Differences in problem-solving between canid populations: Do domestication and lifetime experience affect persistence?

Science.gov (United States)

Brubaker, Lauren; Dasgupta, Sandipan; Bhattacharjee, Debottam; Bhadra, Anindita; Udell, Monique A R

2017-07-01

Past research has suggested that a variety of factors, phylogenetic and ontogenetic, play a role in how canines behave during problem-solving tasks and the degree to which the presence of a human influences their problem-solving behaviour. While comparisons between socialized wolves and domestic dogs have commonly been used to tease apart these predictive factors, in many cases a single dog population, often pets, have been used for these comparisons. Less is understood about how different populations of dogs may behave when compared with wolves, or with each other, during an independent problem-solving task. This experiment compared the independent persistence of four populations of canines (two groups of pet domestic dogs, a group of free-ranging domestic dogs, and human-socialized wolves) on an independent problem-solving task in the presence of an on looking human. Results showed that wolves persisted the most at the task while free-ranging dogs persisted the least. Free-ranging dogs gazed at the human experimenter for the longest durations during the task. While further research is needed to understand why these differences exist, this study demonstrates that dogs, even those living outside human homes as scavengers, show comparatively low levels of persistence when confronted with a solvable task in the presence of a human as well as significantly greater duration of human-directed gaze when compared with wolves.

Using animal models to overcome temporal, spatial and combinatorial challenges in HIV persistence research

DEFF Research Database (Denmark)

Denton, Paul W.; Søgaard, Ole Schmeltz; Tolstrup, Martin

2016-01-01

Research challenges associated with understanding HIV persistence during antiretroviral therapy can be categorized as temporal, spatial and combinatorial. Temporal research challenges relate to the timing of events during establishment and maintenance of HIV persistence. Spatial research challeng...... for directly addressing these research challenges. The aim of this manuscript is to provide a comprehensive review of these recent translational advances made in animal models of HIV persistence....... will improve our understanding of HIV persistence and move the field closer to achieving eradication of persistent HIV. Given that humanized mice and non-human primate HIV models permit rigorous control of experimental conditions, these models have been used extensively as in vivo research platforms...

Professional Role Confidence and Gendered Persistence in Engineering

OpenAIRE

Cech, Erin; Rubineau, Brian; Seron, Caroll; Silbey, Susan S.

2011-01-01

Social psychological research on gendered persistence in science, technology, engineering, and mathematics (STEM) professions is dominated by two explanations: women leave because they perceive their family plans to be at odds with demands of STEM careers, and women leave due to low self-assessment of their skills in STEM’s intellectual tasks, net of their performance. This study uses original panel data to examine behavioral and intentional persistence among students who enter an engineering...

Antiphospholipid Syndrome Clinical Research Task Force Report

NARCIS (Netherlands)

Erkan, D.; Derksen, R.; Levy, R.; Machin, S.; Ortel, T.; Pierangeli, S.; Roubey, R.; Lockshin, M.

The Antiphospholipid Syndrome (APS) Clinical Research Task Force (CRTF) was one of six Task Forces developed by the 13(th) International Congress on Antiphospholipid Antibodies (aPL) organization committee with the purpose of: a) evaluating the limitations of APS clinical research and developing

The effects of acute stress on the calibration of persistence.

Science.gov (United States)

Lempert, Karolina M; McGuire, Joseph T; Hazeltine, Danielle B; Phelps, Elizabeth A; Kable, Joseph W

2018-02-01

People frequently fail to wait for delayed rewards after choosing them. These preference reversals are sometimes thought to reflect self-control failure. Other times, however, continuing to wait for a delayed reward may be counterproductive (e.g., when reward timing uncertainty is high). Research has demonstrated that people can calibrate how long to wait for rewards in a given environment. Thus, the role of self-control might be to integrate information about the environment to flexibly adapt behavior, not merely to promote waiting. Here we tested effects of acute stress, which has been shown to tax control processes, on persistence, and the calibration of persistence, in young adult human participants. Half the participants (n = 60) performed a task in which persistence was optimal, and the other half (n = 60) performed a task in which it was optimal to quit waiting for reward soon after each trial began. Each participant completed the task either after cold pressor stress or no stress. Stress did not influence persistence or optimal calibration of persistence. Nevertheless, an exploratory analysis revealed an "inverted-U" relationship between cortisol increase and performance in the stress groups, suggesting that choosing the adaptive waiting policy may be facilitated with some stress and impaired with severe stress.

JV Task 6 - Coal Ash Resources Research Consortium Research

Energy Technology Data Exchange (ETDEWEB)

Debra Pflughoeft-Hassett; Tera Buckley; Bruce Dockter; Kurt Eylands; David Hassett; Loreal Heebink; Erick Zacher

2008-04-01

The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of coal combustion by-products (CCBs). CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program (JSRP), which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCB performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 1998 to 2007 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. CARRC topical reports were prepared on several completed tasks. Specific CARRC 1998B2007 accomplishments included: (1) Development of several ASTM International Standard Guides for CCB utilization applications. (2) Organization and presentation of training courses for CCB professionals and teachers. (3) Development of online resources including the Coal Ash Resource Center, Ash from Biomass in Coal (ABC) of cocombustion ash characteristics, and the Buyer's Guide to Coal-Ash Containing Products. In addition

The effects of stimulus modality and task integrality: Predicting dual-task performance and workload from single-task levels

Science.gov (United States)

Hart, S. G.; Shively, R. J.; Vidulich, M. A.; Miller, R. C.

1986-01-01

The influence of stimulus modality and task difficulty on workload and performance was investigated. The goal was to quantify the cost (in terms of response time and experienced workload) incurred when essentially serial task components shared common elements (e.g., the response to one initiated the other) which could be accomplished in parallel. The experimental tasks were based on the Fittsberg paradigm; the solution to a SternBERG-type memory task determines which of two identical FITTS targets are acquired. Previous research suggested that such functionally integrated dual tasks are performed with substantially less workload and faster response times than would be predicted by suming single-task components when both are presented in the same stimulus modality (visual). The physical integration of task elements was varied (although their functional relationship remained the same) to determine whether dual-task facilitation would persist if task components were presented in different sensory modalities. Again, it was found that the cost of performing the two-stage task was considerably less than the sum of component single-task levels when both were presented visually. Less facilitation was found when task elements were presented in different sensory modalities. These results suggest the importance of distinguishing between concurrent tasks that complete for limited resources from those that beneficially share common resources when selecting the stimulus modalities for information displays.

Predictors of task-persistent and fear-avoiding behaviors in women with sexual pain disorders.

Science.gov (United States)

Brauer, Marieke; Lakeman, Mariëlle; van Lunsen, Rik; Laan, Ellen

2014-12-01

Dyspareunia and vaginismus are the most common sexual pain disorders (SPDs). Literature suggests that many women with dyspareunia continue with intercourse despite pain (task persistence), whereas many women with vaginismus avoid penetrative activities that may cause pain (fear avoidance). Both forms of sexual pain behavior may maintain or aggravate complaints. This study examined (i) whether women with SPD differ from pain-free controls in motives for sexual intercourse, sexual autonomy, maladaptive beliefs regarding vaginal penetration, and partner responses to pain; and (ii) which of these factors best predict whether women with SPD stop or continue painful intercourse (attempts). Women with superficial dyspareunia (n = 50), women with lifelong vaginismus (n = 20), and pain-free controls (n = 45) completed questionnaires. For Aim 1, the main outcome measures were (i) motives for intercourse; (ii) sexual autonomy; (iii) maladaptive beliefs regarding vaginal penetration; and (iv) partner responses to pain. For Aim 2, sexual pain behavior (to continue or discontinue with painful intercourse) was the outcome measure. (i) Women with dyspareunia exhibited more mate guarding and duty/pressure motives for intercourse and were less sexually autonomous than controls. (ii) Symptomatic women had more maladaptive penetration-related beliefs than controls, with women with vaginismus reporting the strongest maladaptive beliefs. (iii) Partners of women with dyspareunia self-reported more negative responses to pain than those of women with vaginismus. (iv) The factors that best predicted sexual pain behavior were the partner responses to pain and the woman's maladaptive beliefs regarding vaginal penetration. Our findings reveal support for task persistence in women with dyspareunia and fear avoidance in women with lifelong vaginismus. As such, it is important to consider these distinct types of responding to sexual pain when treating SPD. © 2014 International

Altering attentional control settings causes persistent biases of visual attention.

Science.gov (United States)

Knight, Helen C; Smith, Daniel T; Knight, David C; Ellison, Amanda

2016-01-01

Attentional control settings have an important role in guiding visual behaviour. Previous work within cognitive psychology has found that the deployment of general attentional control settings can be modulated by training. However, research has not yet established whether long-term modifications of one particular type of attentional control setting can be induced. To address this, we investigated persistent alterations to feature search mode, also known as an attentional bias, towards an arbitrary stimulus in healthy participants. Subjects were biased towards the colour green by an information sheet. Attentional bias was assessed using a change detection task. After an interval of either 1 or 2 weeks, participants were then retested on the same change detection task, tested on a different change detection task where colour was irrelevant, or were biased towards an alternative colour. One experiment included trials in which the distractor stimuli (but never the target stimuli) were green. The key finding was that green stimuli in the second task attracted attention, despite this impairing task performance. Furthermore, inducing a second attentional bias did not override the initial bias toward green objects. The attentional bias also persisted for at least two weeks. It is argued that this persistent attentional bias is mediated by a chronic change to participants' attentional control settings, which is aided by long-term representations involving contextual cueing. We speculate that similar changes to attentional control settings and continuous cueing may relate to attentional biases observed in psychopathologies. Targeting these biases may be a productive approach to treatment.

Task Demands in OSCEs Influence Learning Strategies.

Science.gov (United States)

Lafleur, Alexandre; Laflamme, Jonathan; Leppink, Jimmie; Côté, Luc

2017-01-01

Models on pre-assessment learning effects confirmed that task demands stand out among the factors assessors can modify in an assessment to influence learning. However, little is known about which tasks in objective structured clinical examinations (OSCEs) improve students' cognitive and metacognitive processes. Research is needed to support OSCE designs that benefit students' metacognitive strategies when they are studying, reinforcing a hypothesis-driven approach. With that intent, hypothesis-driven physical examination (HDPE) assessments ask students to elicit and interpret findings of the physical exam to reach a diagnosis ("Examine this patient with a painful shoulder to reach a diagnosis"). When studying for HDPE, students will dedicate more time to hypothesis-driven discussions and practice than when studying for a part-task OSCE ("Perform the shoulder exam"). It is expected that the whole-task nature of HDPE will lead to a hypothesis-oriented use of the learning resources, a frequent use of adjustment strategies, and persistence with learning. In a mixed-methods study, 40 medical students were randomly paired and filmed while studying together for two hypothetical OSCE stations. Each 25-min study period began with video cues asking to study for either a part-task OSCE or an HDPE. In a crossover design, sequences were randomized for OSCEs and contents (shoulder or spine). Time-on-task for discussions or practice were categorized as "hypothesis-driven" or "sequence of signs and maneuvers." Content analysis of focus group interviews summarized students' perception of learning resources, adjustment strategies, and persistence with learning. When studying for HDPE, students allocate significantly more time for hypothesis-driven discussions and practice. Students use resources contrasting diagnoses and report persistence with learning. When studying for part-task OSCEs, time-on-task is reversed, spent on rehearsing a sequence of signs and maneuvers. OSCEs with

Information seeking research needs extension towards tasks and technology

Directory of Open Access Journals (Sweden)

Kalervo Järvelin

2004-01-01

Full Text Available This paper discusses the research into information seeking and its directions at a general level. We approach this topic by analysis and argumentation based on past research in the domain. We begin by presenting a general model of information seeking and retrieval (IS&R which is used to derive nine broad dimensions that are needed to analyze IS&R. Past research is then contrasted with the dimensions and shown not to cover the dimensions sufficiently. Based on an analysis of the goals of information seeking research, and a view on human task performance augmentation, it is then shown that information seeking is intimately associated with, and dependent on, other aspects of work; tasks and technology included. This leads to a discussion on design and evaluation frameworks for IS&R, based on which two action lines are proposed: information retrieval research needs extension towards more context and information seeking research needs extension towards tasks and technology.

Mood-congruent false memories persist over time

OpenAIRE

Knott, L.; Thorley, C.

2014-01-01

In this study we examined the role of mood-congruency and retention interval on the false recognition of emotion laden items using the Deese/Roediger-McDermott (DRM) paradigm. Previous research has shown a mood-congruent false memory enhancement during immediate recognition tasks. The present study examined the persistence of this effect following a one-week delay. Participants were placed in a negative or neutral mood, presented with negative-emotion and neutral-emotion DRM word lists, and a...

Over the hill at 24: persistent age-related cognitive-motor decline in reaction times in an ecologically valid video game task begins in early adulthood.

Directory of Open Access Journals (Sweden)

Joseph J Thompson

Full Text Available Typically studies of the effects of aging on cognitive-motor performance emphasize changes in elderly populations. Although some research is directly concerned with when age-related decline actually begins, studies are often based on relatively simple reaction time tasks, making it impossible to gauge the impact of experience in compensating for this decline in a real world task. The present study investigates age-related changes in cognitive motor performance through adolescence and adulthood in a complex real world task, the real-time strategy video game StarCraft 2. In this paper we analyze the influence of age on performance using a dataset of 3,305 players, aged 16-44, collected by Thompson, Blair, Chen & Henrey [1]. Using a piecewise regression analysis, we find that age-related slowing of within-game, self-initiated response times begins at 24 years of age. We find no evidence for the common belief expertise should attenuate domain-specific cognitive decline. Domain-specific response time declines appear to persist regardless of skill level. A second analysis of dual-task performance finds no evidence of a corresponding age-related decline. Finally, an exploratory analyses of other age-related differences suggests that older participants may have been compensating for a loss in response speed through the use of game mechanics that reduce cognitive load.

Over the hill at 24: persistent age-related cognitive-motor decline in reaction times in an ecologically valid video game task begins in early adulthood.

Science.gov (United States)

Thompson, Joseph J; Blair, Mark R; Henrey, Andrew J

2014-01-01

Typically studies of the effects of aging on cognitive-motor performance emphasize changes in elderly populations. Although some research is directly concerned with when age-related decline actually begins, studies are often based on relatively simple reaction time tasks, making it impossible to gauge the impact of experience in compensating for this decline in a real world task. The present study investigates age-related changes in cognitive motor performance through adolescence and adulthood in a complex real world task, the real-time strategy video game StarCraft 2. In this paper we analyze the influence of age on performance using a dataset of 3,305 players, aged 16-44, collected by Thompson, Blair, Chen & Henrey [1]. Using a piecewise regression analysis, we find that age-related slowing of within-game, self-initiated response times begins at 24 years of age. We find no evidence for the common belief expertise should attenuate domain-specific cognitive decline. Domain-specific response time declines appear to persist regardless of skill level. A second analysis of dual-task performance finds no evidence of a corresponding age-related decline. Finally, an exploratory analyses of other age-related differences suggests that older participants may have been compensating for a loss in response speed through the use of game mechanics that reduce cognitive load.

Persistence and resistance to extinction in the domestic dog: Basic research and applications to canine training.

Science.gov (United States)

Hall, Nathaniel J

2017-08-01

This review summarizes the research investigating behavioral persistence and resistance to extinction in the dog. The first part of this paper reviews Behavioral Momentum Theory and its applications to Applied Behavior Analysis and training of pet dogs with persistent behavioral problems. I also highlight how research on Behavioral Momentum Theory can be applied to the training of detection dogs in an attempt to enhance detection performance in the presence of behavioral disruptors common in operational settings. In the second part of this review, I highlight more basic research on behavioral persistence with dogs, and how breed differences and experiences with humans as alternative sources of reinforcement can influence dogs' resistance to extinction of a target behavior. Applied Behavior Analysis and Behavior Momentum Theory have important applications for behavioral treatments to reduce the persistence of problem behavior in dogs and for the development of enhanced training methods that enhance the persistence of working dogs. Dogs can also be leveraged as natural models of stereotypic behavior and for exploring individual differences in behavioral persistence by evaluating breed and environmental variables associated with differences in canine persistance. Copyright © 2017 Elsevier B.V. All rights reserved.

Cognitive structure, flexibility, and plasticity in human multitasking-An integrative review of dual-task and task-switching research.

Science.gov (United States)

Koch, Iring; Poljac, Edita; Müller, Hermann; Kiesel, Andrea

2018-06-01

Numerous studies showed decreased performance in situations that require multiple tasks or actions relative to appropriate control conditions. Because humans often engage in such multitasking activities, it is important to understand how multitasking affects performance. In the present article, we argue that research on dual-task interference and sequential task switching has proceeded largely separately using different experimental paradigms and methodology. In our article we aim at organizing this complex set of research in terms of three complementary research perspectives on human multitasking. One perspective refers to structural accounts in terms of cognitive bottlenecks (i.e., critical processing stages). A second perspective refers to cognitive flexibility in terms of the underlying cognitive control processes. A third perspective emphasizes cognitive plasticity in terms of the influence of practice on human multitasking abilities. With our review article we aimed at highlighting the value of an integrative position that goes beyond isolated consideration of a single theoretical research perspective and that broadens the focus from single experimental paradigms (dual task and task switching) to favor instead a view that emphasizes the fundamental similarity of the underlying cognitive mechanisms across multitasking paradigms. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

National soft science research task item-organization and implementation

International Nuclear Information System (INIS)

Zhang Yiming

2014-01-01

International Thermonuclear Experimental Reactor (ITER) project, as the most large-scale science project and research cooperation plan in the human history, has brought together major world-wide scientific and technological achievements in current controlled magnetic confinement fusion research. The project is aiming at validating the scientific and technological feasibility of the peaceful use of fusion energy, laying a science and technology foundation for the realization of the fusion energy commercialization. Promoted by the ITER project, the nuclear fusion frontier science researches and experiments in China have made a deep development, and have made remarkable achievements. Based on this situation, the Fusion Information Division of the Southwestern Institute of Physics (SWIP) has undertaken the soft science research task item -Prediction of Nuclear Fusion Energy Research and Development Technology in China,issued by the Ministry of Science and Technology of China. The research team has gone through these processes such as documentation collection and investigation, documentation reading and refining, outline determination, the first draft writing, content analysis and optimization for the draft, and the internal trial within the research team, review and revise from the experts at SWIP and out of SWIP, evaluation from China International Nuclear Fusion Energy Program Execution Center (ITER China DA), as well as evaluation from the famous experts in domestic fusion community by means of letters and mail. Finally, the research team has completed the research report successfully. In this report, the fusion development strategies of the world's leading fusion research countries and organizations participating in ITER project have been described. Moreover, some comparisons and analysis in this report have been made in order to provide scientific and technological research, analysis base, as well as strategic decision references for exploring medium and long term

Persistence of Value-Driven Attentional Capture

Science.gov (United States)

Anderson, Brian A.; Yantis, Steven

2013-01-01

Stimuli that have previously been associated with the delivery of reward involuntarily capture attention when presented as unrewarded and task-irrelevant distractors in a subsequent visual search task. It is unknown how long such effects of reward learning on attention persist. One possibility is that value-driven attentional biases are plastic…

Future Tasks of the International Calvin Research

Directory of Open Access Journals (Sweden)

W. H. Neuser

1998-12-01

The first answer includes both a review of the previous six Congresses as well as a glance at recent Calvin literature; the second answer will be developed in the overview which follows, titled The future tasks of Calvin research.

Persistent Discontinuities in Global Software Development Teams: Adaption through Closely Coupled Work Practices

DEFF Research Database (Denmark)

Jensen, Rasmus Eskild

this as a starting point, it is clear that researchers still know little about how practitioners adjust and adapt to persistent discontinuities in globally distributed teams or how practitioners coordinate the work to bridge persistent discontinuities. Investigating the data material from an ethnographic work place...... and personal connections on several levels. These connections made the team more resistant to frequent changes in the team composition and made it easier to trace commitment in the everyday work, which was essential for completing the task. In conclusion, the dissertation found that changes...

Decision-making in research tasks with sequential testing.

Directory of Open Access Journals (Sweden)

Thomas Pfeiffer

Full Text Available BACKGROUND: In a recent controversial essay, published by JPA Ioannidis in PLoS Medicine, it has been argued that in some research fields, most of the published findings are false. Based on theoretical reasoning it can be shown that small effect sizes, error-prone tests, low priors of the tested hypotheses and biases in the evaluation and publication of research findings increase the fraction of false positives. These findings raise concerns about the reliability of research. However, they are based on a very simple scenario of scientific research, where single tests are used to evaluate independent hypotheses. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we present computer simulations and experimental approaches for analyzing more realistic scenarios. In these scenarios, research tasks are solved sequentially, i.e. subsequent tests can be chosen depending on previous results. We investigate simple sequential testing and scenarios where only a selected subset of results can be published and used for future rounds of test choice. Results from computer simulations indicate that for the tasks analyzed in this study, the fraction of false among the positive findings declines over several rounds of testing if the most informative tests are performed. Our experiments show that human subjects frequently perform the most informative tests, leading to a decline of false positives as expected from the simulations. CONCLUSIONS/SIGNIFICANCE: For the research tasks studied here, findings tend to become more reliable over time. We also find that the performance in those experimental settings where not all performed tests could be published turned out to be surprisingly inefficient. Our results may help optimize existing procedures used in the practice of scientific research and provide guidance for the development of novel forms of scholarly communication.

TxDOT administration research : tasks completed in FY2009.

Science.gov (United States)

2010-01-01

Texas Department of Transportation (TxDOT) Project 0-6581-TI, TxDOT Administration : Research, encompasses multiple tasks that explore and support administrative aspects of : transportation research. : The project term began in October 2008 and has b...

Expectancy-Value Theory in Persistence of Learning Effects in Schizophrenia: Role of Task Value and Perceived Competency

OpenAIRE

Choi, Jimmy; Fiszdon, Joanna M.; Medalia, Alice

2010-01-01

Expectancy-value theory, a widely accepted model of motivation, posits that expectations of success on a learning task and the individual value placed on the task are central determinants of motivation to learn. This is supported by research in healthy controls suggesting that beliefs of self-and-content mastery can be so influential they can predict the degree of improvement on challenging cognitive tasks even more so than general cognitive ability. We examined components of expectancy-value...

Task-Based Language Learning and Teaching: An Action-Research Study

Science.gov (United States)

Calvert, Megan; Sheen, Younghee

2015-01-01

The creation, implementation, and evaluation of language learning tasks remain a challenge for many teachers, especially those with limited experience with using tasks in their teaching. This action-research study reports on one teacher's experience of developing, implementing, critically reflecting on, and modifying a language learning task…

Neural processes underlying cultural differences in cognitive persistence.

Science.gov (United States)

Telzer, Eva H; Qu, Yang; Lin, Lynda C

2017-08-01

Self-improvement motivation, which occurs when individuals seek to improve upon their competence by gaining new knowledge and improving upon their skills, is critical for cognitive, social, and educational adjustment. While many studies have delineated the neural mechanisms supporting extrinsic motivation induced by monetary rewards, less work has examined the neural processes that support intrinsically motivated behaviors, such as self-improvement motivation. Because cultural groups traditionally vary in terms of their self-improvement motivation, we examined cultural differences in the behavioral and neural processes underlying motivated behaviors during cognitive persistence in the absence of extrinsic rewards. In Study 1, 71 American (47 females, M=19.68 years) and 68 Chinese (38 females, M=19.37 years) students completed a behavioral cognitive control task that required cognitive persistence across time. In Study 2, 14 American and 15 Chinese students completed the same cognitive persistence task during an fMRI scan. Across both studies, American students showed significant declines in cognitive performance across time, whereas Chinese participants demonstrated effective cognitive persistence. These behavioral effects were explained by cultural differences in self-improvement motivation and paralleled by increasing activation and functional coupling between the inferior frontal gyrus (IFG) and ventral striatum (VS) across the task among Chinese participants, neural activation and coupling that remained low in American participants. These findings suggest a potential neural mechanism by which the VS and IFG work in concert to promote cognitive persistence in the absence of extrinsic rewards. Thus, frontostriatal circuitry may be a neurobiological signal representing intrinsic motivation for self-improvement that serves an adaptive function, increasing Chinese students' motivation to engage in cognitive persistence. Copyright © 2017 Elsevier Inc. All rights

Persistent Identifiers for Field Expeditions: A Next Step for the US Oceanographic Research Fleet

Science.gov (United States)

Arko, Robert; Carbotte, Suzanne; Chandler, Cynthia; Smith, Shawn; Stocks, Karen

2016-04-01

Oceanographic research cruises are complex affairs, typically requiring an extensive effort to secure the funding, plan the experiment, and mobilize the field party. Yet cruises are not typically published online as first-class digital objects with persistent, citable identifiers linked to the scientific literature. The Rolling Deck to Repository (R2R; info@rvdata.us) program maintains a master catalog of oceanographic cruises for the United States research fleet, currently documenting over 6,000 expeditions on 37 active and retired vessels. In 2015, R2R started routinely publishing a Digital Object Identifier (DOI) for each completed cruise. Cruise DOIs, in turn, are linked to related persistent identifiers where available including the Open Researcher and Contributor ID (ORCID) for members of the science party, the International Geo Sample Number (IGSN) for physical specimens collected during the cruise, the Open Funder Registry (FundRef) codes that supported the experiment, and additional DOIs for datasets, journal articles, and other products resulting from the cruise. Publishing a persistent identifier for each field expedition will facilitate interoperability between the many different repositories that hold research products from cruises; will provide credit to the investigators who secured the funding and carried out the experiment; and will facilitate the gathering of fleet-wide altmetrics that demonstrate the broad impact of oceanographic research.

Implicit Behavioral Change in Response to Cognitive Tasks in Alzheimer Disease.

Science.gov (United States)

Bomilcar, Iris; Morris, Robin G; Brown, Richard G; Mograbi, Daniel C

2018-03-01

Lack of awareness about impairments is commonly found in Alzheimer disease (AD), but recent evidence suggests that patients may respond to the experience of illness despite limited awareness. In this study, we explored whether implicit emotional responses to experiences of failure in cognitive tasks would result in longer-term change in behavior. Twenty-two patients with AD were seen 1 week after a previous session in which they performed computer tasks that had been manipulated to be either too difficult (failure condition) or very easy (success condition) for them. At the second session, both types of tasks were set to have medium difficulty and were administered so that the participants decided how long to persist on each task. Task persistence was determined by relative time spent doing the tasks, considering that participants would be more likely to stop performing tasks in which they had experienced failure during the first session. Task persistence in the second session was not affected by performance in the first session. However, when participants' awareness of performance in the first session was taken into account, differences were found in persistence between tasks in the second session. During the second session, participants stopped performing tasks after a sequence of errors. There were no self-reported changes in motivation or enjoyment in response to task failure. These findings suggest that implicit learning of task valence may be compromised in AD, but that initial moments of awareness of performance may influence long-term adaptation in unaware patients.

Collaborative Research and Development (CR&D). Task Order 0049: Tribological Modeling

Science.gov (United States)

2008-05-01

scratch test for TiN on stainless steel with better substrate mechanical properties. This present study was focused on the study of stress distribution...AFRL-RX-WP-TR-2010-4189 COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling Young Sup Kang Universal...SUBTITLE COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling 5a. CONTRACT NUMBER F33615-03-D-5801-0049 5b

Heuristic Task Analysis on E-Learning Course Development: A Formative Research Study

Science.gov (United States)

Lee, Ji-Yeon; Reigeluth, Charles M.

2009-01-01

Utilizing heuristic task analysis (HTA), a method developed for eliciting, analyzing, and representing expertise in complex cognitive tasks, a formative research study was conducted on the task of e-learning course development to further improve the HTA process. Three instructional designers from three different post-secondary institutions in the…

Scientific Merit Review of Directed Research Tasks Within the NASA Human Research Program

Science.gov (United States)

Charles, John B.

2010-01-01

The Human Research Program is instrumental in developing and delivering research findings, health countermeasures, and human systems technologies for spacecraft. :HRP is subdivided into 6 research entities, or Elements. Each Element is charged with providing the Program with knowledge and capabilities to conduct research to address the human health and performance risks as well as advance the readiness levels of technology and countermeasures. Project: An Element may be further subdivided into Projects, which are defined as an integrated set of tasks undertaken to deliver a product or set of products

Academic Users' Information Searching on Research Topics: Characteristics of Research Tasks and Search Strategies

Science.gov (United States)

Du, Jia Tina; Evans, Nina

2011-01-01

This project investigated how academic users search for information on their real-life research tasks. This article presents the findings of the first of two studies. The study data were collected in the Queensland University of Technology (QUT) in Brisbane, Australia. Eleven PhD students' searching behaviors on personal research topics were…

Game-like tasks for comparative research: leveling the playing field

Science.gov (United States)

Washburn, D. A.; Gulledge, J. P.; Rumbaugh, D. M. (Principal Investigator)

1995-01-01

Game-like computer tasks offer many benefits for psychological research. In this paper, the usefulness of such tasks to bridge population differences (e.g., age, intelligence, species) is discussed and illustrated. A task called ALVIN was used to assess humans' and monkeys' working memory for sequences of colors with or without tones. Humans repeated longer lists than did the monkeys, and only humans benefited when the visual stimuli were accompanied by auditory cues. However, the monkeys did recall sequences at levels comparable to those reported elsewhere for children. Comparison of similarities and differences between the species is possible because the two groups were tested with exactly the same game-like paradigm.

Maternal support for autonomy: relationships with persistence for children with Down syndrome and typically developing children.

Science.gov (United States)

Gilmore, Linda; Cuskelly, Monica; Jobling, Anne; Hayes, Alan

2009-01-01

Maternal behaviors and child mastery behaviors were examined in 25 children with Down syndrome and 43 typically developing children matched for mental age (24-36 months). During a shared problem-solving task, there were no group differences in maternal directiveness or support for autonomy, and mothers in the two groups used similar verbal strategies when helping their child. There were also no group differences in child mastery behaviors, measured as persistence with two optimally challenging tasks. However, the two groups differed in the relationships of maternal style with child persistence. Children with Down syndrome whose mothers were more supportive of their autonomy in the shared task displayed greater persistence when working independently on a challenging puzzle, while children of highly directive mothers displayed lower levels of persistence. For typically developing children, persistence was unrelated to maternal style, suggesting that mother behaviors may have different causes or consequences in the two groups.

Succumbing to Bottom-Up Biases on Task Choice Predicts Increased Switch Costs in the Voluntary Task Switching Paradigm

Science.gov (United States)

Orr, Joseph M.; Weissman, Daniel H.

2010-01-01

Bottom-up biases are widely thought to influence task choice in the voluntary task switching paradigm. Definitive support for this hypothesis is lacking, however, because task choice and task performance are usually confounded. We therefore revisited this hypothesis using a paradigm in which task choice and task performance are temporally separated. As predicted, participants tended to choose the task that was primed by bottom-up biases. Moreover, such choices were linked to increased switch costs during subsequent task performance. These findings provide compelling evidence that bottom-up biases influence voluntary task choice. They also suggest that succumbing to such biases reflects a reduction of top-down control that persists to influence upcoming task performance. PMID:21713192

Complexity, Accuracy, Fluency and Lexis in Task-Based Performance: A Synthesis of the Ealing Research

Science.gov (United States)

Skehan, Peter; Foster, Pauline

2012-01-01

This chapter will present a research synthesis of a series of studies, termed here the Ealing research. The studies use the same general framework to conceptualise tasks and task performance, enabling easier comparability. The different studies, although each is self-contained, build into a wider picture of task performance. The major point of…

The modality effect and echoic persistence.

Science.gov (United States)

Watkins, O C; Watkins, M J

1980-09-01

The modality effect refers to the higher level of recall of the last few items of a list when presentation is auditory as opposed to visual. It is usually attributed to echoic memory. The effect may be sharply reduced by an ostensibly irrelevant auditory item appended to the end of the list. Previous research suggests that this "suffix effect" arises only when the suffix item occurs within 2 sec of the last list item. This finding strengthens the widely held assumption that echoic information decays within 2 sec, and has led to the assumption that if echoic information is to be useful in serial recall it must first be encoded into a more durable modality-independent form. Both assumptions conflict with the research reported here. The first two experiments demonstrate substantial suffix effects with suffix delays of 2 and 4 sec, indicating that echoic information lasts at least 4 sec. This finding implies that echoic information may aid recall directly, an implication that was supported in Experiments 3 and 4. In Experiment 3 serial recall was interrupted with a brief distractor task. The modality effect was smaller when this task was auditory than when it was visual, suggesting that echoic information was still available immediately prior to recency recall. In Experiment 4 list presentation was broken by a 4-sec pause; the modalities of the list halves were combined factorially. Interest focused on the recency positions of the first half. A modality effect was found at these positions when the second half was visual but not when it was auditory. This is contrary to the hypothesis that echoic information is encoded before recall, but is consistent with the hypothesis that echoic information is encoded before recall, but is consistent with the alternative hypothesis that echoic information is used directly at recall. The final two experiments concern the modality effect found when a delay is interpolated between list presentation and recall. Experiment 5 showed that

Working memory representations persist in the face of unexpected task alterations.

Science.gov (United States)

Swan, Garrett; Wyble, Brad; Chen, Hui

2017-07-01

It is well known that information can be held in memory while performing other tasks concurrently, such as remembering a color or number during a separate visual search task. However, it is not clear what happens to stored information in the face of unexpected tasks, such as the surprise questions that are often used in experiments related to inattentional and change blindness. Does the unpredicted shift in task context cause memory representations to be cleared in anticipation of new information? To answer this question, we ran two experiments where the task unexpectedly switched partway through the experiment with a surprise question. Half of the participants were asked to report the same attribute (Exp. 1 = Identity, Exp. 2 = Color) of a target stimulus in both presurprise and postsurprise trials, while for the other half, the reported attribute switched from identity to color (Exp. 1) or vice versa (Exp. 2). Importantly, all participants had to read an unexpected set of instructions and respond differently on the surprise trial. Accuracy on the surprise trial was higher for the same-attribute groups than the different-attribute groups. Furthermore, there was no difference in reaction time on the surprise trial between the two groups. These results suggest that information participants expected to report can survive an encounter with an unexpected task. The implication is that failures to report information on a surprise trial in many experiments reflect genuine differences in memory encoding, rather than forgetting or overwriting induced by the surprise question.

Research Priorities in Limb and Task-Specific Dystonias

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Pirio Richardson, Sarah; Altenmüller, Eckart; Alter, Katharine; Alterman, Ron L.; Chen, Robert; Frucht, Steven; Furuya, Shinichi; Jankovic, Joseph; Jinnah, H. A.; Kimberley, Teresa J.; Lungu, Codrin; Perlmutter, Joel S.; Prudente, Cecília N.; Hallett, Mark

2017-01-01

Dystonia, which causes intermittent or sustained abnormal postures and movements, can present in a focal or a generalized manner. In the limbs, focal dystonia can occur in either the upper or lower limbs and may be task-specific causing abnormal motor performance for only a specific task, such as in writer’s cramp, runner’s dystonia, or musician’s dystonia. Focal limb dystonia can be non-task-specific and may, in some circumstances, be associated with parkinsonian disorders. The true prevalence of focal limb dystonia is not known and is likely currently underestimated, leaving a knowledge gap and an opportunity for future research. The pathophysiology of focal limb dystonia shares some commonalities with other dystonias with a loss of inhibition in the central nervous system and a loss of the normal regulation of plasticity, called homeostatic plasticity. Functional imaging studies revealed abnormalities in several anatomical networks that involve the cortex, basal ganglia, and cerebellum. Further studies should focus on distinguishing cause from effect in both physiology and imaging studies to permit focus on most relevant biological correlates of dystonia. There is no specific therapy for the treatment of limb dystonia given the variability in presentation, but off-label botulinum toxin therapy is often applied to focal limb and task-specific dystonia. Various rehabilitation techniques have been applied and rehabilitation interventions may improve outcomes, but small sample size and lack of direct comparisons between methods to evaluate comparative efficacy limit conclusions. Finally, non-invasive and invasive therapeutic modalities have been explored in small studies with design limitations that do not yet clearly provide direction for larger clinical trials that could support new clinical therapies. Given these gaps in our clinical, pathophysiologic, and therapeutic knowledge, we have identified priorities for future research including: the development of

Research Priorities in Limb and Task-Specific Dystonias

Directory of Open Access Journals (Sweden)

Sarah Pirio Richardson

2017-05-01

Full Text Available Dystonia, which causes intermittent or sustained abnormal postures and movements, can present in a focal or a generalized manner. In the limbs, focal dystonia can occur in either the upper or lower limbs and may be task-specific causing abnormal motor performance for only a specific task, such as in writer’s cramp, runner’s dystonia, or musician’s dystonia. Focal limb dystonia can be non-task-specific and may, in some circumstances, be associated with parkinsonian disorders. The true prevalence of focal limb dystonia is not known and is likely currently underestimated, leaving a knowledge gap and an opportunity for future research. The pathophysiology of focal limb dystonia shares some commonalities with other dystonias with a loss of inhibition in the central nervous system and a loss of the normal regulation of plasticity, called homeostatic plasticity. Functional imaging studies revealed abnormalities in several anatomical networks that involve the cortex, basal ganglia, and cerebellum. Further studies should focus on distinguishing cause from effect in both physiology and imaging studies to permit focus on most relevant biological correlates of dystonia. There is no specific therapy for the treatment of limb dystonia given the variability in presentation, but off-label botulinum toxin therapy is often applied to focal limb and task-specific dystonia. Various rehabilitation techniques have been applied and rehabilitation interventions may improve outcomes, but small sample size and lack of direct comparisons between methods to evaluate comparative efficacy limit conclusions. Finally, non-invasive and invasive therapeutic modalities have been explored in small studies with design limitations that do not yet clearly provide direction for larger clinical trials that could support new clinical therapies. Given these gaps in our clinical, pathophysiologic, and therapeutic knowledge, we have identified priorities for future research including

What is a missing link among wireless persistent surveillance?

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Hsu, Charles; Szu, Harold

2011-06-01

The next generation surveillance system will equip with versatile sensor devices and information focus capable of conducting regular and irregular surveillance and security environments worldwide. The community of the persistent surveillance must invest the limited energy and money effectively into researching enabling technologies such as nanotechnology, wireless networks, and micro-electromechanical systems (MEMS) to develop persistent surveillance applications for the future. Wireless sensor networks can be used by the military for a number of purposes such as monitoring militant activity in remote areas and force protection. Being equipped with appropriate sensors these networks can enable detection of enemy movement, identification of enemy force and analysis of their movement and progress. Among these sensor network technologies, covert communication is one of the challenging tasks in the persistent surveillance because it is highly demanded to provide secured sensor nodes and linkage for fear of deliberate sabotage. Due to the matured VLSI/DSP technologies, affordable COTS of UWB technology with noise-like direct sequence (DS) time-domain pulses is a potential solution to support low probability of intercept and low probability of detection (LPI/LPD) data communication and transmission. This paper will describe a number of technical challenges in wireless persistent surveillance development include covert communication, network control and routing, collaborating signal and information processing, and etc. The paper concludes by presenting Hermitian Wavelets to enhance SNR in support of secured communication.

Practice makes perfect: familiarity of task determines success in solvable tasks for free-ranging dogs (Canis lupus familiaris).

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Bhattacharjee, Debottam; Dasgupta, Sandipan; Biswas, Arpita; Deheria, Jayshree; Gupta, Shreya; Nikhil Dev, N; Udell, Monique; Bhadra, Anindita

2017-07-01

Domestic dogs' (Canis lupus familiaris) socio-cognitive faculties have made them highly sensitive to human social cues. While dogs often excel at understanding human communicative gestures, they perform comparatively poorly in problem-solving and physical reasoning tasks. This difference in their behaviour could be due to the lifestyle and intense socialization, where problem solving and physical cognition are less important than social cognition. Free-ranging dogs live in human-dominated environments, not under human supervision and are less socialized. Being scavengers, they often encounter challenges where problem solving is required in order to get access to food. We tested Indian street dogs in familiar and unfamiliar independent solvable tasks and quantified their persistence and dependence on a novel human experimenter, in addition to their success in solving a task. Our results indicate that free-ranging dogs succeeded and persisted more in the familiar task as compared to the unfamiliar one. They showed negligible amount of human dependence in the familiar task, but showed prolonged gazing and considerable begging behaviour to the human experimenter in the context of the unfamiliar task. Cognitive abilities of free-ranging dogs thus play a pivotal role in determining task-associated behaviours based on familiarity. In addition to that, these dogs inherently tend to socialize with and depend on humans, even if they are strangers. Our results also illustrate free-ranging dogs' low competence at physical cognitive tasks.

Regular Exercise Enhances Task-Based Industriousness in Laboratory Rats.

Directory of Open Access Journals (Sweden)

Nicholas C Laurence

Full Text Available Individuals vary greatly in their willingness to select and persist in effortful tasks, even when high-effort will knowingly result in high-reward. Individuals who select and successively complete effortful, goal-directed tasks can be described as industrious. Trying to increase one's industriousness is desirable from a productivity standpoint, yet intrinsically challenging given that effort expenditure is generally aversive. Here we show that in laboratory rats, a basic physical exercise regimen (20 min/day, five days/week is sufficient to increase industriousness across a battery of subsequent testing tasks. Exercised rats outperformed their non-exercised counterparts in tasks designed to tax effort expenditure, strategic decision-making, problem solving and persistence. These increases in performance led to quicker reward obtainment and greater reward gain over time, and could not be accounted for simply by increased locomotor activity. Our results suggest that a basic exercise regimen can enhance effortful goal-directed behaviour in goal-directed tasks, which highlights a potential productivity benefit of staying physically active.

MOOCs and Persistence: Definitions and Predictors

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Evans, Brent J.; Baker, Rachel B.

2016-01-01

The chapter argues for redefining the term "persistence" as it relates to MOOCs and considers how different measures produce different results in the research; it closes with a review of research on persistence in MOOCs.

Cognitive implications of facilitating echoic persistence.

Science.gov (United States)

Baldwin, Carryl L

2007-06-01

Seventeen participants performed a tone-pattern-matching task at different presentation levels while concurrently engaged in a simulated-driving task. Presentation levels of 60, 65, and 70 dBC (SPL) were combined factorially with tone-matching delays of 2, 3, and 4 sec. Intensity had no effect on performance in single-task conditions and short-delay conditions. However, when the participants were engaged concurrently in the driving task, a significant interaction between presentation level and delay was observed. In the longest delay condition, the participants performed the tone-pattern-matching task more efficiently (more quickly and without additional errors) as presentation intensity increased. These findings demonstrate the interaction between sensory and cognitive processes and point to a direct-intensity relationship where intensity affects the persistence of echoic memory. Implications for facilitating auditory processing and improving auditory interfaces in complex systems (i.e., transportation environments), particularly for older and hearing-impaired listeners, are discussed.

Object Persistence Enhances Spatial Navigation: A Case Study in Smartphone Vision Science.

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Liverence, Brandon M; Scholl, Brian J

2015-07-01

Violations of spatiotemporal continuity disrupt performance in many tasks involving attention and working memory, but experiments on this topic have been limited to the study of moment-by-moment on-line perception, typically assessed by passive monitoring tasks. We tested whether persisting object representations also serve as underlying units of longer-term memory and active spatial navigation, using a novel paradigm inspired by the visual interfaces common to many smartphones. Participants used key presses to navigate through simple visual environments consisting of grids of icons (depicting real-world objects), only one of which was visible at a time through a static virtual window. Participants found target icons faster when navigation involved persistence cues (via sliding animations) than when persistence was disrupted (e.g., via temporally matched fading animations), with all transitions inspired by smartphone interfaces. Moreover, this difference occurred even after explicit memorization of the relevant information, which demonstrates that object persistence enhances spatial navigation in an automatic and irresistible fashion. © The Author(s) 2015.

Standardizing terminology and definitions of medication adherence and persistence in research employing electronic databases.

Science.gov (United States)

Raebel, Marsha A; Schmittdiel, Julie; Karter, Andrew J; Konieczny, Jennifer L; Steiner, John F

2013-08-01

To propose a unifying set of definitions for prescription adherence research utilizing electronic health record prescribing databases, prescription dispensing databases, and pharmacy claims databases and to provide a conceptual framework to operationalize these definitions consistently across studies. We reviewed recent literature to identify definitions in electronic database studies of prescription-filling patterns for chronic oral medications. We then develop a conceptual model and propose standardized terminology and definitions to describe prescription-filling behavior from electronic databases. The conceptual model we propose defines 2 separate constructs: medication adherence and persistence. We define primary and secondary adherence as distinct subtypes of adherence. Metrics for estimating secondary adherence are discussed and critiqued, including a newer metric (New Prescription Medication Gap measure) that enables estimation of both primary and secondary adherence. Terminology currently used in prescription adherence research employing electronic databases lacks consistency. We propose a clear, consistent, broadly applicable conceptual model and terminology for such studies. The model and definitions facilitate research utilizing electronic medication prescribing, dispensing, and/or claims databases and encompasses the entire continuum of prescription-filling behavior. Employing conceptually clear and consistent terminology to define medication adherence and persistence will facilitate future comparative effectiveness research and meta-analytic studies that utilize electronic prescription and dispensing records.

The Planning Task for Teams (PLATT): An environment for research on planning and decision making in teams

NARCIS (Netherlands)

Kamphuis, W.; Houttuin, K.

2007-01-01

In this report, we introduce a newly developed task environment for experimental team research: the Planning Task for Teams (PLATT). PLATT is a scenario based, computerized, complex planning task for three-person teams. PLATT has been designed to be able to do experimental laboratory research on

Seminar Cum Meeting Report: Codata Task Group for Exchangeable Material Data Representation to Support Research and Education

Directory of Open Access Journals (Sweden)

T Ashino

2008-11-01

Full Text Available On March 4-5, 2008, the CODATA Task Group for Exchangeable Material Data Representation to Support Research and Education held a two day seminar cum meeting at the National Physical Laboratory (NPL, New Delhi, India, with NPL materials researchers and task group members representing material activities and databases from seven countries: European Union (The Czech Republic, France, and the Netherlands, India, Korea, Japan, and the United States. The NPL seminar included presentations about the researchers' work. The Task Group meeting included presentations about current data related activities of the members. Joint discussions between NPL researchers and CODATA task group members began an exchange of viewpoints among materials data producers, users, and databases developers. The seminar cum meeting included plans to continue and expand Task Group activities at the 2008 CODATA 21st Meeting in Kyiv, Ukraine.

Main tasks of the Nuclear Research Institute in the period till the year 2000

International Nuclear Information System (INIS)

Podest, M.

1989-06-01

The main tasks of the Nuclear Research Institute will be oriented to: safety of nuclear power installations; expert and diagnostic systems for such installations; the effect of operating medium on the life of nuclear power plants; disposal of radioactive wastes; prospective nuclear sources; research into and development of radiopharmaceuticals; radiation technologies and methods. Specific tasks are itemized. The statute of the Institute is attached. (J.B.). 1 tab

Measuring treatment effects on dual-task performance: a framework for research and clinical practice

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Prudence ePlummer

2015-04-01

Full Text Available The relevance of dual-task walking to everyday ambulation is widely acknowledged, and numerous studies have demonstrated that dual-task interference can significantly impact recovery of functional walking in people with neurological disorders. The magnitude and direction of dual-task interference is influenced by the interaction between the two tasks, including how individuals spontaneously prioritize their attention. Therefore, to accurately interpret and characterize dual-task interference and identify changes over time, it is imperative to evaluate single and dual-task performance in both tasks, as well as the tasks relative to each other. Yet, reciprocal dual-task effects are frequently ignored. The purpose of this perspective paper is to present a framework for measuring treatment effects on dual-task interference, specifically taking into account the interactions between the two tasks and how this can provide information on whether overall dual-task capacity has improved or a different attentional strategy has been adopted. In discussing the clinical implications of using this framework, we provide specific examples of using this method and provide some explicit recommendations for research and clinical practice.

Infants make more attempts to achieve a goal when they see adults persist.

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Leonard, Julia A; Lee, Yuna; Schulz, Laura E

2017-09-22

Persistence, above and beyond IQ, is associated with long-term academic outcomes. To look at the effect of adult models on infants' persistence, we conducted an experiment in which 15-month-olds were assigned to one of three conditions: an Effort condition in which they saw an adult try repeatedly, using various methods, to achieve each of two different goals; a No Effort condition in which the adult achieved the goals effortlessly; or a Baseline condition. Infants were then given a difficult, novel task. Across an initial study and two preregistered experiments ( N = 262), infants in the Effort condition made more attempts to achieve the goal than did infants in the other conditions. Pedagogical cues modulated the effect. The results suggest that adult models causally affect infants' persistence and that infants can generalize the value of persistence to novel tasks. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Practice Makes Perfect: Correlations Between Prior Experience in High-level Athletics and Robotic Surgical Performance Do Not Persist After Task Repetition.

Science.gov (United States)

Shee, Kevin; Ghali, Fady M; Hyams, Elias S

Robotic surgical skill development is central to training in urology as well as in other surgical disciplines. Here, we describe a pilot study assessing the relationships between robotic surgery simulator performance and 3 categories of activities, namely, videogames, musical instruments, and athletics. A questionnaire was administered to preclinical medical students for general demographic information and prior experiences in surgery, videogames, musical instruments, and athletics. For follow-up performance studies, we used the Matchboard Level 1 and 2 modules on the da Vinci Skills Simulator, and recorded overall score, time to complete, economy of motion, workspace range, instrument collisions, instruments out of view, and drops. Task 1 was run once, whereas task 2 was run 3 times. All performance studies on the da Vinci Surgical Skills Simulator took place in the Simulation Center at Dartmouth-Hitchcock Medical Center. All participants were medical students at the Geisel School of Medicine. After excluding students with prior hands-on experience in surgery, a total of 30 students completed the study. We found a significant correlation between athletic skill level and performance for both task 1 (p = 0.0002) and task 2 (p = 0.0009). No significant correlations were found for videogame or musical instrument skill level. Students with experience in certain athletics (e.g., volleyball, tennis, and baseball) tended to perform better than students with experience in other athletics (e.g., track and field). For task 2, which was run 3 times, this association did not persist after the third repetition due to significant improvements in students with low-level athletic skill (levels 0-2). Our study suggests that prior experience in high-level athletics, but not videogames or musical instruments, significantly influences surgical proficiency in robot-naive students. Furthermore, our study suggests that practice through task repetition can overcome initial differences

Development of "Task Value" Instrument for Biology as a School Subject

Science.gov (United States)

Köksal, Mustafa Serdar; Yaman, Süleyman

2013-01-01

The expectancy-value model of motivation states that individuals' choice, persistence and performances are related to their beliefs about how much they value task. Despite the importance of "task value" in learning biology, lack of the instruments on task value for high school biology courses for practical use indicated requirement to…

Effects of noise and task loading on a communication task loading on a communication task

Science.gov (United States)

Orrell, Dean H., II

Previous research had shown the effect of noise on a single communication task. This research has been criticized as not being representative of a real world situation since subjects allocated all of their attention to only one task. In the present study, the effect of adding a loading task to a standard noise-communication paradigm was investigated. Subjects performed both a communication task (Modified Rhyme Test; House et al. 1965) and a short term memory task (Sternberg, 1969) in simulated levels of aircraft noise (95, 105 and 115 dB overall sound pressure level (OASPL)). Task loading was varied with Sternberg's task by requiring subjects to memorize one, four, or six alphanumeric characters. Simulated aircraft noise was varied between levels of 95, 105 and 115 dB OASPL using a pink noise source. Results show that the addition of Sternberg's task and little effect on the intelligibility of the communication task while response time for the communication task increased.

Persistent myalgia following whiplash.

Science.gov (United States)

Dommerholt, Jan

2005-10-01

Persistent myalgia following whiplash is commonly considered the result of poor psychosocial status, illness behavior, or failing coping skills. However, there is much evidence that persistent myalgia may be due to neurophysiologic mechanisms involving peripheral and central sensitization. Myofascial trigger points may play a crucial role in maintaining sensitization. Recent research suggests that the chemical environment of myofascial trigger points is an important factor. Several consequences are reviewed when central pain mechanisms and myofascial trigger points are included in the differential diagnosis and in the management of patients with persistent pain following whiplash.

Research on multirobot pursuit task allocation algorithm based on emotional cooperation factor.

Science.gov (United States)

Fang, Baofu; Chen, Lu; Wang, Hao; Dai, Shuanglu; Zhong, Qiubo

2014-01-01

Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots' individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.

Mood-congruent false memories persist over time.

Science.gov (United States)

Knott, Lauren M; Thorley, Craig

2014-01-01

In this study, we examined the role of mood-congruency and retention interval on the false recognition of emotion laden items using the Deese/Roediger-McDermott (DRM) paradigm. Previous research has shown a mood-congruent false memory enhancement during immediate recognition tasks. The present study examined the persistence of this effect following a one-week delay. Participants were placed in a negative or neutral mood, presented with negative-emotion and neutral-emotion DRM word lists, and administered with both immediate and delayed recognition tests. Results showed that a negative mood state increased remember judgments for negative-emotion critical lures, in comparison to neutral-emotion critical lures, on both immediate and delayed testing. These findings are discussed in relation to theories of spreading activation and emotion-enhanced memory, with consideration of the applied forensic implications of such findings.

The persistence of depression score

NARCIS (Netherlands)

Spijker, J.; de Graaf, R.; Ormel, J.; Nolen, W. A.; Grobbee, D. E.; Burger, H.

2006-01-01

Objective: To construct a score that allows prediction of major depressive episode (MDE) persistence in individuals with MDE using determinants of persistence identified in previous research. Method: Data were derived from 250 subjects from the general population with new MDE according to DSM-III-R.

Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

Science.gov (United States)

Gonzalez, María C.; Kramar, Cecilia P.; Tomaiuolo, Micol; Katche, Cynthia; Weisstaub, Noelia; Cammarota, Martín; Medina, Jorge H.

2014-01-01

Medial prefrontal cortex (mPFC) is essential for initial memory processing and expression but its involvement in persistent memory storage has seldom been studied. Using the hippocampus dependent inhibitory avoidance learning task and the hippocampus-independent conditioned taste aversion paradigm together with specific dopamine receptor agonists and antagonists we found that persistence but not formation of long-term aversive memories requires dopamine D1/D5 receptors activation in mPFC immediately after training and, depending on the task, between 6 and 12 h later. Our results indicate that besides its well-known participation in retrieval and early consolidation, mPFC also modulates the endurance of long-lasting aversive memories regardless of whether formation of the aversive mnemonic trace requires the participation of the hippocampus. PMID:25506318

Biomedical text mining for research rigor and integrity: tasks, challenges, directions.

Science.gov (United States)

Kilicoglu, Halil

2017-06-13

An estimated quarter of a trillion US dollars is invested in the biomedical research enterprise annually. There is growing alarm that a significant portion of this investment is wasted because of problems in reproducibility of research findings and in the rigor and integrity of research conduct and reporting. Recent years have seen a flurry of activities focusing on standardization and guideline development to enhance the reproducibility and rigor of biomedical research. Research activity is primarily communicated via textual artifacts, ranging from grant applications to journal publications. These artifacts can be both the source and the manifestation of practices leading to research waste. For example, an article may describe a poorly designed experiment, or the authors may reach conclusions not supported by the evidence presented. In this article, we pose the question of whether biomedical text mining techniques can assist the stakeholders in the biomedical research enterprise in doing their part toward enhancing research integrity and rigor. In particular, we identify four key areas in which text mining techniques can make a significant contribution: plagiarism/fraud detection, ensuring adherence to reporting guidelines, managing information overload and accurate citation/enhanced bibliometrics. We review the existing methods and tools for specific tasks, if they exist, or discuss relevant research that can provide guidance for future work. With the exponential increase in biomedical research output and the ability of text mining approaches to perform automatic tasks at large scale, we propose that such approaches can support tools that promote responsible research practices, providing significant benefits for the biomedical research enterprise. Published by Oxford University Press 2017. This work is written by a US Government employee and is in the public domain in the US.

The Technologist Function in Fields Related to Radiology: Tasks in Radiation Therapy and Diagnostic Ultrasound. Research Report No. 9; Relating Technologist Tasks in Diagnostic Radiology, Ultrasound and Radiation Therapy. Research Report No. 10.

Science.gov (United States)

Gilpatrick, Eleanor

The two research reports included in this document describe the application of the Health Services Mobility Study (HSMS) task analysis method to two technologist functions and examine the interrelationships of these tasks with those in diagnostic radiology. (The HSMS method includes processes for using the data for designing job ladders, for…

Research status of multi - robot systems task allocation and uncertainty treatment

Science.gov (United States)

Li, Dahui; Fan, Qi; Dai, Xuefeng

2017-08-01

The multi-robot coordination algorithm has become a hot research topic in the field of robotics in recent years. It has a wide range of applications and good application prospects. This paper analyzes and summarizes the current research status of multi-robot coordination algorithms at home and abroad. From task allocation and dealing with uncertainty, this paper discusses the multi-robot coordination algorithm and presents the advantages and disadvantages of each method commonly used.

Research on Multirobot Pursuit Task Allocation Algorithm Based on Emotional Cooperation Factor

Directory of Open Access Journals (Sweden)

Baofu Fang

2014-01-01

Full Text Available Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots’ individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.

The persistence of the subjective in neuropsychopharmacology: observations of contemporary hallucinogen research.

Science.gov (United States)

Langlitz, Nicolas

2010-01-01

The elimination of subjectivity through brain research and the replacement of so-called "folk psychology" by a neuroscientifically enlightened worldview and self-conception has been both hoped for and feared. But this cultural revolution is still pending. Based on nine months of fieldwork on the revival of hallucinogen research since the "Decade of the Brain," this paper examines how subjective experience appears as epistemic object and practical problem in a psychopharmacological laboratory. In the quest for neural correlates of (drug-induced altered states of) consciousness, introspective accounts of test subjects play a crucial role in neuroimaging studies. Firsthand knowledge of the drugs' flamboyant effects provides researchers with a personal knowledge not communicated in scientific publications, but key to the conduct of their experiments. In many cases, the "psychedelic experience" draws scientists into the field and continues to inspire their self-image and way of life. By exploring these domains the paper points to a persistence of the subjective in contemporary neuropsychopharmacology.

New-found fundamentals of bacterial persistence.

Science.gov (United States)

Kint, Cyrielle I; Verstraeten, Natalie; Fauvart, Maarten; Michiels, Jan

2012-12-01

Persister cells display tolerance to high doses of bactericidal antibiotics and typically comprise a small fraction of a bacterial population. Recently, evidence was provided for a causal link between therapy failure and the presence of persister cells in chronic infections, underscoring the need for research on bacterial persistence. A series of recent breakthroughs have shed light on the multiplicity of persister genes, the contribution of gene expression noise to persister formation, the importance of active responses to antibiotic tolerance and heterogeneity among persister cells. Moreover, the development of in vivo model systems has highlighted the clinical relevance of persistence. This review discusses these recent advances and how this knowledge fundamentally changes the way in which we will perceive the problem of antibiotic tolerance in years to come. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Persistence of Profits in Azerbaijan's Banking System

Directory of Open Access Journals (Sweden)

K. Batu TUNAY

2015-06-01

Full Text Available In this research, the persistence of profits in Azerbaijan's banking sector in the short-run and the long-run is investigated. Although there are a lot of researches done in the case of different countries, enough study has been implemented for the case of Azerbaijan despite of its high speed economic growth. This research analysis continuity of profits by using system panel data method. Obtained results indicate that profits demonstrate no persistence or a little persistence. In this context, existence of competitive powers in the sector can be stated.

Short-term memory and dual task performance

Science.gov (United States)

Regan, J. E.

1982-01-01

Two hypotheses concerning the way in which short-term memory interacts with another task in a dual task situation are considered. It is noted that when two tasks are combined, the activity of controlling and organizing performance on both tasks simultaneously may compete with either task for a resource; this resource may be space in a central mechanism or general processing capacity or it may be some task-specific resource. If a special relationship exists between short-term memory and control, especially if there is an identity relationship between short-term and a central controlling mechanism, then short-term memory performance should show a decrement in a dual task situation. Even if short-term memory does not have any particular identity with a controlling mechanism, but both tasks draw on some common resource or resources, then a tradeoff between the two tasks in allocating resources is possible and could be reflected in performance. The persistent concurrence cost in memory performance in these experiments suggests that short-term memory may have a unique status in the information processing system.

PAQ: Persistent Adaptive Query Middleware for Dynamic Environments

Science.gov (United States)

Rajamani, Vasanth; Julien, Christine; Payton, Jamie; Roman, Gruia-Catalin

Pervasive computing applications often entail continuous monitoring tasks, issuing persistent queries that return continuously updated views of the operational environment. We present PAQ, a middleware that supports applications' needs by approximating a persistent query as a sequence of one-time queries. PAQ introduces an integration strategy abstraction that allows composition of one-time query responses into streams representing sophisticated spatio-temporal phenomena of interest. A distinguishing feature of our middleware is the realization that the suitability of a persistent query's result is a function of the application's tolerance for accuracy weighed against the associated overhead costs. In PAQ, programmers can specify an inquiry strategy that dictates how information is gathered. Since network dynamics impact the suitability of a particular inquiry strategy, PAQ associates an introspection strategy with a persistent query, that evaluates the quality of the query's results. The result of introspection can trigger application-defined adaptation strategies that alter the nature of the query. PAQ's simple API makes developing adaptive querying systems easily realizable. We present the key abstractions, describe their implementations, and demonstrate the middleware's usefulness through application examples and evaluation.

Inspection methods for physical protection Task III review of other agencies' physical security activities for research reactors

International Nuclear Information System (INIS)

In Task I of this project, the current Nuclear Regulatory Commission (NRC) position-on physical security practices and procedures at research reactors were reviewed. In the second task, a sampling of the physical security plans was presented and the three actual reactor sites described in the security plans were visited. The purpose of Task III is to review other agencies' physical security activities for research reactors. During this phase, the actions, procedures and policies of two domestic and two foreign agencies other than the NRC that relate to the research reactor community were examined. The agencies examined were: International Atomic Energy Agency; Canadian Atomic Energy Control Board; Department of Energy; and American Nuclear Insurers

Role of Prefrontal Persistent Activity in Working Memory

Science.gov (United States)

Riley, Mitchell R.; Constantinidis, Christos

2016-01-01

The prefrontal cortex is activated during working memory, as evidenced by fMRI results in human studies and neurophysiological recordings in animal models. Persistent activity during the delay period of working memory tasks, after the offset of stimuli that subjects are required to remember, has traditionally been thought of as the neural correlate of working memory. In the last few years several findings have cast doubt on the role of this activity. By some accounts, activity in other brain areas, such as the primary visual and posterior parietal cortex, is a better predictor of information maintained in visual working memory and working memory performance; dynamic patterns of activity may convey information without requiring persistent activity at all; and prefrontal neurons may be ill-suited to represent non-spatial information about the features and identity of remembered stimuli. Alternative interpretations about the role of the prefrontal cortex have thus been suggested, such as that it provides a top-down control of information represented in other brain areas, rather than maintaining a working memory trace itself. Here we review evidence for and against the role of prefrontal persistent activity, with a focus on visual neurophysiology. We show that persistent activity predicts behavioral parameters precisely in working memory tasks. We illustrate that prefrontal cortex represents features of stimuli other than their spatial location, and that this information is largely absent from early cortical areas during working memory. We examine memory models not dependent on persistent activity, and conclude that each of those models could mediate only a limited range of memory-dependent behaviors. We review activity decoded from brain areas other than the prefrontal cortex during working memory and demonstrate that these areas alone cannot mediate working memory maintenance, particularly in the presence of distractors. We finally discuss the discrepancy between

To meet new tasks of scientific research on uranium geology in new century

International Nuclear Information System (INIS)

Chen Zuyi

2000-01-01

The author analyses the new situation that the scientific research on uranium geology is facing in the coming new century, and proposes that the guiding idea of the scientific research on uranium geology is to coordinate the general policy of Bureau of Geology--to give the first priority to in-situ leachable sandstone-type uranium deposits. The specific tasks for the scientific research on uranium geology are: to implement regional evaluation and target area selection of in-situ leachable sandstone-type uranium deposits; to develop new techniques and methods of detecting buried in-situ leachable sandstone-type uranium deposits; to turn the genetic model of uranium deposit and deposit model to prospecting model; to strengthen the research on economic geology and the dynamic assessment system of uranium resources and to build up and improve the data base of Meso-Cenozoic basins and sandstone-type uranium deposits. In order to guarantee the successful implementation of the above tasks it is necessary for the Beijing Research Institute of Uranium Geology--the leading unit in scientific research on uranium geology to accelerate bringing up large numbers of young outstanding researchers; to have clear consciousness of market economy and product quality; to given play to advantages of qualified personnel, advanced equipment and modern technology

Issues Related to Student Persistence toward Graduation in Public Schools: A Research-Based Tool for Educators

Science.gov (United States)

Scott, Nancy L.; Fisher, Deanne L.; Fritz, Ronald D.

2012-01-01

This abstract focuses on a project report addressing persistence toward graduation. The product will provide a comprehensive resource for school district leaders to use in the identification of at-risk students and research based dropout prevention programs. With the passage of "No Child Left Behind in 2002" legislation has put a greater…

Issues Related to Student Persistence toward Graduation in Public Schools: A Research Based Tool for Educators

Science.gov (United States)

Fisher, Deanne L.; Fritz, Ronald D.; Scott, Nancy L.

2012-01-01

This abstract focuses on a project report addressing persistence toward graduation. The product will provide a comprehensive resource for school district leaders to use in the identification of at-risk students and research based dropout prevention programs. With the passage of "No Child Left Behind" in 2002 legislation has put a greater…

Prospective memory in young and older adults: the effects of task importance and ongoing task load.

Science.gov (United States)

Smith, Rebekah E; Hunt, R Reed

2014-01-01

Remembering to perform an action in the future, called prospective memory, often shows age-related differences in favor of young adults when tested in the laboratory. Recently Smith, Horn, and Bayen (2012; Aging, Neuropsychology, and Cognition, 19, 495) embedded a PM task in an ongoing color-matching task and manipulated the difficulty of the ongoing task by varying the number of colors on each trial of the task. Smith et al. found that age-related differences in PM performance (lower PM performance for older adults relative to young adults) persisted even when older adults could perform the ongoing task as well or better than the young adults. The current study investigates a possible explanation for the pattern of results reported by Smith et al. by including a manipulation of task emphasis: for half of the participants the prospective memory task was emphasize, while for the other half the ongoing color-matching task was emphasized. Older adults performed a 4-color version of the ongoing color-matching task, while young adults completed either the 4-color or a more difficult 6-color version of the ongoing task. Older adults failed to perform as well as the young adults on the prospective memory task regardless of task emphasis, even when older adults were performing as well or better than the young adults on the ongoing color-matching task. The current results indicate that the lack of an effect of ongoing task load on prospective memory task performance is not due to a perception that one or the other task is more important than the other.

Modulation of the attentional span by foveal and parafoveal task load: An ERP study using attentional probes.

Science.gov (United States)

Kornrumpf, Benthe; Sommer, Werner

2015-09-01

Due to capacity limitation, visual attention must be focused to a limited region of the visual field. Nevertheless, it is assumed that the size of that region may vary with task demands. We aimed to obtain direct evidence for the modulation of visuospatial attention as a function of foveal and parafoveal task load. Participants were required to fixate the center word of word triplets. In separate task blocks, either just the fixated word or both the fixated and the parafoveal word to the right should be semantically classified. The spatiotemporal distribution of attention was assessed with task-irrelevant probes flashed briefly at center or parafoveal positions, during or in between word presentation trials. The N1 component of the ERP elicited by intertrial probes at possible target positions increased with task demands within a block. These results suggest the recruitment of additional attentional resources rather than a redistribution of a fixed resource pool, which persists across trials. © 2015 Society for Psychophysiological Research.

A Review of Research on Sport Education: 2004 to the Present

Science.gov (United States)

Hastie, Peter A.; de Ojeda, Diego Martinez; Luquin, Antonio Calderon

2011-01-01

Background: In 2005, Wallhead and O'Sullivan presented a review of research on the Sport Education model. In that review, the authors identified certain strengths of the model (particularly persistent team membership) in facilitating student engagement within student-centered learning tasks. Other areas (such as student leadership skills) were…

How to decode Unemployment Persistence: An econometric framework for identifying and comparing the sources of persistence

DEFF Research Database (Denmark)

Møller, Niels Framroze

2016-01-01

Most econometric analyses of persistence focus on the existence of non-stationary unemployment but not the origin of this. The present research contains a multivariate econometric framework for identifying and comparing different sources of unemployment persistence (e.g. hysteresis versus a slowly...... moving equilibrium rate). A small example, considering historical data (1988-2006) for the UK, demonstrates how the method can be applied in practice. Although this primarily serves as an illustration, the evidence clearly suggests that persistence was due to a slowly moving equilibrium (driven...

Application of productive research tasks in working with gifted students in teaching Serbian language and literature

Directory of Open Access Journals (Sweden)

Stakić Mirjana M.

2015-01-01

Full Text Available In the work we examine the possibility of application of productive research tasks in working with gifted students in teaching Serbian language and literature. Using specific examples of interpretations of literary works we show that productive research assignments encourage students' creative and inventive expression, creativity, imagination and criticality and enable them to develop in accordance with their personality, individual preferences and abilities. In the examples of their use in problem solving, we determine how productive research tasks are conducive to gifted students who need to learn through problem solving and school work and to experience learning as a challenge. They present the basis for independent research, which allows gifted students to express their own creativity and the need to acquire new, challenging knowledge, and represent a powerful motivational tool that teachers can use in order to further develop their talent. Creative application of the productive research tasks in teaching Serbian language and literature is the possibility that the education of gifted students is not treated as elitist question, but to transform teaching process into development of giftedness and talent, where the role of the teacher in the teaching process rises to the role of the mentor.

Task-related Interactions between Kindergarten Children and their Teachers : The Role of Emotional Security

NARCIS (Netherlands)

Thijs, Jochem T.; Koomen, Helma M.Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers’ support. Participants were 79

Task-related interactions between kindergarten children and their teachers: the role of emotional security.

NARCIS (Netherlands)

Thijs, J.T.; Koomen, H.M.Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers' support. Participants were 79

Cosmic radiation exposure and persistent cognitive dysfunction

Science.gov (United States)

Parihar, Vipan K.; Allen, Barrett D.; Caressi, Chongshan; Kwok, Stephanie; Chu, Esther; Tran, Katherine K.; Chmielewski, Nicole N.; Giedzinski, Erich; Acharya, Munjal M.; Britten, Richard A.; Baulch, Janet E.; Limoli, Charles L.

2016-01-01

The Mars mission will result in an inevitable exposure to cosmic radiation that has been shown to cause cognitive impairments in rodent models, and possibly in astronauts engaged in deep space travel. Of particular concern is the potential for cosmic radiation exposure to compromise critical decision making during normal operations or under emergency conditions in deep space. Rodents exposed to cosmic radiation exhibit persistent hippocampal and cortical based performance decrements using six independent behavioral tasks administered between separate cohorts 12 and 24 weeks after irradiation. Radiation-induced impairments in spatial, episodic and recognition memory were temporally coincident with deficits in executive function and reduced rates of fear extinction and elevated anxiety. Irradiation caused significant reductions in dendritic complexity, spine density and altered spine morphology along medial prefrontal cortical neurons known to mediate neurotransmission interrogated by our behavioral tasks. Cosmic radiation also disrupted synaptic integrity and increased neuroinflammation that persisted more than 6 months after exposure. Behavioral deficits for individual animals correlated significantly with reduced spine density and increased synaptic puncta, providing quantitative measures of risk for developing cognitive impairment. Our data provide additional evidence that deep space travel poses a real and unique threat to the integrity of neural circuits in the brain. PMID:27721383

Statistical Methods for the Analysis of Discrete Choice Experiments: A Report of the ISPOR Conjoint Analysis Good Research Practices Task Force.

Science.gov (United States)

Hauber, A Brett; González, Juan Marcos; Groothuis-Oudshoorn, Catharina G M; Prior, Thomas; Marshall, Deborah A; Cunningham, Charles; IJzerman, Maarten J; Bridges, John F P

2016-06-01

Conjoint analysis is a stated-preference survey method that can be used to elicit responses that reveal preferences, priorities, and the relative importance of individual features associated with health care interventions or services. Conjoint analysis methods, particularly discrete choice experiments (DCEs), have been increasingly used to quantify preferences of patients, caregivers, physicians, and other stakeholders. Recent consensus-based guidance on good research practices, including two recent task force reports from the International Society for Pharmacoeconomics and Outcomes Research, has aided in improving the quality of conjoint analyses and DCEs in outcomes research. Nevertheless, uncertainty regarding good research practices for the statistical analysis of data from DCEs persists. There are multiple methods for analyzing DCE data. Understanding the characteristics and appropriate use of different analysis methods is critical to conducting a well-designed DCE study. This report will assist researchers in evaluating and selecting among alternative approaches to conducting statistical analysis of DCE data. We first present a simplistic DCE example and a simple method for using the resulting data. We then present a pedagogical example of a DCE and one of the most common approaches to analyzing data from such a question format-conditional logit. We then describe some common alternative methods for analyzing these data and the strengths and weaknesses of each alternative. We present the ESTIMATE checklist, which includes a list of questions to consider when justifying the choice of analysis method, describing the analysis, and interpreting the results. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Minimal groups increase young children's motivation and learning on group-relevant tasks.

Science.gov (United States)

Master, Allison; Walton, Gregory M

2013-01-01

Three experiments (N = 130) used a minimal group manipulation to show that just perceived membership in a social group boosts young children's motivation for and learning from group-relevant tasks. In Experiment 1, 4-year-old children assigned to a minimal "puzzles group" persisted longer on a challenging puzzle than children identified as the "puzzles child" or children in a control condition. Experiment 2 showed that this boost in motivation occurred only when the group was associated with the task. In Experiment 3, children assigned to a minimal group associated with word learning learned more words than children assigned an analogous individual identity. The studies demonstrate that fostering shared motivations may be a powerful means by which to shape young children's academic outcomes. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Working memory benefits creative insight, musical improvisation, and original ideation through maintained task-focused attention.

Science.gov (United States)

De Dreu, Carsten K W; Nijstad, Bernard A; Baas, Matthijs; Wolsink, Inge; Roskes, Marieke

2012-05-01

Anecdotes from creative eminences suggest that executive control plays an important role in creativity, but scientific evidence is sparse. Invoking the Dual Pathway to Creativity Model, the authors hypothesize that working memory capacity (WMC) relates to creative performance because it enables persistent, focused, and systematic combining of elements and possibilities (persistence). Study 1 indeed showed that under cognitive load, participants performed worse on a creative insight task. Study 2 revealed positive associations between time-on-task and creativity among individuals high but not low in WMC, even after controlling for general intelligence. Study 3 revealed that across trials, semiprofessional cellists performed increasingly more creative improvisations when they had high rather than low WMC. Study 4 showed that WMC predicts original ideation because it allows persistent (rather than flexible) processing. The authors conclude that WMC benefits creativity because it enables the individual to maintain attention focused on the task and prevents undesirable mind wandering.

Getting a Grip on the Handgrip Task: Handgrip Duration Correlates with Neuroticism But Not Conscientiousness

Directory of Open Access Journals (Sweden)

Simon B. Goldberg

2017-08-01

Full Text Available Questions regarding the replicability of key findings in the self-regulation literature (e.g., ego-depletion effect have led some to call for a more thorough evaluation of commonly used measures of self-control. The isometric handgrip task is one such measure. The current study examined correlates of handgrip persistence using data drawn from a larger randomized controlled trial. Handgrip persistence was measured both at baseline and following a physical stressor (cold pressor test. Correlations were examined between handgrip performance and personality traits theoretically closely linked with self-regulation: conscientiousness and neuroticism. Baseline handgrip performance was correlated with several measures drawn from the nomological network of self-regulation including measures of trait neuroticism, mindfulness, anxiety sensitivity, perceived stress, and positive affect, although not with trait conscientiousness. Baseline handgrip predicted aversiveness experienced during the physical stressor, while changes in handgrip performance tracked changes in implicit and explicit negative affect (i.e., affective reactivity. These associations were largely maintained when controlling for variables highly correlated with overall grip strength (i.e., gender, height, and weight, although correlations separated by gender suggest associations were primarily driven by female participants. Results support future research using the handgrip task.

Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force--1.

Science.gov (United States)

Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

2012-01-01

Models--mathematical frameworks that facilitate estimation of the consequences of health care decisions--have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR Modeling Task Force reported in 2003 has led to a new Task Force, jointly convened with the Society for Medical Decision Making, and this series of seven articles presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; and dealing with uncertainty and validating and reporting models transparently. This overview article introduces the work of the Task Force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these articles includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Increasing Optimism Protects Against Pain-Induced Impairment in Task-Shifting Performance.

Science.gov (United States)

Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2017-04-01

Persistent pain can lead to difficulties in executive task performance. Three core executive functions that are often postulated are inhibition, updating, and shifting. Optimism, the tendency to expect that good things happen in the future, has been shown to protect against pain-induced performance deterioration in executive function updating. This study tested whether this protective effect of a temporary optimistic state by means of a writing and visualization exercise extended to executive function shifting. A 2 (optimism: optimism vs no optimism) × 2 (pain: pain vs no pain) mixed factorial design was conducted. Participants (N = 61) completed a shifting task once with and once without concurrent painful heat stimulation after an optimism or neutral manipulation. Results showed that shifting performance was impaired when experimental heat pain was applied during task execution, and that optimism counteracted pain-induced deterioration in task-shifting performance. Experimentally-induced heat pain impairs shifting task performance and manipulated optimism or induced optimism counteracted this pain-induced performance deterioration. Identifying psychological factors that may diminish the negative effect of persistent pain on the ability to function in daily life is imperative. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Selective attention to task-irrelevant emotional distractors is unaffected by the perceptual load associated with a foreground task.

Science.gov (United States)

Hindi Attar, Catherine; Müller, Matthias M

2012-01-01

A number of studies have shown that emotionally arousing stimuli are preferentially processed in the human brain. Whether or not this preference persists under increased perceptual load associated with a task at hand remains an open question. Here we manipulated two possible determinants of the attentional selection process, perceptual load associated with a foreground task and the emotional valence of concurrently presented task-irrelevant distractors. As a direct measure of sustained attentional resource allocation in early visual cortex we used steady-state visual evoked potentials (SSVEPs) elicited by distinct flicker frequencies of task and distractor stimuli. Subjects either performed a detection (low load) or discrimination (high load) task at a centrally presented symbol stream that flickered at 8.6 Hz while task-irrelevant neutral or unpleasant pictures from the International Affective Picture System (IAPS) flickered at a frequency of 12 Hz in the background of the stream. As reflected in target detection rates and SSVEP amplitudes to both task and distractor stimuli, unpleasant relative to neutral background pictures more strongly withdrew processing resources from the foreground task. Importantly, this finding was unaffected by the factor 'load' which turned out to be a weak modulator of attentional processing in human visual cortex.

Selective attention to task-irrelevant emotional distractors is unaffected by the perceptual load associated with a foreground task.

Directory of Open Access Journals (Sweden)

Catherine Hindi Attar

Full Text Available A number of studies have shown that emotionally arousing stimuli are preferentially processed in the human brain. Whether or not this preference persists under increased perceptual load associated with a task at hand remains an open question. Here we manipulated two possible determinants of the attentional selection process, perceptual load associated with a foreground task and the emotional valence of concurrently presented task-irrelevant distractors. As a direct measure of sustained attentional resource allocation in early visual cortex we used steady-state visual evoked potentials (SSVEPs elicited by distinct flicker frequencies of task and distractor stimuli. Subjects either performed a detection (low load or discrimination (high load task at a centrally presented symbol stream that flickered at 8.6 Hz while task-irrelevant neutral or unpleasant pictures from the International Affective Picture System (IAPS flickered at a frequency of 12 Hz in the background of the stream. As reflected in target detection rates and SSVEP amplitudes to both task and distractor stimuli, unpleasant relative to neutral background pictures more strongly withdrew processing resources from the foreground task. Importantly, this finding was unaffected by the factor 'load' which turned out to be a weak modulator of attentional processing in human visual cortex.

Rasagiline in the Treatment of the Persistent Negative Symptoms of Schizophrenia.

Science.gov (United States)

Buchanan, Robert W; Weiner, Elaine; Kelly, Deanna L; Gold, James M; Keller, William R; Waltz, James A; McMahon, Robert P; Gorelick, David A

2015-07-01

The current study examined the efficacy and safety of rasagiline, a selective MAO-B inhibitor, for the treatment of persistent negative symptoms. Sixty people with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, schizophrenia or schizoaffective disorder, who met a priori criteria for persistent negative symptoms, were randomized to receive rasagiline, 1mg/d (n = 31) or placebo (n = 29) in a 12-week, double-blind, placebo-controlled clinical trial. The Scale for the Assessment of Negative Symptoms (SANS) total score was used to assess change in negative symptoms. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), N-Back test, a probabilistic learning task, and a delayed discounting task were used to assess cognition. In a mixed model analysis of covariance (MM-ANCOVA), with time as a continuous variable, there was a significant treatment × time effect for SANS total score (F = 5.61(df = 1,40.3), P = .023). The treatment × time interaction effect was also significant for the SANS avolition subscale score (F(1,40.2) = 10.41, P = .002). In a post hoc MM-ANCOVA analyses, with time as a categorical variable, group differences were significant at week 12 for SANS total score (t(37.3) = 2.15; P = .04; d = -0.41) and SANS avolition subscale score (t(49.0) = 3.06; P = .004; d = -0.46). There was a significant difference in number of participants with a ≥20% reduction in SANS avolition score (χ(2)(1) = 10.94; P = .0009), but not in SANS total score (χ(2)(1) = 1.11; P = .29). There were no significant group differences on the RBANS, N-Back, probabilistic learning, or delayed discounting tasks. Study results support future studies of the utility of rasagiline for the treatment of negative symptoms, including avolition (clinicaltrials.gov trial number: NCT00492336). © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please

The Effect of "Massed" Task Repetitions on Complexity, Accuracy and Fluency: Does It Transfer to a New Task?

Science.gov (United States)

Ahmadian, Mohammad Javad

2011-01-01

To date, research results suggest that task repetition positively affects oral task performance. However, researchers have not yet shown the extension of the benefits of repeating the same task to performance of a new task. This article first provides an overview of the currently available research findings on task repetition and then presents the…

A new semantic vigilance task: vigilance decrement, workload, and sensitivity to dual-task costs.

Science.gov (United States)

Epling, Samantha L; Russell, Paul N; Helton, William S

2016-01-01

Cognitive resource theory is a common explanation for both the performance decline in vigilance tasks, known as the vigilance decrement, and the limited ability to perform multiple tasks simultaneously. The limited supply of cognitive resources may be utilized faster than they are replenished resulting in a performance decrement, or may need to be allocated among multiple tasks with some performance cost. Researchers have proposed both domain-specific, for example spatial versus verbal processing resources, and domain general cognitive resources. One challenge in testing the domain specificity of cognitive resources in vigilance is the current lack of difficult semantic vigilance tasks which reliably produce a decrement. In the present research, we investigated whether the vigilance decrement was found in a new abbreviated semantic discrimination vigilance task, and whether there was a performance decrement in said vigilance task when paired with a word recall task, as opposed to performed individually. As hypothesized, a vigilance decrement in the semantic vigilance task was found in both the single-task and dual-task conditions, along with reduced vigilance performance in the dual-task condition and reduced word recall in the dual-task condition. This is consistent with cognitive resource theory. The abbreviated semantic vigilance task will be a useful tool for researchers interested in determining the specificity of cognitive resources utilized in vigilance tasks.

Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

Science.gov (United States)

Azkarai, Agurtzane; García Mayo, María del Pilar

2017-01-01

Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

Research on Mathematics Teachers as Partners in Task Design

Science.gov (United States)

Jones, Keith; Pepin, Birgit

2016-01-01

Mathematical tasks and tools, including tasks in the form of digital tools, are key resources in mathematics teaching and in mathematics teacher education. Even so, the "design" of mathematical tasks is perceived in different ways: sometimes seen as something distinct from the teaching and learning process, and sometimes as integral to…

Task-Related Interactions between Kindergarten Children and Their Teachers: The Role of Emotional Security

Science.gov (United States)

Thijs, Jochem T.; Koomen, Helma M. Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers' support. Participants were 79 kindergartners (mean age = 69.7 months) and their…

Accelerator research studies: Progress report, Task B

International Nuclear Information System (INIS)

1985-06-01

The main objectives in Task B of the research program are summarized as follows: (1) studies of the collective acceleration of positive ions from a localized plasma source by an intense relativistic electron beam (IREB), (2) studies of ways in which external control may be achieved over the electron beam front in order to achieve higher ion energies - the Beam Front Accelerator (BFA) concept, and (3) study of electron and ion beam generation in a new kind of compact pulsed accelerator in which energy is stored inductively and switched using a plasma focus opening switch. During the past year, substantial progress was made in each of these areas. Our exploratory research on the collective acceleration of laser-produced ions has confirmed the acceleration of C, Al, and Fe ions to peak energies in excess of 10 MeV/amu. In addition, studies of the relation between collective ion acceleration and electron beam propagation in vacuum have shed new light on the experimental processes that lead to energy transfer from electrons to ions. Meanwhile, extensive progress has been made in our attempts to use analytical theory and numerical simulation to model ion acceleration in these systems. Our resultant improved understanding of the processes that limit the peak ion energy has had a profound impact on our plans for further research in this area. Studies of the Compact Pulsed Accelerator have included both ion and electron beam extraction from the device. Its potential to reduce the volume of pulse power sources by an order of magnitude has already been demonstrated, and plans are currently underway to scale the experiment up to voltages in the 1 MV range

Increased cognitive control after task conflict? Investigating the N-3 effect in task switching.

Science.gov (United States)

Schuch, Stefanie; Grange, James A

2018-05-25

Task inhibition is considered to facilitate switching to a new task and is assumed to decay slowly over time. Hence, more persisting inhibition needs to be overcome when returning to a task after one intermediary trial (ABA task sequence) than when returning after two or more intermediary trials (CBA task sequence). Schuch and Grange (J Exp Psychol Learn Mem Cogn 41:760-767, 2015) put forward the hypothesis that there is higher task conflict in ABA than CBA sequences, leading to increased cognitive control in the subsequent trial. They provided evidence that performance is better in trials following ABA than following CBA task sequences. Here, this effect of the previous task sequence ("N-3 effect") is further investigated by varying the cue-stimulus interval (CSI), allowing for short (100 ms) or long (900 ms) preparation time for the upcoming task. If increased cognitive control after ABA involves a better preparation for the upcoming task, the N-3 effect should be larger with long than short CSI. The results clearly show that this is not the case. In Experiment 1, the N-3 effect was smaller with long than short CSI; in Experiment 2, the N-3 effect was not affected by CSI. Diffusion model analysis confirmed previous results in the literature (regarding the effect of CSI and of the ABA-CBA difference); however, the N-3 effect was not unequivocally associated with any of the diffusion model parameters. In exploratory analysis, we also tested the alternative hypothesis that the N-3 effect involves more effective task shielding, which would be reflected in reduced congruency effects in trials following ABA, relative to trials following CBA; congruency effects did not differ between these conditions. Taken together, we can rule out two potential explanations of the N-3 effect: Neither is this effect due to enhanced task preparation, nor to more effective task shielding.

Persistence and amplitude of cigarette demand in relation to quit intentions and attempts.

Science.gov (United States)

O'Connor, Richard J; Heckman, Bryan W; Adkison, Sarah E; Rees, Vaughan W; Hatsukami, Dorothy K; Bickel, Warren K; Cummings, K Michael

2016-06-01

The cigarette purchase task (CPT) is a method that can be used to assess the relative value of cigarettes. Based on cigarettes purchased across a price range, five derived metrics (Omax, Pmax, breakpoint, intensity, and elasticity) can assess cigarette demand. A study with adolescent smokers found that these could be reduced to two latent factors: persistence (price insensitivity) and amplitude (volumetric consumption). We sought to replicate this structure with adult smokers and examine how these variables relate to cessation efforts. Web-based survey conducted in 2014 among adult (18 years and above) current daily cigarette smokers (N = 1194). Participants completed the CPT, Fagerstrom Test for Nicotine Dependence (FTND), reported past-year quit attempts, and future quit intentions. We included published scales assessing perceived prevalence of smoking, social reactivity, smoker identity, and risk perception. Our analysis supported two latent variables, persistence and amplitude, which correlated positively with FTND. Persistence was correlated with several psychosocial factors and was higher among those intending to quit very soon, but did not vary by number of past-year quit attempts. Amplitude differed across quit attempts and intention (p intention (OR = 0.76, p = 0.001). Persistence and amplitude factors characterized CPT data in adults, discriminated known groups (e.g., smokers by intentions to quit), and were positively associated with nicotine dependence. Factor scores also appear to relate to certain psychosocial factors, such as smoker identity and perceptions of risk. Future research should examine the predictive validity of these constructs.

Persistence of Women in Online Degree-Completion Programs

Directory of Open Access Journals (Sweden)

Terry Müller

2008-06-01

Full Text Available Although online courses at postsecondary institutions promise adults access, flexibility, and convenience, many barriers to online learning remain. This article presents findings from a qualitative case study, which explored the phenomenon of undergraduate and graduate women learners’ persistence in online degree-completion programs at a college in the Northeast of the United States. Research questions asked why women learners persisted or failed to persist, and how factors supporting or hindering persistence influenced learners. Interviews with a purposeful sample of 20 participants revealed the complexity of variables affecting learners’ persistence to graduation. Findings suggested that multiple responsibilities, insufficient interaction with faculty, technology, and coursework ranked highest as barriers to women’s persistence. Strong motivation to complete degrees, engagement in the learning community, and appreciation for the convenience of an online degree-completion option facilitated persistence.

Non-persistent pesticides removal in constructed wetlands

Science.gov (United States)

Tu, Yue; Jiang, Lei; Li, Haixiang

2018-03-01

The heavy use of non-persistent pesticides, resulting in the accumulation of environment and destroy the aquatic environment. This paper presents the research status of using CWs to treat non-persistent pesticides in water. The removal mechanisms are mainly physical deposition, chemical hydrolysis and plant absorption. Analysis of the factors that affect the removal effect are mainly the nature of pesticides, HRT, plants. Some scholars have proposed that secondary products of non-persistent pesticides may be more harmful to the environment, However, the relevant reports are scarce.

Is corruption really persistent?

NARCIS (Netherlands)

Seldadyo, H.; de Haan, J.

Theoretical and empirical research on corruption generally concludes that corruption is persistent. However, using International Country Risk Guide data for the period 1984-2008 for 101 countries, we find strong evidence that corruption changes over time. In the present study, corruption levels of

THE ROLE OF PERSISTENCE IN STUDENTS’ SELF-REALIZATION

Directory of Open Access Journals (Sweden)

Sergey I. Kudinov

2017-12-01

Full Text Available The paper analyzes the results of an empirical research obtained with the help of a sample of students. The research of persistence was carried out within the framework of the dispositional concept of personality traits and individuality by A. I. Krupnov. The techniques developed by A. I. Krupnov as well as the author’s test of persistence were used in the study. After allocating the levels of persistence, the features of self-realization were analyzed in each group of the respondents. The specificity of self-realization was revealed in the context of the author’s polysystemic concept, the author’s multidimensional questionnaire on personality’s self-realization (MQPSR was used as a diagnostic tool. The empirical study revealed statistically significant differences in the specifics of self-realization of the students with different levels of persistence manifestation. The respondents with a high level of persistence realize themselves more successfully in different spheres of life due to the obvious active behaviour, optimistic attitude, high motivation, creative methods and techniques of self-expression, internal self-regulation and constructive behavior. The students with low persistence lack successful self-realization because of passivity, pessimism, external locus of self-control, a high level of barriers and standard simple schemes of self-expression.

Task-Sharing Approaches to Improve Mental Health Care in Rural and Other Low-Resource Settings: A Systematic Review.

Science.gov (United States)

Hoeft, Theresa J; Fortney, John C; Patel, Vikram; Unützer, Jürgen

2018-12-01

Rural areas persistently face a shortage of mental health specialists. Task shifting, or task sharing, is an approach in global mental health that may help address unmet mental health needs in rural and other low-resource areas. This review focuses on task-shifting approaches and highlights future directions for research in this area. Systematic review on task sharing of mental health care in rural areas of high-income countries included: (1) PubMed, (2) gray literature for innovations not yet published in peer-reviewed journals, and (3) outreach to experts for additional articles. We included English language articles published before August 31, 2013, on interventions sharing mental health care tasks across a team in rural settings. We excluded literature: (1) from low- and middle-income countries, (2) involving direct transfer of care to another provider, and (3) describing clinical guidelines and shared decision-making tools. The review identified approaches to task sharing focused mainly on community health workers and primary care providers. Technology was identified as a way to leverage mental health specialists to support care across settings both within primary care and out in the community. The review also highlighted how provider education, supervision, and partnerships with local communities can support task sharing. Challenges, such as confidentiality, are often not addressed in the literature. Approaches to task sharing may improve reach and effectiveness of mental health care in rural and other low-resource settings, though important questions remain. We recommend promising research directions to address these questions. © 2017 National Rural Health Association.

Toward Rechargeable Persistent Luminescence for the First and Third Biological Windows via Persistent Energy Transfer and Electron Trap Redistribution.

Science.gov (United States)

Xu, Jian; Murata, Daisuke; Ueda, Jumpei; Viana, Bruno; Tanabe, Setsuhisa

2018-05-07

Persistent luminescence (PersL) imaging without real-time external excitation has been regarded as the next generation of autofluorescence-free optical imaging technology. However, to achieve improved imaging resolution and deep tissue penetration, developing new near-infrared (NIR) persistent phosphors with intense and long duration PersL over 1000 nm is still a challenging but urgent task in this field. Herein, making use of the persistent energy transfer process from Cr 3+ to Er 3+ , we report a novel garnet persistent phosphor of Y 3 Al 2 Ga 3 O 12 codoped with Er 3+ and Cr 3+ (YAG G:Er-Cr), which shows intense Cr 3+ PersL (∼690 nm) in the deep red region matching well with the first biological window (NIR-I, 650-950 nm) and Er 3+ PersL (∼1532 nm) in the NIR region matching well with the third biological window (NIR-III, 1500-1800 nm). The optical imaging through raw-pork tissues (thickness of 1 cm) suggests that the emission band of Er 3+ can achieve higher spatial resolution and more accurate signal location than that of Cr 3+ due to the reduced light scattering at longer wavelengths. Furthermore, by utilizing two independent electron traps with two different trap depths in YAG G:Er-Cr, the Cr 3+ /Er 3+ PersL can even be recharged in situ by photostimulation with 660 nm LED thanks to the redistribution of trapped electrons from the deep trap to the shallow one. Our results serve as a guide in developing promising NIR (>1000 nm) persistent phosphors for long-term optical imaging.

The Task Is Not Enough: Processing Approaches to Task-Based Performance

Science.gov (United States)

Skehan, Peter; Xiaoyue, Bei; Qian, Li; Wang, Zhan

2012-01-01

This article reports on three research studies, all of which concern second language task performance. The first focuses on planning, and compares on-line and strategic planning as well as task repetition. The second study examines the role of familiarity on task performance, and compares this with conventional strategic planning. The third study…

Report of the NIH Task Force on Research Standards for Chronic Low Back Pain†

Science.gov (United States)

Deyo, Richard A.; Dworkin, Samuel F.; Amtmann, Dagmar; Andersson, Gunnar; Borenstein, David; Carragee, Eugene; Carrino, John; Chou, Roger; Cook, Karon; DeLitto, Anthony; Goertz, Christine; Khalsa, Partap; Loeser, John; Mackey, Sean; Panagis, James; Rainville, James; Tosteson, Tor; Turk, Dennis; Von Korff, Michael; Weiner, Debra K.

2015-01-01

Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients’ lives. Such cLBP is often termed non-specific, and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. The NIH Pain Consortium therefore charged a Research Task Force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimal data set to describe research participants (drawing heavily on the PROMIS methodology); reporting “responder analyses” in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. The RTF believes these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of chronic low back pain. We expect the RTF recommendations will become a dynamic document, and undergo continual improvement. Perspective A Task Force was convened by the NIH Pain Consortium, with the goal of developing research standards for chronic low back pain. The results included recommendations for definitions, a minimal dataset, reporting outcomes, and future research. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. PMID:26388962

REPORT OF THE NIH TASK FORCE ON RESEARCH STANDARDS FOR CHRONIC LOW BACK PAIN

Science.gov (United States)

Deyo, Richard A.; Dworkin, Samuel F.; Amtmann, Dagmar; Andersson, Gunnar; Borenstein, David; Carragee, Eugene; Carrino, John; Chou, Roger; Cook, Karon; DeLitto, Anthony; Goertz, Christine; Khalsa, Partap; Loeser, John; Mackey, Sean; Panagis, James; Rainville, James; Tosteson, Tor; Turk, Dennis; Von Korff, Michael; Weiner, Debra K.

2014-01-01

Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients’ lives. Such cLBP is often termed non-specific, and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. The NIH Pain Consortium therefore charged a Research Task Force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimal data set to describe research participants (drawing heavily on the PROMIS methodology); reporting “responder analyses” in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. The RTF believes these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of chronic low back pain. We expect the RTF recommendations will become a dynamic document, and undergo continual improvement. Perspective A Task Force was convened by the NIH Pain Consortium, with the goal of developing research standards for chronic low back pain. The results included recommendations for definitions, a minimal dataset, reporting outcomes, and future research. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. PMID:24787228

Working memory in school-age children with and without a persistent speech sound disorder.

Science.gov (United States)

Farquharson, Kelly; Hogan, Tiffany P; Bernthal, John E

2017-03-17

The aim of this study was to explore the role of working memory processes as a possible cognitive underpinning of persistent speech sound disorders (SSD). Forty school-aged children were enrolled; 20 children with persistent SSD (P-SSD) and 20 typically developing children. Children participated in three working memory tasks - one to target each of the components in Baddeley's working memory model: phonological loop, visual spatial sketchpad and central executive. Children with P-SSD performed poorly only on the phonological loop tasks compared to their typically developing age-matched peers. However, mediation analyses revealed that the relation between working memory and a P-SSD was reliant upon nonverbal intelligence. These results suggest that co-morbid low-average nonverbal intelligence are linked to poor working memory in children with P-SSD. Theoretical and clinical implications are discussed.

Formative Research on the Simplifying Conditions Method (SCM) for Task Analysis and Sequencing.

Science.gov (United States)

Kim, YoungHwan; Reigluth, Charles M.

The Simplifying Conditions Method (SCM) is a set of guidelines for task analysis and sequencing of instructional content under the Elaboration Theory (ET). This article introduces the fundamentals of SCM and presents the findings from a formative research study on SCM. It was conducted in two distinct phases: design and instruction. In the first…

Is a "Complex" Task Really Complex? Validating the Assumption of Cognitive Task Complexity

Science.gov (United States)

Sasayama, Shoko

2016-01-01

In research on task-based learning and teaching, it has traditionally been assumed that differing degrees of cognitive task complexity can be inferred through task design and/or observations of differing qualities in linguistic production elicited by second language (L2) communication tasks. Without validating this assumption, however, it is…

Supporting Academic Persistence in Low-Skilled Adult Learners

Science.gov (United States)

O'Neill, Susan; Thomson, Margareta Maria

2013-01-01

The current literature review explores the factors that contribute to academic persistence for adult learners. The aim of the study is to identify current research-based strategies aimed at supporting learner persistence, particularly for low-skilled adults. Elements of three theoretical frameworks, namely, expectancy-value theory (EVT), goal…

The opportunity to collaborate increases preschoolers' motivation for challenging tasks.

Science.gov (United States)

Butler, Lucas P; Walton, Gregory M

2013-12-01

Collaborating on challenging endeavors is a foundation of human society. Recent research suggests that young children are not only motivated to cooperate with others-for instance, to help others accomplish their goals-but may also be motivated to collaborate with others-to pursue shared goals. However, a primary reason why collaboration is so important is because opportunities to collaborate can bring people together to work hard to overcome challenges. Two studies (N=70) tested whether the collaborative nature of an activity itself can cause preschoolers to enjoy challenging tasks more and to persist longer on them. To isolate the psychological feeling of collaboration, we tested this hypothesis by manipulating purely psychological cues of collaboration; in all cases, children worked while physically alone. Both studies found that such cues substantially increased preschoolers' motivation on a challenging puzzle, including their persistence on and liking for the puzzle, relative to two non-collaborative control conditions. We suggest that an early emerging drive to engage in shared collaborative activities leads children to find collaborative activities to be intrinsically motivating. This may represent an important basis of motivation as children embark on formal schooling. Copyright © 2013 Elsevier Inc. All rights reserved.

Recent tasks and status of National Research Institute for Radiobiology and Radiohygiene as TSO

International Nuclear Information System (INIS)

Pellet, S.

2007-01-01

The technical support function of the National Research Institute for Radiobiology and Radiohygiene has been introduced at the time of its establishment. In order to support the actual requirements the Institute carries on extended research in the fields of radiation protection and radiation biology participating in national and international projects. Supporting the proper performance of national radiation protection and safety tasks the Institute gives professional directives and expert opinions for decision processes of authorities. The Institutes main areas of radiation protection activity are: - Radiation-related licensing, inspection, record keeping; - assuring safety of radiation sources; - National Personal Dosimetry Service; - radiological monitoring of the environment; - preparedness for radiological incidents and accidents; - radiation protection training activities. The Institute has an accredited Testing Laboratory with nearly sixty examination protocols. Together with its Central Environmental Testing Laboratory, the Institute thus provides a significant support for both theoretical and practical accomplishment of the national radiation protection and safety tasks. (author)

The Persistence of Experience: Prior Attentional and Emotional State Affects Network Functioning in a Target Detection Task.

Science.gov (United States)

Stern, Emily R; Muratore, Alexandra F; Taylor, Stephan F; Abelson, James L; Hof, Patrick R; Goodman, Wayne K

2015-09-01

Efficient, adaptive behavior relies on the ability to flexibly move between internally focused (IF) and externally focused (EF) attentional states. Despite evidence that IF cognitive processes such as event imagination comprise a significant amount of awake cognition, the consequences of internal absorption on the subsequent recruitment of brain networks during EF tasks are unknown. The present functional magnetic resonance imaging (fMRI) study employed a novel attentional state switching task. Subjects imagined positive and negative events (IF task) or performed a working memory task (EF task) before switching to a target detection (TD) task also requiring attention to external information, allowing for the investigation of neural functioning during external attention based on prior attentional state. There was a robust increase of activity in frontal, parietal, and temporal regions during TD when subjects were previously performing the EF compared with IF task, an effect that was most pronounced following negative IF. Additionally, dorsolateral prefrontal cortex was less negatively coupled with ventromedial prefrontal and posterior cingulate cortices during TD following IF compared with EF. These findings reveal the striking consequences for brain activity following immersion in an IF attentional state, which have strong implications for psychiatric disorders characterized by excessive internal focus. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Persistence among Minority STEM Majors: A Phenomenological Study

Science.gov (United States)

Williams-Watson, Stacey

The United States needs to increase the number of science, technology, engineering, and math (STEM) graduates to remain competitive in the global market and maintain national security. Minority students, specifically African-American and Hispanic, are underrepresented in STEM fields. As the minority population continues to grow it is essential that higher education institutions improve minority students' persistence in STEM education. This study examined the problem of minority students' lack of persistence in STEM programs. The purpose of this qualitative transcendental phenomenological study was to describe the lived experiences that minority students perceived as contributing to their persistence in STEM. The central research question was: What are the lived experiences of minority STEM students that have contributed to their persistence in a STEM program? The sub-questions were: a) What led participants to majors in STEM?; b) What contributed to students' success and persistence in STEM?; and c) What advice do students have to offer? The researcher interviewed 12 minority STEM students and uncovered 10 themes that described the lived experiences of minority students' persistence in STEM programs. The themes were 1) Childhood experiences and interests; 2) Positive educational experiences in secondary school; 3) Self- motivation; 4) Positive experiences with professors; 5) Family encouragement and values; 6) Lack of minorities; 7) Lack of educational preparation; 8) The need for financial assistance; 9) Clubs and organizations; and 10) Friends within the major. The significance of these findings is the potential to produce changes in curricula, programs, and retention methods that may improve the persistence of minority students in STEM programs.

Resolving the Paradox of the Active User: Stable Suboptimal Performance in Interactive Tasks

National Research Council Canada - National Science Library

Fu, Wai-Tat; Gray, Wayne D

2004-01-01

...: Cognitive Aspects of Human Computer Interaction, Cambridge, MIT Press, MA, USA] the persistent use of inefficient procedures in interactive tasks by experienced or even expert users when demonstrably more efficient procedures exist...

Conjoint analysis applications in health--a checklist: a report of the ISPOR Good Research Practices for Conjoint Analysis Task Force.

Science.gov (United States)

Bridges, John F P; Hauber, A Brett; Marshall, Deborah; Lloyd, Andrew; Prosser, Lisa A; Regier, Dean A; Johnson, F Reed; Mauskopf, Josephine

2011-06-01

The application of conjoint analysis (including discrete-choice experiments and other multiattribute stated-preference methods) in health has increased rapidly over the past decade. A wider acceptance of these methods is limited by an absence of consensus-based methodological standards. The International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Good Research Practices for Conjoint Analysis Task Force was established to identify good research practices for conjoint-analysis applications in health. The task force met regularly to identify the important steps in a conjoint analysis, to discuss good research practices for conjoint analysis, and to develop and refine the key criteria for identifying good research practices. ISPOR members contributed to this process through an extensive consultation process. A final consensus meeting was held to revise the article using these comments, and those of a number of international reviewers. Task force findings are presented as a 10-item checklist covering: 1) research question; 2) attributes and levels; 3) construction of tasks; 4) experimental design; 5) preference elicitation; 6) instrument design; 7) data-collection plan; 8) statistical analyses; 9) results and conclusions; and 10) study presentation. A primary question relating to each of the 10 items is posed, and three sub-questions examine finer issues within items. Although the checklist should not be interpreted as endorsing any specific methodological approach to conjoint analysis, it can facilitate future training activities and discussions of good research practices for the application of conjoint-analysis methods in health care studies. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Vision based persistent localization of a humanoid robot for locomotion tasks

Directory of Open Access Journals (Sweden)

Martínez Pablo A.

2016-09-01

Full Text Available Typical monocular localization schemes involve a search for matches between reprojected 3D world points and 2D image features in order to estimate the absolute scale transformation between the camera and the world. Successfully calculating such transformation implies the existence of a good number of 3D points uniformly distributed as reprojected pixels around the image plane. This paper presents a method to control the march of a humanoid robot towards directions that are favorable for visual based localization. To this end, orthogonal diagonalization is performed on the covariance matrices of both sets of 3D world points and their 2D image reprojections. Experiments with the NAO humanoid platform show that our method provides persistence of localization, as the robot tends to walk towards directions that are desirable for successful localization. Additional tests demonstrate how the proposed approach can be incorporated into a control scheme that considers reaching a target position.

The Persistence of Long Work Hours

OpenAIRE

Robert Drago; David Black; Mark Wooden

2005-01-01

Previous research hypothesizes that long working hours are related to consumerism, the ideal worker norm, high levels of human capital, and a high cost-of-job-loss. The authors test these hypotheses using panel data on working hours for an Australian sample of full-time employed workers. Analyses include a static cross-sectional model and a persistence model for long hours over time. The results suggest that long hours (50 or more hours in a usual week) are often persistent, and provide stron...

Task demand, task management, and teamwork

Energy Technology Data Exchange (ETDEWEB)

Braarud, Per Oeivind; Brendryen, Haavar

2001-03-15

The current approach to mental workload assessment in process control was evaluated in 3 previous HAMMLAB studies, by analysing the relationship between workload related measures and performance. The results showed that subjective task complexity rating was related to team's control room performance, that mental effort (NASA-TLX) was weakly related to performance, and that overall activity level was unrelated to performance. The results support the argument that general cognitive measures, i.e., mental workload, are weakly related to performance in the process control domain. This implies that other workload concepts than general mental workload are needed for valid assessment of human reliability and for valid assessment of control room configurations. An assessment of task load in process control suggested that how effort is used to handle task demand is more important then the level of effort invested to solve the task. The report suggests two main workload related concepts with a potential as performance predictors in process control: task requirements, and the work style describing how effort is invested to solve the task. The task requirements are seen as composed of individual task demand and team demand. In a similar way work style are seen as composed of individual task management and teamwork style. A framework for the development of the concepts is suggested based on a literature review and experiences from HAMMLAB research. It is suggested that operational definitions of workload concepts should be based on observable control room behaviour, to assure a potential for developing performance-shaping factors. Finally an explorative analysis of teamwork measures and performance in one study indicated that teamwork concepts are related to performance. This lends support to the suggested development of team demand and teamwork style as elements of a framework for the analysis of workload in process control. (Author)

Laboratory diagnosis of persistent human chlamydial infection

Directory of Open Access Journals (Sweden)

Mirja ePuolakkainen

2013-12-01

Full Text Available Diagnostic assays for persistent chlamydial infection are much needed to conduct high-quality, large-scale studies investigating the persistent state in vivo, its disease associations and the response to therapy. Yet in most studies the distinction between acute and persistent infection is based on the interpretation of the data obtained by the assays developed to diagnose acute infections or on complex assays available for research only and/or difficult to establish for clinical use. Novel biomarkers for detection of persistent chlamydial infection are urgently needed. Chlamydial whole genome proteome arrays are now available and they can identify chlamydial antigens that are differentially expressed between acute infection and persistent infection. Utilizing these data will lead to the development of novel diagnostic assays. Carefully selected specimens from well-studied patient populations are clearly needed in the process of translating the proteomic data into assays useful for clinical practice. Before such antigens are identified and validated assays become available, we face a challenge of deciding whether the persistent infection truly induced appearance of the proposed marker or do we just base our diagnosis of persistent infection on the presence of the suggested markers. Consequently, we must bear this in mind when interpreting the available data.

The risk-benefit task of research ethics committees: An evaluation of current approaches and the need to incorporate decision studies methods

Directory of Open Access Journals (Sweden)

Bernabe Rosemarie D L C

2012-04-01

Full Text Available Abstract Background Research ethics committees (RECs are tasked to assess the risks and the benefits of a trial. Currently, two procedure-level approaches are predominant, the Net Risk Test and the Component Analysis. Discussion By looking at decision studies, we see that both procedure-level approaches conflate the various risk-benefit tasks, i.e., risk-benefit assessment, risk-benefit evaluation, risk treatment, and decision making. This conflation makes the RECs’ risk-benefit task confusing, if not impossible. We further realize that RECs are not meant to do all the risk-benefit tasks; instead, RECs are meant to evaluate risks and benefits, appraise risk treatment suggestions, and make the final decision. Conclusion As such, research ethics would benefit from looking beyond the procedure-level approaches and allowing disciplines like decision studies to be involved in the discourse on RECs’ risk-benefit task.

Why They Stay: Women Persisting in US Engineering Careers

Science.gov (United States)

Buse, Kathleen; Bilimoria, Diana; Perelli, Sheri

2013-01-01

Purpose: Women remain dramatically underrepresented in the engineering profession and far fewer women than men persist in the field. This study aims to identify individual and contextual factors that distinguish women who persist in engineering careers in the US. Design/methodology/approach: Qualitative research was conducted based on…

Multi-Attribute Task Battery - Applications in pilot workload and strategic behavior research

Science.gov (United States)

Arnegard, Ruth J.; Comstock, J. R., Jr.

1991-01-01

The Multi-Attribute Task (MAT) Battery provides a benchmark set of tasks for use in a wide range of lab studies of operator performance and workload. The battery incorporates tasks analogous to activities that aircraft crewmembers perform in flight, while providing a high degree of experimenter control, performance data on each subtask, and freedom to nonpilot test subjects. Features not found in existing computer based tasks include an auditory communication task (to simulate Air Traffic Control communication), a resource management task permitting many avenues or strategies of maintaining target performance, a scheduling window which gives the operator information about future task demands, and the option of manual or automated control of tasks. Performance data are generated for each subtask. In addition, the task battery may be paused and onscreen workload rating scales presented to the subject. The MAT Battery requires a desktop computer with color graphics. The communication task requires a serial link to a second desktop computer with a voice synthesizer or digitizer card.

Persistence of interest in science, technology, engineering and mathematics: An analysis of persisting and non-persisting students

Science.gov (United States)

White, Jeffry L.

While there has been an increase in enrollment, interest in science, technology, engineering, and mathematics (STEM) has been declining on college campuses since 1967. Higher enrollment does not transfer to an increase in the number of minorities in the STEM fields. The majority-minority enrollment ratio is nearly 2:1 but the gap widens to 4:1 when it comes to graduation. In fact, underrepresented minorities (URM) earned only 12% of the STEM degrees awarded in 1998. When the higher attrition and lower graduation rates of URM are scrutinized, upwards of 60% changed majors or dropped out of STEM. Further investigation reveals the most frequently cited reasons for departure were loss of initial interest, developed a greater interest in another field, or were turned off by the STEM disciplines. A primarily exploratory study was conducted into the conditions necessary for academic interest in the STEM fields to persist. A model based on student engagement (Astin, 1977) and interest operations (Prenzel, 1988a) theories was used with a random sample of URM at universities participating in the Ohio Science and Engineering Alliance. Survey research was employed to investigate interest development and the effect of student retention programs and activities on such interest. The latter part of the study could not be fully examined when 95% reported not utilizing retention services. For the section on interest, an online survey using a 5-point Likert scale was validated using principal components analysis. A binominal logistic regression was used to predict membership in one of two possible groups: persisters and students at-risk for not persisting. The major conclusions are: (1) While 3 variables (feelings, learning and difficulty) were statistically significant only one, feelings was substantively significant. (2) Persistence increased 80.9% for each 1-unit increase in feelings and 9.9% for learning. (3) Persistence decreased 19.8% for each one-unit increase in difficulty

Organization of Biomedical Data for Collaborative Scientific Research: A Research Information Management System.

Science.gov (United States)

Myneni, Sahiti; Patel, Vimla L

2010-06-01

Biomedical researchers often work with massive, detailed and heterogeneous datasets. These datasets raise new challenges of information organization and management for scientific interpretation, as they demand much of the researchers' time and attention. The current study investigated the nature of the problems that researchers face when dealing with such data. Four major problems identified with existing biomedical scientific information management methods were related to data organization, data sharing, collaboration, and publications. Therefore, there is a compelling need to develop an efficient and user-friendly information management system to handle the biomedical research data. This study evaluated the implementation of an information management system, which was introduced as part of the collaborative research to increase scientific productivity in a research laboratory. Laboratory members seemed to exhibit frustration during the implementation process. However, empirical findings revealed that they gained new knowledge and completed specified tasks while working together with the new system. Hence, researchers are urged to persist and persevere when dealing with any new technology, including an information management system in a research laboratory environment.

Comments on future tasks for Romanian research related to nuclear power

International Nuclear Information System (INIS)

Dumitrache, I.

2000-01-01

Four main research areas are identified: - nuclear safety, - waste management, - fuel cycles and - plant life management. A significant number of tasks are related to each of these areas. Unfortunately, the cost of the needed research is much too high for the current electricity planning of Romania. Up to now, the international co-operation in CANDU field was not very efficient. Canada, India, Korea and Argentina have distinct intentions related to the use of nuclear power potential. Romania is the only European country interested to investigate CANDU reactor problems. Consequently, the author believes that the future Romanian nuclear power research effort must be clearly divided in two main classes: a. CR = 'Concentrated Research' on specific subjects, aimed to a better understanding, and to a complete solving of the associated problems, when possible, and b. CAR = 'Covering Areas Research' to maintain and update the know-how needed in the nuclear power activities. A given research subject may successively pass from one class to another, if needed; however, for a given period of one-to-five years, the class must be stated for each project, from the beginning. No research effort must be planned in the first class, CR, if the needed resources (human, technical and financial) are not ensured. Usually, the power plant leaders and the Institute researchers wish to dedicate their efforts to investigation of the 'hot problems'. Apparently, they are always right. In fact, the allocation of human and financial resources must be based on a very careful evaluation of the 'conditions required for success'. Otherwise, instead of the needed solution, the research will probably offer' a significant number of original methods, successfully applied', 'a more detailed knowledge of phenomena', 'several patents', a few papers 'published or accepted for publication in world over recognized scientific journals' etc. Although valuable, such results are not accepted instead of the needed

Who opts out of a project for health promotion with incentives?: Empirical research on the effect of rewards to motivate persistence.

Science.gov (United States)

Okamoto, Shohei; Komamura, Kohei; Tanabe, Kai; Yokoyama, Noriko; Tsukao, Akiko; Chijiki, Shoko; Kuno, Shinya

2017-01-01

Objectives　Although providing incentives for a better lifestyle has been of increasing concern, there is insufficient evidence about its effect. Therefore, this research aims to discover new insights by verifying the effect of rewards to motivate persistence in a project for health promotion.Methods　A total of 7,622 participants of an incentivized project for health promotion (Wellness Point Project) were recruited from 6 municipalities in Japan, namely Tohoku, Chubu, Kanto, Kinki, and Chugoku, of which the 4,291 individuals who had the necessary information for estimation were analyzed. Persistence in the project was judged by whether there was information about daily steps and/or participation in some fitness classes every month for one year at most. In addition, we used the reason participants chose certain rewards in order to categorize the characteristic of rewards, and estimated opt-out hazard ratios from the project using survival time analysis. Furthermore, the estimation in the model included individual features such as age, education, status of physical activity before joining the project, lifestyles such as smoking, drinking, and so on.Results　A multivariate analysis reveals that those who had chosen a reward for regional contribution were more likely to opt out than those who had chosen a certain reward because it is close to cash. The opt-out hazard ratio was 1.63 (95% CI: 1.18-2.25) among men and 1.40 (95% CI: 1.08-1.81) among women. In addition, insufficient physical activity, smoking, working for men, and physical condition for women were associated with opt-out.Conclusions　This research verified that a reward that participants felt was close to cash, compared to the internal motivation of regional contribution, could enhance the persistence rate of the project. Moreover, it was found that not only giving incentives but also considering participants' conditions is necessary to enhance persistence.

How asymmetrical task dependence and task interdependence interact:an individual level study into the effects on affective reactions

OpenAIRE

Jong, Simon B. De; Bal, P. Matthijs

2014-01-01

Purpose – This study investigates whether research and practice on task design and work teams could benefit from a more nuanced perspective on task (inter)dependencies among team members. Prior research often overlooked that task interdependence captures the average exchange of resources, while asymmetrical task dependence captures the inequalities within an individual's work relationships. To date, no study on work teams has combined the two aspects. Design/methodology/approach – Data was ob...

How attention can create synaptic tags for the learning of working memories in sequential tasks.

Directory of Open Access Journals (Sweden)

Jaldert O Rombouts

2015-03-01

Full Text Available Intelligence is our ability to learn appropriate responses to new stimuli and situations. Neurons in association cortex are thought to be essential for this ability. During learning these neurons become tuned to relevant features and start to represent them with persistent activity during memory delays. This learning process is not well understood. Here we develop a biologically plausible learning scheme that explains how trial-and-error learning induces neuronal selectivity and working memory representations for task-relevant information. We propose that the response selection stage sends attentional feedback signals to earlier processing levels, forming synaptic tags at those connections responsible for the stimulus-response mapping. Globally released neuromodulators then interact with tagged synapses to determine their plasticity. The resulting learning rule endows neural networks with the capacity to create new working memory representations of task relevant information as persistent activity. It is remarkably generic: it explains how association neurons learn to store task-relevant information for linear as well as non-linear stimulus-response mappings, how they become tuned to category boundaries or analog variables, depending on the task demands, and how they learn to integrate probabilistic evidence for perceptual decisions.

Task-related Interactions between Kindergarten Children and their Teachers: The Role of Emotional Security

OpenAIRE

Thijs, Jochem T.; Koomen, Helma M.Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers’ support. Participants were 79 kindergartners (mean age = 69.7 months) and their 40 regular teachers. Children were selected to approach a normal distribution of social inhibition. Children and teachers were filmed during a dyad...

Integrated corridor management : phase I, concept development and foundational research. Task 3.4, identify integrated corridor management institutional strategies and administration

Science.gov (United States)

2006-04-12

Task 3 involves overall foundational research to further the understanding of various aspects of Integrated Corridor Management (ICM) and to identify integration issues needed to evaluate the feasibility of the ICM initiative. The focus of Task 3.4 a...

Work factors as predictors of persistent fatigue: a prospective study of nurses' aides.

Science.gov (United States)

Eriksen, W

2006-06-01

To identify work factors that predict persistent fatigue in nurses' aides. The sample comprised 5547 Norwegian nurses' aides, not on leave when they completed a mailed questionnaire in 1999. Of these, 4645 (83.7%) completed a second questionnaire 15 months later. The outcome measure was the occurrence of persistent fatigue, defined as having felt "usually fatigued" or "always fatigued" in daytime during the previous 14 days. In respondents without persistent fatigue at baseline, medium and high work demands, heavy smoking, being single, and having long term health problems were associated with increased risk of persistent fatigue at follow up. Medium and high rewards for well done work, medium levels of leadership fairness, and regular physical exercise were associated with reduced risk of persistent fatigue at follow up. In respondents with persistent fatigue at baseline, medium and high levels of positive challenges at work, high support from immediate superior, medium feedback about quality of one's work, and changes of work or work tasks that resulted in less heavy work or lower work pace were associated with increased odds of recovery (no persistent fatigue at follow up). Working in a nursing home and being intensely bothered by long term health problems were associated with reduced odds of recovery. High demands and lack of rewards at work may cause persistent fatigue in nurses' aides. Reduction of demands, adequate feedback, and mental stimulation in the form of support and positive challenges may facilitate recovery in those who have persistent fatigue. Leaders in the health services may be in a position to regulate factors that influence the level of fatigue in nurses' aides.

Search along persistent random walks

International Nuclear Information System (INIS)

Friedrich, Benjamin M

2008-01-01

Optimal search strategies and their implementations in biological systems are a subject of active research. Here we study a search problem which is motivated by the hunt of sperm cells for the egg. We ask for the probability for an active swimmer to find a target under the condition that the swimmer starts at a certain distance from the target. We find that success probability is maximal for a certain level of fluctuations characterized by the persistence length of the swimming path of the swimmer. We derive a scaling law for the optimal persistence length as a function of the initial target distance and search time by mapping the search on a polymer physics problem

Implicit mentalizing persists beyond early childhood and is profoundly impaired in children with autism spectrum conditions

Directory of Open Access Journals (Sweden)

Tobias Schuwerk

2016-10-01

Full Text Available Implicit mentalizing, a fast, unconscious and rigid way of processing other's mental states has recently received much interest in typical social cognitive development in early childhood and in adults with autism spectrum conditions (ASC. This research suggests that already infants implicitly mentalize, and that adults with ASC have a sustained implicit mentalizing deficit. Yet, we have only sparse empirical evidence on implicit mentalizing beyond early childhood, and deviations thereof in children with ASC. Here, we administered an implicit mentalizing eye tracking task to assess the sensitivity to false beliefs to a group of 8-year-old children with and without ASC, matched for chronological age, verbal and nonverbal IQ. As previous research suggested that presenting outcomes of belief-based actions leads to fast learning from experience and false belief-congruent looking behavior in adults with ASC, we were also interested in whether already children with ASC learn from such information. Our results provide support for a persistent implicit mentalizing ability in neurotypical development beyond early childhood. Further, they confirmed an implicit mentalizing deficit in children with ASC, even when they are closely matched to controls for explicit mentalizing skills. In contrast to previous findings with adults, no experience-based modulation of anticipatory looking was observed. It seems that children with ASC have not yet developed compensatory general purpose learning mechanisms. The observed intact explicit, but impaired implicit mentalizing in ASC, and correlation patterns between mentalizing tasks and executive function tasks, are in line with theories on two dissociable mentalizing systems.

Twitter web-service for soft agent reporting in persistent surveillance systems

Science.gov (United States)

Rababaah, Haroun; Shirkhodaie, Amir

2010-04-01

Persistent surveillance is an intricate process requiring monitoring, gathering, processing, tracking, and characterization of many spatiotemporal events occurring concurrently. Data associated with events can be readily attained by networking of hard (physical) sensors. Sensors may have homogeneous or heterogeneous (hybrid) sensing modalities with different communication bandwidth requirements. Complimentary to hard sensors are human observers or "soft sensors" that can report occurrences of evolving events via different communication devices (e.g., texting, cell phones, emails, instant messaging, etc.) to the command control center. However, networking of human observers in ad-hoc way is rather a difficult task. In this paper, we present a Twitter web-service for soft agent reporting in persistent surveillance systems (called Web-STARS). The objective of this web-service is to aggregate multi-source human observations in hybrid sensor networks rapidly. With availability of Twitter social network, such a human networking concept can not only be realized for large scale persistent surveillance systems (PSS), but also, it can be employed with proper interfaces to expedite rapid events reporting by human observers. The proposed technique is particularly suitable for large-scale persistent surveillance systems with distributed soft and hard sensor networks. The efficiency and effectiveness of the proposed technique is measured experimentally by conducting several simulated persistent surveillance scenarios. It is demonstrated that by fusion of information from hard and soft agents improves understanding of common operating picture and enhances situational awareness.

[Persistent diarrhea

Science.gov (United States)

Andrade, J A; Moreira, C; Fagundes Neto, U

2000-07-01

INTRODUCTION: Persistent diarrhea has high impact on infantile morbidity and mortality rates in developing countries. Several studies have shown that 3 to 20% of acute diarrheal episodes in children under 5 years of age become persistent. DEFINITION: Persistent diarrhea is defined as an episode that lasts more than 14 days. ETIOLOGY: The most important agents isolated in persistent diarrhea are: Enteropathogenic E. coli (EPEC), Salmonella, Enteroaggregative E. coli (EAEC), Klebisiella and Cryptosporidium. CLINICAL ASPECTS: In general, the clinical characteristics of patients with persistent diarrhea do not change with the pathogenic agent. Persistent diarrhea seems to represent the final result of a several insults a infant suffers that predisposes to a more severe episode of diarrhea due to a combination of host factors and high rates of enviromental contamination. Therefore, efforts should be made to promptly treat all episodes of diarrhea with apropriate follow-up. THERAPY: The aim of the treatment is to restore hydroelectrolytic deficits and to replace losses until the diarrheal ceases. It is possible in the majority of the cases, using oral rehydration therapy and erly an appropriate type of diet. PREVENTION: It is imperative that management strategies also focus on preventive aspects. The most effective diarrheal prevention strategy in young infants worldwide is promotion of exclusive breast feeding.

Developing Analytic Rating Guides for "TOEFL iBT"® Integrated Speaking Tasks. "TOEFL iBT"® Research Report, TOEFL iBT-20. ETS Research Report. RR-13-13

Science.gov (United States)

Jamieson, Joan; Poonpon, Kornwipa

2013-01-01

Research and development of a new type of scoring rubric for the integrated speaking tasks of "TOEFL iBT"® are described. These "analytic rating guides" could be helpful if tasks modeled after those in TOEFL iBT were used for formative assessment, a purpose which is different from TOEFL iBT's primary use for admission…

Abnormal lateralization of fine motor actions in Tourette syndrome persists into adulthood.

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D Martino

Full Text Available Youth with Tourette syndrome (TS exhibit, compared to healthy, abnormal ability to lateralize digital sequential tasks. It is unknown whether this trait is related to inter-hemispheric connections, and whether it is preserved or lost in patients with TS persisting through adult life. We studied 13 adult TS patients and 15 age-matched healthy volunteers. All participants undertook: 1 a finger opposition task, performed with the right hand (RH only or with both hands, using a sensor-engineered glove in synchrony with a metronome at 2 Hz; we calculated a lateralization index [(single RH-bimanual RH/single RH X 100 for percentage of correct movements (%CORR; 2 MRI-based diffusion tensor imaging and probabilistic tractography of inter-hemispheric corpus callosum (CC connections between supplementary motor areas (SMA and primary motor cortices (M1. We confirmed a significant increase in the %CORR in RH in the bimanual vs. single task in TS patients (p<0.001, coupled to an abnormal ability to lateralize finger movements (significantly lower lateralization index for %CORR in TS patients, p = 0.04. The %CORR lateralization index correlated positively with tic severity measured with the Yale Global Tic Severity Scale (R = 0.55;p = 0.04. We detected a significantly higher fractional anisotropy (FA in both the M1-M1 (p = 0.036 and the SMA-SMA (p = 0.018 callosal fibre tracts in TS patients. In healthy subjects, the %CORR lateralization index correlated positively with fractional anisotropy of SMA-SMA fibre tracts (R = 0.63, p = 0.02; this correlation was not significant in TS patients. TS patients exhibited an abnormal ability to lateralize finger movements in sequential tasks, which increased in accuracy when the task was performed bimanually. This abnormality persists throughout different age periods and appears dissociated from the transcallosal connectivity of motor cortical regions. The altered interhemispheric transfer of motor abilities in TS may be

Workplace for analysis of task performance

NARCIS (Netherlands)

Bos, J; Mulder, LJM; van Ouwerkerk, RJ; Maarse, FJ; Akkerman, AE; Brand, AN; Mulder, LJM

2003-01-01

In current research on mental workload and task performance a large gap exists between laboratory based studies and research projects in real life working practice. Tasks conducted within a laboratory environment often lack a strong resemblance with real life working situations. This paper presents

The relation between task characteristics, BI quality and task compatibility: An explorative study

DEFF Research Database (Denmark)

Gaardboe, Rikke; Jonasen, Tanja Svarre; Nyvang, Tom

2018-01-01

The purpose of this article is to investigate the relationship between task characteristics, business intelligence (BI) quality, and task compatibility. It is essential to investigate this relationship, as BI often builds up data from the organization's existing information systems, and thus......, is a supplement. In addition, there is a gap within existing research about task characteristics and BI. We conducted a survey of three companies, where 104 BI end users answered the questionnaire. Our findings reveal that BI users who experience high information quality solve difficult tasks, have a specified...

Adolescents' experience of complex persistent pain.

Science.gov (United States)

Sørensen, Kari; Christiansen, Bjørg

2017-04-01

Persistent (chronic) pain is a common phenomenon in adolescents. When young people are referred to a pain clinic, they usually have amplified pain signals, with pain syndromes of unconfirmed ethology, such as fibromyalgia and complex regional pain syndrome (CRPS). Pain is complex and seems to be related to a combination of illness, injury, psychological distress, and environmental factors. These young people are found to have higher levels of distress, anxiety, sleep disturbance, and lower mood than their peers and may be in danger of entering adulthood with mental and physical problems. In order to understand the complexity of persistent pain in adolescents, there seems to be a need for further qualitative research into their lived experiences. The aim of this study was to explore adolescents' experiences of complex persistent pain and its impact on everyday life. The study has an exploratory design with individual in-depth interviews with six youths aged 12-19, recruited from a pain clinic at a main referral hospital in Norway. A narrative approach allowed the informants to give voice to their experiences concerning complex persistent pain. A hermeneutic analysis was used, where the research question was the basis for a reflective interpretation. Three main themes were identified: (1) a life with pain and unpleasant bodily expressions; (2) an altered emotional wellbeing; and (3) the struggle to keep up with everyday life. The pain was experienced as extremely strong, emerging from a minor injury or without any obvious causation, and not always being recognised by healthcare providers. The pain intensity increased as the suffering got worse, and the sensation was hard to describe with words. Parts of their body could change in appearance, and some described having pain-attacks or fainting. The feeling of anxiety was strongly connected to the pain. Despair and uncertainty contributed to physical disability, major sleep problems, school absence, and withdrawal from

Physical Education-in-CLIL tasks. Determining tasks characteristics through the analysis of the diaries

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Josep Coral Mateu

2013-07-01

Full Text Available This article focuses on the characteristics of Physical Education-in-CLIL (PE-in-CLIL tasks. CLIL (Content and Language Integrated Learning is a teaching approach which uses foreign language as a tool to enhance the subject learning process. We connect PE-in-CLIL with key competences and we introduce the CLIL 4Cs framework. We establish the aims of the study, that is; to describe the features of tasks which are most suitable to PE-in-CLIL and identify integrated tasks which appeal most to learners. We use Action-Research and we collect data through diaries. The participants of the study were twenty-six learners of 5th grade of primary school. We described the strategies of rigour and quality applied and we analysed data using a qualitative data analysis software programme (NVivo. In the results, we identify both the tasks that appeal to students and the tasks that are developed successfully. In the conclusions, we provide teaching guidelines to plan successful PE-in-CLIL tasks that appeal to students. At this point, we emphasise tasks that combined both cooperative learning and oracy with motor activity and games. We also declare the necessity of incorporating scaffolding strategies in order to accommodate students’ linguistic needs and facilitate tasks development. Future CLIL research possibilities emerge in the Physical Education field of work.

Inefficient cognitive control in adult ADHD: evidence from trial-by-trial Stroop test and cued task switching performance

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Heuser Isabella

2007-08-01

Full Text Available Abstract Background Contemporary neuropsychological models of ADHD implicate impaired cognitive control as contributing to disorder characteristic behavioral deficiencies and excesses; albeit to varying degrees. While the traditional view of ADHD postulates a core deficiency in cognitive control processes, alternative dual-process models emphasize the dynamic interplay of bottom-up driven factors such as activation, arousal, alerting, motivation, reward and temporal processing with top-down cognitive control. However, neuropsychological models of ADHD are child-based and have yet to undergo extensive empirical scrutiny with respect to their application to individuals with persistent symptoms in adulthood. Furthermore, few studies of adult ADHD samples have investigated two central cognitive control processes: interference control and task-set coordination. The current study employed experimental chronometric Stroop and task switching paradigms to investigate the efficiency of processes involved in interference control and task-set coordination in ADHD adults. Methods 22 adults diagnosed with persistent ADHD (17 males and 22 matched healthy control subjects performed a manual trial-by-trial Stroop color-word test and a blocked explicitly cued task switching paradigm. Performance differences between neutral and incongruent trials of the Stroop task measured interference control. Task switching paradigm manipulations allowed for measurement of transient task-set updating, sustained task-set maintenance, preparatory mechanisms and interference control. Control analyses tested for the specificity of group × condition interactions. Results Abnormal processing of task-irrelevant stimulus features was evident in ADHD group performance on both tasks. ADHD group interference effects on the task switching paradigm were found to be dependent on the time allotted to prepare for an upcoming task. Group differences in sustained task-set maintenance and

Low Socioeconomic Status Men Persisting in College: A Phenomenological Study

Science.gov (United States)

Crichton, Dusten D.

2017-01-01

The purpose of this phenomenological study was to explore and to tell the stories of low socioeconomic status (SES) men in college who persisted beyond the halfway point of college at a Midwestern metropolitan university. Prior research suggested men from low socioeconomic status backgrounds matriculated and persisted in college at the lowest…

Persistent Identifiers in Earth science data management environments

Science.gov (United States)

Weigel, Tobias; Stockhause, Martina; Lautenschlager, Michael

2014-05-01

Globally resolvable Persistent Identifiers (PIDs) that carry additional context information (which can be any form of metadata) are increasingly used by data management infrastructures for fundamental tasks. The notion of a Persistent Identifier is originally an abstract concept that aims to provide identifiers that are quality-controlled and maintained beyond the life time of the original issuer, for example through the use of redirection mechanisms. Popular implementations of the PID concept are for example the Handle System and the DOI System based on it. These systems also move beyond the simple identification concept by providing facilities that can hold additional context information. Not only in the Earth sciences, data managers are increasingly attracted to PIDs because of the opportunities these facilities provide; however, long-term viable principles and mechanisms for efficient organization of PIDs and context information are not yet available or well established. In this respect, promising techniques are to type the information that is associated with PIDs and to construct actionable collections of PIDs. There are two main drivers for extended PID usage: Earth science data management middleware use cases and applications geared towards scientific end-users. Motivating scenarios from data management include hierarchical data and metadata management, consistent data tracking and improvements in the accountability of processes. If PIDs are consistently assigned to data objects, context information can be carried over to subsequent data life cycle stages much easier. This can also ease data migration from one major curation domain to another, e.g. from early dissemination within research communities to formal publication and long-term archival stages, and it can help to document processes across technical and organizational boundaries. For scientific end users, application scenarios include for example more personalized data citation and improvements in the

Assessing the persistence of pharmaceuticals in the aquatic environment: Challenges and needs

Directory of Open Access Journals (Sweden)

Qingwei Bu

2016-09-01

Full Text Available Chemical’s persistence is known to be an important parameter applied for decades to identify persistent organic pollutants in hazard and/or risk assessments. Nevertheless it is greatly challenged in the case of emerging contaminants such as pharmaceuticals because the persistence of these chemicals could be more affected by environmental conditions. This fact brings more challenges to the current system for evaluating the persistence of chemical contaminants. In this paper, challenges in assessing the persistence of pharmaceuticals were identified, and more importantly research needs were addressed based on the existing data and knowledge.

20 Years of persistent identifiers - Which systems are here to stay?

Science.gov (United States)

Klump, Jens; Huber, Robert; Lehnert, Kerstin

2016-04-01

Web-based persistent identifiers have been around for more than 20 years, a period long enough to start observing patterns of success and failure. Persistent identifiers were invented to address challenges arising from the distributed and disorganised nature of the internet, which not only allowed new technologies to emerge, it also made it difficult to maintain a persistent record of science. Persistent identifiers now allow unambiguous identification of resources on the net. The expectations were that persistent identifiers would lead to greater accessibility, transparency and reproducibility of research results. Over the past two decades a number of persistent identifier systems have been built, one of them being Digital Object Identifiers (DOI). While DOI were originally invented by the publishing industry, they quickly became an established way for the identification of research resources. At first, these resources referred to scholarly literature and related resources. Other identifier systems, some of them using DOI as an example, were developed as grass-roots efforts by the scientific community. The concept of using persistent identifiers has since been expanded to other, non-textual resources, like datasets (DOI, EPIC) and geological specimens (IGSN), and more recently to authors and contributors of scholarly works (ORCID), and to software and instruments. A common witticism states that "a great thing about standards is that there are so many to choose from." Setting up identifier systems is technically trivial. The real challenge lies in creating a governance system for the respective identifiers. Which systems will stand the test of time? Drawing on data from the Registry of Research Data Repositories (re3data.org) and our own experience in the field, this presentation looks at the history and adoption of existing identifier systems and how this gives us some indications towards factors influencing sustainability of these systems.

A collection of research reporting, theoretical analysis, and practical applications in science education: Examining qualitative research methods, action research, educator-researcher partnerships, and constructivist learning theory

Science.gov (United States)

Hartle, R. Todd

2007-12-01

Educator-researcher partnerships are increasingly being used to improve the teaching of science. Chapter 1 provides a summary of the literature concerning partnerships, and examines the justification of qualitative methods in studying these relationships. It also justifies the use of Participatory Action Research (PAR). Empirically-based studies of educator-researcher partnership relationships are rare despite investments in their implementation by the National Science Foundation (NSF) and others. Chapter 2 describes a qualitative research project in which participants in an NSF GK-12 fellowship program were studied using informal observations, focus groups, personal interviews, and journals to identify and characterize the cultural factors that influenced the relationships between the educators and researchers. These factors were organized into ten critical axes encompassing a range of attitudes, behaviors, or values defined by two stereotypical extremes. These axes were: (1) Task Dictates Context vs. Context Dictates Task; (2) Introspection vs. Extroversion; (3) Internal vs. External Source of Success; (4) Prior Planning vs. Implementation Flexibility; (5) Flexible vs. Rigid Time Sense; (6) Focused Time vs. Multi-tasking; (7) Specific Details vs. General Ideas; (8) Critical Feedback vs. Encouragement; (9) Short Procedural vs. Long Content Repetition; and (10) Methods vs. Outcomes are Well Defined. Another ten important stereotypical characteristics, which did not fit the structure of an axis, were identified and characterized. The educator stereotypes were: (1) Rapport/Empathy; (2) Like Kids; (3) People Management; (4) Communication Skills; and (5) Entertaining. The researcher stereotypes were: (1) Community Collaboration; (2) Focus Intensity; (3) Persistent; (4) Pattern Seekers; and (5) Curiosity/Skeptical. Chapter 3 summarizes the research presented in chapter 2 into a practical guide for participants and administrators of educator-researcher partnerships

Resistance to change and resurgence in humans engaging in a computer task.

Science.gov (United States)

Kuroda, Toshikazu; Cançado, Carlos R X; Podlesnik, Christopher A

2016-04-01

The relation between persistence, as measured by resistance to change, and resurgence has been examined with nonhuman animals but not systematically with humans. The present study examined persistence and resurgence with undergraduate students engaging in a computer task for points exchangeable for money. In Phase 1, a target response was maintained on a multiple variable-interval (VI) 15-s (Rich) VI 60-s (Lean) schedule of reinforcement. In Phase 2, the target response was extinguished while an alternative response was reinforced at equal rates in both schedule components. In Phase 3, the target and the alternative responses were extinguished. In an additional test of persistence (Phase 4), target responding was reestablished as in Phase 1 and then disrupted by access to videos in both schedule components. In Phases 2 and 4, target responding was more persistent in the Rich than in the Lean component. Also, resurgence generally was greater in the Rich than in the Lean component in Phase 3. The present findings with humans extend the generality of those obtained with nonhuman animals showing that higher reinforcement rates produce both greater persistence and resurgence, and suggest that common processes underlie response persistence and relapse. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Task Complexity, Task Conditions, and Task Difficulty on the Grammatical Accuracy of EFL Learners in Written Discourse

Directory of Open Access Journals (Sweden)

Saeideh Ahangari

2012-11-01

Full Text Available Different methods of language teaching have tried to help EFL learners to develop good language skills based on their various perspectives. Research findings have underscored the effect of using task types in promoting language skills in terms of accuracy in written discourse. Therefore, this study set out to investigate whether there is an evidence of correct use of simple past tense (Accuracy based on Task Complexity (Task type :Here-and now & There-and-then,Task Conditions (Gender: Male & Female, and Task Difficulty (Proficiency: Lower-intermediate & Intermediate. Sixty Iranian English learners in a language institute participated in the study and were assigned to four groups of lower-intermediate male, lower-intermediate female, intermediate male and intermediate female. Initial homogeneity of the groups was verified using two general proficiency tests; KET for lower-intermediate and PET for intermediate. All groups in here-and-now task type were asked to write a story using simple past based on a picture strip while for there-and-then task type the participants were supposed to write about their last birthday. The results from paired samples t-test, independent samples t-test and two-way ANOVA analysis of the written data revealed significant differences in performing task types, at different proficiency levels and interaction between them. The findings have significant pedagogical implications for EFL learners to understand the relationship among Task Complexity,Task Conditions, Task Difficulty and L2 written production leading to various degrees of Accuracy.

Evaluating the Cassandra NoSQL Database Approach for Genomic Data Persistency

Directory of Open Access Journals (Sweden)

Rodrigo Aniceto

2015-01-01

Full Text Available Rapid advances in high-throughput sequencing techniques have created interesting computational challenges in bioinformatics. One of them refers to management of massive amounts of data generated by automatic sequencers. We need to deal with the persistency of genomic data, particularly storing and analyzing these large-scale processed data. To find an alternative to the frequently considered relational database model becomes a compelling task. Other data models may be more effective when dealing with a very large amount of nonconventional data, especially for writing and retrieving operations. In this paper, we discuss the Cassandra NoSQL database approach for storing genomic data. We perform an analysis of persistency and I/O operations with real data, using the Cassandra database system. We also compare the results obtained with a classical relational database system and another NoSQL database approach, MongoDB.

Evaluating the Cassandra NoSQL Database Approach for Genomic Data Persistency

Science.gov (United States)

Aniceto, Rodrigo; Xavier, Rene; Guimarães, Valeria; Hondo, Fernanda; Holanda, Maristela; Walter, Maria Emilia; Lifschitz, Sérgio

2015-01-01

Rapid advances in high-throughput sequencing techniques have created interesting computational challenges in bioinformatics. One of them refers to management of massive amounts of data generated by automatic sequencers. We need to deal with the persistency of genomic data, particularly storing and analyzing these large-scale processed data. To find an alternative to the frequently considered relational database model becomes a compelling task. Other data models may be more effective when dealing with a very large amount of nonconventional data, especially for writing and retrieving operations. In this paper, we discuss the Cassandra NoSQL database approach for storing genomic data. We perform an analysis of persistency and I/O operations with real data, using the Cassandra database system. We also compare the results obtained with a classical relational database system and another NoSQL database approach, MongoDB. PMID:26558254

Evaluating the Cassandra NoSQL Database Approach for Genomic Data Persistency.

Science.gov (United States)

Aniceto, Rodrigo; Xavier, Rene; Guimarães, Valeria; Hondo, Fernanda; Holanda, Maristela; Walter, Maria Emilia; Lifschitz, Sérgio

2015-01-01

Rapid advances in high-throughput sequencing techniques have created interesting computational challenges in bioinformatics. One of them refers to management of massive amounts of data generated by automatic sequencers. We need to deal with the persistency of genomic data, particularly storing and analyzing these large-scale processed data. To find an alternative to the frequently considered relational database model becomes a compelling task. Other data models may be more effective when dealing with a very large amount of nonconventional data, especially for writing and retrieving operations. In this paper, we discuss the Cassandra NoSQL database approach for storing genomic data. We perform an analysis of persistency and I/O operations with real data, using the Cassandra database system. We also compare the results obtained with a classical relational database system and another NoSQL database approach, MongoDB.

Supporting complex search tasks

DEFF Research Database (Denmark)

Gäde, Maria; Hall, Mark; Huurdeman, Hugo

2015-01-01

, is fragmented at best. The workshop addressed the many open research questions: What are the obvious use cases and applications of complex search? What are essential features of work tasks and search tasks to take into account? And how do these evolve over time? With a multitude of information, varying from...

Hold it! The influence of lingering rewards on choice diversification and persistence.

Science.gov (United States)

Schulze, Christin; van Ravenzwaaij, Don; Newell, Ben R

2017-11-01

Learning to choose adaptively when faced with uncertain and variable outcomes is a central challenge for decision makers. This study examines repeated choice in dynamic probability learning tasks in which outcome probabilities changed either as a function of the choices participants made or independently of those choices. This presence/absence of sequential choice-outcome dependencies was implemented by manipulating a single task aspect between conditions: the retention/withdrawal of reward across individual choice trials. The study addresses how people adapt to these learning environments and to what extent they engage in 2 choice strategies often contrasted as paradigmatic examples of striking violation of versus nominal adherence to rational choice: diversification and persistent probability maximizing, respectively. Results show that decisions approached adaptive choice diversification and persistence when sufficient feedback was provided on the dynamic rules of the probabilistic environments. The findings of divergent behavior in the 2 environments indicate that diversified choices represented a response to the reward retention manipulation rather than to the mere variability of outcome probabilities. Choice in both environments was well accounted for by the generalized matching law, and computational modeling-based strategy analyses indicated that adaptive choice arose mainly from reliance on reinforcement learning strategies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The existence and persistence of long work hours

OpenAIRE

Drago, Robert William; Black, David; Wooden, Mark

2005-01-01

Previous research hypothesizes that long working hours are related to consumerism, the ideal worker norm, high levels of human capital, and a high cost-of-job-loss. The authors test these hypotheses using panel data on working hours for an Australian sample of full-time employed workers. Analyses include a static cross-sectional model and a persistence model for long hours over time. The results suggest that long hours (50 or more hours in a usual week) are often persistent, and provide stron...

Research on Multi - Person Parallel Modeling Method Based on Integrated Model Persistent Storage

Science.gov (United States)

Qu, MingCheng; Wu, XiangHu; Tao, YongChao; Liu, Ying

2018-03-01

This paper mainly studies the multi-person parallel modeling method based on the integrated model persistence storage. The integrated model refers to a set of MDDT modeling graphics system, which can carry out multi-angle, multi-level and multi-stage description of aerospace general embedded software. Persistent storage refers to converting the data model in memory into a storage model and converting the storage model into a data model in memory, where the data model refers to the object model and the storage model is a binary stream. And multi-person parallel modeling refers to the need for multi-person collaboration, the role of separation, and even real-time remote synchronization modeling.

The Persistence of Gender Differences in Political Interest

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TÀNIA VERGE MESTRE

2012-01-01

Full Text Available This article explores the role of individual resources, situational factors, and the socialization process in the persistence of a gender gap in political dispositions, principally in political interest. We pay special attention to situational factors, especially those related to the time devoted to housework and caring responsibilities. Despite the growing participation of women in the labor market and increasingly comparable levels of male and female educational attainment, the enduring unequal sexual division of household tasks reduces women?s time availability as well as the pool of skills, resources and social networks which could foster their political engagement, thus helping to sustain the gender gap in political interest.

Survival Processing and the Stroop Task

OpenAIRE

Stephanie A. Kazanas; Kendra M. Van Valkenburg; Jeanette Altarriba

2015-01-01

This study was designed to investigate the impact of survival processing with a novel task for this paradigm: the Stroop color-naming task. As the literature is mixed with regard to task generalizability, with survival processing promoting better memory for words, but not better memory for faces or paired associates, these types of task investigations are important to a growing field of research. Using the Stroop task provides a unique contribution, as identifying items by color is an importa...

The social transmission of metacontrol policies: Mechanisms underlying the interpersonal transfer of persistence and flexibility.

Science.gov (United States)

Hommel, Bernhard; Colzato, Lorenza S

2017-10-01

Humans often face binary cognitive-control dilemmas, with the choice between persistence and flexibility being a crucial one. Tackling these dilemmas requires metacontrol, i.e., the control of the current cognitive-control policy. As predicted from functional, psychometric, neuroscientific, and modeling approaches, interindividual variability in metacontrol biases towards persistence or flexibility could be demonstrated in metacontrol-sensitive tasks. These biases covary systematically with genetic predispositions regarding mesofrontal and nigrostriatal dopaminergic functioning and the individualistic or collectivistic nature of the cultural background. However, there is also evidence for mood- and meditation-induced intraindividual variability (with negative mood and focused-attention meditation being associated with a bias towards persistence, and positive mood and open-monitoring meditation being associated with a bias towards flexibility), suggesting that genetic and cultural factors do not determine metacontrol settings entirely. We suggest a theoretical framework that explains how genetic predisposition and cultural learning can lead to the implementation of metacontrol defaults, which however can be shifted towards persistence or flexibility by situational factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Control and Interference in Task Switching--A Review

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Kiesel, Andrea; Steinhauser, Marco; Wendt, Mike; Falkenstein, Michael; Jost, Kerstin; Philipp, Andrea M.; Koch, Iring

2010-01-01

The task-switching paradigm offers enormous possibilities to study cognitive control as well as task interference. The current review provides an overview of recent research on both topics. First, we review different experimental approaches to task switching, such as comparing mixed-task blocks with single-task blocks, predictable task-switching…

Task conflict in the Stroop task: When Stroop interference decreases as Stroop facilitation increases in a low task conflict context

Directory of Open Access Journals (Sweden)

Benjamin Andrew Parris

2014-10-01

Full Text Available In the present study participants completed two blocks of the Stroop task, one in which the Response-Stimulus Interval (RSI was 3500ms and one in which RSI was 200ms. It was expected that, in line with previous research, the shorter RSI would induce a low Task Conflict context by increasing focus on the colour identification goal in the Stroop task. Based on previous research showing the role of Task Conflict in the presence or absence Stroop facilitation, this was expected to lead to the novel finding of an increase in facilitation and simultaneous decrease in interference. Such a finding would be problematic for models of Stroop effects that predict these indices of performance should be affected in tandem. A crossover interaction is reported supporting these predictions. As predicted, the shorter RSI resulted in incongruent and congruent trial RTs decreasing relative to a static neutral baseline condition; hence interference decreased as facilitation increased. An explanatory model (expanding on the work of Goldfarb, Henik and colleagues is presented that: 1 Shows how under certain conditions the predictions from single mechanism models hold true (i.e. when Task conflict is held constant; 2 Shows how it is possible that interference can be affected by an experimental manipulation that leaves facilitation apparently untouched and; 3 Predicts that facilitation cannot be independently affected by an experimental manipulation.

[Accumulative effects and long-term persistence of subliminal mere exposure].

Science.gov (United States)

Kawakami, Naoaki; Yoshida, Fujio

2011-10-01

We examined the accumulative effects and long-term persistence of subliminal mere exposure. An accumulative exposure condition (100 exposures distributed over five days) and a massed exposure condition (100 exposures in one day) were used in a Go/No-go Association Task (GNAT), with assessments of likability from Time 1 (just after) to Time 6 (after three months). First, a single stimulus was shown subliminally for a total of 100 times. The results indicated that mere exposure effects occurred equally often at Time 1. However, after Time 2, likability gradually decreased under the massed exposure condition, while it did not decrease under the accumulative exposure condition until Time 6. Second, in order to investigate the effect of multiple exposure, five stimuli belonging to a common category were shown 20 times each, for a total of 100 times. An ANOVA suggested that massed exposure had an instantaneous effect on likability, whereas accumulative exposure had a long-term persistence effect. Also, multiple exposures strengthened the mere exposure effect.

The Effect of Focus on Form and Task Complexity on L2 Learners' Oral Task Performance

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Salimi, Asghar

2015-01-01

Second Language learners' oral task performance has been one of interesting and research generating areas of investigations in the field of second language acquisition specially, task-based language teaching and learning. The main purpose of the present study is to investigate the effect of focus on form and task complexity on L2 learners' oral…

Research on safety evaluation model for in-vehicle secondary task driving.

Science.gov (United States)

Jin, Lisheng; Xian, Huacai; Niu, Qingning; Bie, Jing

2015-08-01

This paper presents a new method for evaluating in-vehicle secondary task driving safety. There are five in-vehicle distracter tasks: tuning the radio to a local station, touching the touch-screen telephone menu to a certain song, talking with laboratory assistant, answering a telephone via Bluetooth headset, and finding the navigation system from Ipad4 computer. Forty young drivers completed the driving experiment on a driving simulator. Measures of fixations, saccades, and blinks are collected and analyzed. Based on the measures of driver eye movements which have significant difference between the baseline and secondary task driving conditions, the evaluation index system is built. The Analytic Network Process (ANP) theory is applied for determining the importance weight of the evaluation index in a fuzzy environment. On the basis of the importance weight of the evaluation index, Fuzzy Comprehensive Evaluation (FCE) method is utilized to evaluate the secondary task driving safety. Results show that driving with secondary tasks greatly distracts the driver's attention from road and the evaluation model built in this study could estimate driving safety effectively under different driving conditions. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Persistent Offenders in the North West of England, 1880-1940: Some Critical Research Questions

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David J. Cox, Steve Farrall and Barry Godfrey

2007-04-01

Full Text Available This article examines the concept of the persistent offender as a group within society, and the presumed impact of that discrete group upon society via a case study of offending in Crewe between 1880 and 1940. The findings of persistent offending in Crewe challenge the assumptions and prejudices of the period, about the links between unemployment and crime and the extent to which crime was an enduring ‘career’. There were no ‘hardened’ persistent offenders in the sample of the type envisaged by contemporary comment, though the role of drink in offending was sustained; and there was no clear ‘type’ of offender either. Examination of the life histories of a selection of offenders is shown to raise a number of interdisciplinary questions, challenging the assumptions of criminologists and legal scholars in relation to the role of legislation in the management of criminality, including the concept (of interest also to historians that reformation of the criminal was more achievable in the past than it is in the over-regulated present.

Do detour tasks provide accurate assays of inhibitory control?

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Whiteside, Mark A.; Laker, Philippa R.; Beardsworth, Christine E.

2018-01-01

Transparent Cylinder and Barrier tasks are used to purportedly assess inhibitory control in a variety of animals. However, we suspect that performances on these detour tasks are influenced by non-cognitive traits, which may result in inaccurate assays of inhibitory control. We therefore reared pheasants under standardized conditions and presented each bird with two sets of similar tasks commonly used to measure inhibitory control. We recorded the number of times subjects incorrectly attempted to access a reward through transparent barriers, and their latencies to solve each task. Such measures are commonly used to infer the differential expression of inhibitory control. We found little evidence that their performances were consistent across the two different Putative Inhibitory Control Tasks (PICTs). Improvements in performance across trials showed that pheasants learned the affordances of each specific task. Critically, prior experience of transparent tasks, either Barrier or Cylinder, also improved subsequent inhibitory control performance on a novel task, suggesting that they also learned the general properties of transparent obstacles. Individual measures of persistence, assayed in a third task, were positively related to their frequency of incorrect attempts to solve the transparent inhibitory control tasks. Neophobia, Sex and Body Condition had no influence on individual performance. Contrary to previous studies of primates, pheasants with poor performance on PICTs had a wider dietary breadth assayed using a free-choice task. Our results demonstrate that in systems or taxa where prior experience and differences in development cannot be accounted for, individual differences in performance on commonly used detour-dependent PICTS may reveal more about an individual's prior experience of transparent objects, or their motivation to acquire food, than providing a reliable measure of their inhibitory control. PMID:29593115

Differential effects of emotionally versus neutrally cued autobiographical memories on performance of a subsequent cognitive task: Effects of task difficulty

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Kymberly eYoung

2012-08-01

Full Text Available Attention is a limited resource, and in order to improve processing of the attended information, competing processes must be suppressed. Although it is well established that an experimentally induced change in mood state comprises one type of competing process that can impair performance on a subsequent task, no study has investigated whether an emotionally valenced autobiographical memory (AM also can alter performance on a subsequent task. We therefore examined the effects of AM recall on cognitive performance. Healthy participants (n=20 per experiment recalled AMs in response to positive, negative, and neutral cue words. Following each AM participants completed a simple perceptual task (Experiment 1 or solved moderately difficult subtraction problems (Experiment 2. In Experiment 1 participants performed less accurately following exposure to positive or negative versus neutral cue words (ps<0.001, and also were less accurate following negative versus positive cue words (p<0.001. In Experiment 2, in contrast, no difference in accuracy or response times reached statistical significance. Performance accuracy even trended towards being higher following exposure to negative versus neutral cue words (p=0.08. The results of Experiment 1 suggested that recalling emotionally salient AMs reduces the attention directed toward a simple continuous performance task administered immediately following the AM task, conceivably due to persistent contemplation of the AM. The negative results of Experiment 2 suggested that the effect of AMs on attention was attenuated, however, by increasing the difficulty of the subsequent task. Our results have implications for patients with MDD, as performing cognitively demanding tasks may allow them to attenuate the impairing effects of negative rumination on cognition.

Great Expectations: The Persistent Effect of Institutions on Culture

OpenAIRE

Litina, Anastasia

2014-01-01

This research exploits the event of immigration to establish that institutions have a persistent effect on culture. It is argued that immigrants coming from corrupt countries, tend to overtrust the institutions at the host country. This inflated trust of immigrants is documented as the Great Expectations effect. This result is interesting and intriguing for several reasons. First, it highlights the persistent effect of institutions (at the origin coun- try) on the cultural attitudes of immigr...

Persistent high job demands and reactivity to mental stress predict future ambulatory blood pressure.

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Steptoe, A; Cropley, M

2000-05-01

To test the hypothesis that work stress (persistent high job demands over 1 year) in combination with high reactivity to mental stress predict ambulatory blood pressure. Assessment of cardiovascular responses to standardized behavioural tasks, job demands, and ambulatory blood pressure over a working day and evening after 12 months. We studied 81 school teachers (26 men, 55 women), 36 of whom experienced persistent high job demands over 1 year, while 45 reported lower job demands. Participants were divided on the basis of high and low job demands, and high and low systolic pressure reactions to an uncontrollable stress task. Blood pressure and concurrent physical activity were monitored using ambulatory apparatus from 0900 to 2230 h on a working day. Cardiovascular stress reactivity was associated with waist/hip ratio. Systolic and diastolic pressure during the working day were greater in high job demand participants who were stress reactive than in other groups, after adjustment for age, baseline blood pressure, body mass index and negative affectivity. The difference was not accounted for by variations in physical activity. Cardiovascular stress reactivity and sustained psychosocial stress may act in concert to increase cardiovascular risk in susceptible individuals.

Beads task vs. box task: The specificity of the jumping to conclusions bias.

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Balzan, Ryan P; Ephraums, Rachel; Delfabbro, Paul; Andreou, Christina

2017-09-01

Previous research involving the probabilistic reasoning 'beads task' has consistently demonstrated a jumping-to-conclusions (JTC) bias, where individuals with delusions make decisions based on limited evidence. However, recent studies have suggested that miscomprehension may be confounding the beads task. The current study aimed to test the conventional beads task against a conceptually simpler probabilistic reasoning "box task" METHODS: One hundred non-clinical participants completed both the beads task and the box task, and the Peters et al. Delusions Inventory (PDI) to assess for delusion-proneness. The number of 'draws to decision' was assessed for both tasks. Additionally, the total amount of on-screen evidence was manipulated for the box task, and two new box task measures were assessed (i.e., 'proportion of evidence requested' and 'deviation from optimal solution'). Despite being conceptually similar, the two tasks did not correlate, and participants requested significantly less information on the beads task relative to the box task. High-delusion-prone participants did not demonstrate hastier decisions on either task; in fact, for box task, this group was observed to be significantly more conservative than low-delusion-prone group. Neither task was incentivized; results need replication with a clinical sample. Participants, and particularly those identified as high-delusion-prone, displayed a more conservative style of responding on the novel box task, relative to the beads task. The two tasks, whilst conceptually similar, appear to be tapping different cognitive processes. The implications of these results are discussed in relation to the JTC bias and the theoretical mechanisms thought to underlie it. Copyright © 2016 Elsevier Ltd. All rights reserved.

Performance Enhancements Under Dual-task Conditions

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Kramer, A. F.; Wickens, C. D.; Donchin, E.

1984-01-01

Research on dual-task performance has been concerned with delineating the antecedent conditions which lead to dual-task decrements. Capacity models of attention, which propose that a hypothetical resource structure underlies performance, have been employed as predictive devices. These models predict that tasks which require different processing resources can be more successfully time shared than tasks which require common resources. The conditions under which such dual-task integrality can be fostered were assessed in a study in which three factors likely to influence the integrality between tasks were manipulated: inter-task redundancy, the physical proximity of tasks and the task relevant objects. Twelve subjects participated in three experimental sessions in which they performed both single and dual-tasks. The primary task was a pursuit step tracking task. The secondary tasks required the discrimination between different intensities or different spatial positions of a stimulus. The results are discussed in terms of a model of dual-task integrality.

Effects of alcohol, initial gambling outcomes, impulsivity, and gambling cognitions on gambling behavior using a video poker task.

Science.gov (United States)

Corbin, William R; Cronce, Jessica M

2017-06-01

Drinking and gambling frequently co-occur, and concurrent gambling and drinking may lead to greater negative consequences than either behavior alone. Building on prior research on the effects of alcohol, initial gambling outcomes, impulsivity, and gambling cognitions on gambling behaviors using a chance-based (nonstrategic) slot-machine task, the current study explored the impact of these factors on a skill-based (strategic) video poker task. We anticipated larger average bets and greater gambling persistence under alcohol relative to placebo, and expected alcohol effects to be moderated by initial gambling outcomes, impulsivity, and gambling cognitions. Participants (N = 162; 25.9% female) were randomly assigned to alcohol (target BrAC = .08g%) or placebo and were given $10 to wager on a simulated video poker task, which was programmed to produce 1 of 3 initial outcomes (win, breakeven, or lose) before beginning a progressive loss schedule. Despite evidence for validity of the video poker task and alcohol administration paradigm, primary hypotheses were not supported. Individuals who received alcohol placed smaller wagers than participants in the placebo condition, though this effect was not statistically significant, and the direction of effects was reversed in at-risk gamblers (n = 41). These findings contradict prior research and suggest that alcohol effects on gambling behavior may differ by gambling type (nonstrategic vs. strategic games). Interventions that suggest alcohol is universally disinhibiting may be at odds with young adults' lived experience and thus be less effective than those that recognize the greater complexity of alcohol effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Judgment of facial expressions and depression persistence

NARCIS (Netherlands)

Hale, WW

1998-01-01

In research it has been demonstrated that cognitive and interpersonal processes play significant roles in depression development and persistence. The judgment of emotions displayed in facial expressions by depressed patients allows for a better understanding of these processes. In this study, 48

Irregular persistent activity induced by synaptic excitatory feedback

Directory of Open Access Journals (Sweden)

Francesca Barbieri

2007-11-01

Full Text Available Neurophysiological experiments on monkeys have reported highly irregular persistent activity during the performance of an oculomotor delayed-response task. These experiments show that during the delay period the coefficient of variation (CV of interspike intervals (ISI of prefrontal neurons is above 1, on average, and larger than during the fixation period. In the present paper, we show that this feature can be reproduced in a network in which persistent activity is induced by excitatory feedback, provided that (i the post-spike reset is close enough to threshold , (ii synaptic efficacies are a non-linear function of the pre-synaptic firing rate. Non-linearity between presynaptic rate and effective synaptic strength is implemented by a standard short-term depression mechanism (STD. First, we consider the simplest possible network with excitatory feedback: a fully connected homogeneous network of excitatory leaky integrate-and-fire neurons, using both numerical simulations and analytical techniques. The results are then confirmed in a network with selective excitatory neurons and inhibition. In both the cases there is a large range of values of the synaptic efficacies for which the statistics of firing of single cells is similar to experimental data.

The effect of episodic retrieval on inhibition in task switching.

Science.gov (United States)

Grange, James A; Kowalczyk, Agnieszka W; O'Loughlin, Rory

2017-08-01

Inhibition in task switching is inferred from n-2 repetition costs: the observation that ABA task switching sequences are responded to slower than CBA sequences. This is thought to reflect the persisting inhibition of Task A, which slows reactivation attempts. Mayr (2002) reported an experiment testing a critical noninhibitory account of this effect, namely episodic retrieval: If the trial parameters for Task A match across an ABA sequence, responses should be facilitated because of priming from episodic retrieval; a cost would occur if trial parameters mismatch. In a rule-switching paradigm, Mayr reported no significant difference in n-2 repetition cost when the trial parameters repeated or switched across an ABA sequence, in clear contrast to the episodic retrieval account. What remains unclear is whether successful episodic retrieval modulates the n-2 repetition cost. Across 3 experiments-including a close replication of Mayr-we find clear evidence of reduced n-2 task repetition costs when episodic retrieval is controlled. We find that the effect of episodic retrieval on the n-2 task repetition cost is increased when the cue-task relationship is made more abstract, suggesting the effect is because of interference in establishing the relevant attentional set. We also demonstrate that the episodic retrieval effect is not influenced by retrieval of low-level, perceptual, elements. Together, the data suggest the n-2 task repetition cost-typically attributable to an inhibitory mechanism-also reflects episodic retrieval effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Role of Rewarding and Novel Events in Facilitating Memory Persistence in a Separate Spatial Memory Task

Science.gov (United States)

Salvetti, Beatrice; Morris, Richard G. M.; Wang, Szu-Han

2014-01-01

Many insignificant events in our daily life are forgotten quickly but can be remembered for longer when other memory-modulating events occur before or after them. This phenomenon has been investigated in animal models in a protocol in which weak memories persist longer if exploration in a novel context is introduced around the time of memory…

The Creative task Creator: a tool for the generation of customized, Web-based creativity tasks.

Science.gov (United States)

Pretz, Jean E; Link, John A

2008-11-01

This article presents a Web-based tool for the creation of divergent-thinking and open-ended creativity tasks. A Java program generates HTML forms with PHP scripting that run an Alternate Uses Task and/or open-ended response items. Researchers may specify their own instructions, objects, and time limits, or use default settings. Participants can also be prompted to select their best responses to the Alternate Uses Task (Silvia et al., 2008). Minimal programming knowledge is required. The program runs on any server, and responses are recorded in a standard MySQL database. Responses can be scored using the consensual assessment technique (Amabile, 1996) or Torrance's (1998) traditional scoring method. Adoption of this Web-based tool should facilitate creativity research across cultures and access to eminent creators. The Creative Task Creator may be downloaded from the Psychonomic Society's Archive of Norms, Stimuli, and Data, www.psychonomic.org/archive.

Cogito ergo video: Task-relevant information is involuntarily boosted into awareness.

Science.gov (United States)

Gayet, Surya; Brascamp, Jan W; Van der Stigchel, Stefan; Paffen, Chris L E

2015-01-01

Only part of the visual information that impinges on our retinae reaches visual awareness. In a series of three experiments, we investigated how the task relevance of incoming visual information affects its access to visual awareness. On each trial, participants were instructed to memorize one of two presented hues, drawn from different color categories (e.g., red and green), for later recall. During the retention interval, participants were presented with a differently colored grating in each eye such as to elicit binocular rivalry. A grating matched either the task-relevant (memorized) color category or the task-irrelevant (nonmemorized) color category. We found that the rivalrous stimulus that matched the task-relevant color category tended to dominate awareness over the rivalrous stimulus that matched the task-irrelevant color category. This effect of task relevance persisted when participants reported the orientation of the rivalrous stimuli, even though in this case color information was completely irrelevant for the task of reporting perceptual dominance during rivalry. When participants memorized the shape of a colored stimulus, however, its color category did not affect predominance of rivalrous stimuli during retention. Taken together, these results indicate that the selection of task-relevant information is under volitional control but that visual input that matches this information is boosted into awareness irrespective of whether this is useful for the observer.

Evaluating task-based syllabus for EFL learners

Directory of Open Access Journals (Sweden)

Luu, Hoang Mai

2013-01-01

Full Text Available This research is an evaluation of the effectiveness of task-based syllabus on EFL learners’ language competence at a private university in Vietnam educational context. This research resorts to questionnaire survey, semi-structured interview, and pretest and posttest as instruments for data collection. The research findings revealed that a strength of the current task-based syllabus is the match between lesson topics and students’ expectations. However, the syllabus still created difficulties for students including insufficient vocabulary, unfamiliar structures, and lack of life knowledge. The effect of teaching with task-based syllabus on students’ language performance is also reflected through a significant difference in mean scores between the pretest and the posttest. This research provides an insight into the effectiveness of English teaching through task-based syllabus at a private university in Vietnam setting. It implies to teachers that they need to be sustainable change catalysts for more interesting syllabus for learners

Using Goal Setting and Task Analysis to Enhance Task-Based Language Learning and Teaching

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Rubin, Joan

2015-01-01

Task-Based Language Learning and Teaching has received sustained attention from teachers and researchers for over thirty years. It is a well-established pedagogy that includes the following characteristics: major focus on authentic and real-world tasks, choice of linguistic resources by learners, and a clearly defined non-linguistic outcome. This…

Engineering success: Undergraduate Latina women's persistence in an undergradute engineering program

Science.gov (United States)

Rosbottom, Steven R.

The purpose and focus of this narrative inquiry case study were to explore the personal stories of four undergraduate Latina students who persist in their engineering programs. This study was guided by two overarching research questions: a) What are the lived experiences of undergraduate Latina engineering students? b) What are the contributing factors that influence undergraduate Latina students to persist in an undergraduate engineering program? Yosso's (2005) community cultural wealth was used to the analyze data. Findings suggest through Yosso's (2005) aspirational capital, familial capital, social capital, navigational capital, and resistant capital the Latina student persisted in their engineering programs. These contributing factors brought to light five themes that emerged, the discovery of academic passions, guidance and support of family and teachers, preparation for and commitment to persistence, the power of community and collective engagement, and commitment to helping others. The themes supported their persistence in their engineering programs. Thus, this study informs policies, practices, and programs that support undergraduate Latina engineering student's persistence in engineering programs.

Search and Hyperlinking Task at MediaEval 2012

NARCIS (Netherlands)

Eskevich, Maria; Jones, Gareth J.F.; Chen, Shu; Aly, Robin; Ordelman, Roeland J.F.; Larson, Martha

2012-01-01

The Search and Hyperlinking Task was one of the Brave New Tasks at MediaEval 2012. The Task consisted of two sub- tasks which focused on search and linking in retrieval from a collection of semi-professional video content. These tasks followed up on research carried out within the MediaEval 2011

[A research program in neutrino physics, cosmic rays and elementary particles: Tasks A, B, C, D

International Nuclear Information System (INIS)

Sobel, H.W.

1991-01-01

A Summary of the DOE Supported High Energy Physics Research at The University of California, Irvine. Physics interests of the group are focused primarily on tests of conservation laws and studies of fundamental interactions between particles. There is also a significant interest in astrophysics and cosmic rays. The DOE support has been divided into four tasks briefly describes in this paper

Modulation of network excitability by persistent activity: how working memory affects the response to incoming stimuli.

Directory of Open Access Journals (Sweden)

Elisa M Tartaglia

2015-02-01

Full Text Available Persistent activity and match effects are widely regarded as neuronal correlates of short-term storage and manipulation of information, with the first serving active maintenance and the latter supporting the comparison between memory contents and incoming sensory information. The mechanistic and functional relationship between these two basic neurophysiological signatures of working memory remains elusive. We propose that match signals are generated as a result of transient changes in local network excitability brought about by persistent activity. Neurons more active will be more excitable, and thus more responsive to external inputs. Accordingly, network responses are jointly determined by the incoming stimulus and the ongoing pattern of persistent activity. Using a spiking model network, we show that this mechanism is able to reproduce most of the experimental phenomenology of match effects as exposed by single-cell recordings during delayed-response tasks. The model provides a unified, parsimonious mechanistic account of the main neuronal correlates of working memory, makes several experimentally testable predictions, and demonstrates a new functional role for persistent activity.

Considerations of persistence and security in CHOICES, an object-oriented operating system

Science.gov (United States)

Campbell, Roy H.; Madany, Peter W.

1990-01-01

The current design of the CHOICES persistent object implementation is summarized, and research in progress is outlined. CHOICES is implemented as an object-oriented system, and persistent objects appear to simplify and unify many functions of the system. It is demonstrated that persistent data can be accessed through an object-oriented file system model as efficiently as by an existing optimized commercial file system. The object-oriented file system can be specialized to provide an object store for persistent objects. The problems that arise in building an efficient persistent object scheme in a 32-bit virtual address space that only uses paging are described. Despite its limitations, the solution presented allows quite large numbers of objects to be active simultaneously, and permits sharing and efficient method calls.

Development of flight experiment task requirements. Volume 2: Technical Report. Part 2: Appendix H: Tasks-skills data series

Science.gov (United States)

Hatterick, G. R.

1972-01-01

The data sheets presented contain the results of the task analysis portion of the study to identify skill requirements of space shuttle crew personnel. A comprehensive data base is provided of crew functions, operating environments, task dependencies, and task-skills applicable to a representative cross section of earth orbital research experiments.

Persistence of airline accidents.

Science.gov (United States)

Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

2010-10-01

This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation. © 2010 The Author(s). Journal compilation © Overseas Development Institute, 2010.

A comparison of pet and purpose-bred research dog (Canis familiaris) performance on human-guided object-choice tasks.

Science.gov (United States)

Lazarowski, Lucia; Dorman, David C

2015-01-01

Several studies have shown that domestic dogs respond to human social cues such as pointing. Some experiments have shown that pet dogs outperformed wolves in following a momentary distal point. These findings have lent support to the hypothesis that domestication is responsible for domestic dogs' ability to utilize human gestures. Other studies demonstrating comparable performance in human-socialized wolves suggest this skill depends on experience with relevant human stimuli. However, domestic dogs lacking thorough exposure to humans are underrepresented in the comparative literature. The goal of this study was to evaluate pet and kennel-reared research domestic dogs on their ability to follow two types of point in an object-choice task. This study used young adult, intact male research dogs (n=11) and a comparison group of pet dogs living in human homes (n=9). We found that while pet dogs followed the momentary distal point above chance levels, research dogs did not. Both groups followed the simpler dynamic proximal point; however, pet dogs outperformed research dogs on this task. Our results indicate that ontogenetic experiences may influence a domestic dog's ability to use human gestures, highlighting the importance of testing different sub-populations of domestic dogs. Copyright © 2014 Elsevier B.V. All rights reserved.

A problem with problem solving: motivational traits, but not cognition, predict success on novel operant foraging tasks.

Science.gov (United States)

van Horik, Jayden O; Madden, Joah R

2016-04-01

Rates of innovative foraging behaviours and success on problem-solving tasks are often used to assay differences in cognition, both within and across species. Yet the cognitive features of some problem-solving tasks can be unclear. As such, explanations that attribute cognitive mechanisms to individual variation in problem-solving performance have revealed conflicting results. We investigated individual consistency in problem-solving performances in captive-reared pheasant chicks, Phasianus colchicus , and addressed whether success depends on cognitive processes, such as trial-and-error associative learning, or whether performances may be driven solely via noncognitive motivational mechanisms, revealed through subjects' willingness to approach, engage with and persist in their interactions with an apparatus, or via physiological traits such as body condition. While subjects' participation and success were consistent within the same problems and across similar tasks, their performances were inconsistent across different types of task. Moreover, subjects' latencies to approach each test apparatus and their attempts to access the reward were not repeatable across trials. Successful individuals did not improve their performances with experience, nor were they consistent in their techniques in repeated presentations of a task. However, individuals that were highly motivated to enter the experimental chamber were more likely to participate. Successful individuals were also faster to approach each test apparatus and more persistent in their attempts to solve the tasks than unsuccessful individuals. Our findings therefore suggest that individual differences in problem-solving success can arise from inherent motivational differences alone and hence be achieved without inferring more complex cognitive processes.

Team situation awareness in nuclear power plant process control: A literature review, task analysis and future research

International Nuclear Information System (INIS)

Ma, R.; Kaber, D. B.; Jones, J. M.; Starkey, R. L.

2006-01-01

Operator achievement and maintenance of situation awareness (SA) in nuclear power plant (NPP) process control has emerged as an important concept in defining effective relationships between humans and automation in this complex system. A literature review on factors influencing SA revealed several variables to be important to team SA, including the overall task and team goals, individual tasks, team member roles, and the team members themselves. Team SA can also be adversely affected by a range of factors, including stress, mental over- or under-loading, system design (including human-machine interface design), complexity, human error in perception, and automation. Our research focused on the analysis of 'shared' SA and team SA among an assumed three-person, main-control-room team. Shared SA requirements represent the knowledge that is held in common by NPP operators, and team SA represents the collective, unique knowledge of all operators. The paper describes an approach to goal-directed task analysis (GDTA) applied to NPP main control room operations. In general, the GDTA method reveals critical operator decision and information requirements. It identifies operator SA requirements relevant to performing complex systems control. The GDTA can reveal requirements at various levels of cognitive processing, including perception, comprehension and projection, in NPP process control. Based on the literature review and GDTA approach, a number of potential research issues are proposed with an aim toward understanding and facilitating team SA in NPP process control. (authors)

Rule knowledge aids performance on spatial and object alternation tasks by alcoholic patients with and without Korsakoff’s amnesia

Directory of Open Access Journals (Sweden)

Fiona J Bardenhagen

2007-01-01

Full Text Available Fiona J Bardenhagen1,2, Marlene Oscar-Berman3, Stephen C Bowden2,41School of Psychology, Victoria University, Melbourne, Victoria, Australia; 2Clinical Neurosciences, St. Vincent’s Hospital, Melbourne, Australia; 3Division of Psychiatry and Departments of Neurology and Anatomy and Neurobiology, Boston University School of Medicine; and Psychology Research Service, US Department of Veterans Affairs (VA Healthcare System, Jamaica Plain Campus, MA, USA; 4School of Behavioural Science, University of Melbourne, Parkville, Victoria, AustraliaAbstract: Delayed alternation (DA and object alternation (OA tasks traditionally have been used to measure defective response inhibition associated with dysfunction of frontal brain systems. However, these tasks are also sensitive to nonfrontal lesions, and cognitive processes such as the induction of rule-learning strategies also are needed in order to perform well on these tasks. Performance on DA and OA tasks was explored in 10 patients with alcohol-induced persisting amnestic disorder (Korsakoff’s syndrome, 11 abstinent long-term alcoholics, and 13 healthy non-alcoholic controls under each of two rule provision conditions: Alternation Rule and Correction Rule. Results confirmed that rule knowledge is a crucial cognitive component for solving problems such as DA and OA, and therefore, that errors on these tasks are not due to defective response inhibition alone. Further, rule-induction strategies were helpful to Korsakoff patients, despite their poorer performance on the tasks. These results stress the role of multiple cognitive abilities in successful performance on rule induction tasks. Evidence that these cognitive abilities are served by diffusely distributed neural networks should be considered when interpreting behavioral impairments on these tasks.Keywords: alcoholism, Korsakoff’s syndrome, comparative neuropsychology, perseveration, rule induction, working memory

Task conflict and proactive control: A computational theory of the Stroop task.

Science.gov (United States)

Kalanthroff, Eyal; Davelaar, Eddy J; Henik, Avishai; Goldfarb, Liat; Usher, Marius

2018-01-01

The Stroop task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to task-relevant information and inhibit automatic task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of task conflict. We first review the literature that shows RF variability in the Stroop task, both with regard to experimental manipulations and to individual differences. We suggest that task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop task, which includes the resolution of task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

DECOVALEX II PROJECT Technical Report - Task 2C

International Nuclear Information System (INIS)

Jing, L.; Stephansson, O.; Chijimatzu, M.; Tsang, C.F.

1999-05-01

The DECOVALEX II project is an international co-operative research project supported by a number of national radioactive waste management organizations of different countries. The project studied four tasks: Task 1: numerical simulation of the RCF3 pump test at Sellafield, UK; Task 2: numerical simulation of the in situ T-H-M experiment at Kamaishi Mine, Japan; Task 3: monitoring of current development in rock fracture research; and Task 4: report on treatment of T-H-M processes in Performance Assessment works for nuclear waste repositories. The project started in 1995 and is scheduled to be finalised in March, 1999. This report concerns the Task 2 of the DECOVALEX H project. Task 2 of the DECOVALEX II project is the numerical modelling of the in-situ T-H-M experiment of a fractured rock - buffer - heater system at Kamaishi Mine, Japan. The experiment was carried out inside a test pit drilled in the floor of a 5 x 7 m alcove excavated near an existing drift at the 550 m level. The test pit has a circular cross section of diameter 1.7 m and a depth of 5 m, filled with bentonite which contains an electric heater. Four research teams studied Task 2 with different computational models. The task is divided into three sub-tasks: Task 2A, Task 2B and Task 2C. Task 2A was defined as a blind prediction to the coupled hydro-mechanical behaviour of the fractured rocks due to the excavation of the test pit. The calibration of the numerical models against measured results of pore pressures, flow rates and rock deformation before filling up of the test pit formed Task 2B. These two sub-tasks were performed to establish well calibrated fields of hydraulic conductivity and mechanical deformability of the fractured rocks at the test site. They were necessary for further simulations on interactions between the rock and buffer materials during heating experiments, as required for Task 2C, with a higher level of confidence on rock mass models. Presented in this report is the

DECOVALEX II PROJECT Technical Report - Task 2C

Energy Technology Data Exchange (ETDEWEB)

Jing, L.; Stephansson, O. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Civil and Environmental Engineering; Boergesson, L. [Clay Technology AB, IDEON Research Center, Lund (Sweden); Chijimatzu, M. [Japan Nuclear Cycle Development Inst., Ibaraki (Japan). Waste Management and Fuel Cycle Research Center; Kautsky, F. [Swedish Nuclear Power Inspectorate (SKI), Stockholm (Sweden); Tsang, C.F. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States). Earth Science Div.

1999-05-01

The DECOVALEX II project is an international co-operative research project supported by a number of national radioactive waste management organizations of different countries. The project studied four tasks: Task 1: numerical simulation of the RCF3 pump test at Sellafield, UK; Task 2: numerical simulation of the in situ T-H-M experiment at Kamaishi Mine, Japan; Task 3: monitoring of current development in rock fracture research; and Task 4: report on treatment ofT-H-M processes in Performance Assessment works for nuclear waste repositories. The project started in 1995 and is scheduled to be finalised in March, 1999. This report concerns the Task 2 of the DECOVALEX H project. Task 2 of the DECOVALEX II project is the numerical modelling of the in-situ T-H-M experiment of a fractured rock - buffer - heater system at Kamaishi Mine, Japan. The experiment was carried out inside a test pit drilled in the floor of a 5 x 7 m alcove excavated near an existing drift at the 550 m level. The test pit has a circular cross section of diameter 1.7 m and a depth of 5 m, filled with bentonite which contains an electric heater. Four research teams studied Task 2 with different computational models. The task is divided into three sub-tasks: Task 2A, Task 2B and Task 2C. Task 2A was defined as a blind prediction to the coupled hydro-mechanical behaviour of the fractured rocks due to the excavation of the test pit. The calibration of the numerical models against measured results of pore pressures, flow rates and rock deformation before filling up of the test pit formed Task 2B. These two sub-tasks were performed to establish well calibrated fields of hydraulic conductivity and mechanical deformability of the fractured rocks at the test site. They were necessary for further simulations on interactions between the rock and buffer materials during heating experiments, as required for Task 2C, with a higher level of confidence on rock mass models. Presented in this report is the definition

Persistence of Mycoplasma genitalium following azithromycin therapy.

Directory of Open Access Journals (Sweden)

Catriona S Bradshaw

Full Text Available BACKGROUND: To determine clinical outcomes and cure rates for M.genitalium genital infection in men and women following azithromycin 1 g. METHODOLOGY: Patients attending Melbourne Sexual Health Centre between March 2005 and November 2007 with urethritis/epididymitis, cervicitis/pelvic inflammatory disease and sexual contacts of M.genitalium were tested for M.genitalium by polymerase chain reaction (PCR. M.genitalium-infection was treated with 1 g of azithromycin and a test-of-cure (toc was performed one month post-azithromycin. Response to azithromycin, and response to moxifloxacin (400 mg daily for 10 days in individuals with persistent infection post-azithromycin, was determined. PRINCIPAL FINDINGS: Of 1538 males and 313 females tested, 161 males (11% and 30 females (10% were infected with M.genitalium. A toc was available on 131 (69% infected individuals (median = 36 days [range 12-373]. Of 120 individuals prescribed azithromycin only pre-toc, M.genitalium was eradicated in 101 (84%, 95% confidence intervals [CI]: 77-90% and persisted in 19 (16%, 95% CI: 10-23%. Eleven individuals with persistent infection (9%, 95% CI: 5-15% had no risk of reinfection from untreated-partners, while eight (7%, 95% CI: 3-12% may have been at risk of reinfection from doxycycline-treated or untreated-partners. Moxifloxacin was effective in eradicating persistent infection in all cases not responding to azithromycin. Patients with persistent-M.genitalium were more likely to experience persistent symptoms (91%, compared to patients in whom M.genitalium was eradicated (17%, p<0.0001. CONCLUSION: Use of azithromycin 1 g in M.genitalium-infected patients was associated with unacceptable rates of persistent infection, which was eradicated with moxifloxacin. These findings highlight the importance of follow-up in M.genitalium-infected patients prescribed azithromycin, and the need to monitor for the development of resistance. Research to determine optimal first and

Persistence of undergraduate women in STEM fields

Science.gov (United States)

Pedone, Maggie Helene

fields. This longitudinal study showed that both pre-college and college level factors influenced undergraduate women's persistence in STEM. The research findings offer important implications for policy and practice initiatives in higher education that focus on the recruitment and retention of women in postsecondary STEM fields.

Secondary task for full flight simulation incorporating tasks that commonly cause pilot error: Time estimation

Science.gov (United States)

Rosch, E.

1975-01-01

The task of time estimation, an activity occasionally performed by pilots during actual flight, was investigated with the objective of providing human factors investigators with an unobtrusive and minimally loading additional task that is sensitive to differences in flying conditions and flight instrumentation associated with the main task of piloting an aircraft simulator. Previous research indicated that the duration and consistency of time estimates is associated with the cognitive, perceptual, and motor loads imposed by concurrent simple tasks. The relationships between the length and variability of time estimates and concurrent task variables under a more complex situation involving simulated flight were clarified. The wrap-around effect with respect to baseline duration, a consequence of mode switching at intermediate levels of concurrent task distraction, should contribute substantially to estimate variability and have a complex effect on the shape of the resulting distribution of estimates.

Reflections on Student Persistence

Directory of Open Access Journals (Sweden)

Vincent Tinto

2017-07-01

Full Text Available The Feature for this issue Reflections on Student Persistence has been prepared by Professor Vincent Tinto, Distinguished University Professor Emeritus at Syracuse University, United States of America (USA and a longtime friend and supporter of STARS. Vincent explores the case for motivation to be considered as a significant aspect of the tertiary student psyche by drawing on theoretical frameworks, research and practical experiences related to the issue. He synthesises this extensive, detailed, rich but often somewhat impenetrable data into a trilogy of clear and credible key dimensions of the motivation construct student self efficacy, sense of belonging and perceived value of the curriculum. This interpretation of the literature is a personal but informed reflection and is a timely piece which highlights the breadth and profundity of the presentations at this year's conference in Adelaide, Australia where students in all their diversity are central to our focus on enhancing the student experience. In this opening article, Vincent refers directly to the STARS papers selected for this Conference issue of the Journal which also address the importance of student persistence, self-efficacy and building the sense of belonging within their own institutional communities (Fernandes, Ford, Rayner & Pretorius; Kahu, Nelson, & Picton; McFarlane, Spes-Skrbis & Taib; Naylor; Smallhorn. Echoing his position on social justice and his advocacy for underserved students, Vincent reminds us that educational equity gaps still exist, and he encourages us to see the issue of persistence through the eyes of the students to support their perseverance and completion and thereby help reduce educational disadvantage.

Evaluating the Effects of Formal Corrective Feedback on Off-Task/On-Task Behavior of Mild Intellectually Disabled Students: An Action Research Study

Science.gov (United States)

George, Kevin

2016-01-01

The off-task behavior demonstrated by the study participants appears to interfere with classroom instruction, contribute to poor academic performance and in many instances lead to disciplinary actions such as suspension. The purpose of the study entailed determining if formal corrective feedback has an effect on the off-task/on-task behavior of…

Engineering education research: Impacts of an international network of female engineers on the persistence of Liberian undergraduate women studying engineering

Science.gov (United States)

Rimer, Sara; Reddivari, Sahithya; Cotel, Aline

2015-11-01

As international efforts to educate and empower women continue to rise, engineering educators are in a unique position to be a part of these efforts by encouraging and supporting women across the world at the university level through STEM education and outreach. For the past two years, the University of Michigan has been a part of a grassroots effort to encourage and support the persistence of engineering female students at University of Liberia. This effort has led to the implementation of a leadership camp this past August for Liberian engineering undergraduate women, meant to: (i) to empower engineering students with the skills, support, and inspiration necessary to become successful and well-rounded engineering professionals in a global engineering market; and (ii) to strengthen the community of Liberian female engineers by building cross-cultural partnerships among students resulting in a international network of women engineers. This session will present qualitative research findings on the impact of this grassroots effort on Liberian female students? persistence in engineering, and the future directions of this work.

RELATIONSHIP BETWEEN THE TASK AVERSIVENESS AND ACADEMIC PROCRASTINATION

Directory of Open Access Journals (Sweden)

Magvirasari Lestari Linra

2016-12-01

Full Text Available Academic procrastination occurs when certain tasks are considered unpleasant, an unpleasant task and the usual delayed them is the task of writing, reading, studying for the exam, meetings, and administrative. The purpose of this study was to determine the relationship of the task aversiveness with academic procrastination. Subject of the study were 100 students out of a population of 516 students of the Faculty of Psychology class of 2012-2014. The method used in this research is quantitative by using Spearman rho as data analysis techniques. The research instrument consists of academic procrastination scale and the scale of the task aversiveness. Based on the results of correlation is known that there is a positive relationship between task aversiveness with academic procrastination with a correlation coefficient r = 0.508; p = 0.000. The results showed that of the 100 students of the Faculty of Psychology University of Makassar has a degree of relationship between task aversiveness with academic procrastination is on the very low category (25, 8%. Area / types of tasks delayed is not necessarily an unpleasant task and otherwise unpleasant task may not be postponed. Area task the highest level of aversive and delays are areas the task of writing and reading. This study illustrates that academic procrastination can be lowered by a change in the mindset of an unpleasant task.

Frontal brain activation during a working memory task: a time-domain fNIRS study

Science.gov (United States)

Molteni, E.; Baselli, G.; Bianchi, A. M.; Caffini, M.; Contini, D.; Spinelli, L.; Torricelli, A.; Cerutti, S.; Cubeddu, R.

2009-02-01

We evaluated frontal brain activation during a working memory task with graded levels of difficulty in a group of 19 healthy subjects, by means of time-resolved fNIRS technique. Brain activation was computed, and was then separated into a "block-related" and a "tonic" components. Load-related increases of blood oxygenation were studied for the four different levels of task difficulty. Generalized Linear Models were applied to the data in order to explore the metabolic processes occurring during the mental effort and, possibly, their involvement in short term memorization. Results attest the presence of a persistent attentional-related metabolic activity, superimposed to a task-related mnemonic contribution. Moreover, a systemic component probably deriving from the extra-cerebral capillary bed was detected.

Numeric invariants from multidimensional persistence

Energy Technology Data Exchange (ETDEWEB)

Skryzalin, Jacek [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carlsson, Gunnar [Stanford Univ., Stanford, CA (United States)

2017-05-19

In this paper, we analyze the space of multidimensional persistence modules from the perspectives of algebraic geometry. We first build a moduli space of a certain subclass of easily analyzed multidimensional persistence modules, which we construct specifically to capture much of the information which can be gained by using multidimensional persistence over one-dimensional persistence. We argue that the global sections of this space provide interesting numeric invariants when evaluated against our subclass of multidimensional persistence modules. Lastly, we extend these global sections to the space of all multidimensional persistence modules and discuss how the resulting numeric invariants might be used to study data.

Persistent Aerial Tracking

KAUST Repository

Mueller, Matthias

2016-01-01

persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc

Iowa Gambling Task (IGT: Twenty Years After - Gambling Disorder and IGT

Directory of Open Access Journals (Sweden)

Damien eBrevers

2013-09-01

Full Text Available The Iowa Gambling Task (IGT involves probabilistic learning via monetary rewards and punishments, where advantageous task performance requires subjects to forego potential large immediate rewards for small longer-term rewards to avoid larger losses. Pathological gamblers perform worse on the IGT compared to controls, relating to their persistent preference toward high, immediate and uncertain rewards despite experiencing larger losses. In this contribution, we review studies that investigated processes associated with poor IGT performance in pathological gamblers. Findings from these studies seem to fit with recent neurocognitive models of addiction, which argue that the diminished ability of addicted individuals to ponder short-term against long-term consequences of a choice may be the product of an hyperactive automatic attentional and memory system for signaling the presence of addiction-related cues (e.g., high uncertain rewards associated with disadvantageous decks selection during the IGT and for attributing to such cues pleasure and excitement. This incentive-salience associated with gambling-related choice in pathological gamblers may be so high that it could literally hijack resources (hot executive functions involved in emotional self-regulation and necessary to allow the enactment of further elaborate decontextualized problem-solving abilities (cool executive functions. A framework for future research is also proposed, which highlights the need for studies examining how these processes contribute specifically to the aberrant choice profile displayed by pathological gamblers on the IGT.

DSaaS: A cloud service for persistent data structures

CSIR Research Space (South Africa)

Le Roux, PB

2016-04-01

Full Text Available 2CSIR/SU Centre for Artificial Intelligence Research pierrebleroux@gmail.com, kroon@sun.ac.za, whkbester@cs.sun.ac.za Keywords: DaaS, SaaS, Cloud Computing, Persistent Data Structure, Version...

Persistent villi hypoperfusion explains intramucosal acidosis in sheep endotoxemia

NARCIS (Netherlands)

Dubin, Arnaldo; Edul, Vanina Siham Kanoore; Pozo, Mario Omar; Murias, Gastón; Canullán, Carlos Manuel; Martins, Enrique Francisco; Ferrara, Gonzalo; Canales, Héctor Saul; Laporte, Mercedes; Estenssoro, Elisa; Ince, Can

2008-01-01

OBJECTIVE: To test the hypothesis that persistent villi hypoperfusion explains intramucosal acidosis after endotoxemic shock resuscitation. DESIGN: Controlled experimental study. SETTING: University-based research laboratory. SUBJECTS: A total of 14 anesthetized, mechanically ventilated sheep.

Impaired reward processing in the human prefrontal cortex distinguishes between persistent and remittent attention deficit hyperactivity disorder.

Science.gov (United States)

Wetterling, Friedrich; McCarthy, Hazel; Tozzi, Leonardo; Skokauskas, Norbert; O'Doherty, John P; Mulligan, Aisling; Meaney, James; Fagan, Andrew J; Gill, Michael; Frodl, Thomas

2015-11-01

Symptoms of attention deficit hyperactivity disorder (ADHD) in children often persist into adulthood and can lead to severe antisocial behavior. However, to-date it remains unclear whether neuro-functional abnormalities cause ADHD, which in turn can then provide a marker of persistent ADHD. Using event-related functional magnetic resonance imaging (fMRI), we measured blood oxygenation level dependent (BOLD) signal changes in subjects during a reversal learning task in which choice of the correct stimulus led to a probabilistically determined 'monetary' reward or punishment. Participants were diagnosed with ADHD during their childhood (N=32) and were paired with age, gender, and education matched healthy controls (N=32). Reassessment of the ADHD group as adults resulted in a split between either persistent (persisters, N=17) or remitted ADHDs (remitters, N=15). All three groups showed significantly decreased activation in the medial prefrontal cortex (PFC) and the left striatum during punished correct responses, however only remitters and controls presented significant psycho-physiological interaction between these fronto-striatal reward and outcome valence networks. Comparing persisters to remitters and controls showed significantly inverted responses to punishment (Pdifferent areas of the PFC for remitters compared with controls, suggesting that remitters might have learned compensation strategies to overcome their ADHD symptoms. Thus, fMRI helps understanding the neuro-functional basis of ADHD related behavior differences and differentiates between persistent and remittent ADHD. © 2015 Wiley Periodicals, Inc.

Prophages and growth dynamics confound experimental results with antibiotic-tolerant persister cells

DEFF Research Database (Denmark)

Harms, Alexander; Fino, Cinzia; Sørensen, Michael Askvad

2017-01-01

the validity of our model of persister formation in a refined assay setup that uses robust culture conditions and unravels the dynamics of persister cells through all bacterial growth stages. Our results confirm the importance of (p)ppGpp and Lon but no longer support a role of TA modules in E. coli persister......) modules. This model found considerable support among researchers studying persisters but also generated controversy as part of recent debates in the field. In this study, we therefore used our previous work as a model to critically examine common experimental procedures to understand and overcome......-tolerant persisters via induction of cryptic prophages. Similarly, the inadvertent infection of mutant strains with bacteriophage φ80, a notorious laboratory contaminant, apparently caused several of the phenotypes that we reported in our previous studies. We therefore reconstructed all infected mutants and probed...

Task-Related Modulations of BOLD Low-Frequency Fluctuations within the Default Mode Network

Science.gov (United States)

Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Assan, Ibrahim Eid; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico

2017-01-01

Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task. PMID:28845420

Task-Related Modulations of BOLD Low-Frequency Fluctuations within the Default Mode Network

Directory of Open Access Journals (Sweden)

Silvia Tommasin

2017-07-01

Full Text Available Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN, are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task.

Constructing experimental designs for discrete-choice experiments: report of the ISPOR Conjoint Analysis Experimental Design Good Research Practices Task Force.

Science.gov (United States)

Reed Johnson, F; Lancsar, Emily; Marshall, Deborah; Kilambi, Vikram; Mühlbacher, Axel; Regier, Dean A; Bresnahan, Brian W; Kanninen, Barbara; Bridges, John F P

2013-01-01

Stated-preference methods are a class of evaluation techniques for studying the preferences of patients and other stakeholders. While these methods span a variety of techniques, conjoint-analysis methods-and particularly discrete-choice experiments (DCEs)-have become the most frequently applied approach in health care in recent years. Experimental design is an important stage in the development of such methods, but establishing a consensus on standards is hampered by lack of understanding of available techniques and software. This report builds on the previous ISPOR Conjoint Analysis Task Force Report: Conjoint Analysis Applications in Health-A Checklist: A Report of the ISPOR Good Research Practices for Conjoint Analysis Task Force. This report aims to assist researchers specifically in evaluating alternative approaches to experimental design, a difficult and important element of successful DCEs. While this report does not endorse any specific approach, it does provide a guide for choosing an approach that is appropriate for a particular study. In particular, it provides an overview of the role of experimental designs for the successful implementation of the DCE approach in health care studies, and it provides researchers with an introduction to constructing experimental designs on the basis of study objectives and the statistical model researchers have selected for the study. The report outlines the theoretical requirements for designs that identify choice-model preference parameters and summarizes and compares a number of available approaches for constructing experimental designs. The task-force leadership group met via bimonthly teleconferences and in person at ISPOR meetings in the United States and Europe. An international group of experimental-design experts was consulted during this process to discuss existing approaches for experimental design and to review the task force's draft reports. In addition, ISPOR members contributed to developing a consensus

Measuring and explaining inflation persistence: disaggregate evidence on the Czech Republic

Czech Academy of Sciences Publication Activity Database

Babetskii, Ian; Coricelli, F.; Horváth, R.

-, č. 1 (2007), s. 1-36 Keywords : inflation dynamics * inflation targeting * persistence Subject RIV: AH - Economics http://www.cnb.cz/m2export/sites/www.cnb.cz/en/research/research_publications/cnb_wp/download/cnbwp_2007_01.pdf

Emerging Fabric of Science: Persistent Identifiers and Knowledge Networks

Science.gov (United States)

Hugo, W.

2017-12-01

There is an increasing emphasis on the use of persistent identifiers in the description of scientific activity, whether this is done to cite scholarly publications and research output, reliably identify role players such as funders and researchers, or to provide long-lasting references to controlled vocabulary. The ICSU World Data System has been promoting the establishment of a "Knowledge Network" to describe research activity, realising that parts of the network will be established as a federated `system', based on linkages between registries of persistent identifiers. In addition, there is a growing focus on not only the relationship between these major role players and associated digital objects, but also on the processes of science: provenance, reproducibility, and re-usability being significant topics of discussion. The paper will focus on description of the `Fabric of Science' from the perspectives of both structure and processes, review the state of implementation of real services and infrastructure in support of it. A case is made for inclusion of persistent identifiers into the mainstream activities of scientists and data infrastructure managers, and for the development of services, such as Scholix, to make better use of the relationships between digital objects and major role players. A proposal is made for the adoption of a federated system of services that are based on a hybrid graph-object framework similar to Scholix for recording the activity of scientific research. Finally, links to related ideas are explored: novel ways of representing of knowledge (such as Nanopublications) and the possibility that the publication paradigm currently in use may have to be amended.

Persistent angina

DEFF Research Database (Denmark)

Jespersen, L.; Abildstrom, S. Z.; Hvelplund, Anders

2013-01-01

To evaluate persistent angina in stable angina pectoris with no obstructive coronary artery disease (CAD) compared to obstructive CAD and its relation to long-term anxiety, depression, quality of life (QOL), and physical functioning. We invited 357 patients (men = 191; women = 166; response rate 83......-obstructive CAD or normal coronary arteries than in patients with obstructive CAD. Persistent angina symptoms were associated with long-term anxiety, depression, impaired physical functioning, and QOL irrespective of the degree of CAD. Contrary to common perception, excluding obstructive CAD in stable angina does...... %) with no prior cardiovascular disease who had a first-time coronary angiography (CAG) in 2008-2009 due to suspected stable angina to participate in a questionnaire survey in 2011 with the Seattle Angina Questionnaire and the Hospital Anxiety and Depression Scale as key elements. Long-term persistent angina (i...

On the importance of Task 1 and error performance measures in PRP dual-task studies

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects. PMID:25904890

On the importance of Task 1 and error performance measures in PRP dual-task studies.

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

Focus on Form in task-based language teaching

NARCIS (Netherlands)

van de Guchte, M.

2015-01-01

This dissertation presents research on the way in which learners focus on grammar in task-based language teaching (TBLT). Such a focus on grammar during meaningful task performance is called a Focus on Form (FonF). For this PhD research project we conducted three experimental studies which

Research study on the effects of illumination on performance of control room tasks

International Nuclear Information System (INIS)

Silverman, E.B.; Horst, R.L.; Parris, H.L.; O'Brien, J.

1990-01-01

The illumination in the control rooms of many operating nuclear plants falls below the levels specified in the NUREG-0700 guidelines. However, these guidelines are based on human perception and performance data which were acquired under laboratory conditions and with tasks very different from those typically found in control rooms. The objective of the present studies was to gather empirical data regarding the levels of illumination sufficient for performing tasks analogous to those performed in control rooms. Several tasks were designed to engage the perceptual and cognitive processes that are representative of actual control room performance. In a computerized laboratory test-bed, subjects scanned edgewise meters, examined hard-copy X-Y plots to discern the value of the displayed function at specific coordinates, and proofread hard-copy plant procedures. In a power plant control room simulator, data were likewise collected in a meter reading task and similar tasks representing elements of specific job-performance measures. For each task, response time and accuracy were measured under a range of illumination levels. Subjective comfort ratings were also obtained for each illumination level. The results from both settings indicated that with decreasing illumination, increased errors and/or longer response times occurred only for levels below ten footcandles, if at all. These data suggest that adequate performance in control room tasks can be achieved at illumination levels below those recommended in NUREG-0700

Research on air and missile defense task allocation based on extended contract net protocol

Science.gov (United States)

Zhang, Yunzhi; Wang, Gang

2017-10-01

Based on the background of air and missile defense distributed element corporative engagement, the interception task allocation problem of multiple weapon units with multiple targets under network condition is analyzed. Firstly, a mathematical model of task allocation is established by combat task decomposition. Secondly, the initialization assignment based on auction contract and the adjustment allocation scheme based on swap contract were introduced to the task allocation. Finally, through the simulation calculation of typical situation, the model can be used to solve the task allocation problem in complex combat environment.

Variable Persister Gene Interactions with (pppGpp for Persister Formation in Escherichia coli

Directory of Open Access Journals (Sweden)

Shuang Liu

2017-09-01

Full Text Available Persisters comprise a group of phenotypically heterogeneous metabolically quiescent bacteria with multidrug tolerance and contribute to the recalcitrance of chronic infections. Although recent work has shown that toxin-antitoxin (TA system HipAB depends on stringent response effector (pppGppin persister formation, whether other persister pathways are also dependent on stringent response has not been explored. Here we examined the relationship of (pppGpp with 15 common persister genes (dnaK, clpB, rpoS, pspF, tnaA, sucB, ssrA, smpB, recA, umuD, uvrA, hipA, mqsR, relE, dinJ using Escherichia coli as a model. By comparing the persister levels of wild type with their single gene knockout and double knockout mutants with relA, we divided their interactions into five types, namely A “dependent” (dnaK, recA, B “positive reinforcement” (rpoS, pspF, ssrA, recA, C “antagonistic” (clpB, sucB, umuD, uvrA, hipA, mqsR, relE, dinJ, D “epistasis” (clpB, rpoS, tnaA, ssrA, smpB, hipA, and E “irrelevant” (dnaK, clpB, rpoS, tnaA, sucB, smpB, umuD, uvrA, hipA, mqsR, relE, dinJ. We found that the persister gene interactions are intimately dependent on bacterial culture age, cell concentrations (diluted versus undiluted culture, and drug classifications, where the same gene may belong to different groups with varying antibiotics, culture age or cell concentrations. Together, this study represents the first attempt to systematically characterize the intricate relationships among the different mechanisms of persistence and as such provide new insights into the complexity of the persistence phenomenon at the level of persister gene network interactions.

Persistent spatial information in the frontal eye field during object-based short-term memory.

Science.gov (United States)

Clark, Kelsey L; Noudoost, Behrad; Moore, Tirin

2012-08-08

Spatial attention is known to gate entry into visual short-term memory, and some evidence suggests that spatial signals may also play a role in binding features or protecting object representations during memory maintenance. To examine the persistence of spatial signals during object short-term memory, the activity of neurons in the frontal eye field (FEF) of macaque monkeys was recorded during an object-based delayed match-to-sample task. In this task, monkeys were trained to remember an object image over a brief delay, regardless of the locations of the sample or target presentation. FEF neurons exhibited visual, delay, and target period activity, including selectivity for sample location and target location. Delay period activity represented the sample location throughout the delay, despite the irrelevance of spatial information for successful task completion. Furthermore, neurons continued to encode sample position in a variant of the task in which the matching stimulus never appeared in their response field, confirming that FEF maintains sample location independent of subsequent behavioral relevance. FEF neurons also exhibited target-position-dependent anticipatory activity immediately before target onset, suggesting that monkeys predicted target position within blocks. These results show that FEF neurons maintain spatial information during short-term memory, even when that information is irrelevant for task performance.

On the importance of Task 1 and error performance measures in PRP dual-task studies

Directory of Open Access Journals (Sweden)

Tilo eStrobach

2015-04-01

Full Text Available The Psychological Refractory Period (PRP paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and 2 are presented with variable stimulus onset asynchronies (SOAs and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e. decreasing SOAs do not increase RTs and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/ or error rates in Task 1. This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

Examining database persistence of ISO/EN 13606 standardized electronic health record extracts: relational vs. NoSQL approaches.

Science.gov (United States)

Sánchez-de-Madariaga, Ricardo; Muñoz, Adolfo; Lozano-Rubí, Raimundo; Serrano-Balazote, Pablo; Castro, Antonio L; Moreno, Oscar; Pascual, Mario

2017-08-18

The objective of this research is to compare the relational and non-relational (NoSQL) database systems approaches in order to store, recover, query and persist standardized medical information in the form of ISO/EN 13606 normalized Electronic Health Record XML extracts, both in isolation and concurrently. NoSQL database systems have recently attracted much attention, but few studies in the literature address their direct comparison with relational databases when applied to build the persistence layer of a standardized medical information system. One relational and two NoSQL databases (one document-based and one native XML database) of three different sizes have been created in order to evaluate and compare the response times (algorithmic complexity) of six different complexity growing queries, which have been performed on them. Similar appropriate results available in the literature have also been considered. Relational and non-relational NoSQL database systems show almost linear algorithmic complexity query execution. However, they show very different linear slopes, the former being much steeper than the two latter. Document-based NoSQL databases perform better in concurrency than in isolation, and also better than relational databases in concurrency. Non-relational NoSQL databases seem to be more appropriate than standard relational SQL databases when database size is extremely high (secondary use, research applications). Document-based NoSQL databases perform in general better than native XML NoSQL databases. EHR extracts visualization and edition are also document-based tasks more appropriate to NoSQL database systems. However, the appropriate database solution much depends on each particular situation and specific problem.

A design space of visualization tasks.

Science.gov (United States)

Schulz, Hans-Jörg; Nocke, Thomas; Heitzler, Magnus; Schumann, Heidrun

2013-12-01

Knowledge about visualization tasks plays an important role in choosing or building suitable visual representations to pursue them. Yet, tasks are a multi-faceted concept and it is thus not surprising that the many existing task taxonomies and models all describe different aspects of tasks, depending on what these task descriptions aim to capture. This results in a clear need to bring these different aspects together under the common hood of a general design space of visualization tasks, which we propose in this paper. Our design space consists of five design dimensions that characterize the main aspects of tasks and that have so far been distributed across different task descriptions. We exemplify its concrete use by applying our design space in the domain of climate impact research. To this end, we propose interfaces to our design space for different user roles (developers, authors, and end users) that allow users of different levels of expertise to work with it.

Atypical subtrochanteric and diaphyseal femoral fractures: report of a task force of the American Society for Bone and Mineral Research

DEFF Research Database (Denmark)

Shane, Elizabeth; Burr, David; Ebeling, Peter R

2010-01-01

Reports linking long-term use of bisphosphonates (BPs) with atypical fractures of the femur led the leadership of the American Society for Bone and Mineral Research (ASBMR) to appoint a task force to address key questions related to this problem. A multidisciplinary expert group reviewed pertinent...... published reports concerning atypical femur fractures, as well as preclinical studies that could provide insight into their pathogenesis. A case definition was developed so that subsequent studies report on the same condition. The task force defined major and minor features of complete and incomplete...

A Comparative Study of Task-based vs. Task- supported Teaching Approaches in an EFL Context

Directory of Open Access Journals (Sweden)

Mahdieh Shafipoor

2015-09-01

Full Text Available In spite of the numerous merits of task-based language instruction as claimed by its supporters in the last few decades, task-supported teaching approach as an alternative was introduced. Since then, there have been controversial debates over the superiority of each of these two approaches. Thus, in the current research project, the purpose was to consider these two teaching approaches in the scope of English language teaching, with the purpose of exploring the most efficient one in an Iranian EFL context. To this end, 120 sophomore students, majoring in English language translation course at Islamic Azad University, Shar-e-Qods branch were selected among 4 intact reading comprehension II classes. Next, they were divided into two experimental groups. The first experimental group received task-based instruction and for the second experimental group, task-trusted teaching approach was applied. The results of the data analyses turned out that task-trusted teaching approach was superior to task-based teaching in teaching reading to EFL learners.

Mining Tasks from the Web Anchor Text Graph: MSR Notebook Paper for the TREC 2015 Tasks Track

Science.gov (United States)

2015-11-20

Mining Tasks from the Web Anchor Text Graph: MSR Notebook Paper for the TREC 2015 Tasks Track Paul N. Bennett Microsoft Research Redmond, USA pauben...anchor text graph has proven useful in the general realm of query reformulation [2], we sought to quantify the value of extracting key phrases from...anchor text in the broader setting of the task understanding track. Given a query, our approach considers a simple method for identifying a relevant

Preliminary Research on the Verification Task of North Korea's Plutonium Declaration

International Nuclear Information System (INIS)

Kim, Hyun Chul; Park, Il Jin

2009-01-01

The denuclearization of North Korea seems challenging. North Korea has recognized itself as a nuclear weapon state by carrying out two nuclear tests while many other nations including South Korea have opposed North Korea's nuclear proliferation. As a result of longstanding negotiations, North Korea provided nearly 19,000 pages of operation history of three Yongbyon nuclear facilities on May 8, 2008 and a 60-page declaration of its nuclear activities and programs on June 26, 2008. However, one should notice that declaration documents are by themselves meaningless without their verification. To completely dismantle North Korea's nuclear programs, the verification task based on its declaration documents should be performed very thoroughly, considering the possibility of the presence of the undeclared nuclear materials and facilities. The verification task of North Korea's nuclear declaration consists of many broad themes to deal with, such as the review of declaration documents, the interview with facility operators, the sampling in the field, the laboratory analysis of the sample, data interpretation, and so on. One of the important themes is to verify North Korea's declared plutonium stockpile by comparing the declaration documents with measurement data which can be obtained from the sampling in the field and laboratory analysis. To prepare for the possible future verification of the declared plutonium stockpile, it is meaningful to give a thought on what data can be compared and what samples need to be taken and analyzed. In this study, we focus on the data to be compared and samples to be taken and analyzed for the plutonium accounting, as a preliminary research. To give a quantitative example, the nuclear material of the most recent North Korea's spent fuel rods discharged from the 5 MWe reactor is analyzed. On June 13, 2009, North Korea declared that more than one-third of the spent fuel rods had been reprocessed

CaMKII Requirement for in Vivo Insular Cortex LTP Maintenance and CTA Memory Persistence

Directory of Open Access Journals (Sweden)

Yectivani Juárez-Muñoz

2017-11-01

Full Text Available Calcium-calmodulin/dependent protein kinase II (CaMKII plays an essential role in LTP induction, but since it has the capacity to remain persistently activated even after the decay of external stimuli it has been proposed that it can also be necessary for LTP maintenance and therefore for memory persistence. It has been shown that basolateral amygdaloid nucleus (Bla stimulation induces long-term potentiation (LTP in the insular cortex (IC, a neocortical region implicated in the acquisition and retention of conditioned taste aversion (CTA. Our previous studies have demonstrated that induction of LTP in the Bla-IC pathway before CTA training increased the retention of this task. Although it is known that IC-LTP induction and CTA consolidation share similar molecular mechanisms, little is known about the molecular actors that underlie their maintenance. The purpose of the present study was to evaluate the role of CaMKII in the maintenance of in vivo Bla-IC LTP as well as in the persistence of CTA long-term memory (LTM. Our results show that acute microinfusion of myr-CaMKIINtide, a selective inhibitor of CaMKII, in the IC of adult rats during the late-phase of in vivo Bla-IC LTP blocked its maintenance. Moreover, the intracortical inhibition of CaMKII 24 h after CTA acquisition impairs CTA-LTM persistence. Together these results indicate that CaMKII is a central key component for the maintenance of neocortical synaptic plasticity as well as for persistence of CTA-LTM.

Hippocampal subfield and medial temporal cortical persistent activity during working memory reflects ongoing encoding

Directory of Open Access Journals (Sweden)

Rachel K Nauer

2015-03-01

Full Text Available Previous neuroimaging studies support a role for the medial temporal lobes (MTL in maintaining novel stimuli over brief working memory (WM delays, and suggest delay period activity predicts subsequent memory. Additionally, slice recording studies have demonstrated neuronal persistent spiking in entorhinal cortex (EC, perirhinal cortex (PrC, and hippocampus (CA1, CA3, subiculum. These data have led to computational models that suggest persistent spiking in parahippocampal regions could sustain neuronal representations of sensory information over many seconds. This mechanism may support both WM maintenance and encoding of information into long term episodic memory. The goal of the current study was to use high-resolution fMRI to elucidate the contributions of the MTL cortices and hippocampal subfields to WM maintenance as it relates to later episodic recognition memory. We scanned participants while they performed a delayed match to sample task with novel scene stimuli, and assessed their memory for these scenes post-scan. We hypothesized stimulus-driven activation that persists into the delay period—a putative correlate of persistent spiking—would predict later recognition memory. Our results suggest sample and delay period activation in the parahippocampal cortex (PHC, PrC, and subiculum (extending into DG/CA3 and CA1 was linearly related to increases in subsequent memory strength. These data extend previous neuroimaging studies that have constrained their analysis to either the sample or delay period by modeling these together as one continuous ongoing encoding process, and support computational frameworks that predict persistent activity underlies both WM and episodic encoding.

Decision making in healthy participants on the Iowa Gambling Task: new insights from an operant approach.

Science.gov (United States)

Bull, Peter N; Tippett, Lynette J; Addis, Donna Rose

2015-01-01

The Iowa Gambling Task (IGT) has contributed greatly to the study of affective decision making. However, researchers have observed high inter-study and inter-individual variability in IGT performance in healthy participants, and many are classified as impaired using standard criteria. Additionally, while decision-making deficits are often attributed to atypical sensitivity to reward and/or punishment, the IGT lacks an integrated sensitivity measure. Adopting an operant perspective, two experiments were conducted to explore these issues. In Experiment 1, 50 healthy participants completed a 200-trial version of the IGT which otherwise closely emulated Bechara et al.'s (1999) original computer task. Group data for Trials 1-100 closely replicated Bechara et al.'s original findings of high net scores and preferences for advantageous decks, suggesting that implementations that depart significantly from Bechara's standard IGT contribute to inter-study variability. During Trials 101-200, mean net scores improved significantly and the percentage of participants meeting the "impaired" criterion was halved. An operant-style stability criterion applied to individual data revealed this was likely related to individual differences in learning rate. Experiment 2 used a novel operant card task-the Auckland Card Task (ACT)-to derive quantitative estimates of sensitivity using the generalized matching law. Relative to individuals who mastered the IGT, persistent poor performers on the IGT exhibited significantly lower sensitivity to magnitudes (but not frequencies) of rewards and punishers on the ACT. Overall, our findings demonstrate the utility of operant-style analysis of IGT data and the potential of applying operant concurrent-schedule procedures to the study of human decision making.

The Importance of Team Sex Composition in Team-Training Research Employing Complex Psychomotor Tasks.

Science.gov (United States)

Jarrett, Steven M; Glaze, Ryan M; Schurig, Ira; Arthur, Winfred

2017-08-01

The relationship between team sex composition and team performance on a complex psychomotor task was examined because these types of tasks are commonly used in the lab-based teams literature. Despite well-documented sex-based differences on complex psychomotor tasks, the preponderance of studies-mainly lab based-that use these tasks makes no mention of the sex composition of teams across or within experimental conditions. A sample of 123 four-person teams with varying team sex composition learned and performed a complex psychomotor task, Steal Beasts Pro PE. Each team completed a 5-hr protocol whereby they conducted several performance missions. The results indicated significant large mean differences such that teams with larger proportions of males had higher performance scores. These findings demonstrate the potential effect of team sex composition on the validity of studies that use complex psychomotor tasks to explore and investigate team performance-related phenomena when (a) team sex composition is not a focal variable of interest and (b) it is not accounted for or controlled. Given the proclivity of complex psychomotor action-based tasks used in lab-based team studies, it is important to understand and control for the impact of team sex composition on team performance. When team sex composition is not controlled for, either methodologically or statistically, it may affect the validity of the results in teams studies using these types of tasks.

Complementary Theoretical Perspectives on Task-Based Classroom Realities

Science.gov (United States)

Jackson, Daniel O.; Burch, Alfred Rue

2017-01-01

Tasks are viewed as a principled foundation for classroom teaching, social interaction, and language development. This special issue sheds new light on how task-based classroom practices are supported by a diverse range of principles. This introduction describes current trends in classroom practice and pedagogic research in relation to task-based…

Initiation, desistance, and persistence of men's sexual coercion.

Science.gov (United States)

Hall, Gordon C Nagayama; DeGarmo, David S; Eap, Sopagna; Teten, Andra L; Sue, Stanley

2006-08-01

Patterns of sexually coercive behavior were examined among 266 Asian American and 299 European American men over 1 year. Noncoercer (n = 358), desister (n = 120), initiator (n = 39), and persistent (n = 48) sexually coercive groups were identified. The strongest predictor of sexual coercion was past sexual coercion. Persistent sexual coercers were higher than the other groups in delinquency and hostile masculinity and were nearly twice as likely to engage in laboratory sexual harassment. Loss of face attenuated self-reported sexual coercion and laboratory sexual harassment risk among Asian Americans and attenuated only laboratory sexual harassment risk among European Americans. These findings suggest that the heterogeneity of sexually coercive behavior and ethnicity are important research and clinical considerations.

Inflation persistence and flexible prices

OpenAIRE

Robert Dittmar; William T. Gavin; Finn E. Kydland

2004-01-01

If the central bank follows an interest rate rule, then inflation is likely to be persistence, even when prices are fully flexible. Any shock, whether persistent or not, may lead to inflation persistence. In equilibrium, the dynamics of inflation are determined by the evolution of the spread between the real interest rate and the central bank’s target. Inflation persistence in U.S. data can be characterized by a vector autocorrelation function relating inflation and deviations of output from ...

The long-term persistence of phytoplankton resting stages in aquatic "seed banks"

DEFF Research Database (Denmark)

Ellegaard, Marianne; Ribeiro, Sofia

2018-01-01

to terrestrial seed beds of vascular plants, but are much less studied. It is therefore timely to review the phenomenon of long-term persistence of aquatic resting stages in sediment seed banks. Herein we compare function, morphology and physiology of phytoplankton resting stages to factors central...... for persistence of terrestrial seeds. We review the types of resting stages found in different groups of phytoplankton and focus on the groups for which long-term (multi-decadal) persistence has been shown: dinoflagellates, diatoms, green algae and cyanobacteria. We discuss the metabolism of long-term dormancy......In the past decade, research on long-term persistence of phytoplankton resting stages has intensified. Simultaneously, insight into life-cycle variability in the diverse groups of phytoplankton has also increased. Aquatic 'seed banks' have tremendous significance and show many interesting parallels...

Efficient multitasking: parallel versus serial processing of multiple tasks.

Science.gov (United States)

Fischer, Rico; Plessow, Franziska

2015-01-01

In the context of performance optimizations in multitasking, a central debate has unfolded in multitasking research around whether cognitive processes related to different tasks proceed only sequentially (one at a time), or can operate in parallel (simultaneously). This review features a discussion of theoretical considerations and empirical evidence regarding parallel versus serial task processing in multitasking. In addition, we highlight how methodological differences and theoretical conceptions determine the extent to which parallel processing in multitasking can be detected, to guide their employment in future research. Parallel and serial processing of multiple tasks are not mutually exclusive. Therefore, questions focusing exclusively on either task-processing mode are too simplified. We review empirical evidence and demonstrate that shifting between more parallel and more serial task processing critically depends on the conditions under which multiple tasks are performed. We conclude that efficient multitasking is reflected by the ability of individuals to adjust multitasking performance to environmental demands by flexibly shifting between different processing strategies of multiple task-component scheduling.

San Joaquin River Up-Stream DO TMDL Project Task 4: MonitoringStudy Interim Task Report #3

Energy Technology Data Exchange (ETDEWEB)

Stringfellow, William; Borglin, Sharon; Dahlgren, Randy; Hanlon,Jeremy; Graham, Justin; Burks, Remie; Hutchinson, Kathleen

2007-03-30

The purpose of the Dissolved Oxygen Total Maximum Daily LoadProject (DO TMDLProject) is to provide a comprehensive understanding ofthe sources and fate of oxygen consuming materials in the San JoaquinRiver (SJR) watershed between Channel Point and Lander Avenue (upstreamSJR). When completed, this study will provide the stakeholders anunderstanding of the baseline conditions of the basin, provide input foran allocation decision, and provide the stakeholders with a tool formeasuring the impact of any waterquality management program that may beimplemented as part of the DO TMDL process. Previous studies haveidentified algal biomass as the most significant oxygen-demandingsubstance in the DO TMDL Project study-area between of Channel Point andLander Ave onthe SJR. Other oxygen-demanding substances found in theupstream SJR include ammonia and organic carbon from sources other thanalgae. The DO TMDL Project study-area contains municipalities, dairies,wetlands, cattle ranching, irrigated agriculture, and industries thatcould potentially contribute biochemical oxygen demand (BOD) to the SJR.This study is designed to discriminate between algal BOD and othersources of BOD throughout the entire upstream SJR watershed. Algalbiomass is not a conserved substance, but grows and decays in the SJR;hence, characterization of oxygen-demanding substances in the SJR isinherently complicated and requires an integrated effort of extensivemonitoring, scientific study, and modeling. In order to achieve projectobjectives, project activities were divided into a number of Tasks withspecific goals and objectives. In this report, we present the results ofmonitoring and research conducted under Task 4 of the DO TMDL Project.The major objective of Task 4 is to collect sufficient hydrologic (flow)and water quality (WQ) data to characterize the loading of algae, otheroxygen-demanding materials, and nutrients fromindividual tributaries andsub-watersheds of the upstream SJR between Mossdale and

Physical trust-based persistent authentication

DEFF Research Database (Denmark)

Fujita, Masahiro; Jensen, Christian D.; Arimura, Shiori

2015-01-01

propose a new type of persistent authentication, called Persistent Authentication Based On physical Trust (PABOT). PABOT uses a context of “physical trust relationship” that is built by visual contact between users, and thus can offer a persistent authentication mechanism with better usability and higher...

Preferential processing of task-irrelevant beloved-related information and task performance: Two event-related potential studies.

Science.gov (United States)

Langeslag, Sandra J E; van Strien, Jan W

2017-09-18

People who are in love have better attention for beloved-related information, but report having trouble focusing on other tasks, such as (home)work. So, romantic love can both improve and hurt cognition. Emotional information is preferentially processed, which improves task performance when the information is task-relevant, but hurts task performance when it is task-irrelevant. Because beloved-related information is highly emotional, the effects of romantic love on cognition may resemble these effects of emotion on cognition. We examined whether beloved-related information is preferentially processed even when it is task-irrelevant and whether this hurts task performance. In two event-related potential studies, participants who had recently fallen in love performed a visuospatial short-term memory task. Task-irrelevant beloved, friend, and stranger faces were presented during maintenance (Study 1), or encoding (Study 2). The Early Posterior Negativity (EPN) reflecting early automatic attentional capturing and the Late Positive Potential (LPP) reflecting sustained motivated attention were largest for beloved pictures. Thus, beloved pictures are preferentially processed even when they are task-irrelevant. Task performance and reaction times did not differ between beloved, friend, and stranger conditions. Nevertheless, self-reported obsessive thinking about the beloved tended to correlate negatively with task performance, and positively with reaction times, across conditions. So, although task-irrelevant beloved-related information does not impact task performance, more obsessive thinking about the beloved might relate to poorer and slower overall task performance. More research is needed to clarify why people experience trouble focusing on beloved-unrelated tasks and how this negative effect of love on cognition could be reduced. Copyright © 2017 Elsevier Ltd. All rights reserved.

Task-related modulations of BOLD low-frequency fluctuations within the default mode network

Science.gov (United States)

Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Eid Assan, Ibrahim; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico

2017-07-01

Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33±6 years, 8F/12M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the steady-state execution of a sustained working memory n-back task. We found that the steady state execution of such a task impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to steady-state task execution, can contribute to a better understanding of how brain networks rearrange themselves in response of a task.

Three tasks for mediatization research

DEFF Research Database (Denmark)

Ekstrøm, Mats; Fornäs, Johan; Jansson, André

2016-01-01

Based on the interdisciplinary experience of a Swedish research committee, this article discusses critical conceptual issues raised by the current debate on mediatization – a concept that holds great potential to constitute a space for synthesized understandings of media-related social transforma......Based on the interdisciplinary experience of a Swedish research committee, this article discusses critical conceptual issues raised by the current debate on mediatization – a concept that holds great potential to constitute a space for synthesized understandings of media-related social...... that mediatization researchers have sometimes formulated too grand claims as to mediatization’s status as a unitary approach, a meta-theory or a paradigm. Such claims have led to problematic confusions around the concept and should be abandoned in favour of a more open agenda. In line with such a call for openness...

Advantages and disadvantages of intraoperative language tasks in awake surgery: a three-task approach for prefrontal tumors.

Science.gov (United States)

Rofes, A; Spena, G; Miozzo, A; Fontanella, M M; Miceli, G

2015-12-01

Multidisciplinary efforts are being made to provide surgical teams with sensitive and specific tasks for language mapping in awake surgery. Researchers and clinicians have elaborated different tasks over time. A fair amount of work has been directed to study the neurofunctional correlates of some of these tasks, and there is recent interest in their standardization. However, little discussion exists on the advantages and disadvantages that each task poses from the perspective of the cognitive neuroscience of language. Such an approach may be a relevant step to assess task validity, to avoid using tasks that tap onto similar processes, and to provide patients with a surgical treatment that ensures maximal tumor resection while avoiding postoperative language deficits. An understanding of the language components that each task entails may also be relevant to improve the current assessments and the ways in which tasks are administered, and to disentangle neurofunctional questions. We reviewed 17 language mapping tasks that have been used in awake surgery. Overt production tasks have been a preferred choice over comprehension tasks. Tasks tapping lexico-semantic processes, particularly object-naming, maintain their role as gold standards. Automated speech tasks are used to detect speech errors and to set the amplitude of the stimulator. Comprehension tasks, reading and writing tasks, and tasks that assess grammatical aspects of language may be regularly administered in the near future. We provide examples of a three-task approach we are administering to patients with prefrontal lesions. We believe that future advances in this area are contingent upon reviewing gold standards and introducing new assessment tools.

Gram-positive bacteria persisting in the food production environment

DEFF Research Database (Denmark)

Knøchel, Susanne; Harmsen, Morten; Knudsen, Bettina

2008-01-01

Many gram-positive bacteria are able to form aggregates or biofilms and resist external stress factors and some gram-positive pathogenic bacteria such as Listeria monocytogenes and Bacillus cereus may persist in the food production environment for extended periods. Most research has focussed...

Interference between a fast-paced spatial puzzle task and verbal memory demands.

Science.gov (United States)

Epling, Samantha L; Blakely, Megan J; Russell, Paul N; Helton, William S

2017-06-01

Research continues to provide evidence that people are poor multi-taskers. Cognitive resource theory is a common explanation for the inability to efficiently perform multiple tasks at the same time. This theory proposes that one's limited supply of cognitive resources can be utilized faster than it is replenished, which results in a performance decline, particularly when these limited resources must be allocated among multiple tasks. Researchers have proposed both domain-specific, for example, spatial versus verbal processing resources, and domain general cognitive resources. In the present research, we investigated whether a spatial puzzle task performed simultaneously with a verbal recall task would impair performance in either task or both tasks, compared to performance on the tasks individually. As hypothesized, a reduction in word recall was found when dual-tasking, though performance on the puzzle task did not significantly differ between the single- and dual-task conditions. This is consistent, in part, with both a general resource theory and a Multiple Resource Theory, but further work is required to better understand the cognitive processing system. The employment of the recall task in the dual-task paradigm with a variety of secondary tasks will help to continue mapping out the specificity (or lack thereof) of cognitive resources utilized in various mental and physical tasks.

Resetting the bar: Establishing baselines for persistent contaminants after Hurricane Sandy in the coastal environments of New Jersey and New York, USA

Science.gov (United States)

Reilly, Timothy J.; Focazio, Michael J.; Simmons, Dale L.

2016-01-01

In the immediate aftermath of natural disasters, public health officials and other first responders engage in many activities to protect the public and ecosystems in the affected area. These activities include critical tasks designed to minimize adverse consequences resulting from chemical and microbial contaminant exposures, such as acute disease incidence and transmission. However, once these urgent priorities have been met and situations requiring immediate attention have been stabilized, questions regarding the potential longer term threats to humans and ecosystems associated with persistent contaminant exposures remain. Research conducted to address these questions is frequently challenged by the lack of available baseline contaminant information collected before the event for comparison and perspective. In addition, deployments of field crews and collection of environmental samples typically occur days, weeks, or months after the event. Consequently, during and in the aftermath of disasters, public health agencies commonly advise the public to disinfect water, avoid contact with disturbed infrastructure (such as sewer lines), and (or) refrain from use of recreational waters, with the general focus on acute health threats; however, the persisting effects of such releases on local recreational waters, fisheries, and other estuarine habitats are often undetermined.

Persistence of Gender Related-Effects on Visuo-Spatial and Verbal Working Memory in Right Brain-Damaged Patients.

Science.gov (United States)

Piccardi, Laura; Matano, Alessandro; D'Antuono, Giovanni; Marin, Dario; Ciurli, Paola; Incoccia, Chiara; Verde, Paola; Guariglia, Paola

2016-01-01

The aim of the present study was to verify if gender differences in verbal and visuo-spatial working memory would persist following right cerebral lesions. To pursue our aim we investigated a large sample (n. 346) of right brain-damaged patients and healthy participants (n. 272) for the presence of gender effects in performing Corsi and Digit Test. We also assessed a subgroup of patients (n. 109) for the nature (active vs. passive) of working memory tasks. We tested working memory (WM) administering the Corsi Test (CBT) and the Digit Span (DS) using two different versions: forward (fCBT and fDS), subjects were required to repeat stimuli in the same order that they were presented; and backward (bCBT and bDS), subjects were required to repeat stimuli in the opposite order of presentation. In this way, passive storage and active processing of working memory were assessed. Our results showed the persistence of gender-related effects in spite of the presence of right brain lesions. We found that men outperformed women both in CBT and DS, regardless of active and passive processing of verbal and visuo-spatial stimuli. The presence of visuo-spatial disorders (i.e., hemineglect) can affect the performance on Corsi Test. In our sample, men and women were equally affected by hemineglect, therefore it did not mask the gender effect. Generally speaking, the persistence of the men's superiority in visuo-spatial tasks may be interpreted as a protective factor, at least for men, within other life factors such as level of education or kind of profession before retirement.

Clinical characteristics of persistent frequent attenders in primary care: case–control study

OpenAIRE

Patel, Shireen; Kai, Joe; Atha, Christopher; Avery, Anthony; Guo, Boliang; James, Marilyn; Malins, Samuel; Sampson, Christopher James; Stubley, Michelle; Morriss, Richard K.

2015-01-01

Background. Most frequent attendance in primary care is temporary, but persistent frequent attendance is expensive and may be suitable for psychological intervention. To plan appropriate intervention and service delivery, there is a need for research involving standardized psychiatric interviews with assessment of physical health and health status.\\ud \\ud Objective. To compare the mental and physical health characteristics and health status of persistent frequent attenders (FAs) in primary ca...

Online Persistence in Higher Education Web-Supported Courses

Science.gov (United States)

Hershkovitz, Arnon; Nachmias, Rafi

2011-01-01

This research consists of an empirical study of online persistence in Web-supported courses in higher education, using Data Mining techniques. Log files of 58 Moodle websites accompanying Tel Aviv University courses were drawn, recording the activity of 1189 students in 1897 course enrollments during the academic year 2008/9, and were analyzed…

Teachers’ teaching practices and beliefs regarding context-based tasks and their relation with students’ difficulties in solving these tasks

NARCIS (Netherlands)

Wijaya, Ariyadi; Van den Heuvel-Panhuizen, M.; Doorman, Michiel

2015-01-01

In this study, we investigated teachers’ teaching practices and their underlying beliefs regarding context-based tasks to find a possible explanation for students’ difficulties with these tasks. The research started by surveying 27 Junior High School teachers from seven schools in Indonesia through

Intersectionality and HIV/AIDS. Towards Understanding the Persistence of Educational Gender Inequality in Rural Uganda

NARCIS (Netherlands)

Kakuru, D.M.; Burg, van der Margreet

2008-01-01

Gender inequalities have persisted in Uganda¿s primary education regardless of specific interventions put in place to eliminate them. These include the implementation of Universal Primary Education in 1997. Research was carried out to understand the reasons for the persistence of these inequalities.

The IGSN Experience: Successes and Challenges of Implementing Persistent Identifiers for Samples

Science.gov (United States)

Lehnert, Kerstin; Arko, Robert

2016-04-01

Physical samples collected and studied in the Earth sciences represent both a research resource and a research product in the Earth Sciences. As such they need to be properly managed, curated, documented, and cited to ensure re-usability and utility for future science, reproducibility of the data generated by their study, and credit for funding agencies and researchers who invested substantial resources and intellectual effort into their collection and curation. Use of persistent and unique identifiers and deposition of metadata in a persistent registry are therefore as important for physical samples as they are for digital data. The International Geo Sample Number (IGSN) is a persistent, globally unique identifier. Its adoption by individual investigators, repository curators, publishers, and data managers is rapidly growing world-wide. This presentation will provide an analysis of the development and implementation path of the IGSN and relevant insights and experiences gained along its way. Development of the IGSN started in 2004 as part of a US NSF-funded project to establish a registry for sample metadata, the System for Earth Sample Registration (SESAR). The initial system provided a centralized solution for users to submit information about their samples and obtain IGSNs and bar codes. Challenges encountered during this initial phase related to defining the scope of the registry, granularity of registered objects, responsibilities of relevant actors, and workflows, and designing the registry's metadata schema, its user interfaces, and the identifier itself, including its syntax. The most challenging task though was to make the IGSN an integral part of personal and institutional sample management, digital management of sample-based data, and data publication on a global scale. Besides convincing individual researchers, curators, editors and publishers, as well as data managers in US and non-US academia, state and federal agencies, the PIs of the SESAR project

Persistent homology of complex networks

International Nuclear Information System (INIS)

Horak, Danijela; Maletić, Slobodan; Rajković, Milan

2009-01-01

Long-lived topological features are distinguished from short-lived ones (considered as topological noise) in simplicial complexes constructed from complex networks. A new topological invariant, persistent homology, is determined and presented as a parameterized version of a Betti number. Complex networks with distinct degree distributions exhibit distinct persistent topological features. Persistent topological attributes, shown to be related to the robust quality of networks, also reflect the deficiency in certain connectivity properties of networks. Random networks, networks with exponential connectivity distribution and scale-free networks were considered for homological persistency analysis

Decision paths in complex tasks

Science.gov (United States)

Galanter, Eugene

1991-01-01

Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

Incentive Processing in Persistent Disruptive Behavior and Psychopathic Traits: A Functional Magnetic Resonance Imaging Study in Adolescents.

Science.gov (United States)

Cohn, Moran D; Veltman, Dick J; Pape, Louise E; van Lith, Koen; Vermeiren, Robert R J M; van den Brink, Wim; Doreleijers, Theo A H; Popma, Arne

2015-11-01

Children with early-onset disruptive behavior disorder (DBD), especially those with callous-unemotional traits, are at risk of developing persistent and severe adult antisocial behavior. One possible underlying mechanism for persistence is deficient reward and loss sensitivity, i.e., deficient incentive processing. However, little is known about the relation between deficient incentive processing and persistence of antisocial behavior into adulthood or its relation with callous-unemotional and other psychopathic traits. In this study, we investigate the relationship between the neural correlates of incentive processing and both DBD persistence and psychopathic traits. In a sample of 128 adolescents (mean age 17.7) with a history of criminal offending before age 12, functional magnetic resonance imaging was performed during a monetary incentive delay task designed to assess neural responses during incentive processing. Neural activation during incentive processing was then associated with DBD persistence and psychopathic traits, measured with the Youth Psychopathic Traits Inventory. Compared with both healthy control subjects and youths who had desisted from DBD, persistent DBD subjects showed lower neural responses in the ventral striatum during reward outcomes and higher neural responses in the amygdala during loss outcomes. Callous-unemotional traits were related to lower neural responses in the amygdala during reward outcomes, while other psychopathic traits were not related to incentive processing. In the current study, aberrant incentive processing is related to persistence of childhood antisocial behavior into late adolescence and to callous-unemotional traits. This mechanism may underlie treatment resistance in a subgroup of antisocial youth and provide a target for intervention. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Persistent Factors Facilitating Excellence in Research Environments

Science.gov (United States)

Kalpazidou Schmidt, Evanthia; Graversen, Ebbe Krogh

2018-01-01

The study presented here identifies robust and time-invariant features that characterise dynamic and innovative research environments. It takes as its point of departure the results of an empirical study conducted in 2002 which identified the common characteristics of 15 dynamic and innovative public research environments, and focusses on their…

Persistent Identifiers, Discoverability and Open Science (Communication)

Science.gov (United States)

Murphy, Fiona; Lehnert, Kerstin; Hanson, Brooks

2016-04-01

Early in 2016, the American Geophysical Union announced it was incorporating ORCIDs into its submission workflows. This was accompanied by a strong statement supporting the use of other persistent identifiers - such as IGSNs, and the CrossRef open registry 'funding data'. This was partly in response to funders' desire to track and manage their outputs. However the more compelling argument, and the reason why the AGU has also signed up to the Center for Open Science's Transparency and Openness Promotion (TOP) Guidelines (http://cos.io/top), is that ultimately science and scientists will be the richer for these initiatives due to increased opportunities for interoperability, reproduceability and accreditation. The AGU has appealed to the wider community to engage with these initiatives, recognising that - unlike the introduction of Digital Object Identifiers (DOIs) for articles by CrossRef - full, enriched use of persistent identifiers throughout the scientific process requires buy-in from a range of scholarly communications stakeholders. At the same time, across the general research landscape, initiatives such as Project CRediT (contributor roles taxonomy), Publons (reviewer acknowledgements) and the forthcoming CrossRef DOI Event Tracker are contributing to our understanding and accreditation of contributions and impact. More specifically for earth science and scientists, the cross-functional Coalition for Publishing Data in the Earth and Space Sciences (COPDESS) was formed in October 2014 and is working to 'provide an organizational framework for Earth and space science publishers and data facilities to jointly implement and promote common policies and procedures for the publication and citation of data across Earth Science journals'. Clearly, the judicious integration of standards, registries and persistent identifiers such as ORCIDs and International Geo Sample Numbers (IGSNs) to the research and research output processes is key to the success of this venture

"Whether I like it or not, it's important": Implicit importance of means predicts self-regulatory persistence and success.

Science.gov (United States)

Critcher, Clayton R; Ferguson, Melissa J

2016-06-01

To effectively self-regulate, people must persevere on tasks that they deem important, regardless of whether those tasks are enjoyable. Building on past work that has noted the fundamental role of implicit cognition in guiding effective self-regulation, the present paper tests whether an implicit association between goal means and importance predicts self-regulatory persistence and success. Implicit importance predicted markers of effective self-regulation-better grades, more studying and exercise, and stronger standardized testing performance-over and above, and often better than, explicit beliefs about the importance of that self-regulation, as well as implicit evaluations of those means. In particular, those for whom tasks were fairly taxing to complete (i.e., those for whom this self-regulation required effortful self-control) were those who most benefitted from the implicit association between means and importance. Moreover, when participants were reminded of recent self-regulatory failure that they believed could be overcome through hard work, implicit importance toward the means increased as if to prepare them to achieve self-regulatory persistence. A final study sought to reconcile the present findings with previous work showing the key role that implicit evaluations play in effective self-regulation. We reasoned that means are important precisely because they are associated with valued end-states. Consistent with this account, implicit evaluations of end-states predicted the implicit importance of means, which in turn predicted effective self-regulation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Assessing inflation persistence: micro evidence on an inflation targeting economy

Czech Academy of Sciences Publication Activity Database

Babecký, Jan; Coricelli, F.; Horváth, R.

-, č. 353 (2008), s. 1-37 ISSN 1211-3298 Institutional research plan: CEZ:AV0Z70850503 Keywords : inflation dynamics * persistence * inflation targeting Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp353.pdf

Task-Modality and L1 Use in EFL Oral Interaction

Science.gov (United States)

Azkarai, Agurtzane; del Pilar García Mayo, María

2015-01-01

This study examines whether task-modality (speaking vs. speaking+writing) influences first language (L1) use in task-based English as a foreign language (EFL) learner-learner interaction. Research on the topic has shown that different task-modality triggers different learning opportunities with collaborative speaking tasks drawing learners'…

Persistent luminescence nanothermometers

Science.gov (United States)

Martín Rodríguez, Emma; López-Peña, Gabriel; Montes, Eduardo; Lifante, Ginés; García Solé, José; Jaque, Daniel; Diaz-Torres, Luis Armando; Salas, Pedro

2017-08-01

Persistent phosphorescence nanoparticles emitting in the red and near-infrared spectral regions are strongly demanded as contrast nanoprobes for autofluorescence free bioimaging and biosensing. In this work, we have developed Sr4Al14O25:Eu2+, Cr3+, Nd3+ nanopowders that produce persistent red phosphorescence peaking at 694 nm generated by Cr3+ ions. This emission displays temperature sensitivity in the physiological temperature range (20-60 °C), which makes these nanoparticles potentially useful as fluorescence (contactless) nanothermometers operating without requiring optical excitation. Nd3+ ions, which act as shallow electron traps for the red Cr3+ persistent emission, also display infrared emission bands, extending the fluorescence imaging capability to the second biological window. This unique combination of properties makes these nanoparticles multifunctional luminescent probes with great potential applications in nanomedicine.

Locus of Control, Self-Efficacy, and Task Value as Predictors of Learning Outcome in an Online University Context

Science.gov (United States)

Joo, Young Ju; Lim, Kyu Yon; Kim, Jiyeon

2013-01-01

This study investigates the predictors of learner satisfaction, achievement and persistence in an online university located in South Korea. The specific predictors were learners' locus of control, self-efficacy, and task value, and the mediating effects of learner satisfaction and achievement were also tested. Structural equation modeling (SEM)…

Asymmetrical learning between a tactile and visual serial RT task

NARCIS (Netherlands)

Abrahamse, E.L.; van der Lubbe, Robert Henricus Johannes; Verwey, Willem B.

2007-01-01

According to many researchers, implicit learning in the serial reaction-time task is predominantly motor based and therefore should be independent of stimulus modality. Previous research on the task, however, has focused almost completely on the visual domain. Here we investigated sequence learning

Interleaved Practice in Multi-Dimensional Learning Tasks: Which Dimension Should We Interleave?

Science.gov (United States)

Rau, Martina A.; Aleven, Vincent; Rummel, Nikol

2013-01-01

Research shows that multiple representations can enhance student learning. Many curricula use multiple representations across multiple task types. The temporal sequence of representations and task types is likely to impact student learning. Research on contextual interference shows that interleaving learning tasks leads to better learning results…

Saffold Virus Type 3 (SAFV-3) Persists in HeLa Cells

Science.gov (United States)

Himeda, Toshiki; Hosomi, Takushi; Okuwa, Takako; Muraki, Yasushi; Ohara, Yoshiro

2013-01-01

Saffold virus (SAFV) was identified as a human cardiovirus in 2007. Although several epidemiological studies have been reported, they have failed to provide a clear picture of the relationship between SAFV and human diseases. SAFV genotype 3 has been isolated from the cerebrospinal fluid specimen of patient with aseptic meningitis. This finding is of interest since Theiler’s murine encephalomyelitis virus (TMEV), which is the closely related virus, is known to cause a multiple sclerosis-like syndrome in mice. TMEV persistently infects in mouse macrophage cells in vivo and in vitro, and the viral persistence is essential in TMEV-induced demyelinating disease. The precise mechanism(s) of SAFV infection still remain unclear. In order to clarify the SAFV pathogenicity, in the present study, we studied the possibilities of the in vitro persistent infection of SAFV. The two distinct phenotypes of HeLa cells, HeLa-N and HeLa-R, were identified. In these cells, the type of SAFV-3 infection was clearly different. HeLa-N cells were lyticly infected with SAFV-3 and the host suitable for the efficient growth. On the other hand, HeLa-R cells were persistently infected with SAFV-3. In addition, the SAFV persistence in HeLa-R cells is independent of type I IFN response of host cells although the TMEV persistence in mouse macrophage cells depends on the response. Furthermore, it was suggested that SAFV persistence may be influenced by the expression of receptor(s) for SAFV infection on the host cells. The present findings on SAFV persistence will provide the important information to encourage the research of SAFV pathogenicity. PMID:23308162

All Cues Are Not Created Equal: Obtaining Attitude Persistence under Low-Involvement Conditions.

OpenAIRE

Sengupta, Jaideep; Goodstein, Ronald C; Boninger, David S

1997-01-01

Attitude persistence research in consumer behavior has been predominantly associated with high- rather than low-involvement processing. Advertising, however, is most often processed as a low-involvement communication. The authors predict that different low-involvement cues lead to different degrees of attitude persistence. Consistent with this prediction, they find that under low-involvement conditions, when both related and unrelated peripheral cues evoke similar initial attitudes, only when...

An Exploratory Study of Teaching Tasks in English as a Foreign Language Education. Research Report. ETS RR-17-56

Science.gov (United States)

Turkan, Sultan; Timpe-Laughlin, Veronika; Papageorgiou, Spiros

2017-01-01

Due to rising demand for qualified teachers of English as a foreign language (EFL), interest in issues pertaining to the language proficiency of these teachers has increased. However, research focusing on the teaching tasks that EFL teachers engage in for the purposes of EFL instruction is scant. The present study aims to address this gap in the…

Social Network Analysis as an Analytic Tool for Task Group Research: A Case Study of an Interdisciplinary Community of Practice

Science.gov (United States)

Lockhart, Naorah C.

2017-01-01

Group counselors commonly collaborate in interdisciplinary settings in health care, substance abuse, and juvenile justice. Social network analysis is a methodology rarely used in counseling research yet has potential to examine task group dynamics in new ways. This case study explores the scholarly relationships among 36 members of an…

Are women better than men at multi-tasking?

OpenAIRE

Stoet, Gijsbert; O’Connor, Daryl B.; Conner, Mark; Laws, Keith R.

2013-01-01

Background: There seems to be a common belief that women are better in multi-tasking than men, but there is practically no scientific research on this topic. Here, we tested whether women have better multi-tasking skills than men.\\ensuremath\\ensuremath Methods: In Experiment 1, we compared performance of 120 women and 120 men in a computer-based task-switching paradigm. In Experiment 2, we compared a different group of 47 women and 47 men on "paper-and-pencil" multi-tasking tests.\\ensuremath\\...

Is bacterial persistence a social trait?

Directory of Open Access Journals (Sweden)

Andy Gardner

Full Text Available The ability of bacteria to evolve resistance to antibiotics has been much reported in recent years. It is less well-known that within populations of bacteria there are cells which are resistant due to a non-inherited phenotypic switch to a slow-growing state. Although such 'persister' cells are receiving increasing attention, the evolutionary forces involved have been relatively ignored. Persistence has a direct benefit to cells because it allows survival during catastrophes-a form of bet-hedging. However, persistence can also provide an indirect benefit to other individuals, because the reduced growth rate can reduce competition for limiting resources. This raises the possibility that persistence is a social trait, which can be influenced by kin selection. We develop a theoretical model to investigate the social consequences of persistence. We predict that selection for persistence is increased when: (a cells are related (e.g. a single, clonal lineage; and (b resources are scarce. Our model allows us to predict how the level of persistence should vary with time, across populations, in response to intervention strategies and the level of competition. More generally, our results clarify the links between persistence and other bet-hedging or social behaviours.

Inflation persistence : euro area and new EU member states

Czech Academy of Sciences Publication Activity Database

Franta, Michal; Saxa, Branislav; Šmídková, K.

-, č. 810 (2007), s. 1-39 ISSN 1725-2806 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : inflation persistence * new EU member states * time varying mean Subject RIV: AH - Economics http://www.ecb.int/pub/pdf/scpwps/ecbwp810.pdf

Logic of Leadership Research: A Reflective Review of Geeks & Geezers by Bennis and Thomas

Directory of Open Access Journals (Sweden)

D. P. Dash

2005-01-01

Full Text Available [First two paragraphs] Leadership has turned out to be one of those topics, which persistently slip out of scientific hands. The field of leadership research should be of interest to researchers in various other disciplines, because it serves as a source of examples of many common difficulties faced by researchers in general. These relate to difficulties in defining a research task, specifying quality criteria, choosing methods, ensuring that the research programme remains progressive (the criterion is from Lakatos, see Science and Pseudoscience, 2004; Worrall & Currie, 1978, etc. The book by well-known leadership researchers, Bennis and Thomas, gives us an occasion to critically appreciate the practice of leadership research so far and assess the book’s potential contribution. This will be done by first outlining the developments in leadership research since the 1930s. It will be shown that although the book’s focus is interestingly different, it does not go so far as to reframe the logic of research in the field.

Microevaluating Learners' Task-Specific Motivation in a Task-Based Business Spanish Course

Science.gov (United States)

Torres, Julio; Serafini, Ellen J.

2016-01-01

Scholars of task-based language teaching (TBLT) advocate for the identification of learners' communicative needs to inform syllabus design, particularly in language for specific purposes contexts (e.g., Long 2015). However, little research has applied TBLT principles in designing Spanish for specific purposes curricula. Moreover, despite the…

Middle School Teachers' Views and Approaches to Implement Mathematical Tasks

Science.gov (United States)

Yesildere-Imre, Sibel; Basturk-Sahin, Burcu Nur

2016-01-01

This research examines middle school mathematics teachers' views regarding implementation of mathematical tasks and their enactments. We compare their views on tasks and their implementation, and determine the causes of difference between the two using qualitative research methods. We interview sixteen middle school mathematics teachers based on…

Reading Fluency and Speech Perception Speed of Beginning Readers with Persistent Reading Problems: The Perception of Initial Stop Consonants and Consonant Clusters

Science.gov (United States)

Snellings, Patrick; van der Leij, Aryan; Blok, Henk; de Jong, Peter F.

2010-01-01

This study investigated the role of speech perception accuracy and speed in fluent word decoding of reading disabled (RD) children. A same-different phoneme discrimination task with natural speech tested the perception of single consonants and consonant clusters by young but persistent RD children. RD children were slower than chronological age…

How different types of participant payments alter task performance

Directory of Open Access Journals (Sweden)

Gary L. Brase

2009-08-01

Full Text Available Researchers typically use incentives (such as money or course credit in order to obtain participants who engage in the specific behaviors of interest to the researcher. There is, however, little understanding or agreement on the effects of different types and levels of incentives used. Some results in the domain of statistical reasoning suggest that performance differences --- previously deemed theoretically important --- may actually be due to differences in incentive types across studies. 704 participants completed one of five variants of a statistical reasoning task, for which they received either course credit, flat fee payment, or performance-based payment incentives. Successful task completion was more frequent with performance-based incentives than with either of the other incentive types. Performance on moderately difficult tasks (compared to very easy and very hard tasks was most sensitive to incentives. These results can help resolve existing debates about inconsistent findings, guide more accurate comparisons across studies, and be applied beyond research settings.

Higher persistence with valsartan compared with enalapril in daily practice

Directory of Open Access Journals (Sweden)

Satu J Siiskonen

2008-01-01

Full Text Available Satu J Siiskonen1, Nancy S Breekveldt-Postma1, Gábor Vincze2, Zeba M Khan3, Joëlle A Erkens1, Ron MC Herings11PHARMO Institute for Drug Outcomes Research, Utrecht, The Netherlands; 2Novartis Pharma AG, Basel, Switzerland; 3Novartis Pharmaceuticals Corporation, East Hanover, NJ, USAObjective: To compare persistence with valsartan and enalapril in daily practice.Methods: The PHARMO Record Linkage System includes various data registries including drug dispensing and hospitalizations for ≥2 million subjects in the Netherlands. Patients newly treated with valsartan or enalapril in the period of 1999–2002 were selected. Persistence was calculated by summing up the number of days of continuous treatment. Patients who remained on therapy with valsartan or enalapril for 12 or 24 months were defined as persistent at 1 or 2 years, respectively.Results: 3364 patients received valsartan and 9103 patients received enalapril. About 62% of patients treated with valsartan and 55% of patients treated with enalapril remained on therapy at 12 months after the initial dispensing, while 48% of patients treated with valsartan and 43% of patients treated with enalapril were persistent at 24 months. Patients treated with valsartan were about 20% more likely to stay on treatment than patients treated with enalapril (1 year RRadj: 1.23, 95% CI: 1.16–1.32; 2 years RRadj: 1.16, 95% CI: 1.11–1.23.Conclusions: Real-life persistence is higher with valsartan than with enalapril. The results of this and other studies on persistence in daily practice should be taken into account when deciding upon drug treatment for hypertension.Keywords: persistence, antihypertensive, valsartan, enalapril, angiotensin-converting enzyme inhibitors, angiotensin-2-receptor blockers

Teachers' Teaching Practices and Beliefs Regarding Context-Based Tasks and Their Relation with Students' Difficulties in Solving These Tasks

Science.gov (United States)

Wijaya, Ariyadi; van den Heuvel-Panhuizen, Marja; Doorman, Michiel

2015-01-01

In this study, we investigated teachers' teaching practices and their underlying beliefs regarding context-based tasks to find a possible explanation for students' difficulties with these tasks. The research started by surveying 27 Junior High School teachers from seven schools in Indonesia through a written questionnaire. Then, to further examine…

Wind power forecasting: IEA Wind Task 36 & future research issues

DEFF Research Database (Denmark)

Giebel, Gregor; Cline, J.; Frank, Helmut Paul

2016-01-01

the weather prediction side and from the usage of the forecasts. The new International Energy Agency (IEA) Task on Forecasting for Wind Energy tries to organise international collaboration, among national meteorological centres with an interest and/or large projects on wind forecast improvements (NOAA, DWD...

Persistent Aerial Tracking

KAUST Repository

Mueller, Matthias

2016-04-13

In this thesis, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photo-realistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the rst evaluation of many state of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. We also present a simulator that can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV "in the field", as well as, generate synthetic but photo-realistic tracking datasets with free ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator will be made publicly available to the vision community to further research in the area of object tracking from UAVs. Additionally, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by \\'handing over the camera\\' from one UAV to another. We integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

Persistence of Gender Related-Effects on Visuo-Spatial and Verbal Working Memory in Right Brain-Damaged Patients

Science.gov (United States)

Piccardi, Laura; Matano, Alessandro; D’Antuono, Giovanni; Marin, Dario; Ciurli, Paola; Incoccia, Chiara; Verde, Paola; Guariglia, Paola

2016-01-01

The aim of the present study was to verify if gender differences in verbal and visuo-spatial working memory would persist following right cerebral lesions. To pursue our aim we investigated a large sample (n. 346) of right brain-damaged patients and healthy participants (n. 272) for the presence of gender effects in performing Corsi and Digit Test. We also assessed a subgroup of patients (n. 109) for the nature (active vs. passive) of working memory tasks. We tested working memory (WM) administering the Corsi Test (CBT) and the Digit Span (DS) using two different versions: forward (fCBT and fDS), subjects were required to repeat stimuli in the same order that they were presented; and backward (bCBT and bDS), subjects were required to repeat stimuli in the opposite order of presentation. In this way, passive storage and active processing of working memory were assessed. Our results showed the persistence of gender-related effects in spite of the presence of right brain lesions. We found that men outperformed women both in CBT and DS, regardless of active and passive processing of verbal and visuo-spatial stimuli. The presence of visuo-spatial disorders (i.e., hemineglect) can affect the performance on Corsi Test. In our sample, men and women were equally affected by hemineglect, therefore it did not mask the gender effect. Generally speaking, the persistence of the men’s superiority in visuo-spatial tasks may be interpreted as a protective factor, at least for men, within other life factors such as level of education or kind of profession before retirement. PMID:27445734

Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force-1.

Science.gov (United States)

Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

2012-01-01

Models-mathematical frameworks that facilitate estimation of the consequences of health care decisions-have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR modeling task force reported in 2003 has led to a new task force, jointly convened with the Society for Medical Decision Making, and this series of seven papers presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; dealing with uncertainty; and validating and reporting models transparently. This overview introduces the work of the task force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these papers includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making.

Identification and Analysis of Multi-tasking Product Information Search Sessions with Query Logs

Directory of Open Access Journals (Sweden)

Xiang Zhou

2016-09-01

Full Text Available Purpose: This research aims to identify product search tasks in online shopping and analyze the characteristics of consumer multi-tasking search sessions. Design/methodology/approach: The experimental dataset contains 8,949 queries of 582 users from 3,483 search sessions. A sequential comparison of the Jaccard similarity coefficient between two adjacent search queries and hierarchical clustering of queries is used to identify search tasks. Findings: (1 Users issued a similar number of queries (1.43 to 1.47 with similar lengths (7.3-7.6 characters per task in mono-tasking and multi-tasking sessions, and (2 Users spent more time on average in sessions with more tasks, but spent less time for each task when the number of tasks increased in a session. Research limitations: The task identification method that relies only on query terms does not completely reflect the complex nature of consumer shopping behavior. Practical implications: These results provide an exploratory understanding of the relationships among multiple shopping tasks, and can be useful for product recommendation and shopping task prediction. Originality/value: The originality of this research is its use of query clustering with online shopping task identification and analysis, and the analysis of product search session characteristics.

Integrated Task And Data Parallel Programming: Language Design

Science.gov (United States)

Grimshaw, Andrew S.; West, Emily A.

1998-01-01

his research investigates the combination of task and data parallel language constructs within a single programming language. There are an number of applications that exhibit properties which would be well served by such an integrated language. Examples include global climate models, aircraft design problems, and multidisciplinary design optimization problems. Our approach incorporates data parallel language constructs into an existing, object oriented, task parallel language. The language will support creation and manipulation of parallel classes and objects of both types (task parallel and data parallel). Ultimately, the language will allow data parallel and task parallel classes to be used either as building blocks or managers of parallel objects of either type, thus allowing the development of single and multi-paradigm parallel applications. 1995 Research Accomplishments In February I presented a paper at Frontiers '95 describing the design of the data parallel language subset. During the spring I wrote and defended my dissertation proposal. Since that time I have developed a runtime model for the language subset. I have begun implementing the model and hand-coding simple examples which demonstrate the language subset. I have identified an astrophysical fluid flow application which will validate the data parallel language subset. 1996 Research Agenda Milestones for the coming year include implementing a significant portion of the data parallel language subset over the Legion system. Using simple hand-coded methods, I plan to demonstrate (1) concurrent task and data parallel objects and (2) task parallel objects managing both task and data parallel objects. My next steps will focus on constructing a compiler and implementing the fluid flow application with the language. Concurrently, I will conduct a search for a real-world application exhibiting both task and data parallelism within the same program m. Additional 1995 Activities During the fall I collaborated

A Validated Task Analysis of the Single Pilot Operations Concept

Science.gov (United States)

Wolter, Cynthia A.; Gore, Brian F.

2015-01-01

The current day flight deck operational environment consists of a two-person Captain/First Officer crew. A concept of operations (ConOps) to reduce the commercial cockpit to a single pilot from the current two pilot crew is termed Single Pilot Operations (SPO). This concept has been under study by researchers in the Flight Deck Display Research Laboratory (FDDRL) at the National Aeronautics and Space Administration's (NASA) Ames (Johnson, Comerford, Lachter, Battiste, Feary, and Mogford, 2012) and researchers from Langley Research Centers (Schutte et al., 2007). Transitioning from a two pilot crew to a single pilot crew will undoubtedly require changes in operational procedures, crew coordination, use of automation, and in how the roles and responsibilities of the flight deck and ATC are conceptualized in order to maintain the high levels of safety expected of the US National Airspace System. These modifications will affect the roles and the subsequent tasks that are required of the various operators in the NextGen environment. The current report outlines the process taken to identify and document the tasks required by the crew according to a number of operational scenarios studied by the FDDRL between the years 2012-2014. A baseline task decomposition has been refined to represent the tasks consistent with a new set of entities, tasks, roles, and responsibilities being explored by the FDDRL as the move is made towards SPO. Information from Subject Matter Expert interviews, participation in FDDRL experimental design meetings, and study observation was used to populate and refine task sets that were developed as part of the SPO task analyses. The task analysis is based upon the proposed ConOps for the third FDDRL SPO study. This experiment possessed nine different entities operating in six scenarios using a variety of SPO-related automation and procedural activities required to guide safe and efficient aircraft operations. The task analysis presents the roles and

Applications of Task-Based Learning in TESOL

Science.gov (United States)

Shehadeh, Ali, Ed.; Coombe, Christine, Ed.

2010-01-01

Why are many teachers around the world moving toward task-based learning (TBL)? This shift is based on the strong belief that TBL facilitates second language acquisition and makes second language learning and teaching more principled and effective. Based on insights gained from using tasks as research tools, this volume shows how teachers can use…

Fluctuations in work motivation: tasks do not matter!

Science.gov (United States)

Navarro, Jose; Curioso, Fernando; Gomes, Duarte; Arrieta, Carlos; Cortes, Mauricio

2013-01-01

Previous studies have shown that work motivation fluctuates considerably and in a nonlinear way over time. In the present research, we are interested in studying if the task at hand does or does not influence the presence of these fluctuations. We gathered daily registers from 69 workers during 21 consecutive working days (7036 registers) of task developed and levels of motivation, self-efficacy beliefs and instrumentalities perception. These registers were then categorized into a list of labor activities in main tasks and subtasks by means of three judges with a high level of agreement (97.47% for tasks, and 98.64% for subtasks). Taking the MSSD statistic (mean squared successive difference) of the average of motivation, self-efficacy and instrumentality, and using hierarchical regression analysis we have found that tasks (beta = .03; p = .188) and subtasks (beta = .10; p = .268) do not affect the presence of fluctuations in motivation. These results reveal instability in work motivation independently from the tasks and subtasks that the workers do. We proceed to find that fluctuations in work motivation show a fractal structure across the different tasks we do in a working day. Implications of these results to motivational theory will be discussed as well as possible explanations (e.g. the influence of affect in work motivation) and directions for future research are provided.

NASA's Big Data Task Force

Science.gov (United States)

Holmes, C. P.; Kinter, J. L.; Beebe, R. F.; Feigelson, E.; Hurlburt, N. E.; Mentzel, C.; Smith, G.; Tino, C.; Walker, R. J.

2017-12-01

Two years ago NASA established the Ad Hoc Big Data Task Force (BDTF - https://science.nasa.gov/science-committee/subcommittees/big-data-task-force), an advisory working group with the NASA Advisory Council system. The scope of the Task Force included all NASA Big Data programs, projects, missions, and activities. The Task Force focused on such topics as exploring the existing and planned evolution of NASA's science data cyber-infrastructure that supports broad access to data repositories for NASA Science Mission Directorate missions; best practices within NASA, other Federal agencies, private industry and research institutions; and Federal initiatives related to big data and data access. The BDTF has completed its two-year term and produced several recommendations plus four white papers for NASA's Science Mission Directorate. This presentation will discuss the activities and results of the TF including summaries of key points from its focused study topics. The paper serves as an introduction to the papers following in this ESSI session.

When Task Conflict Becomes Personal

Science.gov (United States)

Guenter, Hannes; van Emmerik, Hetty; Schreurs, Bert; Kuypers, Tom; van Iterson, Ad; Notelaers, Guy

2016-01-01

Although potentially beneficial, task conflict may threaten teams because it often leads to relationship conflict. Prior research has identified a set of interpersonal factors (e.g., team communication, team trust) that help attenuate this association. The purpose of this article is to provide an alternative perspective that focuses on the moderating role of performance-related factors (i.e., perceived team performance). Using social identity theory, we build a model that predicts how task conflict associates with growth in relationship conflict and how perceived team performance influences this association. We test a three-wave longitudinal model by means of random coefficient growth modeling, using data from 60 ongoing teams working in a health care organization. Results provide partial support for our hypotheses. Only when perceived team performance is low, do task conflicts relate with growth in relationship conflict. We conclude that perceived team performance seems to enable teams to uncouple task from relationship conflict. PMID:28190944

Dualities in persistent (co)homology

International Nuclear Information System (INIS)

De Silva, Vin; Morozov, Dmitriy; Vejdemo-Johansson, Mikael

2011-01-01

We consider sequences of absolute and relative homology and cohomology groups that arise naturally for a filtered cell complex. We establish algebraic relationships between their persistence modules, and show that they contain equivalent information. We explain how one can use the existing algorithm for persistent homology to process any of the four modules, and relate it to a recently introduced persistent cohomology algorithm. We present experimental evidence for the practical efficiency of the latter algorithm

Designing Task-Based Syllabus For Writing Class

Directory of Open Access Journals (Sweden)

Sundari Hanna

2018-01-01

Full Text Available Writing is viewed as the most complex skill to learn and to teach. Beside learner factors, teacher, materials and syllabus may also affect the process of learning language as foreign language. Syllabus, in general, can be defined as a set of what is taught (content and the way it is taught (procedure. This current research aims to design a task-based syllabus for writing class at university level. This study was conducted by qualitative descriptive design with 92 students and 4 lecturers as respondents. As part of research and development project in one private university in Jakarta, a developed task-based syllabus was based on need analysis and the principles of task-based language teaching. Students’ proficiency levels are fair with sentence patterns and grammar as the most difficult aspects. Academic writing is more preferable orientation with the small portions of creative writing. Then, the developed task-based syllabus has been proposed for writing class which covers the components of goal (learning outcome, course description and objectives, a set of writing tasks, features of content focus and language focus and course evaluation. The developed syllabus, then, can guide the lecturers in designing lesson plan and selecting materials for writing class.

Thoughts in flight: automation use and pilots' task-related and task-unrelated thought.

Science.gov (United States)

Casner, Stephen M; Schooler, Jonathan W

2014-05-01

The objective was to examine the relationship between cockpit automation use and task-related and task-unrelated thought among airline pilots. Studies find that cockpit automation can sometimes relieve pilots of tedious control tasks and afford them more time to think ahead. Paradoxically, automation has also been shown to lead to lesser awareness. These results prompt the question of what pilots think about while using automation. A total of 18 airline pilots flew a Boeing 747-400 simulator while we recorded which of two levels of automation they used. As they worked, pilots were verbally probed about what they were thinking. Pilots were asked to categorize their thoughts as pertaining to (a) a specific task at hand, (b) higher-level flight-related thoughts (e.g.,planning ahead), or (c) thoughts unrelated to the flight. Pilots' performance was also measured. Pilots reported a smaller percentage of task-at-hand thoughts (27% vs. 50%) and a greater percentage of higher-level flight-related thoughts (56% vs. 29%) when using the higher level of automation. However, when all was going according to plan, using either level of automation, pilots also reported a higher percentage of task-unrelated thoughts (21%) than they did when in the midst of an unsuccessful performance (7%). Task-unrelated thoughts peaked at 25% when pilots were not interacting with the automation. Although cockpit automation may provide pilots with more time to think, it may encourage pilots to reinvest only some of this mental free time in thinking flight-related thoughts. This research informs the design of human-automation systems that more meaningfully engage the human operator.

Trait Mindfulness and Cognitive Task Performance

Directory of Open Access Journals (Sweden)

Emalee J. W. Quickel

2014-11-01

Full Text Available Mindfulness meditation (MM training has been shown to have positive effects on working memory and focused attention tasks. Clarifying the construct of mindfulness is important so that mindfulness can be studied effectively in individual differences and cognition research. The current study tested whether trait mindfulness alone explains any of the variability on task performance. Five commonly used mindfulness scales, as well as six standardized and experimental attention and working memory tasks were administered to 164 participants with no meditation experience. Confirmatory factor analysis found that the common variance denoted by measures of trait mindfulness is unrelated to the common variance among tasks requiring focused attention. These results indicate that mindfulness scales may not be capturing the attentional aspects of mindfulness. Individuals who score high on mindfulness scales do not perform better on focused attention tasks than those who score lower on mindfulness scales. These results have implications for defining and operationalizing mindfulness.

Serial or overlapping processing in multitasking as individual preference: Effects of stimulus preview on task switching and concurrent dual-task performance.

Science.gov (United States)

Reissland, Jessika; Manzey, Dietrich

2016-07-01

Understanding the mechanisms and performance consequences of multitasking has long been in focus of scientific interest, but has been investigated by three research lines more or less isolated from each other. Studies in the fields of the psychological refractory period, task switching, and interruptions have scored with a high experimental control, but usually do not give participants many degrees of freedom to self-organize the processing of two concurrent tasks. Individual strategies as well as their impact on efficiency have mainly been neglected. Self-organized multitasking has been investigated in the field of human factors, but primarily with respect to overall performance without detailed investigation of how the tasks are processed. The current work attempts to link aspects of these research lines. All of them, explicitly or implicitly, provide hints about an individually preferred type of task organization, either more cautious trying to work strictly serially on only one task at a time or more daring with a focus on task interleaving and, if possible, also partially overlapping (parallel) processing. In two experiments we investigated different strategies of task organization and their impact on efficiency using a new measure of overall multitasking efficiency. Experiment 1 was based on a classical task switching paradigm with two classification tasks, but provided one group of participants with a stimulus preview of the task to switch to next, enabling at least partial overlapping processing. Indeed, this preview led to a reduction of switch costs and to an increase of dual-task efficiency, but only for a subgroup of participants. They obviously exploited the possibility of overlapping processing, while the others worked mainly serially. While task-sequence was externally guided in the first experiment, Experiment 2 extended the approach by giving the participants full freedom of task organization in concurrent performance of the same tasks. Fine

The Influence of Math Anxiety, Math Performance, Worry, and Test Anxiety on the Iowa Gambling Task and Balloon Analogue Risk Task.

Science.gov (United States)

Buelow, Melissa T; Barnhart, Wesley R

2017-01-01

Multiple studies have shown that performance on behavioral decision-making tasks, such as the Iowa Gambling Task (IGT) and Balloon Analogue Risk Task (BART), is influenced by external factors, such as mood. However, the research regarding the influence of worry is mixed, and no research has examined the effect of math or test anxiety on these tasks. The present study investigated the effects of anxiety (including math anxiety) and math performance on the IGT and BART in a sample of 137 undergraduate students. Math performance and worry were not correlated with performance on the IGT, and no variables were correlated with BART performance. Linear regressions indicated math anxiety, physiological anxiety, social concerns/stress, and test anxiety significantly predicted disadvantageous selections on the IGT during the transition from decision making under ambiguity to decision making under risk. Implications for clinical evaluation of decision making are discussed. © The Author(s) 2015.

Embedded interruptions and task complexity influence schema-related cognitive load progression in an abstract learning task.

Science.gov (United States)

Wirzberger, Maria; Esmaeili Bijarsari, Shirin; Rey, Günter Daniel

2017-09-01

Cognitive processes related to schema acquisition comprise an essential source of demands in learning situations. Since the related amount of cognitive load is supposed to change over time, plausible temporal models of load progression based on different theoretical backgrounds are inspected in this study. A total of 116 student participants completed a basal symbol sequence learning task, which provided insights into underlying cognitive dynamics. Two levels of task complexity were determined by the amount of elements within the symbol sequence. In addition, interruptions due to an embedded secondary task occurred at five predefined stages over the task. Within the resulting 2x5-factorial mixed between-within design, the continuous monitoring of efficiency in learning performance enabled assumptions on relevant resource investment. From the obtained results, a nonlinear change of learning efficiency over time seems most plausible in terms of cognitive load progression. Moreover, different effects of the induced interruptions show up in conditions of task complexity, which indicate the activation of distinct cognitive mechanisms related to structural aspects of the task. Findings are discussed in the light of evidence from research on memory and information processing. Copyright © 2017 Elsevier B.V. All rights reserved.

The role of metabolism in bacterial persistence

Directory of Open Access Journals (Sweden)

Stephanie M. Amato

2014-03-01

Full Text Available Bacterial persisters are phenotypic variants with extraordinary tolerances toward antibiotics. Persister survival has been attributed to inhibition of essential cell functions during antibiotic stress, followed by reversal of the process and resumption of growth upon removal of the antibiotic. Metabolism plays a critical role in this process, since it participates in the entry, maintenance, and exit from the persister phenotype. Here, we review the experimental evidence that demonstrates the importance of metabolism to persistence, highlight the successes and potential for targeting metabolism in the search for anti-persister therapies, and discuss the current methods and challenges to understand persister physiology.

Prevalence and persistence of coagulase-negative Staphylococcus species in three dairy research herds.

Science.gov (United States)

Gillespie, B E; Headrick, S I; Boonyayatra, S; Oliver, S P

2009-02-16

Coagulase-negative Staphylococcus species (CNS) were isolated from 11.3% (1407 of 12,412) of mammary quarter milk samples obtained from cows in three dairy research herds in 2005. Approximately 27% (383/1407) of CNS was identified to the species level. The species distribution among those CNS identified from all herds was Staphylococcus chromogenes (48%), Staphylococcus hyicus (26%), Staphylococcus epidermidis (10%), Staphylococcus simulans (7%), Staphylococcus warneri (2%), Staphylococcus hominis (2%), Staphylococcus saprophyticus (1%), Staphylococcus xylosus (1%), Staphylococcus haemolyticus (Staphylococcus sciuri (Staphylococcus intermedius (<1%). Staphylococcuschromogenes was the predominant CNS isolated from all three herds; however, differences were seen in the prevalence of other CNS species. A total of 158 CNS (S. chromogenesn=66, S. hyicusn=38, S. epidermidisn=37, S. simulans n=10, and S. warneri n=7) were analyzed by pulsed-field gel electrophoresis (PFGE). The majority (33/41) of CNS isolated from the same mammary quarter on more than one occasion had the same PFGE pattern indicating persistence of the same infection over time. When all PFGE patterns for each CNS were analyzed, no common pulsotype was seen among the three herds indicating that CNS are quite diverse. Composite milk somatic cell count (SCC) data were obtained +/-14d of when CNS were isolated. Average milk SCC (5.32 log(10)/ml) for cows in which CNS was the only bacteria isolated was significantly higher than the average milk SCC (4.90 log(10)/ml) from cows with quarter milk samples that were bacteriologically negative.

Introduction: Persistent Modelling

DEFF Research Database (Denmark)

Ayres, Phil

2012-01-01

This introduction to 'Persistent Modelling – an extended role for architectural representation' identifies how the book probes the relationship between representation and the represented, in an architectural context. It discusses how the book presents an examination and discussion of historical......, familiar contemporary and, perhaps, not so familiar emerging manifestations of this relation. What persists from this probing, fully intact, is that representation and the represented remain inextricably related in our contemporary and emerging practices. What comes into focus is that the nature...

Students' network integration as a predictor of persistence in introductory physics courses

Science.gov (United States)

Zwolak, Justyna P.; Dou, Remy; Williams, Eric A.; Brewe, Eric

2017-06-01

Increasing student retention (successfully finishing a particular course) and persistence (continuing through a sequence of courses or the major area of study) is currently a major challenge for universities. While students' academic and social integration into an institution seems to be vital for student retention, research into the effect of interpersonal interactions is rare. We use network analysis as an approach to investigate academic and social experiences of students in the classroom. In particular, centrality measures identify patterns of interaction that contribute to integration into the university. Using these measures, we analyze how position within a social network in a Modeling Instruction (MI) course—an introductory physics course that strongly emphasizes interactive learning—predicts their persistence in taking a subsequent physics course. Students with higher centrality at the end of the first semester of MI are more likely to enroll in a second semester of MI. Moreover, we found that chances of successfully predicting individual student's persistence based on centrality measures are fairly high—up to 75%, making the centrality a good predictor of persistence. These findings suggest that increasing student social integration may help in improving persistence in science, technology, engineering, and mathematics fields.

Solar Energy Research and Education Foundation. Final reports by task

Energy Technology Data Exchange (ETDEWEB)

von Reis, K.; Waegel, A.S.; Totten, M.

1997-12-10

This document contains final reports for the following tasks: kiosk for the children`s museum renewable energy exhibit and display, internet promotional and educational material, Aurora renewable energy science and engineering, CD-ROM training materials, presentations and traveling display, radio show `Energy Matters`, and newspaper articles and weekly news column.

Promising high monetary rewards for future task performance increases intermediate task performance.

Directory of Open Access Journals (Sweden)

Claire M Zedelius

Full Text Available In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly. Results showed that high (vs. low rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner.

Promising high monetary rewards for future task performance increases intermediate task performance.

Science.gov (United States)

Zedelius, Claire M; Veling, Harm; Bijleveld, Erik; Aarts, Henk

2012-01-01

In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration) to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly). Results showed that high (vs. low) rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner.

Digital PCR as a tool to measure HIV persistence.

Science.gov (United States)

Rutsaert, Sofie; Bosman, Kobus; Trypsteen, Wim; Nijhuis, Monique; Vandekerckhove, Linos

2018-01-30

Although antiretroviral therapy is able to suppress HIV replication in infected patients, the virus persists and rebounds when treatment is stopped. In order to find a cure that can eradicate the latent reservoir, one must be able to quantify the persisting virus. Traditionally, HIV persistence studies have used real-time PCR (qPCR) to measure the viral reservoir represented by HIV DNA and RNA. Most recently, digital PCR is gaining popularity as a novel approach to nucleic acid quantification as it allows for absolute target quantification. Various commercial digital PCR platforms are nowadays available that implement the principle of digital PCR, of which Bio-Rad's QX200 ddPCR is currently the most used platform in HIV research. Quantification of HIV by digital PCR is proving to be a valuable improvement over qPCR as it is argued to have a higher robustness to mismatches between the primers-probe set and heterogeneous HIV, and forfeits the need for a standard curve, both of which are known to complicate reliable quantification. However, currently available digital PCR platforms occasionally struggle with unexplained false-positive partitions, and reliable segregation between positive and negative droplets remains disputed. Future developments and advancements of the digital PCR technology are promising to aid in the accurate quantification and characterization of the persistent HIV reservoir.

Intertwined effects of gender and migration status on persistence in SET study programmes

Science.gov (United States)

Guenther, Elisabeth Anna; Koeszegi, Sabine Theresia

2017-11-01

This paper explores the intersectional interference of gender and migration status on students' persistence at an Austrian University of Technology. While controlling for the pre-university education and performance indicators, we estimate the odds for the persistence of male and female students, as well as of students with diverse migration statuses. We use the enrolment data of students from 1998 to 2010. The analysis reveals remarkable and significant effects of gender and migration status, as well as intersectional interference effects from both social categories on persistence. Female and students with immigration status are less likely to persist, even if performance and previous relevant experiences are controlled. A segregated analysis of the student population sheds further light on the interlocked and entangled effects of the social ascriptions underlying gender and migration status. The analysis supports the proposition of the accumulation of (dis-)advantages along students' careers. The profound quantification of gender and migration status effects can be utilised as basis for further research and purposeful policy measures to increase persistence in Science, Engineering and Technology for students with diverse backgrounds.

High-Frequency Binaural Beats Increase Cognitive Flexibility: Evidence from Dual-Task Crosstalk.

Science.gov (United States)

Hommel, Bernhard; Sellaro, Roberta; Fischer, Rico; Borg, Saskia; Colzato, Lorenza S

2016-01-01

Increasing evidence suggests that cognitive-control processes can be configured to optimize either persistence of information processing (by amplifying competition between decision-making alternatives and top-down biasing of this competition) or flexibility (by dampening competition and biasing). We investigated whether high-frequency binaural beats, an auditory illusion suspected to act as a cognitive enhancer, have an impact on cognitive-control configuration. We hypothesized that binaural beats in the gamma range bias the cognitive-control style toward flexibility, which in turn should increase the crosstalk between tasks in a dual-task paradigm. We replicated earlier findings that the reaction time in the first-performed task is sensitive to the compatibility between the responses in the first and the second task-an indication of crosstalk. As predicted, exposing participants to binaural beats in the gamma range increased this effect as compared to a control condition in which participants were exposed to a continuous tone of 340 Hz. These findings provide converging evidence that the cognitive-control style can be systematically biased by inducing particular internal states; that high-frequency binaural beats bias the control style toward more flexibility; and that different styles are implemented by changing the strength of local competition and top-down bias.

Not all choices are created equal: Task-relevant choices enhance motor learning compared to task-irrelevant choices.

Science.gov (United States)

Carter, Michael J; Ste-Marie, Diane M

2017-12-01

Lewthwaite et al. (2015) reported that the learning benefits of exercising choice (i.e., their self-controlled condition) are not restricted to task-relevant features (e.g., feedback). They found that choosing one's golf ball color (Exp. 1) or choosing which of two tasks to perform at a later time plus which of two artworks to hang (Exp. 2) resulted in better retention than did being denied these same choices (i.e., yoked condition). The researchers concluded that the learning benefits derived from choice, whether irrelevant or relevant to the to-be-learned task, are predominantly motivational because choice is intrinsically rewarding and satisfies basic psychological needs. However, the absence of a group that made task-relevant choices and the lack of psychological measures significantly weakened their conclusions. Here, we investigated how task-relevant and task-irrelevant choices affect motor-skill learning. Participants practiced a spatiotemporal motor task in either a task-relevant group (choice over feedback schedule), a task-irrelevant group (choice over the color of an arm-wrap plus game selection), or a no-choice group. The results showed significantly greater learning in the task-relevant group than in both the task-irrelevant and no-choice groups, who did not differ significantly. Critically, these learning differences were not attributed to differences in perceptions of competence or autonomy, but instead to superior error-estimation abilities. These results challenge the perspective that motivational influences are the root cause of self-controlled learning advantages. Instead, the findings add to the growing evidence highlighting that the informational value gained from task-relevant choices makes a greater relative contribution to these advantages than motivational influences do.

The Persistence of Abnormal Returns: Analysis of Polish Manufacturing Industry

Directory of Open Access Journals (Sweden)

Marcin Puziak

2017-06-01

Full Text Available The ultimate goal of a company is to build the enterprise value, which is achievable thanks to abnormal profits generated in particular period. Moreover, firms are expected to take measures to maintain abnormal profit in the future. On the other hand, abnormal profits attract competitors, who increase competition and as a result abnormal profits disappear. The persistence of profit is a term that describes a situation, when the company is successful in maintaining the abnormal profit over time. The main aim of this paper is to investigate the persistence of abnormal profit in Polish manufacturing sector. In other words, the question is whether Polish manufacturing companies are able to maintain their abnormal profits over time. The persistence of abnormal profits is investigated using dynamic panel model with generalized method-of-moments estimators. The method is applied to a panel of 5303 Polish companies from manufacturing sector observed over the period 2006-2014. This paper contributes to the existing literature in two ways. First, analysis is performed for developing country. Second, analysis is performed both at the level of entire sector and at division level. Three main conclusions can be drawn from the conducted research: there are significant differences between profit rates within the same industry at division level; estimated persistence of abnormal profit coefficients are at moderate level; there are substantial differences between estimated persistence of profit coefficients for divisions in the same industry.

Good research practices for comparative effectiveness research: approaches to mitigate bias and confounding in the design of nonrandomized studies of treatment effects using secondary data sources: the International Society for Pharmacoeconomics and Outcomes Research Good Research Practices for Retrospective Database Analysis Task Force Report--Part II.

Science.gov (United States)

Cox, Emily; Martin, Bradley C; Van Staa, Tjeerd; Garbe, Edeltraut; Siebert, Uwe; Johnson, Michael L

2009-01-01

The goal of comparative effectiveness analysis is to examine the relationship between two variables, treatment, or exposure and effectiveness or outcome. Unlike data obtained through randomized controlled trials, researchers face greater challenges with causal inference with observational studies. Recognizing these challenges, a task force was formed to develop a guidance document on methodological approaches to addresses these biases. The task force was commissioned and a Chair was selected by the International Society for Pharmacoeconomics and Outcomes Research Board of Directors in October 2007. This report, the second of three reported in this issue of the Journal, discusses the inherent biases when using secondary data sources for comparative effectiveness analysis and provides methodological recommendations to help mitigate these biases. The task force report provides recommendations and tools for researchers to mitigate threats to validity from bias and confounding in measurement of exposure and outcome. Recommendations on design of study included: the need for data analysis plan with causal diagrams; detailed attention to classification bias in definition of exposure and clinical outcome; careful and appropriate use of restriction; extreme care to identify and control for confounding factors, including time-dependent confounding. Design of nonrandomized studies of comparative effectiveness face several daunting issues, including measurement of exposure and outcome challenged by misclassification and confounding. Use of causal diagrams and restriction are two techniques that can improve the theoretical basis for analyzing treatment effects in study populations of more homogeneity, with reduced loss of generalizability.

Cost-effectiveness analysis alongside clinical trials II-An ISPOR Good Research Practices Task Force report.

Science.gov (United States)

Ramsey, Scott D; Willke, Richard J; Glick, Henry; Reed, Shelby D; Augustovski, Federico; Jonsson, Bengt; Briggs, Andrew; Sullivan, Sean D

2015-03-01

Clinical trials evaluating medicines, medical devices, and procedures now commonly assess the economic value of these interventions. The growing number of prospective clinical/economic trials reflects both widespread interest in economic information for new technologies and the regulatory and reimbursement requirements of many countries that now consider evidence of economic value along with clinical efficacy. As decision makers increasingly demand evidence of economic value for health care interventions, conducting high-quality economic analyses alongside clinical studies is desirable because they broaden the scope of information available on a particular intervention, and can efficiently provide timely information with high internal and, when designed and analyzed properly, reasonable external validity. In 2005, ISPOR published the Good Research Practices for Cost-Effectiveness Analysis Alongside Clinical Trials: The ISPOR RCT-CEA Task Force report. ISPOR initiated an update of the report in 2014 to include the methodological developments over the last 9 years. This report provides updated recommendations reflecting advances in several areas related to trial design, selecting data elements, database design and management, analysis, and reporting of results. Task force members note that trials should be designed to evaluate effectiveness (rather than efficacy) when possible, should include clinical outcome measures, and should obtain health resource use and health state utilities directly from study subjects. Collection of economic data should be fully integrated into the study. An incremental analysis should be conducted with an intention-to-treat approach, complemented by relevant subgroup analyses. Uncertainty should be characterized. Articles should adhere to established standards for reporting results of cost-effectiveness analyses. Economic studies alongside trials are complementary to other evaluations (e.g., modeling studies) as information for decision

Canadian safeguards research and development in support of the IAEA program document outlining the various tasks which comprise the program

International Nuclear Information System (INIS)

1985-12-01

Canada has established a safeguards research and development program, the purpose of which is to supplement the resources of the International Atomic Energy Agency. The program of support is a coordinated effort for the development and application of safeguards techniques and instruments to facilities safeguarded by the IAEA. This document sets forth those tasks which comprise the program

A Comparison of For-Profit and Traditional Universities' Student Persistence, Graduation Rate, and Job Placement

Science.gov (United States)

Sandlin, Deborah L.

2017-01-01

This research project is a study comparing for-profit schools and traditional universities related to student persistence, graduation rate, and job placement. The results based on a sample size of 92 students indicate that there is no significant difference between persistence, graduation rates and successful job placement at either school. There…

Women in engineering: A case study in preparation, persistence, and response

Science.gov (United States)

Winkelman, Colin Kim

This qualitative case study examined women students' perceptions of major influences on their successful completion of a Bachelor of Science degree in nine different disciplines of engineering. In-depth interviews were conducted with 13 female engineering students at an Institute of Technology over the period of a school year. The conceptual framework of analysis linked theoretical principles to categories of analysis that were correlated to three outcomes: preparation, persistence, and response. Emergent properties generated from in-depth interviews were then linked to the categories of preparation, interest-congruence, gender identity, social acceptance, campus culture, learning styles, classroom and faculty relations, sense of accomplishment, tokenism, career expectations, and family planning. Data collection was triangulated through individual interviews and a focus group with the 13 respondents and comparisons to quantitative research outcomes concerning self-confidence, persistence, satisfaction, and career expectations. The findings generally support the theories and propositions outlined in the conceptual framework constructed for this study. The most important of these findings include the impact of social conditioning on gender and academic preparation, the correlation of peer group relations to persistence, and the future expectations female students derive from their experiences over their 4 years of study. The data strongly suggest that traditional gender roles are a social conditioning process that can be overcome, permitting women to succeed in nontraditional academic career fields. Further research could build on these findings to explore social changes in attitudes about women engineers in the workplace, comparisons between men and women's persistence styles, and the importance of science and mathematics intervention programs for girls.

Relationship between Occupational Maladjustment and Task ...

African Journals Online (AJOL)

Consequently the present researchers motivated by this fact set out to determine the level of relationship between occupational maladjustment and task performance of civil servants in Anambra state. Three research questions and one hypothesis guided the study. The design for the study is correlational survey used to ...

Correlates of persistent thinness in black and white young women

NARCIS (Netherlands)

Franko, DL; Thompson, D; Russell, R; Schreiber, GB; Crawford, PB; Daniels, [No Value; Striegel-Moore, RH

2005-01-01

Objective: To examine health and psychosocial correlates of persistent thinness in black and white young adult women. Research Methods and Procedures: 1830 females (n = 988 black, n = 842 white) who participated in the National Heart, Lung, and Blood Institute Growth and Health Study were asked to

Persistent and recurrent hyperparathyroidism.

Science.gov (United States)

Guerin, Carole; Paladino, Nunzia Cinzia; Lowery, Aoife; Castinetti, Fréderic; Taieb, David; Sebag, Fréderic

2017-06-01

Despite remarkable progress in imaging modalities and surgical management, persistence or recurrence of primary hyperparathyroidism (PHPT) still occurs in 2.5-5% of cases of PHPT. The aim of this review is to expose the management of persistent and recurrent hyperparathyroidism. A literature search was performed on MEDLINE using the search terms "recurrent" or "persistent" and "hyperparathyroidism" within the past 10 years. We also searched the reference lists of articles identified by this search strategy and selected those we judged relevant. Before considering reoperation, the surgeon must confirm the diagnosis of PHPT. Then, the patient must be evaluated with new imaging modalities. A single adenoma is found in 68% of cases, multiglandular disease in 28%, and parathyroid carcinoma in 3%. Others causes (<1%) include parathyromatosis and graft recurrence. The surgeon must balance the benefits against the risks of a reoperation (permanent hypocalcemia and recurrent laryngeal nerve palsy). If surgery is necessary, a focused approach can be considered in cases of significant imaging foci, but in the case of multiglandular disease, a bilateral neck exploration could be necessary. Patients with multiple endocrine neoplasia syndromes are at high risk of recurrence and should be managed regarding their hereditary pathology. The cure rate of persistent-PHPT or recurrent-PHPT in expert centers is estimated from 93 to 97%. After confirming the diagnosis of PHPT, patients with persistent-PHPT and recurrent-PHPT should be managed in an expert center with all dedicated competencies.

Advert saliency distracts children's visual attention during task-oriented internet use

Directory of Open Access Journals (Sweden)

Nils eHolmberg

2014-02-01

Full Text Available The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9-year-old and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual processing involved in solving these tasks, this study allows us to infer how two types of visual saliency affect children's attentional behavior, and whether such behavioral effects also impacts their task performance. Analyses show that low-level visual features and task relevance in online adverts have different effects on performance measures and process measures respectively. Whereas task performance is stable with regard to several advert saliency conditions, a marked effect is seen on children's gaze behavior. On the other hand, task performance is shown to be more sensitive to individual differences such as age, gender and level of gaze control. The results provide evidence about cognitive and behavioral distraction effects in children's task-oriented internet use caused by visual saliency in online adverts. The experiment suggests that children to some extent are able to compensate for behavioral effects caused by distracting visual stimuli when solving prospective memory tasks. Suggestions are given for further research into the interdiciplinary area between media research and cognitive science.

Adaptive memory: animacy effects persist in paired-associate learning.

Science.gov (United States)

VanArsdall, Joshua E; Nairne, James S; Pandeirada, Josefa N S; Cogdill, Mindi

2015-01-01

Recent evidence suggests that animate stimuli are remembered better than matched inanimate stimuli. Two experiments tested whether this animacy effect persists in paired-associate learning of foreign words. Experiment 1 randomly paired Swahili words with matched animate and inanimate English words. Participants were told simply to learn the English "translations" for a later test. Replicating earlier findings using free recall, a strong animacy advantage was found in this cued-recall task. Concerned that the effect might be due to enhanced accessibility of the individual responses (e.g., animates represent a more accessible category), Experiment 2 selected animate and inanimate English words from two more constrained categories (four-legged animals and furniture). Once again, an advantage was found for pairs using animate targets. These results argue against organisational accounts of the animacy effect and potentially have implications for foreign language vocabulary learning.

What is the Value Proposition of Persistent Identifiers?

Science.gov (United States)

Klump, Jens; Huber, Robert

2017-04-01

Persistent identifiers (PID) are widely used today in scientific communication and documentation. Global unique identification plus persistent resolution of links to referenced digital research objects have been strong selling points for PID Systems as enabling technical infrastructures. Novel applications of PID Systems in research now go beyond the identification of file based objects such as literature or data sets and include the identification of dynamically changing datasets accessed through web services, physical objects, persons and organisations. But not only do we see more use cases but also a proliferation of identifier systems. An analysis of PID Systems used by 1381 repositories listed in the Registry of Research Data Repositories (re3data.org, status of 14 Dec 2015) showed that many disciplinary data repositories make use of PID that are not among the systems promoted by the libraries and publishers (DOI, PURL, ARK). This indicates that a number of communities have developed their own PID Systems. This begs the question, do we need more identifier systems? What makes their value proposition more appealing than those of already existing systems? On the other hand, some of these new use cases deal with entities outside the digital domain, the original scope of application for PIDs. It is therefore necessary to critically appraise the value propositions of available PID Systems and compare these against the requirements of new use cases for PID. Undoubtedly, DOI are the most used persistent identifier in scholarly communication. It was originally designed "to link customers with publishers, facilitate electronic commerce, and enable copyright management systems." Today, the DOI system is described as providing "a technical and social infrastructure for the registration and use of persistent interoperable identifiers for use on digital networks". This example shows how value propositions can change over time. Additional value can be gained by cross

Pediatric patient-reported outcome instruments for research to support medical product labeling: report of the ISPOR PRO good research practices for the assessment of children and adolescents task force.

Science.gov (United States)

Matza, Louis S; Patrick, Donald L; Riley, Anne W; Alexander, John J; Rajmil, Luis; Pleil, Andreas M; Bullinger, Monika

2013-06-01

Patient-reported outcome (PRO) instruments for children and adolescents are often included in clinical trials with the intention of collecting data to support claims in a medical product label. The purpose of the current task force report is to recommend good practices for pediatric PRO research that is conducted to inform regulatory decision making and support claims made in medical product labeling. The recommendations are based on the consensus of an interdisciplinary group of researchers who were assembled for a task force associated with the International Society for Pharmacoeconomics and Outcomes Research (ISPOR). In those areas in which supporting evidence is limited or in which general principles may not apply to every situation, this task force report identifies factors to consider when making decisions about the design and use of pediatric PRO instruments, while highlighting issues that require further research. Five good research practices are discussed: 1) Consider developmental differences and determine age-based criteria for PRO administration: Four age groups are discussed on the basis of previous research (<5 years old, 5-7 years, 8-11 years, and 12-18 years). These age groups are recommended as a starting point when making decisions, but they will not fit all PRO instruments or the developmental stage of every child. Specific age ranges should be determined individually for each population and PRO instrument. 2) Establish content validity of pediatric PRO instruments: This section discusses the advantages of using children as content experts, as well as strategies for concept elicitation and cognitive interviews with children. 3) Determine whether an informant-reported outcome instrument is necessary: The distinction between two types of informant-reported measures (proxy vs. observational) is discussed, and recommendations are provided. 4) Ensure that the instrument is designed and formatted appropriately for the target age group. Factors to

Entering into dialogue about the mathematical value of contextual mathematising tasks

Science.gov (United States)

Yoon, Caroline; Chin, Sze Looi; Moala, John Griffith; Choy, Ban Heng

2018-03-01

Our project seeks to draw attention to the rich mathematical thinking that is generated when students work on contextual mathematising tasks. We use a design-based research approach to create ways of reporting that raise the visibility of this rich mathematical thinking while retaining and respecting its complexity. These reports will be aimed for three classroom stakeholders: (1) students, who wish to reflect on and enhance their mathematical learning; (2) teachers, who wish to integrate contextual mathematising tasks into their teaching practice and (3) researchers, who seek rich tasks for generating observable instances of mathematical thinking and learning. We anticipate that these reports and the underlying theoretical framework for creating them will contribute to greater awareness of and appreciation for the mathematical value of contextual mathematising tasks in learning, teaching and research.

Education Research in Physical Therapy: Visions of the Possible.

Science.gov (United States)

Jensen, Gail M; Nordstrom, Terrence; Segal, Richard L; McCallum, Christine; Graham, Cecilia; Greenfield, Bruce

2016-12-01

Education research has been labeled the "hardest science" of all, given the challenges of teaching and learning in an environment encompassing a mixture of social interactions, events, and problems coupled with a persistent belief that education depends more on common sense than on disciplined knowledge and skill. The American Educational Research Association specifies that education research-as a scientific field of study-examines teaching and learning processes that shape educational outcomes across settings and that a learning process takes place throughout a person's life. The complexity of learning and learning environments requires not only a diverse array of research methods but also a community of education researchers committed to exploring critical questions in the education of physical therapists. Although basic science research and clinical research in physical therapy have continued to expand through growth in the numbers of funded physical therapist researchers, the profession still lacks a robust and vibrant community of education researchers. In this perspective article, the American Council of Academic Physical Therapy Task Force on Education Research proposes a compelling rationale for building a much-needed foundation for education research in physical therapy, including a set of recommendations for immediate action. © 2016 American Physical Therapy Association.

Task-specific compensation and recovery following focal motor cortex lesion in stressed rats.

Science.gov (United States)

Kirkland, Scott W; Smith, Lori K; Metz, Gerlinde A

2012-03-01

One reason for the difficulty to develop effective therapies for stroke is that intrinsic factors, such as stress, may critically influence pathological mechanisms and recovery. In cognitive tasks, stress can both exaggerate and alleviate functional loss after focal ischemia in rodents. Using a comprehensive motor assessment in rats, this study examined if chronic stress and corticosterone treatment affect skill recovery and compensation in a task-specific manner. Groups of rats received daily restraint stress or oral corticosterone supplementation for two weeks prior to a focal motor cortex lesion. After lesion, stress and corticosterone treatments continued for three weeks. Motor performance was assessed in two skilled reaching tasks, skilled walking, forelimb inhibition, forelimb asymmetry and open field behavior. The results revealed that persistent stress and elevated corticosterone levels mainly limit motor recovery. Treated animals dropped larger amounts of food in successful reaches and showed exaggerated loss of forelimb inhibition early after lesion. Stress also caused a moderate, but non-significant increase in infarct size. By contrast, stress and corticosterone treatments promoted reaching success and other quantitative measures in the tray reaching task. Comparative analysis revealed that improvements are due to task-specific development of compensatory strategies. These findings suggest that stress and stress hormones may partially facilitate task-specific and adaptive compensatory movement strategies. The observations support the notion that hypothalamic-pituitary-adrenal axis activation may be a key determinant of recovery and motor system plasticity after ischemic stroke.

Persistence Characteristics of Australian Rainfall Anomalies

Science.gov (United States)

Simmonds, Ian; Hope, Pandora

1997-05-01

Using 79 years (1913-1991) of Australian monthly precipitation data we examined the nature of the persistence of rainfall anomalies. Analyses were performed for four climate regions covering the country, as well as for the entire Australian continent. We show that rainfall over these regions has high temporal variability and that annual rainfall amounts over all five sectors vary in phase and are, with the exception of the north-west region, significantly correlated with the Southern Oscillation Index (SOI). These relationships were particularly strong during the spring season.It is demonstrated that Australian rainfall exhibits statistically significant persistence on monthly, seasonal, and (to a limited extent) annual time-scales, up to lags of 3 months and one season and 1 year. The persistence showed strong seasonal dependence, with each of the five regions showing memory out to 4 or 5 months from winter and spring. Many aspects of climate in the Australasian region are known to have undergone considerable changes about 1950. We show this to be true for persistence also; its characteristics identified for the entire record were present during the 1951--1980 period, but virtually disappeared in the previous 30-year period.Much of the seasonal distribution of rainfall persistence on monthly time-scales, particularly in the east, is due to the influence of the SOI. However, most of the persistence identified in winter and spring in the north-west is independent of the ENSO phenomenon.Rainfall anomalies following extreme dry and wet months, seasons and years (lowest and highest two deciles) persisted more than would be expected by chance. For monthly extreme events this was more marked in the winter semester for the wet events, except in the south-east region. In general, less persistence was found for the extreme seasons. Although the persistence of dry years was less than would have been expected by chance, the wet years appear to display persistence.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

Science.gov (United States)

Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

Directory of Open Access Journals (Sweden)

David M Sanbonmatsu

Full Text Available The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking

Science.gov (United States)

Sanbonmatsu, David M.; Strayer, David L.; Medeiros-Ward, Nathan; Watson, Jason M.

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants’ perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation – high levels of impulsivity and sensation seeking – reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control - low scorers on the Operation Span task and persons high in impulsivity - tended to report higher levels of multi-tasking activity. PMID:23372720

Medication persistence in Turkish children and adolescents with attention-deficit/hyperactivity disorder.

Science.gov (United States)

Ayaz, Muhammed; Ayaz, Ayşe Burcu; Soylu, Nusret; Yüksel, Serhat

2014-10-01

The aim of this study was to investigate medication persistence in Turkish children and adolescents with attention-deficit/hyperactivity disorder (ADHD). The effects of sociodemographic characteristics, symptom severity of ADHD, comorbidity, and treatment-related factors influencing medication persistence in children diagnosed with ADHD were studied. Medication persistence over a continuous 12 month period was evaluated for 877 children and adolescents between 6 and 18 years of age, who were diagnosed with ADHD for the first time and started to receive medication. Medication persistence was determined according to whether or not taking the prescribed medication continued for 12 months after the initiation of treatment. Whereas the symptom severity of ADHD was assessed by using the Turgay Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV)-based Child and Adolescent Behaviour Disorders Screening and Rating Scale-Parents Form (T-DSM-IV-S), perceived medication efficacy after the first treatment was evaluated by the Clinical Global Impressions-Improvement Scale (CGI-I). In this study, medication persistence over a continuous 12 month period occurred at a rate of 30.2% (n=265) in the subjects studied. The hierarchical regression analysis conducted in this research revealed that younger age, higher hyperactivity/impulsivity symptom severity, use of long-acting methylphenidate, addition of another ADHD medication, addition of other psychotropic medications, absence of side effects, and perceived medication efficacy were associated with successful medication persistence over a continuous 12 month period. Understanding the factors that affect medication persistence in ADHD may improve treatment efficacy and symptom control, while minimizing future risks.

Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm.

Science.gov (United States)

Arber, Madeleine M; Ireland, Michael J; Feger, Roy; Marrington, Jessica; Tehan, Joshua; Tehan, Gerald

2017-01-01

Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource) models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration). Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors) as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research.

Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm

Directory of Open Access Journals (Sweden)

Madeleine M. Arber

2017-09-01

Full Text Available Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration. Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research.

A hugh marketing research task: birth control.

Science.gov (United States)

Simon, J L

1968-02-01

Research in underdeveloped countries to sell family planning is discussed. The article also aims at pinpointing other possible research areas. Census reports were actually the earliest work relevant to birth control. Later came the research on psychosocial factors affecting family size in developed countries. After World War I, client oriented research into family planning began. The history of this type of research is discussed with more emphasis on the surveys of the knowledge, attitude and contraception practices (KAP) in various countries. The author claims the KAP surveys to be the largest worldwide market research job ever done. Propagands campaigns, contraceptive costs, bonuses for contraceptive practices, and effectiveness of persuasion techniques are discussed.

The First Year of College: Understanding Student Persistence in Engineering

OpenAIRE

Hayden, Marina Calvet

2017-01-01

This research study aimed to expand our understanding of the factors that influence student persistence in engineering. The unique experiences of engineering students were examined as they transitioned into and navigated their first year of college at a public research university in California. Most students provided similar responses with respect to the way they experienced the transition to college and social life. There was, however, wide student response variation regarding their experien...

Reconciling the influence of task-set switching and motor inhibition processes on stop signal after-effects.

Science.gov (United States)

Anguera, Joaquin A; Lyman, Kyle; Zanto, Theodore P; Bollinger, Jacob; Gazzaley, Adam

2013-01-01

Executive response functions can be affected by preceding events, even if they are no longer associated with the current task at hand. For example, studies utilizing the stop signal task have reported slower response times to "GO" stimuli when the preceding trial involved the presentation of a "STOP" signal. However, the neural mechanisms that underlie this behavioral after-effect are unclear. To address this, behavioral and electroencephalography (EEG) measures were examined in 18 young adults (18-30 years) on "GO" trials following a previously "Successful Inhibition" trial (pSI), a previously "Failed Inhibition" trial (pFI), and a previous "GO" trial (pGO). Like previous research, slower response times were observed during both pSI and pFI trials (i.e., "GO" trials that were preceded by a successful and unsuccessful inhibition trial, respectively) compared to pGO trials (i.e., "GO" trials that were preceded by another "GO" trial). Interestingly, response time slowing was greater during pSI trials compared to pFI trials, suggesting executive control is influenced by both task set switching and persisting motor inhibition processes. Follow-up behavioral analyses indicated that these effects resulted from between-trial control adjustments rather than repetition priming effects. Analyses of inter-electrode coherence (IEC) and inter-trial coherence (ITC) indicated that both pSI and pFI trials showed greater phase synchrony during the inter-trial interval compared to pGO trials. Unlike the IEC findings, differential ITC was present within the beta and alpha frequency bands in line with the observed behavior (pSI > pFI > pGO), suggestive of more consistent phase synchrony involving motor inhibition processes during the ITI at a regional level. These findings suggest that between-trial control adjustments involved with task-set switching and motor inhibition processes influence subsequent performance, providing new insights into the dynamic nature of executive control.

The task-to-task communication between computers

International Nuclear Information System (INIS)

Lin Shuzi; Zhang Bingyun; Zhao Weiren

1992-01-01

The task-to-task communication is used in the Institute of High Energy Physics. The BES (Beijing Spectrometer) uses the communication mode to take some of the BEPC (Beijing Electron Positron Collider) running parameters needed by BES experiments in a periodic time. The authors describe the principle of transparent task-to-task communication and how to use it in BES on-line data acquisition system

Biomedical applications engineering tasks

Science.gov (United States)

Laenger, C. J., Sr.

1976-01-01

The engineering tasks performed in response to needs articulated by clinicians are described. Initial contacts were made with these clinician-technology requestors by the Southwest Research Institute NASA Biomedical Applications Team. The basic purpose of the program was to effectively transfer aerospace technology into functional hardware to solve real biomedical problems.

Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease.

Science.gov (United States)

Middelveen, Marianne J; Sapi, Eva; Burke, Jennie; Filush, Katherine R; Franco, Agustin; Fesler, Melissa C; Stricker, Raphael B

2018-04-14

Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borrelia burgdorferi , in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of ten control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borrelia burgdorferi by three distinct polymerase chain reaction (PCR)-based approaches. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.

Are gamers better crossers? An examination of action video game experience and dual task effects in a simulated street crossing task.

Science.gov (United States)

Gaspar, John G; Neider, Mark B; Crowell, James A; Lutz, Aubrey; Kaczmarski, Henry; Kramer, Arthur F

2014-05-01

A high-fidelity street crossing simulator was used to test the hypothesis that experienced action video game players are less vulnerable than non-gamers to dual task costs in complex tasks. Previous research has shown that action video game players outperform nonplayers on many single task measures of perception and attention. It is unclear, however, whether action video game players outperform nonplayers in complex, divided attention tasks. Experienced action video game players and nongamers completed a street crossing task in a high-fidelity simulator. Participants walked on a manual treadmill to cross the street. During some crossings, a cognitively demanding working memory task was added. Dividing attention resulted in more collisions and increased decision making time. Of importance, these dual task costs were equivalent for the action video game players and the nongamers. These results suggest that action video game players are equally susceptible to the costs of dividing attention in a complex task. Perceptual and attentional benefits associated with action video game experience may not translate to performance benefits in complex, real-world tasks.

Research on Evaluation Model for Secondary Task Driving Safety Based on Driver Eye Movements

Directory of Open Access Journals (Sweden)

Lisheng Jin

2014-01-01

Full Text Available This study was designed to gain insight into the influence of performing different types of secondary task while driving on driver eye movements and to build a safety evaluation model for secondary task driving. Eighteen young drivers were selected and completed the driving experiment on a driving simulator. Measures of fixations, saccades, and blinks were analyzed. Based on measures which had significant difference between the baseline and secondary tasks driving conditions, the evaluation index system was built. Method of principal component analysis (PCA was applied to analyze evaluation indexes data in order to obtain the coefficient weights of indexes and build the safety evaluation model. Based on evaluation scores, the driving safety was grouped into five levels (very high, high, average, low, and very low using K-means clustering algorithm. Results showed that secondary task driving severely distracts the driver and the evaluation model built in this study could estimate driving safety effectively under different driving conditions.

Within-person relationship between self-efficacy and performance across trials. Effect of task objective and task type.

Science.gov (United States)

Hepler, Teri J; Ritchie, Jason; Hill, Christopher R

2017-07-05

Self-efficacy has been shown to be a consistent, positive predictor of between-persons performance in sport. However, there have been equivocal results regarding the influence of self-efficacy on a person's performance over time. This study investigated the influence of self-efficacy on motor skill performance across trials with respect to two different task objectives and task types. Participants (N=84) performed 4 blocks of 10 trials of a dart throwing (closed skill) and a hitting (open skill) task under 2 different task objectives: competitive and goal-striving. For the goal-striving condition, success was defined as reaching a pre-determined performance level. The competitive condition involved competing against an opponent. Hierarchical linear modeling was used to examine the influence of past performance and self-efficacy on the within-person performance across multiple trials. Previous performance was negatively related with subsequent performance on all conditions. Self-efficacy was not a significant predictor of performance on any of the conditions. While task objective and task type did not moderate the efficacy-performance relationship in the current study, it is important to consider the role of other moderators in future research.

Contributions to Persistence Theory

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Du Dong

2014-12-01

Full Text Available Persistence theory discussed in this paper is an application of algebraic topology (Morse Theory [29] to Data Analysis, precisely to qualitative understanding of point cloud data, or PCD for short. PCD can be geometrized as a filtration of simplicial complexes (Vietoris-Rips complex [25] [36] and the homology changes of these complexes provide qualitative information about the data. Bar codes describe the changes in homology with coefficients in a fixed field. When the coefficient field is ℤ2, the calculation of bar codes is done by ELZ algorithm (named after H. Edelsbrunner, D. Letscher, and A. Zomorodian [20]. When the coefficient field is ℝ, we propose an algorithm based on the Hodge decomposition [17]. With Dan Burghelea and Tamal K. Dey we developed a persistence theory which involves level sets discussed in Section 4. We introduce and discuss new computable invariants, the “relevant level persistence numbers” and the “positive and negative bar codes”, and explain how they are related to the bar codes for level persistence. We provide enhancements and modifications of ELZ algorithm to calculate such invariants and illustrate them by examples.

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans.

Science.gov (United States)

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W Pieter; Kessels, Roy P C; Daselaar, Sander M

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories.

THE SPECIFIC AND GENERAL NATURE OF LOGISTICS TASKS

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Beáta Sz. G. Pató

2016-12-01

Full Text Available There are many ways to define and to describe jobs and assigning to people. This is a key issue in both blue collar and in white collar jobs. This analysis focuses on the work content of jobs in logistics. However, the methodology allows the exploration of closely related issues to determine competence requirements as well. Jobs can be seen to have bearing on many areas including effectiveness, efficiency of individual and organizational level, social and political issues. The purpose of the research carried out by authors was to identify the necessary competencies in logistics jobs. It included the analysis of the tasks using company document (job description analysis in order to identify the tasks and required competencies. Researchers extracted and then standardized the verb - noun pairs which described the tasks. The frequency of these pairs gave the weight of the task in a job. This method allowed the researchers to determine the overlapping rate of activities in different fields (trade, transport, comprehensive activities. It was found that the most different/independent field in the terms of similarities is warehousing. Results suggest the rethinking of the training content in order to find the right balance between the general and specific competencies. They also help organizations to optimize the composition of cross-functional staff.

Gate-controlled switching between persistent and inverse persistent spin helix states

International Nuclear Information System (INIS)

Yoshizumi, K.; Sasaki, A.; Kohda, M.; Nitta, J.

2016-01-01

We demonstrate gate-controlled switching between persistent spin helix (PSH) state and inverse PSH state, which are detected by quantum interference effect on magneto-conductance. These special symmetric spin states showing weak localization effect give rise to a long spin coherence when the strength of Rashba spin-orbit interaction (SOI) is close to that of Dresselhaus SOI. Furthermore, in the middle of two persistent spin helix states, where the Rashba SOI can be negligible, the bulk Dresselhaus SOI parameter in a modulation doped InGaAs/InAlAs quantum well is determined.

Gate-controlled switching between persistent and inverse persistent spin helix states

Energy Technology Data Exchange (ETDEWEB)

Yoshizumi, K.; Sasaki, A.; Kohda, M.; Nitta, J. [Department of Materials Science, Tohoku University, Sendai 980-8579 (Japan)

2016-03-28

We demonstrate gate-controlled switching between persistent spin helix (PSH) state and inverse PSH state, which are detected by quantum interference effect on magneto-conductance. These special symmetric spin states showing weak localization effect give rise to a long spin coherence when the strength of Rashba spin-orbit interaction (SOI) is close to that of Dresselhaus SOI. Furthermore, in the middle of two persistent spin helix states, where the Rashba SOI can be negligible, the bulk Dresselhaus SOI parameter in a modulation doped InGaAs/InAlAs quantum well is determined.

Thalamo-cortical activation and connectivity during response preparation in adults with persistent and remitted ADHD.

Science.gov (United States)

Clerkin, Suzanne M; Schulz, Kurt P; Berwid, Olga G; Fan, Jin; Newcorn, Jeffrey H; Tang, Cheuk Y; Halperin, Jeffrey M

2013-09-01

The neural correlates of stimulus-driven processes, such as response preparation, have been posited to be associated with the onset of attention deficit hyperactivity disorder (ADHD) while being distinct from the neural mechanisms associated with recovery. The authors tested this hypothesis in adults with remitted and persistent ADHD. Thirty-eight young adults who were diagnosed with combined-type ADHD in childhood (probands) and 32 carefully matched comparison subjects were followed longitudinally and scanned with functional MRI while performing an event-related cued reaction time task. Probands were characterized as individuals with persistent or remitted ADHD. Differences in thalamo-cortical activation and functional connectivity during response preparation between comparison subjects and probands and between individuals with persistent ADHD and those with remitted ADHD were assessed by contrasting neural activation and functional connectivity during cue or noncue events. Probands exhibited less cue-related activation than comparison subjects in the thalamus, anterior cingulate cortex, supplementary motor area, inferior parietal lobe, and dorsolateral prefrontal cortex despite similar overall patterns of activation. There were no differences in activation between individuals in the remitted ADHD group and those in the persistent ADHD group in any hypothesized regions. However, cue-related functional connectivity between the right thalamus and brainstem was greater in comparison subjects relative to probands, and cue-related connectivity was greater between the right thalamus and prefrontal regions in individuals with remitted ADHD relative to those with persistent ADHD. Decreased thalamo-cortical activation during response preparation was present in adults diagnosed with ADHD in childhood regardless of symptom remission in adulthood, and may be partly driven by less functional coordination between the brainstem and thalamus. Greater functional integration of the

Reliable and Persistent Identification of Linked Data Elements

Science.gov (United States)

Wood, David

Linked Data techniques rely upon common terminology in a manner similar to a relational database'vs reliance on a schema. Linked Data terminology anchors metadata descriptions and facilitates navigation of information. Common vocabularies ease the human, social tasks of understanding datasets sufficiently to construct queries and help to relate otherwise disparate datasets. Vocabulary terms must, when using the Resource Description Framework, be grounded in URIs. A current bestpractice on the World Wide Web is to serve vocabulary terms as Uniform Resource Locators (URLs) and present both human-readable and machine-readable representations to the public. Linked Data terminology published to theWorldWideWeb may be used by others without reference or notification to the publishing party. That presents a problem: Vocabulary publishers take on an implicit responsibility to maintain and publish their terms via the URLs originally assigned, regardless of the inconvenience such a responsibility may cause. Over the course of years, people change jobs, publishing organizations change Internet domain names, computers change IP addresses,systems administrators publish old material in new ways. Clearly, a mechanism is required to manageWeb-based vocabularies over a long term. This chapter places Linked Data vocabularies in context with the wider concepts of metadata in general and specifically metadata on the Web. Persistent identifier mechanisms are reviewed, with a particular emphasis on Persistent URLs, or PURLs. PURLs and PURL services are discussed in the context of Linked Data. Finally, historic weaknesses of PURLs are resolved by the introduction of a federation of PURL services to address needs specific to Linked Data.

Differential facilitative effects of glucose administration on Stroop task conditions.

Science.gov (United States)

Brandt, Karen R; Gibson, E Leigh; Rackie, James M

2013-12-01

Previous research has demonstrated that glucose administration improves memory performance. These glucose facilitation effects have been most reliably demonstrated in medial temporal lobe tasks with the greatest effects found for cognitively demanding tasks. The aim of the proposed research was to first explore whether such effects might be demonstrated in a frontal lobe task. A second aim was to investigate whether any beneficial effects of glucose may arise more prominently under tasks of increasing cognitive demand. To achieve these aims, the Stroop Task was administered to participants and effects of a drink of glucose (25 g) were compared with an aspartame-sweetened control drink on performance in young adults. Results demonstrated that glucose ingestion significantly reduced RTs in the congruent and incongruent conditions. No effect on error rates was observed. Of most importance was the finding that this glucose facilitative effect was significantly greatest in the most cognitively demanding task, that is, the incongruent condition. The present results support the contention that the glucose facilitation effect is most robust under conditions of enhanced task difficulty and demonstrate that such benefits extend to frontal lobe function.

Demographics of antibiotic persistence

DEFF Research Database (Denmark)

Kollerova, Silvia; Jouvet, Lionel; Steiner, Ulrich

Persister cells, cells that can survive antibiotic exposure but lack heritable antibiotic resistance, are assumed to play a crucial role for the evolution of antibiotic resistance. Persistence is a stage associated with reduced metabolic activity. Most previous studies have been done on batch...... even play a more prominent role for the evolution of resistance and failures of medical treatment by antibiotics as currently assumed....

Task analysis and support for problem solving tasks

International Nuclear Information System (INIS)

Bainbridge, L.

1987-01-01

This paper is concerned with Task Analysis as the basis for ergonomic design to reduce human error rates, rather than for predicting human error rates. Task Analysis techniques usually provide a set of categories for describing sub tasks, and a framework describing the relations between sub-tasks. Both the task type categories and their organisation have implications for optimum interface and training design. In this paper, the framework needed for considering the most complex tasks faced by operators in process industries is discussed such as fault management in unexpected situations, and what is likely to minimise human error in these circumstances. (author)

Final Technical Report Transport Task Force Activities

International Nuclear Information System (INIS)

P.W. Terry

2006-01-01

The Transport Task Force has functioned as the primary scientific organization in the area of magnetic-fusion confinement and transport since its inception in 1988. It has defined and set research directions, coordinated broad research efforts, advocated new funding initiatives, and created a highly successful and widely admired interactive culture between experiment, theory and modeling. The Transport Task Force carries out its activities under the direction of its chair and the Executive Committee. The Executive Committee is comprised of the leaders and deputy leaders of the scientific working groups. The working groups are structured and organized according to research needs and priorities and have been organized around the areas of Core Transport, H Mode and Pedestal, Fast Particle Transport, Transient Transport Phenomena, and Modeling and Simulation. A steering committee provides advise on TTF activities. Further information on the working groups and the structure and management of the TTF can be found at http://psfcwww2.psfc.mit.edu/ttf/index.html. The TTF holds an annual workshop. A summary of the workshops held during the period of this report is given in Appendix I. During the period of this report the Transport Task Force was involved in several significant activities. Foremost of these was a sweeping review of the status of transport science, the key research tasks for progress during the next 5-10 years, and a proposal for a funding initiative to ensure application of adequate resources to these problems. The conclusions of this study were incorporated into a white paper, which is copied below in Appendix II. Other significant activities have included the introduction of an extended, ongoing discussion on verification and validation as a requisite for defining and codifying the path toward predictive capability, the orchestration of a gradual shift of focus from ion thermal confinement to electron thermal confinement, and a joining of efforts on edge

A Note on the Factor Structure of Some Piagetian Tasks.

Science.gov (United States)

Lawson, Anton E.; Nordland, Floyd H.

Some evidence supports the hypothesis that formal operational reasoning ability (at least that measured by Piagetian tasks) is a unified process. The purpose of this research was to determine: (1) if conservation tasks, such as conservation of number, liquid amount, weight and volume, are unifactor; and (2) if conservation tasks form a scale of…

Form-based Approaches vs. Task-Based Approaches

Directory of Open Access Journals (Sweden)

Zahra Talebi

2015-07-01

Full Text Available This study aimed at investigating whether task-based approaches bear any superiority to that of more traditional ones evident in presentation-practice- and production phase .to fulfill the purpose of the study, the participants within the age range of 11-19, took part in the study. Following a pretest, treatment, and a posttest, the obtained data was analyzed using analysis of covariance (ANCOVA to examine the effects of the variables. The results of the analysis showed that participants in the PPP group did significantly better in the grammar recognition of the posttest than that of the task group. However, their counterparts in the task group gained better scores in the writing section of the test .this research study provided evidence in support of task proponents' claim in the merit of task-based activity in raising learners' implicit knowledge claiming to play the primary role in spontaneous speech.

Using Benchmarking To Strengthen the Assessment of Persistence.

Science.gov (United States)

McLachlan, Michael S; Zou, Hongyan; Gouin, Todd

2017-01-03

Chemical persistence is a key property for assessing chemical risk and chemical hazard. Current methods for evaluating persistence are based on laboratory tests. The relationship between the laboratory based estimates and persistence in the environment is often unclear, in which case the current methods for evaluating persistence can be questioned. Chemical benchmarking opens new possibilities to measure persistence in the field. In this paper we explore how the benchmarking approach can be applied in both the laboratory and the field to deepen our understanding of chemical persistence in the environment and create a firmer scientific basis for laboratory to field extrapolation of persistence test results.

The Persistence of Outmoded Ideas in High School Geography Texts

Science.gov (United States)

Jackson, Richard H.

1976-01-01

Selected secondary level geography textbooks from the period 1900-1970 indicate environmental determinism as the prevailing theme, one which persisted in such texts for 20 years after it was abandoned as a central theme at university level. Researchers should have more contact with developers of secondary level materials. (Author/AV)

Chronic post-concussion neurocognitive deficits. II. Relationship with persistent symptoms

Directory of Open Access Journals (Sweden)

Jun eMaruta

2016-02-01

Full Text Available Individuals who sustain a concussion may continue to experience problems long after their injury. However, it has been postulated in the literature that the relationship between a concussive injury and persistent complaints attributed to it is mediated largely by the development of symptoms associated with posttraumatic stress disorder and depression. We sought to characterize cognitive deficits of adult patients who had persistent symptoms after a concussion and determine whether the original injury retains associations with these deficits after accounting for the developed symptoms that overlap with posttraumatic stress disorder and depression. We compared the results of neurocognitive testing from 33 patients of both genders aged 18-55 at three months to five years post-injury with those from 140 control subjects. Statistical comparisons revealed that patients generally produced accurate responses on reaction time-based tests, but with reduced efficiency. On visual tracking, patients increased gaze position error variability following an attention demanding task, an effect that may reflect greater fatigability. When neurocognitive performance was examined in the context of demographic- and symptom-related variables, the original injury retained associations with reduced performance at a statistically significant level. For some patients, reduced cognitive efficiency and fatigability may represent key elements of interference when interacting with the environment, leading to varied paths of recovery after a concussion. Poor recovery may be better understood when these deficits are taken into consideration.

A Roadmap Towards Intelligent and Autonomous Object Manipulation for assembly Tasks

DEFF Research Database (Denmark)

Polydoros, Athanasios; Nalpantidis, Lazaros; Krüger, Volker

Despite the large scientific interest on robot learning for object picking tasks, the research on object placing is too limited. Commonly, placing is simplistically considered as a trivial task, but real life manipulation problems indicate the exact opposite. A placing task can have different...

Mastering NServiceBus and persistence

CERN Document Server

Helton, Rich

2014-01-01

This book is intended for developers, designers, and architects alike who wish to build C# NServiceBus enterprise architectures and learn how ESB persists data and messages to help them attain their goals. No prior knowledge of persistence in NServiceBus is required.

Atypical subtrochanteric and diaphyseal femoral fractures: report of a task force of the American Society for Bone and Mineral Research

DEFF Research Database (Denmark)

Shane, Elizabeth; Burr, David; Ebeling, Peter R

2010-01-01

Reports linking long-term use of bisphosphonates (BPs) with atypical fractures of the femur led the leadership of the American Society for Bone and Mineral Research (ASBMR) to appoint a task force to address key questions related to this problem. A multidisciplinary expert group reviewed pertinent...... to designate a femoral fracture as atypical. Minor features include their association with cortical thickening, a periosteal reaction of the lateral cortex, prodromal pain, bilaterality, delayed healing, comorbid conditions, and concomitant drug exposures, including BPs, other antiresorptive agents...... published reports concerning atypical femur fractures, as well as preclinical studies that could provide insight into their pathogenesis. A case definition was developed so that subsequent studies report on the same condition. The task force defined major and minor features of complete and incomplete...

Survival Processing and the Stroop Task

Directory of Open Access Journals (Sweden)

Stephanie A. Kazanas

2015-11-01

Full Text Available This study was designed to investigate the impact of survival processing with a novel task for this paradigm: the Stroop color-naming task. As the literature is mixed with regard to task generalizability, with survival processing promoting better memory for words, but not better memory for faces or paired associates, these types of task investigations are important to a growing field of research. Using the Stroop task provides a unique contribution, as identifying items by color is an important evolutionary adaptation and not specific to humans as is the case with word recall. Our results indicate that survival processing, with its accompanying survival-relevance rating task, remains the best mnemonic strategy for word memory. However, our results also indicate that presenting the survival passage does not motivate better color-naming performance than color-naming alone. In addition, survival processing led to a larger amount of Stroop interference, though not significantly larger than the other conditions. Together, these findings suggest that considering one’s survival when performing memory and attention-based tasks does not enhance cognitive performance generally, although greater allocation of attentional resources to color-incongruent concrete objects could be considered adaptive. These findings support the notion that engaging in deeper processing via survival-relevance ratings may preserve these words across a variety of experimental manipulations.

The Performance of Children Prenatally Exposed to HIV on the A-Not-B Task in Kilifi, Kenya: A Preliminary Study

Directory of Open Access Journals (Sweden)

Charles. R. J. C. Newton

2013-09-01

Full Text Available The aim of the study was to investigate early executive functioning in young children from 6–35 months of age. The study involved 319 randomly selected children from the community, 17 HIV exposed but uninfected children and 31 HIV infected ARV-naive children. A variation of the A-not-B task was used. While there were no group differences in total correct, perseverative errors, nor maximum error run, a significant percentage of children were unable to complete the task as a consequence of the children becoming overtly distressed or refusing to continue. In a multivariate analysis we observed that the significant predictors of non-completion were HIV exposure (both infected and exposed and being under 24 months of age. These patterns of results indicate that future work with a broader array of tasks need to look at the association of HIV and EF tasks and potential contribution of factors such as emotion regulation, persistence and motivation on performance on EF tasks.

Clinical judgment research on economic topics: Role of congruence of tasks in clinical practice.

Science.gov (United States)

Huttin, Christine C

2017-01-01

This paper discusses what can ensure the performance of judgment studies with an information design that integrates economics of medical systems, in the context of digitalization of healthcare. It is part of a series of 5 methodological papers on statistical procedures and problems to implement judgment research designs and decision models, especially to address cost of care, and ways to measure conversation on cost of care between physicians and patients, with unstructured data such as economic narratives to complement billing and financial information (e.g. cost cognitive cues in conjoint or reversed conjoint designs). The paper discusses how congruence of tasks can increase the reliability of data. It uses some results of two Meta reviews of judgment studies in different fields of applications: psychology, business, medical sciences and education. It compares tests for congruence in judgment studies and efficiency tests in econometric studies.

Effect of pre-task music on sports or exercise performance.

Science.gov (United States)

Smirmaul, Bruno P

2017-01-01

Pre-task music is a very common strategy among sports competitors. However, as opposed to in-task music, the scientific evidence to support its ergogenic effects on either sports or exercise performance is limited. This brief review critically addresses the existing literature investigating the effects of pre-task music on sports and exercise performance, focusing on the methods and results of experimental studies, and offers basic and practical recommendations. In July 2015, a comprehensive literature search was performed in Web of Science, PubMed, and Google Scholar using the following key words in combination: "pre-task music," "pre-test music," "pre-exercise music," "exercise performance," "sports performance." The literature search was further expanded by both hand searching review articles on the topic and by searching the reference lists from the articles retrieved for any relevant references. Overall, a total of 15 studies in 14 articles were included. Pre-task music research has been unsystematic, methodologically limited and infrequent. Using this review as a starting point to overcome previous methodological limitations when designing future experiments may contribute to the development of pre-task music research, which is still in its infancy. Currently, there is no sufficient evidence to support the overall ergogenic effects of pre-task music on sports or exercise performance. Nonetheless, pre-task music has showed a likely ergogenic effect on shorter and predominantly anaerobic tasks such as grip strength, Wingate test, and short-duration sports or sports-like tasks, in contrast to longer and predominantly aerobic tasks.

An Online Cross-Sectional Comparison of Women With Symptoms of Persistent Genital Arousal, Painful Persistent Genital Arousal, and Chronic Vulvar Pain.

Science.gov (United States)

Jackowich, Robyn A; Pink, Leah; Gordon, Allan; Poirier, Évéline; Pukall, Caroline F

2018-04-01

Persistent genital arousal disorder (PGAD) is an understudied condition characterized by unwanted physiologic genital arousal in the absence of subjective sexual arousal. Markos and Dinsmore (Int J STD AIDS 2013;24:852-858) theorized that PGAD shares a number of similarities with vulvodynia (unexplained chronic vulvar pain [CVP]), including symptom characteristics and comorbidities. To compare medical histories, symptom characteristics, pain characteristics, and daily functioning among women with persistent genital pain (PGA) (n = 42), painful PGA (n = 37), and CVP (n = 42) symptoms. An online cross-sectional survey was conducted from October 2015 through April 2016. Self-report measures of symptoms, diagnosed medical conditions, pain characteristics (McGill Pain Questionnaire), catastrophizing (Pain Catastrophizing Scale), and daily functioning (Functional Status Questionnaire) were collected. All 3 groups reported similar medical diagnoses and high frequencies of other chronic pelvic pain conditions. Women in all 3 groups reported comparable ages at symptom onset and timing of symptom expression (ie, constant vs intermittent). Women in the 2 PGA groups reported significantly greater feelings of helplessness than women in the CVP group. Women in the painful PGA and CVP groups endorsed significantly more sensory terms to describe their symptoms compared with women in the PGA group, whereas women in the painful PGA group reported significantly more affective terms to describe their symptoms compared with women in the CVP group. Women in the 2 PGA groups reported that their symptoms interfered significantly with most areas of daily functioning. Given the similarities between PGA and CVP symptoms, women with PGA may benefit from similar assessment, treatment, and research approaches. Limitations of the present study include its sole use of self-report measures; the presence of PGA or CVP symptoms was not confirmed by clinical assessment. However, the anonymous

Long-term persistence of oral human papillomavirus type 16: the HPV Infection in Men (HIM) study.

Science.gov (United States)

Pierce Campbell, Christine M; Kreimer, Aimée R; Lin, Hui-Yi; Fulp, William; O'Keefe, Michael T; Ingles, Donna J; Abrahamsen, Martha; Villa, Luisa L; Lazcano-Ponce, Eduardo; Giuliano, Anna R

2015-03-01

Persistent infection with oral HPV16 is believed to drive the development of most oropharyngeal cancers. However, patterns of oral HPV16 persistence remain understudied, particularly among HIV-negative individuals. Oral HPV16 persistence was evaluated among 1,626 participants of the HPV Infection in Men (HIM) Study. Twenty-three oral HPV16-positive men who provided an oral gargle sample on ≥2 study visits were included in the analysis. Archived oral samples from all follow-up visits were tested for HPV16 using Linear Array and INNO-LiPA detection methods. Persistence was evaluated using consecutive HPV16-positive visits held approximately 6 months apart and using the Kaplan-Meier method. Oral HPV16-positive men were aged 18 to 64 years [median, 36 years; interquartile range (IQR), 25-42] and were followed for a median of 44.4 months (IQR, 29.9-49.5). Of 13 incident infections, 4 (30.8%) persisted ≥12 months, 1 (10.0%) persisted ≥24 months, and none persisted ≥36 months [median infection duration, 7.3 months; 95% confidence interval (CI), 6.4-NA)]. Of 10 prevalent infections, 9 (90.0%) persisted ≥12 months, 8 (80.0%) persisted ≥24 months, 4 (57.1%) persisted ≥36 months, and 2 (40.0%) persisted ≥48 months (median infection duration, NA). Twelve-month persistence of incident infections increased significantly with age (Ptrend = 0.028). Prevalent oral HPV16 infections in men persisted longer than newly acquired infections, and persistence appeared to increase with age. These findings may explain the high prevalence of oral HPV observed at older ages. Understanding oral HPV16 persistence will aid in the identification of men at high-risk of developing HPV-related oropharyngeal cancer. ©2015 American Association for Cancer Research.

University Experiences and Women Engineering Student Persistence

Science.gov (United States)

Ayers, LoAnn Debra Gienger

Riverside University (a pseudonym), like many universities, has not significantly increased the number of women who graduate with bachelor's degrees in engineering. The purpose of the study is to understand how the university experiences of women students influence the decision to persist in an undergraduate engineering degree and to understand the role of self-perception in how the students perceive experiences as supporting or hindering their persistence in the major. Archival data, documents and artifacts, observations, individual interviews, and a focus group with women engineering students provide insights into students' perceived barriers and supports of student success. Analysis of the data results in two major themes. First, students' self-confidence and self-efficacy influence how women assimilate university experiences as either supportive or diminishing of academic success. Second, university policies and practices shape the campus environment within which student experiences are formed and influence a student's level of institutional, academic, and social integration. The results of the study indicate opportunities for university leadership to enhance strategies that positively shape students' institutional, academic and social integration as precursors toward increasing the number of women students who successfully complete undergraduate engineering degrees at Riverside University. Future research is indicated to better understand how gender and gender identity intersects with other demographic factors, such as socio-economic status, immigration status, and life stage (e.g., traditional versus non-traditional students), to support or deter the persistence of engineering students to degree completion.

Quantitative analysis of task selection for brain-computer interfaces

Science.gov (United States)

Llera, Alberto; Gómez, Vicenç; Kappen, Hilbert J.

2014-10-01

Objective. To assess quantitatively the impact of task selection in the performance of brain-computer interfaces (BCI). Approach. We consider the task-pairs derived from multi-class BCI imagery movement tasks in three different datasets. We analyze for the first time the benefits of task selection on a large-scale basis (109 users) and evaluate the possibility of transferring task-pair information across days for a given subject. Main results. Selecting the subject-dependent optimal task-pair among three different imagery movement tasks results in approximately 20% potential increase in the number of users that can be expected to control a binary BCI. The improvement is observed with respect to the best task-pair fixed across subjects. The best task-pair selected for each subject individually during a first day of recordings is generally a good task-pair in subsequent days. In general, task learning from the user side has a positive influence in the generalization of the optimal task-pair, but special attention should be given to inexperienced subjects. Significance. These results add significant evidence to existing literature that advocates task selection as a necessary step towards usable BCIs. This contribution motivates further research focused on deriving adaptive methods for task selection on larger sets of mental tasks in practical online scenarios.

REINA at CLEF 2007 Robust Task

OpenAIRE

Zazo Rodríguez, Ángel Francisco; Figuerola, Carlos G.; Alonso Berrocal, José Luis

2007-01-01

This paper describes our work at CLEF 2007 Robust Task. We have participated in the monolingual (English, French and Portuguese) and the bilingual (English to French) subtask. At CLEF 2006 our research group obtained very good results applying local query expansion using windows of terms in the robust task. This year we have used the same expansion technique, but taking into account some criteria of robustness: MAP, GMAP, MMR, GS@10, P@10, number of failed topics, number of topics bellow 0.1 ...

Selective lesion of septal cholinergic neurons in rats impairs acquisition of a delayed matching to position T-maze task by delaying the shift from a response to a place strategy.

Science.gov (United States)

Fitz, Nicholas F; Gibbs, Robert B; Johnson, David A

2008-12-16

This study tested the hypothesis that septal cholinergic lesions impair acquisition of a delayed matching to position (DMP) T-maze task in male rats by affecting learning strategy. Rats received either the selective cholinergic immunotoxin, 192 IgG-saporin (SAP) or artificial cerebrospinal fluid directly into the medial septum. Two weeks later, animals were trained to acquire the DMP task. SAP-treated rats took significantly longer to acquire the task than corresponding controls. Both SAP-treated and control rats adopted a persistent turn and utilized a response strategy during early periods of training. By the time rats reached criterion the persistent turn was no longer evident, and all rats had shifted to an allocentric strategy, i.e., were relying on extramaze cues to a significant degree. During the acquisition period, SAP-treated rats spent significantly more days showing a persistent turn and using a response strategy than corresponding controls. The added time spent using a response strategy accounted entirely for the added days required to reach criterion among the SAP-treated rats. This suggests that the principal mechanism by which septal cholinergic lesions impair DMP acquisition in male rats is by increasing the predisposition to use a response vs. a place strategy, thereby affecting the ability to switch from one strategy to another.

Errors and conflict at the task level and the response level.

Science.gov (United States)

Desmet, Charlotte; Fias, Wim; Hartstra, Egbert; Brass, Marcel

2011-01-26

In the last decade, research on error and conflict processing has become one of the most influential research areas in the domain of cognitive control. There is now converging evidence that a specific part of the posterior frontomedian cortex (pFMC), the rostral cingulate zone (RCZ), is crucially involved in the processing of errors and conflict. However, error-related research has focused primarily on a specific error type, namely, response errors. The aim of the present study was to investigate whether errors on the task level rely on the same neural and functional mechanisms. Here we report a dissociation of both error types in the pFMC: whereas response errors activate the RCZ, task errors activate the dorsal frontomedian cortex. Although this last region shows an overlap in activation for task and response errors on the group level, a closer inspection of the single-subject data is more in accordance with a functional anatomical dissociation. When investigating brain areas related to conflict on the task and response levels, a clear dissociation was perceived between areas associated with response conflict and with task conflict. Overall, our data support a dissociation between response and task levels of processing in the pFMC. In addition, we provide additional evidence for a dissociation between conflict and errors both at the response level and at the task level.

Designing Prediction Tasks in a Mathematics Software Environment

Science.gov (United States)

Brunström, Mats; Fahlgren, Maria

2015-01-01

There is a recognised need in mathematics teaching for new kinds of tasks which exploit the affordances provided by new technology. This paper focuses on the design of prediction tasks to foster student reasoning about exponential functions in a mathematics software environment. It draws on the first iteration of a design based research study…

Generic cognitive adaptations to task interference in task switching

NARCIS (Netherlands)

Poljac, E.; Bekkering, H.

2009-01-01

The present study investigated how the activation of previous tasks interferes with the execution of future tasks as a result of temporal manipulations. Color and shape matching tasks were organized in runs of two trials each. The tasks were specified by a cue presented before a task run, cueing

Persistent Identifiers for Dutch cultural heritage institutions

Science.gov (United States)

Ras, Marcel; Kruithof, Gijsbert

2016-04-01

Over the past years, more and more collections belonging to archives, libraries, media, museums, and knowledge institutes are being digitised and made available online. These are exciting times for ALM institutions. They are realising that, in the information society, their collections are goldmines. Unfortunately most heritage institutions in the Netherlands do not yet meet the basic preconditions for long-term availability of their collections. The digital objects often have no long lasting fixed reference yet. URL's and web addresses change. Some digital objects that were referenced in Europeana and other portals can no longer be found. References in scientific articles have a very short life span, which is damaging for scholarly research. In 2015, the Dutch Digital Heritage Network (NDE) has started a two-year work program to co-ordinate existing initiatives in order to improve the (long-term) accessibility of the Dutch digital heritage for a wide range of users, anytime, anyplace. The Digital Heritage Network is a partnership established on the initiative of the Ministry of Education, Culture and Science. The members of the NDE are large, national institutions that strive to professionally preserve and manage digital data, e.g. the National Library, The Netherlands Institute for Sound and Vision, the Netherlands Cultural Heritage Agency, the Royal Netherlands Academy of Arts and Sciences, the National Archive of the Netherlands and the DEN Foundation, and a growing number of associations and individuals both within and outside the heritage sector. By means of three work programmes the goals of the Network should be accomplished and improve the visibility, the usability and the sustainability of digital heritage. Each programme contains of a set of projects. Within the sustainability program a project on creating a model for persistent identifiers is taking place. The main goals of the project are (1) raise awareness among cultural heritage institutions on the

Motivation, Intentionality, and Mind Wandering: Implications for Assessments of Task-Unrelated Thought

Science.gov (United States)

Seli, Paul; Cheyne, James Allan; Xu, Mengran; Purdon, Christine; Smilek, Daniel

2015-01-01

Researchers of mind wandering frequently assume that (a) participants are motivated to do well on the tasks they are given, and (b) task-unrelated thoughts (TUTs) that occur during task performance reflect unintentional, unwanted thoughts that occur despite participants' best intentions to maintain task-focus. Given the relatively boring and…

Drought Persistence Errors in Global Climate Models

Science.gov (United States)

Moon, H.; Gudmundsson, L.; Seneviratne, S. I.

2018-04-01

The persistence of drought events largely determines the severity of socioeconomic and ecological impacts, but the capability of current global climate models (GCMs) to simulate such events is subject to large uncertainties. In this study, the representation of drought persistence in GCMs is assessed by comparing state-of-the-art GCM model simulations to observation-based data sets. For doing so, we consider dry-to-dry transition probabilities at monthly and annual scales as estimates for drought persistence, where a dry status is defined as negative precipitation anomaly. Though there is a substantial spread in the drought persistence bias, most of the simulations show systematic underestimation of drought persistence at global scale. Subsequently, we analyzed to which degree (i) inaccurate observations, (ii) differences among models, (iii) internal climate variability, and (iv) uncertainty of the employed statistical methods contribute to the spread in drought persistence errors using an analysis of variance approach. The results show that at monthly scale, model uncertainty and observational uncertainty dominate, while the contribution from internal variability is small in most cases. At annual scale, the spread of the drought persistence error is dominated by the statistical estimation error of drought persistence, indicating that the partitioning of the error is impaired by the limited number of considered time steps. These findings reveal systematic errors in the representation of drought persistence in current GCMs and suggest directions for further model improvement.

Sleep deprivation and time-on-task performance decrement in the rat psychomotor vigilance task.

Science.gov (United States)

Oonk, Marcella; Davis, Christopher J; Krueger, James M; Wisor, Jonathan P; Van Dongen, Hans P A

2015-03-01

The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. The study was conducted in an academic research vivarium. Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. The rPVT manifests similarities to the hPVT in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. © 2015 Associated Professional Sleep Societies, LLC.

DECOVALEX II PROJECT. Technical report - Task 1A and 1B

International Nuclear Information System (INIS)

Lanru Jing; Stephansson, Ove; Kautsky, F.

1998-08-01

DECOVALEX II project started in November 1995 as a continuation of the DECOVALEX I project, which was completed at the end of 1994. The project was initiated by recognizing the fact that a proper evaluation of the current capacities of numerical modelling of the coupled T-H-M processes in fractured media is needed not only for small scale, well controlled laboratory test cases such as those studied in DECOVALEX I, but also for less characterised, more complex and realistic in-situ experiments. This will contribute to validation and confidence building in the current mathematical models, numerical methods and computer codes. Four tasks were defined in the DECOVALEX II project: TASK 1 - numerical study of the RCF3 pumping test and shaft excavation at Sellafield by Nirex, UK; TASK 2 - numerical study of the in-situ T-H-M experiments at Kamaishi Mine by PNC, Japan; TASK 3 - review of current state-of-the-art of rock joint research and TASK 4 - report on the coupled T-H-M issues related to repository design and performance assessment. This report is one of the technical reports of the DECOVALEX II project, describing the work performed for TASK 1A and 1B - the predictions and model calibrations for the RCF 3 pumping test at Sellafield. Presented in this report are the descriptions of the project, tasks, approaches, methods and results of numerical modelling work carried out by the research teams. The report is a summary of the research reports written by the research teams and submitted to the project secretariat, and the discussions held during project workshops and task force group meetings. The opinions and conclusions in this report, however, reflect only ideas of the authors, not necessarily a collective representation of the funding organisations of the project

Differential wolf-pack-size persistence and the role of risk when hunting dangerous prey

Science.gov (United States)

Barber-Meyer, Shannon M.; Mech, L. David; Newton, Wesley E.; Borg, Bridget

2016-01-01

Risk to predators hunting dangerous prey is an emerging area of research and could account for possible persistent differences in gray wolf (Canis lupus) pack sizes. We documented significant differences in long-term wolf-pack-size averages and variation in the Superior National Forest (SNF), Denali National Park and Preserve, Yellowstone National Park, and Yukon, Canada (pwolves’ risk when hunting primary prey, for those packs (N=3) hunting moose (Alces americanus) were significantly larger than those (N=10) hunting white-tailed deer (Odocoileus virginianus) (F1,8=16.50, p=0.004). Our data support the hypothesis that differential pack-size persistence may be perpetuated by differences in primary prey riskiness to wolves, and we highlight two important extensions of this idea: (1) the potential for wolves to provision and defend injured packmates from other wolves and (2) the importance of less-risky, buffer prey to pack-size persistence and year-to-year variation. Risk to predators hunting dangerous prey is an emerging area of research and could account for possible persistent differences in gray wolf (Canis lupus) pack sizes. We documented significant differences in long-term wolf-pack-size averages and variation in the Superior National Forest (SNF), Denali National Park and Preserve, Yellowstone National Park, and Yukon, Canada (pwolves’ risk when hunting primary prey, for those packs (N=3) hunting moose (Alces americanus) were significantly larger than those (N=10) hunting white-tailed deer (Odocoileus virginianus) (F1,8=16.50, p=0.004). Our data support the hypothesis that differential pack-size persistence may be perpetuated by differences in primary prey riskiness to wolves, and we highlight two important extensions of this idea: (1) the potential for wolves to provision and defend injured packmates from other wolves and (2) the importance of less-risky, buffer prey to pack-size persistence and year-to-year variation.

"It's More Flexible": Persistence of Women Engineers in the Academy

Science.gov (United States)

Mlambo, Yeukai Angela; Mabokela, Reitumetse Obakeng

2017-01-01

The under-representation of women in engineering is an issue of concern for policy-makers. While much of the existing literature has focussed on understanding reasons for women's under-representation in engineering and related technical fields, there is a paucity of research that examines why women who are already in engineering persist. This…

Working Memory Training Improves Dual-Task Performance on Motor Tasks.

Science.gov (United States)

Kimura, Takehide; Kaneko, Fuminari; Nagahata, Keita; Shibata, Eriko; Aoki, Nobuhiro

2017-01-01

The authors investigated whether working memory training improves motor-motor dual-task performance consisted of upper and lower limb tasks. The upper limb task was a simple reaction task and the lower limb task was an isometric knee extension task. 45 participants (age = 21.8 ± 1.6 years) were classified into a working memory training group (WM-TRG), dual-task training group, or control group. The training duration was 2 weeks (15 min, 4 times/week). Our results indicated that working memory capacity increased significantly only in the WM-TRG. Dual-task performance improved in the WM-TRG and dual-task training group. Our study provides the novel insight that working memory training improves dual-task performance without specific training on the target motor task.

Stochastic convergence of persistence landscapes and silhouettes

Directory of Open Access Journals (Sweden)

Frédéric Chazal

2015-03-01

Full Text Available Persistent homology is a widely used tool in Topological Data Analysis that encodes multi-scale topological information as a multiset of points in the plane called a persistence diagram. It is difficult to apply statistical theory directly to a random sample of diagrams. Instead, we summarize persistent homology with a persistence landscape, introduced by Bubenik, which converts a diagram into a well-behaved real-valued function. We investigate the statistical properties of landscapes, such as weak convergence of the average landscapes and convergence of the bootstrap. In addition, we introduce an alternate functional summary of persistent homology, which we call the silhouette, and derive an analogous statistical theory.

An FMRI-compatible Symbol Search task.

Science.gov (United States)

Liebel, Spencer W; Clark, Uraina S; Xu, Xiaomeng; Riskin-Jones, Hannah H; Hawkshead, Brittany E; Schwarz, Nicolette F; Labbe, Donald; Jerskey, Beth A; Sweet, Lawrence H

2015-03-01

Our objective was to determine whether a Symbol Search paradigm developed for functional magnetic resonance imaging (FMRI) is a reliable and valid measure of cognitive processing speed (CPS) in healthy older adults. As all older adults are expected to experience cognitive declines due to aging, and CPS is one of the domains most affected by age, establishing a reliable and valid measure of CPS that can be administered inside an MR scanner may prove invaluable in future clinical and research settings. We evaluated the reliability and construct validity of a newly developed FMRI Symbol Search task by comparing participants' performance in and outside of the scanner and to the widely used and standardized Symbol Search subtest of the Wechsler Adult Intelligence Scale (WAIS). A brief battery of neuropsychological measures was also administered to assess the convergent and discriminant validity of the FMRI Symbol Search task. The FMRI Symbol Search task demonstrated high test-retest reliability when compared to performance on the same task administered out of the scanner (r=.791; pSymbol Search (r=.717; pSymbol Search task were also observed. The FMRI Symbol Search task is a reliable and valid measure of CPS in healthy older adults and exhibits expected sensitivity to the effects of age on CPS performance.

Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease

Directory of Open Access Journals (Sweden)

Marianne J. Middelveen

2018-04-01

Full Text Available Introduction: Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borrelia burgdorferi, in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. Methods: In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of ten control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. Results: Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borrelia burgdorferi by three distinct polymerase chain reaction (PCR-based approaches. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. Conclusions: Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.

Persistence of Latino Students in Community Colleges: An Empowerment Model Addressing Acculturative Stress

Science.gov (United States)

Wilson, Judy C.

2012-01-01

College student persistence has been a concern of researchers and practitioners since the early 1960s. Traditional models have addressed the need for students to be integrated into the academic and social domains of the college campus. Recently, critical theorists and researchers have been questioning the relevance of the traditional models for…

Missed diagnosis-persistent delirium

Directory of Open Access Journals (Sweden)

Aseem Mehra

2014-01-01

Full Text Available Delirium is in general considered as an acute short lasting reversible neuropsychiatric syndrome. However, there is some evidence to suggest that in a small proportion of cases delirium may be a chronic or persistent condition. However, making this diagnosis requires clinical suspicion and ruling other differential diagnosis. In this report, we present a case of a 55-year-old man who had cognitive symptoms, psychotic symptoms and depressive symptoms along with persistent hypokalemia and glucose intolerance. He was seen by 3 psychiatrists with these symptoms and was initially diagnosed as having depressive disorder and later diagnosis of bipolar affective disorder (current episode mania, and psychosis were considered by the third psychiatrist. However, despite the presence of persistent neurocognitive deficits, evening worsening of symptoms, hypokalemia and glucose intolerance diagnosis of delirium was not suspected.

Poor fine-motor and visuospatial skills predict persistence of pediatric-onset obsessive-compulsive disorder into adulthood.

Science.gov (United States)

Bloch, Michael H; Sukhodolsky, Denis G; Dombrowski, Philip A; Panza, Kaitlyn E; Craiglow, Brittany G; Landeros-Weisenberger, Angeli; Leckman, James F; Peterson, Bradley S; Schultz, Robert T

2011-09-01

Half of pediatric-onset OCD cases remit by adulthood. Studies have demonstrated that initial response to pharmacotherapy, age of onset, prominent hoarding symptoms, and the presence of comorbid tic disorders are associated with long-term outcome. Our goal was to examine the association between childhood performance on neuropsychological testing and persistence of OCD into adulthood. Twenty-four children with OCD were followed for an average of 7.5 years into early adulthood. Neuropsychological performance in childhood (childhood performance on the Purdue pegboard task and the block design subscale of WISC-III was associated with persistence of OCD symptoms into adulthood. IQ, VMI, and nonverbal memory performance did not predict significantly the persistence of OCD. These results suggest that visuospatial and fine-motor skill deficits are predictive of poor long-term outcome in pediatric-onset OCD. Future longitudinal studies are needed to chart the course of these deficits relative to the course of symptoms in OCD and to determine whether the association of these neuropsychiatric deficits with long-term outcome is specific to pediatric-onset OCD or generalizes to other psychiatric disorders. © 2011 The Authors. Journal of Child Psychology and Psychiatry © 2011 Association for Child and Adolescent Mental Health.

The Attentional Dependence of Emotion Cognition is Variable with the Competing Task

Directory of Open Access Journals (Sweden)

Cheng Chen

2016-11-01

Full Text Available The relationship between emotion and attention has fascinated researchers for decades. Many previous studies have used eye-tracking, ERP, MEG and fMRI to explore this issue but have reached different conclusions: some researchers hold that emotion cognition is an automatic process and independent of attention, while some others believed that emotion cognition is modulated by attentional resources and is a type of controlled processing. The present research aimed to investigate this controversy, and we hypothesized that the attentional dependence of emotion cognition is variable with the competing task. Eye-tracking technology and a dual-task paradigm were adopted, and subjects’ attention was manipulated to fixate at the central task to investigate whether subjects could detect the emotional faces presented in the peripheral area with a decrease or near-absence of attention. The results revealed that when the peripheral task was emotional face discrimination but the central attention-demanding task was different, subjects performed well in the peripheral task, which means that emotional information can be processed in parallel with other stimuli, and there may be a specific channel in the human brain for processing emotional information. However, when the central and peripheral tasks were both emotional face discrimination, subjects could not perform well in the peripheral task, indicating that the processing of emotional information required attentional resources and that it is a type of controlled processing. Therefore, we concluded that the attentional dependence of emotion cognition varied with the competing task.

Global estimation of long-term persistence in annual river runoff

Science.gov (United States)

Markonis, Y.; Moustakis, Y.; Nasika, C.; Sychova, P.; Dimitriadis, P.; Hanel, M.; Máca, P.; Papalexiou, S. M.

2018-03-01

Long-term persistence (LTP) of annual river runoff is a topic of ongoing hydrological research, due to its implications to water resources management. Here, we estimate its strength, measured by the Hurst coefficient H, in 696 annual, globally distributed, streamflow records with at least 80 years of data. We use three estimation methods (maximum likelihood estimator, Whittle estimator and least squares variance) resulting in similar mean values of H close to 0.65. Subsequently, we explore potential factors influencing H by two linear (Spearman's rank correlation, multiple linear regression) and two non-linear (self-organizing maps, random forests) techniques. Catchment area is found to be crucial for medium to larger watersheds, while climatic controls, such as aridity index, have higher impact to smaller ones. Our findings indicate that long-term persistence is weaker than found in other studies, suggesting that enhanced LTP is encountered in large-catchment rivers, were the effect of spatial aggregation is more intense. However, we also show that the estimated values of H can be reproduced by a short-term persistence stochastic model such as an auto-regressive AR(1) process. A direct consequence is that some of the most common methods for the estimation of H coefficient, might not be suitable for discriminating short- and long-term persistence even in long observational records.

Bacterial persistence

Indian Academy of Sciences (India)

PRAKASH KUMAR

Drug indifference versus persistence. Studies on the mode of ... is a special case of drug indifference, restricted to a small ... to his model (outlined in detail in Lewis 2008), treatment .... belong to the heat and cold shock response family; many.

Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit

Science.gov (United States)

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms.…

Task analysis methods applicable to control room design review (CDR)

International Nuclear Information System (INIS)

Moray, N.P.; Senders, J.W.; Rhodes, W.

1985-06-01

This report presents the results of a research study conducted in support of the human factors engineering program of the Atomic Energy Control Board in Canada. It contains five products which may be used by the Atomic Enegy Control Board in relation to Task Analysis of jobs in CANDU nuclear power plants: 1. a detailed method for preparing for a task analysis; 2. a Task Data Form for recording task analysis data; 3. a detailed method for carrying out task analyses; 4. a guide to assessing alternative methods for performing task analyses, if such are proposed by utilities or consultants; and 5. an annotated bibliography on task analysis. In addition, a short explanation of the origins, nature and uses of task analysis is provided, with some examples of its cost effectiveness. 35 refs

Subjective cognitive impairment: functional MRI during a divided attention task.

Science.gov (United States)

Rodda, J; Dannhauser, T; Cutinha, D J; Shergill, S S; Walker, Z

2011-10-01

Individuals with subjective cognitive impairment (SCI) have persistent memory complaints but normal neurocognitive performance. For some, this may represent a pre-mild cognitive impairment (MCI) stage of Alzheimer's disease (AD). Given that attentional deficits and associated brain activation changes are present early in the course of AD, we aimed to determine whether SCI is associated with brain activation changes during attentional processing. Eleven SCI subjects and 10 controls completed a divided attention task during functional magnetic resonance imaging. SCI and control groups did not differ in sociodemographic, neurocognitive or behavioural measures. When group activation during the divided attention task was compared, the SCI group demonstrated increased activation in left medial temporal lobe, bilateral thalamus, posterior cingulate and caudate. This pattern of increased activation is similar to the pattern of decreased activation reported during divided attention in AD and may indicate compensatory changes. These findings suggest the presence of early functional changes in SCI; longitudinal studies will help to further elucidate the relationship between SCI and AD. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Task difficulty, risk, effort and comfort in a simulated driving task--Implications for Risk Allostasis Theory.

Science.gov (United States)

Lewis-Evans, Ben; Rothengatter, Talib

2009-09-01

Risk Allostasis Theory states that drivers seek to maintain a feeling of risk within a preferred range [Fuller, R., 2008. What drives the driver? Surface tensions and hidden consensus. In: Keynote at the 4th International Conference on Traffic and Transport Psychology, Washington, DC, August 31-September 4, 2008]. Risk Allostasis Theory is the latest version of Task-Difficulty Homeostasis theory, and is in part based on the findings of experiments where participants were asked to rate the task difficulty, feeling of risk and chance of collision of scenes shown in digitally altered video clips [Fuller, R., McHugh, C., Pender, S., 2008b. Task difficulty and risk in the determination of driver behaviour. Revue européenne de psychologie appliqée 58, 13-21]. The focus of the current research was to expand upon the previous video based experiments using a driving simulator. This allowed participants to be in control of the vehicle rather than acting as passive observers, as well as providing additional speed cues. The results support previous findings that ratings of task difficulty and feeling of risk are related, and that they are also highly related to ratings of effort and moderately related to ratings of comfort and habit. However, the linearly increasing trend for task difficulty and feeling of risk described by the previous research was not observed: instead the findings of this experiment support a threshold effect where ratings of risk (feeling of and chance of loss of control/collision), difficulty, effort, and comfort go through a period of stability and only start to increase once a certain threshold has been crossed. It is within the period of stability where subjective experience of risk and difficulty is low, or absent, that drivers generally prefer to operate.

Effects of a Tailored Incredible Years Teacher Classroom Management Programme on On-Task Behaviour of School Children with ADHD in Addis Ababa

Science.gov (United States)

Mohammed, Feruz

2018-01-01

Attention-Deficit/Hyperactivity Disorder (ADHD) is a persistent pattern of behaviours characterized by inattention, hyperactivity and impulsivity. This study evaluates the effects of a tailored Incredible Years Teacher Classroom Management (IYTCM) programme aimed to improve participating children's on-task behaviour in a group of 6 to 10 year old…

Ranking of persister genes in the same Escherichia coli genetic background demonstrates varying importance of individual persister genes in tolerance to different antibiotics

Directory of Open Access Journals (Sweden)

Nan eWu

2015-09-01

Full Text Available Despite the identification of many genes and pathways involved in the persistence phenomenon of bacteria, the relative importance of these genes in a single organism remains unclear. Here, using Escherichia coli as a model, we generated mutants of 21 known candidate persister genes and compared the relative importance of these mutants in persistence to various antibiotics (ampicillin, gentamicin, norfloxacin, and trimethoprim at different times. We found that oxyR, dnaK, sucB, relA, rpoS, clpB, mqsR, and recA were prominent persister genes involved in persistence to multiple antibiotics. These genes map to the following pathways: antioxidative defense pathway (oxyR, global regulators (dnaK, clpB, and rpoS, energy production (sucB, stringent response (relA, toxin–antitoxin (TA module (mqsR, and SOS response (recA. Among the TA modules, the ranking order was mqsR, lon, relE, tisAB, hipA, and dinJ. Intriguingly, rpoS deletion caused a defect in persistence to gentamicin but increased persistence to ampicillin and norfloxacin. Mutants demonstrated dramatic differences in persistence to different antibiotics at different time points: some mutants (oxyR, dnaK, phoU, lon, recA, mqsR, and tisAB displayed defect in persistence from early time points, while other mutants (relE, smpB, glpD, umuD, and tnaA showed defect only at later time points. These results indicate that varying hierarchy and importance of persister genes exist and that persister genes can be divided into those involved in shallow persistence and those involved in deep persistence. Our findings suggest that the persistence phenomenon is a dynamic process with different persister genes playing roles of variable significance at different times. These findings have implications for improved understanding of persistence phenomenon and developing new drugs targeting persisters for more effective cure of persistent infections.

The Effect of MALL-Based Tasks on EFL Learners' Grammar Learning

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Khodabandeh, Farzaneh; Alian, Jalal ed-din; Soleimani, Hassan

2017-01-01

Many studies have confirmed the importance of tasks on language learning. Nowadays, many teachers apply different kinds of tasks in their classrooms. The current study investigated the effect of mobile assisted language learning tasks (MALL) on participants' English grammar learning. The researcher administered a pre-validated grammar test to 90…

Creation of the Naturalistic Engagement in Secondary Tasks (NEST) distracted driving dataset.

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Owens, Justin M; Angell, Linda; Hankey, Jonathan M; Foley, James; Ebe, Kazutoshi

2015-09-01

Distracted driving has become a topic of critical importance to driving safety research over the past several decades. Naturalistic driving data offer a unique opportunity to study how drivers engage with secondary tasks in real-world driving; however, the complexities involved with identifying and coding relevant epochs of naturalistic data have limited its accessibility to the general research community. This project was developed to help address this problem by creating an accessible dataset of driver behavior and situational factors observed during distraction-related safety-critical events and baseline driving epochs, using the Strategic Highway Research Program 2 (SHRP2) naturalistic dataset. The new NEST (Naturalistic Engagement in Secondary Tasks) dataset was created using crashes and near-crashes from the SHRP2 dataset that were identified as including secondary task engagement as a potential contributing factor. Data coding included frame-by-frame video analysis of secondary task and hands-on-wheel activity, as well as summary event information. In addition, information about each secondary task engagement within the trip prior to the crash/near-crash was coded at a higher level. Data were also coded for four baseline epochs and trips per safety-critical event. 1,180 events and baseline epochs were coded, and a dataset was constructed. The project team is currently working to determine the most useful way to allow broad public access to the dataset. We anticipate that the NEST dataset will be extraordinarily useful in allowing qualified researchers access to timely, real-world data concerning how drivers interact with secondary tasks during safety-critical events and baseline driving. The coded dataset developed for this project will allow future researchers to have access to detailed data on driver secondary task engagement in the real world. It will be useful for standalone research, as well as for integration with additional SHRP2 data to enable the

Detecting gait abnormalities after concussion or mild traumatic brain injury: A systematic review of single-task, dual-task, and complex gait.

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Fino, Peter C; Parrington, Lucy; Pitt, Will; Martini, Douglas N; Chesnutt, James C; Chou, Li-Shan; King, Laurie A

2018-05-01

While a growing number of studies have investigated the effects of concussion or mild traumatic brain injury (mTBI) on gait, many studies use different experimental paradigms and outcome measures. The path for translating experimental studies for objective clinical assessments of gait is unclear. This review asked 2 questions: 1) is gait abnormal after concussion/mTBI, and 2) what gait paradigms (single-task, dual-task, complex gait) detect abnormalities after concussion. Data sources included MEDLINE/PubMed, Scopus, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) accessed on March 14, 2017. Original research articles reporting gait outcomes in people with concussion or mTBI were included. Studies of moderate, severe, or unspecified TBI, and studies without a comparator were excluded. After screening 233 articles, 38 studies were included and assigned to one or more sections based on the protocol and reported outcomes. Twenty-six articles reported single-task simple gait outcomes, 24 reported dual-task simple gait outcomes, 21 reported single-task complex gait outcomes, and 10 reported dual-task complex gait outcomes. Overall, this review provides evidence for two conclusions: 1) gait is abnormal acutely after concussion/mTBI but generally resolves over time; and 2) the inconsistency of findings, small sample sizes, and small number of studies examining homogenous measures at the same time-period post-concussion highlight the need for replication across independent populations and investigators. Future research should concentrate on dual-task and complex gait tasks, as they showed promise for detecting abnormal locomotor function outside of the acute timeframe. Additionally, studies should provide detailed demographic and clinical characteristics to enable more refined comparisons across studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Sort-Mid tasks scheduling algorithm in grid computing.

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Reda, Naglaa M; Tawfik, A; Marzok, Mohamed A; Khamis, Soheir M

2015-11-01

Scheduling tasks on heterogeneous resources distributed over a grid computing system is an NP-complete problem. The main aim for several researchers is to develop variant scheduling algorithms for achieving optimality, and they have shown a good performance for tasks scheduling regarding resources selection. However, using of the full power of resources is still a challenge. In this paper, a new heuristic algorithm called Sort-Mid is proposed. It aims to maximizing the utilization and minimizing the makespan. The new strategy of Sort-Mid algorithm is to find appropriate resources. The base step is to get the average value via sorting list of completion time of each task. Then, the maximum average is obtained. Finally, the task has the maximum average is allocated to the machine that has the minimum completion time. The allocated task is deleted and then, these steps are repeated until all tasks are allocated. Experimental tests show that the proposed algorithm outperforms almost other algorithms in terms of resources utilization and makespan.

Tasks of physicists and graduated engineers in diagnostic radiology

International Nuclear Information System (INIS)

Angerstein, W.

1987-01-01

The tasks of physicists and engineers in diagnostic radiology are compiled and trends of development are discussed. Specific duties can be selected from these tasks for each department and physicist individually. An attempt is made to characterize the specific tasks of medical physics. The most important tasks are concerning subjects of (1) investment planning, (2) quality control and quality assurance, (3) service and maintenance, (4) radiation protection and electrical safety, (5) development, testing and adaption of equipment, (6) assistance in running the radiologic department, (7) research, (8) pre- and postgraduate training, (9) educational training, (10) miscellaneous. (author)

Task-set inertia and memory-consolidation bottleneck in dual tasks.

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Koch, Iring; Rumiati, Raffaella I

2006-11-01

Three dual-task experiments examined the influence of processing a briefly presented visual object for deferred verbal report on performance in an unrelated auditory-manual reaction time (RT) task. RT was increased at short stimulus-onset asynchronies (SOAs) relative to long SOAs, showing that memory consolidation processes can produce a functional processing bottleneck in dual-task performance. In addition, the experiments manipulated the spatial compatibility of the orientation of the visual object and the side of the speeded manual response. This cross-task compatibility produced relative RT benefits only when the instruction for the visual task emphasized overlap at the level of response codes across the task sets (Experiment 1). However, once the effective task set was in place, it continued to produce cross-task compatibility effects even in single-task situations ("ignore" trials in Experiment 2) and when instructions for the visual task did not explicitly require spatial coding of object orientation (Experiment 3). Taken together, the data suggest a considerable degree of task-set inertia in dual-task performance, which is also reinforced by finding costs of switching task sequences (e.g., AC --> BC vs. BC --> BC) in Experiment 3.

Reaping the benefits of task conflict in teams: the critical role of team psychological safety climate.