or more distinct layers in regimes with weak magnetic shear2, a new feature that may be observable by NASA's up-coming Magnetospheric Multiscale mission. In this work, we have systematically extended the study to lower shear cases and found a new regime, where the reconnection electric field becomes much smaller and the properties of the reconnection changes significantly. We will discuss the role of various physics mechanisms in determining the observed scaling of the reconnection rate, including the dispersive properties of the waves in the system, the dissipation mechanisms and the tearing instability. 1 J. T. Goslings and T. D. Phan. APJL 763, L39, 2013 2 Yi-Hsin Liu et al. Phys. Rev. Lett. 110 , 265004, 2013

The Alliance Negotiation Scale: A psychometric investigation.

PubMed

Doran, Jennifer M; Safran, Jeremy D; Muran, J Christopher

2016-08-01

This study investigates the utility and psychometric properties of a new measure of psychotherapy process, the Alliance Negotiation Scale (ANS; Doran, Safran, Waizmann, Bolger, & Muran, 2012). The ANS was designed to operationalize the theoretical construct of negotiation (Safran & Muran, 2000), and to extend our current understanding of the working alliance concept (Bordin, 1979). The ANS was also intended to improve upon existing measures such as the Working Alliance Inventory (WAI; Horvath & Greenberg, 1986, 1989) and its short form (WAI-S; Tracey & Kokotovic, 1989) by expanding the emphasis on negative therapy process. The present study investigates the psychometric validity of the ANS test scores and interpretation-including confirming its original factor structure and evaluating its internal consistency and construct validity. Construct validity was examined through the ANS' convergence and divergence with several existing scales that measure theoretically related constructs. The results bolster and extend previous findings about the psychometric integrity of the ANS, and begin to illuminate the relationship between negotiation and other important variables in psychotherapy research. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Curvature constraints from the causal entropic principle

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

Bozek, Brandon; Albrecht, Andreas; Phillips, Daniel

2009-07-15

Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The causal entropic principle (Bousso et al.) provides an alternative approach to anthropic attempts to predict our observed value of the cosmological constant by calculating the entropy created within a causal diamond. We have extended this work to use the causal entropic principle to predict the preferred curvature within the 'multiverse'. We have found that values larger than {rho}{sub k}=40{rho}{sub m} are disfavored by more than 99.99% peak value at {rho}{sub {lambda}}=7.9x10{sup -123} and {rho}{sub k}=4.3{rho}{sub m}more » for open universes. For universes that allow only positive curvature or both positive and negative curvature, we find a correlation between curvature and dark energy that leads to an extended region of preferred values. Our universe is found to be disfavored to an extent depending on the priors on curvature. We also provide a comparison to previous anthropic constraints on open universes and discuss future directions for this work.« less

Whither cognitive bias modification research? Commentary on the special section articles.

PubMed

MacLeod, Colin; Koster, Ernst H W; Fox, Elaine

2009-02-01

This commentary reviews key theoretical, methodological, and clinical issues raised by recent research on cognitive bias modification (CBM). The authors identify the major ways in which the new work reported within this special section extends earlier CBM research. In particular, they note that it considers a wider range of participants, includes a greater diversity of symptoms measures, and targets for change a broader array of processing biases than previously has been the case. Furthermore, they point out that the present work develops and employs a more diverse arsenal of bias modification procedures, in some cases delivered across extended periods of time within naturalistic settings. They also draw attention to methodological limitations associated with the current studies, offering recommendations concerning how future CBM research might profitably build upon these exciting new directions while overcoming such limitations. Finally, they evaluate the theoretical and applied implications of the reported findings, discussing their capacity to illuminate the causal contributions made by cognitive bias to emotional vulnerability and their promise concerning the potential therapeutic value of CBM as a clinical tool.

Gender differences in responses to cues presented in the natural environment of cigarette smokers.

PubMed

Wray, Jennifer M; Gray, Kevin M; McClure, Erin A; Carpenter, Matthew J; Tiffany, Stephen T; Saladin, Michael E

2015-04-01

Although the evidence is mixed, female smokers appear to have more difficulty quitting smoking than male smokers. Craving, stress, and negative affect have been hypothesized as potential factors underlying gender differences in quit rates. In the current study, the cue-reactivity paradigm was used to assess craving, stress, and negative affect in response to cues presented in the natural environment of cigarette smokers using ecological momentary assessment. Seventy-six daily smokers (42% female) responded to photographs (smoking, stress, and neutral) presented 4 times per day on an iPhone over the course of 2 weeks. Both smoking and stress cues elicited stronger cigarette craving and stress responses compared to neutral cues. Compared with males, females reported higher levels of post-stress cue craving, stress, and negative affect, but response to smoking cues did not differ by gender. Findings from this project were largely consistent with results from laboratory-based research and extend previous work by measuring response to cues in the natural environment of cigarette smokers. This study extends previous cue reactivity ecological momentary assessment research by using a new platform and by measuring response to stress cues outside of the laboratory. Findings from this project highlight the importance of addressing coping in response to stress cues in clinical settings, especially when working with female smokers. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Understanding visualization: a formal approach using category theory and semiotics.

PubMed

Vickers, Paul; Faith, Joe; Rossiter, Nick

2013-06-01

This paper combines the vocabulary of semiotics and category theory to provide a formal analysis of visualization. It shows how familiar processes of visualization fit the semiotic frameworks of both Saussure and Peirce, and extends these structures using the tools of category theory to provide a general framework for understanding visualization in practice, including: Relationships between systems, data collected from those systems, renderings of those data in the form of representations, the reading of those representations to create visualizations, and the use of those visualizations to create knowledge and understanding of the system under inspection. The resulting framework is validated by demonstrating how familiar information visualization concepts (such as literalness, sensitivity, redundancy, ambiguity, generalizability, and chart junk) arise naturally from it and can be defined formally and precisely. This paper generalizes previous work on the formal characterization of visualization by, inter alia, Ziemkiewicz and Kosara and allows us to formally distinguish properties of the visualization process that previous work does not.

Field singularities at lossless metal-dielectric arbitrary-angle edges and their ramifications to the numerical modeling of gratings.

PubMed

Li, Lifeng

2012-04-01

I extend a previous work [J. Opt. Soc. Am. A, 738 (2011)] on field singularities at lossless metal-dielectric right-angle edges and their ramifications to the numerical modeling of gratings to the case of arbitrary metallic wedge angles. Simple criteria are given that allow one knowing the lossless permittivities and the arbitrary wedge angles to determine if the electric field at the edges is nonsingular, can be regularly singular, or can be irregularly singular without calculating the singularity exponent. Furthermore, the knowledge of the singularity type enables one to predict immediately if a numerical method that uses Fourier expansions of the transverse electric field components at the edges will converge or not without making any numerical tests. All conclusions of the previous work about the general relationships between field singularities, Fourier representation of singular fields, and convergence of numerical methods for modeling lossless metal-dielectric gratings have been reconfirmed.

RF sheaths for arbitrary B field angles

NASA Astrophysics Data System (ADS)

D'Ippolito, Daniel; Myra, James

2014-10-01

RF sheaths occur in tokamaks when ICRF waves encounter conducting boundaries and accelerate electrons out of the plasma. Sheath effects reduce the efficiency of ICRF heating, cause RF-specific impurity influxes from the edge plasma, and increase the plasma-facing component damage. The rf sheath potential is sensitive to the angle between the B field and the wall, the ion mobility and the ion magnetization. Here, we obtain a numerical solution of the non-neutral rf sheath and magnetic pre-sheath equations (for arbitrary values of these parameters) and attempt to infer the parametric dependences of the Child-Langmuir law. This extends previous work on the magnetized, immobile ion regime. An important question is how the rf sheath voltage distributes itself between sheath and pre-sheath for various B field angles. This will show how generally previous estimates of the rf sheath voltage and capacitance were reasonable, and to improve the RF sheath BC. Work supported by US DOE grants DE-FC02-05ER54823 and DE-FG02-97ER54392.

Thermal Timescale Mass Transfer In Binary Population Synthesis

NASA Astrophysics Data System (ADS)

Justham, S.; Kolb, U.

2004-07-01

Studies of binary evolution have, until recently, neglected thermal timescale mass transfer (TTMT). Recent work has suggested that this previously poorly studied area is crucial in the understanding of systems across the compact binary spectrum. We use the state-of-the-art binary population synthesis code BiSEPS (Willems and Kolb, 2002, MNRAS 337 1004-1016). However, the present treatment of TTMT is incomplete due to the nonlinear behaviour of stars in their departure from gravothermal `equilibrium'. Here we show work that should update the ultrafast stellar evolution algorithms within BiSEPS to make it the first pseudo-analytic code that can follow TTMT properly. We have generated fits to a set of over 300 Case B TTMT sequences with a range of intermediate-mass donors. These fits produce very good first approximations to both HR diagrams and mass-transfer rates (see figures 1 and 2), which we later hope to improve and extend. They are already a significant improvement over the previous fits.

Ethnic Enclaves and the Earnings of Immigrants

PubMed Central

Xie, Yu; Gough, Margaret

2011-01-01

A large literature in sociology concerns the implications of immigrants’ participation in ethnic enclaves for their economic and social well-being. The “enclave thesis” speculates that immigrants benefit from working in ethnic enclaves. Previous research concerning the effects of enclave participation on immigrants’ economic outcomes has come to mixed conclusions as to whether enclave effects are positive or negative. In this article, we seek to extend and improve upon past work by formulating testable hypotheses based on the enclave thesis and testing them with data from the 2003 New Immigrant Survey (NIS), employing both residence-based and workplace-based measures of the ethnic enclave. We compare the economic outcomes of immigrants working in ethnic enclaves with those of immigrants working in the mainstream economy. Our research yields minimal support for the enclave thesis. Our results further indicate that for some immigrant groups, ethnic enclave participation actually has a negative effect on economic outcomes. PMID:21863367

Work and Family Characteristics as Predictors of Early Retirement in Married Men and Women

PubMed Central

Kubicek, Bettina; Korunka, Christian; Hoonakker, Peter; Raymo, James M.

2010-01-01

This study presents an integrative model of early retirement using data from the Wisconsin Longitudinal Study. The model extends prior work by incorporating work-family conflict to capture the interaction between the work and family domains and by assuming proximal and distal predictors of early retirement. More precisely, the model suggests that family and job demands and resources predict family-to-work and work-to-family conflict, respectively. All of these factors are presumed to have only indirect effects on retirement timing via the intervening effect of quality of life measures, that is, marital satisfaction, job satisfaction and health. The authors assume that these three factors constitute predictors of early retirement in addition to socioeconomic status and the availability of a pension plan and health insurance. The model was tested with structural equation modeling techniques, and the results were supportive. Therefore, the proposed model offers a general framework for the integration of previous research findings. PMID:21430790

EXTENDED ANALYSIS OF THE SPECTRUM OF SINGLY IONIZED CHROMIUM (Cr II)

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

Sansonetti, Craig J.; Nave, Gillian

2014-08-01

We have made new observations of the spectrum of singly ionized chromium (Cr II) in the region 2850-37900 Å with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. These data extend our previously reported observations in the near-ultra-violet region. We present a comprehensive list of more than 5300 Cr II lines classified as transitions among 456 even and 457 odd levels, 179 of which are newly located in this work. Using highly excited levels of the 3d {sup 4}({sup 5} D)5g, 3d {sup 4}({sup 5} D)6g, and 3d {sup 4}({sup 5}D)6h configurations, we derive an improvedmore » ionization energy of 132971.02 ± 0.12 cm{sup –1} (16.486305 ± 0.000015 eV)« less

Compact illumination optic with three freeform surfaces for improved beam control.

PubMed

Sorgato, Simone; Mohedano, Rubén; Chaves, Julio; Hernández, Maikel; Blen, José; Grabovičkić, Dejan; Benítez, Pablo; Miñano, Juan Carlos; Thienpont, Hugo; Duerr, Fabian

2017-11-27

Multi-chip and large size LEDs dominate the lighting market in developed countries these days. Nevertheless, a general optical design method to create prescribed intensity patterns for this type of extended sources does not exist. We present a design strategy in which the source and the target pattern are described by means of "edge wavefronts" of the system. The goal is then finding an optic coupling these wavefronts, which in the current work is a monolithic part comprising up to three freeform surfaces calculated with the simultaneous multiple surface (SMS) method. The resulting optic fully controls, for the first time, three freeform wavefronts, one more than previous SMS designs. Simulations with extended LEDs demonstrate improved intensity tailoring capabilities, confirming the effectiveness of our method and suggesting that enhanced performance features can be achieved by controlling additional wavefronts.

Diode laser operating on an atomic transition limited by an isotope ⁸⁷Rb Faraday filter at 780 nm.

PubMed

Tao, Zhiming; Hong, Yelong; Luo, Bin; Chen, Jingbiao; Guo, Hong

2015-09-15

We demonstrate an extended cavity Faraday laser system using an antireflection-coated laser diode as the gain medium and the isotope (87)Rb Faraday anomalous dispersion optical filter (FADOF) as the frequency selective device. Using this method, the laser wavelength works stably at the highest transmission peak of the isotope (87)Rb FADOF over the laser diode current from 55 to 140 mA and the temperature from 15°C to 35°C. Neither the current nor the temperature of the laser diode has significant influence on the output frequency. Compared with previous extended cavity laser systems operating at frequencies irrelevant to spectacular atomic transition lines, the laser system realized here provides a stable laser source with the frequency operating on atomic transitions for many practical applications.

Participation of clinical nurses in the practical education of undergraduate nursing students.

PubMed

Cervera-Gasch, Águeda; Gonzalez-Chorda, Víctor M; Mena-Tudela, Desirée; Salas-Medina, Pablo; Folch-Ayora, Ana; Macia-Soler, Loreto

To evaluate the level of participation of clinical nurses from Castellón where Universitat JaumeI nursing students do their clinical clerkship. To identify the variables that may influence clinical nurses' participation in students' clinical mentorship. This observational, cross-sectional and descriptive study was conducted by applying the validated Involvement, Motivation, Satisfaction, Obstacles and Commitment (IMSOC) questionnaire. The variables collected were: age, work environment and previous training. The study was conducted between January and December 2014. The sample included 117 nurses. The overall mean questionnaire score was 122.838 (standard deviation: ±18.692; interquartile range 95%: 119.415-126.26). The variable "previous training for mentorship students" was statistically significant in the overall score and for all dimensions (P<.05). Primary care nurses obtained better scores in the dimension Implication than professionals working at other care levels. The level of participation of the clinical nurses from Castellón is adequate. The previous training that professionals receive for mentoring students improves both their level of participation and primary care level. Extending this research to other national and international environments is recommended. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Sleep and cognitive function of crewmembers and mission controllers working 24-h shifts during a simulated 105-day spaceflight mission

NASA Astrophysics Data System (ADS)

Barger, Laura K.; Wright, Kenneth P.; Burke, Tina M.; Chinoy, Evan D.; Ronda, Joseph M.; Lockley, Steven W.; Czeisler, Charles A.

2014-01-01

The success of long-duration space missions depends on the ability of crewmembers and mission support specialists to be alert and maintain high levels of cognitive function while operating complex, technical equipment. We examined sleep, nocturnal melatonin levels and cognitive function of crewmembers and the sleep and cognitive function of mission controllers who participated in a high-fidelity 105-day simulated spaceflight mission at the Institute of Biomedical Problems (Moscow). Crewmembers were required to perform daily mission duties and work one 24-h extended duration work shift every sixth day. Mission controllers nominally worked 24-h extended duration shifts. Supplemental lighting was provided to crewmembers and mission controllers. Participants' sleep was estimated by wrist-actigraphy recordings. Overall, results show that crewmembers and mission controllers obtained inadequate sleep and exhibited impaired cognitive function, despite countermeasure use, while working extended duration shifts. Crewmembers averaged 7.04±0.92 h (mean±SD) and 6.94±1.08 h (mean±SD) in the two workdays prior to the extended duration shifts, 1.88±0.40 h (mean±SD) during the 24-h work shift, and then slept 10.18±0.96 h (mean±SD) the day after the night shift. Although supplemental light was provided, crewmembers' average nocturnal melatonin levels remained elevated during extended 24-h work shifts. Naps and caffeine use were reported by crewmembers during ˜86% and 45% of extended night work shifts, respectively. Even with reported use of wake-promoting countermeasures, significant impairments in cognitive function were observed. Mission controllers slept 5.63±0.95 h (mean±SD) the night prior to their extended duration work shift. On an average, 89% of night shifts included naps with mission controllers sleeping an average of 3.4±1.0 h (mean±SD) during the 24-h extended duration work shift. Mission controllers also showed impaired cognitive function during extended duration work shifts. These findings indicate that extended duration work shifts present a significant challenge to crewmembers and mission support specialists during long-duration space mission operations. Future research is needed to evaluate the efficacy of alternative work schedules and the development and implementation of more effective countermeasures will be required to maintain high levels of performance.

Reward associations impact both iconic and visual working memory.

PubMed

Infanti, Elisa; Hickey, Clayton; Turatto, Massimo

2015-02-01

Reward plays a fundamental role in human behavior. A growing number of studies have shown that stimuli associated with reward become salient and attract attention. The aim of the present study was to extend these results into the investigation of iconic memory and visual working memory. In two experiments we asked participants to perform a visual-search task where different colors of the target stimuli were paired with high or low reward. We then tested whether the pre-established feature-reward association affected performance on a subsequent visual memory task, in which no reward was provided. In this test phase participants viewed arrays of 8 objects, one of which had unique color that could match the color associated with reward during the previous visual-search task. A probe appeared at varying intervals after stimulus offset to identify the to-be-reported item. Our results suggest that reward biases the encoding of visual information such that items characterized by a reward-associated feature interfere with mnemonic representations of other items in the test display. These results extend current knowledge regarding the influence of reward on early cognitive processes, suggesting that feature-reward associations automatically interact with the encoding and storage of visual information, both in iconic memory and visual working memory. Copyright © 2014 Elsevier Ltd. All rights reserved.

Prerequisites and driving forces behind an extended working life among older workers.

PubMed

Hovbrandt, Pia; Håkansson, Carita; Albin, Maria; Carlsson, Gunilla; Nilsson, Kerstin

2017-11-28

Reforms are changing pension systems in many European countries, in order to both restrict early retirement and force people to extend their working life. From occupational therapy and occupational science perspectives, studies focusing on aspects of working life that motivate the older worker is urgent. The aim was to describe incentives behind an extended working life among people over age 65. Focus group methodology was used, with participants ages 66-71, from varying work fields: construction and technical companies and the municipal elderly care sector. Work was considered important and valuable to the degree of how challenging work was, the possibilities for inclusion in a team of colleagues and the chances for better personal finances. Amongst all, the participants expressed a feeling of a strengthened identity by being challenged and having the opportunity to manage working tasks. The finding showed the actual reasons behind an extended working life among older workers. However, a risk of rising social inequity may appear with increased working life if older people are forced to extend their working life due to a difficult financial situation as a pensioner. A variety of retirement options and initiatives in order to support older workers are justified.

Identification of four novel variants that influence central corneal thickness in multi-ethnic Asian populations.

PubMed

Cornes, Belinda K; Khor, Chiea Chuen; Nongpiur, Monisha E; Xu, Liang; Tay, Wan-Ting; Zheng, Yingfeng; Lavanya, Raghavan; Li, Yang; Wu, Renyi; Sim, Xueling; Wang, Ya-Xing; Chen, Peng; Teo, Yik Ying; Chia, Kee-Seng; Seielstad, Mark; Liu, Jianjun; Hibberd, Martin L; Cheng, Ching-Yu; Saw, Seang-Mei; Tai, E-Shyong; Jonas, Jost B; Vithana, Eranga N; Wong, Tien Y; Aung, Tin

2012-01-15

Central corneal thickness (CCT) is a highly heritable trait. Genes that significantly influence CCT can be candidate genes for common disorders in which CCT has been implicated, such as primary open-angle glaucoma (POAG) and keratoconus. Because the genetic factors controlling CCT in different Asian populations are unclear, we have built on previous work conducted on Singaporean Indians and Malays and extended our hypothesis to individuals of Chinese descent. We have followed up on all suggestive signals of association with CCT (P < 10(-4)) from the previously reported meta-analysis comprising Indians and Malays in a sample of Chinese individuals (n= 2681). In the combined sample (n= 7711), strong evidence of association was observed at four novel loci: IBTK on chromosome 6q14.1; CHSY1 on chromosome 15q26.3; and intergenic regions on chromosomes 7q11.2 and 9p23 (8.01 × 10(-11) < λ(GC) corrected P(meta) < 8.72 × 10(-8)). These four new loci explain an additional 4.3% of the total CCT variance across the sample cohorts over and above that of previously identified loci. We also extend on a previous finding at a fifth locus (AKAP13) where a new single-nucleotide polymorphism (rs1821481, P(meta) = 9.99 × 10(-9)) was found to be significantly more informative compared with the previously reported rs6496932 (P(meta) = 3.64 × 10(-5)). Performing association analysis in Asians may lead to the discovery of ethnic-specific genes that control CCT, offering further mechanistic insights into the regulation of CCT. In addition, it may also provide several candidate genes for interrogation for POAG, keratoconus and possible racial/ethnic variations. © The Author 2011. Published by Oxford University Press. All rights reserved.

Child maltreatment among U.S. Air Force parents deployed in support of Operation Iraqi Freedom/Operation Enduring Freedom.

PubMed

Rabenhorst, Mandy M; McCarthy, Randy J; Thomsen, Cynthia J; Milner, Joel S; Travis, Wendy J; Colasanti, Marie P

2015-02-01

This study examined child maltreatment perpetration among 99,697 active-duty U.S. Air Force parents who completed a combat deployment. Using the deploying parent as the unit of analysis, we analyzed whether child maltreatment rates increased postdeployement relative to predeployment. These analyses extend previous research that used aggregate data and extend our previous work that used data from the same period but used the victim as the unit of analysis and included only deploying parents who engaged in child maltreatment. In this study, 2% (n = 1,746) of deploying parents perpetrated child maltreatment during the study period. Although no overall differences were found in child maltreatment rates postdeployment compared to predeployment, several maltreatment-related characteristics qualified this finding. Rates for emotional abuse and mild maltreatment were lower following deployment, whereas child maltreatment rates for severe maltreatment were higher following deployment. The finding that rates of severe child maltreatment, including incidents involving alcohol use, were higher postdeployment suggests a need for additional support services for parents following their return from combat deployment, with a focus on returning parents who have an alcohol use problem. © The Author(s) 2014.

Racial bias in sport medical staff's perceptions of others' pain.

PubMed

Druckman, James N; Trawalter, Sophie; Montes, Ivonne; Fredendall, Alexandria; Kanter, Noah; Rubenstein, Allison Paige

2017-11-27

Unequal treatment based on race is well documented in higher education and healthcare settings. In the present work, we examine racial bias at the intersection of these domains: racial bias in pain-related perceptions among National Collegiate Athletic Association (NCAA) Division 1 sport medical staff. Using experimental vignettes about a student-athlete who injured his/her anterior cruciate ligament (ACL), we find, like prior work, that respondents perceived Black (vs. White) targets as having higher initial pain tolerance. Moreover, this bias was mediated by perceptions of social class. We extend prior work by showing racial bias was not evident on other outcome measures, including perception of recovery process pain, likelihood of over-reporting pain, and over-use of drugs to combat pain. This suggests stricter boundary conditions on bias in pain perceptions than had been previously recognized.

Self-reported emotional intelligence, burnout and engagement among staff in services for people with intellectual disabilities.

PubMed

Durán, Auxiliadora; Extremera, Natalio; Rey, Lourdes

2004-10-01

This study examined the relationship among dimensions of self-reported Emotional Intelligence, Engagement and Burnout, using the Trait Meta-Mood Scale, Maslach Burnout Inventory and Utrecht Work Engagement Scale in a sample of Spanish professionals who work at institutions for people with intellectual disabilities. The results showed that Emotional Clarity was significantly associated with Personal Accomplishment (r=.25) and Dedication (r=.25). Further, Repair to moods was significantly correlated with all Engagement dimensions (.20 Vigor, .30 Dedication, .36 Absorption) and with Personal Accomplishment (.31). These findings extend previous research with college students in which Clarity and Repair to moods subscales were relevant predictors of well-being indexes and interpersonal functioning and suggest that the Trait Meta-Mood Scale subscales also show significant relationships with emotional functioning and work-related variables in a professional sample.

Simulations of Turbulence in Tokamak Edge and Effects of Self-Consistent Zonal Flows

NASA Astrophysics Data System (ADS)

Cohen, Bruce; Umansky, Maxim

2013-10-01

Progress is reported on simulations of electromagnetic drift-resistive ballooning turbulence in the tokamak edge. This extends previous work to include self-consistent zonal flows and their effects. The previous work addressed simulation of L-mode tokamak edge turbulence using the turbulence code BOUT that solves Braginskii-based plasma fluid equations in tokamak edge domain. The calculations use realistic single-null geometry and plasma parameters of the DIII-D tokamak and produce fluctuation amplitudes, fluctuation spectra, and particle and thermal fluxes that compare favorably to experimental data. In the effect of sheared ExB poloidal rotation is included with an imposed static radial electric field fitted to experimental data. In the new work here we include the radial electric field self-consistently driven by the microturbulence, which contributes to the sheared ExB poloidal rotation (zonal flow generation). We present simulations with/without zonal flows for both cylindrical geometry, as in the UCLA Large Plasma Device, and for the DIII-D tokamak L-mode cases in to quantify the influence of self-consistent zonal flows on the microturbulence and the concomitant transport. This work was performed under the auspices of the U.S. Department of Energy under contract DE-AC52-07NA27344 at the Lawrence Livermore National Laboratory.

Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

NASA Astrophysics Data System (ADS)

Aab, A.; Abreu, P.; Aglietta, M.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Anastasi, G. A.; Anchordoqui, L.; Andrada, B.; Andringa, S.; Aramo, C.; Arqueros, F.; Arsene, N.; Asorey, H.; Assis, P.; Aublin, J.; Avila, G.; Badescu, A. M.; Balaceanu, A.; Barbato, F.; Barreira Luz, R. J.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Biermann, P. L.; Biteau, J.; Blaess, S. G.; Blanco, A.; Blazek, J.; Bleve, C.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Borodai, N.; Botti, A. M.; Brack, J.; Brancus, I.; Bretz, T.; Bridgeman, A.; Briechle, F. L.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, L.; Cancio, A.; Canfora, F.; Caramete, L.; Caruso, R.; Castellina, A.; Catalani, F.; Cataldi, G.; Cazon, L.; Chavez, A. G.; Chinellato, J. A.; Chudoba, J.; Clay, R. W.; Cobos, A.; Colalillo, R.; Coleman, A.; Collica, L.; Coluccia, M. R.; Conceição, R.; Consolati, G.; Contreras, F.; Cooper, M. J.; Coutu, S.; Covault, C. E.; Cronin, J.; D'Amico, S.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Jong, S. J.; De Mauro, G.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; Debatin, J.; Deligny, O.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; D'Olivo, J. C.; Dorosti, Q.; dos Anjos, R. C.; Dova, M. T.; Dundovic, A.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Falcke, H.; Farmer, J.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Fenu, F.; Fick, B.; Figueira, J. M.; Filipčič, A.; Fratu, O.; Freire, M. M.; Fujii, T.; Fuster, A.; Gaior, R.; García, B.; Garcia-Pinto, D.; Gaté, F.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glaser, C.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P. F.; González, N.; Gorgi, A.; Gorham, P.; Grillo, A. F.; Grubb, T. D.; Guarino, F.; Guedes, G. P.; Halliday, R.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huege, T.; Hulsman, J.; Insolia, A.; Isar, P. G.; Jandt, I.; Johnsen, J. A.; Josebachuili, M.; Jurysek, J.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Keilhauer, B.; Kemmerich, N.; Kemp, E.; Kemp, J.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Kuempel, D.; Kukec Mezek, G.; Kunka, N.; Kuotb Awad, A.; Lago, B. L.; LaHurd, D.; Lang, R. G.; Lauscher, M.; Legumina, R.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lo Presti, D.; Lopes, L.; López, R.; López Casado, A.; Lorek, R.; Luce, Q.; Lucero, A.; Malacari, M.; Mallamaci, M.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Mariş, I. C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Melo, D.; Menshikov, A.; Merenda, K.-D.; Michal, S.; Micheletti, M. I.; Middendorf, L.; Miramonti, L.; Mitrica, B.; Mockler, D.; Mollerach, S.; Montanet, F.; Morello, C.; Mostafá, M.; Müller, A. L.; Müller, G.; Muller, M. A.; Müller, S.; Mussa, R.; Naranjo, I.; Nellen, L.; Nguyen, P. H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Núñez, L. A.; Ochilo, L.; Oikonomou, F.; Olinto, A.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Paul, T.; Pech, M.; Pedreira, F.; Pekala, J.; Pelayo, R.; Peña-Rodriguez, J.; Pereira, L. A. S.; Perlin, M.; Perrone, L.; Peters, C.; Petrera, S.; Phuntsok, J.; Piegaia, R.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Ramos-Pollan, R.; Rautenberg, J.; Ravignani, D.; Ridky, J.; Riehn, F.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Fernandez, G.; Rodriguez Rojo, J.; Rogozin, D.; Roncoroni, M. J.; Roth, M.; Roulet, E.; Rovero, A. C.; Ruehl, P.; Saffi, S. J.; Saftoiu, A.; Salamida, F.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sánchez, F.; Sanchez-Lucas, P.; Santos, E. M.; Santos, E.; Sarazin, F.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Schauer, M.; Scherini, V.; Schieler, H.; Schimp, M.; Schmidt, D.; Scholten, O.; Schovánek, P.; Schröder, F. G.; Schröder, S.; Schulz, A.; Schumacher, J.; Sciutto, S. J.; Segreto, A.; Shadkam, A.; Shellard, R. C.; Sigl, G.; Silli, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Smith, B.; Snow, G. R.; Sommers, P.; Sonntag, S.; Squartini, R.; Stanca, D.; Stanič, S.; Stasielak, J.; Stassi, P.; Stolpovskiy, M.; Strafella, F.; Streich, A.; Suarez, F.; Suarez Durán, M.; Sudholz, T.; Suomijärvi, T.; Supanitsky, A. D.; Šupík, J.; Swain, J.; Szadkowski, Z.; Taboada, A.; Taborda, O. A.; Theodoro, V. M.; Timmermans, C.; Todero Peixoto, C. J.; Tomankova, L.; Tomé, B.; Torralba Elipe, G.; Travnicek, P.; Trini, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van Bodegom, P.; van den Berg, A. M.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vázquez, R. A.; Veberič, D.; Ventura, C.; Vergara Quispe, I. D.; Verzi, V.; Vicha, J.; Villaseñor, L.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weindl, A.; Wiencke, L.; Wilczyński, H.; Wileman, C.; Wirtz, M.; Wittkowski, D.; Wundheiler, B.; Yang, L.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zong, Z.; Zuccarello, F.; Pierre Auger Collaboration

2017-12-01

We present a new method for probing the hadronic interaction models at ultrahigh energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air showers. Using the risetimes of the recorded signals, we define a new parameter, which we use to compare our observations with predictions from simulations. We find, first, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies. Second, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum Xmax for a sample of over 81,000 events extending from 0.3 to over 100 EeV. Above 30 EeV, the sample is nearly 14 times larger than what is currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of ⟨Xmax⟩ is compared to simulations and interpreted in terms of the mean of the logarithmic mass. We find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.

Time-discretized steady compressible Navier-Stokes equations with inflow and outflow boundaries

NASA Astrophysics Data System (ADS)

Yoon, Gangjoon; Yang, Sung-Dae; Song, Minsu; Gunzburger, Max

2013-12-01

The time-discretized steady compressible Navier-Stokes equations in n-dimensional bounded domains with the velocity specified only at the inflow boundary are considered. The existence and uniqueness of L p solutions are proved for p > n. For time-discretized steady flows, results of Kweon and Kellogg and of Kweon and Song are extended in a manner that allows for more general domains and for density-dependent viscosity coefficients. Moreover, we only require p > n which is a critical barrier in the previous works.

The Make 2D-DB II package: conversion of federated two-dimensional gel electrophoresis databases into a relational format and interconnection of distributed databases.

PubMed

Mostaguir, Khaled; Hoogland, Christine; Binz, Pierre-Alain; Appel, Ron D

2003-08-01

The Make 2D-DB tool has been previously developed to help build federated two-dimensional gel electrophoresis (2-DE) databases on one's own web site. The purpose of our work is to extend the strength of the first package and to build a more efficient environment. Such an environment should be able to fulfill the different needs and requirements arising from both the growing use of 2-DE techniques and the increasing amount of distributed experimental data.

Application of Copper Indium Gallium Diselenide Photovoltaic Cells to Extend the Endurance and Capabilities of the Raven RQ-11B Unmanned Aerial Vehicle

DTIC Science & Technology

2010-09-01

POWER POINT TRACKER A more suitable component used in photovoltaic appli- cations is the Maximum Power Point Tracker ( MPPT ). An MPPT ... MPPT / power converter (Solar Charge Controller ) weighed 6.5-Oz, but without the casing it weighed only 3.6-Oz. We preferred to use it without the...for this test was the GV-4 Low Power Charge Controller from GENASUN used in previous the- sis work [5]. This MPPT was programmed to charge up

Hybrid Discrete-Continuous Markov Decision Processes

NASA Technical Reports Server (NTRS)

Feng, Zhengzhu; Dearden, Richard; Meuleau, Nicholas; Washington, Rich

2003-01-01

This paper proposes a Markov decision process (MDP) model that features both discrete and continuous state variables. We extend previous work by Boyan and Littman on the mono-dimensional time-dependent MDP to multiple dimensions. We present the principle of lazy discretization, and piecewise constant and linear approximations of the model. Having to deal with several continuous dimensions raises several new problems that require new solutions. In the (piecewise) linear case, we use techniques from partially- observable MDPs (POMDPS) to represent value functions as sets of linear functions attached to different partitions of the state space.

The optimal manufacturing batch size with rework under time-varying demand process for a finite time horizon

NASA Astrophysics Data System (ADS)

Musa, Sarah; Supadi, Siti Suzlin; Omar, Mohd

2014-07-01

Rework is one of the solutions to some of the main issues in reverse logistic and green supply chain as it reduces production cost and environmental problem. Many researchers focus on developing rework model, but to the knowledge of the author, none of them has developed a model for time-varying demand rate. In this paper, we extend previous works and develop multiple batch production system for time-varying demand rate with rework. In this model, the rework is done within the same production cycle.

Polyglutamine Disease Modeling: Epitope Based Screen for Homologous Recombination using CRISPR/Cas9 System.

PubMed

An, Mahru C; O'Brien, Robert N; Zhang, Ningzhe; Patra, Biranchi N; De La Cruz, Michael; Ray, Animesh; Ellerby, Lisa M

2014-04-15

We have previously reported the genetic correction of Huntington's disease (HD) patient-derived induced pluripotent stem cells using traditional homologous recombination (HR) approaches. To extend this work, we have adopted a CRISPR-based genome editing approach to improve the efficiency of recombination in order to generate allelic isogenic HD models in human cells. Incorporation of a rapid antibody-based screening approach to measure recombination provides a powerful method to determine relative efficiency of genome editing for modeling polyglutamine diseases or understanding factors that modulate CRISPR/Cas9 HR.

Euler-Lagrange formulas for pseudo-Kähler manifolds

NASA Astrophysics Data System (ADS)

Park, JeongHyeong

2016-01-01

Let c be a characteristic form of degree k which is defined on a Kähler manifold of real dimension m > 2 k. Taking the inner product with the Kähler form Ωk gives a scalar invariant which can be considered as a generalized Lovelock functional. The associated Euler-Lagrange equations are a generalized Einstein-Gauss-Bonnet gravity theory; this theory restricts to the canonical formalism if c =c2 is the second Chern form. We extend previous work studying these equations from the Kähler to the pseudo-Kähler setting.

Progress of Rugby Hohlraum Experiments on Omega

NASA Astrophysics Data System (ADS)

Philippe, Franck; Tassin, Veronique; Casner, Alexis; Gauthier, Pascal; Seytor, Patricia; Monteil, Marie-Christine; Park, Hye-Sook; Robey, Harry; Ross, Steven; Amendt, Peter; Girard, Frederic; Villette, Bruno; Reverdin, Charles; Loiseau, Pascal; Caillaud, Tony; Landoas, Olivier; Li, Chi Kang; Petrasso, Richard; Seguin, Fredrick; Rosenberg, Markus

2011-10-01

The rugby hohlraum concept is predicted to enable better coupling and higher gains in the indirect drive approach to ignition. A collaborative experimental program is currently pursued on OMEGA to test this concept in preparation for future megajoule-scale ignition designs. A direct comparison of gas-filled rugby hohlraums with classical cylinders was recently performed, showing a significant (up to ~40%) observed x-ray drive enhancement and neutron yields that are consistently higher in the rugby case. This work extends and confirms our previous findings in empty rugby hohlraums.

Relativistic thermal plasmas - Effects of magnetic fields

NASA Technical Reports Server (NTRS)

Araki, S.; Lightman, A. P.

1983-01-01

Processes and equilibria in finite, relativistic, thermal plasmas are investigated, taking into account electron-positron creation and annihilation, photon production by internal processes, and photon production by a magnetic field. Inclusion of the latter extends previous work on such plasmas. The basic relations for thermal, Comptonized synchrotron emission are analyzed, including emission and absorption without Comptonization, Comptonized thermal synchrotron emission, and the Comptonized synchrotron and bremsstrahlung luminosities. Pair equilibria are calculated, including approximations and dimensionless parameters, the pair balance equation, maximum temperatures and field strengths, and individual models and cooling curves.

Resuscitation of the newly born infant: an advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation.

PubMed

Kattwinkel, J; Niermeyer, S; Nadkarni, V; Tibballs, J; Phillips, B; Zideman, D; Van Reempts, P; Osmond, M

1999-04-01

The International Liaison Committee on Resuscitation (ILCOR), with representation from North America, Europe, Australia, New Zealand, Africa, and South America, was formed in 1992 to provide a forum for liaison between resuscitation organizations in the developed world. This consensus document on resuscitation extends previously published ILCOR advisory statements on resuscitation to address the unique and changing physiology of the newly born infant within the first few hours following birth and the techniques for providing advanced life support.

Efficient Planning of Wind-Optimal Routes in North Atlantic Oceanic Airspace

NASA Technical Reports Server (NTRS)

Rodionova, Olga; Sridhar, Banavar

2017-01-01

The North Atlantic oceanic airspace (NAT) is crossed daily by more than a thousand flights, which are greatly affected by strong jet stream air currents. Several studies devoted to generating wind-optimal (WO) aircraft trajectories in the NAT demonstrated great efficiency of such an approach for individual flights. However, because of the large separation norms imposed in the NAT, previously proposed WO trajectories induce a large number of potential conflicts. Much work has been done on strategic conflict detection and resolution (CDR) in the NAT. The work presented here extends previous methods and attempts to take advantage of the NAT traffic structure to simplify the problem and improve the results of CDR. Four approaches are studied in this work: 1) subdividing the existing CDR problem into sub-problems of smaller sizes, which are easier to handle; 2) more efficient data reorganization within the considered time period; 3) problem localization, i.e. concentrating the resolution effort in the most conflicted regions; 4) applying CDR to the pre-tactical decision horizon (a couple of hours in advance). Obtained results show that these methods efficiently resolve potential conflicts at the strategic and pre-tactical levels by keeping the resulting trajectories close to the initial WO ones.

The Resistance of Spheres in Wind Tunnels and In Air

NASA Technical Reports Server (NTRS)

Bacon, D L; Reid, E G

1924-01-01

To supplement the standardization tests now in progress at several laboratories, a broad investigation of the resistance of spheres in wind tunnels and free air has been carried out by the National Advisory Committee for Aeronautics. The subject has been classed in aerodynamic research, and in consequence there is available a great mass of data from previous investigations. This material was given careful consideration in laying out the research, and explanation of practically all the disagreement between former experiments has resulted. A satisfactory confirmation of Reynolds law has been accomplished, the effect of means of support determined, the range of experiment greatly extended by work in the new variable density wind tunnel, and the effects of turbulence investigated by work in the tunnels and by towing and dropping tests in free air. It is concluded that the erratic nature of most of the previous work is due to support interference and differing turbulence conditions. While the question of support has been investigated thoroughly, a systematic and comprehensive study of the effects of scale and quality of turbulence will be necessary to complete the problem, as this phase was given only general treatment.

Emotional reactivity across the adult life span: the cognitive pragmatics make a difference.

PubMed

Kunzmann, Ute; Richter, David

2009-12-01

Previously, we found that during films about age-typical losses, older adults experienced greater sadness than young adults, whereas their physiological responses were just as large. In the present study, our goal was to replicate this finding and extend past work by examining the role of cognitive functioning in age differences in emotional reactivity. We measured the autonomic and subjective responses of 240 adults (age range=20 to 70) while they viewed films about age-typical losses from our previous work. Findings were fully supportive of our past work: The magnitude of subjective reactions to our films increased linearly over the adult years, whereas there were no age differences on the level of physiological reactivity. We also found that the subjective reactions of adults with high pragmatic intelligence were of moderate size independent of their own age or the age relevance of the emotion elicitor. In contrast, the subjective reactions of adults low on pragmatic intelligence were more variable. Together, this evidence suggests that research on age differences in emotional reactivity may benefit from a perspective that considers individual difference variables as well as contextual variations. PsycINFO Database Record Copyright (c) 2009 APA, all rights reserved

Reciprocal Family, Friendship and Church Support Networks of African Americans: Findings from the National Survey of American Life.

PubMed

Taylor, Robert Joseph; Mouzon, Dawne M; Nguyen, Ann W; Chatters, Linda M

2016-12-01

This study examined reciprocal support networks involving extended family, friends and church members among African Americans. Our analysis examined specific patterns of reciprocal support (i.e., received only, gave only, both gave and received, neither gave or received), as well as network characteristics (i.e., contact and subjective closeness) as correlates of reciprocal support. The analysis is based on the African American sub-sample of the National Survey of American Life (NSAL). Overall, our findings indicate that African Americans are very involved in reciprocal support networks with their extended family, friends and church members. Respondents were most extensively involved in reciprocal supports with extended family members, followed closely by friends and church networks. Network characteristics (i.e., contact and subjective closeness) were significantly and consistently associated with involvement with reciprocal support exchanges for all three networks. These and other findings are discussed in detail. This study complements previous work on the complementary roles of family, friend and congregational support networks, as well as studies of racial differences in informal support networks.

Rurality/Urbanism and Extended Familism Among Working- and Lower-Class Blacks.

ERIC Educational Resources Information Center

Dietrich, Katheryn Thomas

A comprehensive look is taken at the rural-urban variation in extended familism among a segment of the population for which extended familism purportedly is especially salient: lower and working class black Americans. The study is guided by the general hypothesis that rurality/urbanism affects extended familism when nonecological variables are…

The Development of a Factorizable Multigrid Algorithm for Subsonic and Transonic Flow

NASA Technical Reports Server (NTRS)

Roberts, Thomas W.

2001-01-01

The factorizable discretization of Sidilkover for the compressible Euler equations previously demonstrated for channel flows has been extended to external flows.The dissipation of the original scheme has been modified to maintain stability for moderately stretched grids. The discrete equations are solved by symmetric collective Gauss-Seidel relaxation and FAS multigrid. Unlike the earlier work ordering the grid vertices in the flow direction has been found to be unnecessary. Solutions for essential incompressible flow (Mach 0.01) and supercritical flows have obtained for a Karman-Trefftz airfoil with it conformally mapped grid,as well as a NACA 0012 on an algebraically generated grid. The current work demonstrates nearly 0(n) convergence for subsonic and slightly transonic flows.

Control of flexible beams using a free-free active truss

NASA Technical Reports Server (NTRS)

Clark, W. W.; Kimiavi, B.; Robertshaw, H. H.

1989-01-01

An analytical and experimental study involving controlling flexible beams using a free-free active truss is presented. This work extends previous work in controlling flexible continua with active trusses which were configured with fixed-free boundary conditions. The following describes the Lagrangian approach used to derive the equations of motion for the active truss and the beams attached to it. A partial-state feedback control law is derived for this system based on a full-state feedback Linear Quadratic Regulator method. The analytical model is examined via numerical simulations and the results are compared to a similar experimental apparatus described herein. The results show that control of a flexible continua is possible with a free-free active truss.

Sensor Webs with a Service-Oriented Architecture for On-demand Science Products

NASA Technical Reports Server (NTRS)

Mandl, Daniel; Ungar, Stephen; Ames, Troy; Justice, Chris; Frye, Stuart; Chien, Steve; Tran, Daniel; Cappelaere, Patrice; Derezinsfi, Linda; Paules, Granville;

Impacts of extended working hours in logging

Treesearch

Dana Mitchell; Tom Gallagher

2008-01-01

Last year at the 2007 AIM in Minneapolis, MN, the authors presented the human factors impacts to consider when implementing extended working hours in the logging industry. In a continuation of this project, we have researched existing literature to identify possible actions that logging business owners can take to reduce the impact of extended working hours on their...

Does organisational justice protect from sickness absence following a major life event? A Finnish public sector study.

PubMed

Elovainio, M; Kivimäki, M; Linna, A; Brockner, J; van den Bos, K; Greenberg, J; Pentti, J; Virtanen, M; Vahtera, J

2010-05-01

It has been shown that fairness perceptions have a strong impact on health, especially under conditions of great work stress. The aim of this study was to extend previous research in studying whether working in high justice workplace would protect from health effects following environmental stressors outside work. Using a prospective longitudinal design, the relationships between organisational justice and sickness-related absences both before and after a major life event among 25 459 public sector employees working in 2551 work units were studied. Sickness absences covered the period from 36 months before the event until 30 months after the event. The increase in sickness absences after the event was larger and stayed at a higher level even 30 months after the event, among those who perceived the management practices in their work unit to be relatively unfair. Similar patterns were found for each of the distributive, procedural and interactional dimensions of organisational justice. Fair organisational and managerial procedures may buffer the negative health effects of psychosocial health risks outside work.

An In-depth Chandra ACIS View Of The Circumnuclear Region Of NGC 4151: The Jet, The Biconical Outflow, And A Leaky Torus

NASA Astrophysics Data System (ADS)

Wang, Junfeng; Fabbiano, G.; Elvis, M.; Risaliti, G.; Karovska, M.; Zezas, A.; Mundell, C. G.

2011-05-01

We report on the imaging analysis of 200 ks Chandra ACIS-S observations of the nearby Seyfert 1 galaxy NGC 4151. Structured soft X-ray emission is observed to extend from 30 pc to 1.5 kpc. We find strong evidence for jet-gas cloud interaction in the inner 150 pc region, confirming our previous HRC results. Self-consistent photoionization models provide good descriptions of the spectra of the optical bi-cone, supporting the dominant role of nuclear photoionization. Presence of both low and high ionization spectral components and extended emission in the X-ray image perpendicular to the bi-cone indicates leakage of nuclear ionization. Using spatially resolved features, we estimate the kinematic power of the outflow in NGC 4151 to be 0.3% of its bolometric luminosity. This work is supported by NASA grant GO8-9101X and GO1-12009X.

Kalman and particle filtering methods for full vehicle and tyre identification

NASA Astrophysics Data System (ADS)

Bogdanski, Karol; Best, Matthew C.

2018-05-01

This paper considers identification of all significant vehicle handling dynamics of a test vehicle, including identification of a combined-slip tyre model, using only those sensors currently available on most vehicle controller area network buses. Using an appropriately simple but efficient model structure, all of the independent parameters are found from test vehicle data, with the resulting model accuracy demonstrated on independent validation data. The paper extends previous work on augmented Kalman Filter state estimators to concentrate wholly on parameter identification. It also serves as a review of three alternative filtering methods; identifying forms of the unscented Kalman filter, extended Kalman filter and particle filter are proposed and compared for effectiveness, complexity and computational efficiency. All three filters are suited to applications of system identification and the Kalman Filters can also operate in real-time in on-line model predictive controllers or estimators.

Interrelations and moderators of longitudinal links between marital satisfaction and depressive symptoms among couples in established relationships.

PubMed

Kouros, Chrystyna D; Papp, Lauren M; Cummings, E Mark

2008-10-01

Extending research based on newlywed couples, this study investigated longitudinal associations between marital satisfaction and depressive symptoms in a community sample of 296 couples in established relationships (M = 13.25 years, SD = 5.98) with children (M age = 11.05 years, SD = 2.31). Support was found for reciprocal relations between marital satisfaction and depressive symptoms in couples with established relationships. Further extending previous work, the study showed that relationship length and hostile marital conflict were significant moderators of these linkages. Husbands in longer term relationships were more vulnerable to depressive symptoms in the context of marital problems compared with husbands in shorter term relationships. At higher levels of marital conflict, the negative relationship between marital satisfaction and depressive symptoms was strengthened. Reflecting an unexpected finding, increased conflict buffered spouses from marital dissatisfaction in the context of depressive symptoms. Copyright 2008 APA, all rights reserved.

New exponential synchronization criteria for time-varying delayed neural networks with discontinuous activations.

PubMed

Cai, Zuowei; Huang, Lihong; Zhang, Lingling

2015-05-01

This paper investigates the problem of exponential synchronization of time-varying delayed neural networks with discontinuous neuron activations. Under the extended Filippov differential inclusion framework, by designing discontinuous state-feedback controller and using some analytic techniques, new testable algebraic criteria are obtained to realize two different kinds of global exponential synchronization of the drive-response system. Moreover, we give the estimated rate of exponential synchronization which depends on the delays and system parameters. The obtained results extend some previous works on synchronization of delayed neural networks not only with continuous activations but also with discontinuous activations. Finally, numerical examples are provided to show the correctness of our analysis via computer simulations. Our method and theoretical results have a leading significance in the design of synchronized neural network circuits involving discontinuous factors and time-varying delays. Copyright © 2015 Elsevier Ltd. All rights reserved.

The mosses (Bryophyta) of Capitán Prat Province, Aisén Region, southern Chile.

PubMed

Larraín, Juan

2016-01-01

The bryophytes of Capitán Prat province have remained one of the least explored in Chile. The eventual construction of several dams on the rivers Baker and Pascua required prospection of all groups of organisms including bryophytes, work that was facilitated by the recent construction of vehicular roads that now offer easy access to previously almost unaccessible locations. The results of intense bryophyte collecting during the austral summer of 2007 are here presented. A total of 260 moss taxa are reported for the province, corresponding to 256 species and four infraspecific taxa, of which 211 are new records for the province, 54 are new for Aisén Region, and two are new records for continental Chile ( Pohlia longicollis (Hedw.) Lindb. and Rigodium toxarion var. robustum (Broth.) Zomlefer). Twelve species extend their known distribution ranges to the north, whereas 49 extend them to the south.

The mosses (Bryophyta) of Capitán Prat Province, Aisén Region, southern Chile

PubMed Central

Larraín, Juan

2016-01-01

Abstract The bryophytes of Capitán Prat province have remained one of the least explored in Chile. The eventual construction of several dams on the rivers Baker and Pascua required prospection of all groups of organisms including bryophytes, work that was facilitated by the recent construction of vehicular roads that now offer easy access to previously almost unaccessible locations. The results of intense bryophyte collecting during the austral summer of 2007 are here presented. A total of 260 moss taxa are reported for the province, corresponding to 256 species and four infraspecific taxa, of which 211 are new records for the province, 54 are new for Aisén Region, and two are new records for continental Chile (Pohlia longicollis (Hedw.) Lindb. and Rigodium toxarion var. robustum (Broth.) Zomlefer). Twelve species extend their known distribution ranges to the north, whereas 49 extend them to the south. PMID:27698577

Surface mass diffusion over an extended temperature range on Pt(111)

NASA Astrophysics Data System (ADS)

Rajappan, M.; Swiech, W.; Ondrejcek, M.; Flynn, C. P.

2007-06-01

Surface mass diffusion is investigated on Pt(111) at temperatures in the range 710-1220 K. This greatly extends the range over which diffusion is known from step fluctuation spectroscopy (SFS). In the present research, a beam of Pt- self-ions is employed to create a suitable structure on step edges. The surface mass diffusion coefficients then follow from the decay of Fourier components observed by low-energy electron microscopy (LEEM) at selected annealing temperatures. The results agree with SFS values where they overlap, and continue smoothly to low temperature. This makes it unlikely that diffusion along step edges plays a major role in step edge relaxation through the temperature range studied. The surface mass diffusion coefficient for the range 710-1520 K deduced from the present work, together with previous SFS data, is Ds = 4 × 10-3 exp(-1.47 eV/kBT) cm2 s-1.

Visible and Extended Near-Infrared Multispectral Imaging for Skin Cancer Diagnosis

PubMed Central

Rey-Barroso, Laura; Burgos-Fernández, Francisco J.; Delpueyo, Xana; Ares, Miguel; Malvehy, Josep; Puig, Susana

2018-01-01

With the goal of diagnosing skin cancer in an early and noninvasive way, an extended near infrared multispectral imaging system based on an InGaAs sensor with sensitivity from 995 nm to 1613 nm was built to evaluate deeper skin layers thanks to the higher penetration of photons at these wavelengths. The outcomes of this device were combined with those of a previously developed multispectral system that works in the visible and near infrared range (414 nm–995 nm). Both provide spectral and spatial information from skin lesions. A classification method to discriminate between melanomas and nevi was developed based on the analysis of first-order statistics descriptors, principal component analysis, and support vector machine tools. The system provided a sensitivity of 78.6% and a specificity of 84.6%, the latter one being improved with respect to that offered by silicon sensors. PMID:29734747

Maternal pre-pregnancy obesity and risk for inattention and negative emotionality in children.

PubMed

Rodriguez, Alina

2010-02-01

This study aimed to replicate and extend previous work showing an association between maternal pre-pregnancy adiposity and risk for attention deficit hyperactivity disorder (ADHD) symptoms in children. A Swedish population-based prospective pregnancy-offspring cohort was followed up when children were 5 years old (N = 1,714). Mothers and kindergarten teachers rated children's ADHD symptoms, presence and duration of problems, and emotionality. Dichotomized outcomes examined difficulties of clinical relevance (top 15% of the distribution). Analyses adjusted for pregnancy (maternal smoking, depressive symptoms, life events, education, age, family structure), birth outcomes (birth weight, gestational age, infant sex) and concurrent variables (family structure, maternal depressive symptoms, parental ADHD symptoms, and child overweight) in an attempt to rule out confounding. Maternal pre-pregnancy overweight and obesity predicted high inattention symptom scores and obesity was associated with a two-fold increase in risk of difficulties with emotion intensity and emotion regulation according to teacher reports. Means of maternal ratings were unrelated to pre-pregnancy body mass index (BMI). Presence and duration of problems were associated with both maternal over and underweight according to teachers. Despite discrepancies between maternal and teacher reports, these results provide further evidence that maternal pre-pregnancy overweight and obesity are associated with child inattention symptoms and extend previous work by establishing a link between obesity and emotional difficulties. Maternal adiposity at the time of conception may be instrumental in programming child mental health, as prenatal brain development depends on maternal energy supply. Possible mechanisms include disturbed maternal metabolic function. If maternal pre-pregnancy obesity is a causal risk factor, the potential for prevention is great.

The impact of premorbid and current intellect in schizophrenia: cognitive, symptom, and functional outcomes

PubMed Central

Wells, Ruth; Swaminathan, Vaidy; Sundram, Suresh; Weinberg, Danielle; Bruggemann, Jason; Jacomb, Isabella; Cropley, Vanessa; Lenroot, Rhoshel; Pereira, Avril M; Zalesky, Andrew; Bousman, Chad; Pantelis, Christos; Weickert, Cynthia Shannon; Weickert, Thomas W

2015-01-01

Background: Cognitive heterogeneity among people with schizophrenia has been defined on the basis of premorbid and current intelligence quotient (IQ) estimates. In a relatively large, community cohort, we aimed to independently replicate and extend cognitive subtyping work by determining the extent of symptom severity and functional deficits in each group. Methods: A total of 635 healthy controls and 534 patients with a diagnosis of schizophrenia or schizoaffective disorder were recruited through the Australian Schizophrenia Research Bank. Patients were classified into cognitive subgroups on the basis of the Wechsler Test of Adult Reading (a premorbid IQ estimate) and current overall cognitive abilities into preserved, deteriorated, and compromised groups using both clinical and empirical (k-means clustering) methods. Additional cognitive, functional, and symptom outcomes were compared among the resulting groups. Results: A total of 157 patients (29%) classified as ‘preserved’ performed within one s.d. of control means in all cognitive domains. Patients classified as ‘deteriorated’ (n=239, 44%) performed more than one s.d. below control means in all cognitive domains except estimated premorbid IQ and current visuospatial abilities. A separate 138 patients (26%), classified as ‘compromised,’ performed more than one s.d. below control means in all cognitive domains and displayed greater impairment than other groups on symptom and functional measures. Conclusions: In the present study, we independently replicated our previous cognitive classifications of people with schizophrenia. In addition, we extended previous work by demonstrating worse functional outcomes and symptom severity in the compromised group. PMID:27336046

Impact of Extended-Duration Shifts on Medical Errors, Adverse Events, and Attentional Failures

PubMed Central

Barger, Laura K; Ayas, Najib T; Cade, Brian E; Cronin, John W; Rosner, Bernard; Speizer, Frank E; Czeisler, Charles A

2006-01-01

Background A recent randomized controlled trial in critical-care units revealed that the elimination of extended-duration work shifts (≥24 h) reduces the rates of significant medical errors and polysomnographically recorded attentional failures. This raised the concern that the extended-duration shifts commonly worked by interns may contribute to the risk of medical errors being made, and perhaps to the risk of adverse events more generally. Our current study assessed whether extended-duration shifts worked by interns are associated with significant medical errors, adverse events, and attentional failures in a diverse population of interns across the United States. Methods and Findings We conducted a Web-based survey, across the United States, in which 2,737 residents in their first postgraduate year (interns) completed 17,003 monthly reports. The association between the number of extended-duration shifts worked in the month and the reporting of significant medical errors, preventable adverse events, and attentional failures was assessed using a case-crossover analysis in which each intern acted as his/her own control. Compared to months in which no extended-duration shifts were worked, during months in which between one and four extended-duration shifts and five or more extended-duration shifts were worked, the odds ratios of reporting at least one fatigue-related significant medical error were 3.5 (95% confidence interval [CI], 3.3–3.7) and 7.5 (95% CI, 7.2–7.8), respectively. The respective odds ratios for fatigue-related preventable adverse events, 8.7 (95% CI, 3.4–22) and 7.0 (95% CI, 4.3–11), were also increased. Interns working five or more extended-duration shifts per month reported more attentional failures during lectures, rounds, and clinical activities, including surgery and reported 300% more fatigue-related preventable adverse events resulting in a fatality. Conclusions In our survey, extended-duration work shifts were associated with an increased risk of significant medical errors, adverse events, and attentional failures in interns across the United States. These results have important public policy implications for postgraduate medical education. PMID:17194188

Physiological and emotional responses to subjective social evaluative threat in daily life.

PubMed

Lehman, Barbara J; Cane, Arianna C; Tallon, Shannon J; Smith, Stephanie F

2015-01-01

This study examined concurrent and delayed emotional and cardiovascular correlates of naturally occurring experiences with subjective social evaluative threat (SSET) and tested whether individual differences in social interaction anxiety moderated those associations. Sixty-eight participants wore ambulatory blood pressure monitors for three days. Following each blood pressure reading, participants reported on SSET and negative emotions, yielding 1770 momentary measures. Multilevel modeling suggested that reports of greater SSET uniquely predicted elevations in anxiety and embarrassment, with elevations in anxiety, embarrassment, and shame extending to the hour following SSET. Reports of concurrent and previous-hour SSET also predicted cardiovascular elevations. Linkages between SSET and anxiety and shame, but not cardiovascular measures, were moderated by social interaction anxiety. Those higher in social interaction anxiety showed especially strong associations between SSET and both concurrent and delayed anxiety and greater delayed shame. This research suggests an important role for anxiety, embarrassment, and shame as emotional consequences of naturally occurring evaluative threat, especially for those who are more socially anxious. Further, this work replicates other naturalistic studies that have documented increased blood pressure at times of SSET and extends that work by documenting cardiovascular responses into the following hour.

Meter-Scale 3-D Models of the Martian Surface from Combining MOC and MOLA Data

NASA Technical Reports Server (NTRS)

Soderblom, Laurence A.; Kirk, Randolph L.

2003-01-01

We have extended our previous efforts to derive through controlled photoclinometry, accurate, calibrated, high-resolution topographic models of the martian surface. The process involves combining MGS MOLA topographic profiles and MGS MOC Narrow Angle images. The earlier work utilized, along with a particular MOC NA image, the MOLA topographic profile that was acquired simultaneously, in order to derive photometric and scattering properties of the surface and atmosphere so as to force the low spatial frequencies of a one-dimensional MOC photoclinometric model to match the MOLA profile. Both that work and the new results reported here depend heavily on successful efforts to: 1) refine the radiometric calibration of MOC NA; 2) register the MOC to MOLA coordinate systems and refine the pointing; and 3) provide the ability to project into a common coordinate system, simultaneously acquired MOC and MOLA with a single set of SPICE kernels utilizing the USGS ISIS cartographic image processing tools. The approach described in this paper extends the MOC-MOLA integration and cross-calibration procedures from one-dimensional profiles to full two-dimensional photoclinometry and image simulations. Included are methods to account for low-frequency albedo variations within the scene.

The Gestalt Principle of Similarity Benefits Visual Working Memory

PubMed Central

Peterson, Dwight J.; Berryhill, Marian E.

2013-01-01

Visual working memory (VWM) is essential for many cognitive processes yet it is notably limited in capacity. Visual perception processing is facilitated by Gestalt principles of grouping, such as connectedness, similarity, and proximity. This introduces the question: do these perceptual benefits extend to VWM? If so, can this be an approach to enhance VWM function by optimizing the processing of information? Previous findings demonstrate that several Gestalt principles (connectedness, common region, and spatial proximity) do facilitate VWM performance in change detection tasks (Woodman, Vecera, & Luck, 2003; Xu, 2002a, 2006; Xu & Chun, 2007; Jiang, Olson & Chun, 2000). One prevalent Gestalt principle, similarity, has not been examined with regard to facilitating VWM. Here, we investigated whether grouping by similarity benefits VWM. Experiment 1 established the basic finding that VWM performance could benefit from grouping. Experiment 2 replicated and extended this finding by showing that similarity was only effective when the similar stimuli were proximal. In short, the VWM performance benefit derived from similarity was constrained by spatial proximity such that similar items need to be near each other. Thus, the Gestalt principle of similarity benefits visual perception, but it can provide benefits to VWM as well. PMID:23702981

The Gestalt principle of similarity benefits visual working memory.

PubMed

Peterson, Dwight J; Berryhill, Marian E

2013-12-01

Visual working memory (VWM) is essential for many cognitive processes, yet it is notably limited in capacity. Visual perception processing is facilitated by Gestalt principles of grouping, such as connectedness, similarity, and proximity. This introduces the question, do these perceptual benefits extend to VWM? If so, can this be an approach to enhance VWM function by optimizing the processing of information? Previous findings have demonstrated that several Gestalt principles (connectedness, common region, and spatial proximity) do facilitate VWM performance in change detection tasks (Jiang, Olson, & Chun, 2000; Woodman, Vecera, & Luck, 2003; Xu, 2002, 2006; Xu & Chun, 2007). However, one prevalent Gestalt principle, similarity, has not been examined with regard to facilitating VWM. Here, we investigated whether grouping by similarity benefits VWM. Experiment 1 established the basic finding that VWM performance could benefit from grouping. Experiment 2 replicated and extended this finding by showing that similarity was only effective when the similar stimuli were proximal. In short, the VWM performance benefit derived from similarity was constrained by spatial proximity, such that similar items need to be near each other. Thus, the Gestalt principle of similarity benefits visual perception, but it can provide benefits to VWM as well.

Oxytocin and vasopressin effects on the neural response to social cooperation are modulated by sex in humans.

PubMed

Feng, Chunliang; Hackett, Patrick D; DeMarco, Ashley C; Chen, Xu; Stair, Sabrina; Haroon, Ebrahim; Ditzen, Beate; Pagnoni, Giuseppe; Rilling, James K

2015-12-01

Recent research has examined the effects of oxytocin (OT) and vasopressin (AVP) on human social behavior and brain function. However, most participants have been male, while previous research in our lab demonstrated sexually differentiated effects of OT and AVP on the neural response to reciprocated cooperation. Here we extend our previous work by significantly increasing the number of participants to enable the use of more stringent statistical thresholds that permit more precise localization of OT and AVP effects in the brain. In a double-blind, placebo-controlled study, 153 men and 151 women were randomized to receive 24 IU intranasal OT, 20 IU intranasal AVP or placebo. Afterwards, they were imaged with fMRI while playing an iterated Prisoner's Dilemma Game with same-sex partners. Sex differences were observed for effects of OT on the neural response to reciprocated cooperation, such that OT increased the caduate/putamen response among males, whereas it decreased this response among females. Thus, 24 IU OT may increase the reward or salience of positive social interactions among men, while decreasing their reward or salience among women. Similar sex differences were also observed for AVP effects within bilateral insula and right supramarginal gyrus when a more liberal statistical threshold was employed. While our findings support previous suggestions that exogenous nonapeptides may be effective treatments for disorders such as depression and autism spectrum disorder, they caution against uniformly extending such treatments to men and women alike.

Caring for the Elderly at Work and Home: Can a Randomized Organizational Intervention Improve Psychological Health?

PubMed

Kossek, Ellen Ernst; Thompson, Rebecca J; Lawson, Katie M; Bodner, Todd; Perrigino, Matthew B; Hammer, Leslie B; Buxton, Orfeu M; Almeida, David M; Moen, Phyllis; Hurtado, David A; Wipfli, Brad; Berkman, Lisa F; Bray, Jeremy W

2017-12-07

Although job stress models suggest that changing the work social environment to increase job resources improves psychological health, many intervention studies have weak designs and overlook influences of family caregiving demands. We tested the effects of an organizational intervention designed to increase supervisor social support for work and nonwork roles, and job control in a results-oriented work environment on the stress and psychological distress of health care employees who care for the elderly, while simultaneously considering their own family caregiving responsibilities. Using a group-randomized organizational field trial with an intent-to-treat design, 420 caregivers in 15 intervention extended-care nursing facilities were compared with 511 caregivers in 15 control facilities at 4 measurement times: preintervention and 6, 12, and 18 months. There were no main intervention effects showing improvements in stress and psychological distress when comparing intervention with control sites. Moderation analyses indicate that the intervention was more effective in reducing stress and psychological distress for caregivers who were also caring for other family members off the job (those with elders and those "sandwiched" with both child and elder caregiving responsibilities) compared with employees without caregiving demands. These findings extend previous studies by showing that the effect of organizational interventions designed to increase job resources to improve psychological health varies according to differences in nonwork caregiving demands. This research suggests that caregivers, especially those with "double-duty" elder caregiving at home and work and "triple-duty" responsibilities, including child care, may benefit from interventions designed to increase work-nonwork social support and job control. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Supercritical wing sections 2, volume 108

NASA Technical Reports Server (NTRS)

Bauer, F.; Garabedian, P.; Korn, D.; Jameson, A.; Beckmann, M. (Editor); Kuenzi, H. P. (Editor)

1975-01-01

A mathematical theory for the design and analysis of supercritical wing sections was previously presented. Examples and computer programs showing how this method works were included. The work on transonics is presented in a more definitive form. For design, a better model of the trailing edge is introduced which should eliminate a loss of fifteen or twenty percent in lift experienced with previous heavily aft loaded models, which is attributed to boundary layer separation. How drag creep can be reduced at off-design conditions is indicated. A rotated finite difference scheme is presented that enables the application of Murman's method of analysis in more or less arbitrary curvilinear coordinate systems. This allows the use of supersonic as well as subsonic free stream Mach numbers and to capture shock waves as far back on an airfoil as desired. Moreover, it leads to an effective three dimensional program for the computation of transonic flow past an oblique wing. In the case of two dimensional flow, the method is extended to take into account the displacement thickness computed by a semi-empirical turbulent boundary layer correction.

Periodic boundary conditions for QM/MM calculations: Ewald summation for extended Gaussian basis sets

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

Holden, Zachary C.; Richard, Ryan M.; Herbert, John M., E-mail: herbert@chemistry.ohio-state.edu

2013-12-28

An implementation of Ewald summation for use in mixed quantum mechanics/molecular mechanics (QM/MM) calculations is presented, which builds upon previous work by others that was limited to semi-empirical electronic structure for the QM region. Unlike previous work, our implementation describes the wave function's periodic images using “ChElPG” atomic charges, which are determined by fitting to the QM electrostatic potential evaluated on a real-space grid. This implementation is stable even for large Gaussian basis sets with diffuse exponents, and is thus appropriate when the QM region is described by a correlated wave function. Derivatives of the ChElPG charges with respect tomore » the QM density matrix are a potentially serious bottleneck in this approach, so we introduce a ChElPG algorithm based on atom-centered Lebedev grids. The ChElPG charges thus obtained exhibit good rotational invariance even for sparse grids, enabling significant cost savings. Detailed analysis of the optimal choice of user-selected Ewald parameters, as well as timing breakdowns, is presented.« less

Spike-Timing Dependent Plasticity in Unipolar Silicon Oxide RRAM Devices

PubMed Central

Zarudnyi, Konstantin; Mehonic, Adnan; Montesi, Luca; Buckwell, Mark; Hudziak, Stephen; Kenyon, Anthony J.

2018-01-01

Resistance switching, or Resistive RAM (RRAM) devices show considerable potential for application in hardware spiking neural networks (neuro-inspired computing) by mimicking some of the behavior of biological synapses, and hence enabling non-von Neumann computer architectures. Spike-timing dependent plasticity (STDP) is one such behavior, and one example of several classes of plasticity that are being examined with the aim of finding suitable algorithms for application in many computing tasks such as coincidence detection, classification and image recognition. In previous work we have demonstrated that the neuromorphic capabilities of silicon-rich silicon oxide (SiOx) resistance switching devices extend beyond plasticity to include thresholding, spiking, and integration. We previously demonstrated such behaviors in devices operated in the unipolar mode, opening up the question of whether we could add plasticity to the list of features exhibited by our devices. Here we demonstrate clear STDP in unipolar devices. Significantly, we show that the response of our devices is broadly similar to that of biological synapses. This work further reinforces the potential of simple two-terminal RRAM devices to mimic neuronal functionality in hardware spiking neural networks. PMID:29472837

Towards an Entropy Stable Spectral Element Framework for Computational Fluid Dynamics

NASA Technical Reports Server (NTRS)

Carpenter, Mark H.; Parsani, Matteo; Fisher, Travis C.; Nielsen, Eric J.

2016-01-01

Entropy stable (SS) discontinuous spectral collocation formulations of any order are developed for the compressible Navier-Stokes equations on hexahedral elements. Recent progress on two complementary efforts is presented. The first effort is a generalization of previous SS spectral collocation work to extend the applicable set of points from tensor product, Legendre-Gauss-Lobatto (LGL) to tensor product Legendre-Gauss (LG) points. The LG and LGL point formulations are compared on a series of test problems. Although being more costly to implement, it is shown that the LG operators are significantly more accurate on comparable grids. Both the LGL and LG operators are of comparable efficiency and robustness, as is demonstrated using test problems for which conventional FEM techniques suffer instability. The second effort generalizes previous SS work to include the possibility of p-refinement at non-conforming interfaces. A generalization of existing entropy stability machinery is developed to accommodate the nuances of fully multi-dimensional summation-by-parts (SBP) operators. The entropy stability of the compressible Euler equations on non-conforming interfaces is demonstrated using the newly developed LG operators and multi-dimensional interface interpolation operators.

Postural response to predictable and nonpredictable visual flow in children and adults.

PubMed

Schmuckler, Mark A

2017-11-01

Children's (3-5years) and adults' postural reactions to different conditions of visual flow information varying in its frequency content was examined using a moving room apparatus. Both groups experienced four conditions of visual input: low-frequency (0.20Hz) visual oscillations, high-frequency (0.60Hz) oscillations, multifrequency nonpredictable visual input, and no imposed visual information. Analyses of the frequency content of anterior-posterior (AP) sway revealed that postural reactions to the single-frequency conditions replicated previous findings; children were responsive to low- and high-frequency oscillations, whereas adults were responsive to low-frequency information. Extending previous work, AP sway in response to the nonpredictable condition revealed that both groups were responsive to the different components contained in the multifrequency visual information, although adults retained their frequency selectivity to low-frequency versus high-frequency content. These findings are discussed in relation to work examining feedback versus feedforward control of posture, and the reweighting of sensory inputs for postural control, as a function of development and task context. Copyright © 2017 Elsevier Inc. All rights reserved.

Risk factors for colonization with extended-spectrum beta-lactamase producing Enterobacteriaceae in healthcare students on clinical assignment abroad: A prospective study.

PubMed

Angelin, Martin; Forsell, Joakim; Granlund, Margareta; Evengård, Birgitta; Palmgren, Helena; Johansson, Anders

2015-01-01

The increase of antibiotic resistance in clinically important bacteria is a worldwide threat, especially in healthcare environments. International travel is a risk factor for gut colonization with extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). The risk for healthcare students of being colonized with ESBL-PE when participating in patient-related work abroad has not been previously investigated. Swedish healthcare students travelling for pre-clinical and clinical courses outside Scandinavia submitted faecal samples and survey data before and after travel. The faecal samples were screened for ESBL-PE and carbapenemase-producing Enterobacteriaceae (CPE). Screening results and survey data were analysed to identify risk factors for colonization. In the 99 subjects who submitted a full set of samples, 35% were colonized with a new ESBL-PE strain during travel. No CPE was found. The most important risk factor for ESBL-PE colonization was travel destination, and the highest colonization rate was found in the South-East Asia region. Antibiotic treatment during travel was an independent risk factor for ESBL-PE colonization but patient-related work was not significantly associated with an increased risk. Patient-related work abroad was not a risk factor for ESBL-PE suggesting that transmission from patients is uncommon. Pre-travel advice on avoiding unnecessary antibiotic treatment during travel is recommended. Copyright © 2015 Elsevier Ltd. All rights reserved.

Walking on ballast impacts balance.

PubMed

Wade, Chip; Garner, John C; Redfern, Mark S; Andres, Robert O

2014-01-01

Railroad workers often perform daily work activities on irregular surfaces, specifically on ballast rock. Previous research and injury epidemiology have suggested a relationship between working on irregular surfaces and postural instability. The purpose of this study was to examine the impact of walking on ballast for an extended duration on standing balance. A total of 16 healthy adult males walked on a 7.62 m × 4.57 m (25 ft × 15 ft) walking surface of no ballast (NB) or covered with ballast (B) of an average rock size of about 1 inch for 4 h. Balance was evaluated using dynamic posturography with the NeuroCom(®) Equitest System(™) prior to experiencing the NB or B surface and again every 30 min during the 4 h of ballast exposure. Dependent variables were the sway velocity and root-mean-square (RMS) sway components in the medial-lateral and anterior-posterior directions. Repeated measures ANOVA revealed statistically significant differences in RMS and sway velocity between ballast surface conditions and across exposure times. Overall, the ballast surface condition induced greater sway in all of the dynamic posturography conditions. Walking on irregular surfaces for extended durations has a deleterious effect on balance compared to walking on a surface without ballast. These findings of changes in balance during ballast exposure suggest that working on an irregular surface may impact postural control.

Beyond parenting practices: extended kinship support and the academic adjustment of African-American and European-American teens.

PubMed

Pallock, Linda L; Lamborn, Susie D

2006-10-01

This study examined adolescents' perceptions of parenting practices and extended kinship support in relation to academic adjustment for 104 African American and 60 European American 9th and 10th graders (14 and 15 year olds). For African-American teens, parental acceptance was associated with school values, teacher bonding, and work orientation. Higher levels of behavioral control and lower levels of psychological control were associated with a stronger work orientation. After accounting for the demographic variables and the three parenting practices, higher levels of extended kinship support related to stronger school values, higher teacher bonding, and a stronger work orientation. For European-American teens, parental acceptance related to academic adjustment, including stronger school values, higher teacher bonding, and a stronger work orientation. European-American adolescents with stronger extended kinship networks reported higher teacher bonding and a stronger work orientation. Results indicate the importance of extended kinship support for both African-American and European-American adolescents.

Number word use in toddlerhood is associated with number recall performance at seven years of age.

PubMed

Libertus, Melissa E; Marschik, Peter B; Einspieler, Christa

2014-01-01

Previous studies have shown that verbal working memory and vocabulary acquisition are linked in early childhood. However, it is unclear whether acquisition of a narrow range of words during toddlerhood may be particularly related to recall of the same words later in life. Here we asked whether vocabulary acquisition of number words, location and quantifier terms over the first three years of life are associated with verbal and visuospatial working memory at seven years. Our results demonstrate that children who produced more number words between 20-26 months and started to produce the number words 1-10 earlier showed greater number recall at 7 years of age. This link was specific to numbers and neither extended to quantifier and location terms nor verbal and visuospatial working memory performance with other stimuli. These findings suggest a category-specific link between the mental lexicon of number words and working memory for numbers at an early age.

Safety behavior: Job demands, job resources, and perceived management commitment to safety.

PubMed

Hansez, Isabelle; Chmiel, Nik

2010-07-01

The job demands-resources model posits that job demands and resources influence outcomes through job strain and work engagement processes. We test whether the model can be extended to effort-related "routine" safety violations and "situational" safety violations provoked by the organization. In addition we test more directly the involvement of job strain than previous studies which have used burnout measures. Structural equation modeling provided, for the first time, evidence of predicted relationships between job strain and "routine" violations and work engagement with "routine" and "situational" violations, thereby supporting the extension of the job demands-resources model to safety behaviors. In addition our results showed that a key safety-specific construct 'perceived management commitment to safety' added to the explanatory power of the job demands-resources model. A predicted path from job resources to perceived management commitment to safety was highly significant, supporting the view that job resources can influence safety behavior through both general motivational involvement in work (work engagement) and through safety-specific processes.

Development and initial evaluation of an enhanced measure of boundary flexibility for the work and family domains.

PubMed

Matthews, Russell A; Barnes-Farrell, Janet L

2010-07-01

This manuscript reports the development of a measure of work and family domain boundary flexibility. Building on previous research, we propose an expanded definition of boundary flexibility that includes two components-flexibility-ability and flexibility-willingness-and we develop a measure designed to capture this more comprehensive definition of boundary flexibility. Flexibility-ability is conceptualized as an individual's perception of personal and situational constraints that affect boundary management, and flexibility-willingness is conceptualized as an individual difference variable that captures the motivation to engage in boundary flexing. An additional feature of domain boundaries, permeability, is also examined. Data are presented from two studies. Study 1 (N = 244) describes the development of a multiscale measure that extends current conceptual definitions of boundary flexibility. Study 2 (N = 225) describes the refinement and evaluation of this measure. Confirmatory factor analysis, reliability evidence, interscale correlations, and correlations with important work-family constructs (e.g., domain centrality, work-family conflict) provide initial construct validity evidence for the measure.

Context-specific attentional sampling: Intentional control as a pre-requisite for contextual control.

PubMed

Brosowsky, Nicholaus P; Crump, Matthew J C

2016-08-01

Recent work suggests that environmental cues associated with previous attentional control settings can rapidly and involuntarily adjust attentional priorities. The current study tests predictions from adaptive-learning and memory-based theories of contextual control about the role of intentions for setting attentional priorities. To extend the empirical boundaries of contextual control phenomena, and to determine whether theoretical principles of contextual control are generalizable we used a novel bi-dimensional stimulus sampling task. Subjects viewed briefly presented arrays of letters and colors presented above or below fixation, and identified specific stimuli according to a dimensional (letter or color) and positional cue. Location was predictive of the cued dimension, but not the position or identity. In contrast to previous findings, contextual control failed to develop through automatic, adaptive-learning processes. Instead, previous experience with intentionally changing attentional sampling priorities between different contexts was required for contextual control to develop. Copyright © 2016 Elsevier Inc. All rights reserved.

Cultural variation in implicit independence: An extension of Kitayama et al. ().

PubMed

Park, Jiyoung; Uchida, Yukiko; Kitayama, Shinobu

2016-08-01

Previous research shows that European Americans are consistently more independent (or less interdependent) than Japanese when implicit indices are used to assess independence (vs. interdependence). The present work extended this evidence by including a novel implicit association test (IAT), as an index of implicit attitude towards independence and interdependence. Consistent with the previous findings, as compared to Japanese, Americans were significantly higher in multiple indices of implicit independence (vs. interdependence) including personal (vs. social) self-definition, experience of disengaging (vs. engaging) emotions and personal (vs. social) form of happiness. Furthermore, as compared to Japanese, Americans had a significantly more positive implicit attitude towards independence assessed with the IAT. As also observed in the previous research, explicit measures showed inconsistent cross-cultural patterns. Lastly, we observed little statistical within-culture coherence among the implicit measures of independence (vs. interdependence), consistent with a view that the implicit indices capture alternative ways for individuals to achieve the cultural mandate of independence or interdependence. © 2015 International Union of Psychological Science.

Cardiovascular reactions to psychological stress and abuse history: the role of occurrence, frequency, and type of abuse.

PubMed

Ginty, Annie T; Masters, Nicole A; Nelson, Eliza B; Kaye, Karen T; Conklin, Sarah M

2017-03-01

Extreme cardiovascular reactions to psychological stress have been associated with traumatic life experiences. Previous studies have focused on the occurrence or frequency of abuse rather than type of abuse. We examined how occurrence, frequency, and the type of abuse history are related to cardiovascular reactivity (CVR) to acute psychological stress. The study consisted of between group and continuous analyses to examine the association between occurrence, type, and frequency of abuse with cardiovascular reactions to acute psychological stress. Data from 64 participants were collected. Heart rate, systolic blood pressure, and diastolic blood pressure were measured at baseline and during a standard mental arithmetic stress task. Individuals who experienced abuse showed diminished CVR to acute psychological stress; this was driven specifically by the history of sexual abuse. Frequency of abuse did not relate to stress reactions. These findings accord with previous work suggesting a relationship between traumatic life experience and hypoarousal in physiological reactivity and extend previous findings by suggesting the relationship may be driven by sexual abuse.

Colour assortative pairing in a colour polymorphic lizard is independent of population morph diversity

NASA Astrophysics Data System (ADS)

Pérez i de Lanuza, Guillem; Font, Enrique; Carretero, Miguel Ángel

2016-10-01

Previous work with a colour polymorphic population of Podarcis muralis (Lacertidae) revealed that lizards pair by ventral colour, favouring the same colour (i.e. homomorphic) pairs. Such assortative pairing, which probably results in colour assortative mating, can have consequences for the genetic structure of the population and potentially promote speciation. The population previously studied, located in the Pyrenees, encompasses white, yellow and orange animals, as well as intermediate white-orange and yellow-orange morphs. However, other Pyrenean populations of P. muralis have less ventral colour morphs. Our aim in this study is to test the generality of the assortative colour pairing system, extending our previous analyses to populations with different morph compositions and frequencies. The results show that the assortative pattern of pairing is similar in all the populations analysed and, hence, independent of morph composition and not restricted to pentamorphic populations. This suggests that assortative pairing by colour is a general phenomenon for colour polymorphic populations of P. muralis.

The effect of anisotropic heat transport on magnetic islands in 3-D configurations

NASA Astrophysics Data System (ADS)

Schlutt, M. G.; Hegna, C. C.

2012-08-01

An analytic theory of nonlinear pressure-induced magnetic island formation using a boundary layer analysis is presented. This theory extends previous work by including the effects of finite parallel heat transport and is applicable to general three dimensional magnetic configurations. In this work, particular attention is paid to the role of finite parallel heat conduction in the context of pressure-induced island physics. It is found that localized currents that require self-consistent deformation of the pressure profile, such as resistive interchange and bootstrap currents, are attenuated by finite parallel heat conduction when the magnetic islands are sufficiently small. However, these anisotropic effects do not change saturated island widths caused by Pfirsch-Schlüter current effects. Implications for finite pressure-induced island healing are discussed.

Simple neural substrate predicts complex rhythmic structure in duetting birds

NASA Astrophysics Data System (ADS)

Amador, Ana; Trevisan, M. A.; Mindlin, G. B.

2005-09-01

Horneros (Furnarius Rufus) are South American birds well known for their oven-looking nests and their ability to sing in couples. Previous work has analyzed the rhythmic organization of the duets, unveiling a mathematical structure behind the songs. In this work we analyze in detail an extended database of duets. The rhythms of the songs are compatible with the dynamics presented by a wide class of dynamical systems: forced excitable systems. Compatible with this nonlinear rule, we build a biologically inspired model for how the neural and the anatomical elements may interact to produce the observed rhythmic patterns. This model allows us to synthesize songs presenting the acoustic and rhythmic features observed in real songs. We also make testable predictions in order to support our hypothesis.

Relativistic algorithm for time transfer in Mars missions under IAU Resolutions: an analytic approach

NASA Astrophysics Data System (ADS)

Pan, Jun-Yang; Xie, Yi

2015-02-01

With tremendous advances in modern techniques, Einstein's general relativity has become an inevitable part of deep space missions. We investigate the relativistic algorithm for time transfer between the proper time τ of the onboard clock and the Geocentric Coordinate Time, which extends some previous works by including the effects of propagation of electromagnetic signals. In order to evaluate the implicit algebraic equations and integrals in the model, we take an analytic approach to work out their approximate values. This analytic model might be used in an onboard computer because of its limited capability to perform calculations. Taking an orbiter like Yinghuo-1 as an example, we find that the contributions of the Sun, the ground station and the spacecraft dominate the outcomes of the relativistic corrections to the model.

The Longue Durée of Black Lives Matter.

PubMed

Nelson, Alondra

2016-10-01

Black Lives Matter was first articulated just a few years ago, but it has been the leitmotif of antiracist struggles for generations. The Movement for Black Lives extends the work of previous movements that challenged forms of oppression that act on Black bodies with impunity. It should be understood in the context of Ida B. Wells' anti-lynching campaign, Fannie Lou Hamer's reproductive justice demands, and the Black Panther Party's health activism. The 50th anniversary of the Black Panther Party is an occasion to recall that its work confronted the callous neglect and the corporeal surveillance and abuse of poor Black communities. Similar demands have been the centrifugal force of social movements that for centuries have refused to have Black lives cast beyond the human boundary.

Anxiety Sensitivity as a Mediator of the Relationship between Moderate-Intensity Exercise and Coping-Oriented Marijuana Use Motives

PubMed Central

Smits, Jasper A. J.; Bonn-Miller, Marcel O.; Tart, Candyce D.; Irons, Jessica G.; Zvolensky, Michael J.

2011-01-01

The present study examined the working hypothesis that moderate-intensity exercise is associated with coping-oriented marijuana use motives through its association with the fear of somatic arousal (i.e., anxiety sensitivity). Using data from 146 young adult current marijuana users we found evidence consistent with this hypothesis. Specifically, moderate-intensity exercise was associated with coping-oriented use motives, even after controlling for frequency of current marijuana use and other co-occurring marijuana use motives. This relationship became non-significant after entering anxiety sensitivity as an additional predictor variable, denoting a putative mediational role for this cognitve factor. These findings extend previous work and offer support for the potential utility of moderate-intensity aerobic exercise for the treatment of marijuana use problems. PMID:21314753

The Longue Durée of Black Lives Matter

PubMed Central

2016-01-01

Black Lives Matter was first articulated just a few years ago, but it has been the leitmotif of antiracist struggles for generations. The Movement for Black Lives extends the work of previous movements that challenged forms of oppression that act on Black bodies with impunity. It should be understood in the context of Ida B. Wells’ anti-lynching campaign, Fannie Lou Hamer’s reproductive justice demands, and the Black Panther Party’s health activism. The 50th anniversary of the Black Panther Party is an occasion to recall that its work confronted the callous neglect and the corporeal surveillance and abuse of poor Black communities. Similar demands have been the centrifugal force of social movements that for centuries have refused to have Black lives cast beyond the human boundary. PMID:27626337

Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

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

Aab, A.; Abreu, P.; Aglietta, M.

We present a new method for probing the hadronic interaction models at ultra-high energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air-showers. Using the risetimes of the recorded signals we define a new parameter, which we use to compare our observations with predictions from simulations. We find, firstly, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies.more » Secondly, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum for a sample of over 81,000 events extending from 0.3 EeV to over 100 EeV. Above 30 EeV, the sample is nearly fourteen times larger than currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of the average depth of shower maximum is compared to simulations and interpreted in terms of the mean of the logarithmic mass. Here, we find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.« less

Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

DOE PAGES

Aab, A.; Abreu, P.; Aglietta, M.; ...

2017-12-08

We present a new method for probing the hadronic interaction models at ultra-high energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air-showers. Using the risetimes of the recorded signals we define a new parameter, which we use to compare our observations with predictions from simulations. We find, firstly, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies.more » Secondly, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum for a sample of over 81,000 events extending from 0.3 EeV to over 100 EeV. Above 30 EeV, the sample is nearly fourteen times larger than currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of the average depth of shower maximum is compared to simulations and interpreted in terms of the mean of the logarithmic mass. Here, we find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.« less

Modeling wormholes in f (R ,T ) gravity

NASA Astrophysics Data System (ADS)

Moraes, P. H. R. S.; Sahoo, P. K.

2017-08-01

In this work, we propose the modeling of static wormholes within the f (R ,T ) extended theory of gravity perspective. We present some models of wormholes, which are constructed from different hypotheses for their matter content, i.e., different relations for their pressure components (radial and lateral) and different equations of state. The solutions obtained for the shape function of the wormholes obey the necessary metric conditions. They show a behavior similar to those found in previous references about wormholes, which also happens to our solutions for the energy density of such objects. We also apply the energy conditions for the wormholes' physical content.

Some features of Australian exhibitionists compared with pedophiles.

PubMed

Myers, R G; Berah, E F

1983-12-01

In an attempt to extend the findings of previous research and to investigate the hypothesis of a link between exhibitionism and pedophilia, samples of Australian offenders undergoing presentence psychiatric assessment were compared on a number of variables. The data suggested that the exhibitionists and pedophiles in the sample represented different populations: the exhibitionists were younger, tended to come from more stable and harmonious families, and had superior school and work records. The common assumption of disinhibition as a feature of exhibitionism was questioned on the basis of the finding that almost no exhibitionists were intoxicated at the time of their offense.

A Framework for Evaluating and Enhancing Alignment in Self-Regulated Learning Research

PubMed Central

Dent, Amy L.; Hoyle, Rick H.

2015-01-01

We discuss the articles of this special issue with reference to an important yet previously only implicit dimension of study quality: alignment across the theoretical and methodological decisions that collectively define an approach to self-regulated learning. Integrating and extending work by leaders in the field, we propose a framework for evaluating alignment in the way self-regulated learning research is both conducted and reported. Within this framework, the special issue articles provide a springboard for discussing methodological promises and pitfalls of increasingly sophisticated research on the dynamic, contingent, and contextualized features of self-regulated learning. PMID:25825589

Compression of real time volumetric echocardiographic data using modified SPIHT based on the three-dimensional wavelet packet transform.

PubMed

Hang, X; Greenberg, N L; Shiota, T; Firstenberg, M S; Thomas, J D

2000-01-01

Real-time three-dimensional echocardiography has been introduced to provide improved quantification and description of cardiac function. Data compression is desired to allow efficient storage and improve data transmission. Previous work has suggested improved results utilizing wavelet transforms in the compression of medical data including 2D echocardiogram. Set partitioning in hierarchical trees (SPIHT) was extended to compress volumetric echocardiographic data by modifying the algorithm based on the three-dimensional wavelet packet transform. A compression ratio of at least 40:1 resulted in preserved image quality.

Finite-time synchronization control of a class of memristor-based recurrent neural networks.

PubMed

Jiang, Minghui; Wang, Shuangtao; Mei, Jun; Shen, Yanjun

2015-03-01

This paper presents a global and local finite-time synchronization control law for memristor neural networks. By utilizing the drive-response concept, differential inclusions theory, and Lyapunov functional method, we establish several sufficient conditions for finite-time synchronization between the master and corresponding slave memristor-based neural network with the designed controller. In comparison with the existing results, the proposed stability conditions are new, and the obtained results extend some previous works on conventional recurrent neural networks. Two numerical examples are provided to illustrate the effective of the design method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Unified formalism for higher order non-autonomous dynamical systems

NASA Astrophysics Data System (ADS)

Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso

2012-03-01

This work is devoted to giving a geometric framework for describing higher order non-autonomous mechanical systems. The starting point is to extend the Lagrangian-Hamiltonian unified formalism of Skinner and Rusk for these kinds of systems, generalizing previous developments for higher order autonomous mechanical systems and first-order non-autonomous mechanical systems. Then, we use this unified formulation to derive the standard Lagrangian and Hamiltonian formalisms, including the Legendre-Ostrogradsky map and the Euler-Lagrange and the Hamilton equations, both for regular and singular systems. As applications of our model, two examples of regular and singular physical systems are studied.

Concerto catalysis--harmonising [NiFe]hydrogenase and NiRu model catalysts.

PubMed

Ichikawa, Koji; Nonaka, Kyoshiro; Matsumoto, Takahiro; Kure, Bunsho; Yoon, Ki-Seok; Higuchi, Yoshiki; Yagi, Tatsuhiko; Ogo, Seiji

2010-03-28

This communication reports the successful merging of the chemical properties of a natural [NiFe]hydrogenase (Desulfovibrio vulgaris Miyazaki F) and our previously reported [NiRu] hydrogenase-mimic. The catalytic activity of both the natural enzyme and the mimic is almost identical, with the exception of working pH ranges, and this allows us to use them simultaneously in the same reaction flask. In such a manner, isotope exchange between D(2) and H(2)O could be conducted over an extended pH range (about 2-10) in one pot under mild conditions at ambient temperature and pressure.

Toward a generalized theory of epidemic awareness in social networks

NASA Astrophysics Data System (ADS)

Wu, Qingchu; Zhu, Wenfang

We discuss the dynamics of a susceptible-infected-susceptible (SIS) model with local awareness in networks. Individual awareness to the infectious disease is characterized by a general function of epidemic information in its neighborhood. We build a high-accuracy approximate equation governing the spreading dynamics and derive an approximate epidemic threshold above which the epidemic spreads over the whole network. Our results extend the previous work and show that the epidemic threshold is dependent on the awareness function in terms of one infectious neighbor. Interestingly, when a pow-law awareness function is chosen, the epidemic threshold can emerge in infinite networks.

Distinguishing computable mixtures of quantum states

NASA Astrophysics Data System (ADS)

Grande, Ignacio H. López; Senno, Gabriel; de la Torre, Gonzalo; Larotonda, Miguel A.; Bendersky, Ariel; Figueira, Santiago; Acín, Antonio

2018-05-01

In this article we extend results from our previous work [Bendersky et al., Phys. Rev. Lett. 116, 230402 (2016), 10.1103/PhysRevLett.116.230402] by providing a protocol to distinguish in finite time and with arbitrarily high success probability any algorithmic mixture of pure states from the maximally mixed state. Moreover, we include an experimental realization, using a modified quantum key distribution setup, where two different random sequences of pure states are prepared; these sequences are indistinguishable according to quantum mechanics, but they become distinguishable when randomness is replaced with pseudorandomness within the experimental preparation process.

Asynchronous discrete control of continuous processes

NASA Astrophysics Data System (ADS)

Kaliski, M. E.; Johnson, T. L.

1984-07-01

The research during this second contract year continued to deal with the development of sound theoretical models for asynchronous systems. Two criteria served to shape the research pursued: the first, that the developed models extend and generalize previously developed research for synchronous discrete control; the second, that the models explicitly address the question of how to incorporate system transition times into themselves. The following sections of this report concisely delineate this year's work. Our original proposal for this research identified four general tasks of investigation: (1.1) Analysis of Qualitative Properties of Asynchronous Hybrid Systems; (1.2) Acceptance and Control for Asynchronous Hybrid Systems.

Pitot pressure analyses in CO2 condensing rarefied hypersonic flows

NASA Astrophysics Data System (ADS)

Ozawa, T.; Suzuki, T.; Fujita, K.

2016-11-01

In order to improve the accuracy of rarefied aerodynamic prediction, a hypersonic rarefied wind tunnel (HRWT) was developed at Japan Aerospace Exploration Agency. While this wind tunnel has been limited to inert gases, such as nitrogen or argon, we recently extended the capability of HRWT to CO2 hypersonic flows for several Mars missions. Compared to our previous N2 cases, the condensation effect may not be negligible for CO2 rarefied aerodynamic measurements. Thus, in this work, we have utilized both experimental and numerical approaches to investigate the condensation and rarefaction effects in CO2 hypersonic nozzle flows.

Fabrication Materials for a Closed Cycle Brayton Turbine Wheel

NASA Technical Reports Server (NTRS)

Khandelwal, Suresh; Hah, Chunill; Powers, Lynn M.; Stewart, Mark E.; Suresh, Ambady; Owen, Albert K.

2006-01-01

A multidisciplinary analysis of a radial inflow turbine rotor is presented. This work couples high-fidelity fluid, structural, and thermal simulations in a seamless multidisciplinary analysis to investigate the consequences of material selection. This analysis extends multidisciplinary techniques previously demonstrated on rocket turbopumps and hypersonic engines. Since no design information is available for the anticipated Brayton rotating machinery, an existing rotor design (the Brayton Rotating Unit (BRU)) was used in the analysis. Steady state analysis results of a notional turbine rotor indicate that stress levels are easily manageable at the turbine inlet temperature, and stress levels anticipated using either superalloys or ceramics.

How many photons are needed to reconstruct random objects in coherent X-ray diffractive imaging?

PubMed

Jahn, T; Wilke, R N; Chushkin, Y; Salditt, T

2017-01-01

This paper presents an investigation of the reconstructibility of coherent X-ray diffractive imaging diffraction patterns for a class of binary random `bitmap' objects. Combining analytical results and numerical simulations, the critical fluence per bitmap pixel is determined, for arbitrary contrast values (absorption level and phase shift), both for the optical near- and far-field. This work extends previous investigations based on information theory, enabling a comparison of the amount of information carried by single photons in different diffraction regimes. The experimental results show an order-of-magnitude agreement.

Outcomes from the Mount Sinai Social Work Leadership Enhancement Program: Evaluation and extrapolation.

PubMed

Nilsson, David; Wellington-Boyd, Anna

2006-01-01

This article presents an overview of outcomes from the Mount Sinai Leadership Enhancement Program as identified by previous program participants from Melbourne, Australia. These are categorised into: (1) Personal/professional, (2) Intra-organisational, (3) Interorganisational, and (4) International outcomes. Two illustrative examples are provided of international outcomes demonstrating how the ongoing commitment of Professor Epstein has extended and embedded the principles of practice-based research in Melbourne, and how the over-riding principles of the program have been applied by participants in establishing collaborative relationships with colleagues in our neighbouring South-East Asian region.

Designing teams of unattended ground sensors using genetic algorithms

NASA Astrophysics Data System (ADS)

Yilmaz, Ayse S.; McQuay, Brian N.; Wu, Annie S.; Sciortino, John C., Jr.

2004-04-01

Improvements in sensor capabilities have driven the need for automated sensor allocation and management systems. Such systems provide a penalty-free test environment and valuable input to human operators by offering candidate solutions. These abilities lead, in turn, to savings in manpower and time. Determining an optimal team of cooperating sensors for military operations is a challenging task. There is a tradeoff between the desire to decrease the cost and the need to increase the sensing capabilities of a sensor suite. This work focuses on unattended ground sensor networks consisting of teams of small, inexpensive sensors. Given a possible configuration of enemy radar, our goal isto generate sensor suites that monitor as many enemy radar as possible while minimizing cost. In previous work, we have shown that genetic algorithms (GAs) can be used to evolve successful teams of sensors for this problem. This work extends our previous work in two ways: we use an improved simulator containing a more accurate model of radar and sensor capabilities for out fitness evaluations and we introduce two new genetic operators, insertion and deletion, that are expected to improve the GA's fine tuning abilities. Empirical results show that our GA approach produces near optimal results under a variety of enemy radar configurations using sensors with varying capabilities. Detection percentage remains stable regardless of changes in the enemy radar placements.

A multiscale strength model for tantalum over an extended range of strain rates

NASA Astrophysics Data System (ADS)

Barton, N. R.; Rhee, M.

2013-09-01

A strength model for tantalum is developed and exercised across a range of conditions relevant to various types of experimental observations. The model is based on previous multiscale modeling work combined with experimental observations. As such, the model's parameterization includes a hybrid of quantities that arise directly from predictive sub-scale physics models and quantities that are adjusted to align the model with experimental observations. Given current computing and experimental limitations, the response regions for sub-scale physics simulations and detailed experimental observations have been largely disjoint. In formulating the new model and presenting results here, attention is paid to integrated experimental observations that probe strength response at the elevated strain rates where a previous version of the model has generally been successful in predicting experimental data [Barton et al., J. Appl. Phys. 109(7), 073501 (2011)].

Probing sub-GeV dark matter-baryon scattering with cosmological observables

NASA Astrophysics Data System (ADS)

Xu, Weishuang Linda; Dvorkin, Cora; Chael, Andrew

2018-05-01

We derive new limits on the elastic scattering cross section between baryons and dark matter using cosmic microwave background data from the Planck satellite and measurements of the Lyman-alpha forest flux power spectrum from the Sloan Digital Sky Survey. Our analysis addresses generic cross sections of the form σ ∝vn , where v is the dark matter-baryon relative velocity, allowing for constraints on the cross section independent of specific particle physics models. We include high-ℓ polarization data from Planck in our analysis, improving over previous constraints. We apply a more careful treatment of dark matter thermal evolution than previously done, allowing us to extend our constraints down to dark matter masses of ˜MeV . We show in this work that cosmological probes are complementary to current direct detection and astrophysical searches.

Bethe-Boltzmann hydrodynamics and spin transport in the XXZ chain

NASA Astrophysics Data System (ADS)

Bulchandani, Vir B.; Vasseur, Romain; Karrasch, Christoph; Moore, Joel E.

2018-01-01

Quantum integrable systems, such as the interacting Bose gas in one dimension and the XXZ quantum spin chain, have an extensive number of local conserved quantities that endow them with exotic thermalization and transport properties. We discuss recently introduced hydrodynamic approaches for such integrable systems from the viewpoint of kinetic theory and extend the previous works by proposing a numerical scheme to solve the hydrodynamic equations for finite times and arbitrary locally equilibrated initial conditions. We then discuss how such methods can be applied to describe nonequilibrium steady states involving ballistic heat and spin currents. In particular, we show that the spin Drude weight in the XXZ chain, previously accessible only by rigorous techniques of limited scope or controversial thermodynamic Bethe ansatz arguments, may be evaluated from hydrodynamics in very good agreement with density-matrix renormalization group calculations.

Unimpaired perception of social and physical causality, but impaired perception of animacy in high functioning children with autism.

PubMed

Congiu, Sara; Schlottmann, Anne; Ray, Elizabeth

2010-01-01

We investigated perception of social and physical causality and animacy in simple motion events, for high-functioning children with autism (CA = 13, VMA = 9.6). Children matched 14 different animations to pictures showing physical, social or non-causality. In contrast to previous work, children with autism performed at a high level similar to VMA-matched controls, recognizing physical causality in launch and social causality in reaction events. The launch deficit previously found in younger children with autism, possibly related to attentional/verbal difficulties, is apparently overcome with age. Some events involved squares moving non-rigidly, like animals. Children with autism had difficulties recognizing this, extending the biological motion literature. However, animacy prompts amplified their attributions of social causality. Thus children with autism may overcome their animacy perception deficit strategically.

Full cycle trigonometric function on Intel Quartus II Verilog

NASA Astrophysics Data System (ADS)

Mustapha, Muhazam; Zulkarnain, Nur Antasha

2018-02-01

This paper discusses about an improvement of a previous research on hardware based trigonometric calculations. Tangent function will also be implemented to get a complete set. The functions have been simulated using Quartus II where the result will be compared to the previous work. The number of bits has also been extended for each trigonometric function. The design is based on RTL due to its resource efficient nature. At earlier stage, a technology independent test bench simulation was conducted on ModelSim due to its convenience in capturing simulation data so that accuracy information can be obtained. On second stage, Intel/Altera Quartus II will be used to simulate on technology dependent platform, particularly on the one belonging to Intel/Altera itself. Real data on no. logic elements used and propagation delay have also been obtained.

Helicopter Fuselage Active Flow Control in the Presence of a Rotor

NASA Technical Reports Server (NTRS)

Martin, Preston B; Overmeyer, Austin D.; Tanner, Philip E.; Wilson, Jacob S.; Jenkins, Luther N.

2014-01-01

This work extends previous investigations of active flow control for helicopter fuselage drag and download reduction to include the effects of the rotor. The development of the new wind tunnel model equipped with fluidic oscillators is explained in terms of the previous test results. Large drag reductions greater than 20% in some cases were measured during powered testing without increasing, and in some cases decreasing download in forward flight. As confirmed by Particle Image Velocimetry (PIV), the optimum actuator configuration that provided a decrease in both drag and download appeared to create a virtual (fluidic) boat-tail fairing instead of attaching flow to the ramp surface. This idea of a fluidic fairing shifts the focus of 3D separation control behind bluff bodies from controlling/reattaching surface boundary layers to interacting with the wake flow.

Global Solutions for the zero-energy Novikov–Veselov equation by inverse scattering

NASA Astrophysics Data System (ADS)

Music, Michael; Perry, Peter

2018-07-01

Using the inverse scattering method, we construct global solutions to the Novikov–Veselov equation for real-valued decaying initial data q 0 with the property that the associated Schrödinger operator is nonnegative. Such initial data are either critical (an arbitrarily small perturbation of the potential makes the operator nonpositive) or subcritical (sufficiently small perturbations of the potential preserve non-negativity of the operator). Previously, Lassas, Mueller, Siltanen and Stahel proved global existence for critical potentials, also called potentials of conductivity type. We extend their results to include the much larger class of subcritical potentials. We show that the subcritical potentials form an open set and that the critical potentials form the nowhere dense boundary of this open set. Our analysis draws on previous work of the first author and on ideas of Grinevich and Manakov.

Periodicity of Strong Seismicity in Italy: Schuster Spectrum Analysis Extended to the Destructive Earthquakes of 2016

NASA Astrophysics Data System (ADS)

Bragato, P. L.

2017-10-01

The strong earthquakes that occurred in Italy between 2009 and 2016 represent an abrupt acceleration of seismicity in respect of the previous 30 years. Such behavior seems to agree with the periodic rate change I observed in a previous paper. The present work improves that study by extending the data set up to the end of 2016, adopting the latest version of the historical seismic catalog of Italy, and introducing Schuster spectrum analysis for the detection of the oscillatory period and the assessment of its statistical significance. Applied to the declustered catalog of M w ≥ 6 earthquakes that occurred between 1600 and 2016, the analysis individuates a marked periodicity of 46 years, which is recognized above the 95% confidence level. Monte Carlo simulation shows that the oscillatory behavior is stable in respect of random errors on magnitude estimation. A parametric oscillatory model for the annual rate of seismicity is estimated by likelihood maximization under the hypothesis of inhomogeneous Poisson point process. According to the Akaike Information Criterion, such model outperforms the simpler homogeneous one with constant annual rate. A further element emerges form the analysis: so far, despite recent earthquakes, the Italian seismicity is still within a long-term decreasing trend established since the first half of the twentieth century.

Extending Structural Analyses of the Rosenberg Self-Esteem Scale to Consider Criterion-Related Validity: Can Composite Self-Esteem Scores Be Good Enough?

PubMed

Donnellan, M Brent; Ackerman, Robert A; Brecheen, Courtney

2016-01-01

Although the Rosenberg Self-Esteem Scale (RSES) is the most widely used measure of global self-esteem in the literature, there are ongoing disagreements about its factor structure. This methodological debate informs how the measure should be used in substantive research. Using a sample of 1,127 college students, we test the overall fit of previously specified models for the RSES, including a newly proposed bifactor solution (McKay, Boduszek, & Harvey, 2014 ). We extend previous work by evaluating how various latent factors from these structural models are related to a set of criterion variables frequently studied in the self-esteem literature. A strict unidimensional model poorly fit the data, whereas models that accounted for correlations between negatively and positively keyed items tended to fit better. However, global factors from viable structural models had similar levels of association with criterion variables and with the pattern of results obtained with a composite global self-esteem variable calculated from observed scores. Thus, we did not find compelling evidence that different structural models had substantive implications, thereby reducing (but not eliminating) concerns about the integrity of the self-esteem literature based on overall composite scores for the RSES.

Using event-related fMRI to examine sustained attention processes and effects of APOE ε4 in young adults.

PubMed

Evans, Simon; Clarke, Devin; Dowell, Nicholas G; Tabet, Naji; King, Sarah L; Hutton, Samuel B; Rusted, Jennifer M

2018-01-01

In this study we investigated effects of the APOE ε4 allele (which confers an enhanced risk of poorer cognitive ageing, and Alzheimer's Disease) on sustained attention (vigilance) performance in young adults using the Rapid Visual Information Processing (RVIP) task and event-related fMRI. Previous fMRI work with this task has used block designs: this study is the first to image an extended (6-minute) RVIP task. Participants were 26 carriers of the APOE ε4 allele, and 26 non carriers (aged 18-28). Pupil diameter was measured throughout, as an index of cognitive effort. We compared activity to RVIP task hits to hits on a control task (with similar visual parameters and response requirements but no working memory load): this contrast showed activity in medial frontal, inferior and superior parietal, temporal and visual cortices, consistent with previous work, demonstrating that meaningful neural data can be extracted from the RVIP task over an extended interval and using an event-related design. Behavioural performance was not affected by genotype; however, a genotype by condition (experimental task/control task) interaction on pupil diameter suggested that ε4 carriers deployed more effort to the experimental compared to the control task. fMRI results showed a condition by genotype interaction in the right hippocampal formation: only ε4 carriers showed downregulation of this region to experimental task hits versus control task hits. Experimental task beta values were correlated against hit rate: parietal correlations were seen in ε4 carriers only, frontal correlations in non-carriers only. The data indicate that, in the absence of behavioural differences, young adult ε4 carriers already show a different linkage between functional brain activity and behaviour, as well as aberrant hippocampal recruitment patterns. This may have relevance for genotype differences in cognitive ageing trajectories.

Impact and Collisional Processes in the Solar System

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.

2001-01-01

In the past year, we have successfully developed the techniques necessary to conduct impact experiments on ice at very low temperatures. We employ the method of embedding gauges within a target to measure the shock wave and material properties. This means that our data are not model dependent; we directly measure the essential parameters needed for numerical simulations of impact cratering. Since then we have developed a new method for temperature control of icy targets that ensures temperature equilibrium throughout a porous target. Graduate student, Sarah Stewart-Mukhopadhyay, is leading the work on ices and porous materials as the main thrust of her thesis research. Our previous work has focused on icy materials with no porosity, and we propose to extend our research to include porous ice and porous ice-silicate mixtures. There is little shockwave data for porous ice, and none of the data was acquired under conditions applicable to the outer solar system. The solid ice Hugoniot is only defined for initial temperatures above -20 C. Our program uniquely measures the properties of ice at temperatures directly applicable to the solar system. Previous experiments were conducted at ambient temperatures soon after removing the target from a cold environment, usually just below freezing, or in a room just below freezing. Since ice has an extremely complicated phase diagram, it is important to conduct experiments at lower temperatures to determine the true outcome of impacts in the outer solar system. This research is complementary to other programs on icy materials. Our work focuses on the inherent material properties by measuring the shock wave directly; this complements the macroscopic observations and immediately provides the parameters necessary to extend this research to the gravity regime. Our numerical simulations of impacts in porous ice under very low gravity conditions, such as found on comets, show that the final crater size and shape is very dependent on the dynamic strength of the material.

Determination of Realistic Fire Scenarios in Spacecraft

NASA Technical Reports Server (NTRS)

Dietrich, Daniel L.; Ruff, Gary A.; Urban, David

2013-01-01

This paper expands on previous work that examined how large a fire a crew member could successfully survive and extinguish in the confines of a spacecraft. The hazards to the crew and equipment during an accidental fire include excessive pressure rise resulting in a catastrophic rupture of the vehicle skin, excessive temperatures that burn or incapacitate the crew (due to hyperthermia), carbon dioxide build-up or accumulation of other combustion products (e.g. carbon monoxide). The previous work introduced a simplified model that treated the fire primarily as a source of heat and combustion products and sink for oxygen prescribed (input to the model) based on terrestrial standards. The model further treated the spacecraft as a closed system with no capability to vent to the vacuum of space. The model in the present work extends this analysis to more realistically treat the pressure relief system(s) of the spacecraft, include more combustion products (e.g. HF) in the analysis and attempt to predict the fire spread and limiting fire size (based on knowledge of terrestrial fires and the known characteristics of microgravity fires) rather than prescribe them in the analysis. Including the characteristics of vehicle pressure relief systems has a dramatic mitigating effect by eliminating vehicle overpressure for all but very large fires and reducing average gas-phase temperatures.

Repetition, response mobilization, and face: Analysis of group interactions with a 19-year-old with Asperger syndrome.

PubMed

Bottema-Beutel, Kristen; Louick, Rebecca; White, Rachael

2015-01-01

This Conversation Analytic study examined the talk of an adolescent with Asperger syndrome (under previously used diagnostic criteria), Nathan, as he interacts with peers in a small group setting. We focused on Nathan's repetition aimed at pursuing response, and rely on analytical frameworks including response mobilization, face-work, and agreement preference. We found that while Nathan's repetitions resembled 'topic perseveration' previously described in the literature, they showed evidence of interactional awareness as they were employed when peers offered little or no response to his original utterance. However, we also found that while much of Nathan's talk was sophisticatedly structured, his repetition to pursue response eschewed interaction rituals that work to maintain social cohesion. As a result, Nathan's interactional priorities appeared mis-aligned with those of his peers, and failed to produce extended interactions in most cases. Readers will be able to describe features of conversational interaction, including response mobilization, agreement preference, and face work. They will understand the relevance of conversation analysis to the study of interaction in individuals with autism spectrum disorder. Lastly, they will be able to describe the conditions under which the subject used repetition within peer interactions, and the effects of his repetition on interaction. Copyright © 2015 Elsevier Inc. All rights reserved.

Extending Automatic Parallelization to Optimize High-Level Abstractions for Multicore

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

Liao, C; Quinlan, D J; Willcock, J J

2008-12-12

Automatic introduction of OpenMP for sequential applications has attracted significant attention recently because of the proliferation of multicore processors and the simplicity of using OpenMP to express parallelism for shared-memory systems. However, most previous research has only focused on C and Fortran applications operating on primitive data types. C++ applications using high-level abstractions, such as STL containers and complex user-defined types, are largely ignored due to the lack of research compilers that are readily able to recognize high-level object-oriented abstractions and leverage their associated semantics. In this paper, we automatically parallelize C++ applications using ROSE, a multiple-language source-to-source compiler infrastructuremore » which preserves the high-level abstractions and gives us access to their semantics. Several representative parallelization candidate kernels are used to explore semantic-aware parallelization strategies for high-level abstractions, combined with extended compiler analyses. Those kernels include an array-base computation loop, a loop with task-level parallelism, and a domain-specific tree traversal. Our work extends the applicability of automatic parallelization to modern applications using high-level abstractions and exposes more opportunities to take advantage of multicore processors.« less

Testing framework for embedded languages

NASA Astrophysics Data System (ADS)

Leskó, Dániel; Tejfel, Máté

2012-09-01

Embedding a new programming language into an existing one is a widely used technique, because it fastens the development process and gives a part of a language infrastructure for free (e.g. lexical, syntactical analyzers). In this paper we are presenting a new advantage of this development approach regarding to adding testing support for these new languages. Tool support for testing is a crucial point for a newly designed programming language. It could be done in the hard way by creating a testing tool from scratch, or we could try to reuse existing testing tools by extending them with an interface to our new language. The second approach requires less work, and also it fits very well for the embedded approach. The problem is that the creation of such interfaces is not straightforward at all, because the existing testing tools were mostly not designed to be extendable and to be able to deal with new languages. This paper presents an extendable and modular model of a testing framework, in which the most basic design decision was to keep the - previously mentioned - interface creation simple and straightforward. Other important aspects of our model are the test data generation, the oracle problem and the customizability of the whole testing phase.

Quasispecies dynamics on a network of interacting genotypes and idiotypes: formulation of the model

NASA Astrophysics Data System (ADS)

Barbosa, Valmir C.; Donangelo, Raul; Souza, Sergio R.

2015-01-01

A quasispecies is the stationary state of a set of interrelated genotypes that evolve according to the usual principles of selection and mutation. Quasispecies studies have for the most part concentrated on the possibility of errors during genotype replication and their role in promoting either the survival or the demise of the quasispecies. In a previous work, we introduced a network model of quasispecies dynamics, based on a single probability parameter (p) and capable of addressing several plausibility issues of previous models. Here we extend that model by pairing its network with another one aimed at modeling the dynamics of the immune system when confronted with the quasispecies. The new network is based on the idiotypic-network model of immunity and, together with the previous one, constitutes a network model of interacting genotypes and idiotypes. The resulting model requires further parameters and as a consequence leads to a vast phase space. We have focused on a particular niche in which it is possible to observe the trade-offs involved in the quasispecies' survival or destruction. Within this niche, we give simulation results that highlight some key preconditions for quasispecies survival. These include a minimum initial abundance of genotypes relative to that of the idiotypes and a minimum value of p. The latter, in particular, is to be contrasted with the stand-alone quasispecies network of our previous work, in which arbitrarily low values of p constitute a guarantee of quasispecies survival.

The Pliocene Citronelle Formation of the Gulf Coastal Plain

USGS Publications Warehouse

Matson, George Charlton

1916-01-01

In the spring of 1910 the writer, working under the direction of T. Wayland Vaughan, geologist in charge of Coastal Plain investigations, undertook a study of the later Tertiary formations of the Gulf Coastal Plain. According to the plans outlined before the work was begun, the beds that had formerly been grouped under the names Lafayette formation and Grand Gulf formation were to be studied with a view to their possible separation into more satisfactory stratigraphic units that might be correlated with other formations which, on the basis of their fossils, had been assigned to their proper positions in the geologic time scale. The original plan included a study of the post-Vicksburgian Tertiary deposits from western Florida to Mississippi River and correlations with formations previously recognized in Florida, southern Alabama, and Louisiana. This plan was subsequently modified to extend the investigation as far west as Sabine River. The field work was interrupted and the office work was delayed by calls for geologic work in other areas, so that the preparation of the reports could not be begun until the spring of 1914.

Physical and cognitive capability in mid-adulthood as determinants of retirement and extended working life in a British cohort study.

PubMed

Stafford, Mai; Cooper, Rachel; Cadar, Dorina; Carr, Ewan; Murray, Emily; Richards, Marcus; Stansfeld, Stephen; Zaninotto, Paola; Head, Jenny; Kuh, Diana

2017-01-01

Objective Policy in many industrialized countries increasingly emphasizes extended working life. We examined associations between physical and cognitive capability in mid-adulthood and work in late adulthood. Methods Using self-reported physical limitations and performance-based physical and cognitive capability at age 53, assessed by trained nurses from the Medical Research Council (MRC) National Survey of Health and Development, we examined prospective associations with extended working (captured by age at and reason for retirement from main occupation, bridge employment in paid work after retirement from the main occupation, and voluntary work participation) up to age 68 among >2000 men and women. Results Number of reported physical limitations at age 53 was associated with higher likelihood of retiring for negative reasons and lower likelihood of participating in bridge employment, adjusted for occupational class, education, partner's employment, work disability at age 53, and gender. Better performance on physical and cognitive tests was associated with greater likelihood of participating in bridge or voluntary work. Cognitive capability in the top 10% compared with the middle 80% of the distribution was associated with an odds ratio of bridge employment of 1.71 [95% confidence interval (95% CI) 1.21-2.42]. Conclusions The possibility for an extending working life is less likely to be realized by those with poorer midlife physical or cognitive capability, independently of education, and social class. Interventions to promote capability, starting in mid-adulthood or earlier, could have long-term consequences for extending working.

A Latent Variables Examination of Processing Speed, Response Inhibition, and Working Memory during Typical Development

PubMed Central

McAuley, Tara; White, Desirée

2010-01-01

The present study addressed three related aims: (1) to replicate and extend previous work regarding the non-unitary nature of processing speed, response inhibition, and working memory during development, (2) to quantify the rate at which processing speed, response inhibition, and working memory develop and the extent to which the development of these latter abilities reflect general changes in processing speed, and (3) to evaluate whether commonly used tasks of processing speed, response inhibition, and working memory are valid and reliable when used with a developmentally diverse group. To address these aims, a latent variables approach was used to analyze data from 147 participants 6 to 24 years of age. Results showed that processing speed, response inhibition, and working memory were separable abilities and that the extent of this separability was stable cross the age range of participants. All three constructs improved as a function of age; however, only the effect of age on working memory remained significant after processing speed was controlled. The psychometric properties of tasks used to assess the constructs were age invariant, thus validating their use in studies of executive development. PMID:20888572

What works with worked examples: Extending self-explanation and analogical comparison to synthesis problems

NASA Astrophysics Data System (ADS)

Badeau, Ryan; White, Daniel R.; Ibrahim, Bashirah; Ding, Lin; Heckler, Andrew F.

2017-12-01

The ability to solve physics problems that require multiple concepts from across the physics curriculum—"synthesis" problems—is often a goal of physics instruction. Three experiments were designed to evaluate the effectiveness of two instructional methods employing worked examples on student performance with synthesis problems; these instructional techniques, analogical comparison and self-explanation, have previously been studied primarily in the context of single-concept problems. Across three experiments with students from introductory calculus-based physics courses, both self-explanation and certain kinds of analogical comparison of worked examples significantly improved student performance on a target synthesis problem, with distinct improvements in recognition of the relevant concepts. More specifically, analogical comparison significantly improved student performance when the comparisons were invoked between worked synthesis examples. In contrast, similar comparisons between corresponding pairs of worked single-concept examples did not significantly improve performance. On a more complicated synthesis problem, self-explanation was significantly more effective than analogical comparison, potentially due to differences in how successfully students encoded the full structure of the worked examples. Finally, we find that the two techniques can be combined for additional benefit, with the trade-off of slightly more time on task.

Input dependent cell assembly dynamics in a model of the striatal medium spiny neuron network.

PubMed

Ponzi, Adam; Wickens, Jeff

2012-01-01

The striatal medium spiny neuron (MSN) network is sparsely connected with fairly weak GABAergic collaterals receiving an excitatory glutamatergic cortical projection. Peri-stimulus time histograms (PSTH) of MSN population response investigated in various experimental studies display strong firing rate modulations distributed throughout behavioral task epochs. In previous work we have shown by numerical simulation that sparse random networks of inhibitory spiking neurons with characteristics appropriate for UP state MSNs form cell assemblies which fire together coherently in sequences on long behaviorally relevant timescales when the network receives a fixed pattern of constant input excitation. Here we first extend that model to the case where cortical excitation is composed of many independent noisy Poisson processes and demonstrate that cell assembly dynamics is still observed when the input is sufficiently weak. However if cortical excitation strength is increased more regularly firing and completely quiescent cells are found, which depend on the cortical stimulation. Subsequently we further extend previous work to consider what happens when the excitatory input varies as it would when the animal is engaged in behavior. We investigate how sudden switches in excitation interact with network generated patterned activity. We show that sequences of cell assembly activations can be locked to the excitatory input sequence and outline the range of parameters where this behavior is shown. Model cell population PSTH display both stimulus and temporal specificity, with large population firing rate modulations locked to elapsed time from task events. Thus the random network can generate a large diversity of temporally evolving stimulus dependent responses even though the input is fixed between switches. We suggest the MSN network is well suited to the generation of such slow coherent task dependent response which could be utilized by the animal in behavior.

Input Dependent Cell Assembly Dynamics in a Model of the Striatal Medium Spiny Neuron Network

PubMed Central

Ponzi, Adam; Wickens, Jeff

2012-01-01

The striatal medium spiny neuron (MSN) network is sparsely connected with fairly weak GABAergic collaterals receiving an excitatory glutamatergic cortical projection. Peri-stimulus time histograms (PSTH) of MSN population response investigated in various experimental studies display strong firing rate modulations distributed throughout behavioral task epochs. In previous work we have shown by numerical simulation that sparse random networks of inhibitory spiking neurons with characteristics appropriate for UP state MSNs form cell assemblies which fire together coherently in sequences on long behaviorally relevant timescales when the network receives a fixed pattern of constant input excitation. Here we first extend that model to the case where cortical excitation is composed of many independent noisy Poisson processes and demonstrate that cell assembly dynamics is still observed when the input is sufficiently weak. However if cortical excitation strength is increased more regularly firing and completely quiescent cells are found, which depend on the cortical stimulation. Subsequently we further extend previous work to consider what happens when the excitatory input varies as it would when the animal is engaged in behavior. We investigate how sudden switches in excitation interact with network generated patterned activity. We show that sequences of cell assembly activations can be locked to the excitatory input sequence and outline the range of parameters where this behavior is shown. Model cell population PSTH display both stimulus and temporal specificity, with large population firing rate modulations locked to elapsed time from task events. Thus the random network can generate a large diversity of temporally evolving stimulus dependent responses even though the input is fixed between switches. We suggest the MSN network is well suited to the generation of such slow coherent task dependent response which could be utilized by the animal in behavior. PMID:22438838

Characterization of aerosol scattering and spectral absorption by unique methods: a polar/imaging nephelometer and spectral reflectance measurements of aerosol samples collected on filters

NASA Astrophysics Data System (ADS)

Dolgos, Gergely; Martins, J. Vanderlei; Remer, Lorraine A.; Correia, Alexandre L.; Tabacniks, Manfredo; Lima, Adriana R.

2010-02-01

Characterization of aerosol scattering and absorption properties is essential to accurate radiative transfer calculations in the atmosphere. Applications of this work include remote sensing of aerosols, corrections for aerosol distortions in satellite imagery of the surface, global climate models, and atmospheric beam propagation. Here we demonstrate successful instrument development at the Laboratory for Aerosols, Clouds and Optics at UMBC that better characterizes aerosol scattering phase matrix using an imaging polar nephelometer (LACO-I-Neph) and enables measurement of spectral aerosol absorption from 200 nm to 2500 nm. The LACO-I-Neph measures the scattering phase function from 1.5° to 178.5° scattering angle with sufficient sensitivity to match theoretical expectations of Rayleigh scattering of various gases. Previous measurements either lack a sufficiently wide range of measured scattering angles or their sensitivity is too low and therefore the required sample amount is prohibitively high for in situ measurements. The LACO-I-Neph also returns expected characterization of the linear polarization signal of Rayleigh scattering. Previous work demonstrated the ability of measuring spectral absorption of aerosol particles using a reflectance technique characterization of aerosol samples collected on Nuclepore filters. This first generation methodology yielded absorption measurements from 350 nm to 2500 nm. Here we demonstrate the possibility of extending this wavelength range into the deep UV, to 200 nm. This extended UV region holds much promise in identifying and characterizing aerosol types and species. The second generation, deep UV, procedure requires careful choice of filter substrates. Here the choice of substrates is explored and preliminary results are provided.

Solar Polar Jets Driven by Magnetic Reconnection, Gravity, and Wind

NASA Astrophysics Data System (ADS)

DeVore, C. Richard; Karpen, Judith T.; Antiochos, Spiro K.

2014-06-01

Polar jets are dynamic, narrow, radially extended structures observed in solar EUV emission near the limb. They originate within the open field of coronal holes in “anemone” regions, which are intrusions of opposite magnetic polarity. The key topological feature is a magnetic null point atop a dome-shaped fan surface of field lines. Applied stresses readily distort the null into a current patch, eventually inducing interchange reconnection between the closed and open fields inside and outside the fan surface (Antiochos 1996). Previously, we demonstrated that magnetic free energy stored on twisted closed field lines inside the fan surface is released explosively by the onset of fast reconnection across the current patch (Pariat et al. 2009, 2010). A dense jet comprised of a nonlinear, torsional Alfvén wave is ejected into the outer corona along the newly reconnected open field lines. Now we are extending those exploratory simulations by including the effects of solar gravity, solar wind, and expanding spherical geometry. We find that the model remains robust in the resulting more complex setting, with explosive energy release and dense jet formation occurring in the low corona due to the onset of a kink-like instability, as found in the earlier Cartesian, gravity-free, static-atmosphere cases. The spherical-geometry jet including gravity and wind propagates far more rapidly into the outer corona and inner heliosphere than a comparison jet simulation that excludes those effects. We report detailed analyses of our new results, compare them with previous work, and discuss the implications for understanding remote and in-situ observations of solar polar jets.This work was supported by NASA’s LWS TR&T program.

Decadal prediction of Sahel rainfall: where does the skill (or lack thereof) come from?

NASA Astrophysics Data System (ADS)

Mohino, Elsa; Keenlyside, Noel; Pohlmann, Holger

2016-12-01

Previous works suggest decadal predictions of Sahel rainfall could be skillful. However, the sources of such skill are still under debate. In addition, previous results are based on short validation periods (i.e. less than 50 years). In this work we propose a framework based on multi-linear regression analysis to study the potential sources of skill for predicting Sahel trends several years ahead. We apply it to an extended decadal hindcast performed with the MPI-ESM-LR model that span from 1901 to 2010 with 1 year sampling interval. Our results show that the skill mainly depends on how well we can predict the timing of the global warming (GW), the Atlantic multidecadal variability (AMV) and, to a lesser extent, the inter-decadal Pacific oscillation signals, and on how well the system simulates the associated SST and West African rainfall response patterns. In the case of the MPI-ESM-LR decadal extended hindcast, the observed timing is well reproduced only for the GW and AMV signals. However, only the West African rainfall response to the AMV is correctly reproduced. Thus, for most of the lead times the main source of skill in the decadal hindcast of West African rainfall is from the AMV. The GW signal degrades skill because the response of West African rainfall to GW is incorrectly captured. Our results also suggest that initialized decadal predictions of West African rainfall can be further improved by better simulating the response of global SST to GW and AMV. Furthermore, our approach may be applied to understand and attribute prediction skill for other variables and regions.

Taking a fresh look at optical crowding of TiO2: the role of nanocarbonate as synergistic optical extender

NASA Astrophysics Data System (ADS)

Ridgway, Cathy J.; Gane, Patrick A. C.

2013-10-01

The light scattering potential of titanium dioxide (TiO2) is maximized when the TiO2 particles are correctly spaced in relation to the size of the particles, their spacing distance and the refractive index contrast with the surrounding medium. Nanoparticle extenders are claimed to improve TiO2 spacing due to the small particles acting to separate larger TiO2 particles (void size in respect to the separation of the surfaces ˜0.2 µm) and so preventing the TiO2 particles from reaching optical crowding. This concept has been challenged by previous work (Diebold 2011 J. Coat. Technol. Res. 8 541-52) using a combination of Monte Carlo simulations and image analysis techniques. Surprisingly in the light of traditional interpretations, the results showed that nanoparticles did not, in fact, space TiO2 particles under any conditions examined. Instead, TiO2 distributions and spacings were completely indifferent to the presence of smaller particles. This current paper undertakes to study why in certain cases extenders do in fact deliver significant synergy allowing TiO2 levels to be reduced in practice. The use of nano-calcium carbonate is demonstrated to provide a wide range of synergistic extension of TiO2 when in combination with synthetic latex binder, but, as found in the previous theoretical work, only a limited synergistic range in direct pigment packing studies using slurry pigment mixes only. A schematic model of the action of calcium carbonate containing a high nanoparticle fraction in the presence of binder is proposed, and is related to a combination of the potential reduction of contact between latex and TiO2 related to an increase in effective pigment volume fraction and surface area as well as the potential for differential flocculation. This model is supported by electron microscopy images and a measure of the ‘hardness’ of the skeletal elements making up the coating structure, determined via the bulk modulus using mercury intrusion porosimetry, enabling the effective incompressible pigment volume fraction in relation to compressible binder to be identified.

Students Working Online for Group Projects: A Test of an Extended Theory of Planned Behaviour Model

ERIC Educational Resources Information Center

Cheng, Eddie W. L.

2017-01-01

This study examined an extended theory of planned behaviour (TPB) model that specified factors affecting students' intentions to collaborate online for group work. Past behaviour, past experience and actual behavioural control were incorporated in the extended TPB model. The mediating roles of attitudes, subjective norms and perceived behavioural…

Local properties of magnetic reconnection in nonlinear resistive- and extended-magnetohydrodynamic toroidal simulations of the sawtooth crash

DOE PAGES

Beidler, M. T.; Cassak, P. A.; Jardin, S. C.; ...

2016-12-15

We diagnose local properties of magnetic reconnection during a sawtooth crash employing the three-dimensional toroidal, extended-magnetohydrodynamic (MHD) code M3D-C 1. To do so, we sample simulation data in the plane in which reconnection occurs, the plane perpendicular to the helical (m, n) = (1, 1) mode at the q = 1 surface, where m and n are the poloidal and toroidal mode numbers and q is the safety factor. We study the nonlinear evolution of a particular test equilibrium in a non-reduced field representation using both resistive-MHD and extended-MHD models. We find growth rates for the extended-MHD reconnection process exhibitmore » a nonlinear acceleration and greatly exceed that of the resistive-MHD model, as is expected from previous experimental, theoretical, and computational work. We compare the properties of reconnection in the two simulations, revealing the reconnecting current sheets are locally different in the two models and we present the first observation of the quadrupole out-of-plane Hall magnetic field that appears during extended-MHD reconnection in a 3D toroidal simulation (but not in resistive-MHD). We also explore the dependence on toroidal angle of the properties of reconnection as viewed in the plane perpendicular to the helical magnetic field, finding qualitative and quantitative effects due to changes in the symmetry of the reconnection process. Furthermore, this study is potentially important for a wide range of magnetically confined fusion applications, from confirming simulations with extended-MHD effects are sufficiently resolved to describe reconnection, to quantifying local reconnection rates for purposes of understanding and predicting transport, not only at the q = 1 rational surface for sawteeth, but also at higher order rational surfaces that play a role in disruptions and edge-confinement degradation.« less

Eighteenth annual report of the United States Geological Survey to the Secretary of the Interior, 1896-1897: Part IV - Hydrography

USGS Publications Warehouse

Davis, Arthur Powell; Leverett, Frank; Darton, N.H.; Schuyler, J.D.

1897-01-01

The completion of this volume marks the revival of extended systematic investigation of the hydrography of the United State. This book is, in effect, the ninth annual report of what has been known as the Irrigation Survey. Its preparation and publication has been made possible by the act of June 11, 1896 (Stat. L., vol. 29, p. 436), which enlarged the scope of the work and authorized the preparation of reports upon the best methods of utilizing the water resources of arid and semiarid sections. For some years before this date the sums available for hydrographic work were so small that it was practicable merely to continue observations at previously established stations, compute discharges, and compile for publication the data accumulated in the office.

Autobiographical integration of trauma memories and repressive coping predict post-traumatic stress symptoms in undergraduate students.

PubMed

Smeets, Tom; Giesbrecht, Timo; Raymaekers, Linsey; Shaw, Julia; Merckelbach, Harald

2010-01-01

What differentiates those who are able to adapt well to adverse life events (i.e., persons who are resilient) from those who are not (e.g., persons who develop post-traumatic stress symptoms)? Previous work suggests that enhanced autobiographical integration of trauma memories is associated with more severe post-traumatic stress symptoms. Extending this line of work, the present study looked at whether the integration of trauma memories, repressive coping and cognitive reactivity are related to post-traumatic stress symptomatology following negative life events among otherwise healthy young adults (N = 213). Results show that while enhanced integration of trauma memories and high levels of dissociation are related to elevated levels of post-traumatic stress, people who generally engage in repressive coping report fewer post-traumatic stress symptoms. Copyright (c) 2009 John Wiley & Sons, Ltd.

Anxiety sensitivity as a mediator of the relationship between moderate-intensity exercise and coping-oriented marijuana use motives.

PubMed

Smits, Jasper A J; Bonn-Miller, Marcel O; Tart, Candyce D; Irons, Jessica G; Zvolensky, Michael J

2011-01-01

The present study examined the working hypothesis that moderate-intensity exercise is associated with coping-oriented marijuana use motives through its association with the fear of somatic arousal (ie, anxiety sensitivity). Using data from 146 young adult current marijuana users, we found evidence consistent with this hypothesis. Specifically, moderate-intensity exercise was associated with coping-oriented use motives, even after controlling for frequency of current marijuana use and other co-occurring marijuana use motives. This relationship became nonsignificant after entering anxiety sensitivity as an additional predictor variable, denoting a putative mediational role for this cognitive factor. These findings extend previous work and offer support for the potential utility of moderate-intensity aerobic exercise for the treatment of marijuana use problems. © American Academy of Addiction Psychiatry.

Cosmic strings and the microwave sky. I - Anisotropy from moving strings

NASA Technical Reports Server (NTRS)

Stebbins, Albert

1988-01-01

A method is developed for calculating the component of the microwave anisotropy around cosmic string loops due to their rapidly changing gravitational fields. The method is only valid for impact parameters from the string much smaller than the horizon size at the time the photon passes the string. The method makes it possible to calculate the temperature pattern around arbitrary string configurations numerically in terms of one-dimensional integrals. This method is applied to temperature jump across a string, confirming and extending previous work. It is also applied to cusps and kinks on strings, and to determining the temperature pattern far from a strong loop. The temperature pattern around a few loop configurations is explicitly calculated. Comparisons with the work of Brandenberger et al. (1986) indicates that they have overestimated the MBR anisotropy from gravitational radiation emitted from loops.

Screening protocols for the prevention of occupational noise-induced hearing loss: the role of conventional and extended high frequency audiometry may vary according to the years of employment.

PubMed

Riga, Maria; Korres, George; Balatsouras, Dimitrios; Korres, Stavros

2010-07-01

Although occupational noise-induced hearing loss (NIHL) has become a major problem in industrialized societies, there is a notable lack of effective screening protocols to ensure its early diagnosis. The aim of this study was to detect a potential role of extended high frequency (EHF) audiometry in industrial hearing screening protocols. The population consisted of 151 persons, working for 8 hours daily in a noisy environment (90-110 dBA). The changes of hearing thresholds in industrial workers were analyzed, not only with respect to their age, as has been presented by previous studies, but also with respect to the duration of their previous employment. During the first 10 years of employment, the frequencies 12500, 14000 and 16000Hz were the only ones significantly affected. For the second decade of employment, thresholds were significantly elevated only at 2000 and 4000Hz. After exceeding 20 years of employment, the affected frequencies were 250, 500 and 1000Hz. The effects of age on hearing acuity were significant at all frequencies for the first 2 groups. EHF audiometry seems able to identify the first signs of NIHL, much earlier than conventional audiometry, and therefore may need to be implemented in the screening examinations especially of workers with less than 1 decade of employment. Hearing screening protocols could become more efficient by adjusting their frequency ranges according to the frequencies "at risk", which correspond to the duration of the workers' previous employment.

Structural and functional role of bases 32 and 33 in the anticodon loop of yeast mitochondrial tRNAIle

PubMed Central

Montanari, Arianna; De Luca, Cristina; Di Micco, Patrizio; Morea, Veronica; Frontali, Laura; Francisci, Silvia

2011-01-01

Previous work has demonstrated the usefulness of the yeast model to investigate the molecular mechanisms underlying defects due to base substitutions in mitochondrial tRNA genes, and to identify suppressing molecules endowed with potential clinical relevance. The present paper extends these investigations to two human equivalent yeast mutations located at positions 32 and 33 in the anticodon loop of tRNAIle. Notwithstanding the proximity of the two T>C base substitutions, the effects of these mutations have been found to be quite different in yeast, as they are in human. The T32C substitution has a very severe effect in yeast, consisting in a complete inhibition of growth on nonfermentable substrates. Conversely, respiratory defects caused by the T33C mutation could only be observed in a defined genetic context. Analyses of available sequences and selected tRNA three-dimensional structures were performed to provide explanations for the different behavior of these adjacent mutations. Examination of the effects of previously identified suppressors demonstrated that overexpression of the TUF1 gene did not rescue the defective phenotypes determined by either mutation, possibly as a consequence of the lack of interactions between EF-Tu and the tRNA anticodon arm in known structures. On the contrary, both the cognate IleRS and the noncognate LeuRS and ValRS are endowed with suppressing activities toward both mutations. This allows us to extend to the tRNAIle mutants the cross-suppression activity of aminoacyl-tRNA synthetases previously demonstrated for tRNALeu and tRNAVal mutants. PMID:21914842

77 FR 40834 - Proposed Amendment of Class E Airspace; Dillon, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-11

... further expand the previous proposed amendment of Class E airspace extending upward from 700 feet above... an amendment of Class E airspace extending upward from 700 feet above the surface. DATES: Comments... published a NPRM to modify Class E airspace, extending upward from 700 feet or more above the surface, at...

Quantum molecular dynamics of warm dense iron and a five-phase equation of state

NASA Astrophysics Data System (ADS)

Sjostrom, Travis; Crockett, Scott

2018-05-01

Through quantum molecular dynamics (QMD), utilizing both Kohn-Sham (orbital-based) and orbital-free density functional theory, we calculate the equation of state of warm dense iron in the density range 7 -30 g/cm 3 and temperatures from 1 to 100 eV. A critical examination of the iron pseudopotential is made, from which we find a significant improvement at high pressure to the previous QMD calculations of Wang et al. [Phys. Rev. E 89, 023101 (2014), 10.1103/PhysRevE.89.023101]. Our results also significantly extend the ranges of density and temperature that were attempted in that prior work. We calculate the shock Hugoniot and find very good agreement with experimental results to pressures over 20 TPa. These results are then incorporated with previous studies to generate a five-phase equation of state for iron.

Simulating the Effects of Cross-Generational Cultural Transmission on Language Change

NASA Astrophysics Data System (ADS)

Gong, Tao; Shuai, Lan

Language evolves in a socio-cultural environment. Apart from biological evolution and individual learning, cultural transmission also casts important influence on many aspects of language evolution. In this paper, based on the lexicon-syntax coevolution model, we extend the acquisition framework in our previous work to examine the roles of three forms of cultural transmission spanning the offspring, parent, and grandparent generations in language change. These transmissions are: those between the parent and offspring generations (PO), those within the offspring generation (OO), and those between the grandparent and offspring generations (GO). The simulation results of the considered model and relevant analyses illustrate not only the necessity of PO and OO transmissions for language change, thus echoing our previous findings, but also the importance of GO transmission, a form of cross-generational cultural transmission, on preserving the mutual understandability of the communal language across generations of individuals.

A theoretical and flight test study of pressure fluctuations under a turbulent boundary layer. Part 2: Flight test study

NASA Technical Reports Server (NTRS)

Panton, R. L.; Lowery, R. L.; Reischman, M. M.

1967-01-01

The study of pressure fluctuations under a turbulent boundary layer was undertaken with the objective of extending previous work to lower frequencies. Wind tunnel and flight test measurements are invalid at low frequencies because of extraneous acoustic noises and free stream turbulence. A glider was instrumented and used as a test bed to carry microphones into a smooth flow free of acoustic noise. Hodgson had previously measured the spectrum of boundary layer noise on a glider wing. These tests showed a drop off at low frequencies that could not be reproduced in any other facility. The measurements were made on the forward fuselage of a glider where the boundary layer could develop naturally and have some length in a zero pressure gradient before the measurements were made. Two different sets of measurements were made.

An ecological process model of female sex offending: the role of victimization, psychological distress, and life stressors.

PubMed

DeCou, Christopher R; Cole, Trevor T; Rowland, Sarah E; Kaplan, Stephanie P; Lynch, Shannon M

2015-06-01

Female sex offenders may be implicated in up to one fifth of all sex crimes committed in the United States. Despite previous research findings that suggest unique patterns of offending among female sex offenders, limited empirical research has investigated the motivations and processes involved. The present study qualitatively examined female sex offenders' offense-related experiences and characterized the internal and external factors that contributed to offending. Semi-structured interviews with 24 female sex offenders were analyzed by a team of coders with limited exposure to the existing literature using grounded theory analysis. A conceptual framework emerged representing distinctive processes for solo- and co-offending, contextualized within ecological layers of social and environmental influence. This model extends previous work by offering an example of nested vulnerabilities proximal to female sexual offending. Implications for future research, prevention, and treatment are discussed. © The Author(s) 2014.

Statistical Mechanics Model of Solids with Defects

NASA Astrophysics Data System (ADS)

Kaufman, M.; Walters, P. A.; Ferrante, J.

1997-03-01

Previously(M.Kaufman, J.Ferrante,NASA Tech. Memor.,1996), we examined the phase diagram for the failure of a solid under isotropic expansion and compression as a function of stress and temperature with the "springs" modelled by the universal binding energy relation (UBER)(J.H.Rose, J.R.Smith, F.Guinea, J.Ferrante, Phys.Rev.B29, 2963 (1984)). In the previous calculation we assumed that the "springs" failed independently and that the strain is uniform. In the present work, we have extended this statistical model of mechanical failure by allowing for correlations between "springs" and for thermal fluctuations in strains. The springs are now modelled in the harmonic approximation with a failure threshold energy E0, as an intermediate step in future studies to reinclude the full non-linear dependence of the UBER for modelling the interactions. We use the Migdal-Kadanoff renormalization-group method to determine the phase diagram of the model and to compute the free energy.

Geodesic Motion of Particles and Quantum Tunneling from Reissner-Nordström Black Holes in Anti-de Sitter Spacetime

NASA Astrophysics Data System (ADS)

Deng, Gao-Ming; Huang, Yong-Chang

2018-03-01

The geodesics of tunneling particles were derived unnaturally and awkwardly in previous works. For one thing, the previous derivation was inconsistent with the variational principle of action. Moreover, the definition of geodesic equations for massive particles was quite different from that of massless case. Even worse, the relativistic and nonrelativistic foundations were mixed with each other during the past derivation of geodesics. As a highlight, remedying the urgent shortcomings, we improve treatment to derive the geodesic equations of massive and massless particles in a unified and self-consistent way. Besides, we extend to investigate the Hawking radiation via tunneling from Reissner-Nordström black holes in the context of AdS spacetime. Of special interest, the trick of utilizing the first law of black hole thermodynamics manifestly simplifies the calculation of tunneling integration.

Psychopathy, attention, and oddball target detection: New insights from PCL-R facet scores.

PubMed

Anderson, Nathaniel E; Steele, Vaughn R; Maurer, J Michael; Bernat, Edward M; Kiehl, Kent A

2015-09-01

Psychopathy is a disorder accompanied by cognitive deficits including abnormalities in attention. Prior studies examining cognitive features of psychopaths using ERPs have produced some inconsistent results. We examined psychopathy-related differences in ERPs during an auditory oddball task in a sample of incarcerated adult males. We extend previous work by deriving ERPs with principal component analysis (PCA) and relate these to the four facets of Hare's Psychopathy Checklist Revised (PCL-R). Features of psychopathy were associated with increased target N1 amplitude (facets 1, 4), decreased target P3 amplitude (facet 1), and reduced slow wave amplitude for frequent standard stimuli (facets 1, 3, 4). We conclude that employing PCA and examining PCL-R facets improve sensitivity and help clarify previously reported associations. Furthermore, attenuated slow wave during standards may be a novel marker for psychopaths' abnormalities in attention. © 2015 Society for Psychophysiological Research.

Acoustical radiation torque and force for spheres and Bessel beam extinction efficiency

NASA Astrophysics Data System (ADS)

Marston, Philip L.; Zhang, Likun

2014-11-01

The scattering of optical and acoustical beams is relevant to the levitation and manipulation of drops. Here we examine theoretical developments in the acoustical case. We previously showed how the optical theorem for extinction can be extended to invariant beams. The example of a sphere in a Bessel beam facilitates the direct comparison with a circular disc computed using Babinet's principle and the Kirchhoff approximation. In related work, by considering traveling or standing wave first-order vortex beams we previously showed that the radiation torque is the ratio of the absorbed power and the radian acoustic frequency. By modifying the scattering to account for the viscosity of the surrounding fluid in the analysis of the absorbed power, approximations for radiation torque and force are obtained at long wavelengths in special cases and these can be compared with results published elsewhere.

Methodes entropiques appliquees au probleme inverse en magnetoencephalographie

NASA Astrophysics Data System (ADS)

Lapalme, Ervig

2005-07-01

This thesis is devoted to biomagnetic source localization using magnetoencephalography. This problem is known to have an infinite number of solutions. So methods are required to take into account anatomical and functional information on the solution. The work presented in this thesis uses the maximum entropy on the mean method to constrain the solution. This method originates from statistical mechanics and information theory. This thesis is divided into two main parts containing three chapters each. The first part reviews the magnetoencephalographic inverse problem: the theory needed to understand its context and the hypotheses for simplifying the problem. In the last chapter of this first part, the maximum entropy on the mean method is presented: its origins are explained and also how it is applied to our problem. The second part is the original work of this thesis presenting three articles; one of them already published and two others submitted for publication. In the first article, a biomagnetic source model is developed and applied in a theoretical con text but still demonstrating the efficiency of the method. In the second article, we go one step further towards a realistic modelization of the cerebral activation. The main priors are estimated using the magnetoencephalographic data. This method proved to be very efficient in realistic simulations. In the third article, the previous method is extended to deal with time signals thus exploiting the excellent time resolution offered by magnetoencephalography. Compared with our previous work, the temporal method is applied to real magnetoencephalographic data coming from a somatotopy experience and results agree with previous physiological knowledge about this kind of cognitive process.

Evaluative studies in nuclear medicine research: positron computed tomography assessment. Final report, January 1, 1982-December 31, 1982

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

Potchen, E.J.; Harris, G.I.; Gift, D.A. Reinhard, D.K.

Results are reported of the final phase of the study effort generally titled Evaluative Studies in Nuclear Medicine Research. The previous work is reviewed and extended to an assessment providing perspectives on medical applications of positron emission tomographic (PET) systems, their technological context, and the related economic and marketing environment. Methodologies developed and used in earlier phases of the study were continued, but specifically extended to include solicitation of opinion from commercial organizations deemed to be potential developers, manufacturers and marketers of PET systems. Several factors which influence the demand for clinical uses of PET are evaluated and discussed. Themore » recent Federal funding of applied research with PET systems is found to be a necessary and encouraging event toward a determination that PET either is a powerful research tool limited to research, or whether it also presents major clinical utility. A comprehensive, updated bibliography of current literature related to the development, applications and economic considerations of PET technology is appended.« less

Quaternionic (super) twistors extensions and general superspaces

NASA Astrophysics Data System (ADS)

Cirilo-Lombardo, Diego Julio; Pervushin, Victor N.

2017-09-01

In a attempt to treat a supergravity as a tensor representation, the four-dimensional N-extended quaternionic superspaces are constructed from the (diffeomorphyc) graded extension of the ordinary Penrose-twistor formulation, performed in a previous work of the authors [D. J. Cirilo-Lombardo and V. N. Pervushin, Int. J. Geom. Methods Mod. Phys., doi: http://dx.doi.org/10.1142/S0219887816501139.], with N = p + k. These quaternionic superspaces have 4 + k(N - k) even-quaternionic coordinates and 4N odd-quaternionic coordinates, where each coordinate is a quaternion composed by four ℂ-fields (bosons and fermions respectively). The fields content as the dimensionality (even and odd sectors) of these superspaces are given and exemplified by selected physical cases. In this case, the number of fields of the supergravity is determined by the number of components of the tensor representation of the four-dimensional N-extended quaternionic superspaces. The role of tensorial central charges for any N even USp(N) = Sp(N, ℍℂ) ∩ U(N, ℍℂ) is elucidated from this theoretical context.

Ontology Design Patterns as Interfaces (invited)

NASA Astrophysics Data System (ADS)

Janowicz, K.

2015-12-01

In recent years ontology design patterns (ODP) have gained popularity among knowledge engineers. ODPs are modular but self-contained building blocks that are reusable and extendible. They minimize the amount of ontological commitments and thereby are easier to integrate than large monolithic ontologies. Typically, patterns are not directly used to annotate data or to model certain domain problems but are combined and extended to form data and purpose-driven local ontologies that serve the needs of specific applications or communities. By relying on a common set of patterns these local ontologies can be aligned to improve interoperability and enable federated queries without enforcing a top-down model of the domain. In previous work, we introduced ontological views as layer on top of ontology design patterns to ease the reuse, combination, and integration of patterns. While the literature distinguishes multiple types of patterns, e.g., content patterns or logical patterns, we propose to use them as interfaces here to guide the development of ontology-driven systems.

The Publicly Available Prebiotic Interstellar Molecular Survey (primos): Expanding Spectroscopic Characterizations, Extending to New Sources, and Adding to the Known Molecular Inventory

NASA Astrophysics Data System (ADS)

McGuire, Brett A.; Carroll, P. Brandon; Corby, Joanna F.; Loomis, Ryan A.; Blake, Geoffrey A.; Hollis, Jan M.; Lovas, Frank J.; Jewell, Philip R.; Remijan, Anthony J.

2013-06-01

The publicly available Green Bank Telescope PRebiotic Interstellar MOlecular Survey (PRIMOS) conducted towards Sgr B2(N) provides high resolution, high-sensitivity observations with near-continuous frequency coverage from ˜300 MHz - 50 GHz. Of the eleven new molecular detections in the last year, five (45%) are a direct result of the PRIMOS observations. Further, these observations have recently been used to detect the predicted, but previously unobserved, J = 1-0 and J=2-1 transitions of the newly detected l-C_3H^+ ion. Here, we discuss the analysis of these transitions, as well as recent work to extend the PRIMOS observations to three new regions of interest: VY Canis Majoris, IRC+10216, and NGC 2023. Finally, we highlight the utility of cm-wave surveys in new molecular detections, as well as the value of publicly-available surveys in the approaching era of data-enabled, analysis-limited astrochemistry.

Modelling the influence of sensory dynamics on linear and nonlinear driver steering control

NASA Astrophysics Data System (ADS)

Nash, C. J.; Cole, D. J.

2018-05-01

A recent review of the literature has indicated that sensory dynamics play an important role in the driver-vehicle steering task, motivating the design of a new driver model incorporating human sensory systems. This paper presents a full derivation of the linear driver model developed in previous work, and extends the model to control a vehicle with nonlinear tyres. Various nonlinear controllers and state estimators are compared with different approximations of the true system dynamics. The model simulation time is found to increase significantly with the complexity of the controller and state estimator. In general the more complex controllers perform best, although with certain vehicle and tyre models linearised controllers perform as well as a full nonlinear optimisation. Various extended Kalman filters give similar results, although the driver's sensory dynamics reduce control performance compared with full state feedback. The new model could be used to design vehicle systems which interact more naturally and safely with a human driver.

Integrating the automatic and the controlled: Strategies in Semantic Priming in an Attractor Network with Latching Dynamics

PubMed Central

Lerner, Itamar; Bentin, Shlomo; Shriki, Oren

2014-01-01

Semantic priming has long been recognized to reflect, along with automatic semantic mechanisms, the contribution of controlled strategies. However, previous theories of controlled priming were mostly qualitative, lacking common grounds with modern mathematical models of automatic priming based on neural networks. Recently, we have introduced a novel attractor network model of automatic semantic priming with latching dynamics. Here, we extend this work to show how the same model can also account for important findings regarding controlled processes. Assuming the rate of semantic transitions in the network can be adapted using simple reinforcement learning, we show how basic findings attributed to controlled processes in priming can be achieved, including their dependency on stimulus onset asynchrony and relatedness proportion and their unique effect on associative, category-exemplar, mediated and backward prime-target relations. We discuss how our mechanism relates to the classic expectancy theory and how it can be further extended in future developments of the model. PMID:24890261

First experimental evidence of hydrodynamic tunneling of ultra-relativistic protons in extended solid copper target at the CERN HiRadMat facility

NASA Astrophysics Data System (ADS)

Schmidt, R.; Blanco Sancho, J.; Burkart, F.; Grenier, D.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.

2014-08-01

A novel experiment has been performed at the CERN HiRadMat test facility to study the impact of the 440 GeV proton beam generated by the Super Proton Synchrotron on extended solid copper cylindrical targets. Substantial hydrodynamic tunneling of the protons in the target material has been observed that leads to significant lengthening of the projectile range, which confirms our previous theoretical predictions [N. A. Tahir et al., Phys. Rev. Spec. Top.-Accel. Beams 15, 051003 (2012)]. Simulation results show very good agreement with the experimental measurements. These results have very important implications on the machine protection design for powerful machines like the Large Hadron Collider (LHC), the future High Luminosity LHC, and the proposed huge 80 km circumference Future Circular Collider, which is currently being discussed at CERN. Another very interesting outcome of this work is that one may also study the field of High Energy Density Physics at this test facility.

Pair correlation functions for identifying spatial correlation in discrete domains

NASA Astrophysics Data System (ADS)

Gavagnin, Enrico; Owen, Jennifer P.; Yates, Christian A.

2018-06-01

Identifying and quantifying spatial correlation are important aspects of studying the collective behavior of multiagent systems. Pair correlation functions (PCFs) are powerful statistical tools that can provide qualitative and quantitative information about correlation between pairs of agents. Despite the numerous PCFs defined for off-lattice domains, only a few recent studies have considered a PCF for discrete domains. Our work extends the study of spatial correlation in discrete domains by defining a new set of PCFs using two natural and intuitive definitions of distance for a square lattice: the taxicab and uniform metric. We show how these PCFs improve upon previous attempts and compare between the quantitative data acquired. We also extend our definitions of the PCF to other types of regular tessellation that have not been studied before, including hexagonal, triangular, and cuboidal. Finally, we provide a comprehensive PCF for any tessellation and metric, allowing investigation of spatial correlation in irregular lattices for which recognizing correlation is less intuitive.

A quantum perturbative pair distribution for determining interatomic potentials from extended x-ray absorption spectroscopy

NASA Astrophysics Data System (ADS)

Piazza, F.

2002-11-01

In this paper we develop a technique for determining interatomic potentials in materials in the quantum regime from single-shell extended x-ray absorption spectroscopy (EXAFS) spectra. We introduce a pair distribution function, based on ordinary quantum time-independent perturbation theory. In the proposed scheme, the model potential parameters enter the distribution through a fourth-order Taylor expansion of the potential, and are directly refined in the fit of the model signal to the experimental spectrum. We discuss in general the validity of our theoretical framework, namely the quantum regime and perturbative treatment, and work out a simple tool for monitoring the sensitivity of our theory in determining lattice anharmonicities based on the statistical F-test. As an example, we apply our formalism to an EXAFS spectrum at the Ag K edge of AgI at T = 77 K. We determine the Ag-I potential parameters and find good agreement with previous studies.

Contaminant transport in wetland flows with bulk degradation and bed absorption

NASA Astrophysics Data System (ADS)

Wang, Ping; Chen, G. Q.

2017-09-01

Ecological degradation and absorption are ubiquitous and exert considerable influence on the contaminant transport in natural and constructed wetland flows. It creates an increased demand on models to accurately characterize the spatial concentration distribution of the transport process. This work extends a method of spatial concentration moments by considering the non-uniform longitudinal solute displacements along the vertical direction, and analytically determines the spatial concentration distribution in the very initial stage since source release with effects of bulk degradation and bed absorption. The present method is demonstrated to bear a more accurate prediction especially in the initial stage through convergence analysis of Hermite polynomials. Results reveal that contaminant cloud shows to be more contracted and reformed by bed absorption with increasing damping factor of wetland flows. Tremendous vertical concentration variation especially in the downstream of the contaminant cloud remains great even at asymptotic large times. Spatial concentration evolution by the extended method other than the mean by previous studies is potential for various implements associated with contaminant transport with strict environmental standards.

Retrieval of total water vapour in the Arctic using microwave humidity sounders

NASA Astrophysics Data System (ADS)

Cristian Scarlat, Raul; Melsheimer, Christian; Heygster, Georg

2018-04-01

Quantitative retrievals of atmospheric water vapour in the Arctic present numerous challenges because of the particular climate characteristics of this area. Here, we attempt to build upon the work of Melsheimer and Heygster (2008) to retrieve total atmospheric water vapour (TWV) in the Arctic from satellite microwave radiometers. While the above-mentioned algorithm deals primarily with the ice-covered central Arctic, with this work we aim to extend the coverage to partially ice-covered and ice-free areas. By using modelled values for the microwave emissivity of the ice-free sea surface, we develop two sub-algorithms using different sets of channels that deal solely with open-ocean areas. The new algorithm extends the spatial coverage of the retrieval throughout the year but especially in the warmer months when higher TWV values are frequent. The high TWV measurements over both sea-ice and open-water surfaces are, however, connected to larger uncertainties as the retrieval values are close to the instrument saturation limits.This approach allows us to apply the algorithm to regions where previously no data were available and ensures a more consistent physical analysis of the satellite measurements by taking into account the contribution of the surface emissivity to the measured signal.

New Fe i Level Energies and Line Identifications from Stellar Spectra. II. Initial Results from New Ultraviolet Spectra of Metal-poor Stars

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

Peterson, Ruth C.; Kurucz, Robert L.; Ayres, Thomas R., E-mail: peterson@ucolick.org

2017-04-01

The Fe i spectrum is critical to many areas of astrophysics, yet many of the high-lying levels remain uncharacterized. To remedy this deficiency, Peterson and Kurucz identified Fe i lines in archival ultraviolet and optical spectra of metal-poor stars, whose warm temperatures favor moderate Fe i excitation. Sixty-five new levels were recovered, with 1500 detectable lines, including several bound levels in the ionization continuum of Fe i. Here, we extend the previous work by identifying 59 additional levels, with 1400 detectable lines, by incorporating new high-resolution UV spectra of warm metal-poor stars recently obtained by the Hubble Space Telescope Imagingmore » Spectrograph. We provide gf values for these transitions, both computed as well as adjusted to fit the stellar spectra. We also expand our spectral calculations to the infrared, confirming three levels by matching high-quality spectra of the Sun and two cool stars in the H -band. The predicted gf values suggest that an additional 3700 Fe i lines should be detectable in existing solar infrared spectra. Extending the empirical line identification work to the infrared would help confirm additional Fe i levels, as would new high-resolution UV spectra of metal-poor turnoff stars below 1900 Å.« less

Aerodynamic Shape Optimization of Complex Aircraft Configurations via an Adjoint Formulation

NASA Technical Reports Server (NTRS)

Reuther, James; Jameson, Antony; Farmer, James; Martinelli, Luigi; Saunders, David

1996-01-01

This work describes the implementation of optimization techniques based on control theory for complex aircraft configurations. Here control theory is employed to derive the adjoint differential equations, the solution of which allows for a drastic reduction in computational costs over previous design methods (13, 12, 43, 38). In our earlier studies (19, 20, 22, 23, 39, 25, 40, 41, 42) it was shown that this method could be used to devise effective optimization procedures for airfoils, wings and wing-bodies subject to either analytic or arbitrary meshes. Design formulations for both potential flows and flows governed by the Euler equations have been demonstrated, showing that such methods can be devised for various governing equations (39, 25). In our most recent works (40, 42) the method was extended to treat wing-body configurations with a large number of mesh points, verifying that significant computational savings can be gained for practical design problems. In this paper the method is extended for the Euler equations to treat complete aircraft configurations via a new multiblock implementation. New elements include a multiblock-multigrid flow solver, a multiblock-multigrid adjoint solver, and a multiblock mesh perturbation scheme. Two design examples are presented in which the new method is used for the wing redesign of a transonic business jet.

Virtual milk for modelling and simulation of dairy processes.

PubMed

Munir, M T; Zhang, Y; Yu, W; Wilson, D I; Young, B R

2016-05-01

The modeling of dairy processing using a generic process simulator suffers from shortcomings, given that many simulators do not contain milk components in their component libraries. Recently, pseudo-milk components for a commercial process simulator were proposed for simulation and the current work extends this pseudo-milk concept by studying the effect of both total milk solids and temperature on key physical properties such as thermal conductivity, density, viscosity, and heat capacity. This paper also uses expanded fluid and power law models to predict milk viscosity over the temperature range from 4 to 75°C and develops a succinct regressed model for heat capacity as a function of temperature and fat composition. The pseudo-milk was validated by comparing the simulated and actual values of the physical properties of milk. The milk thermal conductivity, density, viscosity, and heat capacity showed differences of less than 2, 4, 3, and 1.5%, respectively, between the simulated results and actual values. This work extends the capabilities of the previously proposed pseudo-milk and of a process simulator to model dairy processes, processing different types of milk (e.g., whole milk, skim milk, and concentrated milk) with different intrinsic compositions, and to predict correct material and energy balances for dairy processes. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A Time Series Analysis of Cancer-Related Information Seeking: Hints From the Health Information National Trends Survey (HINTS) 2003-2014.

PubMed

Huerta, Timothy R; Walker, Daniel M; Johnson, Tyler; Ford, Eric W

2016-09-01

Recent technological changes, such as the growth of the Internet, have made cancer information widely available. However, it remains unknown whether changes in access have resulted in concomitant changes in information seeking behavior. Previous work explored the cancer information seeking behaviors of the general population using the 2003 Health Information National Trends Survey (HINTS). This article aims to reproduce, replicate, and extend that existing analysis using the original dataset and five additional iterations of HINTS (2007, 2011, 2012, 2013, 2014). This approach builds on the earlier work by quantifying the magnitude of change in information seeking behaviors. Bivariate comparison of the 2003 and 2014 data revealed very similar results; however, the multivariate model including all years of data indicated differences between the original and extended models: individuals age 65 and older were no longer less likely to seek cancer information than the 18-35 reference population, and Hispanics were also no longer less likely to be cancer information seekers. The results of our analysis indicate an overall shift in cancer information seeking behaviors and also illuminate the impact of increased Internet usage over the past decade, suggesting specific demographic groups that may benefit from cancer information seeking encouragement.

New Fe I Level Energies and Line Identifications from Stellar Spectra. II. Initial Results from New Ultraviolet Spectra of Metal-poor Stars

NASA Astrophysics Data System (ADS)

Peterson, Ruth C.; Kurucz, Robert L.; Ayres, Thomas R.

2017-04-01

The Fe I spectrum is critical to many areas of astrophysics, yet many of the high-lying levels remain uncharacterized. To remedy this deficiency, Peterson & Kurucz identified Fe I lines in archival ultraviolet and optical spectra of metal-poor stars, whose warm temperatures favor moderate Fe I excitation. Sixty-five new levels were recovered, with 1500 detectable lines, including several bound levels in the ionization continuum of Fe I. Here, we extend the previous work by identifying 59 additional levels, with 1400 detectable lines, by incorporating new high-resolution UV spectra of warm metal-poor stars recently obtained by the Hubble Space Telescope Imaging Spectrograph. We provide gf values for these transitions, both computed as well as adjusted to fit the stellar spectra. We also expand our spectral calculations to the infrared, confirming three levels by matching high-quality spectra of the Sun and two cool stars in the H-band. The predicted gf values suggest that an additional 3700 Fe I lines should be detectable in existing solar infrared spectra. Extending the empirical line identification work to the infrared would help confirm additional Fe I levels, as would new high-resolution UV spectra of metal-poor turnoff stars below 1900 Å.

Incidental threat during visuospatial working memory in adolescent anxiety: an emotional memory-guided saccade task.

PubMed

Mueller, Sven C; Shechner, Tomer; Rosen, Dana; Nelson, Eric E; Pine, Daniel S; Ernst, Monique

2015-04-01

Pediatric anxiety disorders are among the most common psychiatric mental illnesses in children and adolescents, and are associated with abnormal cognitive control in emotional, particularly threat, contexts. In a series of studies using eye movement saccade tasks, we reported anxiety-related alterations in the interplay of inhibitory control with incentives, or with emotional distractors. The present study extends these findings to working memory (WM), and queries the interaction of spatial WM with emotional stimuli in pediatric clinical anxiety. Participants were 33 children/adolescents diagnosed with an anxiety disorder, and 22 age-matched healthy comparison youths. Participants completed a novel eye movement task, an affective variant of the memory-guided saccade task. This task assessed the influence of incidental threat on spatial WM processes during high and low cognitive load. Healthy but not anxious children/adolescents showed slowed saccade latencies during incidental threat in low-load but not high-load WM conditions. No other group effects emerged on saccade latency or accuracy. The current data suggest a differential pattern of how emotion interacts with cognitive control in healthy youth relative to anxious youth. These findings extend data from inhibitory processes, reported previously, to spatial WM in pediatric anxiety. © 2015 Wiley Periodicals, Inc.

Production version of the extended NASA-Langley Vortex Lattice FORTRAN computer program. Volume 1: User's guide

NASA Technical Reports Server (NTRS)

Lamar, J. E.; Herbert, H. E.

1982-01-01

The latest production version, MARK IV, of the NASA-Langley vortex lattice computer program is summarized. All viable subcritical aerodynamic features of previous versions were retained. This version extends the previously documented program capabilities to four planforms, 400 panels, and enables the user to obtain vortex-flow aerodynamics on cambered planforms, flowfield properties off the configuration in attached flow, and planform longitudinal load distributions.

Physiological response to firefighting activities of various work cycles using extended duration and prototype SCBA.

PubMed

Kesler, Richard M; Ensari, Ipek; Bollaert, Rachel E; Motl, Robert W; Hsiao-Wecksler, Elizabeth T; Rosengren, Karl S; Fernhall, Bo; Smith, Denise L; Horn, Gavin P

2018-03-01

Firefighters' self-contained breathing apparatus (SCBA) protects the respiratory system during firefighting but increases the physiological burden. Extended duration SCBA (>30 min) have increased air supply, potentially increasing the duration of firefighting work cycles. To examine the effects of SCBA configuration and work cycle (length and rest), 30 firefighters completed seven trials using different SCBA and one or two bouts of simulated firefighting following work cycles common in the United States. Heart rate, core temperature, oxygen consumption, work output and self-reported perceptions were recorded during all activities. Varying SCBA resulted in few differences in these parameters. However, during a second bout, work output significantly declined while heart rates and core temperatures were elevated relative to a single bout. Thirty seven per cent of the subjects were unable to complete the second bout in at least one of the two-bout conditions. These firefighters had lower fitness and higher body mass than those who completed all assigned tasks. Practitioner Summary: The effects of extended duration SCBA and work/rest cycles on physiological parameters and work output have not been examined. Cylinder size had minimal effects, but extended work cycles with no rest resulted in increased physiological strain and decreased work output. This effect was more pronounced in firefighters with lower fitness.

Microflaring in Low-Lying Core Fields and Extended Coronal Heating in the Quiet Sun

NASA Technical Reports Server (NTRS)

Porter, Jason G.; Falconer, D. A.; Moore, Ronald L.

1999-01-01

We have previously reported analyses of Yohkoh SXT data examining the relationship between the heating of extended coronal loops (both within and stemming from active regions) and microflaring in core fields lying along neutral lines near their footpoints (J. G. Porter, D. A. Falconer, and R. L. Moore 1998, in Solar Jets and Coronal Plumes, ed. T. Guyenne, ESA SP-421, and references therein). We found a surprisingly poor correlation of intensity variations in the extended loops with individual microflares in the compact heated areas at their feet, despite considerable circumstancial evidence linking the heating processes in these regions. Now, a study of Fe XII image sequences from SOHO EIT show that similar associations of core field structures with the footpoints of very extended coronal features can be found in the quiet Sun. The morphology is consistent with the finding of Wang et al. (1997, ApJ 484, L75) that polar plumes are rooted at sites of mixed polarity in the magnetic network. We find that the upstairs/downstairs intensity variations often follow the trend, identified in the active region observations, of a weak correspondence. Apparently much of the coronal heating in the extended loops is driven by a type of core field magnetic activity that is "cooler" than the events having the coronal signature of microflares, i.e., activity that results in little heating within the core fields themselves. This work was funded by the Solar Physics Branch of NASA's Office of Space Science through the SR&T Program and the SEC Guest Investigator Program.

Search for Unique Organic Biomarkers in ALH84001

NASA Technical Reports Server (NTRS)

Zare, Richard N.

1999-01-01

Four goals were outlined for this project. These were: [1] to reproduce the measurement of polycyclic aromatic hydrocarbons (PAHS) in ALH84001 with both a higher spatial resolution and sensitivity than has been previously reported; [2] to extend such measurements to include other members of the Martian SNC (Shergotties, Nahklites, and Chassigny) meteorite clan, in particular the Antarctic Martian meteorite EETA79001; [3] to address issues of potential organic contamination, because at present very little is known about the effect of terrestrial weathering in the Antarctic environment as it pertains to perturbing an indigenous organic distribution within a meteoritic matrix; and [4] to diversify the range of organic compounds studied to include species that can serve as unique biological markers - "molecular fossils" - derived from once living organisms. In order to achieve this, three specific goals were outlined for the funding period 06/01/97 to 02/28/98. They were: [1] to investigate the effects of terrestrial weathering and organic contamination of meteoritic samples collected from Antarctica; [2] to reproduce and extend upon the measurements of PAHs in ALH84001 with the aim of establishing or refuting the indigeneity of these species; and [3] to extend the analysis of organic compounds in ALH84001 and EETA79001 to address compounds that are considered to be more biologically relevant than PAHS. All three were successfully accomplished, as detailed in the previous performance report. In brief, however, the results achieved were to establish that the PAHs found in ALH84001 were indigenous and not due to contamination, and to determine that a novel and sensitive technique in meteoritic work, capillary zone electrophoresis (CE), could indeed detect amino acids, a potential class of biomarker.

Evaluating Hierarchical Structure in Music Annotations

PubMed Central

McFee, Brian; Nieto, Oriol; Farbood, Morwaread M.; Bello, Juan Pablo

2017-01-01

Music exhibits structure at multiple scales, ranging from motifs to large-scale functional components. When inferring the structure of a piece, different listeners may attend to different temporal scales, which can result in disagreements when they describe the same piece. In the field of music informatics research (MIR), it is common to use corpora annotated with structural boundaries at different levels. By quantifying disagreements between multiple annotators, previous research has yielded several insights relevant to the study of music cognition. First, annotators tend to agree when structural boundaries are ambiguous. Second, this ambiguity seems to depend on musical features, time scale, and genre. Furthermore, it is possible to tune current annotation evaluation metrics to better align with these perceptual differences. However, previous work has not directly analyzed the effects of hierarchical structure because the existing methods for comparing structural annotations are designed for “flat” descriptions, and do not readily generalize to hierarchical annotations. In this paper, we extend and generalize previous work on the evaluation of hierarchical descriptions of musical structure. We derive an evaluation metric which can compare hierarchical annotations holistically across multiple levels. sing this metric, we investigate inter-annotator agreement on the multilevel annotations of two different music corpora, investigate the influence of acoustic properties on hierarchical annotations, and evaluate existing hierarchical segmentation algorithms against the distribution of inter-annotator agreement. PMID:28824514

Failed reciprocity in close social relationships and health: findings from the Whitehall II study.

PubMed

Chandola, Tarani; Marmot, Michael; Siegrist, Johannes

2007-10-01

To extend the model of effort-reward imbalance at work to close and more general social relationships and test the associations with different measures of health. Lack of reciprocity at work is associated with poorer health in a number of studies. However, few studies have analysed the effect of nonreciprocity in other kinds of social relationships on health. The Whitehall II Study is an ongoing prospective study of British civil servants (n=10308 at baseline in 1985-88). Cross-sectional data from the latest phase (7, n=6944 in 2002-04) were used in the analyses. The main exposure was a questionnaire measuring nonreciprocal social relations in partnership, parent-children, and general trusting relationships. Health measures included the SF-36 mental and physical component scores, General Health Questionnaire-30 depression subscale, Jenkins' Sleep disturbance questionnaire, and the Rose Angina questionnaire. Logistic and linear regression models were analysed, adjusted for potential confounders, and mediators of the association. Lack of reciprocity is associated with all measures of poorer health. This association attenuates after adjustment for previous health and additional confounders and mediators but remains significant in a majority of models. Negative social support from a close person is independently associated with reduced health, but adjusting for this effect does not eliminate the association of nonreciprocity with poor health. The effort-reward imbalance at work model has been extended to close and more general social relationships. Lack of reciprocity in partnership, parent-children and general trusting relationships is associated with poorer health.

High Throughput System for Plant Height and Hyperspectral Measurement

NASA Astrophysics Data System (ADS)

Zhao, H.; Xu, L.; Jiang, H.; Shi, S.; Chen, D.

2018-04-01

Hyperspectral and three-dimensional measurement can obtain the intrinsic physicochemical properties and external geometrical characteristics of objects, respectively. Currently, a variety of sensors are integrated into a system to collect spectral and morphological information in agriculture. However, previous experiments were usually performed with several commercial devices on a single platform. Inadequate registration and synchronization among instruments often resulted in mismatch between spectral and 3D information of the same target. And narrow field of view (FOV) extends the working hours in farms. Therefore, we propose a high throughput prototype that combines stereo vision and grating dispersion to simultaneously acquire hyperspectral and 3D information.

Stiffness and Damping Coefficient Estimation of Compliant Surface Gas Bearings for Oil-Free Turbomachinery

NASA Technical Reports Server (NTRS)

Della-Corte, Christopher

2012-01-01

Foil gas bearings are a key technology in many commercial and emerging oilfree turbomachinery systems. These bearings are nonlinear and have been difficult to analytically model in terms of performance characteristics such as load capacity, power loss, stiffness, and damping. Previous investigations led to an empirically derived method to estimate load capacity. This method has been a valuable tool in system development. The current work extends this tool concept to include rules for stiffness and damping coefficient estimation. It is expected that these rules will further accelerate the development and deployment of advanced oil-free machines operating on foil gas bearings.

Multiple core-hole formation by free-electron laser radiation in molecular nitrogen

NASA Astrophysics Data System (ADS)

Banks, H. I. B.; Little, D. A.; Emmanouilidou, A.

2018-05-01

We investigate the formation of multiple-core-hole states of molecular nitrogen interacting with a free-electron laser pulse. In previous work, we obtained bound and continuum molecular orbitals in the single-center expansion scheme and used these orbitals to calculate photo-ionization and auger decay rates. We extend our formulation to track the proportion of the population that accesses single-site versus two-site double-core-hole (TSDCH) states, before the formation of the final atomic ions. We investigate the pulse parameters that favor the formation of the single-site and TSDCH as well as triple-core-hole states for 525 and 1100 eV photons.

Cryogenic IR spectroscopy combined with ion mobility spectrometry for the analysis of human milk oligosaccharides.

PubMed

Khanal, Neelam; Masellis, Chiara; Kamrath, Michael Z; Clemmer, David E; Rizzo, Thomas R

2018-04-16

We report here our combination of cryogenic, messenger-tagging, infrared (IR) spectroscopy with ion mobility spectrometry (IMS) and mass spectrometry (MS) as a way to identify and analyze a set of human milk oligosaccharides (HMOs) ranging from trisaccharides to hexasaccharides. The added dimension of IR spectroscopy provides a diagnostic fingerprint in the OH and NH stretching region, which is crucial to identify these oligosaccharides, which are difficult to distinguish by IMS alone. These results extend our previous work in demonstrating the generality of this combined approach for distinguishing subtly different structural and regioisomers of glycans of biologically relevant size.

Detecting duplicate biological entities using Shortest Path Edit Distance.

PubMed

Rudniy, Alex; Song, Min; Geller, James

2010-01-01

Duplicate entity detection in biological data is an important research task. In this paper, we propose a novel and context-sensitive Shortest Path Edit Distance (SPED) extending and supplementing our previous work on Markov Random Field-based Edit Distance (MRFED). SPED transforms the edit distance computational problem to the calculation of the shortest path among two selected vertices of a graph. We produce several modifications of SPED by applying Levenshtein, arithmetic mean, histogram difference and TFIDF techniques to solve subtasks. We compare SPED performance to other well-known distance algorithms for biological entity matching. The experimental results show that SPED produces competitive outcomes.

The role of fluctuation-induced transport in a toroidal plasma with strong radial electric fields

NASA Technical Reports Server (NTRS)

Roth, J. R.; Krawczonek, W. M.; Powers, E. J.; Hong, J. Y.; Kim, Y. C.

1981-01-01

Previous work employing digitally implemented spectral analysis techniques is extended to demonstrate that radial fluctuation-induced transport is the dominant ion transport mechanism in an electric field dominated toroidal plasma. Such transport can be made to occur against a density gradient, and hence may have a very beneficial effect on confinement in toroidal plasmas of fusion interest. It is shown that Bohm or classical diffusion down a density gradient, the collisional Pedersen-current mechanism, and the collisionless electric field gradient mechanism described by Cole (1976) all played a minor role, if any, in the radial transport of this plasma.

Prompting one low-fat, high-fiber selection in a fast-food restaurant.

PubMed

Wagner, J L; Winett, R A

1988-01-01

Evidence increasingly links a high-fat, low-fiber diet to coronary heart disease and certain site cancers, indicating a need for large-scale dietary change. Studies showing the effectiveness of particular procedures in specific settings are important at this point. The present study, using an A-B-A-B design and sales data from computerized cash registers, replicated and extended previous work by showing that inexpensive prompts (i.e., signs and fliers) in a national fast-food restaurant could increase the sales of salads, a low-fat, high-fiber menu selection. Suggestions also are made pertinent to more widespread use of the procedures.

Impact of infrasound atmospheric noise on gravity detectors used for astrophysical and geophysical applications

NASA Astrophysics Data System (ADS)

Fiorucci, Donatella; Harms, Jan; Barsuglia, Matteo; Fiori, Irene; Paoletti, Federico

2018-03-01

Density changes in the atmosphere produce a fluctuating gravity field that affects gravity strainmeters or gravity gradiometers used for the detection of gravitational waves and for geophysical applications. This work addresses the impact of the atmospheric local gravity noise on such detectors, extending previous analyses. In particular we present the effect introduced by the building housing the detectors, and we analyze local gravity-noise suppression by constructing the detector underground. We present also new sound spectra and correlation measurements. The results obtained are important for the design of future gravitational-wave detectors and gravity gradiometers used to detect prompt gravity perturbations from earthquakes.

Evolution of Structure and Composition in Saturn's Rings Due to Ballistic Transport of Micrometeoroid Impact Ejecta

NASA Astrophysics Data System (ADS)

Estrada, P. R.; Durisen, R. H.; Cuzzi, J. N.

2014-04-01

We introduce improved numerical techniques for simulating the structural and compositional evolution of planetary rings due to micrometeoroid bombardment and subsequent ballistic transport of impact ejecta. Our current, robust code, which is based on the original structural code of [1] and on the pollution transport code of [3], is capable of modeling structural changes and pollution transport simultaneously over long times on both local and global scales. We provide demonstrative simulations to compare with, and extend upon previous work, as well as examples of how ballistic transport can maintain the observed structure in Saturn's rings using available Cassini occultation optical depth data.

Quantum dynamical simulation of photoinduced electron transfer processes in dye-semiconductor systems: theory and application to coumarin 343 at TiO₂.

PubMed

Li, Jingrui; Kondov, Ivan; Wang, Haobin; Thoss, Michael

2015-04-10

A recently developed methodology to simulate photoinduced electron transfer processes at dye-semiconductor interfaces is outlined. The methodology employs a first-principles-based model Hamiltonian and accurate quantum dynamics simulations using the multilayer multiconfiguration time-dependent Hartree approach. This method is applied to study electron injection in the dye-semiconductor system coumarin 343-TiO2. Specifically, the influence of electronic-vibrational coupling is analyzed. Extending previous work, we consider the influence of Dushinsky rotation of the normal modes as well as anharmonicities of the potential energy surfaces on the electron transfer dynamics.

Comparison of Low-Energy Lunar Transfer Trajectories to Invariant Manifolds

NASA Technical Reports Server (NTRS)

Anderson, Rodney L.; Parker, Jeffrey S.

2011-01-01

In this study, transfer trajectories from the Earth to the Moon that encounter the Moon at various flight path angles are examined, and lunar approach trajectories are compared to the invariant manifolds of selected unstable orbits in the circular restricted three-body problem. Previous work focused on lunar impact and landing trajectories encountering the Moon normal to the surface, and this research extends the problem with different flight path angles in three dimensions. The lunar landing geometry for a range of Jacobi constants are computed, and approaches to the Moon via invariant manifolds from unstable orbits are analyzed for different energy levels.

Owning the program technical baseline for future space systems acquisition: program technical baseline tracking tool

NASA Astrophysics Data System (ADS)

Nguyen, Tien M.; Guillen, Andy T.; Hant, James J.; Kizer, Justin R.; Min, Inki A.; Siedlak, Dennis J. L.; Yoh, James

2017-05-01

The U.S. Air Force (USAF) has recognized the needs for owning the program and technical knowledge within the Air Force concerning the systems being acquired to ensure success. This paper extends the previous work done by the authors [1-2] on the "Resilient Program Technical Baseline Framework for Future Space Systems" and "Portfolio Decision Support Tool (PDST)" to the development and implementation of the Program and Technical Baseline (PTB) Tracking Tool (PTBTL) for the DOD acquisition life cycle. The paper describes the "simplified" PTB tracking model with a focus on the preaward phases and discusses how to implement this model in PDST.

Water walking - an evolution of water surface skipping

NASA Astrophysics Data System (ADS)

Hurd, Randy; Belden, Jesse; Jandron, Michael; Bower, Allan; Holekamp, Sean; Truscott, Tadd

2017-11-01

Previous work has shown that elastomeric spheres skip more easily than disk-shaped stones. This is due to increased lift stemming from sphere deformation, which provides an increased cross-sectional area and favorable attack angle upon impact. We extend lift models developed for individual impacts to long-range multiple impact events and compare the estimates to experimental results, which show good agreement. Additionally, a surprising new mode of skipping is observed that resembles water-walking, wherein a quickly rotating sphere produces small successive impacts allowing it to move parallel to the water surface. The dynamics of this new multiple skip behavior are rationalized analytically and tested experimentally.

Directional x-ray dark-field imaging of strongly ordered systems

NASA Astrophysics Data System (ADS)

Jensen, Torben Haugaard; Bech, Martin; Zanette, Irene; Weitkamp, Timm; David, Christian; Deyhle, Hans; Rutishauser, Simon; Reznikova, Elena; Mohr, Jürgen; Feidenhans'L, Robert; Pfeiffer, Franz

2010-12-01

Recently a novel grating based x-ray imaging approach called directional x-ray dark-field imaging was introduced. Directional x-ray dark-field imaging yields information about the local texture of structures smaller than the pixel size of the imaging system. In this work we extend the theoretical description and data processing schemes for directional dark-field imaging to strongly scattering systems, which could not be described previously. We develop a simple scattering model to account for these recent observations and subsequently demonstrate the model using experimental data. The experimental data includes directional dark-field images of polypropylene fibers and a human tooth slice.

IRAS observations of chromospherically active dwarf stars

NASA Technical Reports Server (NTRS)

Tsikoudi, Vassiliki

1989-01-01

Far-infrared observations of chromospherically active, spotted, and plage stars in the dF7-dk7 spectral range are examined. Most (75 percent) of the stars have detectable 12-micron fluxes, and 50 percent of them have 25-micron emission. The 12-micron luminosity, L(12), is found to be in the range of 1.5-13 x 10 to the 30th ergs/s and to comprise only 0.2-0.5 percent of the star's total luminosity, L(bol). The present work extends to earlier spectral types and higher stellar luminosities the L(12) vs L(bol) relationship noted previously for late-type active dwarfs (K5-M5).

A fully coupled 3D transport model in SPH for multi-species reaction-diffusion systems

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

Adami, Stefan; Hu, X. Y.; Adams, N. A.

2011-08-23

Abstract—In this paper we present a fully generalized transport model for multiple species in complex two and threedimensional geometries. Based on previous work [1] we have extended our interfacial reaction-diffusion model to handle arbitrary numbers of species allowing for coupled reaction models. Each species is tracked independently and we consider different physics of a species with respect to the bulk phases in contact. We use our SPH model to simulate the reaction-diffusion problem on a pore-scale level of a solid oxide fuel cell (SOFC) with special emphasize on the effect of surface diffusion.

Serial dependence in the perception of attractiveness.

PubMed

Xia, Ye; Leib, Allison Yamanashi; Whitney, David

2016-12-01

The perception of attractiveness is essential for choices of food, object, and mate preference. Like perception of other visual features, perception of attractiveness is stable despite constant changes of image properties due to factors like occlusion, visual noise, and eye movements. Recent results demonstrate that perception of low-level stimulus features and even more complex attributes like human identity are biased towards recent percepts. This effect is often called serial dependence. Some recent studies have suggested that serial dependence also exists for perceived facial attractiveness, though there is also concern that the reported effects are due to response bias. Here we used an attractiveness-rating task to test the existence of serial dependence in perceived facial attractiveness. Our results demonstrate that perceived face attractiveness was pulled by the attractiveness level of facial images encountered up to 6 s prior. This effect was not due to response bias and did not rely on the previous motor response. This perceptual pull increased as the difference in attractiveness between previous and current stimuli increased. Our results reconcile previously conflicting findings and extend previous work, demonstrating that sequential dependence in perception operates across different levels of visual analysis, even at the highest levels of perceptual interpretation.

Kinematic activity of gray wolf (Canis lupus) sperm in different extenders, added before or after centrifugation.

PubMed

Christensen, Bruce W; Asa, Cheryl S; Wang, Chong; Bauman, Karen; Agnew, Mary K; Lorton, Steven P; Callahan, Margaret

2013-04-01

We evaluated two approaches to improving in vitro wolf sperm survival. Both approaches aimed to reduce the exposure of sperm to prostatic fluid resulting from electroejaculation: (1) use of extender formulations recently developed for the domestic dog (the most closely related domestic species); and (2) dilution of ejaculate shortly after semen collection. Three commercial extenders were compared with the TRIS-based extender we had previously used. We also compared the effects on motility of adding extender immediately after collection to our previous protocol in which extender was added after centrifugation. Both subjective and objective (computer-assisted semen analysis program) kinematic measurements were made. Relatively minor differences were noted (and not in total or progressive motility) between the centrifugation protocols. Two of the commercial extenders resulted in significant improvement in motility over the TRIS-based extender and one of the other commercial extenders at 8 hours after collection (mean ± SEM; total motility was 68.3 ± 4.0% and 70.0 ± 4.0% compared with 53.3 ± 4.0% and 55.0 ± 4.0%, respectively; progressive motility 58.6 ± 5.4% and 57.1 ± 5.4% compared with 32.8 ± 5.4% and 39.3 ± 5.4%; P < 0.05). We inferred that components in two of the commercial dog extenders might provide more protection for wolf sperm, prolonging their motility. Copyright © 2013 Elsevier Inc. All rights reserved.

Personality Development at Work: Workplace Conditions, Personality Changes, and the Corresponsive Principle.

PubMed

Le, Kimdy; Donnellan, M Brent; Conger, Rand

2014-02-01

Investigations concerning adult personality development have increasingly focused on factors that are associated with apparent personality trait changes. The current study contributes to this literature by replicating and extending previous research concerning personality trait development in young adulthood and perceptions of workplace conditions. Analyses were based on up to 442 individuals who participated in the ongoing Family Transitions Project (e.g., Conger & Conger, 2002). The current analyses included personality trait data from 1994 and 2003, high school grades and socioeconomic status indicators from 1994, and reports about work conditions in 2001, 2003, and 2005. Personality attributes were prospectively associated with work conditions and income. Findings also support the corresponsive principle of personality development (e.g., Roberts, Caspi, & Moffitt, 2003): Traits that were prospectively associated with particular workplace conditions often seemed to be accentuated by those conditions. Personality traits are prospectively associated with perceptions of the workplace. Workplace conditions are also associated with trait development. © 2013 Wiley Periodicals, Inc.

Combining dispositions and evaluations of vocation and job to account for counterproductive work behavior in adolescent job apprentices.

PubMed

Marcus, Bernd; Wagner, Uwe

2007-04-01

In the present research, we investigated the joint impact of selected antecedents of counterproductive work behavior (CWB). A sample of German apprentices reported on their CWB and completed measures of situational evaluations (vocational preference, level and constructiveness of job satisfaction) believed to trigger CWB and of dispositional motivators (measured by integrity test subscales) and controls (self-control and another subset of integrity scales) of CWB. All predictors investigated showed the expected bivariate relationships with CWB. Multivariate analyses revealed that the triggering effect of an unfavorable vocational choice on CWB was fully mediated by job satisfaction. When predictors were aggregated, a composite of dispositional control variables had the largest effect on CWB and moderated the effects of motivational dispositions and situational evaluations. These results extend the knowledge on antecedents of CWB by investigating previously overlooked variables and samples and partially replicate recent findings on the joint impact of dispositions and work-related evaluations on CWB. Copyright (c) 2007 APA, all rights reserved.

Personality Development at Work: Workplace Conditions, Personality Changes, and the Corresponsive Principle

PubMed Central

Le, Kimdy; Donnellan, M. Brent; Conger, Rand

2013-01-01

Objective Investigations concerning adult personality development have increasingly focused on factors that are associated with apparent personality trait changes. The current study contributes to this literature by replicating and extending previous research concerning personality trait development in young adulthood and perceptions of workplace conditions. Method Analyses were based on up to 442 individuals who participated in the ongoing Family Transitions Project (e.g., Conger & Conger, 2002). The current analyses included personality trait data from 1994 and 2003, high-school grades and SES indicators from 1994, and reports about work conditions in 2001, 2003, and 2005. Results Personality attributes were prospectively associated with work conditions and income. Findings also support the corresponsive principle of personality development (e.g. Roberts, Caspi, & Moffitt, 2003): Traits that were prospectively associated with particular workplace conditions often seemed to be accentuated by those conditions. Conclusions Personality traits are prospectively associated with perceptions of the workplace. Workplace conditions are also associated with trait development. PMID:23336723

Nuclear Structure in 78Ge

NASA Astrophysics Data System (ADS)

Forney, Anne M.; Walters, W. B.; Sethi, J.; Chiara, C. J.; Harker, J.; Janssens, R. V. F.; Zhu, S.; Carpenter, M.; Alcorta, M.; Gürdal, G.; Hoffman, C. R.; Kay, B. P.; Kondev, F. G.; Lauristen, T.; Lister, C. J.; McCutchan, E. A.; Rogers, A. M.; Seweryniak, D.

2017-01-01

Owing to the importance of the structure of 76Ge in interpreting double β decay studies, the structures of adjacent nuclei have been of considerable interest. Recently reported features for the structures of 72,74,76Ge indicate both shape coexistence and triaxiality. New data for the excited states of 78Ge will be reported arising from Gammasphere studies of multinucleon transfer reactions between a 76Ge beam and thick heavy targets at the ATLAS facility at Argonne National Laboratory. The previously known yrast band is extended to higher spins, candidate levels for a triaxial sequence have been observed, and the associated staggering determined. The staggering in 78Ge found in this work is not in agreement with theoretical work. Candidates for negative-parity states and seniority-four states will be discussed. This material is based upon work supported by the U.S. DOE under DE-AC02-06CH11357 and DE-FG02-94ER40834. Resources of ANL's ATLAS setup, a DOE Office of Science user facility, were used.

A four-lens based plenoptic camera for depth measurements

NASA Astrophysics Data System (ADS)

Riou, Cécile; Deng, Zhiyuan; Colicchio, Bruno; Lauffenburger, Jean-Philippe; Kohler, Sophie; Haeberlé, Olivier; Cudel, Christophe

2015-04-01

In previous works, we have extended the principles of "variable homography", defined by Zhang and Greenspan, for measuring height of emergent fibers on glass and non-woven fabrics. This method has been defined for working with fabric samples progressing on a conveyor belt. Triggered acquisition of two successive images was needed to perform the 3D measurement. In this work, we have retained advantages of homography variable for measurements along Z axis, but we have reduced acquisitions number to a single one, by developing an acquisition device characterized by 4 lenses placed in front of a single image sensor. The idea is then to obtain four projected sub-images on a single CCD sensor. The device becomes a plenoptic or light field camera, capturing multiple views on the same image sensor. We have adapted the variable homography formulation for this device and we propose a new formulation to calculate a depth with plenoptic cameras. With these results, we have transformed our plenoptic camera in a depth camera and first results given are very promising.

USP7/HAUSP: A SUMO deubiquitinase at the heart of DNA replication.

PubMed

Smits, Veronique A J; Freire, Raimundo

2016-09-01

DNA replication is both highly conserved and controlled. Problematic DNA replication can lead to genomic instability and therefore carcinogenesis. Numerous mechanisms work together to achieve this tight control and increasing evidence suggests that post-translational modifications (phosphorylation, ubiquitination, SUMOylation) of DNA replication proteins play a pivotal role in this process. Here we discuss such modifications in the light of a recent article that describes a novel role for the deubiquitinase (DUB) USP7/HAUSP in the control of DNA replication. USP7 achieves this function by an unusual and novel mechanism, namely deubiquitination of SUMOylated proteins at the replication fork, making USP7 also a SUMO DUB (SDUB). This work extends previous observations of increased levels of SUMO and low levels of ubiquitin at the on-going replication fork. Here, we discuss this novel study, its contribution to the DNA replication and genomic stability field and what questions arise from this work. © 2016 WILEY Periodicals, Inc.

Summer temperatures inferred from varved lacustrine sediment at Iceberg Lake in southcentral Alaska

NASA Astrophysics Data System (ADS)

Diedrich, K.; Loso, M. G.

2010-12-01

Iceberg Lake, a glacier-dammed lake in southcentral Alaska, has been previously shown to record over 1,500 years of continuous laminated lacustrine sediment deposition. Because previous work was based on examination of subaerial outcrops exposed by stream incision in the bed of the jökulhlaup-drained lake, the length of the record was limited by the extent of the outcrops. In August of 2010, we returned to core the remote lake; our goal was recovery of the complete sedimentary record in the lake, extending perhaps back to the onset of late Holocene glaciation—around 3-5 ka in this region. We used a Vibarcorer system to recover sediment cores from two locations, one near the site of previous work and another at the distal end of the lake. The longest cores recovered were 5.2 meters and 6.2 meters at the proximal and distal sites, respectively. Based on the average lamination thickness established previously at the proximal site (4.7 mm), these cores should each represent over 1000 years of sediment accumulation, and likely much longer at the distal site, where laminations are expected to be thinner. Having established previously that the lake’s laminations are annual varves and that they are positively correlated with summer (melt-season) temperatures, our analysis is focused on documenting a long time-series of annual sediment accumulation and summer-layer particle size. Both measurements will be used to interpret the history of summer temperatures. The cores may also provide sedimentary evidence of the timing of advances/retreats of nearby glaciers, including the Tana Glacier and Bagley Icefield, helping to clarify the poorly-constrained timing of neoglaciation in Southern Alaska. The paleoclimate record produced at Iceberg Lake will be included in the Arctic System Science 8ka project

Microstructure and properties of thermally sprayed Al-Sn-based alloys for plain bearing applications

NASA Astrophysics Data System (ADS)

Marrocco, T.; Driver, L. C.; Harris, S. J.; McCartney, D. G.

2006-12-01

Al-Sn plain bearings for automotive applications traditionally comprise a multilayer structure. Conventionally, bearing manufacturing involves casting the Al-Sn alloy and roll-bonding to a steel backing strip. Recently, high-velocity oxyfuel (HVOF) thermal spraying has been used as a novel alternative manufacturing route. The present project extends previous work on ternary Al-Sn-Cu alloys to quaternary systems, which contain specific additions for potentially enhanced properties. Two alloys were studied in detail, namely, Al-20wt.%Sn-1wt.%Cu-2wt.%Ni and Al-20wt.%Sn-1wt.%Cu-7wt.%Si. This article will describe the microstructural evolution of these alloys following HVOF spraying onto steel substrates and subsequent heat treatment. The microstructures of powders and coatings were investigated by scanning electron microscopy, and the phases were identified by x-ray diffraction. Coating microhardnesses were determined under both as-sprayed and heat-treated conditions, and by the differences related to the microstructures that developed. Finally, the wear behavior of the sprayed and heat-treated coatings in hot engine oil was measured using an industry standard test and was compared with that of previous work on a ternary alloy.

Internal wave energy flux from density perturbations in nonlinear stratifications

NASA Astrophysics Data System (ADS)

Lee, Frank M.; Allshouse, Michael R.; Swinney, Harry L.; Morrison, P. J.

2017-11-01

Tidal flow over the topography at the bottom of the ocean, whose density varies with depth, generates internal gravity waves that have a significant impact on the energy budget of the ocean. Thus, understanding the energy flux (J = p v) is important, but it is difficult to measure simultaneously the pressure and velocity perturbation fields, p and v . In a previous work, a Green's-function-based method was developed to calculate the instantaneous p, v , and thus J , given a density perturbation field for a constant buoyancy frequency N. Here we extend the previous analytic Green's function work to include nonuniform N profiles, namely the tanh-shaped and linear cases, because background density stratifications that occur in the ocean and some experiments are nonlinear. In addition, we present a finite-difference method for the general case where N has an arbitrary profile. Each method is validated against numerical simulations. The methods we present can be applied to measured density perturbation data by using our MATLAB graphical user interface EnergyFlux. PJM was supported by the U.S. Department of Energy Contract DE-FG05-80ET-53088. HLS and MRA were supported by ONR Grant No. N000141110701.

Multiobjective Resource-Constrained Project Scheduling with a Time-Varying Number of Tasks

PubMed Central

Abello, Manuel Blanco

2014-01-01

In resource-constrained project scheduling (RCPS) problems, ongoing tasks are restricted to utilizing a fixed number of resources. This paper investigates a dynamic version of the RCPS problem where the number of tasks varies in time. Our previous work investigated a technique called mapping of task IDs for centroid-based approach with random immigrants (McBAR) that was used to solve the dynamic problem. However, the solution-searching ability of McBAR was investigated over only a few instances of the dynamic problem. As a consequence, only a small number of characteristics of McBAR, under the dynamics of the RCPS problem, were found. Further, only a few techniques were compared to McBAR with respect to its solution-searching ability for solving the dynamic problem. In this paper, (a) the significance of the subalgorithms of McBAR is investigated by comparing McBAR to several other techniques; and (b) the scope of investigation in the previous work is extended. In particular, McBAR is compared to a technique called, Estimation Distribution Algorithm (EDA). As with McBAR, EDA is applied to solve the dynamic problem, an application that is unique in the literature. PMID:24883398

UEDGE Simulations for Power and Particle Flow Analysis of FRC Rocket

NASA Astrophysics Data System (ADS)

Zheng, Fred; Evans, Eugene S.; McGreivy, Nick; Kaptanoglu, Alan; Izacard, Olivier; Cohen, Samuel A.

2017-10-01

The field-reversed configuration (FRC) is under consideration for use in a direct fusion drive (DFD) rocket propulsion system for future space missions. To achieve a rocket configuration, the FRC is embedded within an asymmetric magnetic mirror, in which one end is closed and contains a gas box, and the other end is open and incorporates a magnetic nozzle. Neutral deuterium is injected into the gas box, and flows through the scrape-off layer (SOL) around the core plasma and out the magnetic nozzle, both cooling the core and serving as propellant. Previous studies have examined a range of operating conditions for the SOL of a DFD using UEDGE, a 2D fluid code; discrepancies on the order of 5% were found during the analysis of overall power balance. This work extends the analysis of the previously-studied SOL geometry by updating boundary conditions and conducting a detailed study of power and particle flows within the simulation with the goals of modeling electrical power generation instead of thrust and achieving higher specific impulse. This work was supported, in part, by DOE Contract Number DE-AC02-09CH11466 and Princeton Environmental Institute.

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

Nersisyan, Henrik; Cid, Adrian Fernandez; Amendola, Luca, E-mail: h.nersisyan@thphys.uni-heidelberg.de, E-mail: fernandez@thphys.uni-heidelberg.de, E-mail: l.amendola@thphys.uni-heidelberg.de

In this work, we extend previous analyses of the structure formation in the f (□{sup −1} R ) model of nonlocal gravity proposed by Deser and Woodard (DW), which reproduces the background expansion of ΛCDM with no need of a cosmological constant nor of any dimensional constant beside Newton's one. A previous analysis based on redshift-space distortions (RSD) data concluded that the model was ruled out. In this work we revisit the issue and find that, when recast in a localized model, the DW model is not ruled out and actually gives a better fit to RSD data than ΛCDM.more » In fact, the DW model presents a suppressed growth of matter perturbations with respect to ΛCDM and a slightly lower value of σ{sub 8}, as favored by observations. We also produce analytical approximations of the two modified gravity functions, i.e. the anisotropic stress η and the relative change of Newton's constant Y , and of f σ{sub 8}( z ) as a function of redshift. Finally, we also show how much the fit depends on initial conditions when these are generalized with respect to a standard matter-dominated era.« less

Hyper-Fractal Analysis: A visual tool for estimating the fractal dimension of 4D objects

NASA Astrophysics Data System (ADS)

Grossu, I. V.; Grossu, I.; Felea, D.; Besliu, C.; Jipa, Al.; Esanu, T.; Bordeianu, C. C.; Stan, E.

2013-04-01

This work presents a new version of a Visual Basic 6.0 application for estimating the fractal dimension of images and 3D objects (Grossu et al. (2010) [1]). The program was extended for working with four-dimensional objects stored in comma separated values files. This might be of interest in biomedicine, for analyzing the evolution in time of three-dimensional images. New version program summaryProgram title: Hyper-Fractal Analysis (Fractal Analysis v03) Catalogue identifier: AEEG_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEG_v3_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 745761 No. of bytes in distributed program, including test data, etc.: 12544491 Distribution format: tar.gz Programming language: MS Visual Basic 6.0 Computer: PC Operating system: MS Windows 98 or later RAM: 100M Classification: 14 Catalogue identifier of previous version: AEEG_v2_0 Journal reference of previous version: Comput. Phys. Comm. 181 (2010) 831-832 Does the new version supersede the previous version? Yes Nature of problem: Estimating the fractal dimension of 4D images. Solution method: Optimized implementation of the 4D box-counting algorithm. Reasons for new version: Inspired by existing applications of 3D fractals in biomedicine [3], we extended the optimized version of the box-counting algorithm [1, 2] to the four-dimensional case. This might be of interest in analyzing the evolution in time of 3D images. The box-counting algorithm was extended in order to support 4D objects, stored in comma separated values files. A new form was added for generating 2D, 3D, and 4D test data. The application was tested on 4D objects with known dimension, e.g. the Sierpinski hypertetrahedron gasket, Df=ln(5)/ln(2) (Fig. 1). The algorithm could be extended, with minimum effort, to higher number of dimensions. Easy integration with other applications by using the very simple comma separated values file format for storing multi-dimensional images. Implementation of χ2 test as a criterion for deciding whether an object is fractal or not. User friendly graphical interface. Hyper-Fractal Analysis-Test on the Sierpinski hypertetrahedron 4D gasket (Df=ln(5)/ln(2)≅2.32). Running time: In a first approximation, the algorithm is linear [2]. References: [1] V. Grossu, D. Felea, C. Besliu, Al. Jipa, C.C. Bordeianu, E. Stan, T. Esanu, Computer Physics Communications, 181 (2010) 831-832. [2] I.V. Grossu, C. Besliu, M.V. Rusu, Al. Jipa, C. C. Bordeianu, D. Felea, Computer Physics Communications, 180 (2009) 1999-2001. [3] J. Ruiz de Miras, J. Navas, P. Villoslada, F.J. Esteban, Computer Methods and Programs in Biomedicine, 104 Issue 3 (2011) 452-460.

SU-E-J-167: Improvement of Time-Ordered Four Dimensional Cone-Beam CT; Image Mosaicing with Real and Virtual Projections

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

Nakano, M; Kida, S; Masutani, Y

2014-06-01

Purpose: In the previous study, we developed time-ordered fourdimensional (4D) cone-beam CT (CBCT) technique to visualize nonperiodic organ motion, such as peristaltic motion of gastrointestinal organs and adjacent area, using half-scan reconstruction method. One important obstacle was that truncation of projection was caused by asymmetric location of flat-panel detector (FPD) in order to cover whole abdomen or pelvis in one rotation. In this study, we propose image mosaicing to extend projection data to make possible to reconstruct full field-of-view (FOV) image using half-scan reconstruction. Methods: The projections of prostate cancer patients were acquired using the X-ray Volume Imaging system (XVI,more » version 4.5) on Synergy linear accelerator system (Elekta, UK). The XVI system has three options of FOV, S, M and L, and M FOV was chosen for pelvic CBCT acquisition, with a FPD panel 11.5 cm offset. The method to produce extended projections consists of three main steps: First, normal three-dimensional (3D) reconstruction which contains whole pelvis was implemented using real projections. Second, virtual projections were produced by reprojection process of the reconstructed 3D image. Third, real and virtual projections in each angle were combined into one extended mosaic projection. Then, 4D CBCT images were reconstructed using our inhouse reconstruction software based on Feldkamp, Davis and Kress algorithm. The angular range of each reconstruction phase in the 4D reconstruction was 180 degrees, and the range moved as time progressed. Results: Projection data were successfully extended without discontinuous boundary between real and virtual projections. Using mosaic projections, 4D CBCT image sets were reconstructed without artifacts caused by the truncation, and thus, whole pelvis was clearly visible. Conclusion: The present method provides extended projections which contain whole pelvis. The presented reconstruction method also enables time-ordered 4D CBCT reconstruction of organs with non-periodic motion with full FOV without projection-truncation artifacts. This work was partly supported by the JSPS Core-to-Core Program(No. 23003). This work was partly supported by JSPS KAKENHI 24234567.« less

Extending Working Life: Which Competencies are Crucial in Near-Retirement Age?

PubMed

Wiktorowicz, Justyna

2018-01-01

Nowadays, one of the most important economic and social phenomena is population ageing. Due to the low activity rate of older people, one of the most important challenges is to take various actions involving active ageing, which is supposed to extending working life, and along with it-improve the competencies of older people. The aim of this paper is to evaluate the relevance of different competencies for extending working life, with limiting the analysis for Poland. The paper also assesses the competencies of mature Polish people (aged 50+, but still in working age). In the statistical analysis, I used logistic regression, as well as descriptive statistics and appropriate statistical tests. The results show that among the actions aimed at extending working life, the most important are those related to lifelong learning, targeted at improving the competencies of the older generation. The competencies (both soft and hard) of people aged 50+ are more important than their formal education.

Effects of extended work shifts and shift work on patient safety, productivity, and employee health.

PubMed

Keller, Simone M

2009-12-01

It is estimated 1.3 million health care errors occur each year and of those errors 48,000 to 98,000 result in the deaths of patients (Barger et al., 2006). Errors occur for a variety of reasons, including the effects of extended work hours and shift work. The need for around-the-clock staff coverage has resulted in creative ways to maintain quality patient care, keep health care errors or adverse events to a minimum, and still meet the needs of the organization. One way organizations have attempted to alleviate staff shortages is to create extended work shifts. Instead of the standard 8-hour shift, workers are now working 10, 12, 16, or more hours to provide continuous patient care. Although literature does support these staffing patterns, it cannot be denied that shifts beyond the traditional 8 hours increase staff fatigue, health care errors, and adverse events and outcomes and decrease alertness and productivity. This article includes a review of current literature on shift work, the definition of shift work, error rates and adverse outcomes related to shift work, health effects on shift workers, shift work effects on older workers, recommended optimal shift length, positive and negative effects of shift work on the shift worker, hazards associated with driving after extended shifts, and implications for occupational health nurses. Copyright 2009, SLACK Incorporated.

A Linearized Model for Flicker and Contrast Thresholds at Various Retinal Illuminances

NASA Technical Reports Server (NTRS)

Ahumada, Albert; Watson, Andrew

2015-01-01

We previously proposed a flicker visibility metric for bright displays, based on psychophysical data collected at a high mean luminance. Here we extend the metric to other mean luminances. This extension relies on a linear relation between log sensitivity and critical fusion frequency, and a linear relation between critical fusion frequency and log retina lilluminance. Consistent with our previous metric, the extended flicker visibility metric is measured in just-noticeable differences (JNDs).

Real-time measurement of size-resolved elemental composition ratio for flame synthesized composite nanoparticle aggregates using a tandem SMPS-ICP-OES

PubMed Central

Reed, Nathan; Fang, Jiaxi; Chavalmane, Sanmathi; Biswas, Pratim

2017-01-01

Composite nanoparticles find application in catalysis, drug delivery, and energy storage and require increasingly fine control of their physical properties and composition. While composite nanoparticles have been widely synthesized and characterized, little work has systematically correlated the initial concentration of precursors and the final composition of flame synthesized composite nanoparticles. This relationship is explored in a diffusion flame aerosol reactor by coupling a scanning mobility particle sizer (SMPS) with an inductively coupled plasma optical emission spectrometer (ICP-OES). A framework for studying the relationship between the initial precursor concentrations of different elements and the final nanoparticle composition is explored. The size-resolved elemental composition was measured by directly injecting size-selected fractions of aggregated magnetite and silicon dioxide composite nanoparticles into the ICP-OES plasma. This work showed a correlation between precursor molar ratio and the measured elemental ratio in the mobility size range of 50 to 140 nm. Building on previous work studying size resolved elemental composition of engineered nanoparticles, the analysis is extended to flame synthesized composite nanoparticle aggregates in this work. PMID:28435179

Real-time measurement of size-resolved elemental composition ratio for flame synthesized composite nanoparticle aggregates using a tandem SMPS-ICP-OES.

PubMed

Reed, Nathan; Fang, Jiaxi; Chavalmane, Sanmathi; Biswas, Pratim

2017-01-01

Composite nanoparticles find application in catalysis, drug delivery, and energy storage and require increasingly fine control of their physical properties and composition. While composite nanoparticles have been widely synthesized and characterized, little work has systematically correlated the initial concentration of precursors and the final composition of flame synthesized composite nanoparticles. This relationship is explored in a diffusion flame aerosol reactor by coupling a scanning mobility particle sizer (SMPS) with an inductively coupled plasma optical emission spectrometer (ICP-OES). A framework for studying the relationship between the initial precursor concentrations of different elements and the final nanoparticle composition is explored. The size-resolved elemental composition was measured by directly injecting size-selected fractions of aggregated magnetite and silicon dioxide composite nanoparticles into the ICP-OES plasma. This work showed a correlation between precursor molar ratio and the measured elemental ratio in the mobility size range of 50 to 140 nm. Building on previous work studying size resolved elemental composition of engineered nanoparticles, the analysis is extended to flame synthesized composite nanoparticle aggregates in this work.

MMA-EoS: A Computational Framework for Mineralogical Thermodynamics

NASA Astrophysics Data System (ADS)

Chust, T. C.; Steinle-Neumann, G.; Dolejš, D.; Schuberth, B. S. A.; Bunge, H.-P.

2017-12-01

We present a newly developed software framework, MMA-EoS, that evaluates phase equilibria and thermodynamic properties of multicomponent systems by Gibbs energy minimization, with application to mantle petrology. The code is versatile in terms of the equation-of-state and mixing properties and allows for the computation of properties of single phases, solution phases, and multiphase aggregates. Currently, the open program distribution contains equation-of-state formulations widely used, that is, Caloric-Murnaghan, Caloric-Modified-Tait, and Birch-Murnaghan-Mie-Grüneisen-Debye models, with published databases included. Through its modular design and easily scripted database, MMA-EoS can readily be extended with new formulations of equations-of-state and changes or extensions to thermodynamic data sets. We demonstrate the application of the program by reproducing and comparing physical properties of mantle phases and assemblages with previously published work and experimental data, successively increasing complexity, up to computing phase equilibria of six-component compositions. Chemically complex systems allow us to trace the budget of minor chemical components in order to explore whether they lead to the formation of new phases or extend stability fields of existing ones. Self-consistently computed thermophysical properties for a homogeneous mantle and a mechanical mixture of slab lithologies show no discernible differences that require a heterogeneous mantle structure as has been suggested previously. Such examples illustrate how thermodynamics of mantle mineralogy can advance the study of Earth's interior.

The disruptive effects of methamphetamine on delayed-matching-to-sample performance reflect proactive interference and are reduced by SCH23390.

PubMed

Macaskill, Anne C; Harrow, Catherine C; Harper, David N

2015-01-01

Different drugs produce different patterns of impairment on delayed matching-to-sample tasks. For example, (+/-)3,4-methylenedioxymethamphetamine (MDMA) produces an increase in proactive interference. That is, subjects are less accurate when they are required to make a response different to the one they made on the immediately previous trial. The current study assessed whether methamphetamine also produces this particular pattern of disruption in delayed matching-to-sample performance in rats. Methamphetamine primarily reduced accuracy on trials where the correct response differed from the one made on the previous trial. Thus methamphetamine, like MDMA and other stimulant-based drugs of abuse, increased proactive interference. This impairment was reduced by prior administration of the dopamine D1 antagonist SCH23390. These results further extend a general conclusion that a range of stimulant-based drugs may disrupt working memory function indirectly via a tendency to repeat previously made responses and that this disruption is related to D1 receptor activity. Copyright © 2014 Elsevier Inc. All rights reserved.

Integration of Pragmatic and Phonetic Cues in Spoken Word Recognition

PubMed Central

Rohde, Hannah; Ettlinger, Marc

2015-01-01

Although previous research has established that multiple top-down factors guide the identification of words during speech processing, the ultimate range of information sources that listeners integrate from different levels of linguistic structure is still unknown. In a set of experiments, we investigate whether comprehenders can integrate information from the two most disparate domains: pragmatic inference and phonetic perception. Using contexts that trigger pragmatic expectations regarding upcoming coreference (expectations for either he or she), we test listeners' identification of phonetic category boundaries (using acoustically ambiguous words on the/hi/∼/∫i/continuum). The results indicate that, in addition to phonetic cues, word recognition also reflects pragmatic inference. These findings are consistent with evidence for top-down contextual effects from lexical, syntactic, and semantic cues, but they extend this previous work by testing cues at the pragmatic level and by eliminating a statistical-frequency confound that might otherwise explain the previously reported results. We conclude by exploring the time-course of this interaction and discussing how different models of cue integration could be adapted to account for our results. PMID:22250908

Reflection does not undermine self-interested prosociality

PubMed Central

Rand, David G.; Kraft-Todd, Gordon T.

2014-01-01

The cognitive basis of prosocial behavior has received considerable recent attention. Previous work using economic games has found that in social dilemmas, intuitive decisions are more prosocial on average. The Social Heuristics Hypothesis (SHH) explains this result by contending that strategies which are successful in daily life become automatized as intuitions. Deliberation then causes participants to adjust to the self-interested strategy in the specific setting at hand. Here we provide further evidence for the SHH by confirming several predictions regarding when and for whom time pressure/delay will and will not alter contributions in a Public Goods Game (PGG). First, we replicate and extend previous results showing that (as predicted by the SHH) trust of daily-life interaction partners and previous experience with economic games moderate the effect of time pressure/delay in social dilemmas. We then confirm a novel prediction of the SHH: that deliberation should not undermine the decision to benefit others when doing so is also individually payoff-maximizing. Our results lend further support to the SHH, and shed light on the role that deliberation plays in social dilemmas. PMID:25232309

Reflection does not undermine self-interested prosociality.

PubMed

Rand, David G; Kraft-Todd, Gordon T

2014-01-01

The cognitive basis of prosocial behavior has received considerable recent attention. Previous work using economic games has found that in social dilemmas, intuitive decisions are more prosocial on average. The Social Heuristics Hypothesis (SHH) explains this result by contending that strategies which are successful in daily life become automatized as intuitions. Deliberation then causes participants to adjust to the self-interested strategy in the specific setting at hand. Here we provide further evidence for the SHH by confirming several predictions regarding when and for whom time pressure/delay will and will not alter contributions in a Public Goods Game (PGG). First, we replicate and extend previous results showing that (as predicted by the SHH) trust of daily-life interaction partners and previous experience with economic games moderate the effect of time pressure/delay in social dilemmas. We then confirm a novel prediction of the SHH: that deliberation should not undermine the decision to benefit others when doing so is also individually payoff-maximizing. Our results lend further support to the SHH, and shed light on the role that deliberation plays in social dilemmas.

Improving cerebellar segmentation with statistical fusion

NASA Astrophysics Data System (ADS)

Plassard, Andrew J.; Yang, Zhen; Prince, Jerry L.; Claassen, Daniel O.; Landman, Bennett A.

2016-03-01

The cerebellum is a somatotopically organized central component of the central nervous system well known to be involved with motor coordination and increasingly recognized roles in cognition and planning. Recent work in multiatlas labeling has created methods that offer the potential for fully automated 3-D parcellation of the cerebellar lobules and vermis (which are organizationally equivalent to cortical gray matter areas). This work explores the trade offs of using different statistical fusion techniques and post hoc optimizations in two datasets with distinct imaging protocols. We offer a novel fusion technique by extending the ideas of the Selective and Iterative Method for Performance Level Estimation (SIMPLE) to a patch-based performance model. We demonstrate the effectiveness of our algorithm, Non- Local SIMPLE, for segmentation of a mixed population of healthy subjects and patients with severe cerebellar anatomy. Under the first imaging protocol, we show that Non-Local SIMPLE outperforms previous gold-standard segmentation techniques. In the second imaging protocol, we show that Non-Local SIMPLE outperforms previous gold standard techniques but is outperformed by a non-locally weighted vote with the deeper population of atlases available. This work advances the state of the art in open source cerebellar segmentation algorithms and offers the opportunity for routinely including cerebellar segmentation in magnetic resonance imaging studies that acquire whole brain T1-weighted volumes with approximately 1 mm isotropic resolution.

Maintenance effects of working memory intervention (Cogmed) in children with symptomatic epilepsy.

PubMed

Fuentes, Amanda; Kerr, Elizabeth N

2017-02-01

To extend previous research documenting the benefits of working memory (WM) intervention (Cogmed) immediately post-intervention in children with epilepsy by assessing the 3-month maintenance effects. Participants involved in a previous randomized clinical trial (RCT) were invited to participate if they completed Cogmed within the last 3months (n=15) and additional participants (n=13) were prospectively recruited. Standardized assessments of near-transfer effects (i.e., visual and auditory attention and WM) were completed prior to and immediately after intervention and at 3-month follow-up. An additional measure assessing the far-transfer effect of fluid reasoning was administered prior to intervention and at 3-month follow-up. Participants exhibited gains in auditory and visual attention and WM immediately following intervention and gains were generally sustained at 3-month follow-up. Intervention did not improve visual-verbal WM or fluid reasoning. The clinical variables studied (i.e., age of seizure onset, seizure frequency, epilepsy duration, and overall intellectual functioning) did not elucidate reliable relationships with intervention. Working memory training is possibly efficacious in improving related skills which are maintained for 3months in children with active epilepsy. No transfer to fluid reasoning was documented. Further investigation by means of a large-scale RCT which includes a placebo and both objective and subjective measures of the impact of training on daily functioning is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

New contributions to granite characterization by ultrasonic testing.

PubMed

Cerrillo, C; Jiménez, A; Rufo, M; Paniagua, J; Pachón, F T

2014-01-01

Ultrasound evaluation permits the state of rocks to be determined quickly and cheaply, satisfying the demands faced by today's producers of ornamental stone, such as environmental sustainability, durability and safety of use. The basic objective of the present work is to analyse and develop the usefulness of ultrasound testing in estimating the physico-mechanical properties of granite. Various parameters related to Fast Fourier Transform (FFTs) and attenuation have been extracted from some of the studies conducted (parameters which have not previously been considered in work on this topic, unlike the ultrasonic pulse velocity). The experimental study was carried out on cubic specimens of 30 cm edges using longitudinal and shear wave transducers and equipment which extended the normally used natural resonance frequency range up to 500 kHz. Additionally, a validation study of the laboratory data has been conducted and some methodological improvements have been implemented. The main contribution of the work is the analysis of linear statistical correlations between the aforementioned new ultrasound parameters and physico-mechanical properties of the granites that had not previously been studied, i.e., resistance to salt crystallization and breaking load for anchors. Being properties that directly affect the durability and safety of use of granites, these correlations consolidate ultrasonics as a nondestructive method well suited to this type of material. Copyright © 2013 Elsevier B.V. All rights reserved.

Route Optimization for Offloading Congested Meter Fixes

NASA Technical Reports Server (NTRS)

Xue, Min; Zelinski, Shannon

2016-01-01

The Optimized Route Capability (ORC) concept proposed by the FAA facilitates traffic managers to identify and resolve arrival flight delays caused by bottlenecks formed at arrival meter fixes when there exists imbalance between arrival fixes and runways. ORC makes use of the prediction capability of existing automation tools, monitors the traffic delays based on these predictions, and searches the best reroutes upstream of the meter fixes based on the predictions and estimated arrival schedules when delays are over a predefined threshold. Initial implementation and evaluation of the ORC concept considered only reroutes available at the time arrival congestion was first predicted. This work extends previous work by introducing an additional dimension in reroute options such that ORC can find the best time to reroute and overcome the 'firstcome- first-reroute' phenomenon. To deal with the enlarged reroute solution space, a genetic algorithm was developed to solve this problem. Experiments were conducted using the same traffic scenario used in previous work, when an arrival rush was created for one of the four arrival meter fixes at George Bush Intercontinental Houston Airport. Results showed the new approach further improved delay savings. The suggested route changes from the new approach were on average 30 minutes later than those using other approaches, and fewer numbers of reroutes were required. Fewer numbers of reroutes reduce operational complexity and later reroutes help decision makers deal with uncertain situations.

Barriers to Later Retirement for Men: Physical Challenges of Work and Increases in the Full Retirement Age.

PubMed

McLaughlin, Joanne Song; Neumark, David

2018-03-01

Policy changes intended to delay retirements of older workers and extend their work lives may run up against barriers owing to rising physical challenges of work as people age. We examine whether physical challenges at work influence employment transitions of older male workers in the age range for which public policy is trying to extend work lives and whether older male workers are able to mitigate these challenges while still remaining employed. The evidence indicates that physical challenges pose a barrier to extending work lives, although some older male workers with physically demanding jobs are able to mitigate these demands-either at new jobs or with the same employer. Our findings suggest that greater accommodation of physical challenges faced by older workers would likely increase the success of policies intended to induce later retirement.

The resonator handbook

NASA Technical Reports Server (NTRS)

Cook, Jerry D.; Zhou, Shiliang

1993-01-01

The purpose of this work is to extend resonator theory into the region in which the planar mirror is quite small. Results of the theoretical description are then extended to resonator design and experimental arrangements as discussed in further sections of this work. Finally, a discussion of dielectric measurements for small samples is included as a specific application of this work.

Extended working hours: Impacts on workers

Treesearch

D. Mitchell; T. Gallagher

2010-01-01

Some logging business owners are trying to manage their equipment assets by increasing the scheduled machine hours. The intent is to maximize the total tons produced by a set of equipment. This practice is referred to as multi-shifting, double-shifting, or extended working hours. One area often overlooked is the impact that working non-traditional hours can have on...

Solar System constraints on renormalization group extended general relativity: The PPN and Laplace-Runge-Lenz analyses with the external potential effect

NASA Astrophysics Data System (ADS)

Rodrigues, Davi C.; Mauro, Sebastião; de Almeida, Álefe O. F.

2016-10-01

General relativity extensions based on renormalization group effects are motivated by a known physical principle and constitute a class of extended gravity theories that have some unexplored unique aspects. In this work we develop in detail the Newtonian and post-Newtonian limits of a realization called renormalization group extended general relativity (RGGR). Special attention is given to the external potential effect, which constitutes a type of screening mechanism typical of RGGR. In the Solar System, RGGR depends on a single dimensionless parameter ν¯⊙, and this parameter is such that for ν¯⊙=0 one fully recovers GR in the Solar System. Previously this parameter was constrained to be |ν¯ ⊙|≲10-21 , without considering the external potential effect. Here we show that under a certain approximation RGGR can be cast in a form compatible with the parametrized post-Newtonian (PPN) formalism, and we use both the PPN formalism and the Laplace-Runge-Lenz technique to put new bounds on ν¯⊙, either considering or not the external potential effect. With the external potential effect the new bound reads |ν¯ ⊙|≲10-16 . We discuss the possible consequences of this bound on the dark matter abundance in galaxies.

Secreted Amyloid β-Proteins in a Cell Culture Model Include N-Terminally Extended Peptides That Impair Synaptic Plasticity

PubMed Central

2014-01-01

Evidence for a central role of amyloid β-protein (Aβ) in the genesis of Alzheimer’s disease (AD) has led to advanced human trials of Aβ-lowering agents. The “amyloid hypothesis” of AD postulates deleterious effects of small, soluble forms of Aβ on synaptic form and function. Because selectively targeting synaptotoxic forms of soluble Aβ could be therapeutically advantageous, it is important to understand the full range of soluble Aβ derivatives. We previously described a Chinese hamster ovary (CHO) cell line (7PA2 cells) that stably expresses mutant human amyloid precursor protein (APP). Here, we extend this work by purifying an sodium dodecyl sulfate (SDS)-stable, ∼8 kDa Aβ species from the 7PA2 medium. Mass spectrometry confirmed its identity as a noncovalently bonded Aβ40 homodimer that impaired hippocampal long-term potentiation (LTP) in vivo. We further report the detection of Aβ-containing fragments of APP in the 7PA2 medium that extend N-terminal from Asp1 of Aβ. These N-terminally extended Aβ-containing monomeric fragments are distinct from soluble Aβ oligomers formed from Aβ1-40/42 monomers and are bioactive synaptotoxins secreted by 7PA2 cells. Importantly, decreasing β-secretase processing of APP elevated these alternative synaptotoxic APP fragments. We conclude that certain synaptotoxic Aβ-containing species can arise from APP processing events N-terminal to the classical β-secretase cleavage site. PMID:24840308

Another Simple yet Effective Best Practice for Increasing Enrollments at an Extended Campus

ERIC Educational Resources Information Center

Christensen, Steven S.; Howell, Scott L.; Hall, C. Giles

2016-01-01

This article is a follow-up to a previous article, "Six Ways to Increase Enrollments at an Extended Campus," published in this journal (vol. 17, no. 4, winter 2015), wherein a seventh best practice to increase course offerings and increase enrollments at an extended campus is presented. This best practice seeks to identify those areas of…

A retrospective cohort study of shift work and risk of cancer-specific mortality in German male chemical workers.

PubMed

Yong, Mei; Nasterlack, Michael; Messerer, Peter; Oberlinner, Christoph; Lang, Stefan

2014-02-01

Human evidence of carcinogenicity concerning shift work is inconsistent. In a previous study, we observed no elevated risk of total mortality in shift workers followed up until the end of 2006. The present study aimed to investigate cancer-specific mortality, relative to shift work. The cohort consisted of male production workers (14,038 shift work and 17,105 day work), employed at BASF Ludwigshafen for at least 1 year between 1995 and 2005. Vital status was followed from 2000 to 2009. Cause-specific mortality was obtained from death certificates. Exposure to shift work was measured both as a dichotomous and continuous variable. While lifetime job history was not available, job duration in the company was derived from personal data, which was then categorized at the quartiles. Cox proportional hazard model was used to adjust for potential confounders, in which job duration was treated as a time-dependent covariate. Between 2000 and 2009, there were 513 and 549 deaths among rotating shift and day work employees, respectively. Risks of total and cancer-specific mortalities were marginally lower among shift workers when taking age at entry and job level into consideration and were statistically significantly lower when cigarette smoking, alcohol intake, job duration, and chronic disease prevalence at entry to follow-up were included as explanatory factors. With respect to mortality risks in relation to exposure duration, no increased risks were found in any of the exposure groups after full adjustment and there was no apparent trend suggesting an exposure-response relation with duration of shift work. The present analysis extends and confirms our previous finding of no excess risk of mortality associated with work in the shift system employed at BASF Ludwigshafen. More specifically, there is also no indication of an increased risk of mortality due to cancer.

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

Cabello, Adan

We introduce an extended version of a previous all-versus-nothing proof of impossibility of Einstein-Podolsky-Rosen's local elements of reality for two photons entangled both in polarization and path degrees of freedom (A. Cabello, quant-ph/0507259), which leads to a Bell's inequality where the classical bound is 8 and the quantum prediction is 16. A simple estimation of the detection efficiency required to close the detection loophole using this extended version gives {eta}>0.69. This efficiency is lower than that required for previous proposals.

Watermarking scheme for authentication of compressed image

NASA Astrophysics Data System (ADS)

Hsieh, Tsung-Han; Li, Chang-Tsun; Wang, Shuo

2003-11-01

As images are commonly transmitted or stored in compressed form such as JPEG, to extend the applicability of our previous work, a new scheme for embedding watermark in compressed domain without resorting to cryptography is proposed. In this work, a target image is first DCT transformed and quantised. Then, all the coefficients are implicitly watermarked in order to minimize the risk of being attacked on the unwatermarked coefficients. The watermarking is done through registering/blending the zero-valued coefficients with a binary sequence to create the watermark and involving the unembedded coefficients during the process of embedding the selected coefficients. The second-order neighbors and the block itself are considered in the process of the watermark embedding in order to thwart different attacks such as cover-up, vector quantisation, and transplantation. The experiments demonstrate the capability of the proposed scheme in thwarting local tampering, geometric transformation such as cropping, and common signal operations such as lowpass filtering.

Climate Change Impacts on Agriculture and Food Security in 2050 under a Range of Plausible Socioeconomic and Emissions Scenarios

NASA Astrophysics Data System (ADS)

Wiebe, K.; Lotze-Campen, H.; Bodirsky, B.; Kavallari, A.; Mason-d'Croz, D.; van der Mensbrugghe, D.; Robinson, S.; Sands, R.; Tabeau, A.; Willenbockel, D.; Islam, S.; van Meijl, H.; Mueller, C.; Robertson, R.

2014-12-01

Previous studies have combined climate, crop and economic models to examine the impact of climate change on agricultural production and food security, but results have varied widely due to differences in models, scenarios and data. Recent work has examined (and narrowed) these differences through systematic model intercomparison using a high-emissions pathway to highlight the differences. New work extends that analysis to cover a range of plausible socioeconomic scenarios and emission pathways. Results from three general circulation models are combined with one crop model and five global economic models to examine the global and regional impacts of climate change on yields, area, production, prices and trade for coarse grains, rice, wheat, oilseeds and sugar to 2050. Results show that yield impacts vary with changes in population, income and technology as well as emissions, but are reduced in all cases by endogenous changes in prices and other variables.

Code subspaces for LLM geometries

NASA Astrophysics Data System (ADS)

Berenstein, David; Miller, Alexandra

2018-03-01

We consider effective field theory around classical background geometries with a gauge theory dual, specifically those in the class of LLM geometries. These are dual to half-BPS states of N= 4 SYM. We find that the language of code subspaces is natural for discussing the set of nearby states, which are built by acting with effective fields on these backgrounds. This work extends our previous work by going beyond the strict infinite N limit. We further discuss how one can extract the topology of the state beyond N→∞ and find that, as before, uncertainty and entanglement entropy calculations provide a useful tool to do so. Finally, we discuss obstructions to writing down a globally defined metric operator. We find that the answer depends on the choice of reference state that one starts with. Therefore, within this setup, there is ambiguity in trying to write an operator that describes the metric globally.

Taboo: Working memory and mental control in an interactive task

PubMed Central

Hansen, Whitney A.; Goldinger, Stephen D.

2014-01-01

Individual differences in working memory (WM) predict principled variation in tasks of reasoning, response time, memory, and other abilities. Theoretically, a central function of WM is keeping task-relevant information easily accessible while suppressing irrelevant information. The present experiment was a novel study of mental control, using performance in the game Taboo as a measure. We tested effects of WM capacity on several indices, including perseveration errors (repeating previous guesses or clues) and taboo errors (saying at least part of a taboo or target word). By most measures, high-span participants were superior to low-span participants: High-spans were better at guessing answers, better at encouraging correct guesses from teammates, and less likely to either repeat themselves or produce taboo clues. Differences in taboo errors occurred only in an easy control condition. The results suggest that WM capacity predicts behavior in tasks requiring mental control, extending this finding to an interactive group setting. PMID:19827699

The contribution of disengagement to temporal discriminability.

PubMed

Shipstead, Zach; Nespodzany, Ashley

2018-05-01

The present study examines the idea that time-based forgetting of outdated information can lead to better memory of currently relevant information. This was done using the visual arrays task, along with a between-subjects manipulation of both the retention interval (1 s vs. 4 s) and the time between two trials (1 s vs. 4 s). Consistent with prior work [Shipstead, Z., & Engle, R. W. (2013). Interference within the focus of attention: Working memory tasks reflect more than temporary maintenance. Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 277-289; Experiment 1], longer retention intervals did not lead to diminished memory of currently relevant information. However, we did find that longer periods of time between two trials improved memory for currently relevant information. This replicates findings that indicate proactive interference affects visual arrays performance and extends previous findings to show that reduction of proactive interference can occur in a time-dependent manner.

Breast cancer screening services: trade-offs in quality, capacity, outreach, and centralization.

PubMed

Güneş, Evrim D; Chick, Stephen E; Akşin, O Zeynep

2004-11-01

This work combines and extends previous work on breast cancer screening models by explicitly incorporating, for the first time, aspects of the dynamics of health care states, program outreach, and the screening volume-quality relationship in a service system model to examine the effect of public health policy and service capacity decisions on public health outcomes. We consider the impact of increasing standards for minimum reading volume to improve quality, expanding outreach with or without decentralization of service facilities, and the potential of queueing due to stochastic effects and limited capacity. The results indicate a strong relation between screening quality and the cost of screening and treatment, and emphasize the importance of accounting for service dynamics when assessing the performance of health care interventions. For breast cancer screening, increasing outreach without improving quality and maintaining capacity results in less benefit than predicted by standard models.

Review of subcooled flow boiling critical heat flux (CHF) and its application to fusion energy system components part II: microconvective, experimental and correlational aspects

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

Boyd, R.D.

This paper reviews the present understanding of critical heat flux (CHF) in subcooled flow boiling and outlines research directions which will permit the accommodation of higher heat fluxes. This survey, which covers the last 30 years, is concerned only with CHF in the subcooled flow boiling regime and unless otherwise noted, all references to CHF will be confined to that regime. This paper (Part II) summarizes microconvective, instability, experimental and correlational aspects of CHF. Section II covers microconvection and instabilities, section III covers representative experimental work, and section IV summarizes and compares selected CHF correlations. Section V documents previous flowmore » visualization work and section VI contains conclusions and recommendations concerning problem areas and suggested research directions essential to the HHFCDP, which involves extending steady state and transient CHF towards 30 kW/cm/sup 2/.« less

Control theory based airfoil design using the Euler equations

NASA Technical Reports Server (NTRS)

Jameson, Antony; Reuther, James

1994-01-01

This paper describes the implementation of optimization techniques based on control theory for airfoil design. In our previous work it was shown that control theory could be employed to devise effective optimization procedures for two-dimensional profiles by using the potential flow equation with either a conformal mapping or a general coordinate system. The goal of our present work is to extend the development to treat the Euler equations in two-dimensions by procedures that can readily be generalized to treat complex shapes in three-dimensions. Therefore, we have developed methods which can address airfoil design through either an analytic mapping or an arbitrary grid perturbation method applied to a finite volume discretization of the Euler equations. Here the control law serves to provide computationally inexpensive gradient information to a standard numerical optimization method. Results are presented for both the inverse problem and drag minimization problem.

An Investigation of the Relationship Between the Alliance Negotiation Scale and Psychotherapy Process and Outcome.

PubMed

Doran, Jennifer M; Safran, Jeremy D; Muran, J Christopher

2017-04-01

This study examines the validity of the Alliance Negotiation Scale (ANS) in a psychotherapy research program. Analyses were designed to evaluate the relationship between the ANS and psychotherapy process and outcome variables. Data were collected in a metropolitan psychotherapy research program. Participants completed 30 sessions of therapy, postsession assessments, and a battery of measures at intake and termination. Relationships were found between the ANS and session outcome, working alliance, and the presence of ruptures and their resolution. Relationships emerged between the ANS and treatment outcome on measures of psychiatric distress and interpersonal problems. The ANS demonstrated relationships with several psychotherapy process and outcome variables. The ANS was the most differentiated from the working alliance on measures of interpersonal functioning and in discriminating personality disorder pathology. These results extend previous findings on the ANS' psychometric integrity, and offer new data on the relationship between negotiation and treatment outcome. © 2016 Wiley Periodicals, Inc.

Multiclass feature selection for improved pediatric brain tumor segmentation

NASA Astrophysics Data System (ADS)

Ahmed, Shaheen; Iftekharuddin, Khan M.

2012-03-01

In our previous work, we showed that fractal-based texture features are effective in detection, segmentation and classification of posterior-fossa (PF) pediatric brain tumor in multimodality MRI. We exploited an information theoretic approach such as Kullback-Leibler Divergence (KLD) for feature selection and ranking different texture features. We further incorporated the feature selection technique with segmentation method such as Expectation Maximization (EM) for segmentation of tumor T and non tumor (NT) tissues. In this work, we extend the two class KLD technique to multiclass for effectively selecting the best features for brain tumor (T), cyst (C) and non tumor (NT). We further obtain segmentation robustness for each tissue types by computing Bay's posterior probabilities and corresponding number of pixels for each tissue segments in MRI patient images. We evaluate improved tumor segmentation robustness using different similarity metric for 5 patients in T1, T2 and FLAIR modalities.

Cognitive memory and mapping in a brain-like system for robotic navigation.

PubMed

Tang, Huajin; Huang, Weiwei; Narayanamoorthy, Aditya; Yan, Rui

2017-03-01

Electrophysiological studies in animals may provide a great insight into developing brain-like models of spatial cognition for robots. These studies suggest that the spatial ability of animals requires proper functioning of the hippocampus and the entorhinal cortex (EC). The involvement of the hippocampus in spatial cognition has been extensively studied, both in animal as well as in theoretical studies, such as in the brain-based models by Edelman and colleagues. In this work, we extend these earlier models, with a particular focus on the spatial coding properties of the EC and how it functions as an interface between the hippocampus and the neocortex, as proposed by previous work. By realizing the cognitive memory and mapping functions of the hippocampus and the EC, respectively, we develop a neurobiologically-inspired system to enable a mobile robot to perform task-based navigation in a maze environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dynamic steady-state analysis of crack propagation in rubber-like solids using an extended finite element method

NASA Astrophysics Data System (ADS)

Kroon, Martin

2012-01-01

In the present study, a computational framework for studying high-speed crack growth in rubber-like solids under conditions of plane stress and steady-state is proposed. Effects of inertia, viscoelasticity and finite strains are included. The main purpose of the study is to examine the contribution of viscoelastic dissipation to the total work of fracture required to propagate a crack in a rubber-like solid. The computational framework builds upon a previous work by the present author (Kroon in Int J Fract 169:49-60, 2011). The model was fully able to predict experimental results in terms of the local surface energy at the crack tip and the total energy release rate at different crack speeds. The predicted distributions of stress and dissipation around the propagating crack tip are presented. The predicted crack tip profiles also agree qualitatively with experimental findings.

Representing the Quantum Object Through Fiction in Teaching. The Ontological Contribution of Gamow's Narrative as Part of an Introduction to Quantum Physics

NASA Astrophysics Data System (ADS)

Héraud, Jean-Loup; Lautesse, Philippe; Ferlin, Fabrice; Chabot, Hugues

2017-05-01

Our work extends a previous study of epistemological presuppositions in teaching quantum physics in upper scientific secondary school in France. Here, the problematic reference of quantum theory's concepts is treated at the ontological level (the counterintuitive nature of quantum objects). We consider the approach of using narratives describing possible alternative worlds to address the issue. These possible worlds are based on the counterfactual logic developed in the work of D. Lewis. We will show that the narratives written by G. Gamow describe such possible worlds. Some parts of these narratives are found in textbooks in France. These worlds are governed by laws similar to but importantly different from those in our real world. They allow us to materialize properties inaccessible to everyday experience. In this sense, these fiction stories make ontological propositions concerning the nature and structure of the fundamental elements of our physical universe.

Lithospheric Thickness on Venus from Magellan Gravity and Topography

NASA Technical Reports Server (NTRS)

Johnson, C. L.

2005-01-01

This final report summarizes work carried out during my PGG funding for the period 3/1/02-2/28/05. Research under this award has focused on the areas described below and is represented in the publications list, invited departmental lectures and presentations at professional meetings. The grant has provided partial support for 1 graduate student, Renee Bulow, and provided 1 month per year of my summer salary. The linking theme of the research performed under this award is the manifestation of the thermal history of terrestrial planetary bodies through the existence and evolution of internally-generated magnetic fields (martian magnetism research, and beginnings of lunar magnetism research), mantle dynamical processes and their resulting surface expression (studies of Venusian coronae task) and the crust and upper mantle structure of a planetary body (lunar seismic structure task). The investigations build upon and extend my previous work supported by the PGG program.

A Highly Resolved Large-Eddy Simulation of a Wind Turbine using an Actuator Line Model with Optimal Body Force Projection

DOE PAGES

Martinez-Tossas, Luis A.; Churchfield, Matthew J.; Meneveau, Charles

2016-10-03

When representing the blade aerodynamics with rotating actuator lines, the computed forces have to be projected back to the CFD flow field as a volumetric body force. That has been done in the past with a geometrically simple uniform three-dimensional Gaussian at each point along the blade. Here, we argue that the body force can be shaped in a way that better predicts the blade local flow field, the blade load distribution, and the formation of the tip/root vortices. In previous work, we have determined the optimal scales of circular and elliptical Gaussian kernels that best reproduce the local flowmore » field in two-dimensions. Lastly, in this work we extend the analysis and applications by considering the full three-dimensional blade to test our hypothesis in a highly resolved Large Eddy Simulation.« less

Clinical data interoperability based on archetype transformation.

PubMed

Costa, Catalina Martínez; Menárguez-Tortosa, Marcos; Fernández-Breis, Jesualdo Tomás

2011-10-01

The semantic interoperability between health information systems is a major challenge to improve the quality of clinical practice and patient safety. In recent years many projects have faced this problem and provided solutions based on specific standards and technologies in order to satisfy the needs of a particular scenario. Most of such solutions cannot be easily adapted to new scenarios, thus more global solutions are needed. In this work, we have focused on the semantic interoperability of electronic healthcare records standards based on the dual model architecture and we have developed a solution that has been applied to ISO 13606 and openEHR. The technological infrastructure combines reference models, archetypes and ontologies, with the support of Model-driven Engineering techniques. For this purpose, the interoperability infrastructure developed in previous work by our group has been reused and extended to cover the requirements of data transformation. Copyright © 2011 Elsevier Inc. All rights reserved.

Multi-scale Imaging of Cellular and Sub-cellular Structures using Scanning Probe Recognition Microscopy.

NASA Astrophysics Data System (ADS)

Chen, Q.; Rice, A. F.

2005-03-01

Scanning Probe Recognition Microscopy is a new scanning probe capability under development within our group to reliably return to and directly interact with a specific nanobiological feature of interest. In previous work, we have successfully recognized and classified tubular versus globular biological objects from experimental atomic force microscope images using a method based on normalized central moments [ref. 1]. In this paper we extend this work to include recognition schemes appropriate for cellular and sub-cellular structures. Globular cells containing tubular actin filaments are under investigation. Thus there are differences in external/internal shapes and scales. Continuous Wavelet Transform with a differential Gaussian mother wavelet is employed for multi- scale analysis. [ref. 1] Q. Chen, V. Ayres and L. Udpa, ``Biological Investigation Using Scanning Probe Recognition Microscopy,'' Proceedings 3rd IEEE Conference on Nanotechnology, vol. 2, p 863-865 (2003).

Semi-supervised learning via regularized boosting working on multiple semi-supervised assumptions.

PubMed

Chen, Ke; Wang, Shihai

2011-01-01

Semi-supervised learning concerns the problem of learning in the presence of labeled and unlabeled data. Several boosting algorithms have been extended to semi-supervised learning with various strategies. To our knowledge, however, none of them takes all three semi-supervised assumptions, i.e., smoothness, cluster, and manifold assumptions, together into account during boosting learning. In this paper, we propose a novel cost functional consisting of the margin cost on labeled data and the regularization penalty on unlabeled data based on three fundamental semi-supervised assumptions. Thus, minimizing our proposed cost functional with a greedy yet stagewise functional optimization procedure leads to a generic boosting framework for semi-supervised learning. Extensive experiments demonstrate that our algorithm yields favorite results for benchmark and real-world classification tasks in comparison to state-of-the-art semi-supervised learning algorithms, including newly developed boosting algorithms. Finally, we discuss relevant issues and relate our algorithm to the previous work.

Time-resolved electric force microscopy of charge traps in polycrystalline pentacene films

NASA Astrophysics Data System (ADS)

Jaquith, Michael; Muller, Erik; Marohn, John

2006-03-01

The microscopic mechanisms by which charges trap in organic electronic materials are poorly understood. Muller and Marohn recently showed that electric force microscopy (EFM) can be used to image trapped charge in working pentacene thin-film transistors [E. M. Muller et al, Adv. Mater. 17 1410 (2005)]. We have extended their work by imaging trapped charge in pentacene films with much larger grains. In contrast to the previous study in which charge was found to trap inhomogeneously throughout the transistor gap, we find microscopic evidence for a new trapping mechanism in which charges trap predominantly at the pentacene/metal interface in large-grained devices. We have also made localized measurements of the trap growth over time by performing pulsed-gate EFM experiments. Integrated-rate kinetics data supports a charge trap mechanism which is second order in holes, e.g., holes trap in pairs, although the charge-trapping rate appears to depend on gate voltage.

Evaluation of the William S. Hall Psychiatric Institute Clinical Psychology Internship: a replication and extension.

PubMed

Stader, Sandra R; Myers, DeRosset; Forand, Angela Q; Holmes, George R; McNulty, George F; Frey, Linda; Bolton, Staci S

2010-12-01

This study extends three earlier investigations involving participants who completed their predoctoral clinical psychology internship at the William S. Hall Psychiatric Institute. Intern graduates (N = 37) evaluated how effectively their internship training prepared them for seven aspects of their current work as practicing psychologists. Participants also rated the relevancy of 24 different internship training experiences to their current work and how much these experiences contributed to their development as clinical psychologists. The present study, in conjunction with the three previous studies, covers most of the 40-year period since the inception of the internship program. Analysis of the current data indicates the internship has improved over time and was deemed an exceptional training experience by its graduates. Findings may be of particular interest to internship directors and faculty interested in improving their training program and those who plan to conduct a self-study to maintain their accreditation for clinical psychology internship.

Relaxation rates of low-field gas-phase ^129Xe storage cells

NASA Astrophysics Data System (ADS)

Limes, Mark; Saam, Brian

2010-10-01

A study of longitudinal nuclear relaxation rates T1 of ^129Xe and Xe-N2 mixtures in a magnetic field of 3.8 mT is presented. In this regime, intrinsic spin relaxation is dominated by the intramolecular spin-rotation interaction due to persistent xenon dimers, a mechanism that can be quelled by introducing large amounts of N2 into the storage cell. Extrinsic spin relaxation is dominated by the wall-relaxation rate, which is the primary quantity of interest for the various low-field storage cells and coatings that we have tested. Previous group work has shown that extremely long gas-phase relaxation times T1 can be obtained, but only at large magnetic fields and low xenon densities. The current work is motivated by the practical benefits of retaining hyperpolarized ^129Xe for extended periods of time in a small magnetic field.

Adaptive Working Memory Training Reduces the Negative Impact of Anxiety on Competitive Motor Performance.

PubMed

Ducrocq, Emmanuel; Wilson, Mark; Smith, Tim J; Derakshan, Nazanin

2017-12-01

Optimum levels of attentional control are essential to prevent athletes from experiencing performance breakdowns under pressure. The current study explored whether training attentional control using the adaptive dual n-back paradigm, designed to directly target processing efficiency of the main executive functions of working memory (WM), would result in transferrable effects on sports performance outcomes. A total of 30 tennis players were allocated to an adaptive WM training or active control group and underwent 10 days of training. Measures of WM capacity as well as performance and objective gaze indices of attentional control in a tennis volley task were assessed in low- and high-pressure posttraining conditions. Results revealed significant benefits of training on WM capacity, quiet eye offset, and tennis performance in the high-pressure condition. Our results confirm and extend previous findings supporting the transfer of cognitive training benefits to objective measures of sports performance under pressure.

A Highly Resolved Large-Eddy Simulation of a Wind Turbine using an Actuator Line Model with Optimal Body Force Projection

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

Martinez-Tossas, Luis A.; Churchfield, Matthew J.; Meneveau, Charles

When representing the blade aerodynamics with rotating actuator lines, the computed forces have to be projected back to the CFD flow field as a volumetric body force. That has been done in the past with a geometrically simple uniform three-dimensional Gaussian at each point along the blade. Here, we argue that the body force can be shaped in a way that better predicts the blade local flow field, the blade load distribution, and the formation of the tip/root vortices. In previous work, we have determined the optimal scales of circular and elliptical Gaussian kernels that best reproduce the local flowmore » field in two-dimensions. Lastly, in this work we extend the analysis and applications by considering the full three-dimensional blade to test our hypothesis in a highly resolved Large Eddy Simulation.« less

Working memory and social functioning in children.

PubMed

McQuade, Julia D; Murray-Close, Dianna; Shoulberg, Erin K; Hoza, Betsy

2013-07-01

This study extends previous research and examines whether working memory (WM) is associated with multiple measures of concurrent social functioning (peer rejection, overall social competence, relational aggression, physical aggression, and conflict resolutions skills) in typically developing fourth- and fifth-grade children (N=116). Poor central executive WM was associated with both broad social impairments (peer rejection and poor overall social competence) and specific social impairments (physical aggression, relational aggression, and impaired conflict resolution skills); poor verbal storage was associated only with greater peer rejection, and spatial storage was not associated with any measures of social impairment. Analyses also examined whether specific impairments in aggressive behavior and conflict resolution skills mediated the association between central executive and broad measures of social functioning. Greater physical aggression and impaired conflict resolution skills were both significant mediators; relational aggression was not. Implications for theory and future research are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Human area MT+ shows load-dependent activation during working memory maintenance with continuously morphing stimulation.

PubMed

Galashan, Daniela; Fehr, Thorsten; Kreiter, Andreas K; Herrmann, Manfred

2014-07-11

Initially, human area MT+ was considered a visual area solely processing motion information but further research has shown that it is also involved in various different cognitive operations, such as working memory tasks requiring motion-related information to be maintained or cognitive tasks with implied or expected motion.In the present fMRI study in humans, we focused on MT+ modulation during working memory maintenance using a dynamic shape-tracking working memory task with no motion-related working memory content. Working memory load was systematically varied using complex and simple stimulus material and parametrically increasing retention periods. Activation patterns for the difference between retention of complex and simple memorized stimuli were examined in order to preclude that the reported effects are caused by differences in retrieval. Conjunction analysis over all delay durations for the maintenance of complex versus simple stimuli demonstrated a wide-spread activation pattern. Percent signal change (PSC) in area MT+ revealed a pattern with higher values for the maintenance of complex shapes compared to the retention of a simple circle and with higher values for increasing delay durations. The present data extend previous knowledge by demonstrating that visual area MT+ presents a brain activity pattern usually found in brain regions that are actively involved in working memory maintenance.

Intact working memory in the absence of forebrain neuronal glycine transporter 1

PubMed Central

Dubroqua, Sylvain; Serrano, Lucas; Boison, Detlev; Feldon, Joram; Gargiulo, Pascual A.; Yee, Benjamin K.

2012-01-01

Glycine transporter 1 (GlyT1) is a potential pharmacological target to ameliorate memory deficits attributable to N-methyl-d-aspartate receptor (NMDAR) hypofunction. Disruption of glycine-reuptake near excitatory synapses is expected to enhance NMDAR function by increasing glycine-B site occupancy. Genetic models with conditional GlyT1 deletion restricted to forebrain neurons have yielded several promising promnesic effects, yet its impact on working memory function remains essentially unanswered because a previous attempt had yielded un-interpretable outcomes. The present study clarified this important outstanding lacuna using a within-subject multi-paradigm approach. Here, a consistent lack of effects was convincingly demonstrated across three working memory test paradigms – the radial arm maze, the cheeseboard maze, and the water maze. These null outcomes contrasted with the phenotype of enhanced working memory performance seen in mutant mice with GlyT1 deletion extended to cortical/hippocampal glial cells. It follows that glial-based GlyT1 might be more closely linked to the modulation of working memory function, and raises the possibility that neuronal and glial GlyT1 may regulate cognitive functions via dissociable mechanisms. PMID:22342492

A New Class of Macrocyclic Chiral Selectors for Stereochemical Analysis

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

NONE

1999-03-11

This report summarizes the work accomplished in the authors laboratories over the previous three years. During the funding period they have had 23 monographs published or in press, 1 book chapter, 1 patent issued and have delivered 28 invited seminars or plenary lectures on DOE sponsored research. This report covers the work that has been published (or accepted). The most notable aspect of this work involves the successful development and understanding of a new class of fused macrocyclic compounds as pseudophases and selectors in high performance separations (including high performance liquid chromatography, HPLC; capillary electrophoresis, CE; and thin layer chromatography,more » TLC). They have considerably extended their chiral biomarker work from amber to crude oil and coal. In the process of doing this we've developed several novel separation approaches. They finished their work on the new GSC-PLOT column which is now being used by researchers world-wide for the analysis of gases, light hydrocarbons and halocarbons. Finally, we completed basic studies on immobilizing a cyclodextrin/oligosiloxane hybrid on the wall of fused silica, as well as a basic study on the separation behavior of buckminster fullerene and higher fullerenes.« less

Modeling Reconnection-Driven Solar Polar Jets with Gravity and Wind

NASA Astrophysics Data System (ADS)

Karpen, Judith T.; DeVore, C. R.; Antiochos, S. K.

2013-07-01

Solar polar jets are dynamic, narrow, radially extended structures observed in EUV emission. They have been found to originate within the open magnetic field of coronal holes in “anemone” regions, which are generally accepted to be intrusions of opposite polarity. The associated embedded-dipole topology consists of a spine line emanating from a null point atop a dome-shaped fan surface. Previous work (Pariat et al. 2009, 2010) has validated the idea that magnetic free energy stored on twisted closed field lines within the fan surface can be released explosively by the onset of fast reconnection between the highly stressed closed field inside the null and the unstressed open field outside (Antiochos 1996). The simulations showed that a dense jet comprising a nonlinear, torsional Alfven wave is ejected into the outer corona on the newly reconnected open field lines. While proving the principle of the basic model, those simulations neglected the important effects of gravity, the solar wind, and an expanding spherical geometry. We introduce those additional physical processes in new simulations of reconnection-driven jets, to determine whether the model remains robust in the resulting more realistic setting, and to begin establishing the signatures of the jets in the inner heliosphere for comparison with observations. Initial results demonstrate explosive energy release and a jet in the low corona very much like that in the earlier Cartesian, gravity-free, static-atmosphere runs. We report our analysis of the results, their comparison with previous work, and their implications for observations. This work was supported by NASA’s LWS TR&T program.Abstract (2,250 Maximum Characters): Solar polar jets are dynamic, narrow, radially extended structures observed in EUV emission. They have been found to originate within the open magnetic field of coronal holes in “anemone” regions, which are generally accepted to be intrusions of opposite polarity. The associated embedded-dipole topology consists of a spine line emanating from a null point atop a dome-shaped fan surface. Previous work (Pariat et al. 2009, 2010) has validated the idea that magnetic free energy stored on twisted closed field lines within the fan surface can be released explosively by the onset of fast reconnection between the highly stressed closed field inside the null and the unstressed open field outside (Antiochos 1996). The simulations showed that a dense jet comprising a nonlinear, torsional Alfven wave is ejected into the outer corona on the newly reconnected open field lines. While proving the principle of the basic model, those simulations neglected the important effects of gravity, the solar wind, and an expanding spherical geometry. We introduce those additional physical processes in new simulations of reconnection-driven jets, to determine whether the model remains robust in the resulting more realistic setting, and to begin establishing the signatures of the jets in the inner heliosphere for comparison with observations. Initial results demonstrate explosive energy release and a jet in the low corona very much like that in the earlier Cartesian, gravity-free, static-atmosphere runs. We report our analysis of the results, their comparison with previous work, and their implications for observations. This work was supported by NASA’s LWS TR&T program.

PFMCal : Photonic force microscopy calibration extended for its application in high-frequency microrheology

NASA Astrophysics Data System (ADS)

Butykai, A.; Domínguez-García, P.; Mor, F. M.; Gaál, R.; Forró, L.; Jeney, S.

2017-11-01

The present document is an update of the previously published MatLab code for the calibration of optical tweezers in the high-resolution detection of the Brownian motion of non-spherical probes [1]. In this instance, an alternative version of the original code, based on the same physical theory [2], but focused on the automation of the calibration of measurements using spherical probes, is outlined. The new added code is useful for high-frequency microrheology studies, where the probe radius is known but the viscosity of the surrounding fluid maybe not. This extended calibration methodology is automatic, without the need of a user's interface. A code for calibration by means of thermal noise analysis [3] is also included; this is a method that can be applied when using viscoelastic fluids if the trap stiffness is previously estimated [4]. The new code can be executed in MatLab and using GNU Octave. Program Files doi:http://dx.doi.org/10.17632/s59f3gz729.1 Licensing provisions: GPLv3 Programming language: MatLab 2016a (MathWorks Inc.) and GNU Octave 4.0 Operating system: Linux and Windows. Supplementary material: A new document README.pdf includes basic running instructions for the new code. Journal reference of previous version: Computer Physics Communications, 196 (2015) 599 Does the new version supersede the previous version?: No. It adds alternative but compatible code while providing similar calibration factors. Nature of problem (approx. 50-250 words): The original code uses a MatLab-provided user's interface, which is not available in GNU Octave, and cannot be used outside of a proprietary software as MatLab. Besides, the process of calibration when using spherical probes needs an automatic method when calibrating big amounts of different data focused to microrheology. Solution method (approx. 50-250 words): The new code can be executed in the latest version of MatLab and using GNU Octave, a free and open-source alternative to MatLab. This code generates an automatic calibration process which requires only to write the input data in the main script. Additionally, we include a calibration method based on thermal noise statistics, which can be used with viscoelastic fluids if the trap stiffness is previously estimated. Reasons for the new version: This version extends the functionality of PFMCal for the particular case of spherical probes and unknown fluid viscosities. The extended code is automatic, works in different operating systems and it is compatible with GNU Octave. Summary of revisions: The original MatLab program in the previous version, which is executed by PFMCal.m, is not changed. Here, we have added two additional main archives named PFMCal_auto.m and PFMCal_histo.m, which implement automatic calculations of the calibration process and calibration through Boltzmann statistics, respectively. The process of calibration using this code for spherical beads is described in the README.pdf file provided in the new code submission. Here, we obtain different calibration factors, β (given in μm/V), according to [2], related to two statistical quantities: the mean-squared displacement (MSD), βMSD, and the velocity autocorrelation function (VAF), βVAF. Using that methodology, the trap stiffness, k, and the zero-shear viscosity of the fluid, η, can be calculated if the value of the particle's radius, a, is previously known. For comparison, we include in the extended code the method of calibration using the corner frequency of the power-spectral density (PSD) [5], providing a calibration factor βPSD. Besides, with the prior estimation of the trap stiffness, along with the known value of the particle's radius, we can use thermal noise statistics to obtain calibration factors, β, according to the quadratic form of the optical potential, βE, and related to the Gaussian distribution of the bead's positions, βσ2. This method has been demonstrated to be applicable to the calibration of optical tweezers when using non-Newtonian viscoelastic polymeric liquids [4]. An example of the results using this calibration process is summarized in Table 1. Using the data provided in the new code submission, for water and acetone fluids, we calculate all the calibration factors by using the original PFMCal.m and by the new non-GUI code PFMCal_auto.m and PFMCal_histo.m. Regarding the new code, PFMCal_auto.m returns η, k, βMSD, βVAF and βPSD, while PFMCal_histo.m provides βσ2 and βE. Table 1 shows how we obtain the expected viscosity of the two fluids at this temperature and how the different methods provide good agreement between trap stiffnesses and calibration factors. Additional comments including Restrictions and Unusual features (approx. 50-250 words): The original code, PFMCal.m, runs under MatLab using the Statistics Toolbox. The extended code, PFMCal_auto.m and PFMCal_histo.m, can be executed without modification using MatLab or GNU Octave. The code has been tested in Linux and Windows operating systems.

Extended work availability and its relation with start-of-day mood and cortisol.

PubMed

Dettmers, Jan; Vahle-Hinz, Tim; Bamberg, Eva; Friedrich, Niklas; Keller, Monika

2016-01-01

The opportunity to work at any time and place, which is facilitated by mobile communication technologies, reinforces employer expectations that employees are available for work beyond regular work hours. This study investigates the relation of daily extended work availability with psychological and physiological well-being and the mediating role of recovery experiences. We hypothesized that recovery is limited under conditions of extended work availability, which may impair well-being. A sample of 132 individuals from 13 organizations provided daily survey measures over a period of 4 days during which they were required to be available during nonworking hours and 4 days during which they were not required to be available. A subsample of 51 persons provided morning cortisol levels in addition to the survey data. The analysis of within-person processes using multilevel structural equation modeling revealed significant effects of extended work availability on the daily start-of-day mood and cortisol awakening response. Mediation analysis revealed that the recovery experience of control over off-job activities mediated the observed relationship with start-of-day mood but not the relationship with the cortisol awakening response. The results demonstrate that nonwork hours during which employees are required to remain available for work cannot be considered leisure time because employees' control over their activities is constrained and their recovery from work is restricted. (c) 2016 APA, all rights reserved).

The AU Mic Debris Disk: Far-infrared and Submillimeter Resolved Imaging

NASA Astrophysics Data System (ADS)

Matthews, Brenda C.; Kennedy, Grant; Sibthorpe, Bruce; Holland, Wayne; Booth, Mark; Kalas, Paul; MacGregor, Meredith; Wilner, David; Vandenbussche, Bart; Olofsson, Göran; Blommaert, Joris; Brandeker, Alexis; Dent, W. R. F.; de Vries, Bernard L.; Di Francesco, James; Fridlund, Malcolm; Graham, James R.; Greaves, Jane; Heras, Ana M.; Hogerheijde, Michiel; Ivison, R. J.; Pantin, Eric; Pilbratt, Göran L.

2015-10-01

We present far-infrared and submillimeter maps from the Herschel Space Observatory and the James Clerk Maxwell Telescope of the debris disk host star AU Microscopii. Disk emission is detected at 70, 160, 250, 350, 450, 500, and 850 μm. The disk is resolved at 70, 160, and 450 μm. In addition to the planetesimal belt, we detect thermal emission from AU Mic’s halo for the first time. In contrast to the scattered light images, no asymmetries are evident in the disk. The fractional luminosity of the disk is 3.9× {10}-4 and its milimeter-grain dust mass is 0.01 {M}\\oplus (±20%). We create a simple spatial model that reconciles the disk spectral energy distribution as a blackbody of 53 ± 2 K (a composite of 39 and 50 K components) and the presence of small (non-blackbody) grains which populate the extended halo. The best-fit model is consistent with the “birth ring” model explored in earlier works, i.e., an edge-on dust belt extending from 8.8 to 40 AU, but with an additional halo component with an {r}-1.5 surface density profile extending to the limits of sensitivity (140 AU). We confirm that AU Mic does not exert enough radiation force to blow out grains. For stellar mass-loss rates of 10-100 times solar, compact (zero porosity) grains can only be removed if they are very small; consistently with previous work, if the porosity is 0.9, then grains approaching 0.1 μm can be removed via corpuscular forces (i.e., the stellar wind).

An Algorithm to Automatically Generate the Combinatorial Orbit Counting Equations

PubMed Central

Melckenbeeck, Ine; Audenaert, Pieter; Michoel, Tom; Colle, Didier; Pickavet, Mario

2016-01-01

Graphlets are small subgraphs, usually containing up to five vertices, that can be found in a larger graph. Identification of the graphlets that a vertex in an explored graph touches can provide useful information about the local structure of the graph around that vertex. Actually finding all graphlets in a large graph can be time-consuming, however. As the graphlets grow in size, more different graphlets emerge and the time needed to find each graphlet also scales up. If it is not needed to find each instance of each graphlet, but knowing the number of graphlets touching each node of the graph suffices, the problem is less hard. Previous research shows a way to simplify counting the graphlets: instead of looking for the graphlets needed, smaller graphlets are searched, as well as the number of common neighbors of vertices. Solving a system of equations then gives the number of times a vertex is part of each graphlet of the desired size. However, until now, equations only exist to count graphlets with 4 or 5 nodes. In this paper, two new techniques are presented. The first allows to generate the equations needed in an automatic way. This eliminates the tedious work needed to do so manually each time an extra node is added to the graphlets. The technique is independent on the number of nodes in the graphlets and can thus be used to count larger graphlets than previously possible. The second technique gives all graphlets a unique ordering which is easily extended to name graphlets of any size. Both techniques were used to generate equations to count graphlets with 4, 5 and 6 vertices, which extends all previous results. Code can be found at https://github.com/IneMelckenbeeck/equation-generator and https://github.com/IneMelckenbeeck/graphlet-naming. PMID:26797021

DETERMINING THE NATURE OF THE EXTENDED H I STRUCTURE AROUND LITTLE THINGS DWARF GALAXY NGC 1569

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

Johnson, Megan, E-mail: mjohnson@nrao.edu; National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24915

2013-06-15

This work presents an extended, neutral hydrogen emission map around Magellanic-type dwarf irregular galaxy (dIm) NGC 1569. In the spring of 2010, the Robert C. Byrd Green Bank Telescope was used to map a 9 Degree-Sign Multiplication-Sign 2 Degree-Sign region in H I line emission that includes NGC 1569 and IC 342 as well as two other dwarf galaxies. The primary objective for these observations was to search for structures potentially connecting NGC 1569 with IC 342 group members in order to trace previous interactions and thus, provide an explanation for the starburst and peculiar kinematics prevalent in NGC 1569.more » A large, half-degree diameter H I cloud was detected that shares the same position and velocity as NGC 1569. Also, two long structures were discovered that are reminiscent of intergalactic filaments extending out in a V-shaped manner from NGC 1569 toward UGCA 92, a nearby dwarf galaxy. These filamentary structures extend for about 1. Degree-Sign 5, which is 77 kpc at NGC 1569. There is a continuous velocity succession with the 0. Degree-Sign 5 H I cloud, filaments, and main body of the galaxy. The 0. Degree-Sign 5 H I cloud and filamentary structures may be foreground Milky Way, but are suggestive as possible remnants of an interaction between NGC 1569 and UGCA 92. The data also show two tidal tails extending from UGCA 86 and IC 342, respectively. These structures may be part of a continuous H I bridge but more data are needed to determine if this is the case.« less

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

Beidler, M. T.; Cassak, P. A.; Jardin, S. C.

We diagnose local properties of magnetic reconnection during a sawtooth crash employing the three-dimensional toroidal, extended-magnetohydrodynamic (MHD) code M3D-C 1. To do so, we sample simulation data in the plane in which reconnection occurs, the plane perpendicular to the helical (m, n) = (1, 1) mode at the q = 1 surface, where m and n are the poloidal and toroidal mode numbers and q is the safety factor. We study the nonlinear evolution of a particular test equilibrium in a non-reduced field representation using both resistive-MHD and extended-MHD models. We find growth rates for the extended-MHD reconnection process exhibitmore » a nonlinear acceleration and greatly exceed that of the resistive-MHD model, as is expected from previous experimental, theoretical, and computational work. We compare the properties of reconnection in the two simulations, revealing the reconnecting current sheets are locally different in the two models and we present the first observation of the quadrupole out-of-plane Hall magnetic field that appears during extended-MHD reconnection in a 3D toroidal simulation (but not in resistive-MHD). We also explore the dependence on toroidal angle of the properties of reconnection as viewed in the plane perpendicular to the helical magnetic field, finding qualitative and quantitative effects due to changes in the symmetry of the reconnection process. Furthermore, this study is potentially important for a wide range of magnetically confined fusion applications, from confirming simulations with extended-MHD effects are sufficiently resolved to describe reconnection, to quantifying local reconnection rates for purposes of understanding and predicting transport, not only at the q = 1 rational surface for sawteeth, but also at higher order rational surfaces that play a role in disruptions and edge-confinement degradation.« less

An extension to artifact-free projection overlaps

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

Lin, Jianyu, E-mail: jianyulin@hotmail.com

2015-05-15

Purpose: In multipinhole single photon emission computed tomography, the overlapping of projections has been used to increase sensitivity. Avoiding artifacts in the reconstructed image associated with projection overlaps (multiplexing) is a critical issue. In our previous report, two types of artifact-free projection overlaps, i.e., projection overlaps that do not lead to artifacts in the reconstructed image, were formally defined and proved, and were validated via simulations. In this work, a new proposition is introduced to extend the previously defined type-II artifact-free projection overlaps so that a broader range of artifact-free overlaps is accommodated. One practical purpose of the new extensionmore » is to design a baffle window multipinhole system with artifact-free projection overlaps. Methods: First, the extended type-II artifact-free overlap was theoretically defined and proved. The new proposition accommodates the situation where the extended type-II artifact-free projection overlaps can be produced with incorrectly reconstructed portions in the reconstructed image. Next, to validate the theory, the extended-type-II artifact-free overlaps were employed in designing the multiplexing multipinhole spiral orbit imaging systems with a baffle window. Numerical validations were performed via simulations, where the corresponding 1-pinhole nonmultiplexing reconstruction results were used as the benchmark for artifact-free reconstructions. The mean square error (MSE) was the metric used for comparisons of noise-free reconstructed images. Noisy reconstructions were also performed as part of the validations. Results: Simulation results show that for noise-free reconstructions, the MSEs of the reconstructed images of the artifact-free multiplexing systems are very similar to those of the corresponding 1-pinhole systems. No artifacts were observed in the reconstructed images. Therefore, the testing results for artifact-free multiplexing systems designed using the extended type-II artifact-free overlaps numerically validated the developed theory. Conclusions: First, the extension itself is of theoretical importance because it broadens the selection range for optimizing multiplexing multipinhole designs. Second, the extension has an immediate application: using a baffle window to design a special spiral orbit multipinhole imaging system with projection overlaps in the orbit axial direction. Such an artifact-free baffle window design makes it possible for us to image any axial portion of interest of a long object with projection overlaps to increase sensitivity.« less

Work stressors and partner social undermining: Comparing negative affect and psychological detachment as mechanisms.

PubMed

Meier, Laurenz L; Cho, Eunae

2018-05-14

With the mounting evidence that employees' work experiences spill over into the family domain and cross over to family members, it is important to understand the underlying mechanism through which work experiences affect the family domain and what factors may alleviate the adverse impact of work stress. Expanding previous research that mainly focused on the affect-based mechanism (negative affect), the present research investigated a resource-based mechanism (psychological detachment from work) in the relationship linking two work stressors (high workload and workplace incivility) with social undermining toward the partner at home. We also explored the relative strength of the mediating effects of the two mechanisms. In addition, we tested whether relationship satisfaction moderates the proposed effect of detachment on partner undermining. We tested these research questions using two studies with differing designs: a five-wave longitudinal study (N = 470) and a multisource study (N = 131). The results suggest that stressful work experiences affect the family domain via lack of detachment as well as negative affect, that the two pathways have comparable strength, and that high relationship satisfaction mitigates the negative effect of lack of detachment on partner undermining. In sum, this research extends the spillover-crossover model by establishing that poor psychological detachment from work during leisure time is an additional mechanism that links work and family. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Nationwide Buildings Energy Research enabled through an integrated Data Intensive Scientific Workflow and Advanced Analysis Environment

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

Kleese van Dam, Kerstin; Lansing, Carina S.; Elsethagen, Todd O.

2014-01-28

Modern workflow systems enable scientists to run ensemble simulations at unprecedented scales and levels of complexity, allowing them to study system sizes previously impossible to achieve, due to the inherent resource requirements needed for the modeling work. However as a result of these new capabilities the science teams suddenly also face unprecedented data volumes that they are unable to analyze with their existing tools and methodologies in a timely fashion. In this paper we will describe the ongoing development work to create an integrated data intensive scientific workflow and analysis environment that offers researchers the ability to easily create andmore » execute complex simulation studies and provides them with different scalable methods to analyze the resulting data volumes. The integration of simulation and analysis environments is hereby not only a question of ease of use, but supports fundamental functions in the correlated analysis of simulation input, execution details and derived results for multi-variant, complex studies. To this end the team extended and integrated the existing capabilities of the Velo data management and analysis infrastructure, the MeDICi data intensive workflow system and RHIPE the R for Hadoop version of the well-known statistics package, as well as developing a new visual analytics interface for the result exploitation by multi-domain users. The capabilities of the new environment are demonstrated on a use case that focusses on the Pacific Northwest National Laboratory (PNNL) building energy team, showing how they were able to take their previously local scale simulations to a nationwide level by utilizing data intensive computing techniques not only for their modeling work, but also for the subsequent analysis of their modeling results. As part of the PNNL research initiative PRIMA (Platform for Regional Integrated Modeling and Analysis) the team performed an initial 3 year study of building energy demands for the US Eastern Interconnect domain, which they are now planning to extend to predict the demand for the complete century. The initial study raised their data demands from a few GBs to 400GB for the 3year study and expected tens of TBs for the full century.« less

Aspect-Oriented Monitoring of C Programs

NASA Technical Reports Server (NTRS)

Havelund, Klaus; VanWyk, Eric

2008-01-01

The paper presents current work on extending ASPECTC with state machines, resulting in a framework for aspect-oriented monitoring of C programs. Such a framework can be used for testing purposes, or it can be part of a fault protection strategy. The long term goal is to explore the synergy between the fields of runtime verification, focused on program monitoring, and aspect-oriented programming, focused on more general program development issues. The work is inspired by the observation that most work in this direction has been done for JAVA, partly due to the lack of easily accessible extensible compiler frameworks for C. The work is performed using the SILVER extensible attribute grammar compiler framework, in which C has been defined as a host language. Our work consists of extending C with ASPECTC, and subsequently to extend ASPECTC with state machines.

Classical conditioning of proboscis extension in harnessed Africanized honey bee queens (Apis mellifera L.).

PubMed

Aquino, Italo S; Abramson, Charles I; Soares, Ademilson E E; Fernandes, Andrea Cardoso; Benbassat, Danny

2004-06-01

Experiments are reported on learning in virgin Africanized honey bee queens (Apis mellifera L.). Queens restrained in a "Pavlovian harness" received a pairing of hexanal odor with a 1.8-M feeding of sucrose solution. Compared to explicitly unpaired controls, acquisition was rapid in reaching about 90%. Acquisition was also rapid in queens receiving an unconditioned stimulus of "bee candy" or an unconditioned stimulus administered by worker bees. During extinction the conditioned response declines. The steepest decline was observed in queens receiving an unconditioned stimulus of bee candy. These findings extend previous work on learning of Afrianized honey bee workers to a population of queen bees.

The application of prototype point processes for the summary and description of California wildfires

USGS Publications Warehouse

Nichols, K.; Schoenberg, F.P.; Keeley, J.E.; Bray, A.; Diez, D.

2011-01-01

A method for summarizing repeated realizations of a space-time marked point process, known as prototyping, is discussed and applied to catalogues of wildfires in California. Prototype summaries are constructed for varying time intervals using California wildfire data from 1990 to 2006. Previous work on prototypes for temporal and space-time point processes is extended here to include methods for computing prototypes with marks and the incorporation of prototype summaries into hierarchical clustering algorithms, the latter of which is used to delineate fire seasons in California. Other results include summaries of patterns in the spatial-temporal distribution of wildfires within each wildfire season. ?? 2011 Blackwell Publishing Ltd.

A note on local BRST cohomology of Yang-Mills type theories with free Abelian factors

NASA Astrophysics Data System (ADS)

Barnich, Glenn; Boulanger, Nicolas

2018-05-01

We extend previous work on antifield dependent local Becchi-Rouet-Stora-Tyutin (BRST) cohomology for matter coupled gauge theories of Yang-Mills type to the case of gauge groups that involve free Abelian factors. More precisely, we first investigate in a model independent way how the dynamics enters the computation of the cohomology for a general class of Lagrangians in general spacetime dimensions. We then discuss explicit solutions in the case of specific models. Our analysis has implications for the structure of characteristic cohomology and for consistent deformations of the classical models, as well as for divergences/counterterms and for gauge anomalies that may appear during perturbative quantization.

Partition-free approach to open quantum systems in harmonic environments: An exact stochastic Liouville equation

NASA Astrophysics Data System (ADS)

McCaul, G. M. G.; Lorenz, C. D.; Kantorovich, L.

2017-03-01

We present a partition-free approach to the evolution of density matrices for open quantum systems coupled to a harmonic environment. The influence functional formalism combined with a two-time Hubbard-Stratonovich transformation allows us to derive a set of exact differential equations for the reduced density matrix of an open system, termed the extended stochastic Liouville-von Neumann equation. Our approach generalizes previous work based on Caldeira-Leggett models and a partitioned initial density matrix. This provides a simple, yet exact, closed-form description for the evolution of open systems from equilibriated initial conditions. The applicability of this model and the potential for numerical implementations are also discussed.