WorldWideScience

Sample records for learning defects role

  1. BENCHMARKING MACHINE LEARNING TECHNIQUES FOR SOFTWARE DEFECT DETECTION

    OpenAIRE

    Saiqa Aleem; Luiz Fernando Capretz; Faheem Ahmed

    2015-01-01

    Machine Learning approaches are good in solving problems that have less information. In most cases, the software domain problems characterize as a process of learning that depend on the various circumstances and changes accordingly. A predictive model is constructed by using machine learning approaches and classified them into defective and non-defective modules. Machine learning techniques help developers to retrieve useful information after the classification and enable them to analyse data...

  2. Impurity Role In Mechanically Induced Defects

    International Nuclear Information System (INIS)

    Howell, R.H.; Asoka-Kumar, P.; Hartley, J.; Sterne, P.

    2000-01-01

    An improved understanding of dislocation dynamics and interactions is an outstanding problem in the multi scale modeling of materials properties, and is the current focus of major theoretical efforts world wide. We have developed experimental and theoretical tools that will enable us to measure and calculate quantities defined by the defect structure. Unique to the measurements is a new spectroscopy that determines the detailed elemental composition at the defect site. The measurements are based on positron annihilation spectroscopy performed with a 3 MeV positron beam [1]. Positron annihilation spectroscopy is highly sensitive to dislocations and associated defects and can provide unique elements of the defect size and structure. Performing this spectroscopy with a highly penetrating positron beam enables flexibility in sample handling. Experiments on fatigued and stressed samples have been done and in situ measurement capabilities have been developed. We have recently performed significant upgrades to the accelerator operation and novel new experiments have been performed [2-4] To relate the spectrographic results and the detailed structure of a defect requires detailed calculations. Measurements are coupled with calculated results based on a description of positions of atoms at the defect. This gives an atomistic view of dislocations and associated defects including impurity interactions. Our ability to probe impurity interactions is a unique contribution to defect understanding not easily addressed by other atomistic spectroscopies

  3. Cycles of cooperation and defection in imperfect learning

    International Nuclear Information System (INIS)

    Galla, Tobias

    2011-01-01

    We investigate a model of learning the iterated prisoner's dilemma game. Players have the choice between three strategies: always defect (ALLD), always cooperate (ALLC) and tit-for-tat (TFT). The only strict Nash equilibrium in this situation is ALLD. When players learn to play this game convergence to the equilibrium is not guaranteed, for example we find cooperative behaviour if players discount observations in the distant past. When agents use small samples of observed moves to estimate their opponent's strategy the learning process is stochastic, and sustained oscillations between cooperation and defection can emerge. These cycles are similar to those found in stochastic evolutionary processes, but the origin of the noise sustaining the oscillations is different and lies in the imperfect sampling of the opponent's strategy. Based on a systematic expansion technique, we are able to predict the properties of these learning cycles, providing an analytical tool with which the outcome of more general stochastic adaptation processes can be characterised

  4. Management of segmental bony defects: the role of osteoconductive orthobiologics.

    Science.gov (United States)

    McKee, Michael D

    2006-01-01

    Our knowledge about, and the availability of, orthobiologic materials has increased exponentially in the last decade. Although previously confined to the experimental or animal-model realm, several orthobiologics have been shown to be useful in a variety of clinical situations. As surgical techniques in vascular anastomosis, soft-tissue coverage, limb salvage, and fracture stabilization have improved, the size and frequency of bony defects (commensurate with the severity of the initial injury) have increased, as well. Because all methods of managing segmental bony defects have drawbacks, a need remains for a readily available, void-filling, inexpensive bone substitute. Such a bone substitute fulfills a permissive role in allowing new bone to grow into a given defect. Such potential osteoconductive materials include ceramics, calcium sulfate or calcium phosphate compounds, hydroxyapatite, deproteinized bone, corals, and recently developed polymers. Some materials that have osteoinductive properties, such as demineralized bone matrix, also display prominent osteoconductive properties.

  5. ROLE OF DATA MINING CLASSIFICATION TECHNIQUE IN SOFTWARE DEFECT PREDICTION

    OpenAIRE

    Dr.A.R.Pon Periyasamy; Mrs A.Misbahulhuda

    2017-01-01

    Software defect prediction is the process of locating defective modules in software. Software quality may be a field of study and apply that describes the fascinating attributes of software package product. The performance should be excellent with none defects. Software quality metrics are a set of software package metrics that target the standard aspects of the product, process, and project. The software package defect prediction model helps in early detection of defects and contributes to t...

  6. The role of defects in laser damage of multilayer coatings

    International Nuclear Information System (INIS)

    Kozlowski, M.R.; Chow, R.

    1993-01-01

    Laser induced damage to optical coatings is generally a localized phenomenon associated with coating defects. The most common of the defect types are the well-known nodule defect. This paper reviews the use of experiments and modeling to understand the formation of these defects and their interaction with laser light. Of particular interest are efforts to identify which defects are most susceptible to laser damage. Also discussed are possible methods for stabilizing these defects (laser conditioning) or preventing their initiation (source stabilization, spatter particle trapping)

  7. Breakdown, fractoemission, diffusion: role of defects in dielectrics

    International Nuclear Information System (INIS)

    Vigouroux, J.P.; Serruys, Y.

    1987-01-01

    During the surface analysis of dielectric materials, the impinging ionising particles induce point defects localised in the band gap and build an electrical charge. The electric field created by the charged defects modifies the physico-chemical properties of surface and bulk. We show that the fundamental study of defects allows a better understanding of technological phenomena such as dielectric breakdown, fracture and diffusion [fr

  8. Kinesthetic Role in Motorist Learning

    OpenAIRE

    Mukhlisin, Mukhlisin; Rahmawati, Lilis

    2016-01-01

    This article describes the role of kinesthetic in motor learning. It starts with a definition that kinesthetic is Generally regarded as "a feeling or awareness" of body position and body movement. But there are four factors are seemingly quite common in definitions of kinesthetic: positioning of body segments, precision of movement, balance, and spatial orientation. Any Appropriate reference explaining the reception and transmission of kinesthetic information during movement has not yet been ...

  9. The role of point defects and defect complexes in silicon device processing. Summary report and papers

    Energy Technology Data Exchange (ETDEWEB)

    Sopori, B.; Tan, T.Y.

    1994-08-01

    This report is a summary of a workshop hold on August 24--26, 1992. Session 1 of the conference discussed characteristics of various commercial photovoltaic silicon substrates, the nature of impurities and defects in them, and how they are related to the material growth. Session 2 on point defects reviewed the capabilities of theoretical approaches to determine equilibrium structure of defects in the silicon lattice arising from transitional metal impurities and hydrogen. Session 3 was devoted to a discussion of the surface photovoltaic method for characterizing bulk wafer lifetimes, and to detailed studies on the effectiveness of various gettering operations on reducing the deleterious effects of transition metals. Papers presented at the conference are also included in this summary report.

  10. The role of defects and doping in 2D graphene sheets and 1D nanoribbons.

    Science.gov (United States)

    Terrones, Humberto; Lv, Ruitao; Terrones, Mauricio; Dresselhaus, Mildred S

    2012-06-01

    Defects are usually seen as imperfections in materials that could significantly degrade their performance. However, at the nanoscale, defects could be extremely useful since they could be exploited to generate novel, innovative and useful materials and devices. Graphene and graphene nanoribbons are no exception. This review therefore tries to categorize defects, emphasize their importance, introduce the common routes to study and identify them and to propose new ways to construct novel devices based on 'defective' graphene-like materials. In particular, we will discuss defects in graphene-like systems including (a) structural (sp(2)-like) defects, (b) topological (sp(2)-like) defects, (c) doping or functionalization (sp(2)- and sp(3)-like) defects and (d) vacancies/edge type defects (non-sp(2)-like). It will be demonstrated that defects play a key role in graphene physicochemical properties and could even be critical to generate biocompatible materials. There are numerous challenges in this emerging field, and we intend to provide a stimulating account which could trigger new science and technological developments based on defective graphene-like materials that could be introduced into other atomic layered materials, such as BN, MoS(2) and WS(2), not discussed in this review.

  11. Entropy Crisis, Defects and the Role of Competition in Monatomic Glass Formers

    OpenAIRE

    Gujrati, P. D.

    2007-01-01

    We establish the existence of an entropy crisis in monatomic glass formers. The work finally shows that the entropy crisis is ubiqutous in all supercooled liquids. We also study the roles of defects and energetic competition on the ideal glass.

  12. Fatigue crack initiation – The role of point defects

    Czech Academy of Sciences Publication Activity Database

    Polák, Jaroslav; Man, Jiří

    2014-01-01

    Roč. 65, AUG (2014), s. 18-27 ISSN 0142-1123 R&D Projects: GA ČR(CZ) GAP108/10/2371; GA ČR(CZ) GA13-23652S Institutional support: RVO:68081723 Keywords : Fatigue crack initiation * Point defects * Persistent slip band * Intrusion * Extrusion Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 2.275, year: 2014

  13. Improvement of defect characterization in ultrasonic testing by adaptative learning network

    International Nuclear Information System (INIS)

    Bieth, M.; Adamonis, D.C.; Jusino, A.

    1982-01-01

    Numerous methods exist now for signal analysis in ultrasonic testing. These methods give more or less accurate information for defects characterization. In this paper is presented the development of a particular system based on a computer Signal processing: the Adaptative Learning Network (ALN) allowing the discrimination of defects in function of their nature. The ultrasonic signal is sampled and characterized by parameters amplitude-time and amplitude-frequency. The method was tested on stainless steel tubes welds showing fatigue cracks. The ALN model developed allows, under certain conditions, the discrimination of cracks from other defects [fr

  14. Utilizing Peer Mentor Roles in Learning Communities

    Science.gov (United States)

    Rieske, Laura Jo; Benjamin, Mimi

    2015-01-01

    For a number of learning community programs, peer mentors provide an additional layer of staffing support. This chapter highlights peer mentor roles from a sample of programs and suggests important components for the construction of these roles.

  15. Forensic Learning Disability Nursing Role Analysis

    Science.gov (United States)

    Mason, Tom; Phipps, Dianne; Melling, Kat

    2011-01-01

    This article reports on a study carried out on the role constructs of forensic and nonforensic Learning Disability Nursing in relation to six binary themes. The aims were to identify if there were differences in perceptions of forensic learning disability nurses and nonforensic learning disability nurses in relation to the six binary themes of the…

  16. Biological Background of Kh.DIC Mice and Their Learning and Memory Defects

    Institute of Scientific and Technical Information of China (English)

    潘卫松; 邢东明; 秦川; 孙虹; 高虹; 金文; 杜力军

    2003-01-01

    The learning ability of the Kh.DIC mice, a mutant of the Kunming mice, was studied to analyze its memory development.The mice's brain function was evaluated using a water maze with the amount of monoamines measured by fluorospectrophotometry and enzyme activities detected by ultraviolet spectrophotometry.The mice were found to have spacial learning and memory defects at the age of 1 month in both ordinary animals and in special pathogen free (SPF) animals.At the same time, the amount of monoamines and the activities of monoamine oxidase-B and dopamine-β-hydroxylase differed from those of the Kunming mice.The defects might be related to the differences in the monoamine neurotransmitter system.The results suggest that the DIC mice may be useful economic animal models for the study of brain defects.

  17. Rendering photoreactivity to ceria. The role of defects

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chengwu; Yu, Xiaojuan; Heissler, Stefan; Weidler, Peter G.; Nefedov, Alexei; Wang, Yuemin; Woell, Christof [Institute of Functional Interfaces, IFG, Karlsruhe Institute of Technology - KIT, Eggenstein-Leopoldshafen (Germany); Plessow, Philipp N.; Studt, Felix [Institute of Catalysis Research and Technology, IKFT, Karlsruhe Institute of Technology - KIT, Eggenstein-Leopoldshafen (Germany)

    2017-11-06

    The photoreactivity of ceria, a photochemically inert oxide with a large band gap, can be increased to competitive values by introducing defects. This previously unexplained phenomenon has been investigated by monitoring the UV-induced decomposition of N{sub 2}O on well-defined single crystals of ceria by using infrared reflection-absorption spectroscopy (IRRAS). The IRRAS data, in conjunction with theory, provide direct evidence that reducing the ceria(110) surface yields high photoreactivity. No such effects are seen on the (111) surface. The low-temperature photodecomposition of N{sub 2}O occurs at surface O vacancies on the (110) surface, where the electron-rich cerium cations with a significantly lowered coordination number cause a local lowering of the huge band gap (ca. 6 eV). The quantum efficiency of strongly reduced ceria(110) surfaces in the photodecomposition of N{sub 2}O amounts to 0.03 %, and is thus comparable to that reported for the photooxidation of CO on rutile TiO{sub 2}(110). (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Teacher roles in Learning Games

    DEFF Research Database (Denmark)

    Magnussen, Rikke

    2007-01-01

    the roles as forensic experts who solve a series of murder cases. When teachers use this type of games, they have to adapt to new teaching situations and roles. This includes the fictional role in a game, but also the role as a supervisor for a group of students that play the role as professional experts. I...

  19. FIBER OPTICS: Role of point defects in the photosensitivity of hydrogen-loaded phosphosilicate glass

    Science.gov (United States)

    Larionov, Yu V.

    2010-08-01

    It is shown that point defect modifications in hydrogen-loaded phosphosilicate glass (PSG) do not play a central role in determining its photosensitivity. Photochemical reactions that involve a two-step point defect modification and pre-exposure effect are incapable of accounting for photoinduced refractive index changes. It seems likely that a key role in UV-induced refractive index modifications is played by structural changes in the PSG network. Experimental data are presented that demonstrate intricate network rearrangement dynamics during UV exposure of PSG.

  20. The Role of Motivation in Language Learning

    OpenAIRE

    Rahman, Anwar

    2011-01-01

    The mastery of English learning is influenced by some variables, one of them is motivation. Motivation in learning second language is classified as integrative motivation and instrumental motivation. Some experts of language teaching also categorized motivation into two types namely intrinsic motivation and extrinsic motivation. This paper discusses about kinds of motivation and how it takes a role in influencing students mastery in learning language. It was literature study that focused to f...

  1. The Role of Emotion in Word Learning

    Science.gov (United States)

    Doan, S. N.

    2010-01-01

    The way in which emotion interacts with cognition has been of great interest to researchers for hundreds of years. Emotion has been shown to play an important role in attention, learning and memory. However, the way in which emotion influences the basic process of word learning in infancy has largely been ignored. In the current paper, the…

  2. Research on cross - Project software defect prediction based on transfer learning

    Science.gov (United States)

    Chen, Ya; Ding, Xiaoming

    2018-04-01

    According to the two challenges in the prediction of cross-project software defects, the distribution differences between the source project and the target project dataset and the class imbalance in the dataset, proposing a cross-project software defect prediction method based on transfer learning, named NTrA. Firstly, solving the source project data's class imbalance based on the Augmented Neighborhood Cleaning Algorithm. Secondly, the data gravity method is used to give different weights on the basis of the attribute similarity of source project and target project data. Finally, a defect prediction model is constructed by using Trad boost algorithm. Experiments were conducted using data, come from NASA and SOFTLAB respectively, from a published PROMISE dataset. The results show that the method has achieved good values of recall and F-measure, and achieved good prediction results.

  3. Role of the bond defect for structural transformations between crystalline and amorphous silicon: A molecular-dynamics study

    International Nuclear Information System (INIS)

    Stock, D. M.; Weber, B.; Gaertner, K.

    2000-01-01

    The relation between the bond defect, which is a topological defect, and structural transformations between crystalline and amorphous silicon, is studied by molecular-dynamics simulations. The investigation of 1-keV boron implantation into crystalline silicon proves that the bond defect can also be generated directly by collisional-induced bond switching in addition to its formation by incomplete recombination of primary defects. This supports the assumption that the bond defect may play an important role in the amorphization process of silicon by light ions. The analysis of the interface between (001) silicon and amorphous silicon shows that there are two typical defect configurations at the interface which result from two different orientations of the bond defect with respect to the interface. Thus the bond defect appears to be a characteristic structural feature of the interface. Moreover, annealing results indicate that the bond defect acts as a growth site for interface-mediated crystallization

  4. The Role of Motivation in Language Learning

    Institute of Scientific and Technical Information of China (English)

    李玉红

    2004-01-01

    The role of motivation in language learning has been studied since the 1960s. It is indeed one of the most important areas of linguistics. This paper suggests strategies of motivating language learners and focuses on the role which motivation can play in language learning. The concept of motivation from different points of view is defined, a number of suggestions on how to motivate language learners are presented and the role of motivation based on various motivational theories are highlighted. With regard to the role of motivation in language learning, it is concluded that motivation plays an increasingly important role in many aspects, such as identifying with the target language society, achieving long-term and short-term goals, improving language learners' internal and external powers and exerting a group force. It also indicates that there should be more research areas to be examined and a long way is probably requlred to go in future theoretical and practical study.

  5. The role of defects in fluorescent silicon carbide layers grown by sublimation epitaxy

    DEFF Research Database (Denmark)

    Schimmel, Saskia; Kaiser, Michl; Jokubavicius, Valdas

    Donor-acceptor co-doped silicon carbide layers are promising light converters for novel monolithic all-semiconductor LEDs due to their broad-band donor-acceptor pair luminescence and potentially high internal quantum efficiency. Besides appropriate doping concentrations yielding low radiative...... lifetimes, high nonradiative lifetimes are crucial for efficient light conversion. Despite the excellent crystalline quality that can generally be obtained by sublimation epitaxy according to XRD measurements, the role of defects in f-SiC is not yet well understood. Recent results from room temperature...... photoluminescence, charge carrier lifetime measurements by microwave detected photoconductivity and internal quantum efficiency measurements suggest that the internal quantum efficiency of f-SiC layers is significantly affected by the incorporation of defects during epitaxy. Defect formation seems to be related...

  6. The role of Frenkel defect diffusion in dynamic annealing in ion-irradiated Si

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, J. B.; Aji, L. B. Bayu; Martin, A. A.; Shin, S. J.; Shao, L.; Kucheyev, S. O.

    2017-01-06

    The formation of stable radiation damage in crystalline solids often proceeds via complex dynamic annealing processes, involving migration and interaction of ballistically-generated point defects. The dominant dynamic annealing processes, however, remain unknown even for crystalline Si. Here, we use a pulsed ion beam method to study defect dynamics in Si bombarded in the temperature range from -20 to 140 °C with 500 keV Ar ions. Results reveal a defect relaxation time constant of ~10–0.2 ms, which decreases monotonically with increasing temperature. The dynamic annealing rate shows an Arrhenius dependence with two well-defined activation energies of 73 ± 5 meV and 420 ± 10 meV, below and above 60 °C, respectively. Rate theory modeling, bench-marked against this data, suggests a crucial role of both vacancy and interstitial diffusion, with the dynamic annealing rate limited by the migration and interaction of vacancies.

  7. Principals' Collaborative Roles as Leaders for Learning

    Science.gov (United States)

    Kitchen, Margaret; Gray, Susan; Jeurissen, Maree

    2016-01-01

    This article draws on data from three multicultural New Zealand primary schools to reconceptualize principals' roles as leaders for learning. In doing so, the writers build on Sinnema and Robinson's (2012) article on goal setting in principal evaluation. Sinnema and Robinson found that even principals hand-picked for their experience fell short on…

  8. Defect characterization by an adaptive learning classifier in ultrasonic inspection of ferritic materials

    International Nuclear Information System (INIS)

    Grozellier, M.; Bieth, M.; Romy, D.

    1985-01-01

    The purpose of the work presented here is to determine the efficiency and reliability of the discrimination method ''Adapatative Learning Network''. This process is used to identify the nature of defects detected during Ultrasonic Testing (UT), by analysing some of the echo parameters calculated in temporal and frequency domains. The survey which dealt with several hundreds of echoes, revealed that the machined artificial reflectors, well defined geometrically, were identified with a probability exceeding 95 %. The fatigue cracks, producing less characteristic echoes, are identified with a slightly lower probability (90 % - 95 %)

  9. Identifying Structural Flow Defects in Disordered Solids Using Machine-Learning Methods

    Science.gov (United States)

    Cubuk, E. D.; Schoenholz, S. S.; Rieser, J. M.; Malone, B. D.; Rottler, J.; Durian, D. J.; Kaxiras, E.; Liu, A. J.

    2015-03-01

    We use machine-learning methods on local structure to identify flow defects—or particles susceptible to rearrangement—in jammed and glassy systems. We apply this method successfully to two very different systems: a two-dimensional experimental realization of a granular pillar under compression and a Lennard-Jones glass in both two and three dimensions above and below its glass transition temperature. We also identify characteristics of flow defects that differentiate them from the rest of the sample. Our results show it is possible to discern subtle structural features responsible for heterogeneous dynamics observed across a broad range of disordered materials.

  10. Deterministic Role of Collision Cascade Density in Radiation Defect Dynamics in Si

    Science.gov (United States)

    Wallace, J. B.; Aji, L. B. Bayu; Shao, L.; Kucheyev, S. O.

    2018-05-01

    The formation of stable radiation damage in solids often proceeds via complex dynamic annealing (DA) processes, involving point defect migration and interaction. The dependence of DA on irradiation conditions remains poorly understood even for Si. Here, we use a pulsed ion beam method to study defect interaction dynamics in Si bombarded in the temperature range from ˜-30 ° C to 210 °C with ions in a wide range of masses, from Ne to Xe, creating collision cascades with different densities. We demonstrate that the complexity of the influence of irradiation conditions on defect dynamics can be reduced to a deterministic effect of a single parameter, the average cascade density, calculated by taking into account the fractal nature of collision cascades. For each ion species, the DA rate exhibits two well-defined Arrhenius regions where different DA mechanisms dominate. These two regions intersect at a critical temperature, which depends linearly on the cascade density. The low-temperature DA regime is characterized by an activation energy of ˜0.1 eV , independent of the cascade density. The high-temperature regime, however, exhibits a change in the dominant DA process for cascade densities above ˜0.04 at.%, evidenced by an increase in the activation energy. These results clearly demonstrate a crucial role of the collision cascade density and can be used to predict radiation defect dynamics in Si.

  11. Implementation of Chaotic Gaussian Particle Swarm Optimization for Optimize Learning-to-Rank Software Defect Prediction Model Construction

    Science.gov (United States)

    Buchari, M. A.; Mardiyanto, S.; Hendradjaya, B.

    2018-03-01

    Finding the existence of software defect as early as possible is the purpose of research about software defect prediction. Software defect prediction activity is required to not only state the existence of defects, but also to be able to give a list of priorities which modules require a more intensive test. Therefore, the allocation of test resources can be managed efficiently. Learning to rank is one of the approach that can provide defect module ranking data for the purposes of software testing. In this study, we propose a meta-heuristic chaotic Gaussian particle swarm optimization to improve the accuracy of learning to rank software defect prediction approach. We have used 11 public benchmark data sets as experimental data. Our overall results has demonstrated that the prediction models construct using Chaotic Gaussian Particle Swarm Optimization gets better accuracy on 5 data sets, ties in 5 data sets and gets worse in 1 data sets. Thus, we conclude that the application of Chaotic Gaussian Particle Swarm Optimization in Learning-to-Rank approach can improve the accuracy of the defect module ranking in data sets that have high-dimensional features.

  12. The role of surface defects in HOPG on the electrochemical and physical deposition of Ag

    Directory of Open Access Journals (Sweden)

    R. PETROVIC

    1999-08-01

    Full Text Available The role of defects on a substrate surface during the initial stages of nucleation and growth of Ag deposited electrochemically and physically on highly oriented pyrolytic graphite (HOPG has been observed ex situ by scanning tunneling microscopy (STM. The silver was electrodeposited under current controlled electrochemical conditions at 26 µA/cm2, which corresponded to a deposition rate of 0.1 monolayers (ML per second. For comparison, physical deposition of Ag on HOPG was performed by DC Ar+ ion sputtering, at the same deposition rate and for the same deposition times. In both cases, Ag grows in an island growth mode, but the distribution of the islands appears to be quite different. In physical deposition, the Ag islands are almost homogeneously distributed over the substrate surface and a slight accumulation of islands on steps does not contribute significantly to the overall morphology. This indicates the crucial role of point defects on the substrate in the initial stages of nucleation. In electrochemical deposition, more lined defects are observed after a flow of current, and their role in the beginning of the nucleation is more pronounced. Lined defects are responsible for the string-like shaped domains of deposited atoms. Also, the existence of string-like shaped nucleation exclusion zones is indicated. The problem of the formation of nucleation exclusion zones, which appear only in electrochemical deposition, has been reconsidered and a new explanaton of their formation is given. A mathematical model for the calculation of the radius of the nucleation exclusion zone has been developed.

  13. Application of Learning Methods to Local Electric Field Distributions in Defected Dielectric Materials

    Science.gov (United States)

    Ferris, Kim; Jones, Dumont

    2014-03-01

    Local electric fields reflect the structural and dielectric fluctuations in a semiconductor, and affect the material performance both for electron transport and carrier lifetime properties. In this paper, we use the LOCALF methodology with periodic boundary conditions to examine the local electric field distributions and its perturbations for II-VI (CdTe, Cd(1-x)Zn(x)Te) semiconductors, containing Te inclusions and small fluctuations in the local dielectric susceptibility. With inclusion of the induced-field term, the electric field distribution shows enhancements and diminishments compared to the macroscopic applied field, reflecting the microstructure characteristics of the dielectric. Learning methods are applied to these distributions to assess the spatial extent of the perturbation, and determine an electric field defined defect size as compared to its physical dimension. Critical concentrations of defects are assessed in terms of defect formation energies. This work was supported by the US Department of Homeland Security, Domestic Nuclear Detection Office, under competitively awarded contract/IAA HSHQDC-08-X-00872-e. This support does not constitute an express or implied endorsement on the part of the Gov't.

  14. Role of point defects and additives in kinetics of hydrogen storage materials

    Science.gov (United States)

    van de Walle, Chris

    2010-03-01

    First-principles computational studies of hydrogen interactions with storage materials can provide direct insight into the processes of H uptake and release, and may help in developing guidelines for designing storage media with improved storage capacity and kinetics. One important conclusion is that the defects involved in kinetics of semiconducting or insulating H-storage materials are charged, and hence their formation energy is Fermi-level dependent and can be affected by the presence of impurities that change the Fermi level [1,2]. This provides an explanation for the role played by transition-metal impurities in the kinetics of NaAlH4 and related materials. Desorption of H and decomposition of NaAlH4 requires not only mass transport of H but also of Al and/or Na. This process is mediated by native defects. We have investigated the structure, stability, and migration enthalpy of native defects based on density functional theory. The results allow us to estimate diffusion activation energies for the defects that may be involved in mass transport. Most of the relevant defects exist in charge states other than neutral, and consideration of these charge states is essential for a proper description of kinetics. We propose specific new mechanisms to explain the observed activation energies and their dependence on the presence of impurities. We have also expanded our studies to materials other than NaAlH4. In the case of LiBH4 and Li4BN3H10 we have found that the calculations have predictive power in terms of identifying which impurities will actually enhance kinetics. Other complex hydrides that we are currently investigating include Li2NH and LiNH2. [4pt] [1] A. Peles and C. G. Van de Walle, Phys. Rev. B 76, 214101 (2007). [0pt] [2] C. G. Van de Walle, A. Peles, A. Janotti, and G. B. Wilson-Short, Physica B 404, 793 (2009).

  15. Customer's potential value: The role of learning

    OpenAIRE

    Komulainen, Hanna; Mainela, Tuija; Tähtinen, Jaana

    2013-01-01

    Current views on value creation emphasize the role of the customer, mutual investments, and value co-creation. Nevertheless, at present the customer-focused research concentrates on value expectations and value experiences as outcomes but disregards the analysis of potential value that is dependent on the customer's activity and learning in the process. The present study explores customer perceived value as a multidimensional phenomenon incorporating expected, realized, and potential dimensio...

  16. Role of masking oxide on silicon in processes of defect generation at formation of SIMOX structures

    CERN Document Server

    Askinazi, A Y; Miloglyadova, L V

    2002-01-01

    One investigated into Si-SiO sub 2 structures formed by implantation of oxygen ions into silicon (SIMOX-technology) by means of techniques based on measuring of high-frequency volt-farad characteristics and by means of electroluminescence. One determined existence of electrically active centres and of luminescence centres in the formed oxide layer near boundary with silicon. One clarified the role SiO sub 2 masking layer in silicon in defect generation under formation of the masked oxide layer. One established dependence of concentration of electrically active and luminescence centres on thickness of masking layer

  17. Investigation of intrinsic and extrinsic defects effective role on producing intense red emission in ZnO:Eu nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, Mehrdad, E-mail: najafi@shahroodut.ac.ir; Haratizadeh, Hamid

    2015-05-15

    Highlights: • Effective role of defects on producing red emission at indirect excitation. • V{sub Zn} and V{sub O} defects have important role on energy transfer. • Mg related defects and Zn{sub i} defects were responsible for blue emission. • Extrinsic and intrinsic defects mediated energy transfer to sensitize Eu{sup 3+} ions. • Decrease of red emission because of diminishing in oxygen vacancy. - Abstract: Europium doped ZnO nanorads and nanosheets were synthesized by hydrothermal method. Effects of Mg doping, morphology and annealing in oxygen ambient on structural and optical properties of ZnO nanostructures were investigated using X-ray diffraction (XRD), particle size analysis (PSA), thermo gravimetric analysis (TGA), differential thermal analysis (DTA), differential thermo gravimetry (DTG), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). This study recommends that both of intrinsic and extrinsic defects facilitate energy transfer (ET) from the ZnO host to Eu{sup 3+} ions and consequently have efficient role on producing intense red emission at indirect excitation. The results also showed that annealing process improved the crystal structure of ZnO nanosheets due to decrease of surface defects; however decreased ET and red emission because of diminishing in oxygen vacancy. In addition in ZnO nanorods sample with more surface area in comparison with ZnO nanosheets sample deep level emissions are enhanced.

  18. DEEP LEARNING AND IMAGE PROCESSING FOR AUTOMATED CRACK DETECTION AND DEFECT MEASUREMENT IN UNDERGROUND STRUCTURES

    Directory of Open Access Journals (Sweden)

    F. Panella

    2018-05-01

    Full Text Available This work presents the combination of Deep-Learning (DL and image processing to produce an automated cracks recognition and defect measurement tool for civil structures. The authors focus on tunnel civil structures and survey and have developed an end to end tool for asset management of underground structures. In order to maintain the serviceability of tunnels, regular inspection is needed to assess their structural status. The traditional method of carrying out the survey is the visual inspection: simple, but slow and relatively expensive and the quality of the output depends on the ability and experience of the engineer as well as on the total workload (stress and tiredness may influence the ability to observe and record information. As a result of these issues, in the last decade there is the desire to automate the monitoring using new methods of inspection. The present paper has the goal of combining DL with traditional image processing to create a tool able to detect, locate and measure the structural defect.

  19. The role of language in learning physics

    Science.gov (United States)

    Brookes, David T.

    Many studies in PER suggest that language poses a serious difficulty for students learning physics. These difficulties are mostly attributed to misunderstanding of specialized terminology. This terminology often assigns new meanings to everyday terms used to describe physical models and phenomena. In this dissertation I present a novel approach to analyzing of the role of language in learning physics. This approach is based on the analysis of the historical development of physics ideas, the language of modern physicists, and students' difficulties in the areas of quantum mechanics, classical mechanics, and thermodynamics. These data are analyzed using linguistic tools borrowed from cognitive linguistics and systemic functional grammar. Specifically, I combine the idea of conceptual metaphor and grammar to build a theoretical framework that accounts for: (1) the role and function that language serves for physicists when they speak and reason about physical ideas and phenomena, (2) specific features of students' reasoning and difficulties that may be related to or derived from language that students read or hear. The theoretical framework is developed using the methodology of a grounded theoretical approach. The theoretical framework allows us to make predictions about the relationship between student discourse and their conceptual and problem solving difficulties. Tests of the theoretical framework are presented in the context of "heat" in thermodynamics and "force" in dynamics. In each case the language that students use to reason about the concepts of "heat" and "force" is analyzed using the theoretical framework. The results of this analysis show that language is very important in students' learning. In particular, students are (1) using features of physicists' conceptual metaphors to reason about physical phenomena, often overextending and misapplying these features, (2) drawing cues from the grammar of physicists' speech and writing to categorize physics

  20. The role of point defect clusters in reactor pressure vessel embrittlement

    International Nuclear Information System (INIS)

    Stoller, R.E.

    1993-01-01

    Radiation-induced point defect clusters (PDC) are a plausible source of matrix hardening in reactor pressure vessel (RPV) steels in addition to copper-rich precipitates. These PDCs can be of either interstitial or vacancy type, and could exist in either 2 or 3-D shapes, e.g. small loops, voids, or stacking fault tetrahedra. Formation and evolution of PDCs are primarily determined by displacement damage rate and irradiation temperature. There is experimental evidence that size distributions of these clusters are also influenced by impurities such as copper. A theoretical model has been developed to investigate potential role of PDCs in RPV embrittlement. The model includes a detailed description of interstitial cluster population; vacancy clusters are treated in a more approximate fashion. The model has been used to examine a broad range of irradiation and material parameters. Results indicate that magnitude of hardening increment due to these clusters can be comparable to that attributed to copper precipitates. Both interstitial and vacancy type defects contribute to this hardening, with their relative importance determined by the specific irradiation conditions

  1. GESTURE'S ROLE IN CREATING AND LEARNING LANGUAGE.

    Science.gov (United States)

    Goldin-Meadow, Susan

    2010-09-22

    Imagine a child who has never seen or heard language. Would such a child be able to invent a language? Despite what one might guess, the answer is "yes". This chapter describes children who are congenitally deaf and cannot learn the spoken language that surrounds them. In addition, the children have not been exposed to sign language, either by their hearing parents or their oral schools. Nevertheless, the children use their hands to communicate--they gesture--and those gestures take on many of the forms and functions of language (Goldin-Meadow 2003a). The properties of language that we find in these gestures are just those properties that do not need to be handed down from generation to generation, but can be reinvented by a child de novo. They are the resilient properties of language, properties that all children, deaf or hearing, come to language-learning ready to develop. In contrast to these deaf children who are inventing language with their hands, hearing children are learning language from a linguistic model. But they too produce gestures, as do all hearing speakers (Feyereisen and de Lannoy 1991; Goldin-Meadow 2003b; Kendon 1980; McNeill 1992). Indeed, young hearing children often use gesture to communicate before they use words. Interestingly, changes in a child's gestures not only predate but also predict changes in the child's early language, suggesting that gesture may be playing a role in the language-learning process. This chapter begins with a description of the gestures the deaf child produces without speech. These gestures assume the full burden of communication and take on a language-like form--they are language. This phenomenon stands in contrast to the gestures hearing speakers produce with speech. These gestures share the burden of communication with speech and do not take on a language-like form--they are part of language.

  2. The role of defects in the design of space elevator cable: From nanotube to megatube

    Energy Technology Data Exchange (ETDEWEB)

    Pugno, Nicola M. [Department of Structural Engineering and Geotechnics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy)], E-mail: nicola.pugno@polito.it

    2007-09-15

    Researchers are claiming that the feasibility of space elevator cable is now realistic, thanks to carbon nanotube technology, proposing its realization within a decade. However, the current view of basing the design of the megacable on the theoretical strength of a single carbon nanotube is naive, as has recently been emphasized. In this paper the role of thermodynamically unavoidable atomistic defects with different size and shape is quantified on brittle fracture, fatigue and elasticity, for nanotubes and nanotube bundles. Nonasymptotic regimes, elastic plasticity, rough cracks, finite domains and size effects are also discussed. The results are compared with atomistic simulations and nanotensile tests of carbon nanotubes. Key simple formulas for the design of a flaw-tolerant space elevator megacable are reported, suggesting that it would need a taper ratio (for uniform stress) of about two orders of magnitude larger than currently proposed.

  3. Online Surface Defect Identification of Cold Rolled Strips Based on Local Binary Pattern and Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2018-03-01

    Full Text Available In the production of cold-rolled strip, the strip surface may suffer from various defects which need to be detected and identified using an online inspection system. The system is equipped with high-speed and high-resolution cameras to acquire images from the moving strip surface. Features are then extracted from the images and are used as inputs of a pre-trained classifier to identify the type of defect. New types of defect often appear in production. At this point the pre-trained classifier needs to be quickly retrained and deployed in seconds to meet the requirement of the online identification of all defects in the environment of a continuous production line. Therefore, the method for extracting the image features and the training for the classification model should be automated and fast enough, normally within seconds. This paper presents our findings in investigating the computational and classification performance of various feature extraction methods and classification models for the strip surface defect identification. The methods include Scale Invariant Feature Transform (SIFT, Speeded Up Robust Features (SURF and Local Binary Patterns (LBP. The classifiers we have assessed include Back Propagation (BP neural network, Support Vector Machine (SVM and Extreme Learning Machine (ELM. By comparing various combinations of different feature extraction and classification methods, our experiments show that the hybrid method of LBP for feature extraction and ELM for defect classification results in less training and identification time with higher classification accuracy, which satisfied online real-time identification.

  4. The role of learning technologists in supporting e-research

    Directory of Open Access Journals (Sweden)

    Susi Peacock

    2009-12-01

    Full Text Available This article explores how the role of learning technologists, a professional group that has emerged during the last 15 to 20 years, may be diversifying to include supporting e-research. It contributes to the current debate about the emerging profession and the roles it should play in contemporary higher education. Previous studies have shown that, typically, the profession's role has focussed almost exclusively on curriculum development; traditionally, learning technologists work with students and tutors to enhance the learning environment with technology. This article presents two case studies of PhD research that used a standard e-learning tool, the virtual learning environment (VLE, to conduct focus groups online. The case studies demonstrate the expert role of the learning technologist in supporting researchers to make informed decisions about whether and how to use e-learning tools to conduct qualitative e-research. The learning technologist advised on the potential advantages and limitations of using the VLE for research and fostered collaborative, working relationships with the researchers, acquiring extensive background knowledge about their projects. This required the learning technologist to draw upon her own experience with research into e-learning and on her professional experience gained from supporting curriculum developments. It is suggested that many learning technologists could extend their roles, transferring their knowledge to include supporting e-research. A more inclusive model of the learning technologist's role in academia could help address the potential polarisation of the profession into researchers and practitioners.

  5. The Role of a Commander in Military Lessons Learned Systems

    Directory of Open Access Journals (Sweden)

    Zenon Waliński

    2015-06-01

    Full Text Available The aim of the paper is to investigate the role of a commander in military Lessons Learned systems. In order to achieve the aim, the paper presents (1 the architecture of the Lessons Learned capabilities in the U.S. Army, NATO and the Polish Armed Forces, (2 the commander’s role in the Lessons Learned process (3 the commander’s role in fostering Lessons Learned organisation culture. The paper is based on multiple case study analysis including Lessons Learned systems in NATO, the U.S. Army and the Polish Armed Forces.

  6. Learning in the workplace: the role of Nurse Managers.

    Science.gov (United States)

    Yen, Margaret; Trede, Franziska; Patterson, Carmel

    2016-06-01

    Objective This research explores Nurse Managers' (NMs') influence on workplace learning. The facilitation of staff learning has implications for the role of NMs, who are responsible for the quality and safety of patient care. However, this aspect of their work is implicit and there is limited research in the area. Methods This paper discusses the findings from one hospital as part of a broader philosophical hermeneutic study conducted in two public hospitals over a 20-month timeframe. NMs participated in interviews, a period of observation, follow-up interviews and a focus group. Transcribed data was thematically analysed. Eraut's 'Two triangle theory of workplace learning' was used to interpret participants' accounts of how they facilitated workplace learning. Findings The analysis found that NMs worked to positively influence staff performance through learning in three domains: orientating new staff, assessing staff performance and managing underperformance. Conclusions This study purports that NMs influence workplace learning in ways that are seldom recognised. A more conscious understanding of the impact of their role can enable NMs to more purposefully influence workplace learning. Such understanding also has implications for the professional preparation of NMs for their role in the context of workplace learning, facilitating learning for change and enabling the advancement of quality and safety in healthcare. What is known about the topic? Studies exploring the influence of Nurse Managers in workplace learning have been limited to their role in the facilitation of formal learning. There is a paucity of research that examines their role in influencing informal learning. What does this paper add? The findings of this study draw on Eraut's 'Two triangle theory of workplace learning' to further define the interdependent relationship between management and educational practices. What are the implications for practitioners? NMs' awareness and deliberate use of

  7. The role of functionally defective rare germline variants of sialic acid acetylesterase in autoimmune Addison's disease

    Science.gov (United States)

    Gan, Earn H; MacArthur, Katie; Mitchell, Anna L; Pearce, Simon H S

    2012-01-01

    Background Autoimmune Addison's disease (AAD) is a rare condition with a complex genetic basis. A panel of rare and functionally defective genetic variants in the sialic acid acetylesterase (SIAE) gene has recently been implicated in several common autoimmune conditions. We performed a case–control study to determine whether these rare variants are associated with a rarer condition, AAD. Method We analysed nine SIAE gene variants (W48X, M89V, C196F, C226G, R230W, T312M, Y349C, F404S and R479C) in a United Kingdom cohort of 378 AAD subjects and 387 healthy controls. All samples were genotyped using Sequenom iPlex chemistry to characterise primer extension products. Results A heterozygous rare allele at codon 312 (312*M) was found in one AAD patient (0.13%) but was not detected in the healthy controls. The commoner, functionally recessive variant at codon 89 (89*V) was found to be homozygous in two AAD patients but was only found in the heterozygous state in controls. Taking into account all nine alleles examined, 4/378 (1.06%) AAD patients and 1/387 (0.25%) healthy controls carried the defective SIAE alleles, with a calculated odds ratio of 4.13 (95% CI 0.44–97.45, two-tailed P value 0.212, NS). Conclusion We demonstrated the presence of 89*V homozygotes and the 312*M rare allele in the AAD cohort, but overall, our analysis does not support a role for rare variants in SIAE in the pathogenesis of AAD. However, the relatively small collection of AAD patients limits the power to exclude a small effect. PMID:23011869

  8. The role of the sonic hedgehog signalling pathway in patients with midline defects and congenital hypopituitarism.

    Science.gov (United States)

    Gregory, L C; Gaston-Massuet, C; Andoniadou, C L; Carreno, G; Webb, E A; Kelberman, D; McCabe, M J; Panagiotakopoulos, L; Saldanha, J W; Spoudeas, H A; Torpiano, J; Rossi, M; Raine, J; Canham, N; Martinez-Barbera, J P; Dattani, M T

    2015-05-01

    The Gli family of zinc finger (GLI) transcription factors mediates the sonic hedgehog signalling pathway (HH) essential for CNS, early pituitary and ventral forebrain development in mice. Human mutations in this pathway have been described in patients with holoprosencephaly (HPE), isolated congenital hypopituitarism (CH) and cranial/midline facial abnormalities. Mutations in Sonic hedgehog (SHH) have been associated with HPE but not CH, despite murine studies indicating involvement in pituitary development. We aimed to establish the role of the HH pathway in the aetiology of hypothalamo-pituitary disorders by screening our cohort of patients with midline defects and/or CH for mutations in SHH, GLI2, Shh brain enhancer 2 (SBE2) and growth-arrest specific 1 (GAS1). Two variants and a deletion of GLI2 were identified in three patients. A novel variant at a highly conserved residue in the zinc finger DNA-binding domain, c.1552G > A [pE518K], was identified in a patient with growth hormone deficiency and low normal free T4. A nonsynonymous variant, c.2159G > A [p.R720H], was identified in a patient with a short neck, cleft palate and hypogonadotrophic hypogonadism. A 26·6 Mb deletion, 2q12·3-q21·3, encompassing GLI2 and 77 other genes, was identified in a patient with short stature and impaired growth. Human embryonic expression studies and molecular characterisation of the GLI2 mutant p.E518K support the potential pathogenicity of GLI2 mutations. No mutations were identified in GAS1 or SBE2. A novel SHH variant, c.1295T>A [p.I432N], was identified in two siblings with variable midline defects but normal pituitary function. Our data suggest that mutations in SHH, GAS1 and SBE2 are not associated with hypopituitarism, although GLI2 is an important candidate for CH. © 2014 John Wiley & Sons Ltd.

  9. The Role of Small Enterprise in School Students' Workplace Learning.

    Science.gov (United States)

    Mulraney, James; Turner, Peter; Wyatt, Frank; Harris, Roger; Gibson, Terri

    The role of small enterprise in Australian school students' workplace learning was examined. First, the literature on structured workplace learning in Australia, Europe, and North America was reviewed. Next, four structured learning programs in South Australia and four in New South Wales were studied. Interviews were conducted with a total of 41…

  10. The Teacher's Role in Implementing Cooperative Learning in the Classroom.

    NARCIS (Netherlands)

    Gillies, R.; Ashman, A.; Terwel, J.

    2008-01-01

    The teacher’s role in implementing cooperative learning in the classroom provides a comprehensive overview of the theories, research outcomes, challenges and issues in guided cooperative learning. In many chapters there are clear guidelines and discussion about how cooperative learning practices can

  11. The Role of e-Portfolios in Supporting Productive Learning

    Science.gov (United States)

    Yang, Min; Tai, Mui; Lim, Cher Ping

    2016-01-01

    e-Portfolios are a form of authentic assessment with formative functions that include showcasing and sharing learning artifacts, documenting reflective learning processes, connecting learning across various stages and enabling frequent feedback for improvements. This paper examines how e-portfolios take up these formative roles to support…

  12. Eddy Current Signature Classification of Steam Generator Tube Defects Using A Learning Vector Quantization Neural Network

    International Nuclear Information System (INIS)

    Garcia, Gabe V.

    2005-01-01

    A major cause of failure in nuclear steam generators is degradation of their tubes. Although seven primary defect categories exist, one of the principal causes of tube failure is intergranular attack/stress corrosion cracking (IGA/SCC). This type of defect usually begins on the secondary side surface of the tubes and propagates both inwards and laterally. In many cases this defect is found at or near the tube support plates

  13. Absorption and atom mobility in electric field: point defect role in glasses

    International Nuclear Information System (INIS)

    Serruys, Y.; Vigouroux, J.P.

    1986-10-01

    During the surface analysis of dielectric materials, the impinging ionising particles induce point defects localised in the band gap and build an electrical charge. The electric field created by the charged defects modifies the physico-chemical properties of surface and bulk. We show that the fundamental study of defects allows a better understanding of technological phenomena such as dielectric breakdown, fracture and diffusion [fr

  14. Roles of Teachers in Orchestrating Learning in Elementary Science Classrooms

    Science.gov (United States)

    Zhai, Junqing; Tan, Aik-Ling

    2015-01-01

    This study delves into the different roles that elementary science teachers play in the classroom to orchestrate science learning opportunities for students. Examining the classroom practices of three elementary science teachers in Singapore, we found that teachers shuttle between four key roles in enabling student learning in science. Teachers…

  15. Active Learning in Neuroscience: A Manipulative to Simulate Visual Field Defects

    Science.gov (United States)

    Li, Andrew Yue-Lin; Carvalho, Helena

    2016-01-01

    Prevalent in 20-57% of stroke patients, visual field defects have been shown to impact quality of life. Studies have shown increased risk of falling, ambulatory difficulties, impaired reading ability, and feelings of panic in crowded or unfamiliar places in patients with visual field defects. Rehabilitation, independence, and mental health may…

  16. Disturbance of endogenous hydrogen sulfide generation and endoplasmic reticulum stress in hippocampus are involved in homocysteine-induced defect in learning and memory of rats.

    Science.gov (United States)

    Li, Man-Hong; Tang, Ji-Ping; Zhang, Ping; Li, Xiang; Wang, Chun-Yan; Wei, Hai-Jun; Yang, Xue-Feng; Zou, Wei; Tang, Xiao-Qing

    2014-04-01

    Homocysteine (Hcy) is a risk factor for Alzheimer's disease (AD). Hydrogen sulfide (H2S) acts as an endogenous neuromodulator and neuroprotectant. It has been shown that endoplasmic reticulum (ER) stress is involved in the pathological mechanisms of the learning and memory dysfunctions and that H2S exerts its neuroprotective role via suppressing ER stress. In the present work, we explored the effects of intracerebroventricular injection of Hcy on the formation of learning and memory, the generation of endogenous H2S, and the expression of ER stress in the hippocampus of rats. We found that intracerebroventricular injection of Hcy in rats leads to learning and memory dysfunctions in the Morris water maze and novel of object recognition test and decreases in the expression of cystathionine-β-synthase, the major enzyme responsible for endogenous H2S generation, and the generation of endogenous H2S in the hippocampus of rats. We also showed that exposure of Hcy could up-regulate the expressions of glucose-regulated protein 78 (GRP78), CHOP, and cleaved caspase-12, which are the major mark proteins of ER stress, in the hippocampus of rats. Taken together, these results suggest that the disturbance of hippocampal endogenous H2S generation and the increase in ER stress in the hippocampus are related to Hcy-induced defect in learning and memory. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. What can we learn from Raman Spectroscopy on irradiation-induced defects in UO2?

    International Nuclear Information System (INIS)

    Desgranges, L.; Martin, Ph.; Simon, P.; Guimbretiere, G.; Baldinozzi, G.

    2014-01-01

    Recent results on irradiated UO 2 by Raman spectroscopy evidenced Raman lines that are characteristic of irradiation-induced defects. Three main mechanisms are identified to explain their origin: resonant Raman, formation of new molecular entities, or breakdown in symmetry. Arguments are given to consider breakdown in symmetry as the predominant mechanism. A tentative description of the defects at the origin of this symmetry breakdown is proposed in terms of coordination polyhedrons of uranium. This discussion led us to consider that the Raman defect modes could be related to area with different stoichiometry. (authors)

  18. Observation of zone folding induced acoustic topological insulators and the role of spin-mixing defects

    Science.gov (United States)

    Deng, Yuanchen; Ge, Hao; Tian, Yuan; Lu, Minghui; Jing, Yun

    2017-11-01

    This article reports on the experimental realization of a flow-free, pseudospin-based acoustic topological insulator designed using the strategy of zone folding. Robust sound one-way propagation is demonstrated with the presence of non-spin-mixing defects. On the other hand, it is shown that spin-mixing defects, which break the geometric symmetry and therefore the pseudo-time-reversal symmetry, can open up nontrivial band gaps within the edge state frequency band, and their width can be tailored by the extent of the defect. This provides a possible route for realizing tunable acoustic topological insulators.

  19. Role of Defects and Adsorbed Water Film in Influencing the Electrical, Optical and Catalytic Properties of Transition Metal Oxides

    Science.gov (United States)

    Wang, Qi

    Transition metal oxides (TMOs) constitute a large group of materials that exhibit a wide range of optical, electrical, electrochemical, dielectric and catalytic properties, and thus making them highly regarded as promising materials for a variety of applications in next generation electronic, optoelectronic, catalytic, photonic, energy storage and energy conversion devices. Some of the unique properties of TMOs are their strong electron-electron correlations that exists between the valence electrons of narrow d- or f-shells and their ability to exist in variety of oxidation states. This gives TMOs an enormous range of fascinating electronic and other physical properties. Many of these remarkable properties of TMOs arises from the complex surface charge transfer processes at the oxide surface/electrochemical redox species interface and non-stoichiometry due to the presence of lattice vacancies that may cause significant perturbation to the electronic structure of the material. Stoichiometry, oxidation state of the metal center and lattice vacancy defects all play important roles in affecting the physical properties, electronic structures, device behavior and other functional properties of TMOs. However, the underlying relationships between them is not clearly known. For instance, the exchange of electrons between adsorbates and defects can lead to the passivation of existing defect states or formation of new defects, both of which affect defect equilibria, and consequently, functional properties. In depth understanding of the role of lattice defects on the electrical, catalytic and optical properties of TMOs is central to further expansion of the technological applications of TMO based devices. The focus of this work is to elucidate the interactions of vacancy defects with various electrochemical adsorbates in TMOs. The ability to directly probe the interactions of vacancy defects with gas and liquid phase species under in-operando conditions is highly desirable to

  20. Role-playing in the problem-based learning class.

    Science.gov (United States)

    Chan, Zenobia C Y

    2012-01-01

    Learning and teaching have been conceptualized and executed in many styles, such as self-learning, peer learning, and interaction between the learner and mentor. Today, openness to alternative ideas and embracing innovative approaches in nursing education are encouraged in order to meet students' learning interests and needs, and to address ever-changing healthcare requests. Problem-based learning has been widely adopted in nursing education, with various positive effects on students' learning, such as motivated learning, team work, problem-solving skills and critical thinking. Role-plays have been demonstrated as an effective learning strategy that includes an active and experiential feature that facilitates students' autonomy in their health-related learning. However, there is a lack of discussion of whether and how role-play can be used in problem-based learning (PBL). This paper shows the development of a classroom-based innovation using role-play in the PBL class for higher diploma year-one nurse students (a total of 20 students, five per group). This paper consists of five sections: a) the literature on PBL and nurse education, and role-plays as the innovation; b) the PBL case scenario with the illustration of the two role-play scripts, c) student evaluation on role-play in the PBL class; d) discussions on both achievements and limitations of this innovation, and e) the conclusion. It is hoped that this paper will be an example to other nurse educators who are keen on exploring interactive and student-driven learning and teaching strategies in the PBL class. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. The central role of learning in videogaming

    OpenAIRE

    Fabricatore, Carlo; López, Ximena; Dill, Karen E.

    2009-01-01

    In the 21st century, being a parent means having to deal with buying, monitoring, and negotiating about video games. A common question parents have is whether children can learn anything positive or of educational value by playing video games? The answer is “Yes!” Children can learn valuable skills by playing video games.

  2. Smart Training, Smart Learning: The Role of Cooperative Learning in Training for Youth Services.

    Science.gov (United States)

    Doll, Carol A.

    1997-01-01

    Examines cooperative learning in youth services and adult education. Discusses characteristics of cooperative learning techniques; specific cooperative learning techniques (brainstorming, mini-lecture, roundtable technique, send-a-problem problem solving, talking chips technique, and three-step interview); and the role of the trainer. (AEF)

  3. The Role of Audiovisual Mass Media News in Language Learning

    Science.gov (United States)

    Bahrani, Taher; Sim, Tam Shu

    2011-01-01

    The present paper focuses on the role of audio/visual mass media news in language learning. In this regard, the two important issues regarding the selection and preparation of TV news for language learning are the content of the news and the linguistic difficulty. Content is described as whether the news is specialized or universal. Universal…

  4. The Role of Research on Science Teaching and Learning

    Science.gov (United States)

    National Science Teachers Association (NJ1), 2010

    2010-01-01

    Research on science teaching and learning plays an important role in improving science literacy, a goal called for in the National Science Education Standards (NRC 1996) and supported by the National Science Teachers Association (NSTA 2003). NSTA promotes a research agenda that is focused on the goal of enhancing student learning through effective…

  5. Roles of Knowledge in Motor Learning.

    Science.gov (United States)

    1987-02-02

    arm dynamics, previous single trajectory learning algorithms, and much of traditional adaptive control. Thesis Supervisor: Dr. Emilio Bizzi Eugene...and Lim, S.K., 1984, *Joint torque measurement of a direct-drive arm,’ Proc. 23rd Con!. Decision ad Control, Las Vegas , Dec. 12-14, pp. 1332-1337...Dynamic Systems By Learning: A New Control Theory For Servomechanisms of Mechatronics Systems." Proc. 23rd IEEE CDC, Las Vegas , Nevada Arimoto, S., S

  6. Monte Carlo simulations of core/shell nanoparticles containing interfacial defects: Role of disordered ferromagnetic spins

    International Nuclear Information System (INIS)

    Ho, Le Bin; Lan, Tran Nguyen; Hai, Tran Hoang

    2013-01-01

    In this work, we have used the Monte Carlo simulation to investigate the magnetic properties of an isolated composite magnetic nanoparticle with ferromagnetic (FM) core and antiferromagnetic (AFM) shell morphology. The defects were assumed to be randomly located at the AFM interface. The Néel anisotropy was used for the FM interface spins at where there are the lacks of crystal symmetry due to the vacancies at AFM interface. With a moderate defect concentration, the coercive field non-monotonously depends on the Néel anisotropy. We have examined the dependence of coercivity, exchange bias field, and vertical shift on defect concentration. We found that in addition to AFM shell, the disordered FM interface is another pining-source for exchange bias phenomenon. We discuss our simulated results in the relation to recent experimental findings

  7. Light-emitting diode assessment of dentinal defects: the role of presumed extraction forces

    Directory of Open Access Journals (Sweden)

    Marcelo Santos Coelho

    2017-07-01

    Full Text Available Objectives The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time. Materials and Methods The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The × 12.8 magnification was used for the 9 mm slices and × 19.2 magnification for the 3 mm and 6 mm slices under light-emitting diode (LED transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis. Results Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth (p = 0.015. Conclusions LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.

  8. Role of Defects in Swelling and Creep of Irradiated SiC

    Energy Technology Data Exchange (ETDEWEB)

    Szlufarska, Izabela [Univ. of Wisconsin, Madison, WI (United States); Voyles, Paul [Univ. of Wisconsin, Madison, WI (United States); Sridharan, Kumar [Univ. of Wisconsin, Madison, WI (United States); Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-01-16

    Silicon carbide is a promising cladding material because of its high strength and relatively good corrosion resistance. However, SiC is brittle and therefore SiC-based components need to be carefully designed to avoid cracking and failure by fracture. In design of SiC-based composites for nuclear reactor applications it is essential to take into account how mechanical properties are affected by radiation and temperature, or in other words, what strains and stresses develop in this material due to environmental conditions. While thermal strains in SiC can be predicted using classical theories, radiation-induced strains are much less understood. In particular, it is critical to correctly account for radiation swelling and radiation creep, which contribute significantly to dimensional instability of SiC under radiation. Swelling typically increases logarithmically with radiation dose and saturates at relatively low doses (damage levels of a few dpa). Consequently, swelling-induced stresses are likely to develop within a few months of operation of a reactor. Radiation-induced volume swelling in SiC can be as high as 2%, which is significantly higher than the cracking strain of 0.1% in SiC. Swelling-induced strains will lead to enormous stresses and fracture, unless these stresses can be relaxed via some other mechanism. An effective way to achieve stress relaxation is via radiation creep. Although it has been hypothesized that both radiation swelling and radiation creep are driven by formation of defect clusters, existing models for swelling and creep in SiC are limited by the lack of understanding of specific defects that form due to radiation in the range of temperatures relevant to fuel cladding in light water reactors (LWRs) (<1000°C). For example, defects that can be detected with traditional transmission electron microscopy (TEM) techniques account only for 10-45% of the swelling measured in irradiated SiC. Here, we have undertaken an integrated experimental and

  9. Role of Defects in Swelling and Creep of Irradiated SiC

    International Nuclear Information System (INIS)

    Szlufarska, Izabela; Voyles, Paul; Sridharan, Kumar; Katoh, Yutai

    2016-01-01

    Silicon carbide is a promising cladding material because of its high strength and relatively good corrosion resistance. However, SiC is brittle and therefore SiC-based components need to be carefully designed to avoid cracking and failure by fracture. In design of SiC-based composites for nuclear reactor applications it is essential to take into account how mechanical properties are affected by radiation and temperature, or in other words, what strains and stresses develop in this material due to environmental conditions. While thermal strains in SiC can be predicted using classical theories, radiation-induced strains are much less understood. In particular, it is critical to correctly account for radiation swelling and radiation creep, which contribute significantly to dimensional instability of SiC under radiation. Swelling typically increases logarithmically with radiation dose and saturates at relatively low doses (damage levels of a few dpa). Consequently, swelling-induced stresses are likely to develop within a few months of operation of a reactor. Radiation-induced volume swelling in SiC can be as high as 2%, which is significantly higher than the cracking strain of 0.1% in SiC. Swelling-induced strains will lead to enormous stresses and fracture, unless these stresses can be relaxed via some other mechanism. An effective way to achieve stress relaxation is via radiation creep. Although it has been hypothesized that both radiation swelling and radiation creep are driven by formation of defect clusters, existing models for swelling and creep in SiC are limited by the lack of understanding of specific defects that form due to radiation in the range of temperatures relevant to fuel cladding in light water reactors (LWRs) (<1000°C). For example, defects that can be detected with traditional transmission electron microscopy (TEM) techniques account only for 10-45% of the swelling measured in irradiated SiC. Here, we have undertaken an integrated experimental and

  10. The role of learning design and learning analytics in MOOCs

    NARCIS (Netherlands)

    Brouns, Francis; Firssova, Olga

    2016-01-01

    The last couple of years there has been a lot of attention for MOOCs. More and more universities start offering MOOCs. Although the open dimension of MOOC indicates that it is open in every aspect, in most cases it is a course with a structure and a timeline within which learning activities are

  11. Cooperative learning with role play in Chinese pharmacology education.

    Science.gov (United States)

    Wang, Jun; Hu, Xiamin; Xi, Jinglei

    2012-03-01

    Cooperative learning (CL) and role play are both efficient educational tools for enhancing Chinese student active learning and communication skills. This study was designed to obtain student feedback on the format of CL together with role play in the study of pharmacology in Chinese pharmaceutical undergraduates. CL was used in the self-study of new drugs used clinically but neglected in textbook and class teaching, so that groups of students were assigned to become "specialists" in one area of new drugs. Then, these "specialists" taught their new-found knowledge to other groups in role play approach involving an interaction between the pharmacist and a patient. Student perceptions of CL together with role play were examined using an eight-item survey instrument. Students were satisfied with CL together with role play. Majority of the students believed this teaching method enhanced their learning experience, made them gain more pharmacological expertise, increased the awareness of their career in future and self-educational abilities, and fostered their cooperation spirit and confidence. The materials on CL and role play were also believed pertinent. Only 63.4-76.5% and 63.1-37.3% of the students thought "CL and role-play were very funny" and "I felt very relaxed during CL together with role-play", respectively. CL together with role play is an efficient educational tool for enhancing student active-learning and communication skills. But Chinese students will take some time to adapt to this new teaching method.

  12. Role of organizational learning and knowledge management

    Directory of Open Access Journals (Sweden)

    Haleem Fazal

    2017-12-01

    Full Text Available This research is based on Electrocell, a US battery manufacturing company, which was facing problems in its marketing and sales departments as evidenced by its low performance. Following a short introduction to the firm, literature reviews the two recently emerged and widely debated topics, that is, organizational learning and knowledge management. It is followed by the reasons for Electrocell’s declination and revival before and after acquisition by Restart, a US cosmetic manufacturing company. Then, Knowledge Sharing Model, General Hierarchical Model of Organizational Commitment, Knowledge Management, and Learning Organization Capacity, and Three Dimensional Model are described and critically analyzed. At the end, Knowledge Management System Conceptual Model is applied on the case study thoroughly and critically analyzed followed by summary. The research contributes to the literature and offers important implications for academics, managers and strategists that why learning is important and how does it matter to an organization.

  13. The Role of Resorbable Plate and Artificial Bone Substitute in Reconstruction of Large Orbital Floor Defect

    Directory of Open Access Journals (Sweden)

    Ho Kwon

    2016-01-01

    Full Text Available It is essential to reduce and reconstruct bony defects adequately in large orbital floor fracture and defect. Among many reconstructive methods, alloplastic materials have attracted attention because of their safety and ease of use. We have used resorbable plates combined with artificial bone substitutes in large orbital floor defect reconstructions and have evaluated their long-term reliability compared with porous polyethylene plate. A total of 147 patients with traumatic orbital floor fracture were included in the study. Surgical results were evaluated by clinical evaluations, exophthalmometry, and computed tomography at least 12 months postoperatively. Both orbital floor height discrepancy and orbital volume change were calculated and compared with preoperative CT findings. The average volume discrepancy and vertical height discrepancies were not different between two groups. Also, exophthalmometric measurements were not significantly different between the two groups. No significant postoperative complication including permanent diplopia, proptosis, and enophthalmos was noted. Use of a resorbable plate with an artificial bone substitute to repair orbital floor defects larger than 2.5 cm2 in size yielded long-lasting, effective reconstruction without significant complications. We therefore propose our approach as an effective alternative method for large orbital floor reconstructions.

  14. The role of topological spin defects in magnetotransport of CrO2

    International Nuclear Information System (INIS)

    Yanagihara, H; Salamon, M B

    2007-01-01

    We investigated the temperature dependence of the resistivity for a wide temperature range for CrO 2 (100) epitaxial films. The temperature derivative dρ/dT definitely shows the same character as the magnetic heat capacity anomaly in the critical regime even in a finite magnetic field and the critical exponents (α) deduced are consistent with those of 3D Heisenberg ferromagnets. In addition, we found that the spin dependent resistivity over a wide temperature range can be simply proportional to the density of diluted topological spin defects (Skyrmion strings) suggesting that those nontrivial topological defects scatter conduction electrons just like impurities. The excitation energy of such topological defects is quite comparable to that obtained by anomalous Hall effect analysis of the Ye et al model based on the Berry phase. The overall results give a simple picture wherein the density of the topological defects can be a dominant mechanism of resistivity, like the anomalous Hall effect. The results concerning the critical exponent analysis and intuition concerning scattering centres of magnetic disorder suggest a specific picture of the Fisher-Langer model

  15. Relationships Play Primary Role in Boys' Learning

    Science.gov (United States)

    Reichert. Michael; Hawley. Richard

    2013-01-01

    There is a pantheon of literature and popular panic pointing toward the academic ascent of girls and the decline of boys. On the contrary, the reality is different: Boys are learning and succeeding in many places. Two studies find that the places where boys excel have several common characteristics, including teachers who relate to the boys…

  16. Organizational Diagnosis: Its Role in Organizational Learning.

    Science.gov (United States)

    Beer, Michael; Spector, Bert

    1993-01-01

    Sees diagnosis as process that helps organizations enhance their capacity to assess and change dysfunctional aspects of culture and patterns of behavior as basis for developing greater effectiveness and ensuring continuous improvement. Presents framework for understanding "learning diagnosis" in which diagnostic process is part of large-scale…

  17. The Role of Departmental Leadership for Professional Learning Communities

    Science.gov (United States)

    Vanblaere, Bénédicte; Devos, Geert

    2018-01-01

    Purpose: Department heads play a pivotal role in the functioning of departments in secondary schools. However, quantitative research about the role of departmental leadership for the development of professional learning communities (PLCs) in subject departments in secondary schools remains scarce. As PLCs are seen as promising contexts for…

  18. Case studies and role play: learning strategies in nursing.

    Science.gov (United States)

    Cogo, Ana Luísa Petersen; Pai, Daiane Dal; Aliti, Graziella Badin; Hoefel, Heloísa Karnas; Azzolin, Karina de Oliveira; Busin, Lurdes; Unicovsky, Margarita Ana Rubin; Kruse, Maria Henriqueta Luce

    2016-01-01

    to report professors' experience in a public university of Southern region of Brazil using case studies and role play as learning strategies for nursing care of hospitalized adults. learning experience report from the Nursing Care of Adults I class of nursing undergraduate course. the development of case studies and role play considered health care needs from epidemiological profile of chronic noncommunicable diseases morbidity and mortality, nursing as an assisting method, and social aspects of hospitalized individuals. Role play planning was made by creating a stage in laboratory of practices and dialogues comprising students and professors interaction. case studies and role play encouraged students to active search for learning and brought theory closer to real health care situations.

  19. The Role of Corticostriatal Systems in Speech Category Learning.

    Science.gov (United States)

    Yi, Han-Gyol; Maddox, W Todd; Mumford, Jeanette A; Chandrasekaran, Bharath

    2016-04-01

    One of the most difficult category learning problems for humans is learning nonnative speech categories. While feedback-based category training can enhance speech learning, the mechanisms underlying these benefits are unclear. In this functional magnetic resonance imaging study, we investigated neural and computational mechanisms underlying feedback-dependent speech category learning in adults. Positive feedback activated a large corticostriatal network including the dorsolateral prefrontal cortex, inferior parietal lobule, middle temporal gyrus, caudate, putamen, and the ventral striatum. Successful learning was contingent upon the activity of domain-general category learning systems: the fast-learning reflective system, involving the dorsolateral prefrontal cortex that develops and tests explicit rules based on the feedback content, and the slow-learning reflexive system, involving the putamen in which the stimuli are implicitly associated with category responses based on the reward value in feedback. Computational modeling of response strategies revealed significant use of reflective strategies early in training and greater use of reflexive strategies later in training. Reflexive strategy use was associated with increased activation in the putamen. Our results demonstrate a critical role for the reflexive corticostriatal learning system as a function of response strategy and proficiency during speech category learning. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. The learning curve, interobserver, and intraobserver agreement of endoscopic confocal laser endomicroscopy in the assessment of mucosal barrier defects.

    Science.gov (United States)

    Chang, Jeff; Ip, Matthew; Yang, Michael; Wong, Brendon; Power, Theresa; Lin, Lisa; Xuan, Wei; Phan, Tri Giang; Leong, Rupert W

    2016-04-01

    Confocal laser endomicroscopy can dynamically assess intestinal mucosal barrier defects and increased intestinal permeability (IP). These are functional features that do not have corresponding appearance on histopathology. As such, previous pathology training may not be beneficial in learning these dynamic features. This study aims to evaluate the diagnostic accuracy, learning curve, inter- and intraobserver agreement for identifying features of increased IP in experienced and inexperienced analysts and pathologists. A total of 180 endoscopic confocal laser endomicroscopy (Pentax EC-3870FK; Pentax, Tokyo, Japan) images of the terminal ileum, subdivided into 6 sets of 30 were evaluated by 6 experienced analysts, 13 inexperienced analysts, and 2 pathologists, after a 30-minute teaching session. Cell-junction enhancement, fluorescein leak, and cell dropout were used to represent increased IP and were either present or absent in each image. For each image, the diagnostic accuracy, confidence, and quality were assessed. Diagnostic accuracy was significantly higher for experienced analysts compared with inexperienced analysts from the first set (96.7% vs 83.1%, P 0.86 for experienced observers. Features representative of increased IP can be rapidly learned with high inter- and intraobserver agreement. Confidence and image quality were significant predictors of accurate interpretation. Previous pathology training did not have an effect on learning. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  1. [Multi-Target Recognition of Internal and External Defects of Potato by Semi-Transmission Hyperspectral Imaging and Manifold Learning Algorithm].

    Science.gov (United States)

    Huang, Tao; Li, Xiao-yu; Jin, Rui; Ku, Jing; Xu, Sen-miao; Xu, Meng-ling; Wu, Zhen-zhong; Kong, De-guo

    2015-04-01

    The present paper put forward a non-destructive detection method which combines semi-transmission hyperspectral imaging technology with manifold learning dimension reduction algorithm and least squares support vector machine (LSSVM) to recognize internal and external defects in potatoes simultaneously. Three hundred fifteen potatoes were bought in farmers market as research object, and semi-transmission hyperspectral image acquisition system was constructed to acquire the hyperspectral images of normal external defects (bud and green rind) and internal defect (hollow heart) potatoes. In order to conform to the actual production, defect part is randomly put right, side and back to the acquisition probe when the hyperspectral images of external defects potatoes are acquired. The average spectrums (390-1,040 nm) were extracted from the region of interests for spectral preprocessing. Then three kinds of manifold learning algorithm were respectively utilized to reduce the dimension of spectrum data, including supervised locally linear embedding (SLLE), locally linear embedding (LLE) and isometric mapping (ISOMAP), the low-dimensional data gotten by manifold learning algorithms is used as model input, Error Correcting Output Code (ECOC) and LSSVM were combined to develop the multi-target classification model. By comparing and analyzing results of the three models, we concluded that SLLE is the optimal manifold learning dimension reduction algorithm, and the SLLE-LSSVM model is determined to get the best recognition rate for recognizing internal and external defects potatoes. For test set data, the single recognition rate of normal, bud, green rind and hollow heart potato reached 96.83%, 86.96%, 86.96% and 95% respectively, and he hybrid recognition rate was 93.02%. The results indicate that combining the semi-transmission hyperspectral imaging technology with SLLE-LSSVM is a feasible qualitative analytical method which can simultaneously recognize the internal and

  2. Unravelling salutogenic mechanisms in the workplace: the role of learning.

    Science.gov (United States)

    Pijpker, Roald; Vaandrager, Lenneke; Bakker, Evert Jan; Koelen, Maria

    To explore the moderating and mediating role(s) of learning within the relationship between sense of coherence (SOC) and generalized resistance resources. Cross-sectional study (N=481), using a self-administered questionnaire, of employees working in the healthcare sector in the Netherlands in 2017. Four residential healthcare settings and one healthcare-related Facebook group were involved. Multiple linear regression models were used to test for moderating and mediating effects of learning. Social relations, task significance, and job control significantly explained variance in SOC. Conceptual, social, and instrumental learning, combined, moderated the relationship between SOC and task significance. Instrumental learning moderated the relationship between job control and SOC. Social learning also mediated this relationship. Conceptual learning did not show any moderating or mediating effect. The relationship between SOC and the three GRRs seems to be strengthened or explained-to a certain extent-by instrumental and social learning. Healthcare organizations are recommended to promote learning through formal activities as well as through cooperation, feedback, sharing experiences, and job challenges. This requires employee participation and a multilevel interdisciplinary approach. Copyright © 2018 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Role of nitrogen distribution in asymmetric stone-wales defects on electronic transport of graphene nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Hui; Zhao, Jun; Xu, Dahai [College of Physical Science and Technology, Yangtze University, Jingzhou, Hubei 434023 (China); Wei, Jianwei [College of Optoelectronic Information, Chongqing University of Technology, Chongqing 400054 (China)

    2012-01-15

    The authors performed first principles calculation to investigate the influences of nitrogen dopant distribution in the asymmetric Stone-Wales (SW) defect on the electronic transport of zigzag-edged graphene nanoribbon (ZGNR). The stability of doped configurations are evaluated in terms of total energies. It is found that the dopant placed near the edge of the ribbon is the most energetically favorable site. Our results reveal that the doped nanostructures can be substantially modulated as a result of modifications on electronic bands induced by substitutional dopant. Moreover, the individual dopant gives rise to one or two complete electron backscattering centers associated with impurity states in the doped configurations, and the location is determined by the dopant site. Schematics of the atomic structure after asymmetric Stone-Wales defects introduced and different nitrogen substitutional sites. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Electrochemical behavior of thin anodic oxide films on Zircaloy-4: Role of the mobile defects

    International Nuclear Information System (INIS)

    Salot, R.; Lefebvre-Joud, F.; Baroux, B.

    1996-01-01

    The first stages of the electrochemical oxidation of Zircaloy-4 are investigated using simple electrochemical tests and modeling the passive film modifications occurring as a result of contact with the electrolyte. Variations in electrode potential (open-circuit conditions) or current density (potentiodynamic scans) can be simply explained by a high field (F ∼ 10 6 V/cm) assisted passive film growth. Under open-circuit conditions, this field does not vary with exposure time (in the 2 h to 48 h range). The minimum electric field for the onset of high-field behavior is also evaluated and found smaller than the theoretical value which can be explained by a variation in the concentration of mobile defects throughout the film. Measurements of the electrode potential decay after a potentiodynamic scan confirm this model, allowing interpretation of the film modification as a combination of two separate phenomena: film growth under a high electric field and point defect annihilation

  5. Surface magnetization and the role of pattern defects in various types of ripple patterned films

    International Nuclear Information System (INIS)

    Colino, Jose M; Arranz, Miguel A; Barbero, Antonio J; Bollero, A; Camarero, J

    2016-01-01

    We present a detailed study of the magnetic properties of cobalt films with wide-area nanoscale ripple patterns, either on their surface only, or on both the film surface and substrate interface. Angular dependence vectorial-resolved magnetometry measurements and magnetic force microscopy with in situ magnetic field have been used to determine the magnetization reversal processes to correlate them to the different patterned nanostructures. All the samples show well-defined uniaxial magnetic anisotropy with the anisotropy axis lying along the ripple direction. Atomic force microscopy of the different types of pattern reveals various pattern defects: height corrugation and breaks of continuity along the ripple direction, and overlapping ripples and Y-shaped defects (pattern dislocation) across the pattern. In spite of the existence of such customary defects of erosive-regime patterns, the type of low-amplitude, surface-patterned films remarkably behave as a macrospin over almost the whole in-plane angular range (340°), with negligible spread of anisotropy axis or energy. In turn, it is found that high-amplitude surface-patterned films develop an angular distribution of anisotropy axes, probably related to the large distribution of amplitudes in a pattern of short ripples, and a significant distribution of anisotropy fields ΔH k /H k up to 15%. On the other hand, films grow on pre-patterned silicon with a significantly longer mean ripple length, and develop a larger anisotropy energy with H k up to 110 mT, probably because of the double interface effect. The switching fields close to the magnetization easy axis of all types of ripple pattern are not well reproduced by the macrospin approximation, but the observed pattern defects seem to be not responsible for the domain wall pinning that occurs with the field applied along the ripple direction. (paper)

  6. Role of Demyelination Efficiency within Acellular Nerve Scaffolds during Nerve Regeneration across Peripheral Defects

    Directory of Open Access Journals (Sweden)

    Meiqin Cai

    2017-01-01

    Full Text Available Hudson’s optimized chemical processing method is the most commonly used chemical method to prepare acellular nerve scaffolds for the reconstruction of large peripheral nerve defects. However, residual myelin attached to the basal laminar tube has been observed in acellular nerve scaffolds prepared using Hudson’s method. Here, we describe a novel method of producing acellular nerve scaffolds that eliminates residual myelin more effectively than Hudson’s method through the use of various detergent combinations of sulfobetaine-10, sulfobetaine-16, Triton X-200, sodium deoxycholate, and peracetic acid. In addition, the efficacy of this new scaffold in repairing a 1.5 cm defect in the sciatic nerve of rats was examined. The modified method produced a higher degree of demyelination than Hudson’s method, resulting in a minor host immune response in vivo and providing an improved environment for nerve regeneration and, consequently, better functional recovery. A morphological study showed that the number of regenerated axons in the modified group and Hudson group did not differ. However, the autograft and modified groups were more similar in myelin sheath regeneration than the autograft and Hudson groups. These results suggest that the modified method for producing a demyelinated acellular scaffold may aid functional recovery in general after nerve defects.

  7. Role of N defects in paramagnetic CrN at finite temperatures from first principles

    Science.gov (United States)

    Mozafari, E.; Alling, B.; Steneteg, P.; Abrikosov, Igor A.

    2015-03-01

    Simulations of defects in paramagnetic materials at high temperature constitute a formidable challenge to solid-state theory due to the interaction of magnetic disorder, vibrations, and structural relaxations. CrN is a material where these effects are particularly large due to a strong magnetolattice coupling and a tendency for deviations from the nominal 1:1 stoichiometry. In this work, we present a first-principles study of nitrogen vacancies and nitrogen interstitials in CrN at elevated temperature. We report on formation energetics, the geometry of interstitial nitrogen dimers, and the impact on the electronic structure caused by the defects. We find a vacancy formation energy of 2.28 eV with a small effect of temperature, i.e., a formation energy for N interstitial in the form of a -oriented split bond of 3.77 eV with an increase to 3.97 at 1000 K. Vacancies are found to add three electrons, while split-bond interstitial adds one electron to the conduction band. The band gap of defect-free CrN is smeared out due to vibrations, although it is difficult to draw a conclusion about the exact temperature at which the band gap closes from our calculations. However, it is clear that at 900 K there is a nonzero density of electronic states at the Fermi level. At 300 K, our results indicate a border case where the band gap is about to close.

  8. Phononic thermal conductivity in silicene: the role of vacancy defects and boundary scattering

    Science.gov (United States)

    Barati, M.; Vazifehshenas, T.; Salavati-fard, T.; Farmanbar, M.

    2018-04-01

    We calculate the thermal conductivity of free-standing silicene using the phonon Boltzmann transport equation within the relaxation time approximation. In this calculation, we investigate the effects of sample size and different scattering mechanisms such as phonon–phonon, phonon-boundary, phonon-isotope and phonon-vacancy defect. We obtain some similar results to earlier works using a different model and provide a more detailed analysis of the phonon conduction behavior and various mode contributions. We show that the dominant contribution to the thermal conductivity of silicene, which originates from the in-plane acoustic branches, is about 70% at room temperature and this contribution becomes larger by considering vacancy defects. Our results indicate that while the thermal conductivity of silicene is significantly suppressed by the vacancy defects, the effect of isotopes on the phononic transport is small. Our calculations demonstrate that by removing only one of every 400 silicon atoms, a substantial reduction of about 58% in thermal conductivity is achieved. Furthermore, we find that the phonon-boundary scattering is important in defectless and small-size silicene samples, especially at low temperatures.

  9. The critical role of point defects in improving the specific capacitance of δ-MnO2 nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Peng; Metz, Peter; Hey, Trevyn; Gong, Yuxuan; Liu, Dawei; Edwards, Doreen D.; Howe, Jane Y.; Huang, Rong; Misture, Scott T.

    2017-02-23

    3D porous nanostructures built from 2D δ-MnO2 nanosheets are an environmentally friendly and industrially scalable class of supercapacitor electrode material. While both the electrochemistry and defects of this material have been studied, the role of defects in improving the energy storage density of these materials has not been addressed. In this work, δ-MnO2 nanosheet assemblies with 150 m2 g-1 specific surface area are prepared by exfoliation of crystalline KxMnO2 and subsequent reassembly. Equilibration at different pH introduces intentional Mn vacancies into the nanosheets, increasing pseudocapacitance to over 300 F g-1, reducing charge transfer resistance as low as 3 Ω, and providing a 50% improvement in cycling stability. X-ray absorption spectroscopy and high-energy X-ray scattering demonstrate a correlation between the defect content and the improved electrochemical performance. The results show that Mn vacancies provide ion intercalation sites which concurrently improve specific capacitance, charge transfer resistance and cycling stability.

  10. COMPETITIVE INTELLIGENCE: THE ENHANCING ROLE OF ORGANIZATIONAL LEARNING CAPABILITY

    OpenAIRE

    HAMAD, Zaina Mustafa Mahmoud; YOZGAT, Ugur

    2017-01-01

    Performinga strong intelligence grants an organization a guaranteeof long-term success. This paper investigates the enhancing effect of organizational learning capabilities on competitive intelligence atthe commercial banks in Jordan. A sample within top and middle managements was used.Measurement instrument validity and model fit were assessed before testinghypotheses. This study emphasizes the role learning capability plays inenhancing intelligence. Key findings support importance of organi...

  11. The Role of Intelligence in Social Learning.

    Science.gov (United States)

    Vostroknutov, Alexander; Polonio, Luca; Coricelli, Giorgio

    2018-05-02

    Studies in cultural evolution have uncovered many types of social learning strategies that are adaptive in certain environments. The efficiency of these strategies also depends on the individual characteristics of both the observer and the demonstrator. We investigate the relationship between intelligence and the ways social and individual information is utilised to make decisions in an uncertain environment. We measure fluid intelligence and study experimentally how individuals learn from observing the choices of a demonstrator in a 2-armed bandit problem with changing probabilities of a reward. Participants observe a demonstrator with high or low fluid intelligence. In some treatments they are aware of the intelligence score of the demonstrator and in others they are not. Low fluid intelligence individuals imitate the demonstrator more when her fluid intelligence is known than when it is not. Conversely, individuals with high fluid intelligence adjust their use of social information, as the observed behaviour changes, independently of the knowledge of the intelligence of the demonstrator. We provide evidence that intelligence determines how social and individual information is integrated in order to make choices in a changing uncertain environment.

  12. The role of diffusion measurements in the study of crystal lattice defects

    Energy Technology Data Exchange (ETDEWEB)

    Kidson, G V

    1965-07-15

    Measurements of atomic mobility in solids are frequently of direct interest to those concerned with the design, development and utilization of materials in engineering. Increasing attention, however, is currently devoted to an under standing of such properties in terms of the occurrence and nature of point and line defects in the crystals. This paper reviews some recent diffusion studies conducted at C.R,N.L. that provide, in addition to data of interest in nuclear technology, a means of gaining some insight into the more fundamental nature of the lattice defects occurring in the materials. The systems discussed are (i) self diffusion in the high temperature phase of pure zirconium (ii) solute diffusion in lead and (iii) interdiffusion of aluminum and zirconium The unusual and at present incompletely understood results described in (i) are briefly reviewed. Evidence is given to suggest that diffusion occurs either through a dense dislocation network produced as a result of a martensitic phase transformation, or, alternatively, by excess vacancies introduced into the crystal by impurities. In (ii) the extraordinarily rapid diffusion of noble metal solutes in high purity lead single crystals will be discussed n terms of the state of solution of the solute atoms. It will be shown that their diffusion behaviour can be understood by assuming that a fraction f{sub i} of the dissolved solute atoms occupy interstitial sites, The measured diffusion coefficient D{sub m} is related to the interstitial diffusion coefficient by D{sub m} = f{sub i} D{sub i}. In (iii) the formation and rapid growth of single intermetallic compound ZrAl{sub 3} in the diffusion zone formed between pure zirconium and pure aluminum is described and the diffusion mechanism is interpreted in terms of the structure of the compound lattice. The results indicate that ZrAl{sub 3} forms a defect lattice, leading to the relatively rapid migration of aluminum atoms. (author)

  13. Noncrucial role of the defects in the splitting for hydrogen implanted silicon with high boron concentration

    International Nuclear Information System (INIS)

    Popov, V.P.; Stas, V.F.; Antonova, I.V.

    1999-01-01

    The present work deals with the investigation of the electrical and structural properties of heavily boron-doped silicon irradiated by hydrogen. Blistering and splitting processes are enhanced with an increase in boron concentration in the crystal. The measured values of perpendicular strain are over 0.7% which corresponds to a gas overpressure of 0.5 GPa. Processes which lead to blistering and splitting is better described in the frame of a gas pressure model than a model of local stress caused by the defects

  14. Fifth workshop on the role of impurities and defects in silicon device processing. Extended abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Sopori, B.L.; Luque, A.; Sopori, B.; Swanson, D.; Gee, J.; Kalejs, J.; Jastrzebski, L.; Tan, T.

    1995-08-01

    This workshop dealt with engineering aspects and material properties of silicon electronic devices. Crystalline silicon growth, modeling, and properties are discussed in general and as applied to solar cells. Topics considered in discussions of silicon growth include: casting, string ribbons, Al backside contacts, ion implantation, gettering, passivation, and ultrasound treatments. Properties studies include: Electronic properties of defects and impurities, dopant and carrier concentrations, structure and bonding, nitrogen effects, degradation of bulk diffusion length, and recombination parameters. Individual papers from the workshop are indexed separately on the Energy Data Bases.

  15. The role of defects in fluorescent silicon carbide layers grown by sublimation epitaxy

    DEFF Research Database (Denmark)

    Schimmel, Saskia; Kaiser, Michl; Jokubavicius, Valdas

    2014-01-01

    Donor-acceptor co-doped SiC is a promising light converter for novel monolithic all-semiconductor white LEDs due to its broad-band donor-acceptor pair luminescence and potentially high internal quantum efficiency. Besides sufficiently high doping concentrations in an appropriate ratio yielding...... short radiative lifetimes, long nonradiative lifetimes are crucial for efficient light conversion. The impact of different types of defects is studied by characterizing fluorescent silicon carbide layers with regard to photoluminescence intensity, homogeneity and efficiency taking into account...

  16. The roles of the temperature on the structural and electronic properties of deep-level V{sub As}V{sub Ga} defects in gallium arsenide

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Deming, E-mail: xautmdm@163.com; Chen, Xi; Qiao, Hongbo; Shi, Wei; Li, Enling

    2015-07-15

    Highlights: • The energy gap of the Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} is 0.82 eV. • Proves that the Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} belongs to EL2 deep-level defect in GaAs. • Proves that EL2 and EL6 deep-level defects can transform into each other. • Temperature has an important effect on the microstructure of deep-level defects. - Abstract: The roles of temperature on the structural and electronic properties of V{sub As}V{sub Ga} defects in gallium arsenide have been studied by using ab-initio molecular dynamic (MD) simulation. Our calculated results show that the relatively stable quaternary complex defect of Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} can be converted from the V{sub As}V{sub Ga} complex clusters defect between 300 K and 1173 K; however, from 1173 K to 1373 K, the decomposition of the complex defect Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} occurs, turning into a deep-level V{sub As}V{sub Ga} cluster defect and an isolated As{sub Ga} antisite defect, and relevant defect of Ga{sub As} is recovered. The properties of Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} defect has been studied by first-principles calculations based on hybrid density functional theory. Our calculated results show that the Ga{sub As}As{sub Ga}V{sub As}V{sub Ga} belongs to EL2 deep-level defect in GaAs. Thus, we reveal that the temperature has an important effect on the microstructure of deep-level defects and defect energy level in gallium arsenide that EL2 and EL6 deep-level defects have a certain correlation, which means they could transform into each other. Controlling temperature in the growth process of GaAs could change the microstructure of deep-level defects and defect energy levels in gallium arsenide materials, whereby affects the electron transport properties of materials.

  17. Learned Helplessness and Learning Goals: Role played in School Refusal. A Study on Italian Students.

    Directory of Open Access Journals (Sweden)

    Luana Sorrenti

    2016-08-01

    Full Text Available Literature on school refusal has shown a link between school refusal and poor school performance. However, there has been little investigation into the individual underlying factors, and specifically factors directly related to the learning process, such as the learning goals of students and their expectations of success and/or failure. The main purpose of the present study is to investigate the influence of Learned Helplessness (LH and learning goals on school refusal. We hypothesized that LH and learning goals exert a unique role in predicting school refusal above and beyond the roles of academic achievement, age, and gender. The sample consisted of 201 Italian students with an average age of 11.93, with both low (57.2 % of students and high (42.8 % academic achievement. School refusal, LH, and learning goals were measured by means of questionnaires. The results confirm the hypothesis of this study; in fact, we found that learning goals and, above all, LH play a more predictive role of school refusal than academic achievement. These results extend previous studies on school refusal and, for the first time, they provide additional knowledge about this problem, analyzing the relationship between school refusal, learning goals, and LH, still neglected in the literature. Implications on the psychological well-being of students are discussed.

  18. Progressive Structural Defects in Canine Centronuclear Myopathy Indicate a Role for HACD1 in Maintaining Skeletal Muscle Membrane Systems.

    Science.gov (United States)

    Walmsley, Gemma L; Blot, Stéphane; Venner, Kerrie; Sewry, Caroline; Laporte, Jocelyn; Blondelle, Jordan; Barthélémy, Inès; Maurer, Marie; Blanchard-Gutton, Nicolas; Pilot-Storck, Fanny; Tiret, Laurent; Piercy, Richard J

    2017-02-01

    Mutations in HACD1/PTPLA cause recessive congenital myopathies in humans and dogs. Hydroxyacyl-coA dehydratases are required for elongation of very long chain fatty acids, and HACD1 has a role in early myogenesis, but the functions of this striated muscle-specific enzyme in more differentiated skeletal muscle remain unknown. Canine HACD1 deficiency is histopathologically classified as a centronuclear myopathy (CNM). We investigated the hypothesis that muscle from HACD1-deficient dogs has membrane abnormalities in common with CNMs with different genetic causes. We found progressive changes in tubuloreticular and sarcolemmal membranes and mislocalized triads and mitochondria in skeletal muscle from animals deficient in HACD1. Furthermore, comparable membranous abnormalities in cultured HACD1-deficient myotubes provide additional evidence that these defects are a primary consequence of altered HACD1 expression. Our novel findings, including T-tubule dilatation and disorganization, associated with defects in this additional CNM-associated gene provide a definitive pathophysiologic link with these disorders, confirm that dogs deficient in HACD1 are relevant models, and strengthen the evidence for a unifying pathogenesis in CNMs via defective membrane trafficking and excitation-contraction coupling in muscle. These results build on previous work by determining further functional roles of HACD1 in muscle and provide new insight into the pathology and pathogenetic mechanisms of HACD1 CNM. Consequently, alterations in membrane properties associated with HACD1 mutations should be investigated in humans with related phenotypes. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  19. TOOLS FOR COLABORATIVE LEARNING: A ROLE-PLAYING PRACTICE

    Directory of Open Access Journals (Sweden)

    Marta Ortiz-de-Urbina Criado

    2010-11-01

    Full Text Available Role-playing is an active participation tool that facilitates cooperative learning. It has also proved to be more effective in developing competencies than traditional methods. This technique is essential to make theory and practice compatible as is required in order to adapt subjects to the new education system based on the Bolonia’s agreement, especially in Social Sciences disciplines. Consequently, the objective of this paper is to show the effect and use of role-playing applied to management area. Therefore, we analyze and design the role-playing, putting it in practice in the classroom in Human Resource Management subject of different academic degrees. To conclude, this paper has shown the importance of role-playing as a learning tool and development of skills like work cooperation, problem and conflict solving, decision making, and managing complex systems.

  20. Business English: An Individualised Learning Programme -- An Effective but Defective ESP Program

    Science.gov (United States)

    Chi, Gui-min

    2008-01-01

    Business English is the core course for ESP (English for Specific Purposes) programs which empathizes the effectiveness and pragmatism. Feasibility is the crucial element for business English programs especially for in-services business people. Business English-An individualised learning programme is an effective and radical business English…

  1. Role of defects in the process of graphene growth on hexagonal boron nitride from atomic carbon

    Energy Technology Data Exchange (ETDEWEB)

    Dabrowski, J., E-mail: Dabrowski@ihp-microelectronics.com; Lippert, G.; Schroeder, T.; Lupina, G. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany)

    2014-11-10

    Hexagonal boron nitride (h-BN) is an attractive substrate for graphene, as the interaction between these materials is weak enough for high carrier mobility to be retained in graphene but strong enough to allow for some epitaxial relationship. We deposited graphene on exfoliated h-BN by molecular beam epitaxy (MBE), we analyzed the atomistic details of the process by ab initio density functional theory (DFT), and we linked the DFT and MBE results by random walk theory. Graphene appears to nucleate around defects in virgin h-BN. The DFT analysis reveals that sticking of carbon to perfect h-BN is strongly reduced by desorption, so that pre-existing seeds are needed for the nucleation. The dominant nucleation seeds are C{sub N}C{sub B} and O{sub N}C{sub N} pairs and B{sub 2}O{sub 3} inclusions in the virgin substrate.

  2. Role of vacancy defects in Al doped ZnO thin films for optoelectronic devices

    Science.gov (United States)

    Rotella, H.; Mazel, Y.; Brochen, S.; Valla, A.; Pautrat, A.; Licitra, C.; Rochat, N.; Sabbione, C.; Rodriguez, G.; Nolot, E.

    2017-12-01

    We report on the electrical, optical and photoluminescence properties of industry-ready Al doped ZnO thin films grown by physical vapor deposition, and their evolution after annealing under vacuum. Doping ZnO with Al atoms increases the carrier density but also favors the formation of Zn vacancies, thereby inducing a saturation of the conductivity mechanism at high aluminum content. The electrical and optical properties of these thin layered materials are both improved by annealing process which creates oxygen vacancies that releases charge carriers thus improving the conductivity. This study underlines the effect of the formation of extrinsic and intrinsic defects in Al doped ZnO compound during the fabrication process. The quality and the optoelectronic response of the produced films are increased (up to 1.52 mΩ \\cdotcm and 3.73 eV) and consistent with the industrial device requirements.

  3. The Role of Mathematics Learning Centres in Engineering Education.

    Science.gov (United States)

    Fuller, Milton

    2002-01-01

    Points out the diminishing demand for mathematics undergraduate programs and the strong trend in engineering education to make greater use of computer coursework such as Mathcad, Matlab, and other software systems for the mathematical and statistical components of engineering programs. Describes the changing role of mathematics learning centers…

  4. Personal Learning Environments and University Teacher Roles Explored Using Delphi

    Science.gov (United States)

    Shaikh, Zaffar Ahmed; Khoja, Shakeel Ahmed

    2014-01-01

    This paper presents the results of research using an online Delphi method, which aimed to explore university teacher roles and readiness for learner-centred pedagogy, driven by personal learning environments (PLEs). Using a modified Policy Delphi technique, a group of researchers worked with 34 international experts who are university teachers by…

  5. The Role of Elicited Verbal Imitation in Toddlers' Word Learning

    Science.gov (United States)

    Hodges, Rosemary; Munro, Natalie; Baker, Elise; McGregor, Karla; Docking, Kimberley; Arciuli, Joanne

    2016-01-01

    This study is about the role of elicited verbal imitation in toddler word learning. Forty-eight toddlers were taught eight nonwords linked to referents. During training, they were asked to imitate the nonwords. Naming of the referents was tested at three intervals (one minute later [uncued], five minutes, and 1-7 days later [cued]) and recognition…

  6. The Role of Involvement in Learning Management System Success

    Science.gov (United States)

    Klobas, Jane E.; McGill, Tanya J.

    2010-01-01

    Learning management systems (LMS) have been adopted by the majority of higher education institutions and research that explores the factors that influence the success of LMS is needed. This paper investigates the roles of student and instructor involvement in LMS success, using the DeLone and McLean (2003) model of information systems success as a…

  7. An Exploration of Community Learning Disability Nurses' Therapeutic Role

    Science.gov (United States)

    Marsham, Marian

    2012-01-01

    This literature review and primary qualitative research explores therapeutic role from the perspective of Community Learning Disability Nurses. Semi-structured interviews, based on Critical Incident Technique ("Psychol Bull", 51, 1954, 327), and descriptive phenomenological methodology were adopted to elicit data amenable to systematic…

  8. The Role of Structure in Learning Non-Euclidean Geometry

    Science.gov (United States)

    Asmuth, Jennifer A.

    2009-01-01

    How do people learn novel mathematical information that contradicts prior knowledge? The focus of this thesis is the role of structure in the acquisition of knowledge about hyperbolic geometry, a non-Euclidean geometry. In a series of three experiments, I contrast a more holistic structure--training based on closed figures--with a mathematically…

  9. Autophagy failure in Alzheimer's disease and the role of defective lysosomal acidification.

    Science.gov (United States)

    Wolfe, Devin M; Lee, Ju-Hyun; Kumar, Asok; Lee, Sooyeon; Orenstein, Samantha J; Nixon, Ralph A

    2013-06-01

    Autophagy is a lysosomal degradative process which recycles cellular waste and eliminates potentially toxic damaged organelles and protein aggregates. The important cytoprotective functions of autophagy are demonstrated by the diverse pathogenic consequences that may stem from autophagy dysregulation in a growing number of neurodegenerative disorders. In many of the diseases associated with autophagy anomalies, it is the final stage of autophagy-lysosomal degradation that is disrupted. In several disorders, including Alzheimer's disease (AD), defective lysosomal acidification contributes to this proteolytic failure. The complex regulation of lysosomal pH makes this process vulnerable to disruption by many factors, and reliable lysosomal pH measurements have become increasingly important in investigations of disease mechanisms. Although various reagents for pH quantification have been developed over several decades, they are not all equally well suited for measuring the pH of lysosomes. Here, we evaluate the most commonly used pH probes for sensitivity and localisation, and identify LysoSensor yellow/blue-dextran, among currently used probes, as having the optimal profile of properties for measuring lysosomal pH. In addition, we review evidence that lysosomal acidification is defective in AD and extend our original findings, of elevated lysosomal pH in presenilin 1 (PS1)-deficient blastocysts and neurons, to additional cell models of PS1 and PS1/2 deficiency, to fibroblasts from AD patients with PS1 mutations, and to neurons in the PS/APP mouse model of AD. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  10. Role of oxygen defects on the magnetic properties of ultra-small Sn1-xFexO2 nanoparticles

    Science.gov (United States)

    Dodge, Kelsey; Chess, Jordan; Eixenberger, Josh; Alanko, Gordon; Hanna, Charles B.; Punnoose, Alex

    2013-05-01

    Although the role of oxygen defects in the magnetism of metal oxide semiconductors has been widely discussed, it is been difficult to directly measure the oxygen defect concentration of samples to verify this. This work demonstrates a direct correlation between the photocatalytic activity of Sn1-xFexO2 nanoparticles and their magnetic properties. For this, a series of ˜2.6 nm sized, well characterized, single-phase Sn1-xFexO2 crystallites with x = 0-0.20 were synthesized using tin acetate, urea, and appropriate amounts of iron acetate. X-ray photoelectron spectroscopy confirmed the concentration and 3+ oxidation state of the doped Fe ions. The maximum magnetic moment/Fe ion, μ, of 1.6 × 10-4 μB observed for the 0.1% Fe doped sample is smaller than the expected spin-only contribution from either high or low spin Fe3+ ions, and μ decreases with increasing Fe concentration. This behavior cannot be explained by the existing models of magnetic exchange. Photocatalytic studies of pure and Fe-doped SnO2 were used to understand the roles of doped Fe3+ ions and of the oxygen vacancies and defects. The photocatalytic rate constant k also showed an increase when SnO2 nanoparticles were doped with low concentrations of Fe3+, reaching a maximum at 0.1% Fe, followed by a rapid decrease of k for further increase in Fe%. Fe doping presumably increases the concentration of oxygen vacancies, and both Fe3+ ions and oxygen vacancies act as electron acceptors to reduce e--h+ recombination and promote transfer of electrons (and/or holes) to the nanoparticle surface, where they participate in redox reactions. This electron transfer from the Fe3+ ions to local defect density of states at the nanoparticle surface could develop a magnetic moment at the surface states and leads to spontaneous ferromagnetic ordering of the surface shell under favorable conditions. However, at higher doping levels, the same Fe3+ ions might act as recombination centers causing a decrease of both k and

  11. EPR of defects in semiconductors: past, present, future

    International Nuclear Information System (INIS)

    Watkins, G.D.

    1999-01-01

    Important physical concepts learned from early EPR studies of defects in silicon are reviewed. Highlighted are the studies of shallow effective-mass-liked donors and acceptors of deep transition element impurities, and of vacancies and interstitials. It is shown that the concepts learned in silicon translate remarkable well to the corresponding defects in the other elemental and compound semiconductors. The introduction of sensitive optical and electrical detection methods and the recent progress in single defects detection insure the continued vital role of EPR in the future

  12. The role of surface and deep-level defects on the emission of tin oxide quantum dots

    International Nuclear Information System (INIS)

    Kumar, Vinod; Kumar, Vijay; Som, S; Ntwaeaborwa, O M; Swart, H C; Neethling, J H; Lee, Mike

    2014-01-01

    This paper reports on the role of surface and deep-level defects on the blue emission of tin oxide quantum dots (SnO 2 QDs) synthesized by the solution-combustion method at different combustion temperatures. X-ray diffraction studies showed the formation of a single rutile SnO 2 phase with a tetragonal lattice structure. High resolution transmission electron microscopy studies revealed an increase in the average dot size from 2.2 to 3.6 nm with an increase of the combustion temperature from 350 to 550 °C. A decrease in the band gap value from 3.37 to 2.76 eV was observed with the increase in dot size due to the quantum confinement effect. The photoluminescence emission was measured for excitation at 325 nm and it showed a broad blue emission band for all the combustion temperatures studied. This was due to the creation of various oxygen and tin vacancies/defects as confirmed by x-ray photoelectron spectroscopy data. The origin of the blue emission in the SnO 2 QDs is discussed with the help of an energy band diagram. (paper)

  13. No significant role for beta tubulin mutations and mismatch repair defects in ovarian cancer resistance to paclitaxel/cisplatin

    International Nuclear Information System (INIS)

    Mesquita, Bárbara; Veiga, Isabel; Pereira, Deolinda; Tavares, Ana; Pinto, Isabel M; Pinto, Carla; Teixeira, Manuel R; Castedo, Sérgio

    2005-01-01

    The mechanisms of chemoresistance in ovarian cancer patients remain largely to be elucidated. Paclitaxel/cisplatin combination is the standard chemotherapeutic treatment for this disease, although some patients do not respond to therapy. Our goals were to investigate whether TUBB mutations and mismatch repair defects underlie paclitaxel and cisplatin resistance. Thirty-four patients with primary ovarian carcinomas (26 serous and eight clear cell carcinomas) treated with paclitaxel/cisplatin were analysed. TUBB exon 4 was analysed by nested PCR after a first round PCR using intronic primers. Microsatellite analysis was performed with the quasimonomorphic markers BAT 26 and BAT 34. Twenty-two of the 34 ovarian cancers (64.7%) presented residual tumour after surgery, seven of which (7/22; 31.8%) were shown to be chemoresistant (five serous and two clear cell tumours). Sequence analysis did not find any mutation in TUBB exon 4. Microsatellite instability was not detected in any of the ovarian carcinomas. We conclude that TUBB exon 4 mutations and mismatch repair defects do not play a significant role in paclitaxel/cisplatin resistance

  14. Chronic colitis due to an epithelial barrier defect: the role of kindlin-1 isoforms.

    Science.gov (United States)

    Kern, J S; Herz, C; Haan, E; Moore, D; Nottelmann, S; von Lilien, T; Greiner, P; Schmitt-Graeff, A; Opitz, O G; Bruckner-Tuderman, L; Has, C

    2007-12-01

    Kindlin-1 is an epithelium-specific phosphoprotein and focal adhesion adaptor component. Mutations in the corresponding gene (KIND1) cause Kindler syndrome (KS), which is manifested by skin blistering, poikiloderma, photosensitivity and carcinogenesis. Some patients also exhibit gastrointestinal symptoms, but it has remained unclear whether these represent a feature of Kindler syndrome or a coincidence. We examined kindlin-1 in human gastrointestinal epithelia and showed that it is involved in the aetiopathology of Kindler syndrome-associated colitis. Kindlin-1 expression was assessed by indirect immunofluorescence, western blot and RT-PCR. Kindlin-1 is expressed in oral mucosa, colon and rectum. Both the full-length 74 kDa kindlin-1 protein and a 43 kDa isoform were detected in CaCo2 cells, the latter resulting from alternative splicing. In the first months of life, patients (homozygous for null mutations) had severe intestinal involvement with haemorrhagic diarrhoea and showed morphological features of severe ulcerative colitis. Later in childhood, histopathology demonstrated focal detachment of the epithelium in all segments of the colon, chronic inflammation and mucosal atrophy. These findings define an intestinal phenotype for Kindler syndrome as a consequence of a primary epithelial barrier defect. The different clinical intestinal manifestations in Kindler syndrome patients may be explained by partial functional compensation of kindlin-1 deficiency by the intestinal isoform or by the presence of truncated mutant kindlin-1. (c) 2007 Pathological Society of Great Britain and Ireland

  15. Mesostructure of Ordered Corneal Nano-nipple Arrays: The Role of 5-7 Coordination Defects

    Science.gov (United States)

    Lee, Ken C.; Yu, Qi; Erb, Uwe

    2016-06-01

    Corneal nano-nipple structures consisting of hexagonally arranged protrusions with diameters around 200 nm have long been known for their antireflection capability and have served as biological blueprint for solar cell, optical lens and other surface designs. However, little is known about the global arrangement of these nipples on the ommatidial surface and their growth during the eye development. This study provides new insights based on the analysis of nano-nipple arrangements on the mesoscale across entire ommatidia, which has never been done before. The most important feature in the nipple structures are topological 5- and 7-fold coordination defects, which align to form dislocations and interconnected networks of grain boundaries that divide the ommatidia into crystalline domains in different orientations. Furthermore, the domain size distribution might be log-normal, and the domains demonstrate no preference in crystal orientation. Both observations suggest that the nipple growth process may be similar to the nucleation and growth mechanisms during the formation of other crystal structures. Our results are also consistent with the most recently proposed Turing-type reaction-diffusion process. In fact, we were able to produce the key structural characteristics of the nipple arrangements using Turing analysis from the nucleation to the final structure development.

  16. The roles of lesson study in the development of mathematics learning instrument based on learning trajectory

    Science.gov (United States)

    Misnasanti; Dien, C. A.; Azizah, F.

    2018-03-01

    This study is aimed to describe Lesson Study (LS) activity and its roles in the development of mathematics learning instruments based on Learning Trajectory (LT). This study is a narrative study of teacher’s experiences in joining LS activity. Data collecting in this study will use three methods such as observation, documentations, and deep interview. The collected data will be analyzed with Milles and Huberman’s model that consists of reduction, display, and verification. The study result shows that through LS activity, teachers know more about how students think. Teachers also can revise their mathematics learning instrument in the form of lesson plan. It means that LS activity is important to make a better learning instruments and focus on how student learn not on how teacher teach.

  17. Reponsive and Open Learning Environments (ROLE: Requirements, Evaluation and Reflection

    Directory of Open Access Journals (Sweden)

    Effie Lai-Chong Law

    2013-02-01

    Full Text Available Coordinating requirements engineering (RE and evaluation studies across heterogeneous technology-enhanced learning (TEL environments is deemed challenging, because each of them is situated in a specific organizational, technical and socio-cultural context. We have dealt with such challenges in the project of ROLE (http://www.role-project.eu/ in which five test-beds are involved in deploying and evaluating Personal Learning Environments (PLEs. They include Higher Education Institutions (HEIs and global enterprises in and beyond Europe, representing a range of values and assumptions. While the diversity provides fertile grounds for validating our research ideas, it poses many challenges for conducting comparison studies. In the paper, we first provide an overview of the ROLE project, focusing on its missions and aims. Next we present a Web2.0-inspired RE approach called Social Requirements Engineering (SRE. Then we depict our initial attempts to evaluate the ROLE framework and report some preliminary findings. One major outcome is that the technology adoption process must work on the basis of existing LMS, extending them with the ROLE functionality rather than embracing LMS functionality in ROLE.

  18. Learners' Perceptions of Blended Learning and the Roles and Interaction of f2f and Online Learning

    Science.gov (United States)

    Huang, Qiang

    2016-01-01

    The present study aims to probe into learners' perceptions of blended learning in relation to the respective roles of face-to-face learning (f2f learning) and online learning as well as their interaction in the blended EFL contexts. Questionnaires were used in the study to examine the attitudes of 296 university students towards a blended English…

  19. The role of NPY in learning and memory

    DEFF Research Database (Denmark)

    Gøtzsche, C. R.; Woldbye, D. P. D.

    2016-01-01

    with Y1 receptor-mediated neurogenesis could constitute necessary steps in consolidation and long-term retention of spatial memory. Altogether, NPY-induced effects on learning and memory seem to be biphasic, anatomically and temporally differential, and in support of a modulatory role of NPY at keeping......High levels of NPY expression in brain regions important for learning and memory together with its neuromodulatory and neurotrophic effects suggest a regulatory role for NPY in memory processes. Therefore it is not surprising that an increasing number of studies have provided evidence for NPY...... acting as a modulator of neuroplasticity, neurotransmission, and memory. Here these results are presented in relation to the types of memory affected by NPY and its receptors. NPY can exert both inhibitory and stimulatory effects on memory, depending on memory type and phase, dose applied, brain region...

  20. Resident burnout: evaluating the role of the learning environment.

    Science.gov (United States)

    van Vendeloo, Stefan N; Godderis, Lode; Brand, Paul L P; Verheyen, Kees C P M; Rowell, Suria A; Hoekstra, Harm

    2018-03-27

    Although burnout is viewed as a syndrome rooted in the working environment and organizational culture, the role of the learning environment in the development of resident burnout remains unclear. We aimed to evaluate the association between burnout and the learning environment in a cohort of Belgian residents. We conducted a cross-sectional online survey among residents in a large university hospital in Belgium. We used the Dutch version of the Maslach Burnout Inventory (UBOS-C) to assess burnout and the Dutch Residency Educational Climate Test (D-RECT) to assess the learning environment. A total of 236 residents (29 specialties) completed the survey (response rate 34.6%), of which 98 (41.5%) met standard criteria for burnout. After multivariate regression analysis adjusting for hours worked per week, quality of life and satisfaction with work-life balance, we found an inverse association between D-RECT scores and the risk of burnout (adjusted odds ratio; 0.47 for each point increase in D-RECT score; 95% CI, 0.23 - 0.95; p = 0.01). Resident burnout is highly prevalent in our cohort of Belgian residents. Our results suggest that the learning environment plays an important role in reducing the risk of burnout among residents.

  1. Dendritic cells are defective in breast cancer patients: a potential role for polyamine in this immunodeficiency

    International Nuclear Information System (INIS)

    Gervais, Alban; Levêque, Jean; Bouet-Toussaint, Françoise; Burtin, Florence; Lesimple, Thierry; Sulpice, Laurent; Patard, Jean-Jacques; Genetet, Noelle; Catros-Quemener, Véronique

    2005-01-01

    Dendritic cells (DCs) are antigen-presenting cells that are currently employed in cancer clinical trials. However, it is not clear whether their ability to induce tumour-specific immune responses when they are isolated from cancer patients is reduced relative to their ability in vivo. We determined the phenotype and functional activity of DCs from cancer patients and investigated the effect of putrescine, a polyamine molecule that is released in large amounts by cancer cells and has been implicated in metastatic invasion, on DCs. The IL-4/GM-CSF (granulocyte–macrophage colony-stimulating factor) procedure for culturing blood monocyte-derived DCs was applied to cells from healthy donors and patients (17 with breast, 7 with colorectal and 10 with renal cell carcinoma). The same peroxide-treated tumour cells (M74 cell line) were used for DC pulsing. We investigated the effects of stimulation of autologous lymphocytes by DCs pulsed with treated tumour cells (DC-Tu), and cytolytic activity of T cells was determined in the same target cells. Certain differences were observed between donors and breast cancer patients. The yield of DCs was dramatically weaker, and expression of MHC class II was lower and the percentage of HLA-DR - Lin - cells higher in patients. Whatever combination of maturating agents was used, expression of markers of mature DCs was significantly lower in patients. Also, DCs from patients exhibited reduced ability to stimulate cytotoxic T lymphocytes. After DC-Tu stimulation, specific cytolytic activity was enhanced by up to 40% when DCs were from donors but only up to 10% when they were from patients. IFN-γ production was repeatedly found to be enhanced in donors but not in patients. By adding putrescine to DCs from donors, it was possible to enhance the HLA-DR - Lin - cell percentage and to reduce the final cytolytic activity of lymphocytes after DC-Tu stimulation, mimicking defective DC function. These putrescine-induced deficiencies were reversed

  2. The role of culture in perceptual learning styles

    OpenAIRE

    حسینی فاطمی ، پیشقدم حسینی فاطمی ، پیشقدم

    2009-01-01

    The major aim of this article is to determine the role of culture in perceptual learning style (PLS) preferences of Iranian English learners, in order to minimize teacher-student style conflict in the classroom. To do this, 400 university students from different fields of study were selected from Allameh Tabatabaee University in Tehran, Ferdowsi University of Mashhad and Mashhad University of Medical Sciences. The subjects were asked to answer Reid’s questionnaire (1987) which was designed to...

  3. [Progress on metaplasticity and its role in learning and memory].

    Science.gov (United States)

    Wang, Shao-Li; Lu, Wei

    2016-08-25

    Long-term potentiation (LTP) and long-term depression (LTD) are two major forms of synaptic plasticity that are widely considered as important cellular models of learning and memory. Metaplasticity is defined as the plasticity of synaptic plasticity and thus is an advanced form of plasticity. The history of synaptic activity can affect the subsequent synaptic plasticity induction. Therefore, it is important to study metaplasticity to explore new mechanisms underlying various brain functions including learning and memory. Since the concept of metaplasticity was proposed, it has aroused widespread concerns and attracted numerous researchers to dig more details on this topic. These new-found experimental phenomena and cellular mechanisms have established the basis of theoretical studies on metaplasticity. In recent years, researchers have found that metaplasticity can not only affect the synaptic plasticity, but also regulate the neural network to encode specific content and enhance the learning and memory. These findings have greatly enriched our knowledge on plasticity and opened a new route to study the mechanism of learning and memory. In this review, we discuss the recent progress on metaplasticity on following three aspects: (1) the molecular mechanisms of metaplasticity; (2) the role of metaplasticity in learning and memory; and (3) the outlook of future study on metaplasticity.

  4. A Study on the Role of Drama in Learning Mathematics

    Directory of Open Access Journals (Sweden)

    Elahe Masoum

    2013-08-01

    Full Text Available Present educational systems needs modern strategies for teaching and learning. Mathematics education has to change for students in elementary schools. One of the modern strategies, it is drama activities. The drama is as empirical aspect of learning. The student may learn from what they are doing in drama. They are so active instead having a passive shape in drama, in fact, students are learning, finding experiences and new paths from drama as well. The students could find its capabilities, recommendations and strength-weakness points through the different drama. This study is looking to investigate the role of drama so that have a better understanding of mathematical concepts in Zahedan's girly elementary students (2011-12. This research is used on 36 three grade students through quasi-experiment method. The emerging results clearly showed that using drama in mathematics education has been better results against the traditional teaching. Then it seems that cited method is suitable for elementary students to learn mathematical concepts.

  5. A fundamental role for context in instrumental learning and extinction.

    Science.gov (United States)

    Bouton, Mark E; Todd, Travis P

    2014-05-01

    The purpose of this article is to review recent research that has investigated the effects of context change on instrumental (operant) learning. The first part of the article discusses instrumental extinction, in which the strength of a reinforced instrumental behavior declines when reinforcers are withdrawn. The results suggest that extinction of either simple or discriminated operant behavior is relatively specific to the context in which it is learned: As in prior studies of Pavlovian extinction, ABA, ABC, and AAB renewal effects can all be observed. Further analysis supports the idea that the organism learns to refrain from making a specific response in a specific context, or in more formal terms, an inhibitory context-response association. The second part of the article then discusses research suggesting that the context also controls instrumental behavior before it is extinguished. Several experiments demonstrate that a context switch after either simple or discriminated operant training causes a decrement in the strength of the response. Over a range of conditions, the animal appears to learn a direct association between the context and the response. Under some conditions, it can also learn a hierarchical representation of context and the response-reinforcer relation. Extinction is still more context-specific than conditioning, as indicated by ABC and AAB renewal. Overall, the results establish that the context can play a significant role in both the acquisition and extinction of operant behavior. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Exploring Effects of Different Roles on Using an E-learning Service

    Directory of Open Access Journals (Sweden)

    Yang H.J.

    2016-01-01

    Full Text Available The purpose of this study was to explore effects of different roles on learning satisfaction. For better hosting a e-learning service, there is a need to understand user’s satisfaction of the learning service. Data was collected from an on-line learning system. Based upon course learning activities, each course was assign to a certain role for the learner. There are six types of learning role from all course. 1 Reporter, 2 Listener, 3 Researcher, 4 Reporting Listener, 5 Reporting Researcher, 6 Report Listen Researcher; One-way ANOVA procedure was applied to exploring whether the role difference affects users satisfaction. According to the significant level less than .05, it was concluded that learning satisfaction of different roles are significant different. On the other word, learning roles affect users’ learning satisfaction.

  7. Defect production in ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Zinkle, S.J. [Oak Ridge National Lab., TN (United States); Kinoshita, C. [Kyushu Univ. (Japan)

    1997-08-01

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si{sub 3}N{sub 4}), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed.

  8. Learning Behaviour and Learning Outcomes: The Roles for Social Influence and Field of Study

    Science.gov (United States)

    Smyth, Lillian; Mavor, Kenneth I.; Platow, Michael J.

    2017-01-01

    Research has demonstrated a significant role of discipline social identification in predicting learning approaches, even controlling for individual differences. Smyth et al. ("Educ Psychol" 35(1):53-72, 2015. doi:10.1080/01443410.2013.822962) suggest that learners share discipline-based social identifications, and that this…

  9. Achieving DFT accuracy with a machine-learning interatomic potential: Thermomechanics and defects in bcc ferromagnetic iron

    Science.gov (United States)

    Dragoni, Daniele; Daff, Thomas D.; Csányi, Gábor; Marzari, Nicola

    2018-01-01

    We show that the Gaussian Approximation Potential (GAP) machine-learning framework can describe complex magnetic potential energy surfaces, taking ferromagnetic iron as a paradigmatic challenging case. The training database includes total energies, forces, and stresses obtained from density-functional theory in the generalized-gradient approximation, and comprises approximately 150,000 local atomic environments, ranging from pristine and defected bulk configurations to surfaces and generalized stacking faults with different crystallographic orientations. We find the structural, vibrational, and thermodynamic properties of the GAP model to be in excellent agreement with those obtained directly from first-principles electronic-structure calculations. There is good transferability to quantities, such as Peierls energy barriers, which are determined to a large extent by atomic configurations that were not part of the training set. We observe the benefit and the need of using highly converged electronic-structure calculations to sample a target potential energy surface. The end result is a systematically improvable potential that can achieve the same accuracy of density-functional theory calculations, but at a fraction of the computational cost.

  10. THE ROLE AND PLACE OF DISTANCE LEARNING IN E-LEARNING

    Directory of Open Access Journals (Sweden)

    Vladyslav Velychko

    2016-11-01

    Full Text Available The article discusses the role and place of distance education in electronic learning. The implementation of such important components as e-learning and e-education in the education system is an important tool to achieve the objectives of global education and requires specific knowledge. Teaching staff of educational institutions must learn new teaching tools such as cloud, Virtual Reality, Augmented Reality, mobile technology, Internet technology, designing distance learning courses, etc., or increase the level of this category. We consider the relevance and benefits of the use of distance education in electronic learning, and the need of its implementation at all levels of the educational process and basic steps for it. Distance learning courses have several types that differ in the degree of farness, individualization and its efficiency: "educational institution → Internet" (includes full-time training using Internet resources, videlicet to find things on the Internet and communicate with other network users; "educational institution → Internet → educational institution" (used in the full-time study, but has occasional problem with the mandatory use of the Internet; "the one who learns → Internet → the one who teaches" (distance learning complements the full-time education, it has an episodic format as consultations in a case of need; "the one who learns → Internet → Center" (full-time complement of training and has additional opportunities to strengthen the disclosure of a special creativity; "the one who learns → Internet" (it can serve as an additional training to full-time education, but can also be transformed into an independent "institution" that takes into account individual needs and capabilities of the individual and a flexible adjustment under her needs and interests using the educational resources on the Internet . There has been proved the necessity of mastering of the teaching staff of educational institutions

  11. Role of tissue-engineered artificial tendon in healing of a large Achilles tendon defect model in rabbits.

    Science.gov (United States)

    Moshiri, Ali; Oryan, Ahmad; Meimandi-Parizi, Abdolhamid

    2013-09-01

    Treatment of large Achilles tendon defects is technically demanding. Tissue engineering is an option. We constructed a collagen-based artificial tendon, covered it with a polydioxanon (PDS) sheath, and studied the role of this bioimplant on experimental tendon healing in vivo. A 2-cm tendon gap was created in the left Achilles tendon of rabbits (n = 120). The animals were randomly divided into 3 groups: control (no implant), treated with tridimensional-collagen, and treated with tridimensional-collagen-bidimensional-PDS implants. Each group was divided into 2 subgroups of 60 and 120 days postinjury (DPI). Another 50 pilot animals were used to study the host-implant interaction. Physical activity of the animals was scored and ultrasonographic and bioelectrical characteristics of the injured tendons were investigated weekly. After euthanasia, macro, micro, and nano morphologies and biophysical and biomechanical characteristics of the healing tendons were studied. Treatment improved function of the animals, time dependently. At 60 and 120 DPI, the treated tendons showed significantly higher maximum load, yield, stiffness, stress, and modulus of elasticity compared with controls. The collagen implant induced inflammation and absorbed the migrating fibroblasts in the defect area. By its unique architecture, it aligned the fibroblasts and guided their proliferation and collagen deposition along the stress line of the tendon and resulted in improved collagen density, micro-amp, micro-ohm, water uptake, and delivery of the regenerated tissue. The PDS-sheath covering amplified these characteristics. The implants were gradually absorbed and replaced by a new tendon. Minimum amounts of peritendinous adhesion, muscle atrophy, and fibrosis were observed in the treated groups. Some remnants of the implants were preserved and accepted as a part of the new tendon. The implants were cytocompatible, biocompatible, biodegradable, and effective in tendon healing and regeneration. This

  12. The role of nitric oxide in muscle fibers with oxidative phosphorylation defects

    International Nuclear Information System (INIS)

    Tengan, Celia H.; Kiyomoto, Beatriz H.; Godinho, Rosely O.; Gamba, Juliana; Neves, Afonso C.; Schmidt, Beny; Oliveira, Acary S.B.; Gabbai, Alberto A.

    2007-01-01

    NO has been pointed as an important player in the control of mitochondrial respiration, especially because of its inhibitory effect on cytochrome c oxidase (COX). However, all the events involved in this control are still not completely elucidated. We demonstrate compartmentalized abnormalities on nitric oxide synthase (NOS) activity on muscle biopsies of patients with mitochondrial diseases. NOS activity was reduced in the sarcoplasmic compartment in COX deficient fibers, whereas increased activity was found in the sarcolemma of fibers with mitochondrial proliferation. We observed increased expression of neuronal NOS (nNOS) in patients and a correlation between nNOS expression and mitochondrial content. Treatment of skeletal muscle culture with an NO donor induced an increase in mitochondrial content. Our results indicate specific roles of NO in compensatory mechanisms of muscle fibers with mitochondrial deficiency and suggest the participation of nNOS in the signaling process of mitochondrial proliferation in human skeletal muscle

  13. The role of reference in cross-situational word learning.

    Science.gov (United States)

    Wang, Felix Hao; Mintz, Toben H

    2018-01-01

    Word learning involves massive ambiguity, since in a particular encounter with a novel word, there are an unlimited number of potential referents. One proposal for how learners surmount the problem of ambiguity is that learners use cross-situational statistics to constrain the ambiguity: When a word and its referent co-occur across multiple situations, learners will associate the word with the correct referent. Yu and Smith (2007) propose that these co-occurrence statistics are sufficient for word-to-referent mapping. Alternative accounts hold that co-occurrence statistics alone are insufficient to support learning, and that learners are further guided by knowledge that words are referential (e.g., Waxman & Gelman, 2009). However, no behavioral word learning studies we are aware of explicitly manipulate subjects' prior assumptions about the role of the words in the experiments in order to test the influence of these assumptions. In this study, we directly test whether, when faced with referential ambiguity, co-occurrence statistics are sufficient for word-to-referent mappings in adult word-learners. Across a series of cross-situational learning experiments, we varied the degree to which there was support for the notion that the words were referential. At the same time, the statistical information about the words' meanings was held constant. When we overrode support for the notion that words were referential, subjects failed to learn the word-to-referent mappings, but otherwise they succeeded. Thus, cross-situational statistics were useful only when learners had the goal of discovering mappings between words and referents. We discuss the implications of these results for theories of word learning in children's language acquisition. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. A Novel Role for CSRP1 in a Lebanese Family with Congenital Cardiac Defects

    Directory of Open Access Journals (Sweden)

    Amina Kamar

    2017-12-01

    Full Text Available Despite an obvious role for consanguinity in congenital heart disease (CHD, most studies fail to document a monogenic model of inheritance except for few cases. We hereby describe a first-degree cousins consanguineous Lebanese family with 7 conceived children: 2 died in utero of unknown causes, 3 have CHD, and 4 have polydactyly. The aim of the study is to unveil the genetic variant(s causing these phenotypes using next generation sequencing (NGS technology. Targeted exome sequencing identified a heterozygous duplication in CSRP1 which leads to a potential frameshift mutation at position 154 of the protein. This mutation is inherited from the father, and segregates only with the CHD phenotype. The in vitro characterization demonstrates that the mutation dramatically abrogates its transcriptional activity over cardiac promoters like NPPA. In addition, it differentially inhibits the physical association of CSRP1 with SRF, GATA4, and with the newly described partner herein TBX5. Whole exome sequencing failed to show any potential variant linked to polydactyly, but revealed a novel missense mutation in TRPS1. This mutation is inherited from the healthy mother, and segregating only with the cardiac phenotype. Both TRPS1 and CSRP1 physically interact, and the mutations in each abrogate their partnership. Our findings add fundamental knowledge into the molecular basis of CHD, and propose the di-genic model of inheritance as responsible for such malformations.

  15. Early Retinal Defects in Fmr1−/y Mice: Toward a Critical Role of Visual Dys-Sensitivity in the Fragile X Syndrome Phenotype?

    Directory of Open Access Journals (Sweden)

    Olivier Perche

    2018-04-01

    Full Text Available Fragile X Syndrome (FXS is caused by a deficiency in Fragile X Mental Retardation Protein (FMRP leading to global sensorial abnormalities, among which visual defects represent a critical part. These visual defects are associated with cerebral neuron immaturity especially in the primary visual cortex. However, we recently demonstrated that retinas of adult Fmr1−/y mice, the FXS murine model, present molecular, cellular and functional alterations. However, no data are currently available on the evolution pattern of such defects. As retinal stimulation through Eye Opening (EO is a crucial signal for the cerebral visual system maturation, we questioned the precocity of molecular and functional retinal phenotype. To answer this question, we studied the retinal molecular phenotype of Fmr1−/y mice before EO until adult age and the consequences of the retinal loss of Fmrp on retinal function in young and adult mice. We showed that retinal molecular defects are present before EO and remain stable at adult age, leading to electrophysiological impairments without any underlying structural changes. We underlined that loss of Fmrp leads to a wide range of defects in the retina, settled even before EO. Our work demonstrates a critical role of the sensorial dysfunction in the Fmr1−/y mice overall phenotype, and provides evidence that altered peripheral perception is a component of the sensory processing defect in FXS conditions.

  16. Early Retinal Defects in Fmr1-/y Mice: Toward a Critical Role of Visual Dys-Sensitivity in the Fragile X Syndrome Phenotype?

    Science.gov (United States)

    Perche, Olivier; Felgerolle, Chloé; Ardourel, Maryvonne; Bazinet, Audrey; Pâris, Arnaud; Rossignol, Rafaëlle; Meyer-Dilhet, Géraldine; Mausset-Bonnefont, Anne-Laure; Hébert, Betty; Laurenceau, David; Montécot-Dubourg, Céline; Menuet, Arnaud; Bizot, Jean-Charles; Pichon, Jacques; Ranchon-Cole, Isabelle; Briault, Sylvain

    2018-01-01

    Fragile X Syndrome (FXS) is caused by a deficiency in Fragile X Mental Retardation Protein (FMRP) leading to global sensorial abnormalities, among which visual defects represent a critical part. These visual defects are associated with cerebral neuron immaturity especially in the primary visual cortex. However, we recently demonstrated that retinas of adult Fmr1 -/y mice, the FXS murine model, present molecular, cellular and functional alterations. However, no data are currently available on the evolution pattern of such defects. As retinal stimulation through Eye Opening (EO) is a crucial signal for the cerebral visual system maturation, we questioned the precocity of molecular and functional retinal phenotype. To answer this question, we studied the retinal molecular phenotype of Fmr1 -/y mice before EO until adult age and the consequences of the retinal loss of Fmrp on retinal function in young and adult mice. We showed that retinal molecular defects are present before EO and remain stable at adult age, leading to electrophysiological impairments without any underlying structural changes. We underlined that loss of Fmrp leads to a wide range of defects in the retina, settled even before EO. Our work demonstrates a critical role of the sensorial dysfunction in the Fmr1 -/y mice overall phenotype, and provides evidence that altered peripheral perception is a component of the sensory processing defect in FXS conditions.

  17. Early Retinal Defects in Fmr1−/y Mice: Toward a Critical Role of Visual Dys-Sensitivity in the Fragile X Syndrome Phenotype?

    Science.gov (United States)

    Perche, Olivier; Felgerolle, Chloé; Ardourel, Maryvonne; Bazinet, Audrey; Pâris, Arnaud; Rossignol, Rafaëlle; Meyer-Dilhet, Géraldine; Mausset-Bonnefont, Anne-Laure; Hébert, Betty; Laurenceau, David; Montécot-Dubourg, Céline; Menuet, Arnaud; Bizot, Jean-Charles; Pichon, Jacques; Ranchon-Cole, Isabelle; Briault, Sylvain

    2018-01-01

    Fragile X Syndrome (FXS) is caused by a deficiency in Fragile X Mental Retardation Protein (FMRP) leading to global sensorial abnormalities, among which visual defects represent a critical part. These visual defects are associated with cerebral neuron immaturity especially in the primary visual cortex. However, we recently demonstrated that retinas of adult Fmr1−/y mice, the FXS murine model, present molecular, cellular and functional alterations. However, no data are currently available on the evolution pattern of such defects. As retinal stimulation through Eye Opening (EO) is a crucial signal for the cerebral visual system maturation, we questioned the precocity of molecular and functional retinal phenotype. To answer this question, we studied the retinal molecular phenotype of Fmr1−/y mice before EO until adult age and the consequences of the retinal loss of Fmrp on retinal function in young and adult mice. We showed that retinal molecular defects are present before EO and remain stable at adult age, leading to electrophysiological impairments without any underlying structural changes. We underlined that loss of Fmrp leads to a wide range of defects in the retina, settled even before EO. Our work demonstrates a critical role of the sensorial dysfunction in the Fmr1−/y mice overall phenotype, and provides evidence that altered peripheral perception is a component of the sensory processing defect in FXS conditions. PMID:29681800

  18. TEACHER ROLE IN FORMATION POLITENESS OF STUDENT LEARNING PROCESS

    Directory of Open Access Journals (Sweden)

    Wahyuni Oktavia

    2016-09-01

    Full Text Available Language as a communication tool has an important role in human interaction. Language can be used to convey ideas, ideas, feelings, desires, and so forth to others. To be able to communicate well certainly should be able to adjust the language used. One of the main functions of communication is to maintain the continuity of the relationship between the narrator and hearer. Language is an important pillar in the formation of character, in addition to religious education and moral education. In education, teachers must have pedagogical, professional, personal, and social. Teachers who have a good competence speech acts certainly have a good and well mannered to students. In the learning process, teachers and students communicate in give and receive course materials. The learning process is certainly not only provides knowledge alone, but give the values of character to students. In this case, the teacher must have a principle that must be controlled properly, correctly and precisely. Thus, teachers are expected to master the communication and understanding the principles of politeness in speaking well and correctly. The goal is a description of a form of politeness in the learning process. This research is a descriptive study which seeks to describe a form of politeness in the learning process. Data collection method used is the method refer to the data collection techniques are 1 recording technique using a tape recorder, and 2 technical note on the data card. Furthermore, methods of data analysis using pragmatic frontier.

  19. Optical properties of GaSb(001)-c(2 x 6): The role of surface antisite defects

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Conor; Del Sole, Rodolfo [Department of Physics, CNR-INFM-SMC, Roma (Italy); European Theoretical Spectroscopy Facility (ETSF), University of Rome ' ' Tor Vergata' ' , Roma (Italy); Magri, Rita [Centro S3-CNR-Istituto di Nanoscienze, Modena (Italy); Department of Physics, University of Modena and Reggio Emilia, Modena (Italy)

    2010-08-15

    We consider the formation of surface antisite defects on a previously proposed model for the GaSb(001)-c(2 x 6) surface. Based on ab initio total energy calculations, we show how these defects stabilize the otherwise metallic surface and how their formation is driven by the excess charge associated with the Sb-rich surface conditions. The surface-sensitive optical technique of reflectance anisotropy spectroscopy is shown to be crucial for detecting the defects, and computation of spectra yields a good agreement with experiment when defects are included in the surface reconstruction. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  20. Examining the Roles of Blended Learning Approaches in Computer-Supported Collaborative Learning (CSCL) Environments: A Delphi Study

    Science.gov (United States)

    So, Hyo-Jeong; Bonk, Curtis J.

    2010-01-01

    In this study, a Delphi method was used to identify and predict the roles of blended learning approaches in computer-supported collaborative learning (CSCL) environments. The Delphi panel consisted of experts in online learning from different geographic regions of the world. This study discusses findings related to (a) pros and cons of blended…

  1. On the Role of Minor Branches, Energy Dissipation, and Small Defects in the Transient Response of Transmission Mains

    Directory of Open Access Journals (Sweden)

    Silvia Meniconi

    2018-02-01

    Full Text Available In the last decades several reliable technologies have been proposed for fault detection in water distribution networks (DNs, whereas there are some limitations for transmission mains (TMs. For TM inspection, the most common fault detection technologies are of inline types—with sensors inserted into the pipelines—and then more expensive with respect to those used in DNs. An alternative to in-line sensors is given by transient test-based techniques (TTBTs, where pressure waves are injected in pipes “to explore” them. On the basis of the results of some tests, this paper analyses the relevance of the system configuration, energy dissipation phenomena, and pipe material characteristics in the transient behavior of a real TM. With this aim, a numerical model has been progressively refined not only in terms of the governing equations but also by including a more and more realistic representation of the system layout and taking into account the actual functioning conditions. As a result, the unexpected role of the minor branches—i.e., pipes with a length smaller than the 1% of the length of the main pipe—is pointed out and a preliminary criterion for the system skeletonization is offered. Moreover, the importance of both unsteady friction and viscoelasticity is evaluated as well as the remarkable effects of small defects is highlighted.

  2. Characterization of SMAD3 Gene Variants for Possible Roles in Ventricular Septal Defects and Other Congenital Heart Diseases.

    Directory of Open Access Journals (Sweden)

    Fei-Feng Li

    Full Text Available Nodal/TGF signaling pathway has an important effect at early stages of differentiation of human embryonic stem cells in directing them to develop into different embryonic lineages. SMAD3 is a key intracellular messenger regulating factor in the Nodal/TGF signaling pathway, playing important roles in embryonic and, particularly, cardiovascular system development. The aim of this work was to find evidence on whether SMAD3 variations might be associated with ventricular septal defects (VSD or other congenital heart diseases (CHD.We sequenced the SMAD3 gene for 372 Chinese Han CHD patients including 176 VSD patients and evaluated SNP rs2289263, which is located before the 5'UTR sequence of the gene. The statistical analyses were conducted using Chi-Square Tests as implemented in SPSS (version 13.0. The Hardy-Weinberg equilibrium test of the population was carried out using the online software OEGE.Three heterozygous variants in SMAD3 gene, rs2289263, rs35874463 and rs17228212, were identified. Statistical analyses showed that the rs2289263 variant located before the 5'UTR sequence of SMAD3 gene was associated with the risk of VSD (P value=0.013 <0.05.The SNP rs2289263 in the SMAD3 gene is associated with VSD in Chinese Han populations.

  3. An interactive machine-learning approach for defect detection in computed tomogaraphy (CT) images of hardwood logs

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt; Philip A. Araman

    2005-01-01

    This paper describes recent progress in the analysis of computed tomography (CT) images of hardwood logs. The long-term goal of the work is to develop a system that is capable of autonomous (or semiautonomous) detection of internal defects, so that log breakdown decisions can be optimized based on defect locations. The problem is difficult because wood exhibits large...

  4. Birth Defects

    Science.gov (United States)

    A birth defect is a problem that happens while a baby is developing in the mother's body. Most birth defects happen during the first 3 months of ... in the United States is born with a birth defect. A birth defect may affect how the ...

  5. The Role of Higher Education in Promoting Lifelong Learning. UIL Publication Series on Lifelong Learning Policies and Strategies: No. 3

    Science.gov (United States)

    Yang, Jin, Ed.; Schneller, Chripa, Ed.; Roche, Stephen, Ed.

    2015-01-01

    There is no doubt that universities have a vital role to play in promoting lifelong learning. This publication presents possible ways of expanding and transforming higher education to facilitate lifelong learning in different socio-economic contexts. Nine articles address the various dimensions of the role of higher education in promoting lifelong…

  6. What Role do Metaphors Play in Game-Based Learning Processes?

    DEFF Research Database (Denmark)

    Henriksen, Thomas Duus

    2014-01-01

    This chapter explores the role played by metaphors in learning games and game-based learning processes. The aim is to contribute better understanding of the mechanisms of how such games contribute to learning and learning transfer. On the basis of an analytical strategy that emphasises metaphors...... as storylines, actors, acts and movement, three learning games are analysed in order to understand how learning emerges in association to game-embedded metaphors. As shown in this chapter, metaphors seem to play a profound role in game-based learning, both by providing participants with a suitcase containing...

  7. Efficacy of Role Play in Concert with Lecture to Enhance Student Learning of Immunology

    Directory of Open Access Journals (Sweden)

    Samantha L. Elliott

    2010-11-01

    Full Text Available Despite numerous reports that active learning increases student understanding, many barriers still exist that prevent faculty from shedding the traditional passive lecture and adopting active learning strategies in the classroom. This study looks at the use of role play as an active learning technique to convey new material, or as reinforcement to traditional lecture. A pre- and post-test survey was utilized to determine student learning gains, along with an anonymous survey to determine student attitudes about role play. Student learning gains are similar regardless of class size, role-playing participation or learning style, and reflect an increase in lower order cognition. Attitudes and learning gains indicate role play is preferable as a reinforcement technique, although the order does not matter if both lecture and role play are utilized to convey information. These data provide insight into the best practices of role-playing implementation in concert with traditional lecture format.

  8. Unpacking the Roles of the Facilitator in Higher Education Professional Learning Communities

    Science.gov (United States)

    Margalef, Leonor; Pareja Roblin, Natalie

    2016-01-01

    Facilitators are central for the success of professional learning communities (PLCs). Yet, their specific roles in supporting teacher learning remain still largely underexplored. To address this gap, the current multiple case study examines the roles of 4 university PLC facilitators, the strategies they used to support teacher learning, and the…

  9. SME Innovation and Learning: The Role of Networks and Crisis Events

    Science.gov (United States)

    Saunders, Mark N. K.; Gray, David E; Goregaokar, Harshita

    2014-01-01

    Purpose: The purpose of this paper is to contribute to the literature on innovation and entrepreneurial learning by exploring how SMEs learn and innovate, how they use both formal and informal learning and in particular the role of networks and crisis events within their learning experience. Design/methodology/approach: Mixed method study,…

  10. Potential Role of Honey in Learning and Memory

    Directory of Open Access Journals (Sweden)

    Zahiruddin Othman

    2015-04-01

    Full Text Available The composition and physicochemical properties of honey are variable depending on its floral source and often named according to the geographical location. The potential medicinal benefits of Tualang honey, a multifloral jungle honey found in Malaysia, have recently been attracting attention because of its reported beneficial effects in various diseases. This paper reviews the effects of honey, particularly Tualang honey, on learning and memory. Information regarding the effects of Tualang honey on learning and memory in human as well as animal models is gleaned to hypothesize its underlying mechanisms. These studies show that Tualang honey improves morphology of memory-related brain areas, reduces brain oxidative stress, increases brain-derived neurotrophic factor (BDNF and acetylcholine (ACh concentrations, and reduces acetylcholinesterase (AChE in the brain homogenates. Its anti-inflammatory roles in reducing inflammatory trigger and microglial activation have yet to be investigated. It is hypothesized that the improvement in learning and memory following Tualang honey supplementation is due to the significant improvement in brain morphology and enhancement of brain cholinergic system secondary to reduction in brain oxidative damage and/or upregulation of BDNF concentration. Further studies are imperative to elucidate the molecular mechanism of actions.

  11. Simulation modelling: educational development roles for learning technologists

    Directory of Open Access Journals (Sweden)

    David Riley

    2002-12-01

    Full Text Available Simulation modelling was in the mainstream of CAL development in the 1980s when the late David Squires introduced this author to the Dynamic Modelling System. Since those early days, it seems that simulation modelling has drifted into a learning technology backwater to become a member of Laurillard's underutilized, 'adaptive and productive' media. Referring to her Conversational Framework, Laurillard constructs a pedagogic case for modelling as a productive student activity but provides few references to current practice and available resources. This paper seeks to complement her account by highlighting the pioneering initiatives of the Computers in the Curriculum Project and more recent developments in systems modelling within geographic and business education. The latter include improvements to system dynamics modelling programs such as STELLA®, the publication of introductory textbooks, and the emergence of online resources. The paper indicates several ways in which modelling activities may be approached and identifies some educational development roles for learning technologists. The paper concludes by advocating simulation modelling as an exemplary use of learning technologies - one that realizes their creative-transformative potential.

  12. The role of NPY in learning and memory.

    Science.gov (United States)

    Gøtzsche, C R; Woldbye, D P D

    2016-02-01

    High levels of NPY expression in brain regions important for learning and memory together with its neuromodulatory and neurotrophic effects suggest a regulatory role for NPY in memory processes. Therefore it is not surprising that an increasing number of studies have provided evidence for NPY acting as a modulator of neuroplasticity, neurotransmission, and memory. Here these results are presented in relation to the types of memory affected by NPY and its receptors. NPY can exert both inhibitory and stimulatory effects on memory, depending on memory type and phase, dose applied, brain region, and NPY receptor subtypes. Thus NPY act as a resilience factor by impairing associative implicit memory after stressful and aversive events, as evident in models of fear conditioning, presumably via Y1 receptors in the amygdala and prefrontal cortex. In addition, NPY impairs acquisition but enhances consolidation and retention in models depending on spatial and discriminative types of associative explicit memory, presumably involving Y2 receptor-mediated regulations of hippocampal excitatory transmission. Moreover, spatial memory training leads to increased hippocampal NPY gene expression that together with Y1 receptor-mediated neurogenesis could constitute necessary steps in consolidation and long-term retention of spatial memory. Altogether, NPY-induced effects on learning and memory seem to be biphasic, anatomically and temporally differential, and in support of a modulatory role of NPY at keeping the system in balance. Obtaining further insight into memory-related effects of NPY could inspire the engineering of new therapeutics targeting diseases where impaired learning and memory are central elements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Elastic and failure response of imperfect three-dimensional metallic lattices: the role of geometric defects induced by Selective Laser Melting

    Science.gov (United States)

    Liu, Lu; Kamm, Paul; García-Moreno, Francisco; Banhart, John; Pasini, Damiano

    2017-10-01

    This paper examines three-dimensional metallic lattices with regular octet and rhombicuboctahedron units fabricated with geometric imperfections via Selective Laser Sintering. We use X-ray computed tomography to capture morphology, location, and distribution of process-induced defects with the aim of studying their role in the elastic response, damage initiation, and failure evolution under quasi-static compression. Testing results from in-situ compression tomography show that each lattice exhibits a distinct failure mechanism that is governed not only by cell topology but also by geometric defects induced by additive manufacturing. Extracted from X-ray tomography images, the statistical distributions of three sets of defects, namely strut waviness, strut thickness variation, and strut oversizing, are used to develop numerical models of statistically representative lattices with imperfect geometry. Elastic and failure responses are predicted within 10% agreement from the experimental data. In addition, a computational study is presented to shed light into the relationship between the amplitude of selected defects and the reduction of elastic properties compared to their nominal values. The evolution of failure mechanisms is also explained with respect to strut oversizing, a parameter that can critically cause failure mode transitions that are not visible in defect-free lattices.

  14. Nonlinear X-ray production of defect spins in vitreous SiO2: the roles of creation and activation

    International Nuclear Information System (INIS)

    Galeener, F.L.; Kerwin, D.B.; Miller, A.J.

    1992-01-01

    The dependence of spin concentration on X-ray dose is shown to be nonlinear in distinctive ways for the three most common defect structures in vitreous SiO 2 . We fit the data with a model invoking two concurrent simple processes: creation of new defects and activation of preexisting ones. The resultant fit parameters show dependencies on hydroxyl concentration and fictive temperature that shed new light on the processes, the defects, their origins and the radiation hardness of v-SiO 2 . (author)

  15. "The Learning Sticks": Reflections on a Case Study of Role-Playing for Sustainability

    Science.gov (United States)

    Gordon, Sue; Thomas, Ian

    2018-01-01

    Use of role-plays to develop deep student-learning has many advocates. Role-play is a powerful approach for learning that develops relevant skills in a range of disciplines and situations. In Higher Education, sustainability programmes role-play pedagogy appears to have great relevance for developing the competencies that these graduates will…

  16. Possible role of mtDNA depletion and respiratory chain defects in aristolochic acid I-induced acute nephrotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Zhenzhou, E-mail: jiangcpu@yahoo.com.cn; Bao, Qingli, E-mail: bao_ql@126.com; Sun, Lixin, E-mail: slxcpu@126.com; Huang, Xin, E-mail: huangxinhx66@sohu.com; Wang, Tao, E-mail: wangtao1331@126.com; Zhang, Shuang, E-mail: cat921@sina.com; Li, Han, E-mail: hapo1101@163.com; Zhang, Luyong, E-mail: lyzhang@cpu.edu.cn

    2013-01-15

    This report describes an investigation of the pathological mechanism of acute renal failure caused by toxic tubular necrosis after treatment with aristolochic acid I (AAI) in Sprague–Dawley (SD) rats. The rats were gavaged with AAI at 0, 5, 20, or 80 mg/kg/day for 7 days. The pathologic examination of the kidneys showed severe acute tubular degenerative changes primarily affecting the proximal tubules. Supporting these results, we detected significantly increased concentrations of blood urea nitrogen (BUN) and creatinine (Cr) in the rats treated with AAI, indicating damage to the kidneys. Ultrastructural examination showed that proximal tubular mitochondria were extremely enlarged and dysmorphic with loss and disorientation of their cristae. Mitochondrial function analysis revealed that the two indicators for mitochondrial energy metabolism, the respiratory control ratio (RCR) and ATP content, were reduced in a dose-dependent manner after AAI treatment. The RCR in the presence of substrates for complex I was reduced more significantly than in the presence of substrates for complex II. In additional experiments, the activity of respiratory complex I, which is partly encoded by mitochondrial DNA (mtDNA), was more significantly impaired than that of respiratory complex II, which is completely encoded by nuclear DNA (nDNA). A real-time PCR assay revealed a marked reduction of mtDNA in the kidneys treated with AAI. Taken together, these results suggested that mtDNA depletion and respiratory chain defects play critical roles in the pathogenesis of kidney injury induced by AAI, and that the same processes might contribute to aristolochic acid-induced nephrotoxicity in humans. -- Highlights: ► AAI-induced acute renal failure in rats and the proximal tubule was the target. ► Tubular mitochondria were morphologically aberrant in ultrastructural examination. ► AAI impair mitochondrial bioenergetic function and mtDNA replication.

  17. Enhancing the strategic management of practice learning through the introduction of the role of Learning Environment Manager.

    Science.gov (United States)

    Congdon, Graham; Baker, Tracey; Cheesman, Amanda

    2013-03-01

    This paper describes a process evaluation project designed to enhance the strategic management of practice learning within a large Hospital in the North of England. The aim of the project was to introduce the role of the Learning Environment Manager with dedicated responsibility for practice learning of undergraduate student nurses within the Hospital's 49 practice-settings. Whilst aspects of this role were already evident in several of these settings, the project sought to locate and standardise responsibilities related to the organisation and management of learning and teaching in practice explicitly within the existing staffing structure of each practice-setting. Focus group interviews were used to explore significant aspects of the project with key stakeholder groups comprising Learning Environment Managers, the Hospital Clinical Educator, Hospital Department Managers, Ward Managers, Mentors, University Link Lecturers and undergraduate Student Nurses. Interview data were analysed using thematic content analysis. The findings of the project suggest that the Learning Environment Manager role affords providers of practice learning with a robust approach to establish organisation-wide benchmarks that standardise the strategic management of practice learning in collaboration with partner Universities. The role incorporated many operational activities previously undertaken by the Hospital Clinical Educator, thus enabling the Hospital Clinical Educator to make a more strategic contribution to the on-going quality monitoring and enhancement of practice learning across the Hospital. The Learning Environment Manager role was found to provide mentors with high levels of support which in turn helped to promote consistent, positive and holistic practice learning experiences for undergraduate student nurses across the Hospital. Importantly, the role offers a potent catalyst for nurses in practice to regain responsibility for practice learning and re-establish the value of

  18. Learning through role-playing games: an approach for active learning and teaching

    Directory of Open Access Journals (Sweden)

    Marco Antonio Ferreira Randi

    Full Text Available This study evaluates the use of role-playing games (RPGs as a methodological approach for teaching cellular biology, assessing student satisfaction, learning outcomes, and retention of acquired knowledge. First-year undergraduate medical students at two Brazilian public universities attended either an RPG-based class (RPG group or a lecture (lecture-based group on topics related to cellular biology. Pre- and post-RPG-based class questionnaires were compared to scores in regular exams and in an unannounced test one year later to assess students' attitudes and learning. From the 230 students that attended the RPG classes, 78.4% responded that the RPG-based classes were an effective tool for learning; 55.4% thought that such classes were better than lectures but did not replace them; and 81% responded that they would use this method. The lecture-based group achieved a higher grade in 1 of 14 regular exam questions. In the medium-term evaluation (one year later, the RPG group scored higher in 2 of 12 questions. RPG classes are thus quantitatively as effective as formal lectures, are well accepted by students, and may serve as educational tools, giving students the chance to learn actively and potentially retain the acquired knowledge more efficiently.

  19. What Role do Metaphors Play in Game-based Learning Processes?

    DEFF Research Database (Denmark)

    Henriksen, Thomas Duus

    2015-01-01

    This chapter explores the role played by metaphors in learning games and game-based learning processes. The aim is to contribute better understanding of the mechanisms of how such games contribute to learning and learning transfer. On the basis of an analytical strategy that emphasises metaphors...... as storylines, actors, acts and movement, three learning games are analysed in order to understand how learningemerges in association to game-embedded metaphors.As shown in this chapter, metaphorsseem to play a profound role in game-based learning, both by providing participantswith a suitcase containing...

  20. Self-Regulated Learning: The Role of Motivation, Emotion, and Use of Learning Strategies in Students' Learning Experiences in a Self-Paced Online Mathematics Course

    Science.gov (United States)

    Cho, Moon-Heum; Heron, Michele L.

    2015-01-01

    Enrollment in online remedial mathematics courses has increased in popularity in institutions of higher learning; however, students unskilled in self-regulated learning (SRL) find online remedial mathematics courses particularly challenging. We investigated the role of SRL, specifically motivation, emotion, and learning strategies, in students'…

  1. Role of Symbolic Coding and Rehearsal Processes in Observational Learning

    Science.gov (United States)

    Bandura, Albert; Jeffery, Robert W.

    1973-01-01

    Results were interpreted supporting a social learning view of observational learning that emphasizes contral processing of response information in the acquisition phase and motor reproduction and incentive processes in the overt enactment of what has been learned. (Author)

  2. Gesture's role in speaking, learning, and creating language.

    Science.gov (United States)

    Goldin-Meadow, Susan; Alibali, Martha Wagner

    2013-01-01

    When speakers talk, they gesture. The goal of this review is to investigate the contribution that these gestures make to how we communicate and think. Gesture can play a role in communication and thought at many timespans. We explore, in turn, gesture's contribution to how language is produced and understood in the moment; its contribution to how we learn language and other cognitive skills; and its contribution to how language is created over generations, over childhood, and on the spot. We find that the gestures speakers produce when they talk are integral to communication and can be harnessed in a number of ways. (a) Gesture reflects speakers' thoughts, often their unspoken thoughts, and thus can serve as a window onto cognition. Encouraging speakers to gesture can thus provide another route for teachers, clinicians, interviewers, etc., to better understand their communication partners. (b) Gesture can change speakers' thoughts. Encouraging gesture thus has the potential to change how students, patients, witnesses, etc., think about a problem and, as a result, alter the course of learning, therapy, or an interchange. (c) Gesture provides building blocks that can be used to construct a language. By watching how children and adults who do not already have a language put those blocks together, we can observe the process of language creation. Our hands are with us at all times and thus provide researchers and learners with an ever-present tool for understanding how we talk and think.

  3. Defect modelling

    International Nuclear Information System (INIS)

    Norgett, M.J.

    1980-01-01

    Calculations, drawing principally on developments at AERE Harwell, of the relaxation about lattice defects are reviewed with emphasis on the techniques required for such calculations. The principles of defect modelling are outlined and various programs developed for defect simulations are discussed. Particular calculations for metals, ionic crystals and oxides, are considered. (UK)

  4. The Role of Identity and Power in Organizational Learning

    DEFF Research Database (Denmark)

    Jørgensen, Kenneth Mølbjerg; Keller, Hanne Dauer

    2005-01-01

    learning processes in organizations. It follows that organizations have to give up the illusion that it can control learning processes in a narrow goal-oriented sense. Instead organizational learning has to must be nurtured from different agendas, motives, and intentions, which push learning in different...

  5. An investigation of the role of defect levels on the radiation response of synthetic diamond crystals when used as sensors for the detection of mammography X-rays.

    Science.gov (United States)

    Ade, Nicholas

    2017-09-01

    This study evaluates the role of defects on the performances of synthetic diamond sensors on exposure to mammography X-rays. Through systematic investigations, the main cause of instability of response of examined sensors necessitating pre-irradiation was isolated and ascribed to the presence of ambient light which has the effect of emptying shallow trapping levels. The changes in response between measurements in light and dark conditions varied from 2.8 ± 1.2% to 63.0 ± 0.3%. Sensitivities between 0.4 and 6.7nCGy -1 mm -3 determined for the sensors varied with defect levels. The study indicates that differences in crystal quality due to the presence and influence of defects would cause a discrepancy in the dosimetric performances of various diamond detectors. Once a sensor plate is selected (based on the influence of defect levels) and coupled to the probe housing with the response of the diamond sensor stabilised and appropriately shielded from ambient light, daily priming is not needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. The Role of Hydrogen-Enhanced Strain-Induced Lattice Defects on Hydrogen Embrittlement Susceptibility of X80 Pipeline Steel

    Science.gov (United States)

    Hattori, M.; Suzuki, H.; Seko, Y.; Takai, K.

    2017-08-01

    Studies to date have not completely determined the factors influencing hydrogen embrittlement of ferrite/bainite X80 pipeline steel. Hydrogen embrittlement susceptibility was evaluated based on fracture strain in tensile testing. We conducted a thermal desorption analysis to measure the amount of tracer hydrogen corresponding to that of lattice defects. Hydrogen embrittlement susceptibility and the amount of tracer hydrogen significantly increased with decreasing crosshead speed. Additionally, a significant increase in the formation of hydrogen-enhanced strain-induced lattice defects was observed immediately before the final fracture. In contrast to hydrogen-free specimens, the fracture surface of the hydrogen-charged specimens exhibited shallower dimples without nuclei, such as secondary phase particles. These findings indicate that the presence of hydrogen enhanced the formation of lattice defects, particularly just prior to the occurrence of final fracture. This in turn enhanced the formation of shallower dimples, thereby potentially causing premature fracture of X80 pipeline steel at lower crosshead speeds.

  7. Quasiparticle Scattering in the Rashba Semiconductor BiTeBr: The Roles of Spin and Defect Lattice Site.

    Science.gov (United States)

    Butler, Christopher John; Yang, Po-Ya; Sankar, Raman; Lien, Yen-Neng; Lu, Chun-I; Chang, Luo-Yueh; Chen, Chia-Hao; Wei, Ching-Ming; Chou, Fang-Cheng; Lin, Minn-Tsong

    2016-09-28

    Observations of quasiparticle interference have been used in recent years to examine exotic carrier behavior at the surfaces of emergent materials, connecting carrier dispersion and scattering dynamics to real-space features with atomic resolution. We observe quasiparticle interference in the strongly Rashba split 2DEG-like surface band found at the tellurium termination of BiTeBr and examine two mechanisms governing quasiparticle scattering: We confirm the suppression of spin-flip scattering by comparing measured quasiparticle interference with a spin-dependent elastic scattering model applied to the calculated spectral function. We also use atomically resolved STM maps to identify point defect lattice sites and spectro-microscopy imaging to discern their varying scattering strengths, which we understand in terms of the calculated orbital characteristics of the surface band. Defects on the Bi sublattice cause the strongest scattering of the predominantly Bi 6p derived surface band, with other defects causing nearly no scattering near the conduction band minimum.

  8. Role of interfacial defect creation-annihilation processes at grain boundaries on the diffusional creep of polycrystalline alumina

    International Nuclear Information System (INIS)

    Ikuma, Y.; Gordon, R.S.

    1981-01-01

    It is generally assumed in the diffusional creep of a polycrystalline solid that grain boundaries act as perfect sources and sinks for lattice defects. However, if this assumption is not valid, then diffusional creep can become rate limited by interfacial defect reactions at grain boundaries. Steady state diffusional creep data will be presented at 1450 to 1500 0 C for polycrystalline alumina doped with Ti and a Mg-Ti co-dopant, which are consistent with interfacial controlled kinetics over an intermediate grain size range. A new type of creep deformation map will be presented which reveals the range of grain sizes and impurity concentrations over which interfacial defect creation and/or annihilation processes are important in the steady state creep of polycrystalline alumina

  9. Learning Cultures in Small to Medium-Size Enterprises and Their Role in Supporting the Learning Region

    Science.gov (United States)

    Fitzpatrick, Maeve; O'Connell, Janice; Murphy, Eamonn

    2010-01-01

    The role of work-based learning is a pivotal part of developing the learning region. With rates of employment at their highest for many years across Europe, the need for up-skilling the workforce in many areas will be essential to retain competitiveness and employability. This paper will focus on quality management up-skilling in small to…

  10. The Strategic Role of Digital Libraries: Issues in E-Learning Environments.

    Science.gov (United States)

    Wang, Mei-Yu

    2003-01-01

    Describes research aimed at providing educational organizations with practical strategies for implementing electronic learning (e-learning), based on focus group discussions at an elementary school in Taiwan. Considers the strategic role of digital libraries in electronic learning environments, library collections, digital technology, human…

  11. The role of professional objects in technology-enhanced learning environments in higher education

    NARCIS (Netherlands)

    Zitter, I.I.; Bruijn, E. de; Simons, P.R.J.; Cate, Th.J. ten

    2010-01-01

    We study project-based, technology-enhanced learning environments in higher education, which should produce, by means of specific mechanisms, learning outcomes in terms of transferable knowledge and learning-, thinking-, collaboration- and regulation-skills. Our focus is on the role of objects from

  12. Experimental Investigation of the Role of Defects in Detonation Sensitivity of Energetic Materials: Development of Techniques for Characterization

    Science.gov (United States)

    2009-12-31

    materials. The initial work was focused on design and construction of an apparatus for injecting defects into the crystals using PZT ceramics ...in the energy partitioning (Table 2), which offers some insight into the nature of the energetic texture of crystalline materials not apparent in

  13. O vacancy formation in (Pr/Gd)BaCo2O5.5 and the role of antisite defects

    KAUST Repository

    Omotayo Akande, Salawu; Chroneos, Alexander; Schwingenschlö gl, Udo

    2017-01-01

    that O vacancy formation is significantly easier in PrBaCo2O5.5 than in GdBaCo2O5.5, the difference in formation energy being hardly modified by antisite defects. While pyramidally coordinated Co atoms are not affected, we show that the presence

  14. Thermo-enhanced field emission from ZnO nanowires: Role of defects and application in a diode flat panel X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhipeng; Chen, Daokun; Chen, Wenqing; Chen, Yicong; Song, Xiaomeng; Zhan, Runze; Deng, Shaozhi; Xu, Ningsheng; Chen, Jun, E-mail: stscjun@mail.sysu.edu.cn

    2017-03-31

    Highlights: • A thermo-enhanced field emission phenomenon was observed from dendritic ZnO nanowires under the temperature of 323–723 K. • Defect-assisted field emission mechanism was proposed and quantitative calculation fits well with the experiment results. • The mechanism was verified by the field emission from ZnO nanowires with different defect concentrations. • A diode X-ray source making use of thermo-enhanced field emission phenomenon was proposed for separate tuning of dose and energy. - Abstract: A thermo-enhanced field emission phenomenon was observed from ZnO nanowires. The field emission current increased by almost two orders of magnitude under a constant applied electric field, and the turn-on field decreased from 6.04 MV/m to 5.0 MV/m when the temperature increased from 323 to 723 K. The Poole–Frenkel electron excitation from the defect-induced trapping centers to the conduction band under high electric fields is believed to be the primary cause of the observed phenomenon. The experimental results fit well with the proposed physical model. The field emission from ZnO nanowires with different defect concentrations further confirmed the role of defects. Using the thermo-enhanced field emission phenomenon, a diode flat panel X-ray source was demonstrated, for which the energy and dose can be separately tuned. The thermo-enhanced field emission phenomenon observed from ZnO nanowires could be an effective way to realize a large area flat panel multi-energy X-ray source.

  15. Roles for Drosophila Mushroom Body Neurons in Olfactory Learning and Memory

    Science.gov (United States)

    Zong, Lin; Tanaka, Nobuaki K.; Ito, Kei; Davis, Ronald L.; Akalal, David-Benjamin G.; Wilson, Curtis F.

    2006-01-01

    Olfactory learning assays in Drosophila have revealed that distinct brain structures known as mushroom bodies (MBs) are critical for the associative learning and memory of olfactory stimuli. However, the precise roles of the different neurons comprising the MBs are still under debate. The confusion surrounding the roles of the different neurons…

  16. Preliminary Study on the Role of Social Presence in Blended Learning Environment in Higher Education

    Science.gov (United States)

    Jusoff, Kamaruzaman; Khodabandelou, Rouhollah

    2009-01-01

    This paper contributes to the growing body of knowledge which identifies benefits for Blended Learning in the understanding of social processes role. It reports on an exploratory study into the role of social presence in blended learning environment. Employing a qualitative methodology, the study sought to understand social presence of learners in…

  17. Exploring the Roles of Parents and Students in EFL Literacy Learning: A Colombian Case

    Science.gov (United States)

    Hurtado Torres, Sergio Aldemar; Castañeda-Peña, Harold Andrés

    2016-01-01

    There is little scholarly information about parent involvement in their children's English as a Foreign Language (EFL henceforth) literacy learning in the Colombian context. This exploratory-qualitative study looks into the possible roles of parents and children in EFL literacy learning at home, with special emphasis on parental roles and…

  18. The Impact of Role Modeling on Proteges' Personal Learning and Work-to-Family Enrichment

    Science.gov (United States)

    Kwan, Ho Kwong; Mao, Yina; Zhang, Haina

    2010-01-01

    The present study investigates the impact of role modeling as perceived by proteges on their personal learning (i.e., relational job learning and personal skill development) and work-to-family enrichment (WFE). Results from a two-wave field survey of 173 proteges in the People's Republic of China indicate that role modeling positively affects…

  19. Defects in dilute nitrides

    International Nuclear Information System (INIS)

    Chen, W.M.; Buyanova, I.A.; Tu, C.W.; Yonezu, H.

    2005-01-01

    We provide a brief review our recent results from optically detected magnetic resonance studies of grown-in non-radiative defects in dilute nitrides, i.e. Ga(In)NAs and Ga(Al,In)NP. Defect complexes involving intrinsic defects such as As Ga antisites and Ga i self interstitials were positively identified.Effects of growth conditions, chemical compositions and post-growth treatments on formation of the defects are closely examined. These grown-in defects are shown to play an important role in non-radiative carrier recombination and thus in degrading optical quality of the alloys, harmful to performance of potential optoelectronic and photonic devices based on these dilute nitrides. (author)

  20. Wiring Role Taking in Collaborative Learning Environments. SNA and Semantic Web can improve CSCL script?

    Directory of Open Access Journals (Sweden)

    Nicola Capuano

    2014-04-01

    Full Text Available Over the past years the concept of role in distance education has become a promising construct for analysing and facilitating collaborative processes and outcomes. Designing effective collaborative learning processes is a complex task that can be supported by existing good practices formulated as pedagogical patterns or scripts. Over the past years, the research on technology enhanced learning has shown that collaborative scripts for learning act as mediating artefacts not only designing educational scenarios but also structuring and prescribing roles and activities. Conversely, existing learning systems are not able to provide dynamic role management in the definition and execution of collaborative scripts. This work proposes the application of Social Network Analysis in order to evaluate the expertise level of a learner when he/she is acting, with an assigned role, within the execution of a collaborative script. Semantic extensions to both IMS Learning Design and Information Packaging specifications are also proposed to support roles management.

  1. A hypothesis on a role of oxytocin in the social mechanisms of speech and vocal learning.

    Science.gov (United States)

    Theofanopoulou, Constantina; Boeckx, Cedric; Jarvis, Erich D

    2017-08-30

    Language acquisition in humans and song learning in songbirds naturally happen as a social learning experience, providing an excellent opportunity to reveal social motivation and reward mechanisms that boost sensorimotor learning. Our knowledge about the molecules and circuits that control these social mechanisms for vocal learning and language is limited. Here we propose a hypothesis of a role for oxytocin (OT) in the social motivation and evolution of vocal learning and language. Building upon existing evidence, we suggest specific neural pathways and mechanisms through which OT might modulate vocal learning circuits in specific developmental stages. © 2017 The Authors.

  2. A Study on the Role of Drama in Learning Mathematics

    OpenAIRE

    Elahe Masoum; Mohsen Rostamy-Malkhalifeh; Zahra Kalantarnia

    2013-01-01

    Present educational systems needs modern strategies for teaching and learning. Mathematics education has to change for students in elementary schools. One of the modern strategies, it is drama activities. The drama is as empirical aspect of learning. The student may learn from what they are doing in drama. They are so active instead having a passive shape in drama, in fact, students are learning, finding experiences and new paths from drama as well. The students could find its capabilities, r...

  3. Using PLEs in Professional Learning Scenarios - The Festo Case for ROLE

    OpenAIRE

    Scheffel, Maren; Schmidt,, Manuel; Werkle, Michael; Wolpers, Martin

    2013-01-01

    The competitiveness of a company depends strongly on the skills and abilities of its employees. Teachers and learners within companies often lack media competence and the ability to use self-regulated learning (SRL). The evaluations conducted in the scope of the Responsive Open Learning Environment (ROLE) project showed that the vocational training and workplace learning providers appreciated the SRL approach and the idea of personalisation of the learning tools and content. Further, the impl...

  4. Role of Class III phosphoinositide 3-kinase in the brain development: possible involvement in specific learning disorders.

    Science.gov (United States)

    Inaguma, Yutaka; Matsumoto, Ayumi; Noda, Mariko; Tabata, Hidenori; Maeda, Akihiko; Goto, Masahide; Usui, Daisuke; Jimbo, Eriko F; Kikkawa, Kiyoshi; Ohtsuki, Mamitaro; Momoi, Mariko Y; Osaka, Hitoshi; Yamagata, Takanori; Nagata, Koh-Ichi

    2016-10-01

    Class III phosphoinositide 3-kinase (PIK3C3 or mammalian vacuolar protein sorting 34 homolog, Vps34) regulates vesicular trafficking, autophagy, and nutrient sensing. Recently, we reported that PIK3C3 is expressed in mouse cerebral cortex throughout the developmental process, especially at early embryonic stage. We thus examined the role of PIK3C3 in the development of the mouse cerebral cortex. Acute silencing of PIK3C3 with in utero electroporation method caused positional defects of excitatory neurons during corticogenesis. Time-lapse imaging revealed that the abnormal positioning was at least partially because of the reduced migration velocity. When PIK3C3 was silenced in cortical neurons in one hemisphere, axon extension to the contralateral hemisphere was also delayed. These aberrant phenotypes were rescued by RNAi-resistant PIK3C3. Notably, knockdown of PIK3C3 did not affect the cell cycle of neuronal progenitors and stem cells at the ventricular zone. Taken together, PIK3C3 was thought to play a crucial role in corticogenesis through the regulation of excitatory neuron migration and axon extension. Meanwhile, when we performed comparative genomic hybridization on a patient with specific learning disorders, a 107 Kb-deletion was identified on 18q12.3 (nt. 39554147-39661206) that encompasses exons 5-23 of PIK3C3. Notably, the above aberrant migration and axon growth phenotypes were not rescued by the disease-related truncation mutant (172 amino acids) lacking the C-terminal kinase domain. Thus, functional defects of PIK3C3 might impair corticogenesis and relate to the pathophysiology of specific learning disorders and other neurodevelopmental disorders. Acute knockdown of Class III phosphoinositide 3-kinase (PIK3C3) evokes migration defects of excitatory neurons during corticogenesis. PIK3C3-knockdown also disrupts axon outgrowth, but not progenitor proliferation in vivo. Involvement of PIK3C3 in neurodevelopmental disorders might be an interesting future

  5. The Role of Peripherality in Students' Entrepreneurial Learning

    Science.gov (United States)

    Kubberød, Elin; Pettersen, Inger Beate

    2018-01-01

    Purpose: The purpose of this paper is to expand on the entrepreneurial learning literature and situated learning theory to explore how students with different educational backgrounds learn to recognise opportunities at the periphery of an entrepreneurial practice. The authors theoretically outline factors that may influence students'…

  6. Social Learning by Design: The Role of Social Media

    Science.gov (United States)

    Brooks, Laura

    2009-01-01

    It is no secret that learning has a social context. As library media specialists work with students nearly every day, they take for granted their pedagogical roots in social learning theory based on the premise that students need modeling and observation to learn from one another. Information gathering becomes a key activity, and social…

  7. Emotions and Multimedia Learning: The Moderating Role of Learner Characteristics

    Science.gov (United States)

    Knörzer, L.; Brünken, R.; Park, B.

    2016-01-01

    The Cognitive-Affective Theory of Learning with Media postulates that affective factors as well as individual learner characteristics impact multimedia learning. The present study investigated how experimentally induced positive and negative emotions influence multimedia learning and how learner characteristics moderated this impact. Results…

  8. THE BIGGS AND MOORE MODEL IN E-LEARNING: The Role of Motivation and Collaboration as Moderators

    OpenAIRE

    Matti J. HAVERILA

    2012-01-01

    The purpose of this paper is to report the findings of a research conducted to evaluate the effect of e-learning experience on students’ perceived learning outcomes, and more specifically the role of motivation and collaboration as moderators between the e-learning experience and the learning outcome. The perceived learning outcome was measured with whether the students perceived to learn more in e-learning vis-à-vis traditional learning context. The participants came from an undergraduat...

  9. The nursing educator's role in e-learning: a literature review.

    Science.gov (United States)

    Koch, Lee F

    2014-11-01

    e-Learning is becoming more commonplace in nursing and healthcare professional education. Research has shown that e-learning can be just as effective at helping students achieve cognitive learning objectives as traditional face-to-face courses, provided that certain quality criteria are met. However, the decentralized, asynchronous nature of e-learning precludes spontaneous, personal interaction between the instructor and the learner. In addition to this, learning objectives in nursing and other healthcare professions are not only within the cognitive, but also within the affective and psychomotor domains. This article seeks to answer the following question: How does e-learning transform the role of nurse educators? Narrative literature review. A comprehensive database search was conducted using the English and German key words "teacher," "educator," "role," "e-learning," and "nursing" to identify literature that examined the role of (nurse) educators in e-learning. The search strategy resulted in the inclusion of 40 sources. The majority of the literature is expert opinion and examines the educator's role in e-learning from a theoretical point of view (n=30). There is a paucity of empirical research pertaining directly to the educator's role (n=10). Only four sources deal specifically with the nurse educator's role. The literature agrees on the need for a new role definition in light of e-learning. This role is more complex than the educator's traditional role. The literature does not provide any indication of how the educator's role can be adapted to the specific needs of online nurse education. There is a need for more empirical research on this subject. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. The Role of BDNF in the Development of Fear Learning.

    Science.gov (United States)

    Dincheva, Iva; Lynch, Niccola B; Lee, Francis S

    2016-10-01

    Brain-derived neurotrophic factor (BDNF) is a growth factor that is dynamically expressed in the brain across postnatal development, regulating neuronal differentiation and synaptic plasticity. The neurotrophic hypothesis of psychiatric mood disorders postulates that in the adult brain, decreased BDNF levels leads to altered neural plasticity, contributing to disease. Although BDNF has been established as a key factor regulating the critical period plasticity in the developing visual system, it has recently been shown to also play a role in fear circuitry maturation, which has implications for the emergence of fear-related mood disorders. This review provides a detailed overview of developmental changes in expression of BDNF isoforms, as well as their receptors across postnatal life. In addition, recent developmental studies utilizing a genetic BDNF single nucleotide polymorphism (Val66Met) knock-in mouse highlight the impact of BDNF on fear learning during a sensitive period spanning the transition into adolescent time frame. We hypothesize that BDNF in the developing brain regulates fear circuit plasticity during a sensitive period in early adolescence, and alterations in BDNF expression (genetic or environmental) have a persistent impact on fear behavior and fear-related disorders. © 2016 Wiley Periodicals, Inc.

  11. A simple role for BDNF in learning and memory?

    Directory of Open Access Journals (Sweden)

    Carla Cunha

    2010-02-01

    Full Text Available Since its discovery almost three decades ago, the secreted neurotrophin brain-derived neurotrophic factor (BDNF has been firmly implicated in the differentiation and survival of neurons of the CNS. More recently, BDNF has also emerged as an important regulator of synaptogenesis and synaptic plasticity mechanisms underlying learning and memory in the adult CNS. In this review we will discuss our knowledge about the multiple intracellular signalling pathways activated by BDNF, and the role of this neurotrophin in long-term synaptic plasticity and memory formation as well as in synaptogenesis. We will show that maturation of BDNF, its cellular localisation and its ability to regulate both excitatory and inhibitory synapses in the CNS may result in conflicting alterations in synaptic plasticity and memory formation. Lack of a precise knowledge about the mechanisms by which BDNF influences higher cognitive functions and complex behaviours may constitute a severe limitation in the possibility to devise BDNF-based therapeutics for human disorders of the CNS.

  12. Role of defects in tuning the electronic properties of monolayer WS{sub 2} grown by chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jie; Zheliuk, Oleksandr; Lu, Jianming; Ye, Jianting [Zernike Institute for Advanced Materials, University of Groningen, Groningen (Netherlands); Gordiichuk, Pavlo [Zernike Institute for Advanced Materials, University of Groningen, Groningen (Netherlands); Department of Chemistry, Northwestern University, Evanston, IL (United States); Herrmann, Andreas [Zernike Institute for Advanced Materials, University of Groningen, Groningen (Netherlands); Molecular Biophysics, Department of Biology, Humboldt-Universitaet Berlin (Germany)

    2017-10-15

    Two-dimensional transition metal dichalcogenides have already attracted enormous research interest. To understand the dependence of electronic properties on the quality and defect morphology is vital for synthesizing high quality materials and the realization of functional devices. Here, we demonstrate the mapping of the conductive variations by conducting atomic force microscopy (C-AFM) in the monolayer tungsten disulfide (WS{sub 2}) grown by chemical vapor deposition. The electronic properties are strongly affected by the formation of vacancies in monolayer WS{sub 2} during growth, which is also verified by the photoluminescence. This spatial study of defects provides opportunities for optimization of the growth process for enhancing devices performance of TMDs monolayers. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Supervisor's role in training programs as a manager of learning program

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available According to the training literature, a supervisor's role in training programs has two major elements: supervisor support and supervisor communication. The ability of supervisors to play effective roles in training programs may increase employees' motivation to learn. The nature of this relationship is interesting, but the role of supervisor's role as a predicting variable is less emphasized in a training program models. Therefore, this study was conducted to examine the effect of supervisor's role in training programs on motivation to learn using 152 usable questionnaires gathered from non-academic employees who have worked in a technological based public university, Malaysia. The outcomes of stepwise regression analysis showed that the supervisor support and supervisor communication significantly associated with motivation to learn. Statistically, this result demonstrates that supervisor's role in training programs does act as an important predictor of motivation to learn in the organizational sample. In addition, discussion, implication and conclusion are elaborated.

  14. The Impact of Post-Synthetic Linker Functionalization of MOFs on Methane Storage: The Role of Defects

    Energy Technology Data Exchange (ETDEWEB)

    Szilágyi, Petra Ágota, E-mail: p.a.szilagyi@greenwich.ac.uk [Department of Pharmaceutical, Chemical and Environmental Sciences, University of Greenwich, Chatham (United Kingdom); Serra-Crespo, Pablo [Department of Radiation Science and Technology, Delft University of Technology, Delft (Netherlands); Gascon, Jorge [Department of Chemical Engineering, Delft University of Technology, Delft (Netherlands); Geerlings, Hans [Department of Chemical Engineering, Delft University of Technology, Delft (Netherlands); Shell Technology Centre, Amsterdam (Netherlands); Dam, Bernard [Department of Chemical Engineering, Delft University of Technology, Delft (Netherlands)

    2016-03-29

    Natural gas is increasingly being viewed as one of the most viable alternatives to gasoline. However, its vehicular application will only be widespread if safe and high-capacity methane stores are developed. In this work, we report an over 33% increase in methane uptake on a post-synthetically modified metal–organic framework. The underlying mechanism for this dramatic increase is due to lattice defects formed upon post-synthetic modification. This method may open new approaches to natural gas storage.

  15. The Impact of Post-Synthetic Linker Functionalization of MOFs on Methane Storage: The Role of Defects

    International Nuclear Information System (INIS)

    Szilágyi, Petra Ágota; Serra-Crespo, Pablo; Gascon, Jorge; Geerlings, Hans; Dam, Bernard

    2016-01-01

    Natural gas is increasingly being viewed as one of the most viable alternatives to gasoline. However, its vehicular application will only be widespread if safe and high-capacity methane stores are developed. In this work, we report an over 33% increase in methane uptake on a post-synthetically modified metal–organic framework. The underlying mechanism for this dramatic increase is due to lattice defects formed upon post-synthetic modification. This method may open new approaches to natural gas storage.

  16. O vacancy formation in (Pr/Gd)BaCo2O5.5 and the role of antisite defects

    KAUST Repository

    Omotayo Akande, Salawu

    2017-04-20

    In search for materials for intermediate temperature solid oxide fuel cells, (Pr/Gd)BaCo2O5.5 is investigated by first principles calculations. Antisite defects are considered as they may modify the electronic and O diffusion properties but are rarely studied in double perovskite oxides. Octahedrally coordinated Co atoms are shown to realize intermediate and high spin states for PrBaCo2O5.5 and GdBaCo2O5.5, respectively, while pyramidally coordinated Co atoms always have high spin. It turns out that O vacancy formation is significantly easier in PrBaCo2O5.5 than in GdBaCo2O5.5, the difference in formation energy being hardly modified by antisite defects. While pyramidally coordinated Co atoms are not affected, we show that the presence of antisite defects causes parts of the octahedrally coordinated Co atoms to switch from intermediate to high spin.

  17. Role of implicit learning abilities in metaphor understanding.

    Science.gov (United States)

    Drouillet, Luc; Stefaniak, Nicolas; Declercq, Christelle; Obert, Alexandre

    2018-05-01

    Although the use of metaphors is a central component of language, the processes that sustain their comprehension have yet to be specified. Work in the fields of both metaphors and implicit learning suggests that implicit learning abilities facilitate the comprehension of metaphors. However, to date, no study has directly explored the relationships between the understanding of metaphors and so-called implicit learning tasks. We used a meaning decision task comparing literal, metaphorical and meaningless expressions to assess metaphor understanding and a probabilistic serial reaction time task for assessing implicit learning. Our results show that implicit learning positively predicts the time gap between responses to literal and metaphorical expressions and negatively predicts the difference between metaphorical and meaningless expressions. Thus, when confronted with novel metaphors, participants with higher implicit learning abilities are better able to identify that the expressions have some meaning. These results are interpreted in the context of metaphor understanding and psycholinguistic theories. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. You Like It, You Learn It: Affectivity and Learning in Competitive Social Role Play Gaming

    Science.gov (United States)

    Brom, Cyril; Šisler, Vít; Slussareff, Michaela; Selmbacherová, Tereza; Hlávka, Zdenek

    2016-01-01

    Despite the alleged ability of digital game-based learning (DGBL) to foster positive affect and in turn improve learning, the link between affectivity and learning has not been sufficiently investigated in this field. Regarding learning from team-based games with competitive elements, even less is known about the relationship between…

  19. Organisational Learning as an Emerging Process: The Generative Role of Digital Tools in Informal Learning Practices

    Science.gov (United States)

    Za, Stefano; Spagnoletti, Paolo; North-Samardzic, Andrea

    2014-01-01

    Increasing attention is paid to organisational learning, with the success of contemporary organisations strongly contingent on their ability to learn and grow. Importantly, informal learning is argued to be even more significant than formal learning initiatives. Given the widespread use of digital technologies in the workplace, what requires…

  20. Exploring the Moderating Role of Self-Management of Learning in Mobile English Learning

    Science.gov (United States)

    Huang, Rui-Ting

    2014-01-01

    Although a considerable number of studies have revealed that self-management of learning (SML) could be closely related to learning achievements, there is still a paucity of research investigating the moderating effect of self-management of learning on mobile learning outcomes. Accordingly, the primary purpose of this study was to explore the…

  1. Renewed roles for librarians in problem-based learning in the medical curriculum.

    Science.gov (United States)

    Mi, Misa

    2011-01-01

    Problem-based learning (PBL) is a teaching-learning process or method of instruction that is widely used in medical education curricula. Librarians play important roles as facilitators for PBL as well as guides for information resources. Involvement in PBL activities presents unique opportunities to incorporate library resources and instruction into the medical curriculum. This article reviews the problem-based learning method within the conceptual framework of the learning theory of constructivism. It describes how a medical librarian at a U.S. medical school used emerging technologies to facilitate PBL small group case discussions, guide students to quality information resources, and enhance the learning environment for the PBL process.

  2. The Impact of Post-Synthetic Linker Functionalization of MOFs on Methane Storage: the Role of Defects

    Directory of Open Access Journals (Sweden)

    Petra Agota Szilagyi

    2016-03-01

    Full Text Available Natural gas is increasingly being viewed as one of the most viable alternatives to gasoline. Its vehicular application however will only be widespread if safe and high-capacity methane stores are developed. In this work report an over 33% increase in methane uptake on a post-synthetically modified metal-organic framework. The underlying mechanism for this dramatic increase is due to lattice defects formed upon post-synthetic modification. This method may open new approaches to natural gas storage.

  3. The Biggs and Moore Model in E-Learning: The Role of Motivation and Collaboration as Moderators

    Science.gov (United States)

    Haverila, Matti J.

    2012-01-01

    The purpose of this paper is to report the findings of a research conducted to evaluate the effect of e-learning experience on students' perceived learning outcomes, and more specifically the role of motivation and collaboration as moderators between the e-learning experience and the learning outcome. The perceived learning outcome was measured…

  4. Investigating the Role of Minecraft in Educational Learning Environments

    Science.gov (United States)

    Callaghan, Noelene

    2016-01-01

    This research paper identifies the way in which Minecraft Edu can be used to contribute to the teaching and learning of secondary students via a multiple case research study. Minecraft Edu is recognised as a gamification tool that enables its users to create and evaluate project-based learning activities within a classroom context. Learning…

  5. The Role of Interpretative Communities in Remembering and Learning

    Science.gov (United States)

    Shahzad, Farhat

    2011-01-01

    Students' memories and learning strategies are situated in their social relationships, political orientations, cultural meanings, worldviews, and historical experiences. This study uses qualitative research methods to investigate how Canadian students remember and learn about the War on Terror. It deals with the narratives of ninety-nine students…

  6. An active role for machine learning in drug development

    Science.gov (United States)

    Murphy, Robert F.

    2014-01-01

    Due to the complexity of biological systems, cutting-edge machine-learning methods will be critical for future drug development. In particular, machine-vision methods to extract detailed information from imaging assays and active-learning methods to guide experimentation will be required to overcome the dimensionality problem in drug development. PMID:21587249

  7. Mentoring: A Natural Role for Learning Community Faculty

    Science.gov (United States)

    Hessenauer, Sarah L.; Law, Kristi

    2017-01-01

    The purpose of this article is to highlight mentoring as an important piece of leading a learning community. The authors will share a definition of mentoring which is applicable to the learning community experience. Characteristics of mentoring will be described, including types of mentoring and mentor-mentee relationships. The authors will apply…

  8. The Role of Motivational Strategies in Self-Regulated Learning.

    Science.gov (United States)

    Garcia, Teresa

    1995-01-01

    A discussion of motivational techniques for promoting self-regulated learning in college students focuses on two methods students use to anticipate and negotiate the affective consequences of success and failure. The strategies, defensive pessimism and self-handicapping, are described and a study of their impact on self-regulated learning of 127…

  9. Learning Bridges: A Role for Mobile Technologies in Education

    Science.gov (United States)

    Vavoula, Giasemi; Sharples, Mike; Lonsdale, Peter; Rudman, Paul; Meek, Julia

    2007-01-01

    MyArtSpace is a service for children to spread their learning between schools and museums using mobile phones linked to a personal Web space. Using MyArtSpace as an example, the authors discuss the possibilities for mobile technology to form bridges between formal and informal learning. They also offer guidelines for designing such bridges.…

  10. The Roles of Protein Kinases in Learning and Memory

    Science.gov (United States)

    Giese, Karl Peter; Mizuno, Keiko

    2013-01-01

    In the adult mammalian brain, more than 250 protein kinases are expressed, but only a few of these kinases are currently known to enable learning and memory. Based on this information it appears that learning and memory-related kinases either impact on synaptic transmission by altering ion channel properties or ion channel density, or regulate…

  11. The role of networked learning in academics’ writing

    Directory of Open Access Journals (Sweden)

    Sharon McCulloch

    2017-11-01

    Full Text Available This article explores academics’ writing practices, focusing on the ways in which they use digital platforms in their processes of collaborative learning. It draws on interview data from a research project that has involved working closely with academics across different disciplines and institutions to explore their writing practices, understanding academic literacies as situated social practices. The article outlines the characteristics of academics’ ongoing professional learning, demonstrating the importance of collaborations on specific projects in generating learning in relation to using digital platforms and for sharing and collaborating on scholarly writing. A very wide range of digital platforms have been identified by these academics, enabling new kinds of collaboration across time and space on writing and research; but challenges around online learning are also identified, particularly the dangers of engaging in learning in public, the pressures of ‘always-on’-ness and the different values systems around publishing in different forums.

  12. Left-right asymmetry defect in the hippocampal circuitry impairs spatial learning and working memory in iv mice.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Goto

    Full Text Available Although left-right (L-R asymmetry is a fundamental feature of higher-order brain function, little is known about how asymmetry defects of the brain affect animal behavior. Previously, we identified structural and functional asymmetries in the circuitry of the mouse hippocampus resulting from the asymmetrical distribution of NMDA receptor GluR ε2 (NR2B subunits. We further examined the ε2 asymmetry in the inversus viscerum (iv mouse, which has randomized laterality of internal organs, and found that the iv mouse hippocampus exhibits right isomerism (bilateral right-sidedness in the synaptic distribution of the ε2 subunit, irrespective of the laterality of visceral organs. To investigate the effects of hippocampal laterality defects on higher-order brain functions, we examined the capacity of reference and working memories of iv mice using a dry maze and a delayed nonmatching-to-position (DNMTP task, respectively. The iv mice improved dry maze performance more slowly than control mice during acquisition, whereas the asymptotic level of performance was similar between the two groups. In the DNMTP task, the iv mice showed poorer accuracy than control mice as the retention interval became longer. These results suggest that the L-R asymmetry of hippocampal circuitry is critical for the acquisition of reference memory and the retention of working memory.

  13. Toward Intelligent Software Defect Detection

    Science.gov (United States)

    Benson, Markland J.

    2011-01-01

    Source code level software defect detection has gone from state of the art to a software engineering best practice. Automated code analysis tools streamline many of the aspects of formal code inspections but have the drawback of being difficult to construct and either prone to false positives or severely limited in the set of defects that can be detected. Machine learning technology provides the promise of learning software defects by example, easing construction of detectors and broadening the range of defects that can be found. Pinpointing software defects with the same level of granularity as prominent source code analysis tools distinguishes this research from past efforts, which focused on analyzing software engineering metrics data with granularity limited to that of a particular function rather than a line of code.

  14. The roles of testicular nuclear receptor 4 (TR4 in male fertility-priapism and sexual behavior defects in TR4 knockout mice

    Directory of Open Access Journals (Sweden)

    Bao Bo-Ying

    2011-10-01

    Full Text Available Abstract Background Successful reproductive efforts require the establishment of a situation favorable for reproduction that requires integration of both behavior and internal physiological events. TR4 nuclear receptor is known to be involved in male fertility via controlling spermatogenesis, yet its roles in regulating other biological events related to reproduction have not been completely revealed. Methods Male TR4 knockout (TR4-/- and wild type mice were used for the sexual behavior and penile dysfunction studies. Mice were sacrificed for histological examination and corresponding genes profiles were analyzed by quantitative RT-PCR. Reporter gene assays were performed. Results We describe an unexpected finding of priapism in TR4-/- mice. As a transcriptional factor, we demonstrated that TR4 transcriptionally modulates a key enzyme regulating penis erection and neuronal nitric oxide synthese NOS (nNOS. Thereby, elimination of TR4 results in nNOS reduction in both mRNA and protein levels, consequently may lead to erectile dysfunction. In addition, male TR4-/- mice display defects in sexual and social behavior, with increased fear or anxiety, as well as reduced mounting, intromission, and ejaculation. Reduction of ER alpha, ER beta, and oxytocin in the hypothalamus may contribute to defects in sexual behavior and stress response. Conclusions Together, these results provide in vivo evidence of important TR4 roles in penile physiology, as well as in male sexual behavior. In conjunction with previous finding, TR4 represents a key factor that controls male fertility via regulating behavior and internal physiological events.

  15. Tendon tissue engineering and its role on healing of the experimentally induced large tendon defect model in rabbits: a comprehensive in vivo study.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali

    2013-01-01

    Healing of large tendon defects is challenging. We studied the role of collagen implant with or without polydioxanone (PDS) sheath on the healing of a large Achilles tendon defect model, in rabbits. Sixty rabbits were divided into three groups. A 2 cm gap was created in the left Achilles tendon of all rabbits. In the control lesions, no implant was used. The other two groups were reconstructed by collagen and collagen-PDS implants respectively. The animals were clinically examined at weekly intervals and their lesions were observed by ultrasonography. Blood samples were obtained from the animals and were assessed for hematological analysis and determination of serum PDGF level, at 60 days post injury (DPI). The animals were then euthanized and their lesions were assessed for gross and histopathology, scanning electron microscopy, biomechanical testing, dry matter and hydroxyproline content. Another 65 pilot animals were also studied grossly and histopathologically to define the host implant interaction and graft incorporation at serial time points. The treated animals gained significantly better clinical scoring compared to the controls. Treatment with collagen and collagen-PDS implants significantly increased the biomechanical properties of the lesions compared to the control tendons at 60DPI (Ptendon. Implantation of the bioimplants had a significant role in initiating tendon healing and the implants were biocompatible, biodegradable and safe for application in tendon reconstructive surgery. The results of the present study may be valuable in clinical practice.

  16. Training and performance: The mediating role of organizational learning

    Directory of Open Access Journals (Sweden)

    María Isabel Barba Aragón

    2014-07-01

    Full Text Available Although there is a general recognition in the literature that training improves a firm's performance, empirical research does not always provide evidence to support this effect. One possible explanation is that training does not have a direct effect on performance but an indirect effect by improving other organizational outcomes. This paper suggests that organizational learning is one of those variables and that it mediates the relationship between training and performance and that the adoption of a learning-oriented training enhances performances through its positive effect on organizational learning. Using a sample of Spanish firms we obtain empirical evidence, which supports the view that this mediating effect is present.

  17. The role of leadership in facilitating Organisational Learning and collective capacity building

    OpenAIRE

    Piranfar, Hosein

    2007-01-01

    The paper examines the role of leadership in facilitating collective learning and capacity building by utilising ideas from the fields of evolutionary learning, operations strategy, quality, project and risk management. Two contrasting cases are chosen to show how success and failure can depend upon collective capacity building through participative leadership and Organisational Learning (OL). The bulk of the literature surveyed concerns evolutionary OL in particular those that involve leader...

  18. The roles of games in teaching and learning of mathematics in junior ...

    African Journals Online (AJOL)

    The roles of games in teaching and learning of mathematics in junior secondary schools. ... The research seeks to enhance the status of games in teaching mathematics in junior secondary schools curriculum ... AJOL African Journals Online.

  19. The role of CaMKII in cerebellar learning

    NARCIS (Netherlands)

    D.A. Andreev (Dmitri)

    2006-01-01

    textabstractThe molecular mechanisms underlying learning and memory are conserved between primitive and higher organized organisms. Memory formation requires plasticity between synaptic connections, and Ca2+ serves as an essential second messenger in the regulation of this plasticity.

  20. Electronic Human Resource Management: Organizational Responses to Role Conflicts Created by e-Learning

    Science.gov (United States)

    Oiry, Ewan

    2009-01-01

    Could enthusiasm for e-learning be dampened because it is detrimental to the relationships between those undergoing e-training and their direct managers or colleagues? Interviews conducted in four French banks provide material to explore this question. We see that e-learning has increasingly been adopted because it goes beyond the role limitations…

  1. The Role of the Basal Ganglia in Implicit Contextual Learning: A Study of Parkinson's Disease

    Science.gov (United States)

    van Asselen, Marieke; Almeida, Ines; Andre, Rui; Januario, Cristina; Goncalves, Antonio Freire; Castelo-Branco, Miguel

    2009-01-01

    Implicit contextual learning refers to the ability to memorize contextual information from our environment. This contextual information can then be used to guide our attention to a specific location. Although the medial temporal lobe is important for this type of learning, the basal ganglia might also be involved considering its role in many…

  2. The Role of L-type Calcium Channels in Olfactory Learning and Its Modulation by Norepinephrine

    Directory of Open Access Journals (Sweden)

    Abhinaba Ghosh

    2017-12-01

    Full Text Available L type calcium channels (LTCCs are prevalent in different systems and hold immense importance for maintaining/performing selective functions. In the nervous system, CaV1.2 and CaV1.3 are emerging as critical modulators of neuronal functions. Although the general role of these calcium channels in modulating synaptic plasticity and memory has been explored, their role in olfactory learning is not well understood. In this review article we first discuss the role of LTCCs in olfactory learning especially focusing on early odor preference learning in neonate rodents, presenting evidence that while NMDARs initiate stimulus-specific learning, LTCCs promote protein-synthesis dependent long-term memory (LTM. Norepinephrine (NE release from the locus coeruleus (LC is essential for early olfactory learning, thus noradrenergic modulation of LTCC function and its implication in olfactory learning is discussed here. We then address the differential roles of LTCCs in adult learning and learning in aged animals.

  3. The roles of electronic books in the transformation of learning and instruction

    NARCIS (Netherlands)

    Huang, Ronghuai; Chen, Nian-Shing; Kang, Myunghee; McKenney, Susan; Churchill, Daniel

    2014-01-01

    Huang, R., Chen, N., Kang, M. McKenney, S. & Churchill, D. (2013). The roles of electronic books in the transformation of learning and instruction. In N. Chen, R. Huang, Kinshuk, Y. Li, D. G. Sampson (Eds.) Proceedings of the IEEE 13th International Conference on Advanced Learning Technologies

  4. The Role of Leadership in Facilitating Organisational Learning and Collective Capacity Building

    Science.gov (United States)

    Piranfar, Hosein

    2007-01-01

    The paper examines the role of leadership in facilitating collective learning and capacity building by utilising ideas from the fields of evolutionary learning, operations strategy, quality, project and risk management. Two contrasting cases are chosen to show how success and failure can depend upon collective capacity building through…

  5. Roles and Characteristics of Television and Some Implications for Distance Learning.

    Science.gov (United States)

    Bates, Tony W.

    1982-01-01

    Explores some recent theory and research developments on the role and character of television, and its impact on learning in distance education. The implications for learning of distributional and social, control, and symbolic (audiovisual) characteristics of television are discussed. Fifteen references and an outline of television applications…

  6. Future Ready Learning: Reimagining the Role of Technology in Education. 2016 National Education Technology Plan

    Science.gov (United States)

    Thomas, Susan

    2016-01-01

    The National Education Technology Plan is the flagship educational technology policy document for the United States. The 2016 Plan, "Future Ready Learning: Reimagining the Role of Technology in Education," articulates a vision of equity, active use, and collaborative leadership to make everywhere, all-the-time learning possible. While…

  7. Learning Strategies and Learner Attitudes in the Massively Multiplayer Online Role-Playing Game Cube World

    Science.gov (United States)

    Goh, Shu Li

    2016-01-01

    The rapid progress of technology has revolutionized learning and in the field of computer assisted language learning, the use of digital games has expanded significantly. One type of game that has been attracting interest is massively multiplayer online role-playing games (henceforth MMORPGs). Recent research has drawn attention to the potential…

  8. A Description Grid to Support the Design of Learning Role-Play Games

    Science.gov (United States)

    Mariais, Christelle; Michau, Florence; Pernin, Jean-Philippe

    2012-01-01

    To strengthen the motivation of learners, the professional training sector is focusing more and more on game-based learning. In this context, the authors have become interested in the design of Learning Role-Play Game (LRPG) scenarios. The aim of this article is to improve the designers' confidence in the validity of the game-based learning…

  9. Designing a mobile learning game to investigate the impact of role-playing on helping behavior

    NARCIS (Netherlands)

    Schmitz, Birgit; Ternier, Stefaan; Klemke, Roland; Kalz, Marco; Specht, Marcus

    2013-01-01

    Schmitz, B., Ternier, S., Klemke, R., Kalz, M., & Specht, M. (2013). Designing a mobile learning game to investigate the impact of role-playing on helping behavior. In D. Hernández-Leo et al. (Eds.), Scaling up Learning for Sustained Impact. Proceedings of European Conference on Technology Enhanced

  10. Multi-Role Project (MRP): A New Project-Based Learning Method for STEM

    Science.gov (United States)

    Warin, Bruno; Talbi, Omar; Kolski, Christophe; Hoogstoel, Frédéric

    2016-01-01

    This paper presents the "Multi-Role Project" method (MRP), a broadly applicable project-based learning method, and describes its implementation and evaluation in the context of a Science, Technology, Engineering, and Mathematics (STEM) course. The MRP method is designed around a meta-principle that considers the project learning activity…

  11. The Role of Emotion in Informal Science Learning: Testing an Exploratory Model

    Science.gov (United States)

    Staus, Nancy L.; Falk, John H.

    2017-01-01

    Although there is substantial research on the effect of emotions on educational outcomes in the classroom, relatively little is known about how emotion affects learning in informal science contexts. We examined the role of emotion in the context of an informal science learning experience by utilizing a path model to investigate the relationships…

  12. Evaluating the Effectiveness Roles of Variables in the Novice Programmers Learning

    Science.gov (United States)

    Shi, Nianfeng; Cui, Wen; Zhang, Ping; Sun, Ximing

    2018-01-01

    This research applies the roles of variables to the novice programmers in the C language programming. The results are evaluated using the Structure of Observed Learning Outcomes (SOLO) taxonomy. The participants were divided into an experimental group and a control group. The students from the control group learned programming in the traditional…

  13. The Role of Humor in Learning Physics: A Study of Undergraduate Students

    Science.gov (United States)

    Berge, Maria

    2017-01-01

    We all know that they do it, but what do students laugh "about" when learning science together? Although research has shown that students do use humor when they learn science, the role of humor in science education has received little attention. In this study, undergraduate students' laughter during collaborative work in physics has been…

  14. Examining the Role of Emotional Intelligence between Organizational Learning and Adaptive Performance in Indian Manufacturing Industries

    Science.gov (United States)

    Pradhan, Rabindra Kumar; Jena, Lalatendu Kesari; Singh, Sanjay Kumar

    2017-01-01

    Purpose: The purpose of this study is to examine the relationship between organisational learning and adaptive performance. Furthermore, the study investigates the moderating role of emotional intelligence in the perspective of organisational learning for addressing adaptive performance of executives employed in manufacturing organisations.…

  15. THE BIGGS AND MOORE MODEL IN E-LEARNING: The Role of Motivation and Collaboration as Moderators

    Directory of Open Access Journals (Sweden)

    Matti J. HAVERILA

    2012-04-01

    Full Text Available The purpose of this paper is to report the findings of a research conducted to evaluate the effect of e-learning experience on students’ perceived learning outcomes, and more specifically the role of motivation and collaboration as moderators between the e-learning experience and the learning outcome. The perceived learning outcome was measured with whether the students perceived to learn more in e-learning vis-à-vis traditional learning context. The participants came from an undergraduate course at Tamk University of Applied Sciences in Tampere, Finland. The Biggs and Moore learning model indicates that the process variables (motivation and collaboration in this study have a mediating role. It was found out in this study, however, that these process variables have a moderating role rather than mediating role. Specific recommendations for the practitioners are provided, and implications for educators are discussed. Finally suggestions for further research on e-learning are provided.

  16. A fundamental role for context in instrumental learning and extinction

    OpenAIRE

    Bouton, Mark E.; Todd, Travis P.

    2014-01-01

    The purpose of this article is to review recent research that has investigated the effects of context change on instrumental (operant) learning. The first part of the article discusses instrumental extinction, in which the strength of a reinforced instrumental behavior declines when reinforcers are withdrawn. The results suggest that extinction of either simple or discriminated operant behavior is relatively specific to the context in which it is learned: As in prior studies of Pavlovian exti...

  17. What is the teachers’ role when students learn through design of learning games in a scaffolded gamified learning environment?

    DEFF Research Database (Denmark)

    Weitze, Charlotte Lærke

    The aim of this research project is to create a reusable and flexible gamified learning design where the students are learning subject matters through the design of digital learning games. The students are their own learning designers forming teams that create games. The teams also peer review...... how the use of pre-build learning games in education can be taken a step further into the building of learning games while implementing subject matters from curriculum, not only focussing on the creative game design process. The aim of the form of this learning design is to scaffold the novice....../ play test each others games as a way to qualify the learning taking place around as well as inside the games they are building. The discussion is focusing on how the chosen pedagogical approach is framed within the gamified environment as well as on how the teachers can guide and scaffold the learning...

  18. Time will tell: The role of mobile learning analytics in self-regulated learning

    NARCIS (Netherlands)

    Tabuenca, Bernardo; Kalz, Marco; Drachsler, Hendrik; Specht, Marcus

    2015-01-01

    This longitudinal study explores the effects of tracking and monitoring time devoted to learn with a mobile tool, on self-regulated learning. Graduate students (n = 36) from three different online courses used their own mobile devices to track how much time they devoted to learn over a period of

  19. Examining Hypermedia Learning: The Role of Cognitive Load and Self-Regulated Learning

    Science.gov (United States)

    Moos, Daniel

    2013-01-01

    Distinct theoretical perspectives, Cognitive Load Theory and Self-Regulated Learning (SRL) theory, have been used to examine individual differences the challenges faced with hypermedia learning. However, research has tended to use these theories independently, resulting in less robust explanations of hypermedia learning. This study examined the…

  20. The Role of Feedback Contingency in Perceptual Category Learning

    Science.gov (United States)

    Ashby, F. Gregory; Vucovich, Lauren E.

    2016-01-01

    Feedback is highly contingent on behavior if it eventually becomes easy to predict, and weakly contingent on behavior if it remains difficult or impossible to predict even after learning is complete. Many studies have demonstrated that humans and nonhuman animals are highly sensitive to feedback contingency, but no known studies have examined how feedback contingency affects category learning, and current theories assign little or no importance to this variable. Two experiments examined the effects of contingency degradation on rule-based and information-integration category learning. In rule-based tasks, optimal accuracy is possible with a simple explicit rule, whereas optimal accuracy in information-integration tasks requires integrating information from two or more incommensurable perceptual dimensions. In both experiments, participants each learned rule-based or information-integration categories under either high or low levels of feedback contingency. The exact same stimuli were used in all four conditions and optimal accuracy was identical in every condition. Learning was good in both high-contingency conditions, but most participants showed little or no evidence of learning in either low-contingency condition. Possible causes of these effects are discussed, as well as their theoretical implications. PMID:27149393

  1. The pervasive role of social learning in primate lifetime development.

    Science.gov (United States)

    Whiten, Andrew; van de Waal, Erica

    2018-01-01

    In recent decades, an accelerating research effort has exploited a substantial diversity of methodologies to garner mounting evidence for social learning and culture in many species of primate. As in humans, the evidence suggests that the juvenile phases of non-human primates' lives represent a period of particular intensity in adaptive learning from others, yet the relevant research remains scattered in the literature. Accordingly, we here offer what we believe to be the first substantial collation and review of this body of work and its implications for the lifetime behavioral ecology of primates. We divide our analysis into three main phases: a first phase of learning focused on primary attachment figures, typically the mother; a second phase of selective learning from a widening array of group members, including some with expertise that the primary figures may lack; and a third phase following later dispersal, when a migrant individual encounters new ecological and social circumstances about which the existing residents possess expertise that can be learned from. Collating a diversity of discoveries about this lifetime process leads us to conclude that social learning pervades primate ontogenetic development, importantly shaping locally adaptive knowledge and skills that span multiple aspects of the behavioral repertoire.

  2. An investigation of the role of background music in IVWs for learning

    OpenAIRE

    Richards, Debbie; Fassbender, Eric; Bilgin, Ayse; Thompson, William Forde

    2008-01-01

    Empirical evidence is needed to corroborate the intuitions of gamers and game developers in understanding the benefits of Immersive Virtual Worlds (IVWs) as a learning environment and the role that music plays within these environments. We report an investigation to determine if background music of the genre typically found in computer-based role-playing games has an effect on learning in a computer-animated history lesson about the Macquarie Lighthouse within an IVW. In Experiment 1, music s...

  3. The theoretical base of e-learning and its role in surgical education.

    Science.gov (United States)

    Evgeniou, Evgenios; Loizou, Peter

    2012-01-01

    The advances in Internet and computer technology offer many solutions that can enhance surgical education and increase the effectiveness of surgical teaching. E-learning plays an important role in surgical education today, with many e-learning projects already available on the Internet. E-learning is based on a mixture of educational theories that derive from behaviorist, cognitivist, and constructivist educational theoretical frameworks. CAN EDUCATIONAL THEORY IMPROVE E-LEARNING?: Conventional educational theory can be applied to improve the quality and effectiveness of e-learning. The theory of "threshold concepts" and educational theories on reflection, motivation, and communities of practice can be applied when designing e-learning material. E-LEARNING IN SURGICAL EDUCATION: E-learning has many advantages but also has weaknesses. Studies have shown that e-learning is an effective teaching method that offers high levels of learner satisfaction. Instead of trying to compare e-learning with traditional methods of teaching, it is better to integrate in e-learning elements of traditional teaching that have been proven to be effective. E-learning can play an important role in surgical education as a blended approach, combined with more traditional methods of teaching, which offer better face-to-interaction with patients and colleagues in different circumstances and hands on practice of practical skills. National provision of e-learning can make evaluation easier. The correct utilization of Internet and computer resources combined with the application of valid conventional educational theory to design e-learning relevant to the various levels of surgical training can be effective in the training of future surgeons. Copyright © 2012 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  4. Defects and defect processes in nonmetallic solids

    CERN Document Server

    Hayes, W

    2004-01-01

    This extensive survey covers defects in nonmetals, emphasizing point defects and point-defect processes. It encompasses electronic, vibrational, and optical properties of defective solids, plus dislocations and grain boundaries. 1985 edition.

  5. Selective role for DNMT3a in learning and memory.

    Science.gov (United States)

    Morris, Michael J; Adachi, Megumi; Na, Elisa S; Monteggia, Lisa M

    2014-11-01

    Methylation of cytosine nucleotides is governed by DNA methyltransferases (DNMTs) that establish de novo DNA methylation patterns in early embryonic development (e.g., DNMT3a and DNMT3b) or maintain those patterns on hemimethylated DNA in dividing cells (e.g., DNMT1). DNMTs continue to be expressed at high levels in mature neurons, however their impact on neuronal function and behavior are unclear. To address this issue we examined DNMT1 and DNMT3a expression following associative learning. We also generated forebrain specific conditional Dnmt1 or Dnmt3a knockout mice and characterized them in learning and memory paradigms as well as for alterations in long-term potentiation (LTP) and synaptic plasticity. Here, we report that experience in an associative learning task impacts expression of Dnmt3a, but not Dnmt1, in brain areas that mediate learning of this task. We also found that Dnmt3a knockout mice, and not Dnmt1 knockouts have synaptic alterations as well as learning deficits on several associative and episodic memory tasks. These findings indicate that the de novo DNA methylating enzyme DNMT3a in postmitotic neurons is necessary for normal memory formation and its function cannot be substituted by the maintenance DNA methylating enzyme DNMT1. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. THE ROLE OF STUDENT CHARACTERISTICS IN PROBLEM BASED LEARNING

    Directory of Open Access Journals (Sweden)

    Mia Damiyanti

    2006-04-01

    Full Text Available To reach the effectiveness of study, it is recommended to work on active learning method. The learning activity must be done with emphasis on the students’ characteristics. The characteristic means internal factors (cognitive entry behavior and affective entry characteristics, which are considered important as solving problems. The previous studies have shown that there is a correlation between achievement test and students’ characteristic entry behavior. At the beginning of the academic year of 2003, Faculty of Dentistry, University of Indonesia started active learning with PBL curriculum for the BDS degree. From a study about the correlation between the achievement and students’ entry behavior (previous knowledge, self concept, attitude, and anxiety during attending the test the study showed that characteristic entry behavior contributes to the student’s achievement test. The results supported the previous study.

  7. PREDICTING ACADEMIC ACHIEVEMENT: THE ROLE OF MOTIVATION AND LEARNING STRATEGIES

    Directory of Open Access Journals (Sweden)

    Juliana Beatriz Stover

    2014-04-01

    Full Text Available The aim of this study consists in testing a predictive model of academic achievement including motivation and learning strategies as predictors. Motivation is defined as the energy and the direction of behaviors; it is categorized in three types of motivation –intrinsic, extrinsic and amotivation (Deci & Ryan, 1985. Learning strategies are deliberate operations oriented towards information processing in academic activities (Valle, Barca, González & Núñez, 1999. Several studies analysed the relationship between motivation and learning strategies in high school and college environments. Students with higher academic achievement were intrinsically motivated and used a wider variety of learning strategies more frequently. A non-experimental predictive design was developed. The sample was composed by 459 students (55.2% high-schoolers; 44.8% college students. Data were gathered by means of sociodemographic and academic surveys, and also by the local versions of the Academic Motivation Scale –EMA, Echelle de Motivation en Éducation (Stover, de la Iglesia, Rial Boubeta & Fernández Liporace, 2012; Vallerand, Blais, Briere & Pelletier, 1989 and the Learning and Study Strategies Inventory –LASSI (Stover, Uriel & Fernández Liporace, 2012; Weinstein, Schulte & Palmer, 1987. Several path analyses were carried out to test a hypothetical model to predict academic achievement (Kline, 1998. Results indicated that self-determined motivation explained academic achievement through the use of learning strategies. The final model obtained an excellent fit (χ2=16.523, df= 6, p=0.011; GFI=0.987; AGFI=0.955; SRMR=0.0320; NFI=0.913; IFI=0.943; CFI=0.940. Results are discussed considering Self Determination Theory and previous research.

  8. Functional aging impairs the role of feedback in motor learning.

    Science.gov (United States)

    Liu, Yu; Cao, Chunmei; Yan, Jin H

    2013-10-01

    Optimal motor skill acquisition frequently requires augmented feedback or knowledge of results (KR). However, the effect of functional declines on the benefits of KR remains to be determined. The objective of this research was to examine how cognitive and motor deficits of older adults influence the use of KR for motor skill learning. A total of 57 older adults (mean 73.1 years; SD 4.2) received both cognitive and eye-hand coordination assessments, whereas 55 young controls (mean 25.8 years; SD 3.8) took only the eye-hand coordination test. All young and older participants learned a time-constrained arm movement through KR in three pre-KR and post-KR intervals. In the subsequent no-KR skill retests, absolute and variable time errors were not significantly reduced for the older learners who had KR during skill practice, especially for those with cognitive and motor dysfunctions. The finding suggests that KR results in no measureable improvement for older adults with cognitive and motor functional deficiencies. More importantly, for the older adults, longer post-KR intervals showed greater detrimental effects on feedback-based motor learning than shorter pauses after KR delivery. The findings support the hypothesis about the effects of cognitive and motor deficits on KR in motor skill learning of older adults. The dynamics of cognitive and motor aging, external feedback and internal control mechanisms collectively explain the deterioration in the sensory-motor learning of older adults. The theoretical implications and practical relevance of functional aging for motor skill learning are discussed. © 2013 Japan Geriatrics Society.

  9. The role of learning-related dopamine signals in addiction vulnerability.

    Science.gov (United States)

    Huys, Quentin J M; Tobler, Philippe N; Hasler, Gregor; Flagel, Shelly B

    2014-01-01

    Dopaminergic signals play a mathematically precise role in reward-related learning, and variations in dopaminergic signaling have been implicated in vulnerability to addiction. Here, we provide a detailed overview of the relationship between theoretical, mathematical, and experimental accounts of phasic dopamine signaling, with implications for the role of learning-related dopamine signaling in addiction and related disorders. We describe the theoretical and behavioral characteristics of model-free learning based on errors in the prediction of reward, including step-by-step explanations of the underlying equations. We then use recent insights from an animal model that highlights individual variation in learning during a Pavlovian conditioning paradigm to describe overlapping aspects of incentive salience attribution and model-free learning. We argue that this provides a computationally coherent account of some features of addiction. © 2014 Elsevier B.V. All rights reserved.

  10. [Role of the implicit theories of intelligence in learning situations].

    Science.gov (United States)

    Da Fonseca, D; Cury, F; Bailly, D; Rufo, M

    2004-01-01

    Most studies have tried to explain the school difficulties by analysing the intellectual factors that lead to school failure. However in addition to the instrumental capacities, authors also recognize the role played by other factors such as motivation. More specifically, the theory of achievement motivation aims to determine motivational factors involved in achievement situations when the students have to demonstrate their competencies. This paradigm attributes a central place to beliefs in order to explain children's behavior in academic situations. According to Dweck, it seems that beliefs about the nature of intelligence have a very powerful impact on behavior. These implicit theories of intelligence create a meaning system or conceptual framework that influences the individual interpretation of school situations. Thus, an entity theory of intelligence is the belief that intelligence is a fixed trait, a personal quality that cannot be changed. Students who subscribe to this theory believe that although people can learn new things, their underlying intelligence remains the same. In contrast, an incremental theory of intelligence is the belief that intelligence is a malleable quality that can increase through efforts. The identification of these two theories allows us to understand the cognition and behavior of individuals in achievement situations. Many studies carried out in the academic area show that students who hold an entity theory of intelligence (ie they consider intelligence like a stable quality) have a strong tendency to attribute their failures to a fixed trait. They are more likely to blame their intelligence for ne-gative outcomes and to attribute failures to their bad intellectual ability. In contrast, students who hold an incremental theory of intelligence (ie they consider intelligence as a malleable quality) are more likely to understand the same ne-gative outcomes in terms of specific factors: they attribute them to a lack of effort. This

  11. Improving health care quality and safety: the role of collective learning.

    Science.gov (United States)

    Singer, Sara J; Benzer, Justin K; Hamdan, Sami U

    2015-01-01

    Despite decades of effort to improve quality and safety in health care, this goal feels increasingly elusive. Successful examples of improvement are infrequently replicated. This scoping review synthesizes 76 empirical or conceptual studies (out of 1208 originally screened) addressing learning in quality or safety improvement, that were published in selected health care and management journals between January 2000 and December 2014 to deepen understanding of the role that collective learning plays in quality and safety improvement. We categorize learning activities using a theoretical model that shows how leadership and environmental factors support collective learning processes and practices, and in turn team and organizational improvement outcomes. By focusing on quality and safety improvement, our review elaborates the premise of learning theory that leadership, environment, and processes combine to create conditions that promote learning. Specifically, we found that learning for quality and safety improvement includes experimentation (including deliberate experimentation, improvisation, learning from failures, exploration, and exploitation), internal and external knowledge acquisition, performance monitoring and comparison, and training. Supportive learning environments are characterized by team characteristics like psychological safety, appreciation of differences, openness to new ideas social motivation, and team autonomy; team contextual factors including learning resources like time for reflection, access to knowledge, organizational capabilities; incentives; and organizational culture, strategy, and structure; and external environmental factors including institutional pressures, environmental dynamism and competitiveness and learning collaboratives. Lastly learning in the context of quality and safety improvement requires leadership that reinforces learning through actions and behaviors that affect people, such as coaching and trust building, and through

  12. Chemotherapeutic-Induced Cardiovascular Dysfunction: Physiological Effects, Early Detection—The Role of Telomerase to Counteract Mitochondrial Defects and Oxidative Stress

    Science.gov (United States)

    Quryshi, Nabeel; Norwood Toro, Laura E.; Ait-Aissa, Karima; Kong, Amanda; Beyer, Andreas M.

    2018-01-01

    Although chemotherapeutics can be highly effective at targeting malignancies, their ability to trigger cardiovascular morbidity is clinically significant. Chemotherapy can adversely affect cardiovascular physiology, resulting in the development of cardiomyopathy, heart failure and microvascular defects. Specifically, anthracyclines are known to cause an excessive buildup of free radical species and mitochondrial DNA damage (mtDNA) that can lead to oxidative stress-induced cardiovascular apoptosis. Therefore, oncologists and cardiologists maintain a network of communication when dealing with patients during treatment in order to treat and prevent chemotherapy-induced cardiovascular damage; however, there is a need to discover more accurate biomarkers and therapeutics to combat and predict the onset of cardiovascular side effects. Telomerase, originally discovered to promote cellular proliferation, has recently emerged as a potential mechanism to counteract mitochondrial defects and restore healthy mitochondrial vascular phenotypes. This review details mechanisms currently used to assess cardiovascular damage, such as C-reactive protein (CRP) and troponin levels, while also unearthing recently researched biomarkers, including circulating mtDNA, telomere length and telomerase activity. Further, we explore a potential role of telomerase in the mitigation of mitochondrial reactive oxygen species and maintenance of mtDNA integrity. Telomerase activity presents a promising indicator for the early detection and treatment of chemotherapy-derived cardiac damage. PMID:29534446

  13. Local Conduction in MoxW1–xSe2: The Role of Stacking Faults, Defects, and Alloying

    Science.gov (United States)

    2018-01-01

    Here, we report on the surface conductivity of WSe2 and MoxW1–xSe2 (0 ≤ x ≤ 1) crystals investigated with conductive atomic force microscopy. We found that stacking faults, defects, and chemical heterogeneities form distinct two-dimensional and one-dimensional conduction paths on the transition metal dichalcogenide surface. In the case of WSe2, in addition to step edges, we find a significant amount of stacking faults (formed during the cleaving process) that strongly influence the surface conductivity. These regions are attributed to the alternation of the 2H and 3R polytypism. The stacking faults form regular 2D patterns by alternation of the underlying stacking order, with a periodicity that varies significantly between different regions and samples. In the case of MoxW1–xSe2, its conductivity has a localized nature, which depends on the underlying chemical composition and the Mo/W ratio. Segregation to W-rich and Mo-rich regions during the growth process leads to nonuniform conduction paths on the surface of the alloy. We found a gradual change of the conductivity moving from one region to the other, reminiscent of lateral band bending. Our results demonstrate the use of C-AFM as a nanoscopic tool to probe the electrical properties of largely inhomogeneous samples and show the complicated nature of the surface conductivity of TMDC alloys. PMID:29578328

  14. Local Conduction in Mo xW1- xSe2: The Role of Stacking Faults, Defects, and Alloying.

    Science.gov (United States)

    Bampoulis, Pantelis; Sotthewes, Kai; Siekman, Martin H; Zandvliet, Harold J W

    2018-04-18

    Here, we report on the surface conductivity of WSe 2 and Mo x W 1- x Se 2 (0 ≤ x ≤ 1) crystals investigated with conductive atomic force microscopy. We found that stacking faults, defects, and chemical heterogeneities form distinct two-dimensional and one-dimensional conduction paths on the transition metal dichalcogenide surface. In the case of WSe 2 , in addition to step edges, we find a significant amount of stacking faults (formed during the cleaving process) that strongly influence the surface conductivity. These regions are attributed to the alternation of the 2H and 3R polytypism. The stacking faults form regular 2D patterns by alternation of the underlying stacking order, with a periodicity that varies significantly between different regions and samples. In the case of Mo x W 1- x Se 2 , its conductivity has a localized nature, which depends on the underlying chemical composition and the Mo/W ratio. Segregation to W-rich and Mo-rich regions during the growth process leads to nonuniform conduction paths on the surface of the alloy. We found a gradual change of the conductivity moving from one region to the other, reminiscent of lateral band bending. Our results demonstrate the use of C-AFM as a nanoscopic tool to probe the electrical properties of largely inhomogeneous samples and show the complicated nature of the surface conductivity of TMDC alloys.

  15. The Role of Subjective Task Value in Service-Learning Engagement among Chinese College Students

    Science.gov (United States)

    Li, Yulan; Guo, Fangfang; Yao, Meilin; Wang, Cong; Yan, Wenfan

    2016-01-01

    Most service-learning studies in higher education focused on its effects on students’ development. The dynamic processes and mechanisms of students’ development during service-learning, however, have not been explored thoroughly. Student engagement in service-learning may affect service-learning outcomes and be affected by subjective task value at the same time. The present study aimed to explore the effect of subjective task value on Chinese college student engagement during service-learning. Fifty-four Chinese college students participated in a 9-weeks service-learning program of interacting with children with special needs. Students’ engagement and subjective task value were assessed via self-report questionnaires and 433 weekly reflective journals. The results indicated that the cognitive, emotional and behavioral engagement of Chinese college students demonstrated different developmental trends during service-learning process. Subjective task value played an essential role in student engagement in service-learning activities. However, the role of subjective task value varied with different stages. Finally, the implications for implementing service-learning in Chinese education were discussed. PMID:27445919

  16. The Role of Subjective Task Value in Service-Learning Engagement among Chinese College Students.

    Science.gov (United States)

    Li, Yulan; Guo, Fangfang; Yao, Meilin; Wang, Cong; Yan, Wenfan

    2016-01-01

    Most service-learning studies in higher education focused on its effects on students' development. The dynamic processes and mechanisms of students' development during service-learning, however, have not been explored thoroughly. Student engagement in service-learning may affect service-learning outcomes and be affected by subjective task value at the same time. The present study aimed to explore the effect of subjective task value on Chinese college student engagement during service-learning. Fifty-four Chinese college students participated in a 9-weeks service-learning program of interacting with children with special needs. Students' engagement and subjective task value were assessed via self-report questionnaires and 433 weekly reflective journals. The results indicated that the cognitive, emotional and behavioral engagement of Chinese college students demonstrated different developmental trends during service-learning process. Subjective task value played an essential role in student engagement in service-learning activities. However, the role of subjective task value varied with different stages. Finally, the implications for implementing service-learning in Chinese education were discussed.

  17. An interactive approach for new careers: The role of learning opportunities and learning behavior

    OpenAIRE

    van der Sluis, E.C.; Peiperl, M.A.

    2000-01-01

    This study examined the learning process at work from an individual perspective. Different kinds of learning opportunities and learning behavior were examined as (a) predictors of career development and (b) moderators of the development process on the job. Survey data from early-career MBAs were analyzed by performing hierarchical regressions and difference-of-means tests. Results indicated that the total amount of developmental job opportunities has a positive influence on individual percept...

  18. Forging Professional Learning Communities: The Role of External Agency

    Science.gov (United States)

    Sperandio, Jill; Kong, Peggy A.

    2018-01-01

    This article explored the effects of external agency on the establishment of professional learning communities (PLCs). The research was undertaken in the context of schools that have chosen to adopt the Primary Years Programme (PYP) of the International Baccalaureate (IB) worldwide. The study employed a two-stage qualitative sequential design…

  19. Geoscience Videos and Their Role in Supporting Student Learning

    Science.gov (United States)

    Wiggen, Jennifer; McDonnell, David

    2017-01-01

    A series of short (5 to 7 minutes long) geoscience videos were created to support student learning in a flipped class setting for an introductory geology class at North Carolina State University. Videos were made using a stylus, tablet, microphone, and video editing software. Essentially, we narrate a slide, sketch a diagram, or explain a figure…

  20. The Role of First Impression in Operant Learning

    Science.gov (United States)

    Shteingart, Hanan; Neiman, Tal; Loewenstein, Yonatan

    2013-01-01

    We quantified the effect of first experience on behavior in operant learning and studied its underlying computational principles. To that goal, we analyzed more than 200,000 choices in a repeated-choice experiment. We found that the outcome of the first experience has a substantial and lasting effect on participants' subsequent behavior, which we…

  1. Statistical learning of action: the role of conditional probability.

    Science.gov (United States)

    Meyer, Meredith; Baldwin, Dare

    2011-12-01

    Identification of distinct units within a continuous flow of human action is fundamental to action processing. Such segmentation may rest in part on statistical learning. In a series of four experiments, we examined what types of statistics people can use to segment a continuous stream involving many brief, goal-directed action elements. The results of Experiment 1 showed no evidence for sensitivity to conditional probability, whereas Experiment 2 displayed learning based on joint probability. In Experiment 3, we demonstrated that additional exposure to the input failed to engender sensitivity to conditional probability. However, the results of Experiment 4 showed that a subset of adults-namely, those more successful at identifying actions that had been seen more frequently than comparison sequences-were also successful at learning conditional-probability statistics. These experiments help to clarify the mechanisms subserving processing of intentional action, and they highlight important differences from, as well as similarities to, prior studies of statistical learning in other domains, including language.

  2. The Role of Parenting in Children's Self-Regulated Learning

    Science.gov (United States)

    Pino-Pasternak, Deborah; Whitebread, David

    2010-01-01

    This paper reports the results of a systematic literature review on empirical studies exploring relationships between parental behaviours and children's self-regulated learning (SRL). The literature search resulted in 22 studies published between 1980 and 2009. Studies were analysed in terms of their research findings and their methodological…

  3. Examining the role of social cues in early word learning.

    Science.gov (United States)

    Briganti, Alicia M; Cohen, Leslie B

    2011-02-01

    Infants watched a video of an adult pointing towards two different objects while hearing novel labels. Analyses indicated that 14- and 18-month-olds looked longer at the target object, but only 18-month-olds showed word learning. The results suggest that different types of social cues are available at different ages. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. The Learning Teacher: Role of Ambiguity in Education

    Science.gov (United States)

    Suzawa, Gilbert S.

    2013-01-01

    Life is full of ambiguities, but as teachers we generally try to teach our students in a manner that sanitizes knowledge of all of its ambiguities. In doing so, we create an educational environment which forces students to learn in a rather meaningless fashion and this in turn leads to a lack of vitality and relevance within the academy. This need…

  5. Informal Learning in Music: Emerging Roles of Teachers and Students

    Science.gov (United States)

    Rodriguez, Carlos

    2009-01-01

    In her new book "Music, Informal Learning and the School" (2008), Lucy Green consolidates many ideas presented in her previous writings. There is little doubt of the significance of her approach, but it raises epistemological and pedagogical issues that must be addressed to better understand where music teachers go next with informal…

  6. The role of learning and social interaction for changing practices

    DEFF Research Database (Denmark)

    Christensen, Toke Haunstrup

    The paper presents initial theoretical suggestions on how practice theory might be combined with understandings of learning as an experiential and social activity. The aim is to inspire to further thinking about how to make practice theory more “applicable” for designing changes towards a low...

  7. Role of Service Learning in Water Quality Studies

    Science.gov (United States)

    Richards, Wilfred Sugumar

    2009-01-01

    Background: Chemistry students often complain that they are unmotivated because they see no applications of chemical principles in "real life." It was thus decided to put into use the knowledge gained during the course on water quality and analysis. Learning the principles of quantitative chemical analysis requires innovative, hands-on…

  8. Teachers' Professional Learning: The Role of Knowledge Management Practices

    Science.gov (United States)

    Niehoff, Karissa

    2010-01-01

    This qualitative study explored the degree to which knowledge management strategies addressed teacher professional learning at the high school level. In the setting of a Connecticut public high school, interviews were conducted which explored teacher perceptions of knowledge sharing practices in the school and how those practices influenced their…

  9. Learning in the Knowledge Economy: The Role of Technology

    Science.gov (United States)

    Jaffrin, Manuel

    2003-01-01

    Internet is not the panacea for every problem in education but we must realize that this is a great tool that can help us empower every student and elevate each individual to new levels of intellectual capacity and skills. Combined with specifics learning objectives, it will definitely change the face of education. Technology is becoming an…

  10. The Role of Multicultural Information in Experiential Learning

    Science.gov (United States)

    Shen, Lan

    2011-01-01

    This paper is based on the author's empirical experience in assisting cultural immersion programs through developing multicultural collections, promoting diversity resources, and creating a supportive information environment for faculty and students. After summarizing the significance, goals, learning objectives, and program models of cultural…

  11. Understanding the Roles of Families in Virtual Learning

    Science.gov (United States)

    Currie-Rubin, Rachel; Smith, Sean J.

    2014-01-01

    Families choose to enroll their children in fully online schools for many reasons. Online schools offer the possibility of flexible schedules and the potential to learn at a pace and in a manner that is not available to students in their brick-and-mortar schools (Cavanaugh & Clark, 2007). Because online education can allow for individualized…

  12. Roles of Technology in Student Learning of University Level Biostatistics

    Science.gov (United States)

    Xu, Weili; Zhang, Yuchen; Su, Cheng; Cui, Zhuang; Qi, Xiuying

    2014-01-01

    This study explored threshold concepts and areas of troublesome knowledge among students enrolled in a basic biostatistics course at the university level. The main area of troublesome knowledge among students was targeted by using technology to improve student learning. A total of 102 undergraduate students who responded to structured…

  13. Trust, Caring and Organizational Learning: The Leader's Role

    Science.gov (United States)

    Louis, Karen Seashore; Murphy, Joseph

    2017-01-01

    Purpose: The purpose of this paper is to investigate whether principals can have an impact on organizational learning (OL). The authors use a cultural perspective, based both in the emerging literature from positive psychology and the relatively well-developed research tradition in studying the nature and impacts of OL to address four questions:…

  14. E-Learning and Role of World Wide Web in E-Learning

    OpenAIRE

    Jahankhani, Hossein

    2012-01-01

    This paper reviews some of the aspects of the E-learning through the World Wide Web. E-revolution as new phenomenon influenced the society by its means and strategies. E-learning is one of the sub-products of E-revolution, towards making more convenient and effective learning. In time Internet become a source of information, people start to learn through the Internet instead of books. It gives the flexibility to remote access at any time. The working people and the students are inspired by th...

  15. A Study to Understand the Role of Visual Arts in the Teaching and Learning of Science

    Science.gov (United States)

    Dhanapal, Saroja; Kanapathy, Ravi; Mastan, Jamilah

    2014-01-01

    This research was carried out to understand the role of visual arts in the teaching and learning of science among Grade 3 teachers and students. A mixture of qualitative and quantitative research design was used to discover the different perceptions of both teachers and students on the role of visual arts in science. The data for the research was…

  16. Role of Mobile Technology in Promoting Campus-Wide Learning Environment

    Science.gov (United States)

    Hussain, Irshad; Adeeb, Muhammad Aslam

    2009-01-01

    The present study examines the role of mobile technology in promoting campus-wide learning environment. Its main objectives were to a) evaluate the role of mobile technology in higher education in terms of its i). appropriateness ii). flexibility iii). Interactivity, & iv). availability & usefulness and to b). identify the problems of…

  17. E-learning Constructive Role Plays for EFL Learners in China's Tertiary Education

    Science.gov (United States)

    Shen, Lin; Suwanthep, Jitpanat

    2011-01-01

    Recently, speaking has played an increasingly important role in second/foreign language settings. However, in many Chinese universities, EFL students rarely communicate in English with other people effectively. The existing behavioristic role plays on New Horizon College English (NHCE) e-learning do not function successfully in supplementing EFL…

  18. Perceptions of Challenge: The Role of Catastrophe Theory in Piano Learning

    Science.gov (United States)

    Bugos, Jennifer; Lee, William

    2015-01-01

    The purpose of this study is to evaluate the perceptions of private piano instructors on the role of challenge in teaching and learning the piano and to examine the potential application of catastrophe theory in understanding the role and outcomes of such challenges. A 23-item electronic questionnaire was administered to collect quantitative and…

  19. The Role of Metacognitive Strategies in Learning Music: A Multiple Case Study

    Science.gov (United States)

    Colombo, Barbara; Antonietti, Alessandro

    2017-01-01

    The positive role of metacognition in music learning and practice is well assessed, but the role of musicians' metacognitive skills in such a context is not yet clear. Teachers often state that they apply a metacognitive approach during their lessons, but students fail to acknowledge it and report that they become metacognitive learners thanks to…

  20. Using a Corporate Partnership to Enhance Learning in a Sourcing Negotiation Role-play

    Science.gov (United States)

    Hartley, Janet L.; Eboch, Karen; Gilberg, Jonathan

    2017-01-01

    Although role-plays can be effective teaching tools for buyer-supplier negotiation, learning can be somewhat limited because typically novices are negotiating with each other. We describe how we collaborated with a corporate partner, CACI International, to develop and implement a repeatable sourcing and negotiation role-play that helps to address…

  1. Role-Play in Literature Lectures: The Students' Assessment of Their Learning

    Science.gov (United States)

    Riain, Isobel Ní; Dawson, Ciarán; McCarthy, Marian

    2018-01-01

    The following article is based on a piece of qualitative research on the use of role-play in a literature module in the Modern Irish Dept. of University College Cork, Ireland, in 2015. There were 18 students involved in the research. The aim of the research was to investigate if students associate learning with the use of role-play in literature…

  2. Work Engagement: Antecedents, the Mediating Role of Learning Goal Orientation and Job Performance

    Science.gov (United States)

    Chughtai, Aamir Ali; Buckley, Finian

    2011-01-01

    Purpose: The present paper aims to explore the effects of state (trust in supervisor) and trait (trust propensity) trust on employees' work engagement. Furthermore, it seeks to investigate the mediating role of learning goal orientation in the relationship between work engagement and two forms of performance: in-role job performance and innovative…

  3. The Role of Motivation in Self-regulated Learning and Language Learning Strategy: In the Case of Chinese EFL Learners

    Directory of Open Access Journals (Sweden)

    Maryam Banisaeid

    2015-09-01

    Full Text Available Although self-regulation, derived from educational psychology, is a new topic in the second language learning field, language learning strategy was the main focus of many studies in the last two decades. Also, among the L2 individual differences, motivation plays an important role in achieving the educational goals. In this research, motivation is investigated from self-determination theory by which five types of motivation are presented. No study was found to investigate the role of motivation in both self-regulation and language learning strategy. For such a purpose, 49 Chinese EFL learners respond to SILL, MSLQ and LLOS_IEA respectively proposed by Oxford (1990, Pintrich et al (1991 and Noel et al (2000. The results running Pearson correlation showed that there is a significant relationship between motivation, self-regulation and language learning strategies. It is also revealed that Chinese EFL learners use memory, social and affective strategy more than the other ones. The most common motivational orientation is identified regulation. Among self-regulated learning strategies, effort regulation is highly used by them. At the end some implication is considered.

  4. How do we learn to "kill" in volleyball?: The role of working memory capacity and expertise in volleyball motor learning.

    Science.gov (United States)

    Bisagno, Elisa; Morra, Sergio

    2018-03-01

    This study examines young volleyball players' learning of increasingly complex attack gestures. The main purpose of the study was to examine the predictive role of a cognitive variable, working memory capacity (or "M capacity"), in the acquisition and development of motor skills in a structured sport. Pascual-Leone's theory of constructive operators (TCO) was used as a framework; it defines working memory capacity as the maximum number of schemes that can be simultaneously activated by attentional resources. The role of expertise in motor learning was also considered. The expertise of each athlete was assessed in terms of years of practice and number of training sessions per week. The participants were 120 volleyball players, aged between 6 and 26 years, who performed both working memory tests and practical tests of volleyball involving the execution of the "third touch" by means of technical gestures of varying difficulty. We proposed a task analysis of these different gestures framed within the TCO. The results pointed to a very clear dissociation. On the one hand, M capacity was the best predictor of correct motor performance, and a specific capacity threshold was found for learning each attack gesture. On the other hand, experience was the key for the precision of the athletic gestures. This evidence could underline the existence of two different cognitive mechanisms in motor learning. The first one, relying on attentional resources, is required to learn a gesture. The second one, based on repeated experience, leads to its automatization. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. How Teachers Learn: The Roles of Formal, Informal, and Independent Learning

    Science.gov (United States)

    Jones, W. Monty; Dexter, Sara

    2014-01-01

    A qualitative study of math and science teachers at two middle schools identifies how their system for learning to integrate technology into their teaching goes beyond what school leaders typically consider when planning for teachers' learning. In addition to (a) the district-initiated, or formal, system of professional development (PD) and…

  6. The Role of Gender in Foreign Language Learning Attitudes: Japanese Female Students' Attitudes towards English Learning.

    Science.gov (United States)

    Kobayashi, Yoko

    2002-01-01

    Analyzed data from research on Japanese high school students' attitudes toward learning English to investigate female students' more positive attitudes toward English learning. Girls' attitudes toward English were affected by a composite of Japanese social and educational elements (e.g., characterization of English as a woman-dominant choice at…

  7. The Role of Statistical Learning and Working Memory in L2 Speakers' Pattern Learning

    Science.gov (United States)

    McDonough, Kim; Trofimovich, Pavel

    2016-01-01

    This study investigated whether second language (L2) speakers' morphosyntactic pattern learning was predicted by their statistical learning and working memory abilities. Across three experiments, Thai English as a Foreign Language (EFL) university students (N = 140) were exposed to either the transitive construction in Esperanto (e.g., "tauro…

  8. Relationship between Individual and Organizational Learning: Mediating Role of Team Learning

    Directory of Open Access Journals (Sweden)

    Monika Stelmaszczyk

    2016-12-01

    Full Text Available The aim of this paper is to recognize the relationships between individual and organizational learning while considering team learning as a mediator of these relationships. The research object is a large Polish enterprise specializing in the production of cast-iron items. In order to test assumed research hypotheses, statistical analyses were conducted using the IBM SPSS Statistics Suite, version 20. The suite helped conduct correlation analyses concatenation, line regression analyses and mediation analyses using the PROCESS macro by Hayes and Preacher. The research results show a statistically significant relationship between individual learning and each of the five dimensions of organizational learning [clarity of purpose and mission; leadership commitment and empowerment; knowledge transfer; experimentation and rewards; and teamwork and group problem solving]. What is more, they prove that team learning is a mediator of a relationship between individual and organizational learning. Interestingly, only one full mediation has been observed while researching the mediative effect of team learning in relation to each out of the five dimensions of organizational learning. It occurred in relation to experimentation and rewards. In the remaining cases these were partial mediations.

  9. Variability in Second Language Learning: The Roles of Individual Differences, Learning Conditions, and Linguistic Complexity

    Science.gov (United States)

    Tagarelli, Kaitlyn M.; Ruiz, Simón; Vega, José Luis Moreno; Rebuschat, Patrick

    2016-01-01

    Second language learning outcomes are highly variable, due to a variety of factors, including individual differences, exposure conditions, and linguistic complexity. However, exactly how these factors interact to influence language learning is unknown. This article examines the relationship between these three variables in language learners.…

  10. The Role Of Teachers In Editing And Authoring Units Of Learning Using IMS Learning Design

    NARCIS (Netherlands)

    Griffiths, David; Blat, Josep

    2006-01-01

    The UNFOLD project, funded by the European Commission, runs a Community of Practice for Teachers and Learning Providers that has examined the way in which teachers can work with the IMS Learning Design Specification. The results of this work are presented. Relevant aspects of the specification are

  11. Exploring the Moderating Role of Perceived Flexibility Advantages in Mobile Learning Continuance Intention (MLCI

    Directory of Open Access Journals (Sweden)

    Rui-Ting Huang

    2014-07-01

    Full Text Available The primary purpose of this study was to explore the key factors that could affect mobile learning continuance intention (MLCI, and examine the moderating effect of perceived flexibility advantages (PFA on the relationship between key mobile learning elements and continuance intention. Five hundred undergraduate students who had previously adopted mobile devices to learn English took part in this study. Partial least squares (PLS analysis was utilized to test the hypotheses in this study. It has been found that the perceived usefulness of mobile technology, subjective norm, and self-management of learning could be closely linked to mobile learning continuance intention. With particular respect to the moderating role of perceived flexibility advantages, it has been demonstrated that PFA could moderate the relationship between perceived usefulness of mobile technology and mobile learning continuance intention, as well as the association between subjective norm and mobile learning continuance intention, whereas PFA did not moderate the link between self-management of learning and mobile learning continuance intention.This report has further added to the body of knowledge in the field of mobile learning through empirical examination.

  12. The amygdala complex: multiple roles in associative learning and attention.

    OpenAIRE

    Gallagher, M; Holland, P C

    1994-01-01

    Although certain neurophysiological functions of the amygdala complex in learning seem well established, the purpose of this review is to propose that an additional conceptualization of amygdala function is now needed. The research we review provides evidence that a subsystem within the amygdala provides a coordinated regulation of attentional processes. An important aspect of this additional neuropsychology of the amygdala is that it may aid in understanding the importance of connections bet...

  13. Society, family and learning. The role of home literacy environments

    OpenAIRE

    Querejeta, Maira

    2010-01-01

    This paper explores the relation between society, family, and learning. In particular, it addresses the features of home literacy environments in low income families and their impact on children's pre-literacy skills and knowledge. Sixty-two four/five-year-old children and their mothers were randomly selected for this study. The mothers were interviewed using an adaptation of a family literacy environment survey (Whitehurst, 1992). The children were assessed with specific tests to examine the...

  14. Role of classical conditioning in learning gastrointestinal symptoms

    OpenAIRE

    Stockhorst, Ursula; Enck, Paul; Klosterhalfen, Sibylle

    2007-01-01

    Nausea and/or vomiting are aversive gastrointestinal (GI) symptoms. Nausea and vomiting manifest unconditionally after a nauseogenic experience. However, there is correlative, quasiexperimental and experimental evidence that nausea and vomiting can also be learned via classical (Pavlovian) conditioning and might occur in anticipation of the nauseogenic event. Classical conditioning of nausea can develop with chemotherapy in cancer patients. Initially, nausea and vomiting occur during and afte...

  15. Learning, memory, and the role of neural network architecture.

    Directory of Open Access Journals (Sweden)

    Ann M Hermundstad

    2011-06-01

    Full Text Available The performance of information processing systems, from artificial neural networks to natural neuronal ensembles, depends heavily on the underlying system architecture. In this study, we compare the performance of parallel and layered network architectures during sequential tasks that require both acquisition and retention of information, thereby identifying tradeoffs between learning and memory processes. During the task of supervised, sequential function approximation, networks produce and adapt representations of external information. Performance is evaluated by statistically analyzing the error in these representations while varying the initial network state, the structure of the external information, and the time given to learn the information. We link performance to complexity in network architecture by characterizing local error landscape curvature. We find that variations in error landscape structure give rise to tradeoffs in performance; these include the ability of the network to maximize accuracy versus minimize inaccuracy and produce specific versus generalizable representations of information. Parallel networks generate smooth error landscapes with deep, narrow minima, enabling them to find highly specific representations given sufficient time. While accurate, however, these representations are difficult to generalize. In contrast, layered networks generate rough error landscapes with a variety of local minima, allowing them to quickly find coarse representations. Although less accurate, these representations are easily adaptable. The presence of measurable performance tradeoffs in both layered and parallel networks has implications for understanding the behavior of a wide variety of natural and artificial learning systems.

  16. Understanding the Role of Achievements in Game-Based Learning

    Directory of Open Access Journals (Sweden)

    Lucas Blair

    2016-12-01

    Full Text Available The objective of the current research was to examine whether one potentially effective gaming strategy—achievements—has a positive impact on learning in a game-based environment. An achievement in a video game is a reward or recognition earned by players for an in-game accomplishment. This paper describes a series of studies to evaluate the effects of achievement types on learning in a game designed to teach about health resources. The Game “Phone Dash” was used as the testbed for the following studies. The following questionnaires were utilized in this study: Video Game Self-Efficacy Scale (VGSES questionnaire, Relevance and Usefulness questionnaire, Game Engagement Questionnaire (GEQ, and the Intrinsic Motivation Inventory (IMI. Four studies were conducted. Results indicated that while in unison, the achievements were not as potent in motivating performance, certainly when combined they produced measurable changes in behavior. The four studies described in this paper provide important information regarding the optimal design of achievements in game-based health education. Developers of future game-based learning can use this information to enhance the potential effectiveness of their products. 

  17. The role of the basal ganglia in learning and memory: Insight from Parkinson's disease

    Science.gov (United States)

    2013-01-01

    It has long been known that memory is not a single process. Rather, there are different kinds of memory that are supported by distinct neural systems. This idea stemmed from early findings of dissociable patterns of memory impairments in patients with selective damage to different brain regions. These studies highlighted the role of the basal ganglia in non-declarative memory, such as procedural or habit learning, contrasting it with the known role of the medial temporal lobes in declarative memory. In recent years, major advances across multiple areas of neuroscience have revealed an important role for the basal ganglia in motivation and decision making. These findings have led to new discoveries about the role of the basal ganglia in learning and highlighted the essential role of dopamine in specific forms of learning. Here we review these recent advances with an emphasis on novel discoveries from studies of learning in patients with Parkinson's disease. We discuss how these findings promote the development of current theories away from accounts that emphasize the verbalizability of the contents of memory and towards a focus on the specific computations carried out by distinct brain regions. Finally, we discuss new challenges that arise in the face of accumulating evidence for dynamic and interconnected memory systems that jointly contribute to learning. PMID:21945835

  18. The role of the basal ganglia in learning and memory: insight from Parkinson's disease.

    Science.gov (United States)

    Foerde, Karin; Shohamy, Daphna

    2011-11-01

    It has long been known that memory is not a single process. Rather, there are different kinds of memory that are supported by distinct neural systems. This idea stemmed from early findings of dissociable patterns of memory impairments in patients with selective damage to different brain regions. These studies highlighted the role of the basal ganglia in non-declarative memory, such as procedural or habit learning, contrasting it with the known role of the medial temporal lobes in declarative memory. In recent years, major advances across multiple areas of neuroscience have revealed an important role for the basal ganglia in motivation and decision making. These findings have led to new discoveries about the role of the basal ganglia in learning and highlighted the essential role of dopamine in specific forms of learning. Here we review these recent advances with an emphasis on novel discoveries from studies of learning in patients with Parkinson's disease. We discuss how these findings promote the development of current theories away from accounts that emphasize the verbalizability of the contents of memory and towards a focus on the specific computations carried out by distinct brain regions. Finally, we discuss new challenges that arise in the face of accumulating evidence for dynamic and interconnected memory systems that jointly contribute to learning. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Observer roles that optimise learning in healthcare simulation education: a systematic review.

    Science.gov (United States)

    O'Regan, Stephanie; Molloy, Elizabeth; Watterson, Leonie; Nestel, Debra

    2016-01-01

    Simulation is widely used in health professional education. The convention that learners are actively involved may limit access to this educational method. The aim of this paper is to review the evidence for learning methods that employ directed observation as an alternative to hands-on participation in scenario-based simulation training. We sought studies that included either direct comparison of the learning outcomes of observers with those of active participants or identified factors important for the engagement of observers in simulation. We systematically searched health and education databases and reviewed journals and bibliographies for studies investigating or referring to observer roles in simulation using mannequins, simulated patients or role play simulations. A quality framework was used to rate the studies. We sought studies that included either direct comparison of the learning outcomes of observers with those of active participants or identified factors important for the engagement of observers in simulation. We systematically searched health and education databases and reviewed journals and bibliographies for studies investigating or referring to observer roles in simulation using mannequins, simulated patients or role play simulations. A quality framework was used to rate the studies. Nine studies met the inclusion criteria. Five studies suggest learning outcomes in observer roles are as good or better than hands-on roles in simulation. Four studies document learner satisfaction in observer roles. Five studies used a tool to guide observers. Eight studies involved observers in the debrief. Learning and satisfaction in observer roles is closely associated with observer tools, learner engagement, role clarity and contribution to the debrief. Learners that valued observer roles described them as affording an overarching view, examination of details from a distance, and meaningful feedback during the debrief. Learners who did not value observer roles

  20. A central role for the small GTPase Rac1 in hippocampal plasticity and spatial learning and memory

    DEFF Research Database (Denmark)

    Haditsch, Ursula; Leone, Dino P; Farinelli, Mélissa

    2009-01-01

    in excitatory neurons in the forebrain in vivo not only affects spine structure, but also impairs synaptic plasticity in the hippocampus with consequent defects in hippocampus-dependent spatial learning. Furthermore, Rac1 mutants display deficits in working/episodic-like memory in the delayed matching...

  1. Role of the hippocampus on learning and memory functioning and pain modulation

    Institute of Scientific and Technical Information of China (English)

    Haimei Wang

    2008-01-01

    The hippocampus, an important part of the limbic system, is considered to be an important region of the brain for learning and memory functioning. Recent studies have demonstrated that synaptic plasticity is thought to be the basis of learning and memory functioning. A series of studies report that similar synaptic plasticity also exists in the spinal cord in the conduction pathway of pain sensation, which may contribute to hyperalgesia, abnormal pain, and analgesia. The synaptic plasticity of learning and memory functioning and that of the pain conduction pathway have similar mechanisms, which are related to the N-methyl-D-aspartic acid receptor. The hippocampus also has a role in pain modulation. As pain signals can reach the hippocampus, the precise correlation between synaptic plasticity of the pain pathway and that of learning and memory functioning deserves further investigation. The role of the hippocampus in processing pain information requires to be identified.

  2. Role of e-learning information systems in regional development

    Directory of Open Access Journals (Sweden)

    Maria ANDRONIE

    2010-09-01

    The Information Communication Technology – ICT, an useful strategy for the education system improvement, is a means enabling the students develop their fundamental knowledge and the necessary competences in various fields in a knowledge-based economy. Computer skills become a “must”. We need to understand the way to improve the education system of an institution by implementing these technologies, in general, and the e-Learning systems, in particular. In this context, the information systems are the driver of a global education.

  3. The Roles of Phasic and Tonic Dopamine in Tic Learning and Expression.

    Science.gov (United States)

    Maia, Tiago V; Conceição, Vasco A

    2017-09-15

    Tourette syndrome (TS) prominently involves dopaminergic disturbances, but the precise nature of those disturbances has remained elusive. A substantial body of empirical work and recent computational models have characterized the specific roles of phasic and tonic dopamine (DA) in action learning and selection, respectively. Using insights from this work and models, we suggest that TS involves increases in both phasic and tonic DA, which produce increased propensities for tic learning and expression, respectively. We review the evidence from reinforcement-learning and habit-learning studies in TS, which supports the idea that TS involves increased phasic DA responses; we also review the evidence that tics engage the habit-learning circuitry. On the basis of these findings, we suggest that tics are exaggerated, maladaptive, and persistent motor habits reinforced by aberrant, increased phasic DA responses. Increased tonic DA amplifies the tendency to execute learned tics and also provides a fertile ground of motor hyperactivity for tic learning. We review evidence suggesting that antipsychotics may counter both the increased propensity for tic expression, by increasing excitability in the indirect pathway, and the increased propensity for tic learning, by shifting plasticity in the indirect pathway toward long-term potentiation (and possibly also through more complex mechanisms). Finally, we review evidence suggesting that low doses of DA agonists that effectively treat TS decrease both phasic and tonic DA, thereby also reducing the propensity for both tic learning and tic expression, respectively. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Role of Adult Learning Theories in the Development of Corporate Training in the USA

    Directory of Open Access Journals (Sweden)

    Iryna Lytovchenko

    2016-07-01

    Full Text Available The article presents the analysis of the role of adult learning theories in the development of corporate training in the USA. Considering that corporate education is part of the adult education system in this country, the author examines theories of organizational learning in the context of adult learning. The results of the study have revealed that adult education in the US is based on dif erent learning theories which should be viewed from the perspective of several main orientations: behaviorism, cognitivism, humanism, developmental theories, social learning, constructivism, which have dif erent philosophical background and, accordingly, different understanding of the nature and methodology of adult learning. Based on the results of the study it has been concluded that theories of organizational learning which explain motivation of students, their needs and goals, cognitive processes and other aspects of the learning in organizations and have had the main influence on the development of corporate education in the United States should be viewed in the context of the above-mentioned basic orientations to learning, too. From the methodological perspective, the research was based on interdisciplinary and systemic approaches. Thus, we used a set of interrelated research methods: comparative, structural, systemic-functional analyses, comparison and synthesis.

  5. Relationship between Individual and Organizational Learning: Mediating Role of Team Learning

    OpenAIRE

    Monika Stelmaszczyk

    2016-01-01

    The aim of this paper is to recognize the relationships between individual and organizational learning while considering team learning as a mediator of these relationships. The research object is a large Polish enterprise specializing in the production of cast-iron items. In order to test assumed research hypotheses, statistical analyses were conducted using the IBM SPSS Statistics Suite, version 20. The suite helped conduct correlation analyses concatenation, line regression analyses and med...

  6. Adults learning Finnish as a foreign language : role of support, emotions and reasons connected with learning

    OpenAIRE

    MacKenzie, Ashley

    2015-01-01

    The purpose of this research study was to examine adults learning Finnish as a foreign language while striving to understand the reasons behind their decisions to do so, the support that was individually offered to the participants, how they felt throughout the learning process, and whether or not they found themselves to be self-reliant learners, as per Knowles’ andragogy theory. This study set out to examine adult language learners participating in the language and integration program at Pa...

  7. The Mediating Role of Organizational Learning in?the Relationship of Organizational Intelligence and Organizational Agility

    OpenAIRE

    Bahrami, Mohammad Amin; Kiani, Mohammad Mehdi; Montazeralfaraj, Raziye; Zadeh, Hossein Fallah; Zadeh, Morteza Mohammad

    2016-01-01

    Objectives Organizational learning is defined as creating, absorbing, retaining, transferring, and application of knowledge within an organization. This article aims to examine the mediating role of organizational learning in the relationship of organizational intelligence and organizational agility. Methods This analytical and cross-sectional study was conducted in 2015 at four teaching hospitals of Yazd city, Iran. A total of 370 administrative and medical staff contributed to the study. We...

  8. Role of state-dependent learning in the cognitive effects of caffeine in mice

    OpenAIRE

    Sanday, Leandro [UNIFESP; Zanin, Karina Agustini [UNIFESP; Patti, Camilla de Lima [UNIFESP; Fernandes-Santos, Luciano [UNIFESP; Oliveira, Larissa C. [UNIFESP; Longo, Beatriz Monteiro [UNIFESP; Andersen, Monica Levy [UNIFESP; Tufik, Sergio [UNIFESP; Frussa-Filho, Roberto [UNIFESP

    2013-01-01

    Caffeine is the most widely used psychoactive substance in the world and it is generally believed that it promotes beneficial effects on cognitive performance. However, there is also evidence suggesting that caffeine has inhibitory effects on learning and memory. Considering that caffeine may have anxiogenic effects, thus changing the emotional state of the subjects, state-dependent learning may play a role in caffeine-induced cognitive alterations. Mice were administered 20 mg/kg caffeine be...

  9. Examining Neuronal Connectivity and Its Role in Learning and Memory

    Science.gov (United States)

    Gala, Rohan

    Learning and long-term memory formation are accompanied with changes in the patterns and weights of synaptic connections in the underlying neuronal network. However, the fundamental rules that drive connectivity changes, and the precise structure-function relationships within neuronal networks remain elusive. Technological improvements over the last few decades have enabled the observation of large but specific subsets of neurons and their connections in unprecedented detail. Devising robust and automated computational methods is critical to distill information from ever-increasing volumes of raw experimental data. Moreover, statistical models and theoretical frameworks are required to interpret the data and assemble evidence into understanding of brain function. In this thesis, I first describe computational methods to reconstruct connectivity based on light microscopy imaging experiments. Next, I use these methods to quantify structural changes in connectivity based on in vivo time-lapse imaging experiments. Finally, I present a theoretical model of associative learning that can explain many stereotypical features of experimentally observed connectivity.

  10. Safety learning among young newly employed in three trades – the role of the profession?

    DEFF Research Database (Denmark)

    Grytnes, Regine; Dyreborg, Johnny; Jørgensen, Astrid

    2017-01-01

    Background Young workers aged 18-24 years have an increased risk of injuries at work compared to older workers. This is a problem not only for young workers themselves but also for the society and it lends relevance to the question of how young people learn safe working practices. Safety learning...... to be 'something everyone can do'. Learning safe working practices are shown to be part of canonical and non- canonical professional norms and safety learning is thus an integral part of local and professional induction practices....... is not achieved through information and campaigns alone; it also involves practical training and mentorship at the specific work place. In this paper an analysis of how induction practices relates to safety learning in three different trades is pursued focusing especially on the role of the professions...

  11. ASPECTS REGARDING THE ROLE OF FACILITATORS IN CREATIVE LEARNING AND INNOVATIVE TEACHING

    Directory of Open Access Journals (Sweden)

    TODORUȚ AMALIA VENERA

    2017-12-01

    Full Text Available In this paper I have analysed a series of facilitators that determine creativity and innovation in teaching learning processes, emphasising the role of assessment, organizational culture and information technologies as relevant and essential elements within this challenging approach to create the conditions for an intelligent development of the educational processes. Also I approached issues related to creative learning and innovative teaching in a society in which knowledge takes more and more intense forms and, they require changes and deep transformations in all educational environments. The fundamental objective was to underline the need to learn creatively and to teach innovatively, given the conditions of the development of information technologies and a deeper and deeper immersion in this information environment, with effects on involving more effectively the students in their own learning approach. Based on scientific researches, observation and comparative analyzes, I identified the facilitators which, along with the technologies, support the creative learning and innovative teaching.

  12. The Role of Open and Distance Learning in Promoting Professional ...

    African Journals Online (AJOL)

    This paper unveils the unique role played by ODL in promoting professional training and development in Tanzania. ODL is significantly increasing in its importance in most societies if not all; this is justified by the increasing in enrolment in ODL institutions. In order to cope with the demanding world, individuals need to ...

  13. Context Based Learning: A Role for Cinema in Science Education

    Science.gov (United States)

    Arroio, Agnaldo

    2010-01-01

    This paper discusses the role of cinema as a tool for science education. Based on the socio-cultural approach put forward by Vygotsky, it draws attention to the fact that an audience can interact with the characters and share their emotions and actions showed in an audiovisual setting. Experiences come from an interaction with a learning…

  14. The Role of the Virtual Microscope in Distance Learning

    Science.gov (United States)

    Whalley, Peter; Kelley, Simon; Tindle, Andrew

    2011-01-01

    Screen-based microscopes allow for a shared visualisation and task-directed conversations that offer significant pedagogic advantages for the science disciplines involving observation of natural samples such as the geosciences and biosciences, and particularly for distance education in these disciplines. The role and development of a virtual…

  15. Acrolein coupling on reduced TiO 2(1 1 0): The effect of surface oxidation and the role of subsurface defects

    Science.gov (United States)

    Benz, Lauren; Haubrich, Jan; Quiller, Ryan G.; Friend, Cynthia M.

    2009-04-01

    Reactions of acrolein, water, and oxygen with the vacuum-reduced surface of TiO 2(1 1 0) are reported in a temperature programmed reaction study of the interaction of an aldehydic pollutant with a reducible metal oxide. A total of 25% of the acrolein that binds to the surface is converted to products. Notably, carbon-carbon coupling occurs with 86% selectivity for formation of C 6 products: C 6H 8, identified as 1,3-cyclohexadiene, in a peak at 500 K and benzene immediately thereafter at 530 K. Acrolein is evolved from the surface in three peaks: a peak independent of coverage at 495 K, attributed to decomposition of an intermediate that is partly converted to C 6H 8; a coverage-dependent peak that shifts from 370 K (low coverage) to 260 K (high coverage), which is attributed to adsorption at 5-fold coordinated Ti sites; and a multilayer state at 160 K. Water and acrolein compete for 5-fold coordinated titanium sites when dosed sequentially. The addition of water also opens a new reaction pathway, leading to the hydrogenation of acrolein to form propanal. Water has no effect on the yield of 1,3-cyclohexadiene. Exposure of the surface to oxygen prior to acrolein dosing quenches the evolution of acrolein at 495 K and concurrently eliminates the coupling. From these results, we propose that reduced subsurface defects such as titanium ion interstitials play a role in the reactions observed here. The notion that subsurface defects may contribute to the reactivity of organic molecules over reducible oxide substrates may prove to be general.

  16. Evolution of a major drug metabolizing enzyme defect in the domestic cat and other felidae: phylogenetic timing and the role of hypercarnivory.

    Directory of Open Access Journals (Sweden)

    Binu Shrestha

    2011-03-01

    Full Text Available The domestic cat (Felis catus shows remarkable sensitivity to the adverse effects of phenolic drugs, including acetaminophen and aspirin, as well as structurally-related toxicants found in the diet and environment. This idiosyncrasy results from pseudogenization of the gene encoding UDP-glucuronosyltransferase (UGT 1A6, the major species-conserved phenol detoxification enzyme. Here, we established the phylogenetic timing of disruptive UGT1A6 mutations and explored the hypothesis that gene inactivation in cats was enabled by minimal exposure to plant-derived toxicants. Fixation of the UGT1A6 pseudogene was estimated to have occurred between 35 and 11 million years ago with all extant Felidae having dysfunctional UGT1A6. Out of 22 additional taxa sampled, representative of most Carnivora families, only brown hyena (Parahyaena brunnea and northern elephant seal (Mirounga angustirostris showed inactivating UGT1A6 mutations. A comprehensive literature review of the natural diet of the sampled taxa indicated that all species with defective UGT1A6 were hypercarnivores (>70% dietary animal matter. Furthermore those species with UGT1A6 defects showed evidence for reduced amino acid constraint (increased dN/dS ratios approaching the neutral selection value of 1.0 as compared with species with intact UGT1A6. In contrast, there was no evidence for reduced amino acid constraint for these same species within UGT1A1, the gene encoding the enzyme responsible for detoxification of endogenously generated bilirubin. Our results provide the first evidence suggesting that diet may have played a permissive role in the devolution of a mammalian drug metabolizing enzyme. Further work is needed to establish whether these preliminary findings can be generalized to all Carnivora.

  17. The roles of knitted mesh-reinforced collagen-chitosan hybrid scaffold in the one-step repair of full-thickness skin defects in rats.

    Science.gov (United States)

    Wang, Xingang; You, Chuangang; Hu, Xinlei; Zheng, Yurong; Li, Qiyin; Feng, Zhanzeng; Sun, Huafeng; Gao, Changyou; Han, Chunmao

    2013-08-01

    Full-thickness skin defects represent a significant and urgent clinical problem. Dermal substitutes serving as a regenerative template to induce dermal reconstruction provide a promising method to treat serious skin defects. Although collagen-chitosan dermal scaffolds display good biocompatibility and a suitable porous structure for angiogenesis and tissue regeneration, their poor mechanical properties compromise their application. To develop a well-supported dermal substitute, a poly(l-lactide-co-glycolide) (PLGA) knitted mesh was fabricated and integrated with collagen-chitosan scaffold (CCS) to obtain a PLGA knitted mesh-reinforced CCS (PLGAm/CCS). The morphology of this PLGAm/CCS was investigated in vitro. To characterize the tissue response, specifically angiogenesis and tissue regeneration, the PLGAm/CCS was transplanted in combination with thin split-thickness autografts to repair full-thickness skin wounds using a one-step surgical procedure in Sprague-Dawley rats. These results were then compared with CCSs. At weeks 2, 4 and 8 after the operation, the healing wounds were imaged to analyse wound changes, and tissue specimens were harvested for histology, immunohistochemistry, real-time quantitative polymerase chain reaction and Western blot analysis. The results demonstrated that collagen-chitosan sponge in the PLGAm/CCS remained porous, interconnected and occupied the openings of PLGA mesh, and the incorporation of the PLGA knitted mesh into CCS improved the mechanical strength with little influence on its mean pore size and porosity. Following transplantation, PLGAm/CCS inhibited wound contraction, and effectively promoted neotissue formation and blood vessel ingrowth. In conclusion, the mechanical strength of the scaffolds plays an important role in the process of tissue regeneration and vascularization. The ability of PLGAm/CCS to promote angiogenesis and induce in situ tissue regeneration demonstrates its potential in skin tissue engineering. Copyright

  18. Embedded defects

    International Nuclear Information System (INIS)

    Barriola, M.; Vachaspati, T.; Bucher, M.

    1994-01-01

    We give a prescription for embedding classical solutions and, in particular, topological defects in field theories which are invariant under symmetry groups that are not necessarily simple. After providing examples of embedded defects in field theories based on simple groups, we consider the electroweak model and show that it contains the Z string and a one-parameter family of strings called the W(α) string. It is argued that although the members of this family are gauge equivalent when considered in isolation, each member becomes physically distinct when multistring configurations are considered. We then turn to the issue of stability of embedded defects and demonstrate the instability of a large class of such solutions in the absence of bound states or condensates. The Z string is shown to be unstable for all values of the Higgs boson mass when θ W =π/4. W strings are also shown to be unstable for a large range of parameters. Embedded monopoles suffer from the Brandt-Neri-Coleman instability. Finally, we connect the electroweak string solutions to the sphaleron

  19. The Role of Interactive E-Learning in Problem-Solving Skill and Independent Learning of Medical Students in Psychology Courses

    OpenAIRE

    Sahar Mohamadi; Sayedeh Maryam Hosseiny; Sayedeh Sana Hosseiny

    2016-01-01

    Introduction: Today, due to the speed and amount of science production in the world, knowledge processing and learning is changing. In this regard, independent learning using new instructional methods interactively with a specific goal in order to dominate the content and assignments with self-regulation strategies is of great importance. This study is aimed to evaluate interactive e-learning role on medical students’ learning in psychology courses. Methods: This study is a experimental r...

  20. Creating a Role for Embedded Librarians Within an Active Learning Environment.

    Science.gov (United States)

    Hackman, Dawn E; Francis, Marcia J; Johnson, Erika; Nickum, Annie; Thormodson, Kelly

    2017-01-01

    In 2013, the librarians at a small academic health sciences library reevaluated their mission, vision, and strategic plan to expand their roles. The school was transitioning to a new pedagogical culture and a new building designed to emphasize interprofessional education and active learning methodologies. Subsequent efforts to implement the new strategic plan resulted in the librarians joining curriculum committees and other institutional initiatives, such as an Active Learning Task Force, and participating in faculty development workshops. This participation has increased visibility and led to new roles and opportunities for librarians.

  1. Senior veterinary students' perceptions of using role play to learn communication skills.

    Science.gov (United States)

    Brandt, Jennifer C; Bateman, Shane W

    2006-01-01

    Recent studies of veterinary practice have suggested a correlation between well-developed communication skills and job satisfaction, career retention, customer satisfaction, decreased lawsuits, and financial remuneration for veterinarians. Veterinary educators are under growing pressure to teach functional communication skills to veterinary students; however, the methods employed have not been well evaluated. In this study we have evaluated veterinary student's attitudes to learning communication skills by participating in role play. The study indicates that experiential learning modalities such as role play are perceived as effective by students, despite reluctance to participate and some discomfort surrounding participation.

  2. Transformative Learning: The Role of Research in Traditional Clinical Disciplines

    Science.gov (United States)

    Tims, Michael

    2014-01-01

    One of an educator’s main tasks is to develop the intellectual openness of students that is necessary for transformative learning to take place. An initial step in removing the constraint of assumption is to employ the process of unlearning in the classroom. Unlearning in its simplest form can be described as the process through which the student learns to ask questions about a subject on which they are passionate, and through critical reflection, to construct and validate a new understanding based on observations and information generated by the original questions. Developing the ability to improvise and innovate are clear and positive indications that unlearning has occurred, and the Maryland University of Integrative Health’s (MUIH’s) educators have found that integrating research methods into class and group projects can accelerate the unlearning process. MUIH promotes students’ effort to solve interesting problems using the community found within the classroom. The natural state of relativism found in group processes lends itself to making explicit the assumptions each individual brings to the process. MUIH’s methods include engaging students in visual deconstruction of research data found in graphs, tables, and images; having students identify the end point of a line of inquiry; and evaluating a previously accumulated body of evidence to determine if it supports a product’s claims (eg, claims about general health, structure-function, or therapeutic value). The ultimate aim in asking students to take part in research embedded in coursework is to provide an assessment of their abilities that is more closely linked to discipline-specific experience. MUIH’s method of ingraining a culture of inquiry into both classroom and independent research serves to enhance students’ self-awareness about the constraints of their own a priori thinking and to nurture a deeper trust in their own informed intuition. PMID:26770105

  3. Role of classical conditioning in learning gastrointestinal symptoms.

    Science.gov (United States)

    Stockhorst, Ursula; Enck, Paul; Klosterhalfen, Sibylle

    2007-07-07

    Nausea and/or vomiting are aversive gastrointestinal (GI) symptoms. Nausea and vomiting manifest unconditionally after a nauseogenic experience. However, there is correlative, quasiexperimental and experimental evidence that nausea and vomiting can also be learned via classical (Pavlovian) conditioning and might occur in anticipation of the nauseogenic event. Classical conditioning of nausea can develop with chemotherapy in cancer patients. Initially, nausea and vomiting occur during and after the administration of cytotoxic drugs (post-treatment nausea and vomiting) as unconditioned responses (UR). In addition, 20%-30% of cancer patients receiving chemotherapy report these side effects, despite antiemetic medication, when being re-exposed to the stimuli that usually signal the chemotherapy session and its drug infusion. These symptoms are called anticipatory nausea (AN) and/or anticipatory vomiting (ANV) and are explained by classical conditioning. Moreover, there is recent evidence for the assumption that post-chemotherapy nausea is at least partly influenced by learning. After summarizing the relevant assumptions of the conditioning model, revealing that a context can become a conditioned stimulus (CS), the present paper summarizes data that nausea and/or vomiting is acquired by classical conditioning and, consequently, may be alleviated by conditioning techniques. Our own research has focussed on two aspects and is emphasized here. First, a conditioned nausea model was established in healthy humans using body rotation as the nausea-inducing treatment. The validity of this motion-sickness model to examine conditioning mechanisms in the acquisition and alleviation of conditioned nausea and associated endocrine and immunological responses is summarized. Results from the rotation-induced motion sickness model showed that gender is an important moderator variable to be considered in further studies. This paper concludes with a review of the application of the

  4. The Physiology of Fear: Reconceptualizing the Role of the Central Amygdala in Fear Learning

    Science.gov (United States)

    Keifer, Orion P.; Hurt, Robert C.; Ressler, Kerry J.

    2015-01-01

    The historically understood role of the central amygdala (CeA) in fear learning is to serve as a passive output station for processing and plasticity that occurs elsewhere in the brain. However, recent research has suggested that the CeA may play a more dynamic role in fear learning. In particular, there is growing evidence that the CeA is a site of plasticity and memory formation, and that its activity is subject to tight regulation. The following review examines the evidence for these three main roles of the CeA as they relate to fear learning. The classical role of the CeA as a routing station to fear effector brain structures like the periaqueductal gray, the lateral hypothalamus, and paraventricular nucleus of the hypothalamus will be briefly reviewed, but specific emphasis is placed on recent literature suggesting that the CeA 1) has an important role in the plasticity underlying fear learning, 2) is involved in regulation of other amygdala subnuclei, and 3) is itself regulated by intra- and extra-amygdalar input. Finally, we discuss the parallels of human and mouse CeA involvement in fear disorders and fear conditioning, respectively. PMID:26328883

  5. The Library's role and challenges in implementing an e-learning strategy: a case study from northern Australia.

    Science.gov (United States)

    Ritchie, Ann

    2011-03-01

      The Northern Territory Department of Health and Families' (DHF) Library supports education programs for all staff. DHF is implementing an e-learning strategy, which may be viewed as a vehicle for coordinating the education function throughout the organisation.   The objective of this study is to explore the concept of e-learning in relation to the Library's role in implementing an organisation-wide e-learning strategy.   The main findings of a literature search about the effectiveness of e-learning in health professionals' education, and the responsibility and roles of health librarians in e-learning are described. A case study approach is used to outline the current role and future opportunities and challenges for the Library.   The case study presents the organisation's strategic planning context. Four areas of operational activity which build on the Library's current educational activities are suggested: the integration of library resources 'learning objects' within a Learning Management System; developing online health information literacy training programs; establishing a physical and virtual 'e-Learning Library/Centre'; developing collaborative partnerships, taking on new responsibilities in e-learning development, and creating a new e-learning librarian role.   The study shows that the Library's role is fundamental to developing the organisation's e-learning capacity and implementing an organisation-wide e-learning strategy. © 2010 The authors. Health Information and Libraries Journal © 2010 Health Libraries Group.

  6. Improving health care quality and safety: the role of collective learning

    Directory of Open Access Journals (Sweden)

    Singer SJ

    2015-11-01

    Full Text Available Sara J Singer,1–4 Justin K Benzer,4–6 Sami U Hamdan4,6 1Department of Health Policy and Management, Harvard T.H. Chan School of Public Health, Boston, MA, USA; 2Department of Medicine, Harvard Medical School, Boston, MA, USA; 3Mongan Institute for Health Policy, Massachusetts General Hospital, Boston, MA, USA; 4Center for Healthcare Organization and Implementation Research, VA Boston Healthcare System, Boston, MA, USA; 5VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX, USA; 6Department of Health Policy and Management, Boston University School of Public Health, Boston, MA, USA Abstract: Despite decades of effort to improve quality and safety in health care, this goal feels increasingly elusive. Successful examples of improvement are infrequently replicated. This scoping review synthesizes 76 empirical or conceptual studies (out of 1208 originally screened addressing learning in quality or safety improvement, that were published in selected health care and management journals between January 2000 and December 2014 to deepen understanding of the role that collective learning plays in quality and safety improvement. We categorize learning activities using a theoretical model that shows how leadership and environmental factors support collective learning processes and practices, and in turn team and organizational improvement outcomes. By focusing on quality and safety improvement, our review elaborates the premise of learning theory that leadership, environment, and processes combine to create conditions that promote learning. Specifically, we found that learning for quality and safety improvement includes experimentation (including deliberate experimentation, improvisation, learning from failures, exploration, and exploitation, internal and external knowledge acquisition, performance monitoring and comparison, and training. Supportive learning environments are characterized by team characteristics like psychological

  7. Immunomodulatory role of interleukin-10 in visceral leishmaniasis: defective activation of protein kinase C-mediated signal transduction events.

    Science.gov (United States)

    Bhattacharyya, S; Ghosh, S; Jhonson, P L; Bhattacharya, S K; Majumdar, S

    2001-03-01

    Leishmania donovani, an intracellular protozoan parasite, challenges host defense mechanisms by impairing the signal transduction of macrophages. In this study we investigated whether interleukin-10 (IL-10)-mediated alteration of signaling events in a murine model of visceral leishmaniasis is associated with macrophage deactivation. Primary in vitro cultures of macrophages infected with leishmanial parasites markedly elevated the endogenous release of IL-10. Treatment with either L. donovani or recombinant IL-10 (rIL-10) inhibited both the activity and expression of the Ca2+-dependent protein kinase C (PKC) isoform. However, preincubation with neutralizing anti-IL-10 monoclonal antibody (MAb) restored the PKC activity in the parasitized macrophage. Furthermore, we observed that coincubation of macrophages with rIL-10 and L. donovani increased the intracellular parasite burden, which was abrogated by anti-IL-10 MAb. Consistent with these observations, generation of superoxide (O2-) and nitric oxide and the release of murine tumor necrosis factor-alpha were attenuated in response to L. donovani or rIL-10 treatment. On the other hand, preincubation of the infected macrophages with neutralizing anti-IL-10 MAb significantly blocked the inhibition of nitric oxide and murine tumor necrosis factor-alpha release by the infected macrophages. These findings imply that infection with L. donovani induces endogenous secretion of murine IL-10, which in turn facilitates the intracellular survival of the protozoan and orchestrates several immunomodulatory roles via selective impairment of PKC-mediated signal transduction.

  8. Investigations on the role of alkali to obtain modulated defect concentrations for Cu{sub 2}O thin films

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Anirban, E-mail: anirban.chowdhury@gmail.com [Research and Development, Tata Steel Limited, Jamshedpur, 831001 (India); Bijalwan, Pavan Kumar [Research and Development, Tata Steel Limited, Jamshedpur, 831001 (India); Sahu, Ranjan Kumar [MST Division, CSIR-National Metallurgical Laboratory, Jamshedpur, 831007 (India)

    2014-01-15

    An economic successive ionic layer adsorption and reaction (SILAR) method has been investigated for depositing thin Cu{sub 2}O layers on steel. The mole ratios of the Cu{sup +} ions to OH{sup −} ions in the alkali bath were varied and the changes in the properties were characterised by X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and Ultraviolet–visible spectroscopy techniques. The increase in the binding energy values of the Cu 2p peaks in XPS established that an optimum copper vacancy concentration can be obtained for a Cu{sup +}/OH{sup −} mole ratio between 1:10 and 1:15; SEM studies confirmed a dense, uniform microstructure for Cu{sub 2}O thin films coated with these compositions. The strongest absolute peak intensity counts in PL for the peak at 580 nm along with low energy peaks (1.2–1.4 eV) due to Cu vacancy was found to be most prominent for thin film made with Cu{sup +}/OH{sup −} mole ratio 1:15. The role of alkali concentration has been explained in relation to create a stable Cu{sub 2−δ}O structure with optimum copper vacancy. This is an easy way to modulate surface reactivity of the Cu{sub 2}O thin layers and the concept can be utilised for large area device integrations for various electrical and mechanical applications.

  9. Vacancy-related defect distributions in 11B-, 14N-, and 27Al-implanted 4H-SiC: Role of channeling

    International Nuclear Information System (INIS)

    Janson, M.S.; Slotte, J.; Kuznetsov, A.Yu.; Saarinen, K.; Hallen, A.

    2004-01-01

    The defect distributions in 11 B-, 14 N-, and 27 Al-implanted epitaxial 4H-SiC are studied using monoenergetic positron beams. At least three types of defects are needed to account for the Doppler broadening annihilation spectra and two of the defects are tentatively identified as V Si , and V Si V C . By comparing the defect profiles extracted from the annihilation spectra to the chemical profiles determined by secondary ion mass spectrometry, and to the primary defect profiles obtained from binary collision approximation simulations, it is concluded that the defects found at depths considerably deeper than the projected range of the implanted ions mainly originate from deeply channeled ions

  10. Adult sibling experience, roles, relationships and future concerns - a review of the literature in learning disabilities.

    Science.gov (United States)

    Davys, Deborah; Mitchell, Duncan; Haigh, Carol

    2011-10-01

    This paper provides a review of the literature related to adult siblings of learning-disabled people. Siblings of learning-disabled people are often looked upon as next of kin when older parents die; however, there is little research regarding sibling views and wishes. A literature review of published peer-reviewed empirical research was undertaken. Electronic databases and citation tracking were used to collate data using key terms such as adult siblings and learning disability. Relevant articles were analysed, compared and contrasted. Six key themes emerged suggesting a varied impact of learning disability upon sibling lives in areas that include life choices, relationships, identity and future plans. Some siblings report a positive impact upon life, others state their lives are comparable with other adults who do not have a learning-disabled sibling and others still report a negative impact. Sibling roles and relationships are varied. Evidence suggests that sibling roles, relationships and experience are affected by life stage. Parents often have a primary care role for the disabled person, whilst siblings perform a more distant role; however, sibling involvement often rises when parents are no longer able to provide previous levels of support. Many factors appear to affect the sibling experience and uptake of roles including gender, life stage and circumstances, level of disability, health status and relationships between family members. Siblings are concerned about the future, particularly when parents are no longer able to provide support, and many appear to have expectations of future responsibilities regarding their disabled sibling. As siblings of people who have a learning disability are often expected by society to provide support, it is important that health and social care practitioners are aware of issues that may impact on this relationship. © 2011 Blackwell Publishing Ltd.

  11. Visual Literacy and Biochemistry Learning: The role of external representations

    Directory of Open Access Journals (Sweden)

    V.J.S.V. Santos

    2011-04-01

    Full Text Available Visual Literacy can bedefined as people’s ability to understand, use, think, learn and express themselves through external representations (ER in a given subject. This research aims to investigate the development of abilities of ERs reading and interpretation by students from a Biochemistry graduate course of theFederal University of São João Del-Rei. In this way, Visual Literacy level was  assessed using a questionnaire validatedin a previous educational research. This diagnosis questionnaire was elaborated according to six visual abilitiesidentified as essential for the study of the metabolic pathways. The initial statistical analysis of data collectedin this study was carried out using ANOVA method. Results obtained showed that the questionnaire used is adequate for the research and indicated that the level of Visual Literacy related to the metabolic processes increased significantly with the progress of the students in the graduation course. There was also an indication of a possible interference in the student’s performancedetermined by the cutoff punctuation in the university selection process.

  12. The Role of Electronic Learning Technology in Networks Systems

    International Nuclear Information System (INIS)

    Abd ELhamid, A.; Ayad, N.M.A.; Fouad, Y.; Abdelkader, T.

    2016-01-01

    Recently, Electronic Learning Technology (ELT) has been widely spread as one of the new technologies in the world through using Information and Communication Technology (ICT). One of the strategies of ELT is Simulation, for instance Military and Medical simulations that are used to avoid risks and reduce Costs. A wireless communication network refers to any network not physically connected by cables, which enables the desired convenience and mobility for the user. Wireless communication networks have been useful in areas such as commerce, education and defense. According to the nature of a particular application, they can be used in home-based and industrial systems or in commercial and military environments. Historically, Mobile Ad-hoc Networks (MANET) have primarily been used for tactical military network related applications to improve battlefield communications/ survivability. MANET is a collection of wireless nodes that can dynamically be set up anywhere and anytime without using any pre-existing network infrastructure. Mobility in wireless networks basically refers to nodes changing its point of attachment to the network. Also, how the end terminals can move, there are many mobility models described the movement of nodes, many researchers use the Random Way point Mobility Model (RWPM). In this paper, a Graphical User Interface (GUI) for RWPM simulation is introduced as a proposal to be used through ELT Project. In the research area of computer and communications networks, simulation is a very useful technique for the behavior of networks

  13. The Role of Learning- and Presentation- Portfolios in Design Educations

    DEFF Research Database (Denmark)

    Thomsen, Bente Dahl; Ovesen, Nis

    2014-01-01

    Students that primarily study design through team-based projects often struggle to develop presentation portfolios that differentiate from the ones of other students. In the industry, design managers experience this as a problem, as they often receive job applications with presentation portfolios...... resources from other activities, which is why the templates have to be carefully balanced in order to achieve the desired effect. The portfolio method proved to be especially good at illustrating process related competencies.......Students that primarily study design through team-based projects often struggle to develop presentation portfolios that differentiate from the ones of other students. In the industry, design managers experience this as a problem, as they often receive job applications with presentation portfolios...... of the portfolio method in engineering design educations, this research project has investigated the method as part of a course programme. The preliminary experiments and results show that learning portfolio templates are effective in strengthening certain activities. On the other hand, the method risks draining...

  14. Examining Organizational Learning in Schools: The Role of Psychological Safety, Experimentation, and Leadership that Reinforces Learning

    Science.gov (United States)

    Higgins, Monica; Ishimaru, Ann; Holcombe, Rebecca; Fowler, Amy

    2012-01-01

    This study draws upon theory and methods from the field of organizational behavior to examine organizational learning (OL) in the context of a large urban US school district. We build upon prior literature on OL from the field of organizational behavior to introduce and validate three subscales that assess key dimensions of organizational learning…

  15. Learning Computerese: The Role of Second Language Learning Aptitude in Technology Acceptance

    Science.gov (United States)

    Warner, Janis A.; Koufteros, Xenophon; Verghese, Anto

    2014-01-01

    This article introduces a new construct coined as Computer User Learning Aptitude (CULA). To establish construct validity, CULA is embedded in a nomological network that extends the technology acceptance model (TAM). Specifically, CULA is posited to affect perceived usefulness and perceived ease of use, the two underlying TAM constructs.…

  16. The role of peer assisted learning to improve the effectivity of clinical skill laboratory learning in dental education

    Directory of Open Access Journals (Sweden)

    Agus Ardinansyah

    2016-06-01

    Full Text Available Nowadays, the clinical skill learning in dental education has begun in pre-clinic, known as Clinical Skill Laboratory (CSL which needs human resources, many and expensive tools and manikins, and enough times for practise. One of the method used in CSL in dental education is PeerAssisted Learning (PAL defined as “the development of knowledge and skill through active help and support among status equals or match companions”. This paper aims is to explain the role of PAL method to improve the effectivity of CSL learning in dental education in preclinical stage. Reviewing on the relevant literatures regarding peer assisted learning on the implementation of the clinical skill laboratory in dental education. The effectivity of CSL learning needs close supervision and individual feedback, so enough tutors is important through the process. This PAL method considered to be helpfull with the increasing numbers of dental students and the limitation of staff faculty. This method is found feasible, well accepted by peer-tutors and students, and can be as effective as conventional learning method. This is also useful for peer-teacher because they more intrinsically motivated, have higher conceptual learning scores, and perceive themselves to be more actively engaged with the environment than students who learn in order to be tested.  However, there are several limitation of this method. The contact time between students and medical doctors may decrease significantlyand it does not seem to be generally qualified to transfer such complex procedures.It also needs peer-teachers training and a detailed manual. Questions concerning the cost-effectiveness and profitability of student tutor-guided technical skills training may thus arise. But one institution that implemented this method states that the majority of their tutors decided to continue their teaching activity in the skills lab and that these experienced tutors, in addition to established faculty staff

  17. Crossing the Cartesian Divide: An Investigation into the Role of Emotion in Science Learning

    Science.gov (United States)

    Staus, Nancy L.

    Although many science educators and researchers believe that emotion is an important part of the learning process, few researchers have dealt with the topic in a systematic fashion. The purpose of this study was to examine the role of emotion in the learning process, particularly in the learning of science content. My study utilized a dimensional perspective which defined emotion in terms of arousal and valence, and drew on research from the fields of psychology and neuroscience to examine how emotion affects different aspects of cognition such as attention and memory. On the basis of these findings, I developed and tested a path model to investigate the predicted relationships among emotional arousal, valence, attention, intrinsic motivation and short- and long-term learning outcomes. I conducted the study in two phases. The first phase took place in a psychology laboratory in which participants watched either an exciting or neutral nature video, read a factual article related to the video and were tested on their learning. The second phase took place at the Oregon Coast Aquarium in which participants watched a narrated otter or sea lion presentation and took a short posttest after the show. In both phases, participants' emotional arousal, valence, attention, and motivation levels were also measured for inclusion in the model. The results indicated that emotional arousal was an important predictor of short-term learning in both experiments although its effect was fully mediated by attention at the aquarium. In addition, negative valence (displeasure) and intrinsic motivation were strong predictors of short-term learning in the laboratory experiment. At the aquarium, the narrator of the animal presentation strongly affected both attention and short-term learning---visitors who listened to a non-scripted rather than a scripted narration paid more attention and had significantly better short-term learning outcomes. In the aquarium study, emotional arousal correlated

  18. The role of alpha-rhythm states in perceptual learning: insights from experiments and computational models

    Science.gov (United States)

    Sigala, Rodrigo; Haufe, Sebastian; Roy, Dipanjan; Dinse, Hubert R.; Ritter, Petra

    2014-01-01

    During the past two decades growing evidence indicates that brain oscillations in the alpha band (~10 Hz) not only reflect an “idle” state of cortical activity, but also take a more active role in the generation of complex cognitive functions. A recent study shows that more than 60% of the observed inter-subject variability in perceptual learning can be ascribed to ongoing alpha activity. This evidence indicates a significant role of alpha oscillations for perceptual learning and hence motivates to explore the potential underlying mechanisms. Hence, it is the purpose of this review to highlight existent evidence that ascribes intrinsic alpha oscillations a role in shaping our ability to learn. In the review, we disentangle the alpha rhythm into different neural signatures that control information processing within individual functional building blocks of perceptual learning. We further highlight computational studies that shed light on potential mechanisms regarding how alpha oscillations may modulate information transfer and connectivity changes relevant for learning. To enable testing of those model based hypotheses, we emphasize the need for multidisciplinary approaches combining assessment of behavior and multi-scale neuronal activity, active modulation of ongoing brain states and computational modeling to reveal the mathematical principles of the complex neuronal interactions. In particular we highlight the relevance of multi-scale modeling frameworks such as the one currently being developed by “The Virtual Brain” project. PMID:24772077

  19. Teaching psychosomatic medicine using problem-based learning and role-playing.

    Science.gov (United States)

    Heru, Alison M

    2011-01-01

    Problem-based learning (PBL) has been implemented in medical education world-wide. Despite its popularity, it has not been generally considered useful for residency programs. The author presents a model for the implementation of PBL in residency programs. The author presents a description of a PBL curriculum for teaching psychosomatic medicine to PGY 2 members in a psychiatry training program. The goals of PBL are to encourage self-directed learning; enhance curiosity, using case-based, contextualized learning; promote collaborative practice; and support patient-centered care. The addition of role-playing exercises helps PGY 2 residents to develop their skills from simply developing a differential diagnosis to being able to construct biopsychosocial formulations, and it provides these residents an opportunity to practice presenting case formulations to the patient and family. Residents and faculty enjoyed the PBL role-playing sessions. Residents wanted the learning objectives given to them rather than generating their own learning objectives, to move through the cases faster, and to receive more information and more cases. Teaching psychosomatic medicine, using PBL and role-playing, allows many of the proposed Academy of Psychosomatic Medicine residency core competencies to be met. However, further refinement of the PBL method needs to take place in order to adapt its use to residency programs.

  20. Distinct roles of the RasGAP family proteins in C. elegans associative learning and memory.

    Science.gov (United States)

    Gyurkó, M Dávid; Csermely, Péter; Sőti, Csaba; Steták, Attila

    2015-10-15

    The Ras GTPase activating proteins (RasGAPs) are regulators of the conserved Ras/MAPK pathway. Various roles of some of the RasGAPs in learning and memory have been reported in different model systems, yet, there is no comprehensive study to characterize all gap genes in any organism. Here, using reverse genetics and neurobehavioural tests, we studied the role of all known genes of the rasgap family in C. elegans in associative learning and memory. We demonstrated that their proteins are implicated in different parts of the learning and memory processes. We show that gap-1 contribute redundantly with gap-3 to the chemosensation of volatile compounds, gap-1 plays a major role in associative learning, while gap-2 and gap-3 are predominantly required for short- and long-term associative memory. Our results also suggest that the C. elegans Ras orthologue let-60 is involved in multiple processes during learning and memory. Thus, we show that the different classes of RasGAP proteins are all involved in cognitive function and their complex interplay ensures the proper formation and storage of novel information in C. elegans.

  1. The role of alpha-rhythm states in perceptual learning: insights from experiments and computational models

    Directory of Open Access Journals (Sweden)

    Rodrigo eSigala

    2014-04-01

    Full Text Available During the past two decades growing evidence indicates that brain oscillations in the alpha band (~10 Hz not only reflect an ‘idle’ state of cortical activity, but also take a more active role in the generation of complex cognitive functions. A recent study shows that more than 60% of the observed inter-subject variability in perceptual learning can be ascribed to ongoing alpha activity. This evidence indicates a significant role of alpha oscillations for perceptual learning and hence motivates to explore the potential underlying mechanisms. Hence, it is the purpose of this review to highlight existent evidence that ascribes intrinsic alpha oscillations a role in shaping our ability to learn. In the review, we disentangle the alpha rhythm into different neural signatures that control information processing within individual functional building blocks of perceptual learning. We further highlight computational studies that shed light on potential mechanisms regarding how alpha oscillations may modulate information transfer and connectivity changes relevant for learning. To enable testing of those model based hypotheses, we emphasize the need for multidisciplinary approaches combining assessment of behavior and multi-scale neuronal activity, active modulation of ongoing brain states and computational modeling to reveal the mathematical principles of the complex neuronal interactions. In particular we highlight the relevance of multi-scale modeling frameworks such as the one currently being developed by The Virtual Brain project.

  2. Contrasting role of octopamine in appetitive and aversive learning in the crab Chasmagnathus.

    Directory of Open Access Journals (Sweden)

    Laura Kaczer

    Full Text Available BACKGROUND: Biogenic amines are implicated in reinforcing associative learning. Octopamine (OA is considered the invertebrate counterpart of noradrenaline and several studies in insects converge on the idea that OA mediates the reward in appetitive conditioning. However, it is possible to assume that OA could have a different role in an aversive conditioning. METHODOLOGY/PRINCIPAL FINDINGS: Here we pharmacologically studied the participation of OA in two learning processes in the crab Chasmagnathus granulatus, one appetitive and one aversive. It is shown that the aversive memory is impaired by an OA injection applied immediately or 30 minutes after the last training trial. By contrast, the appetitive memory is blocked by OA antagonists epinastine and mianserine, but enhanced by OA when injected together with the supply of a minimum amount of reinforcement. Finally, double-learning experiments in which crabs are given the aversive and the appetitive learning either successively or simultaneously allow us to study the interaction between both types of learning and analyze the presumed action of OA. We found that the appetitive training offered immediately, but not one hour, after an aversive training has an amnesic effect on the aversive memory, mimicking the effect and the kinetic of an OA injection. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that the role of OA is divergent in two memory processes of opposite signs: on the one hand it would mediate the reinforcement in appetitive learning, and on the other hand it has a deleterious effect over aversive memory consolidation.

  3. If Your Child Has a Heart Defect (For Parents)

    Science.gov (United States)

    ... Videos for Educators Search English Español If Your Child Has a Heart Defect KidsHealth / For Parents / If ... has any of these symptoms. Caring for Your Child Parenting kids with heart defects includes learning about ...

  4. EMPOWERING THE HUMAN RESOURCES AND THE ROLE OF DISTANCE LEARNING

    Directory of Open Access Journals (Sweden)

    Sukmaya LAMA

    2012-07-01

    Full Text Available As the world is invaded by technological inventions and wonders, life becoming more fast and crazy, yet there can be no doubt that the critical factor for the development of a nation or a state is its human resource. The productivity of a nation is influenced by the number of its skilled population. When we look into the problem of underdevelopment from human resource perspective we are bound to take a look at the educational scenario. In India, the higher education scenario has been very sickly, due to the pro profit policies, lack of infrastructure, entry of private players, etc. The growth of distance education phenomenon in India has no doubt brought a ray of hope. The present paper aims to look into the role of distance education in Assam and the potential it carries in building a huge wealth of human resources.

  5. On the Role of Cognitive Abilities in Second Language Vowel Learning.

    Science.gov (United States)

    Ghaffarvand Mokari, Payam; Werner, Stefan

    2018-03-01

    This study investigated the role of different cognitive abilities-inhibitory control, attention control, phonological short-term memory (PSTM), and acoustic short-term memory (AM)-in second language (L2) vowel learning. The participants were 40 Azerbaijani learners of Standard Southern British English. Their perception of L2 vowels was tested through a perceptual discrimination task before and after five sessions of high-variability phonetic training. Inhibitory control was significantly correlated with gains from training in the discrimination of L2 vowel pairs. However, there were no significant correlations between attention control, AM, PSTM, and gains from training. These findings suggest the potential role of inhibitory control in L2 phonological learning. We suggest that inhibitory control facilitates the processing of L2 sounds by allowing learners to ignore the interfering information from L1 during training, leading to better L2 segmental learning.

  6. The Role of ICT in the Teaching and Learning of History in the 21st Century

    Science.gov (United States)

    Adesote, S. A; Fatoki, O. R

    2013-01-01

    This paper examines the role of Information and Communication Technology in the Teaching and Learning of History in the Senior Secondary School in the 21st century. The new Information and communication technologies of internet and multimedia which have led to positive impact in the field of education in most developed countries are still at…

  7. Networking for Learning The role of Networking in a Lifelong Learner's Professional Development

    OpenAIRE

    Rajagopal, Kamakshi

    2016-01-01

    This dissertation discusses the role the social activity of networking plays in lifelong learners’ professional and personal continuous development. The main hypothesis of this thesis is that networking is a learning strategy for lifelong learners, in which conversations are key activities through which they reassess their held thoughts and make sense of their experiences together with others.

  8. The Role of Lecturers and University Administrators in Promoting New E-Learning Initiatives

    Science.gov (United States)

    Mncube, Lancelord Siphamandla; Dube, Luyanda; Ngulube, Patrick

    2017-01-01

    This article examines the role of lecturers in encouraging and supporting students likely to be predisposed to challenges related to incomprehension, incapacity and isolation embedded in the virtual learning environment. This article used a constructivist lens to gain through interviews an understanding into the intuition, thoughts, ideals,…

  9. Learning experiences on role-emerging placements: an exploration from the students' perspective.

    Science.gov (United States)

    Dancza, Karina; Warren, Alison; Copley, Jodie; Rodger, Sylvia; Moran, Monica; McKay, Elizabeth; Taylor, Ann

    2013-12-01

    Occupational therapy educators are challenged to provide students with practical experiences which prepare them for ever changing health-care contexts on graduation. Role-emerging placements have been widely used internationally to help meet this challenge, but research into the learning experiences of students during these innovative placements is limited. This research investigated the enablers and barriers to learning from the perspectives of students on such placements from two European universities. Two separate qualitative studies tracked 10 final year students. Interviews explored their learning experiences prior to, during and after an eight- or 10-week role-emerging placement in a range of settings. Four themes emerged, which were (1) adapting to less doing, more thinking and planning; (2) understanding the complexity of collaboration and making it work; (3) emotional extremes; and (4) realising and using the occupational therapy perspective. These placements presented a 'roller coaster' of authentic learning experiences which created the opportunity for students to use occupation in practice and develop skills for collaborative working in an interprofessional environment. Whereas students viewed their role-emerging placement experiences positively, challenges included the emotional responses of students and placement pace. Findings suggest the need for supportive student placement experiences in both established and role-emerging areas to prepare students for a range of opportunities in an uncertain future. © 2013 Occupational Therapy Australia.

  10. The Role of Electronic Pocket Dictionaries as an English Learning Tool among Chinese Students

    Science.gov (United States)

    Jian, Hua-Li; Sandnes, Frode Eika; Law, Kris M. Y.; Huang, Yo-Ping; Huang, Yueh-Min

    2009-01-01

    This study addressed the role of electronic pocket dictionaries as a language learning tool among university students in Hong Kong and Taiwan. The target groups included engineering and humanities students at both undergraduate and graduate level. Speed of reference was found to be the main motivator for using an electronic pocket dictionary.…

  11. The Roles of Working Memory and Cognitive Load in Geoscience Learning

    Science.gov (United States)

    Jaeger, Allison J.; Shipley, Thomas F.; Reynolds, Stephen J.

    2017-01-01

    Working memory is a cognitive system that allows for the simultaneous storage and processing of active information. While working memory has been implicated as an important element for success in many science, technology, engineering, and mathematics (STEM) fields, its specific role in geoscience learning is not fully understood. The major goal of…

  12. The Role of Emotions, Motivation, and Learning Behavior in Underachievement and Results of an Intervention

    Science.gov (United States)

    Obergriesser, Stefanie; Stoeger, Heidrun

    2015-01-01

    Research has shown that various individual factors play an important role in the underachievement of gifted students. Most often discussed as predictors of underachievement are motivation, learning behavior, and emotions. To examine which specific constructs from these fields simultaneously predict underachievement among gifted fourth graders,…

  13. The Role of IQ in the Use of Cognitive Strategies to Learn Information from a Map

    Science.gov (United States)

    Cho, Seokhee

    2010-01-01

    The role of IQ in individual differences in real-life problem solving and strategies use was explored. Repeated trials of learning and recall of information from a map were analyzed with high IQ and average IQ Korean students. IQ correlated with the selection and use of strategies in recall. However, the performance and strategic behaviors of…

  14. Users' Continuance Intention of Virtual Learning Community Services: The Moderating Role of Usage Experience

    Science.gov (United States)

    Zhang, Min; Liu, Yupei; Yan, Weiwei; Zhang, Yan

    2017-01-01

    Users' continuance intention plays a significant role in the process of information system (IS) service, especially virtual learning community (VLC) services. Following the IS success model and IS post-acceptance model, this study explores the determinants of users' intention to continue using VLCs' service from the perspective of quality,…

  15. Death and Rebirth of Atlántida: The Role of Social Learning in ...

    African Journals Online (AJOL)

    This paper explores the role of social learning in bringing about transformative sustainability processes among individuals and communities. At a time when sustainability is being seriously questioned in terms of what it is and how it can be implemented and evaluated, there are increasing calls to focus instead on ...

  16. Networking for Learning The role of Networking in a Lifelong Learner's Professional Development

    NARCIS (Netherlands)

    Rajagopal, Kamakshi

    2016-01-01

    This dissertation discusses the role the social activity of networking plays in lifelong learners’ professional and personal continuous development. The main hypothesis of this thesis is that networking is a learning strategy for lifelong learners, in which conversations are key activities through

  17. The Role of Guided Induction in Paper-Based Data-Driven Learning

    Science.gov (United States)

    Smart, Jonathan

    2014-01-01

    This study examines the role of guided induction as an instructional approach in paper-based data-driven learning (DDL) in the context of an ESL grammar course during an intensive English program at an American public university. Specifically, it examines whether corpus-informed grammar instruction is more effective through inductive, data-driven…

  18. Massively Multiplayer Online Role-Playing Games as Arenas for Second Language Learning

    Science.gov (United States)

    Peterson, Mark

    2010-01-01

    This article investigates contemporary research on the use of massively multiplayer online role-playing games (MMORPGs) in language education. The development and key features of these games are explored. This is followed by an examination of the theories proposed as a basis for game-based learning, and the claims made regarding the value of…

  19. Using Massively Multiplayer Online Role-Playing Games for Online Learning

    Science.gov (United States)

    Childress, Marcus D.; Braswell, Ray

    2006-01-01

    This article addresses the use of a massively multiplayer online role-playing game (MMORPG) to foster communication and interaction and to facilitate cooperative learning in an online course. The authors delineate the definition and history of massively multiplayer online games (MMOGs), and describe current uses of MMORPGs in education, including…

  20. A Taxonomy of Vocabulary Learning Strategies Used in Massively Multiplayer Online Role-Playing Games

    Science.gov (United States)

    Bytheway, Julie

    2015-01-01

    Initiated in response to informal reports of vocabulary gains from gamers at universities in New Zealand and the Netherlands, this qualitative study explored how English language learners autonomously learn vocabulary while playing massively multiplayer online role-playing games (MMORPGs). Using research processes inherent in Grounded Theory, data…

  1. Moving Theory to Practice: One State's Role in Professional Learning for School and District Leaders

    Science.gov (United States)

    Augustine-Shaw, Donna

    2016-01-01

    As a continuum of professional learning for building and district leaders transitioning from leadership preparation programs into practice, the state of Kansas enacted mentoring and induction requirements as part of their role in supporting development of leadership skills important to on-the-job application of essential knowledge. One approved…

  2. Locus of Control and Individual Learning: The Moderating Role of Interactional Justice

    Science.gov (United States)

    Cappetta, Rossella; Magni, Massimo

    2015-01-01

    Organizations are increasingly investing in training programs for building managerial skills, with a special focus on employees considered "talents" who must be prepared to cover strategic roles within the organization. One of the main goals of such programs is to develop participants' learning in order to tap their potential in a short…

  3. The Role of Computer Technology in Supporting Children's Learning in Jordanian Early Years Education

    Science.gov (United States)

    Alkhawaldeh, Mustafa; Hyassat, Mizyed; Al-Zboon, Eman; Ahmad, Jamal

    2017-01-01

    The current research investigated early years teachers' perspectives regarding the role of computer technology in supporting children's learning in Jordanian kindergartens. Thirty semistructured interviews were conducted with preschool teachers. The sample of kindergartens in this study was purposefully selected from the targeted population of…

  4. Designing After-School Learning Using the Massively Multiplayer Online Role-Playing Game

    Science.gov (United States)

    King, Elizabeth M.

    2015-01-01

    Digital games have become popular for engaging students in a range of learning goals, both in the classroom and the after-school space. In this article, I discuss a specific genre of video game, the massively multiplayer online role-playing game (MMO), which has been identified as a dynamic environment for encountering 21st-century workplace…

  5. An Investigation of the Role of Background Music in IVWs for Learning

    Science.gov (United States)

    Richards, Debbie; Fassbender, Eric; Bilgin, Ayse; Thompson, William Forde

    2008-01-01

    Empirical evidence is needed to corroborate the intuitions of gamers and game developers in understanding the benefits of Immersive Virtual Worlds (IVWs) as a learning environment and the role that music plays within these environments. We report an investigation to determine if background music of the genre typically found in computer-based…

  6. Teaching-Learning Conceptions and Academic Achievement: The Mediating Role of Test Anxiety

    Science.gov (United States)

    Bas, Gökhan

    2016-01-01

    The current research aimed at examining the mediating role of test anxiety in the relationship between teaching-learning conceptions and academic achievement. The correlation investigation model was adopted in this research. The participants of the research were volunteering teachers (n = 108) and students (n = 526) from five different high…

  7. Strategic organisational transformation: The role of learning,leadership and culture

    Directory of Open Access Journals (Sweden)

    K. Viljoen

    2001-12-01

    Full Text Available Today's organisation need to continuously adapts itself to challenges, brought about by modern business environment. This paper argues that leadership, learning and culture play a major role in securing an organisation's ability to face and adapt to these new challenges.

  8. Can we meet the sustainability challenges? The role of education and lifelong learning

    NARCIS (Netherlands)

    Wals, Arjen E.J.; Benavot, Aaron

    2017-01-01

    Education and lifelong learning are increasingly being mobilised to address the global environmental crisis and accompanying sustainability challenges. This article discusses the many roles of education about and for sustainable development, drawing on evidence and arguments put forward in the

  9. Can We Meet the Sustainability Challenges? The Role of Education and Lifelong Learning

    Science.gov (United States)

    Wals, Arjen E. J.; Benavot, Aaron

    2017-01-01

    Education and lifelong learning are increasingly being mobilised to address the global environmental crisis and accompanying sustainability challenges. This article discusses the many roles of education about and for sustainable development, drawing on evidence and arguments put forward in the 2016 Global Education Monitoring Report,…

  10. The role of picture books in young children’s mathematics learning

    NARCIS (Netherlands)

    van den Heuvel-Panhuizen, M.H.A.M; Elia, I.

    2013-01-01

    In this chapter we address the role of picture books in kindergartners’ learning of mathematics. The chapter is based on various studies we carried out on this topic from different perspectives. All studies sought to provide insight into the power of picture books to contribute to the development of

  11. The Role of Teacher Leadership in How Principals Influence Classroom Instruction and Student Learning

    Science.gov (United States)

    Sebastian, James; Allensworth, Elaine; Huang, Haigen

    2016-01-01

    School principals can play an important role in promoting teacher leadership by delegating authority and empowering teachers in ways that allow them influence in key organizational decisions and processes. However, it is unclear whether instruction and student learning are enhanced by promoting teacher influence in all aspects of school…

  12. The Role of an Academic Development Unit in Supporting Institutional VET Learning and Teaching Change Management

    Science.gov (United States)

    Fotinatos, Nina

    2016-01-01

    The aim of this paper is to examine the role and impact of a central academic development unit (ADU) within an institutional strategic and operational change management project. The primary goal of this project was to improve vocational education and training (VET) learning and teaching practice in an Australian dual-sector regional university.…

  13. Workplace Learning within Teacher Education: The Role of Job Characteristics and Goal Orientation

    Science.gov (United States)

    Kyndt, Eva; Donche, Vincent; Gijbels, David; Van Petegem, Peter

    2014-01-01

    Within teacher education, it is widely recognised that internships play a major role in preparing prospective teachers. The current research examines if the learning activities students' undertake in the workplace can be explained by students' goal orientation and their perceptions of the workplace. In addition, it will be investigated…

  14. Coordinated Implicitly? An Empirical Study on the Role of Social Media in Collaborative Learning

    Science.gov (United States)

    Zhang, Xi; Chen, Hui; Ordóñez de Pablos, Patricia; Lytras, Miltiadis D.; Sun, Yongqiang

    2016-01-01

    As social media is widely adopted in collaborative learning, which places teams in a virtual environment, it is critical for teams to identify and leverage the knowledge of their members. Yet little is known about how social media influences teams to coordinate their knowledge and collaborate effectively. In this research, we explore the roles of…

  15. The Role of a Professional Learning Community in Teacher Change: A Perspective from Beliefs and Practices

    Science.gov (United States)

    Tam, Angela Choi Fung

    2015-01-01

    This longitudinal study aimed to examine the role of a professional learning community (PLC) in changing teachers' beliefs and practices. Teachers of a Chinese department in a Hong Kong secondary school were interviewed and observed. The findings indicate that the features of a PLC-facilitating teacher change are development of a coherent…

  16. The Role of Parenting for the Adjustment of Children with and without Learning Disabilities: A Person-Oriented Approach

    Science.gov (United States)

    Barkauskiene, Rasa

    2009-01-01

    A person-oriented approach was used to examine the role of parenting in the associations between single learning disabilities and multiple learning disabilities and the adjustment difficulties in 8-11-year-olds. The results revealed that multiple, but not single, learning disabilities were associated with greater difficulties in emotional and…

  17. An Evaluation of the Pattern between Students' Motivation, Learning Strategies and Their Epistemological Beliefs: The Mediator Role of Motivation

    Science.gov (United States)

    Sen, S.; Yilmaz, A.; Yurdagül, H.

    2014-01-01

    This study aims at analysing the relations between students' achievement motivation, learning strategies and their epistemological beliefs in learning through structural equation modelling, and at exploring the mediation role of motivation in the relations between learning strategies and epistemological beliefs. The study group was composed of 446…

  18. Exploring the Role of the Learning Strategist at a Canadian College and University: The Tale of Two Professionals

    Science.gov (United States)

    Woloshyn, Vera E.; Munn, Caitlin

    2014-01-01

    In this article, we synthesize literature related to the experiences of students with learning disabilities in postsecondary settings, including support service initiatives. We also synthesize the role of the learning strategists in context of working with these students. We then explore the daily experiences of two senior learning strategists…

  19. The role of visual representation in physics learning: dynamic versus static visualization

    Science.gov (United States)

    Suyatna, Agus; Anggraini, Dian; Agustina, Dina; Widyastuti, Dini

    2017-11-01

    This study aims to examine the role of visual representation in physics learning and to compare the learning outcomes of using dynamic and static visualization media. The study was conducted using quasi-experiment with Pretest-Posttest Control Group Design. The samples of this research are students of six classes at State Senior High School in Lampung Province. The experimental class received a learning using dynamic visualization and control class using static visualization media. Both classes are given pre-test and post-test with the same instruments. Data were tested with N-gain analysis, normality test, homogeneity test and mean difference test. The results showed that there was a significant increase of mean (N-Gain) learning outcomes (p physical phenomena and requires long-term observation.

  20. Interactive Role of Organizational Learning and Informal Norms in Accountability and Job Performance in 2014

    Directory of Open Access Journals (Sweden)

    Abolfazl Ghasemzadeh

    2015-09-01

    Full Text Available Introduction: Although the contribution of organizational learning to employee organizational performance is well documented, the mechanisms that explain such relationship remain unclear. Accordingly, the purpose of this paper is to investigate the interactional role of organizational learning and informal norms in accountability and job performance of the staff in a medical department. Methods: The research method of the study is descriptive-correlational type. The statistical population of this study included all staff (N=315 of the Medical Department in Oshnavieh Hospital in 2014. For data gathering in this study, a sample comprising of 180 staff was selected using stratified random sampling. The data were collected through standard questionnaires of Neefe for organizational learning, informal norms of Hall, job performance of Paterson, and the questionnaire of individual accountability of Hochwarter. Pearson and moderated multiple regression analysis were used to test hypotheses. Results: Results showed that organizational learning has a positive and significant correlation with job performance and individual accountability. The results, also, showed a positive and significant correlation between informal norms, personal accountability, and job performance. Regression results showed the interactive role of learning structure dimensions, strategy, and shared vision with informal norms, predicting individual accountability of the staff. Also, interactive role of organizational learning and informal norms was confirmed in predicting job performance of the medical staff. Conclusion: The result of this study hold out that organizational learning directly and with interaction of informal norms improves staffs' performance and accountability. As a result of improved informal norms in a medical setting, we will have staff’s strong accountability and performance.

  1. A role for calcium-permeable AMPA receptors in synaptic plasticity and learning.

    Directory of Open Access Journals (Sweden)

    Brian J Wiltgen

    2010-09-01

    Full Text Available A central concept in the field of learning and memory is that NMDARs are essential for synaptic plasticity and memory formation. Surprisingly then, multiple studies have found that behavioral experience can reduce or eliminate the contribution of these receptors to learning. The cellular mechanisms that mediate learning in the absence of NMDAR activation are currently unknown. To address this issue, we examined the contribution of Ca(2+-permeable AMPARs to learning and plasticity in the hippocampus. Mutant mice were engineered with a conditional genetic deletion of GluR2 in the CA1 region of the hippocampus (GluR2-cKO mice. Electrophysiology experiments in these animals revealed a novel form of long-term potentiation (LTP that was independent of NMDARs and mediated by GluR2-lacking Ca(2+-permeable AMPARs. Behavioral analyses found that GluR2-cKO mice were impaired on multiple hippocampus-dependent learning tasks that required NMDAR activation. This suggests that AMPAR-mediated LTP interferes with NMDAR-dependent plasticity. In contrast, NMDAR-independent learning was normal in knockout mice and required the activation of Ca(2+-permeable AMPARs. These results suggest that GluR2-lacking AMPARs play a functional and previously unidentified role in learning; they appear to mediate changes in synaptic strength that occur after plasticity has been established by NMDARs.

  2. The role of training structure in perceptual learning of accented speech.

    Science.gov (United States)

    Tzeng, Christina Y; Alexander, Jessica E D; Sidaras, Sabrina K; Nygaard, Lynne C

    2016-11-01

    Foreign-accented speech contains multiple sources of variation that listeners learn to accommodate. Extending previous findings showing that exposure to high-variation training facilitates perceptual learning of accented speech, the current study examines to what extent the structure of training materials affects learning. During training, native adult speakers of American English transcribed sentences spoken in English by native Spanish-speaking adults. In Experiment 1, training stimuli were blocked by speaker, sentence, or randomized with respect to speaker and sentence (Variable training). At test, listeners transcribed novel English sentences produced by unfamiliar Spanish-accented speakers. Listeners' transcription accuracy was highest in the Variable condition, suggesting that varying both speaker identity and sentence across training trials enabled listeners to generalize their learning to novel speakers and linguistic content. Experiment 2 assessed the extent to which ordering of training tokens by a single factor, speaker intelligibility, would facilitate speaker-independent accent learning, finding that listeners' test performance did not reliably differ from that in the no-training control condition. Overall, these results suggest that the structure of training exposure, specifically trial-to-trial variation on both speaker's voice and linguistic content, facilitates learning of the systematic properties of accented speech. The current findings suggest a crucial role of training structure in optimizing perceptual learning. Beyond characterizing the types of variation listeners encode in their representations of spoken utterances, theories of spoken language processing should incorporate the role of training structure in learning lawful variation in speech. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. Children's Learning in Scientific Thinking: Instructional Approaches and Roles of Variable Identification and Executive Function

    Science.gov (United States)

    Blums, Angela

    The present study examines instructional approaches and cognitive factors involved in elementary school children's thinking and learning the Control of Variables Strategy (CVS), a critical aspect of scientific reasoning. Previous research has identified several features related to effective instruction of CVS, including using a guided learning approach, the use of self-reflective questions, and learning in individual and group contexts. The current study examined the roles of procedural and conceptual instruction in learning CVS and investigated the role of executive function in the learning process. Additionally, this study examined how learning to identify variables is a part of the CVS process. In two studies (individual and classroom experiments), 139 third, fourth, and fifth grade students participated in hands-on and paper and pencil CVS learning activities and, in each study, were assigned to either a procedural instruction, conceptual instruction, or control (no instruction) group. Participants also completed a series of executive function tasks. The study was carried out with two parts--Study 1 used an individual context and Study 2 was carried out in a group setting. Results indicated that procedural and conceptual instruction were more effective than no instruction, and the ability to identify variables was identified as a key piece to the CVS process. Executive function predicted ability to identify variables and predicted success on CVS tasks. Developmental differences were present, in that older children outperformed younger children on CVS tasks, and that conceptual instruction was slightly more effective for older children. Some differences between individual and group instruction were found, with those in the individual context showing some advantage over the those in the group setting in learning CVS concepts. Conceptual implications about scientific thinking and practical implications in science education are discussed.

  4. mTOR signaling plays a critical role in the defects observed in muscle-derived stem/progenitor cells isolated from a murine model of accelerated aging.

    Science.gov (United States)

    Takayama, Koji; Kawakami, Yohei; Lavasani, Mitra; Mu, Xiaodong; Cummins, James H; Yurube, Takashi; Kuroda, Ryosuke; Kurosaka, Masahiro; Fu, Freddie H; Robbins, Paul D; Niedernhofer, Laura J; Huard, Johnny

    2017-07-01

    Mice expressing reduced levels of ERCC1-XPF (Ercc1 -/Δ mice) demonstrate premature onset of age-related changes due to decreased repair of DNA damage. Muscle-derived stem/progenitor cells (MDSPCs) isolated from Ercc1 -/Δ mice have an impaired capacity for cell differentiation. The mammalian target of rapamycin (mTOR) is a critical regulator of cell growth in response to nutrient, hormone, and oxygen levels. Inhibition of the mTOR pathway extends the lifespan of several species. Here, we examined the role of mTOR in regulating the MDSPC dysfunction that occurs with accelerated aging. We show that mTOR signaling pathways are activated in Ercc1 -/Δ MDSPCs compared with wild-type (WT) MDSPCs. Additionally, inhibiting mTOR with rapamycin promoted autophagy and improved the myogenic differentiation capacity of the Ercc1 -/Δ MDSPCs. The percent of apoptotic and senescent cells in Ercc1 -/Δ MDSPC cultures was decreased upon mTOR inhibition. These results establish that mTOR signaling contributes to stem cell dysfunction and cell fate decisions in response to endogenous DNA damage. Therefore, mTOR represents a potential therapeutic target for improving defective, aged stem cells. © 2016 The Authors. Journal of Orthopaedic Research Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 35:1375-1382, 2017. © 2016 The Authors. Journal of Orthopaedic Research Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society.

  5. Tissue-Specific Methylation of Long Interspersed Nucleotide Element-1 of Homo Sapiens (L1Hs) During Human Embryogenesis and Roles in Neural Tube Defects.

    Science.gov (United States)

    Wang, L; Chang, S; Guan, J; Shangguan, S; Lu, X; Wang, Z; Wu, L; Zou, J; Zhao, H; Bao, Y; Qiu, Z; Niu, B; Zhang, T

    2015-01-01

    Epigenetic regulation of long interspersed nucleotide element-1 (LINE-1) retrotransposition events plays crucial roles during early development. Previously we showed that LINE-1 hypomethylation in neuronal tissues is associated with pathogenesis of neural tube defect (NTD). Herein, we further evaluated LINE-1 Homo sapiens (L1Hs) methylation in tissues derived from three germ layers of stillborn NTD fetuses, to define patterns of tissue specific methylation and site-specific hypomethylation at CpG sites within an L1Hs promoter region. Stable, tissue-specific L1Hs methylation patterns throughout three germ layer lineages of the fetus, placenta, and maternal peripheral blood were observed. Samples from maternal peripheral blood exhibited the highest level of L1Hs methylation (64.95%) and that from placenta showed the lowest (26.82%). Between samples from NTDs and controls, decrease in L1Hs methylation was only significant in NTD-affected brain tissue at 7.35%, especially in females (8.98%). L1Hs hypomethylation in NTDs was also associated with a significant increase in expression level of an L1Hs-encoded transcript in females (r = -0.846, p = 0.004). This could be due to genomic DNA instability and alternation in chromatins accessibility resulted from abnormal L1Hs hypomethylation, as showed in this study with HCT-15 cells treated with methylation inhibitor 5-Aza.

  6. THE ROLE OF THE SPEECH THERAPIST AND HIS INFLUENCE IN SPEECH DEVELOPMENT OF CHILDREN WITH CENTRAL DEFECTS AND INSTRUCTIVE AND ADVISORY WORK OF THE PARENT

    Directory of Open Access Journals (Sweden)

    Violeta TORTEVSKA

    1997-06-01

    Full Text Available The modern way of living in which the communication becomes a basic and upbringing factor and regulator of the relations isolates children with hard individual, family, educative and social problems.The speech and language disorders are the most remarkable symptoms pointing out the complex of defects in the communicative activities, reduced cognitive functions and cerebral dysfunction's.The modern conception in the rehabilitation field leads to a full engagement of the children’s closest environment and especially parents.The study will include the work of the speech therapist with children with a diagnosis tardy speech development (alalia and developing dysphasia in the hearing, speech and voice rehabilitation institute-Skopje, and its role introducing the parents for their right access and the systematic conduction of the rehabilitation proceedings-especially stimulating the motors and speech development.The speech therapist’s task is to find out a way and to apply means by which the children with central damages could build their speech and lingual system and to help the parents through instructive and advisory work into the comprehension of the phases and stages of that system.The conclusion is that the proceedings of the early treatment with the children with central damages are naturally caused by the difference of their early supplementation. The suggestions that are referring to what should be substituted, how much it should be substituted and how it should be done leads to the frames of the early therapeutical access.

  7. Role of graphene on the surface chemical reactions of BiPO4-rGO with low OH-related defects.

    Science.gov (United States)

    Gao, Erping; Wang, Wenzhong

    2013-11-21

    Graphene has been widely introduced into photocatalysis to enhance photocatalytic performance due to its unique physical and chemical properties. However, the effect of graphene on the surface chemical reactions of photocatalysis has not been clearly researched, which is important for photocatalysis because photocatalytic reactions ultimately occur on the catalyst surface. Herein, a two-step solution-phase reaction has been designed to synthesize quasi-core-shell structured BiPO4-rGO cuboids and the role of graphene on the surface chemical reactions was investigated in detail. It was found that the introduced graphene modified the process and the mechanism of the surface chemical reactions. The change mainly originates from the interaction between graphene and the adsorbed O2 molecule. Due to the electron transfer from graphene to adsorbed O2, graphene could tune the interfacial charge transport and efficiently activate molecular oxygen to form O2˙(-) anions as the major oxidation species instead of ˙OH. In addition, the two-step synthesis approach could efficiently suppress the formation of OH-related defects in the lattice. As a result, the BiPO4-rGO composite exhibited superior photocatalytic activity to BiPO4 and P25, about 4.3 times that of BiPO4 and 6.9 times that of P25.

  8. Adventures in Learning: Creating Role Playing Video Games to Teach and Learn Economics

    OpenAIRE

    Catherine L. Lawson; Larry L. Lawson

    2010-01-01

    This article examines pedagogical lessons derived from the learning theory embodied in commercially successfully video games and their link to reported increases in 'fluid intelligence' of student populations. The scholarly literature in this area is reviewed in order to elicit practical principles by which to guide the development of instructional video game modules for the teaching of economics. The authors' experiences in developing and pilot testing such a module, and in subsequently guid...

  9. Reviewing the Role of Mobile Learning Technology in Special Operations Forces Language Learning Contexts

    Science.gov (United States)

    2013-03-01

    could be used as a change-of-pace option to add variety to IAT and increase (or regain) student engagement . It is important to note language resources...courses’ virtual learning environment (VLE) so tutors could provide feedback (Belanger, 2005). The results of this study indicated that student ... engagement and interest in class discussions increased as a result of the iPods, and that location-independent access to digital course materials led to

  10. Reciprocal Benefits, Legacy and Risk: Applying Ellinger and Bostrom's Model of Line Manager Role Identity as Facilitators of Learning

    Science.gov (United States)

    Campbell, Paul; Evans, Peter

    2016-01-01

    Purpose: The purpose of this paper is to explore the beliefs held by managers about their roles as facilitators of learning with their employees in a public utilities organisation. Design/methodology/approach: The research was based on Ellinger and Bostrom's (2002) study on managers' beliefs on their role as facilitators of learning in…

  11. Evidence for a developmental role for TLR4 in learning and memory.

    Directory of Open Access Journals (Sweden)

    Eitan Okun

    Full Text Available Toll-like receptors (TLRs play essential roles in innate immunity and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain where they mediate responses to infection, stress and injury. Very little is known about the roles of TLRs in cognition. To test the hypothesis that TLR4 has a role in hippocampus-dependent spatial learning and memory, we used mice deficient for TLR4 and mice receiving chronic TLR4 antagonist infusion to the lateral ventricles in the brain. We found that developmental TLR4 deficiency enhances spatial reference memory acquisition and memory retention, impairs contextual fear-learning and enhances motor functions, traits that were correlated with CREB up-regulation in the hippocampus. TLR4 antagonist infusion into the cerebral ventricles of adult mice did not affect cognitive behavior, but instead affected anxiety responses. Our findings indicate a developmental role for TLR4 in shaping spatial reference memory, and fear learning and memory. Moreover, we show that central TLR4 inhibition using a TLR4 antagonist has no discernible physiological role in regulating spatial and contextual hippocampus-dependent cognitive behavior.

  12. The Role of Age and Executive Function in Auditory Category Learning

    Science.gov (United States)

    Reetzke, Rachel; Maddox, W. Todd; Chandrasekaran, Bharath

    2015-01-01

    Auditory categorization is a natural and adaptive process that allows for the organization of high-dimensional, continuous acoustic information into discrete representations. Studies in the visual domain have identified a rule-based learning system that learns and reasons via a hypothesis-testing process that requires working memory and executive attention. The rule-based learning system in vision shows a protracted development, reflecting the influence of maturing prefrontal function on visual categorization. The aim of the current study is two-fold: (a) to examine the developmental trajectory of rule-based auditory category learning from childhood through adolescence, into early adulthood; and (b) to examine the extent to which individual differences in rule-based category learning relate to individual differences in executive function. Sixty participants with normal hearing, 20 children (age range, 7–12), 21 adolescents (age range, 13–19), and 19 young adults (age range, 20–23), learned to categorize novel dynamic ripple sounds using trial-by-trial feedback. The spectrotemporally modulated ripple sounds are considered the auditory equivalent of the well-studied Gabor patches in the visual domain. Results revealed that auditory categorization accuracy improved with age, with young adults outperforming children and adolescents. Computational modeling analyses indicated that the use of the task-optimal strategy (i.e. a conjunctive rule-based learning strategy) improved with age. Notably, individual differences in executive flexibility significantly predicted auditory category learning success. The current findings demonstrate a protracted development of rule-based auditory categorization. The results further suggest that executive flexibility coupled with perceptual processes play important roles in successful rule-based auditory category learning. PMID:26491987

  13. Serine biosynthesis and transport defects.

    Science.gov (United States)

    El-Hattab, Ayman W

    2016-07-01

    l-serine is a non-essential amino acid that is biosynthesized via the enzymes phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Besides its role in protein synthesis, l-serine is a potent neurotrophic factor and a precursor of a number of essential compounds including phosphatidylserine, sphingomyelin, glycine, and d-serine. Serine biosynthesis defects result from impairments of PGDH, PSAT, or PSP leading to systemic serine deficiency. Serine biosynthesis defects present in a broad phenotypic spectrum that includes, at the severe end, Neu-Laxova syndrome, a lethal multiple congenital anomaly disease, intermediately, infantile serine biosynthesis defects with severe neurological manifestations and growth deficiency, and at the mild end, the childhood disease with intellectual disability. A serine transport defect resulting from deficiency of the ASCT1, the main transporter for serine in the central nervous system, has been recently described in children with neurological manifestations that overlap with those observed in serine biosynthesis defects. l-serine therapy may be beneficial in preventing or ameliorating symptoms in serine biosynthesis and transport defects, if started before neurological damage occurs. Herein, we review serine metabolism and transport, the clinical, biochemical, and molecular aspects of serine biosynthesis and transport defects, the mechanisms of these diseases, and the potential role of serine therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Facilitating pragmatic skills through role-play in learners with language learning disability.

    Science.gov (United States)

    Abdoola, Fareeaa; Flack, Penelope S; Karrim, Saira B

    2017-07-26

    Role-based learning involves the process whereby learners acquire skills, knowledge and understanding through the assumption of roles within real-life settings. Role-play holds potential as an effective learning strategy for children; however, there is limited research on the use of role-play as a therapy method within the field of speech-language pathology. Children with language learning disability (LLD) typically present with difficulties in social communication, which can negatively affect their social and academic achievement. The aim of this study was to determine the effectiveness of role-play as a therapy approach targeting the pragmatic skills of stylistic variation and requesting for clarification in learners with LLD. The use of combined positivist and interpretivist paradigms allowed for the implementation of an embedded mixed methods design. An experimental pretest-posttest design was implemented. Eight participants, who were learners with a diagnosis of LLD, were purposefully selected. Data collection was conducted over five phases, utilising the Clinical Evaluation of Language Fundamentals (4th Ed.) Pragmatics Profile, discourse completion tasks, session plans and session records. Quantitative data were analysed using descriptive statistics and were supplemented by qualitative data from session records. Results revealed improvements in stylistic variation and requesting for clarification post role-play intervention, with minimal changes in the control group. Limitations of the study have been reported for consideration when interpreting results. Role-play as a therapy approach targeting two pragmatic skills, stylistic variation and requesting for clarification, was found to be beneficial for learners with LLD. Recommendations for the implementation of role-play as a therapy approach were made.

  15. Facilitating pragmatic skills through role-play in learners with language learning disability

    Directory of Open Access Journals (Sweden)

    Fareeaa Abdoola

    2017-07-01

    Full Text Available Background: Role-based learning involves the process whereby learners acquire skills, knowledge and understanding through the assumption of roles within real-life settings. Role-play holds potential as an effective learning strategy for children; however, there is limited research on the use of role-play as a therapy method within the field of speech-language pathology. Children with language learning disability (LLD typically present with difficulties in social communication, which can negatively affect their social and academic achievement. Aim: The aim of this study was to determine the effectiveness of role-play as a therapy approach targeting the pragmatic skills of stylistic variation and requesting for clarification in learners with LLD. Method: The use of combined positivist and interpretivist paradigms allowed for the implementation of an embedded mixed methods design. An experimental pretest-posttest design was implemented. Eight participants, who were learners with a diagnosis of LLD, were purposefully selected. Data collection was conducted over five phases, utilising the Clinical Evaluation of Language Fundamentals (4th Ed. Pragmatics Profile, discourse completion tasks, session plans and session records. Quantitative data were analysed using descriptive statistics and were supplemented by qualitative data from session records. Results: Results revealed improvements in stylistic variation and requesting for clarification post role-play intervention, with minimal changes in the control group. Limitations of the study have been reported for consideration when interpreting results. Conclusion: Role-play as a therapy approach targeting two pragmatic skills, stylistic variation and requesting for clarification, was found to be beneficial for learners with LLD. Recommendations for the implementation of role-play as a therapy approach were made.

  16. Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective.

    Science.gov (United States)

    Rowe, Anna D; Fitness, Julie

    2018-02-20

    The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom) were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame) mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement.

  17. Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective

    Directory of Open Access Journals (Sweden)

    Anna D. Rowe

    2018-02-01

    Full Text Available The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement.

  18. Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective

    Science.gov (United States)

    Fitness, Julie

    2018-01-01

    The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom) were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame) mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement. PMID:29461487

  19. The role of service-learning in college students' environmental literacy: Content knowledge, attitudes, and behaviors

    Science.gov (United States)

    Singletary, Joanna Lynn Bush

    This study evaluated the relationship of environmental service-learning on environmental literacy in undergraduates. The subjects were 36 undergraduates at a small liberal arts university enrolled in an environmental biology course. To determine the role of environmental service-learning on college students' environmental knowledge, attitudes, behaviors, and environmental literacy, this study utilized concurrent mixed methods approach for qualitative and quantitative analysis. A quasi-experimental repeated measures approach was the design of the quantitative component of the study. Data were collected on attitude, behavior, and content knowledge aspects of environmental literacy as measured by the Environmental Literacy Survey (Kibert, 2000). Hypotheses were tested by independent samples ttests and repeated measures ANOVA. Repeated measures ANOVA conducted on participants' three subscales scores for the Environmental Literacy Survey (attitude, behavior, and knowledge) indicated that students who participated in environmental service-learning scored statistically significantly higher than those that did not initially participate in service-learning. Qualitative data collected in the form of journal reflections and portfolios were evaluated for themes of environmental attitudes or affective statements, environmentally positive behaviors and skills, and ecological content. Quantitative and qualitative data support the positive role of environmental service-learning in the development of environmental literacy in undergraduate students.

  20. How doctors learn: the role of clinical problems across the medical school-to-practice continuum.

    Science.gov (United States)

    Slotnick, H B

    1996-01-01

    The author proposes a theory of how physicians learn that uses clinical problem solving as its central feature. His theory, which integrates insights from Maslow, Schön, Norman, and others, claims that physicians-in-training and practicing physicians learn largely by deriving insights from clinical experience. These insights allow the learner to solve future problems and thereby address the learner's basic human needs for security, affiliation, and self-esteem. Ensuring that students gain such insights means that the proper roles of the teacher are (1) to select problems for students to solve and offer guidance on how to solve them, and (2) to serve as a role model of how to reflect on the problem, its solution, and the solution's effectiveness. Three principles guide instruction within its framework for learning: (1) learners, whether physicians-in-training or practicing physicians, seek to solve problems they recognize they have; (2) learners want to be involved in their own learning; and (3) instruction must both be time-efficient and also demonstrate the range of ways in which students can apply what they learn. The author concludes by applying the theory to an aspect of undergraduate education and to the general process of continuing medical education.

  1. Role of Personality Traits, Learning Styles and Metacognition in Predicting Critical Thinking of Undergraduate Students

    Directory of Open Access Journals (Sweden)

    Soliemanifar O

    2015-04-01

    The aim of this study was to investigate the role of personality traits, learning styles and metacognition in predicting critical thinking. Instrument & Methods: In this descriptive correlative study, 240 students (130 girls and 110 boys of Ahvaz Shahid Chamran University were selected by multi-stage random sampling method. The instruments for collecting data were NEO Five-Factor Inventory, learning style inventory of Kolb (LSI, metacognitive assessment inventory (MAI of Schraw & Dennison (1994 and California Critical Thinking Skills Test (CCTST. The data were analyzed using Pearson correlation coefficient, stepwise regression analysis and Canonical correlation analysis.  Findings: Openness to experiment (b=0.41, conscientiousness (b=0.28, abstract conceptualization (b=0.39, active experimentation (b=0.22, reflective observation (b=0.12, knowledge of cognition (b=0.47 and regulation of cognition (b=0.29 were effective in predicting critical thinking. Openness to experiment and conscientiousness (r2=0.25, active experimentation, abstract conceptualization and reflective observation learning styles (r2=0.21 and knowledge and regulation of cognition metacognitions (r2=0.3 had an important role in explaining critical thinking. The linear combination of critical thinking skills (evaluation, analysis, inference was predictable by a linear combination of dispositional-cognitive factors (openness, conscientiousness, abstract conceptualization, active experimentation, knowledge of cognition and regulation of cognition. Conclusion: Personality traits, learning styles and metacognition, as dispositional-cognitive factors, play a significant role in students' critical thinking.

  2. The role of learning environment on high school chemistry students' motivation and self-regulatory processes

    Science.gov (United States)

    Judd, Jeffrey S.

    Changes to the global workforce and technological advancements require graduating high school students to be more autonomous, self-directed, and critical in their thinking. To reflect societal changes, current educational reform has focused on developing more problem-based, collaborative, and student-centered classrooms to promote effective self-regulatory learning strategies, with the goal of helping students adapt to future learning situations and become life-long learners. This study identifies key features that may characterize these "powerful learning environments", which I term "high self-regulating learning environments" for ease of discussion, and examine the environment's role on students' motivation and self-regulatory processes. Using direct observation, surveys, and formal and informal interviews, I identified perceptions, motivations, and self-regulatory strategies of 67 students in my high school chemistry classes as they completed academic tasks in both high and low self-regulating learning environments. With social cognitive theory as a theoretical framework, I then examined how students' beliefs and processes changed after they moved from low to a high self-regulating learning environment. Analyses revealed that key features such as task meaning, utility, complexity, and control appeared to play a role in promoting positive changes in students' motivation and self-regulation. As embedded cases, I also included four students identified as high self-regulating, and four students identified as low self-regulating to examine whether the key features of high and low self-regulating learning environments played a similar role in both groups. Analysis of findings indicates that key features did play a significant role in promoting positive changes in both groups, with high self-regulating students' motivation and self-regulatory strategies generally remaining higher than the low self-regulating students; this was the case in both environments. Findings

  3. Charged Semiconductor Defects Structure, Thermodynamics and Diffusion

    CERN Document Server

    Seebauer, Edmund G

    2009-01-01

    The technologically useful properties of a solid often depend upon the types and concentrations of the defects it contains. Not surprisingly, defects in semiconductors have been studied for many years, in many cases with a view towards controlling their behavior through various forms of "defect engineering." For example, in the bulk, charging significantly affects the total concentration of defects that are available to mediate phenomena such as solid-state diffusion. Surface defects play an important role in mediating surface mass transport during high temperature processing steps such as epitaxial film deposition, diffusional smoothing in reflow, and nanostructure formation in memory device fabrication. Charged Semiconductor Defects details the current state of knowledge regarding the properties of the ionized defects that can affect the behavior of advanced transistors, photo-active devices, catalysts, and sensors. Features: Group IV, III-V, and oxide semiconductors; Intrinsic and extrinsic defects; and, P...

  4. THE MEDIATING ROLE OF SCIENCE MUSEUM IN STRUCTURING AND SYNTHESIS OF LEARNING

    Directory of Open Access Journals (Sweden)

    Fanny Angulo Delgado

    2016-10-01

    Full Text Available Understanding the mediating role of science museum in learning scientific content in school, it involves reflecting on the contributions of research to the question of what and how people learn in non-conventional educational settings. It has been shown that most people spend less than 3% of their lives learning in school, which emphasizes the importance of conceptualizing what they are and how much of their learning take place. While that question is resolved, it speaks at this bioassay on the complementary relationship between the museum and the school, as both institutions share the same educational purpose, but differ in the ways of achieving it. The science museum joins the class as a mediator that facilitates student learning as part of an education that promotes understanding of the phenomena of the world through models, which means that school learning goes in stages, one of which is that students have opportunity to structure new knowledge and synthesize on its own model. For this it is necessary that students speak, read, listen and write in science class, while the thought is expressed in language to attest to the facts. These communication skills arise in science class as indicators of mediation exercised by the museum and allow us to understand that it takes place in at least two dimensions: museographic and didactics.

  5. The role of socio-cognitive variables in predicting learning satisfaction in smart schools

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Firoozi

    2017-03-01

    Full Text Available The present study aimed to investigate the role of Socio-Cognitive variables in predicting learning satisfaction in Smart Schools. The population was all the primary school students studying in smart schools in the city of Shiraz in the school year 2014-2015. The sample, randomly chosen through multi-stage cluster sampling, was 383 primary school students studying in smart schools in Shiraz. The instruments were the Computer Self-Efficiency Questionnaire developed by Torkzadeh (2003, Performance Expectation Questionnaire developed by Compeau and Higgins (1995, System Functionality and Content Feature Questionnaire developed by Pituch and Lee (2006, Interaction Questionnaire developed by Johnston, Killion and Oomen (2005, Learning Climate Questionnaire developed by Chou` and Liu (2005 and Learning Satisfaction Questionnaire developed by Chou and Liu (2005. In order to determine the possible relationship between variables and to predict the changes in the degree of satisfaction, we made use of correlational procedures and step-wise regression analysis. The results indicated that all the socio-cognitive variables have a positive and significant correlation with learning satisfaction. Out of the socio-cognitive variables in question, Computer Self-Efficiency, Performance Expectation and Learning Climate significantly explained 53% of the variance of learning satisfaction.

  6. The Role of Socio-Cognitive Variables in Predicting Learning Satisfaction in Smart Schools

    Directory of Open Access Journals (Sweden)

    Mohammad Reza FIROOZI

    2017-03-01

    Full Text Available The present study aimed to investigate the role of Socio-Cognitive variables in predicting learning satisfaction in Smart Schools. The population was all the primary school students studying in smart schools in the city of Shiraz in the school year 2014-2015. The sample, randomly chosen through multi-stage cluster sampling, was 383 primary school students studying in smart schools in Shiraz. The instruments were the Computer Self-Efficiency Questionnaire developed by Torkzadeh (2003, Performance Expectation Questionnaire developed by Compeau and Higgins (1995, System Functionality and Content Feature Questionnaire developed by Pituch and Lee (2006, Interaction Questionnaire developed by Johnston, Killion and Oomen (2005, Learning Climate Questionnaire developed by Chou` and Liu (2005 and Learning Satisfaction Questionnaire developed by Chou and Liu (2005. In order to determine the possible relationship between variables and to predict the changes in the degree of satisfaction, we made use of correlational procedures and step-wise regression analysis. The results indicated that all the socio-cognitive variables have a positive and significant correlation with learning satisfaction. Out of the socio-cognitive variables in question, Computer Self-Efficiency, Performance Expectation and Learning Climate significantly explained 53% of the variance of learning satisfaction.

  7. Lessons Learned from Delayed Versus Immediate Microsurgical Reconstruction of Complex Maxillectomy and Midfacial Defects: Experience in a Tertiary Center in Mexico.

    Science.gov (United States)

    Santamaria, Eric; de la Concha, Erika

    2016-10-01

    Microsurgical reconstruction of complex midfacial and maxillectomy defects is among the most challenging procedures in plastic surgery, and it often requires composite flaps to improve functional and aesthetic results. Various factors have been identified as having influence in the outcome of microsurgical reconstruction. In this article, the authors present their experience with immediate and delayed reconstruction of complex maxillectomy defects in a tertiary center in Mexico. The authors present a total of 37 patients with microsurgical reconstruction of a complex maxillectomy defect; 13 patients had immediate and 24 had delayed reconstructions. The authors recommend doing immediate reconstruction when feasible. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. What Drives Students' Loyalty-Formation in Social Media Learning within a Personal Learning Environment Approach? The Moderating Role of Need for Cognition

    Science.gov (United States)

    Arquero, José L.; del Barrio-García, Salvador; Romero-Frías, Esteban

    2017-01-01

    Our study analyzes an educational experience based on the integrated use of social media within a higher education course under a personal learning environment approach and investigates the factors that determine students' loyalty to social media learning. We examined the moderating role of need for cognition (NFC) in students' formation of…

  9. The Impact of Taiwanese College Students' Learning Motivation from Self-Determination Perspective on Learning Outcomes: Moderating Roles of Multi-Traits

    Science.gov (United States)

    Ho, Sophia Shi-Huei

    2017-01-01

    The purpose of this study is to explore the associations among learning motivation, engagement and outcomes, and the moderating role of various traits in the relationship between deep approaches to learning and outcomes. Based on data from 2,340 students in multiple universities in Taiwan, this study proposes two alternative models, tested by…

  10. The Role of Interactional Quality in Learning from Touch Screens during Infancy: Context Matters

    Directory of Open Access Journals (Sweden)

    Elizabeth Zack

    2016-08-01

    Full Text Available Interactional quality has been shown to enhance learning during book reading and play, but has not been examined during touch screen use. Learning to apply knowledge from a touch screen is complex for infants because it involves transfer of learning between a 2-dimensional (2D screen and 3-dimensional (3D object in the physical world. This study uses a touch screen procedure to examine interactional quality measured via maternal structuring, diversity of maternal language, and dyadic emotional responsiveness and infant outcomes during a transfer of learning task. Fifty 15-month-old infants and their mothers participated in this semi-naturalistic teaching task. Mothers were given a 3D object, and a static image of the object presented on a touch screen. Mothers had 5 minutes to teach their infant that a button on the real toy works in the same way as a virtual button on the touch screen (or vice versa. Overall, 64% of infants learned how to make the button work, transferring learning from the touch screen to the 3D object or vice versa. Infants were just as successful in the 3D to 2D transfer direction as they were in the 2D to 3D transfer direction. A cluster analysis based on emotional responsiveness, the proportion of diverse maternal verbal input, and amount of maternal structuring resulted in two levels of interactional quality: high quality and moderate quality. A logistic regression revealed the level of interactional quality predicted infant transfer. Infants were 19 times more likely to succeed and transfer learning between the touch screen and real object if they were in a high interactional quality dyad, even after controlling for infant activity levels. The present findings suggest that interactional quality between mother and infant plays an important role in making touch screens effective teaching tools for infants’ learning.

  11. The Role of Interactional Quality in Learning from Touch Screens during Infancy: Context Matters.

    Science.gov (United States)

    Zack, Elizabeth; Barr, Rachel

    2016-01-01

    Interactional quality has been shown to enhance learning during book reading and play, but has not been examined during touch screen use. Learning to apply knowledge from a touch screen is complex for infants because it involves transfer of learning between a two-dimensional (2D) screen and three-dimensional (3D) object in the physical world. This study uses a touch screen procedure to examine interactional quality measured via maternal structuring, diversity of maternal language, and dyadic emotional responsiveness and infant outcomes during a transfer of learning task. Fifty 15-month-old infants and their mothers participated in this semi-naturalistic teaching task. Mothers were given a 3D object, and a static image of the object presented on a touch screen. Mothers had 5 min to teach their infant that a button on the real toy works in the same way as a virtual button on the touch screen (or vice versa). Overall, 64% of infants learned how to make the button work, transferring learning from the touch screen to the 3D object or vice versa. Infants were just as successful in the 3D to 2D transfer direction as they were in the 2D to 3D transfer direction. A cluster analysis based on emotional responsiveness, the proportion of diverse maternal verbal input, and amount of maternal structuring resulted in two levels of interactional quality: high quality and moderate quality. A logistic regression revealed the level of interactional quality predicted infant transfer. Infants were 19 times more likely to succeed and transfer learning between the touch screen and real object if they were in a high interactional quality dyad, even after controlling for infant activity levels. The present findings suggest that interactional quality between mother and infant plays an important role in making touch screens effective teaching tools for infants' learning.

  12. The role of blended learning in the clinical education of healthcare students: a systematic review.

    Science.gov (United States)

    Rowe, Michael; Frantz, Jose; Bozalek, Vivienne

    2012-01-01

    Developing practice knowledge in healthcare is a complex process that is difficult to teach. Clinical education exposes students to authentic learning situations, but students also need epistemological access to tacit knowledge and clinical reasoning skills in order to interpret clinical problems. Blended learning offers opportunities for the complexity of learning by integrating face-to-face and online interaction. However, little is known about its use in clinical education. To determine the impact of blended learning in the clinical education of healthcare students. Articles published between 2000 and 2010 were retrieved from online and print sources, and included multiple search methodologies. Search terms were derived following a preliminary review of relevant literature. A total of 71 articles were retrieved and 57 were removed after two rounds of analysis. Further methodological appraisals excluded another seven, leaving seven for the review. All studies reviewed evaluated the use of a blended learning intervention in a clinical context, although each intervention was different. Three studies included a control group, and two were qualitative in nature. Blended learning was shown to help bridge the gap between theory and practice and to improve a range of selected clinical competencies among students. Few high-quality studies were found to evaluate the role of blended learning in clinical education, and those that were found provide only rudimentary evidence that integrating technology-enhanced teaching with traditional approaches have potential to improve clinical competencies among health students. Further well-designed research into the use of blended learning in clinical education is therefore needed before we rush to adopt it.

  13. Boosting Autonomous Foreign Language Learning: Scrutinizing the Role of Creativity, Critical Thinking, and Vocabulary Learning Strategies

    Directory of Open Access Journals (Sweden)

    Mania Nosratinia

    2015-07-01

    Full Text Available This study set out to investigate the association among English language learners' Autonomy (AU, Creativity (CR, Critical Thinking (CT, and Vocabulary Learning Strategies (VLS. The participants of this study were 202 randomly selected male and female undergraduate (English as a Foreign Language EFL learners, between the ages of 19 and 26 (Mage = 22 years. These participants filled out four questionnaires estimating their AU, CR, CT, and VLS. The characteristics of the collected data legitimated running Pearson's product-moment correlation coefficient. The results suggested that there is a significant and positive relationship between EFL learners' AU and CR, AU and CT, AU and VLS, CR and CT, CR and VLS, as well as their CT and VLS. Considering AU as the predicted variable for this study, it was confirmed that CT is the best predictor of AU. The article concludes with some pedagogical implications and some avenues for future research.

  14. Role of recombination in repair and UV-mutagenesis in Saccharomyces cerevisiae : studies with mutants defective in X-ray and UV-induced intragenic mitotic recombination

    International Nuclear Information System (INIS)

    Vashishat, R.K.; Kakar, S.N.

    1977-01-01

    In order to study the role of recombination in repair of radiation damage and damage caused by chemical mutagens, studies were conducted on two recombination deficient strains 2c r(rec 5) and 2c 8(rec 4) isolated from Z140-51C. These strains are disomic for chromosome VIII and defective in X-ray and UV-induced intragenic mitotic recombination. The strain 2c 4 was sensitive to UV, HNO 2 , EMS and NG but it was as resistant to X-rays as the wild-type strain. Strain 2c 8 was sensitive to NG and showed more or less wild-type resistance to other mutagens. All the strains showed a decrease in UV-survival when caffeine (1g/1) was present in the post-irradiation medium. There was an increase in viability by photoreactivation. A comparison of UV-induced reversion at ade 2 and his 5 loci in rec strains and parental strain showed that total frequency of UV-induced revertants for ade 2 in all the strains was less than that for his 5. The frequency of total revertants for ade 2 was same in wild-type and 2c 8 but it was higher for his 5 in strain 2c 8. The total frequency of UV-induced revertants for both loci was less in 2c 4 as compared to wild-type. It is concluded that recombination is involved in repair of damage caused by UV light and chemical mutagens and in UV-induced mutations. (author)

  15. Effects of e-learning, lectures, and role playing on nursing students' knowledge acquisition, retention and satisfaction.

    Science.gov (United States)

    Pourghaznein, Tayebeh; Sabeghi, Hakimeh; Shariatinejad, Keyvan

    2015-01-01

    Nursing education can maintain its dynamic quality when it moves toward innovation and modern methods of teaching and learning. Therefore, teachers are required to employ up to date methods in their teaching plans. This study evaluated the effects of e-learning, lectures, and role playing on nursing students' learning, retention, and satisfaction. Sixty nursing students were selected as an experiment and control groups during two consecutive semesters. The educational content was presented as e-learning and role playing during one semester (experiment group) and as lectures in the next semester (control group). A questionnaire containing three parts was used to assess demographics, learning and satisfaction statuses. The questionnaire also included a final openended question to evaluate the students' ideas about the whole course. The mean scores of posttest were 16.13 ± 1.37 using role playing, 15.50 ± 1.44 using e-learning and 16.45 ± 1.23 using lectures. The differences between the mean scores of posttest and pretest were 12.84 ± 1.43, 12.56 ± 1.57, and 13.73 ± 1.53 in the mentioned methods, respectively. Lectures resulted in significantly better learning compared to role playing and e-learning. In contrast, retention rates were significantly lower using lectures than using role playing and e-learning. Students' satisfaction from e-learning was significantly lower than lecturing and role playing. Due to the lower rates of retention following lectures, the teachers are recommended to use student- centered approaches in their lectures. Since students' satisfaction with e-learning was lower than the other methods, further studies are suggested to explore the problems of e-learning in Iran.

  16. What roles do errors serve in motor skill learning? An examination of two theoretical predictions.

    Science.gov (United States)

    Sanli, Elizabeth A; Lee, Timothy D

    2014-01-01

    Easy-to-difficult and difficult-to-easy progressions of task difficulty during skill acquisition were examined in 2 experiments that assessed retention, dual-task, and transfer tests of learning. Findings of the first experiment suggest that an easy-to difficult progression did not consistently induce implicit learning processes and was not consistently beneficial to performance under a secondary-task load. The findings of experiment two did not support the predictions made based on schema theory and only partially supported predictions based on reinvestment theory. The authors interpret these findings to suggest that the timing of error in relation to the difficulty of the task (functional task difficulty) plays a role in the transfer of learning to novel versions of a task.

  17. Teamwork orientation and personal learning: The role of individual cultural values and value congruence

    Directory of Open Access Journals (Sweden)

    Ghulam Mustafa

    2017-11-01

    Full Text Available Orientation: There is a growing body of research that indicates that personal factors such as collectivist value orientation play an important role in individuals’ preference for teamwork, and an individual’s propensity to work in a team is seen as a contributing factor in one’s personal learning. Research purpose: The purpose of this article is twofold. Firstly, the article aims to explore whether individual-level cultural values of power distance, uncertainty avoidance and masculinity–femininity interact with individual collectivist values to influence teamwork orientation. Secondly, the study aims to examine the influence of teamwork orientation on personal learning further exploring the role of perceived value congruence in this relationship. Motivation for the study: While an extensive amount of research has been conducted on teamwork orientation, the question of how individual cultural values influence formation of teamwork orientation is still largely unanswered. This lack is especially evident with regard to how the influence of collectivism on the development of positive attitudes towards teamwork is promoted or inhibited by other values such as power distance, uncertainty avoidance and masculinity–femininity. Moreover, the current evidence about the influence of teamwork orientation on personal learning and the role of personal and contextual factors in such a relationship is still scarce. Research design, approach and method: The study used a cross-sectional survey, with data collected from 120 business students engaged in project teams at a Norwegian university. All the hypothesised relationships were assessed using partial least square structural equation modelling technique. Main findings: The findings indicate that the link between collectivism–teamwork orientation is stronger for team members who scored high on uncertainty avoidance values and the relationship was weaker for team members who endorsed high

  18. Impact of eLearning Perception and eLearning Advantages on eLearning for Stress Management (Mediating Role of eLearning for Corporate Training)

    OpenAIRE

    Aamir Sarwar; Chitapa Ketavan; Nadeem Shafique Butt

    2015-01-01

    The objective of the study was to develop a model with and without the mediator comparing direct and indirect Impacts using Bootstrap (Two tailed significance results to be used), options for manufacturing, services sectors and overall and finding out the significance of the relationship. Study tried to find out the Impact of eLearning Perception and eLearning Advantages on eLearning for Stress Management with eLearning for Corporate Training as a mediator. This is a cross sectional study con...

  19. Exploring the roles of interaction and flow in explaining nurses' e-learning acceptance.

    Science.gov (United States)

    Cheng, Yung-Ming

    2013-01-01

    To provide safe and competent patient care, it is very important that medical institutions should provide nurses with continuing education by using appropriate learning methods. As compared to traditional learning, electronic learning (e-learning) is a more flexible method for nurses' in-service learning. Hence, e-learning is expected to play a pivotal role in providing continuing education for nurses. This study's purpose was to explore the role and relevance of interaction factors, intrinsic motivator (i.e., flow), and extrinsic motivators (i.e., perceived usefulness (PU) and perceived ease of use (PEOU)) in explaining nurses' intention to use the e-learning system. Based on the technology acceptance model (TAM) with the flow theory, this study's research model presents three types of interaction factors, learner-system interaction, instructor-learner interaction, and learner-learner interaction to construct an extended TAM to explore nurses' intention to use the e-learning system. Sample data were gathered from nurses at two regional hospitals in Taiwan. A total of 320 questionnaires were distributed, 254 (79.375%) questionnaires were returned. Consequently, 218 usable questionnaires were analyzed in this study, with a usable response rate of 68.125%. First, confirmatory factor analysis was used to develop the measurement model. Second, to explore the causal relationships among all constructs, the structural model for the research model was tested by using structural equation modeling. First, learner-system interaction, instructor-learner interaction, and learner-learner interaction respectively had significant effects on PU, PEOU, and flow. Next, flow had significant effects on PU and PEOU, and PEOU had a significant effect on PU. Finally, the effects of flow, PU, and PEOU on intention to use were significant. Synthetically speaking, learner-system interaction, instructor-learner interaction, and learner-learner interaction can indirectly make significant

  20. Role of defects in the carrier-tunable topological-insulator (Bi1 -xSbx )2Te3 thin films

    Science.gov (United States)

    Scipioni, Kane L.; Wang, Zhenyu; Maximenko, Yulia; Katmis, Ferhat; Steiner, Charlie; Madhavan, Vidya

    2018-03-01

    Alloys of Bi2Te3 and Sb2Te3[(Bi1-xSbx) 2Te3] have played an essential role in the exploration of topological surface states, allowing us to study phenomena that would otherwise be obscured by bulk contributions to conductivity. Despite intensive transport and angle resolved photoemission (ARPES) studies, important questions about this system remain unanswered. For example, previous studies reported the chemical tuning of the Fermi level to the Dirac point by controlling the Sb:Bi composition ratio, but the optimum ratio varies widely across various studies. Moreover, it is unclear how the quasiparticle lifetime is affected by the disorder resulting from Sb/Bi alloying. In this work, we use scanning tunneling microscopy and spectroscopy to study the electronic structure of epitaxially grown (Bi,Sb) 2Te3 thin films at the nanoscale. We study Landau levels (LLs) to determine the effect of disorder on the quasiparticle lifetime as well as the position of the Dirac point with respect to the Fermi energy. A plot of the LL peak widths shows that despite the intrinsic disorder, the quasiparticle lifetime is not significantly degraded. We further determine that the ideal Sb concentration to place the Fermi energy to within a few meV of the Dirac point is x ˜0.7 , but that postannealing temperatures can have a significant effect on the crystallinity and Fermi level position. Specifically, high postgrowth annealing temperature can result in better crystallinity and surface roughness, but also produces a larger Te defect density which adds n -type carriers. Finally, in combination with quasiparticle interference imaging, the dispersion is revealed over a large energy range above the Fermi energy, in a regime inaccessible to ARPES. Interestingly, the surface state dispersion for the x ˜0.7 sample shows great similarity to pristine Bi2Te3 . This work provides microscopic information on the role of disorder and composition in determining carrier concentration, surface state

  1. Organizational learning, entrepreneurial orientation, and the role of university engagement in SMEs

    OpenAIRE

    Dada, Lola; Fogg, Helen

    2016-01-01

    This article analyses the effect of entrepreneurial orientation (EO) on organizational learning (OL) in small and medium-sized enterprises (SMEs) and the role of business/university engagement on the relationship between these two constructs. A cross-sectional research design, drawing upon a postal questionnaire survey, was employed to collect data from a sample of 206 UK SMEs. The results obtained from both the regression and moderated regression analyses revealed that EO positively impacts ...

  2. Teacher's Role in Managing the Class During Teaching and Learning Process

    OpenAIRE

    Rindu, Ignatius; Ariyanti, Ariyanti

    2017-01-01

    The purpose of this research is to investigate teacher’s roles which used by the English teacher in managing the class during the teaching and learning process at SMP Advent Samarinda. The research methodology used is descriptive design with qualitative approach which is aimed to describe the real situation in the field. In collecting the data, the researcher used questionnaires, observation sheet, field note and interview guide as the instruments. Moreover, the research subject is an English...

  3. Exploring the Role of Peer Advice in Self-Regulated Learning: Metacognitive, Social, and Environmental Factors.

    Science.gov (United States)

    Rashid, Hanin; Lebeau, Robert; Saks, Norma; Cianciolo, Anna T; Artino, Anthony R; Shea, Judy A; Ten Cate, Olle

    2016-01-01

    This Conversation Starters article presents a selected research abstract from the 2016 Association of American Medical Colleges Northeast Region Group on Educational Affairs annual spring meeting. The abstract is paired with the integrative commentary of three experts who shared their thoughts stimulated by the pilot study. These thoughts explore the metacognitive, social, and environmental mechanisms whereby advice plays a role in self-regulated learning.

  4. Effects of gender and role selection in cooperative learning groups on science inquiry achievement

    Science.gov (United States)

    Affhalter, Maria Geralyn

    An action research project using science inquiry labs and cooperative learning groups examined the effects of same-gender and co-educational classrooms on science achievement and teacher-assigned or self-selected group roles on students' role preferences. Fifty-nine seventh grade students from a small rural school district participated in two inquiry labs in co-educational classrooms or in an all-female classroom, as determined by parents at the beginning of the academic year. Students were assigned to the same cooperative groups for the duration of the study. Pretests and posttests were administered for each inquiry-based science lab. Posttest assessments included questions for student reflection on role assignment and role preference. Instruction did not vary and a female science teacher taught all class sections. The same-gender classroom and co-ed classrooms produced similar science achievement scores on posttests. Students' cooperative group roles, whether teacher-assigned or self-selected, produced similar science achievement scores on posttests. Male and female students shared equally in favorable and unfavorable reactions to their group roles during the science inquiry labs. Reflections on the selection of the leader role revealed a need for females in co-ed groups to be "in charge". When reflecting on her favorite role of leader, one female student in a co-ed group stated, "I like to have people actually listen to me".

  5. Role of state-dependent learning in the cognitive effects of caffeine in mice.

    Science.gov (United States)

    Sanday, Leandro; Zanin, Karina A; Patti, Camilla L; Fernandes-Santos, Luciano; Oliveira, Larissa C; Longo, Beatriz M; Andersen, Monica L; Tufik, Sergio; Frussa-Filho, Roberto

    2013-08-01

    Caffeine is the most widely used psychoactive substance in the world and it is generally believed that it promotes beneficial effects on cognitive performance. However, there is also evidence suggesting that caffeine has inhibitory effects on learning and memory. Considering that caffeine may have anxiogenic effects, thus changing the emotional state of the subjects, state-dependent learning may play a role in caffeine-induced cognitive alterations. Mice were administered 20 mg/kg caffeine before training and/or before testing both in the plus-maze discriminative avoidance task (an animal model that concomitantly evaluates learning, memory, anxiety-like behaviour and general activity) and in the inhibitory avoidance task, a classic paradigm for evaluating memory in rodents. Pre-training caffeine administration did not modify learning, but produced an anxiogenic effect and impaired memory retention. While pre-test administration of caffeine did not modify retrieval on its own, the pre-test administration counteracted the memory deficit induced by the pre-training caffeine injection in both the plus-maze discriminative and inhibitory avoidance tasks. Our data demonstrate that caffeine-induced memory deficits are critically related to state-dependent learning, reinforcing the importance of considering the participation of state-dependency on the interpretation of the cognitive effects of caffeine. The possible participation of caffeine-induced anxiety alterations in state-dependent memory deficits is discussed.

  6. Focus of Attention in Children's Motor Learning: Examining the Role of Age and Working Memory.

    Science.gov (United States)

    Brocken, J E A; Kal, E C; van der Kamp, J

    2016-01-01

    The authors investigated the relative effectiveness of different attentional focus instructions on motor learning in primary school children. In addition, we explored whether the effect of attentional focus on motor learning was influenced by children's age and verbal working memory capacity. Novice 8-9-year old children (n = 30) and 11-12-year-old children (n = 30) practiced a golf putting task. For each age group, half the participants received instructions to focus (internally) on the swing of their arm, while the other half was instructed to focus (externally) on the swing of the club. Children's verbal working memory capacity was assessed with the Automated Working Memory Assessment. Consistent with many reports on adult's motor learning, children in the external groups demonstrated greater improvements in putting accuracy than children who practiced with an internal focus. This effect was similar across age groups. Verbal working memory capacity was not found to be predictive of motor learning, neither for children in the internal focus groups nor for children in the external focus groups. In conclusion, primary school children's motor learning is enhanced by external focus instructions compared to internal focus instructions. The purported modulatory roles of children's working memory, attentional capacity, or focus preferences require further investigation.

  7. The role of character positional frequency on Chinese word learning during natural reading.

    Directory of Open Access Journals (Sweden)

    Feifei Liang

    Full Text Available Readers' eye movements were recorded to examine the role of character positional frequency on Chinese lexical acquisition during reading and its possible modulation by word spacing. In Experiment 1, three types of pseudowords were constructed based on each character's positional frequency, providing congruent, incongruent, and no positional word segmentation information. Each pseudoword was embedded into two sets of sentences, for the learning and the test phases. In the learning phase, half the participants read sentences in word-spaced format, and half in unspaced format. In the test phase, all participants read sentences in unspaced format. The results showed an inhibitory effect of character positional frequency upon the efficiency of word learning when processing incongruent pseudowords both in the learning and test phase, and also showed facilitatory effect of word spacing in the learning phase, but not at test. Most importantly, these two characteristics exerted independent influences on word segmentation. In Experiment 2, three analogous types of pseudowords were created whilst controlling for orthographic neighborhood size. The results of the two experiments were consistent, except that the effect of character positional frequency was absent in the test phase in Experiment 2. We argue that the positional frequency of a word's constituent characters may influence the character-to-word assignment in a process that likely incorporates both lexical segmentation and identification.

  8. The dorsolateral periaqueductal gray and its role in mediating fear learning to life threatening events.

    Directory of Open Access Journals (Sweden)

    Grasielle C Kincheski

    Full Text Available The dorsolateral column of the periaqueductal gray (dlPAG integrates aversive emotional experiences and represents an important site responding to life threatening situations, such as hypoxia, cardiac pain and predator threats. Previous studies have shown that the dorsal PAG also supports fear learning; and we have currently explored how the dlPAG influences associative learning. We have first shown that N-methyl-D-aspartate (NMDA 100 pmol injection in the dlPAG works as a valuable unconditioned stimulus (US for the acquisition of olfactory fear conditioning (OFC using amyl acetate odor as conditioned stimulus (CS. Next, we revisited the ascending projections of the dlPAG to the thalamus and hypothalamus to reveal potential paths that could mediate associative learning during OFC. Accordingly, the most important ascending target of the dlPAG is the hypothalamic defensive circuit, and we were able to show that pharmacological inactivation using β-adrenoceptor blockade of the dorsal premammillary nucleus, the main exit way for the hypothalamic defensive circuit to thalamo-cortical circuits involved in fear learning, impaired the acquisition of the OFC promoted by NMDA stimulation of the dlPAG. Moreover, our tracing study revealed multiple parallel paths from the dlPAG to several thalamic targets linked to cortical-hippocampal-amygdalar circuits involved in fear learning. Overall, the results point to a major role of the dlPAG in the mediation of aversive associative learning via ascending projections to the medial hypothalamic defensive circuit, and perhaps, to other thalamic targets, as well. These results provide interesting perspectives to understand how life threatening events impact on fear learning, and should be useful to understand pathological fear memory encoding in anxiety disorders.

  9. Impact of eLearning Perception and eLearning Advantages on eLearning for Stress Management (Mediating Role of eLearning for Corporate Training

    Directory of Open Access Journals (Sweden)

    Aamir Sarwar

    2015-08-01

    Full Text Available The objective of the study was to develop a model with and without the mediator comparing direct and indirect Impacts using Bootstrap (Two tailed significance results to be used, options for manufacturing, services sectors and overall and finding out the significance of the relationship. Study tried to find out the Impact of eLearning Perception and eLearning Advantages on eLearning for Stress Management with eLearning for Corporate Training as a mediator. This is a cross sectional study conducted in Pakistan. Detailed questionnaire was used to collect the data. Total sample size of 686 includes 331 from manufacturing sector and 355 from services sector. Study revealed that overall eLearning for corporate training partially mediates relationship between eLearning Perception and elearning for stress management. However, in subgroup of manufacturing sector full mediation is observed. eLearning for corporate training partially mediates relationship between eLearning Advantages and Stress management training. Similar partial mediation is observed for subgroups of manufacturing and services sector. However in subgroup of manufacturing sector no mediation was observed.

  10. Facts about Birth Defects

    Science.gov (United States)

    ... label> Information For… Media Policy Makers Facts about Birth Defects Language: English (US) Español (Spanish) Recommend on ... having a baby born without a birth defect. Birth Defects Are Common Every 4 ½ minutes, a ...

  11. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...

  12. Exploring the Impact of Role-Playing on Peer Feedback in an Online Case-Based Learning Activity

    Science.gov (United States)

    Ching, Yu-Hui

    2014-01-01

    This study explored the impact of role-playing on the quality of peer feedback and learners' perception of this strategy in a case-based learning activity with VoiceThread in an online course. The findings revealed potential positive impact of role-playing on learners' generation of constructive feedback as role-playing was associated with higher…

  13. The role of multiple neuromodulators in reinforcement learning that is based on competition between eligibility traces

    Directory of Open Access Journals (Sweden)

    Marco A Huertas

    2016-12-01

    Full Text Available The ability to maximize reward and avoid punishment is essential for animal survival. Reinforcement learning (RL refers to the algorithms used by biological or artificial systems to learn how to maximize reward or avoid negative outcomes based on past experiences. While RL is also important in machine learning, the types of mechanistic constraints encountered by biological machinery might be different than those for artificial systems. Two major problems encountered by RL are how to relate a stimulus with a reinforcing signal that is delayed in time (temporal credit assignment, and how to stop learning once the target behaviors are attained (stopping rule. To address the first problem, synaptic eligibility traces were introduced, bridging the temporal gap between a stimulus and its reward. Although these were mere theoretical constructs, recent experiements have provided evidence of their existence. These experiments also reveal that the presence of specific neuromodulators converts the traces into changes in synaptic efficacy. A mechanistic implementation of the stopping rule usually assumes the inhibition of the reward nucleus; however, recent experimental results have shown that learning terminates at the appropriate network state even in setups where the reward cannot be inhibited. In an effort to describe a learning rule that solves the temporal credit assignment problem and implements a biologically plausible stopping rule, we proposed a model based on two separate synaptic eligibility traces, one for long-term potentiation (LTP and one for long-term depression (LTD, each obeying different dynamics and having different effective magnitudes. The model has been shown to successfully generate stable learning in recurrent networks. Although the model assumes the presence of a single neuromodulator, evidence indicates that there are different neuromodulators for expressing the different traces. What could be the role of different

  14. The Role of Multiple Neuromodulators in Reinforcement Learning That Is Based on Competition between Eligibility Traces.

    Science.gov (United States)

    Huertas, Marco A; Schwettmann, Sarah E; Shouval, Harel Z

    2016-01-01

    The ability to maximize reward and avoid punishment is essential for animal survival. Reinforcement learning (RL) refers to the algorithms used by biological or artificial systems to learn how to maximize reward or avoid negative outcomes based on past experiences. While RL is also important in machine learning, the types of mechanistic constraints encountered by biological machinery might be different than those for artificial systems. Two major problems encountered by RL are how to relate a stimulus with a reinforcing signal that is delayed in time (temporal credit assignment), and how to stop learning once the target behaviors are attained (stopping rule). To address the first problem synaptic eligibility traces were introduced, bridging the temporal gap between a stimulus and its reward. Although, these were mere theoretical constructs, recent experiments have provided evidence of their existence. These experiments also reveal that the presence of specific neuromodulators converts the traces into changes in synaptic efficacy. A mechanistic implementation of the stopping rule usually assumes the inhibition of the reward nucleus; however, recent experimental results have shown that learning terminates at the appropriate network state even in setups where the reward nucleus cannot be inhibited. In an effort to describe a learning rule that solves the temporal credit assignment problem and implements a biologically plausible stopping rule, we proposed a model based on two separate synaptic eligibility traces, one for long-term potentiation (LTP) and one for long-term depression (LTD), each obeying different dynamics and having different effective magnitudes. The model has been shown to successfully generate stable learning in recurrent networks. Although, the model assumes the presence of a single neuromodulator, evidence indicates that there are different neuromodulators for expressing the different traces. What could be the role of different neuromodulators for

  15. The Role of Three-Dimensional Scaffolds in Treating Long Bone Defects: Evidence from Preclinical and Clinical Literature-A Systematic Review.

    Science.gov (United States)

    Roffi, Alice; Krishnakumar, Gopal Shankar; Gostynska, Natalia; Kon, Elizaveta; Candrian, Christian; Filardo, Giuseppe

    2017-01-01

    Long bone defects represent a clinical challenge. Bone tissue engineering (BTE) has been developed to overcome problems associated with conventional methods. The aim of this study was to assess the BTE strategies available in preclinical and clinical settings and the current evidence supporting this approach. A systematic literature screening was performed on PubMed database, searching for both preclinical (only on large animals) and clinical studies. The following string was used: "(Scaffold OR Implant) AND (Long bone defect OR segmental bone defect OR large bone defect OR bone loss defect)." The search retrieved a total of 1573 articles: 51 preclinical and 4 clinical studies were included. The great amount of preclinical papers published over the past few years showed promising findings in terms of radiological and histological evidence. Unfortunately, this in vivo situation is not reflected by a corresponding clinical impact, with few published papers, highly heterogeneous and with small patient populations. Several aspects should be further investigated to translate positive preclinical findings into clinical protocols: the identification of the best biomaterial, with both biological and biomechanical suitable properties, and the selection of the best choice between cells, GFs, or their combination through standardized models to be validated by randomized trials.

  16. The roles of the olivocerebellar pathway in motor learning and motor control. A consensus paper

    Science.gov (United States)

    Lang, Eric J.; Apps, Richard; Bengtsson, Fredrik; Cerminara, Nadia L.; De Zeeuw, Chris I.; Ebner, Timothy J.; Heck, Detlef H.; Jaeger, Dieter; Jörntell, Henrik; Kawato, Mitsuo; Otis, Thomas S.; Ozyildirim, Ozgecan; Popa, Laurentiu S.; Reeves, Alexander M.B.; Schweighofer, Nicolas; Sugihara, Izumi; Xiao, Jianqiang

    2016-01-01

    For many decades the predominant view in the cerebellar field has been that the olivocerebellar system's primary function is to induce plasticity in the cerebellar cortex, specifically, at the parallel fiber-Purkinje cell synapse. However, it has also long been proposed that the olivocerebellar system participates directly in motor control by helping to shape ongoing motor commands being issued by the cerebellum. Evidence consistent with both hypotheses exists; however, they are often investigated as mutually exclusive alternatives. In contrast, here we take the perspective that the olivocerebellar system can contribute to both the motor learning and motor control functions of the cerebellum, and might also play a role in development. We then consider the potential problems and benefits of its having multiple functions. Moreover, we discuss how its distinctive characteristics (e.g., low firing rates, synchronization, variable complex spike waveform) make it more or less suitable for one or the other of these functions, and why its having a dual role makes sense from an evolutionary perspective. We did not attempt to reach a consensus on the specific role(s) the olivocerebellar system plays in different types of movements, as that will ultimately be determined experimentally; however, collectively, the various contributions highlight the flexibility of the olivocerebellar system, and thereby suggest it has the potential to act in both the motor learning and motor control functions of the cerebellum. PMID:27193702

  17. The making of a nurse manager: the role of experiential learning in leadership development.

    Science.gov (United States)

    Cathcart, Eloise Balasco; Greenspan, Miriam; Quin, Matthew

    2010-05-01

    To articulate the experientially acquired knowledge, skill and ethics embedded in nurse manager practice and describe the ways in which they were developed. The role of the nurse manager is usually described in lists of competencies, talents and traits which fail to capture the experience-based judgment and practical knowledge in this pivotal organizational role. Using Benner's methodology of practice articulation, 32 nurse managers wrote and interpreted first person narratives of their practice. The experience level of the group ranged from new nurse managers to those with more than 10 years' role tenure. The seminars were facilitated by a seasoned nurse executive and nurse manager with expertise in narrative interpretation. Interpretation of the paradigm case of one nurse manager suggests that complex leadership challenges can be a source of significant experiential learning for the individual and for the group. CONCLUSIONS; Articulating and reflecting on experiential learning elucidates the skilled knowledge and judgment embedded in nurse manager practice which cannot be accessed in any other way. Articulating the practical knowledge which is necessary for effective nurse manager practice can hasten the development of role incumbents.

  18. A kinetic Monte Carlo study on the role of defects and detachment in the formation and growth of In chains on Si(100)

    International Nuclear Information System (INIS)

    Albao, Marvin A; Chuang, F-C; Evans, J W

    2009-01-01

    Deposition on a Si(100) surface and subsequent self-assembly of In atoms into one-dimensional (1D) atomic chains at room temperature is investigated via kinetic Monte Carlo simulation of a suitable atomistic model. Model development is guided by recent experimental observations in which 1D In chains nucleate effectively exclusively at C-type defects, although In atoms can detach from chains. We find that a monotonically decreasing form of the scaled island size distribution (ISD) is consistent with a high defect density which facilitates persistent chain nucleation even at relatively high coverages. The predominance of heterogeneous nucleation may be attributed to several factors including low surface diffusion barriers, a high defect density, and relatively weak In-In binding.

  19. The role of critical thinking skills and learning styles of university students in their academic performance

    Directory of Open Access Journals (Sweden)

    ZOHRE GHAZIVAKILI

    2014-07-01

    Full Text Available Introduction: The current world needs people who have a lot of different abilities such as cognition and application of different ways of thinking, research, problem solving, critical thinking skills and creativity. In addition to critical thinking, learning styles is another key factor which has an essential role in the process of problem solving. This study aimed to determine the relationship between learning styles and critical thinking of students and their academic performance in Alborz University of Medical Sciences. Methods: This cross-correlation study was performed in 2012, on 216 students of Alborz University who were selected randomly by the stratified method. The data was obtained via a three-part questionnaire included demographic data, Kolb standardized questionnaire of learning style and California critical thinking standardized questionnaire. The academic performance of the students was extracted by the school records. The validity of the instruments was determined in terms of content validity, and the reliability was gained through internal consistency methods. Cronbach's alpha coefficient was found to be 0.78 for the California critical thinking questionnaire. The Chi Square test, Independent T-test, one way ANOVA and Pearson Correlation test were used to determine relationship between variables. The Package SPSS14 statistical software was used to analyze data with a significant level of p<0.05. Results: Our findings indicated the significant difference of mean score in four learning style, suggesting university students with convergent learning style have better performance than other groups. Also learning style had a relationship with age, gender, field of study, semester and job. The results about the critical thinking of the students showed that the mean of deductive reasoning and evaluation skills were higher than that of other skills and analytical skills had the lowest mean and there was a positive significant

  20. The Role Of The Integrated, Thematic Project To Learning Progress Of The Child In The Early Period

    Directory of Open Access Journals (Sweden)

    Aida Cornelia Stoian

    2016-12-01

    Full Text Available In this study, we have proposed to present you the results of an empirical research in order to identify the positive aspects of the integrated, thematic project in learning progress of children in preschool. Using the observation method, we analyzed children's results regarding the objectives in the respect to the objectives in the grid. Children's progress in learning represents the confirmation and affirmation of the role of this integrated, thematic project in supporting the early learning child.

  1. The role of experience-based perceptual learning in the face inversion effect.

    Science.gov (United States)

    Civile, Ciro; Obhi, Sukhvinder S; McLaren, I P L

    2018-04-03

    Perceptual learning of the type we consider here is a consequence of experience with a class of stimuli. It amounts to an enhanced ability to discriminate between stimuli. We argue that it contributes to the ability to distinguish between faces and recognize individuals, and in particular contributes to the face inversion effect (better recognition performance for upright vs inverted faces). Previously, we have shown that experience with a prototype defined category of checkerboards leads to perceptual learning, that this produces an inversion effect, and that this effect can be disrupted by Anodal tDCS to Fp3 during pre-exposure. If we can demonstrate that the same tDCS manipulation also disrupts the inversion effect for faces, then this will strengthen the claim that perceptual learning contributes to that effect. The important question, then, is whether this tDCS procedure would significantly reduce the inversion effect for faces; stimuli that we have lifelong expertise with and for which perceptual learning has already occurred. Consequently, in the experiment reported here we investigated the effects of anodal tDCS at Fp3 during an old/new recognition task for upright and inverted faces. Our results show that stimulation significantly reduced the face inversion effect compared to controls. The effect was one of reducing recognition performance for upright faces. This result is the first to show that tDCS affects perceptual learning that has already occurred, disrupting individuals' ability to recognize upright faces. It provides further support for our account of perceptual learning and its role as a key factor in face recognition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. The role of critical thinking skills and learning styles of university students in their academic performance

    Science.gov (United States)

    GHAZIVAKILI, ZOHRE; NOROUZI NIA, ROOHANGIZ; PANAHI, FARIDE; KARIMI, MEHRDAD; GHOLSORKHI, HAYEDE; AHMADI, ZARRIN

    2014-01-01

    Introduction: The Current world needs people who have a lot of different abilities such as cognition and application of different ways of thinking, research, problem solving, critical thinking skills and creativity. In addition to critical thinking, learning styles is another key factor which has an essential role in the process of problem solving. This study aimed to determine the relationship between learning styles and critical thinking of students and their academic performance in Alborz University of Medical Science. Methods: This cross-correlation study was performed in 2012, on 216 students of Alborz University who were selected randomly by the stratified random sampling. The data was obtained via a three-part questionnaire included demographic data, Kolb standardized questionnaire of learning style and California critical thinking standardized questionnaire. The academic performance of the students was extracted by the school records. The validity of the instruments was determined in terms of content validity, and the reliability was gained through internal consistency methods. Cronbach's alpha coefficient was found to be 0.78 for the California critical thinking questionnaire. The Chi Square test, Independent t-test, one way ANOVA and Pearson correlation test were used to determine relationship between variables. The Package SPSS14 statistical software was used to analyze data with a significant level of pcritical thinking of the students showed that the mean of deductive reasoning and evaluation skills were higher than that of other skills and analytical skills had the lowest mean and there was a positive significant relationship between the students’ performance with inferential skill and the total score of critical thinking skills (pcritical thinking had significant difference between different learning styles. Conclusion: The results of this study showed that the learning styles, critical thinking and academic performance are significantly associated

  3. Theory of Defects in Semiconductors

    CERN Document Server

    Drabold, David A

    2007-01-01

    Semiconductor science and technology is the art of defect engineering. The theoretical modeling of defects has improved dramatically over the past decade. These tools are now applied to a wide range of materials issues: quantum dots, buckyballs, spintronics, interfaces, amorphous systems, and many others. This volume presents a coherent and detailed description of the field, and brings together leaders in theoretical research. Today's state-of-the-art, as well as tomorrow’s tools, are discussed: the supercell-pseudopotential method, the GW formalism,Quantum Monte Carlo, learn-on-the-fly molecular dynamics, finite-temperature treatments, etc. A wealth of applications are included, from point defects to wafer bonding or the propagation of dislocation.

  4. Developing pharmacy student communication skills through role-playing and active learning.

    Science.gov (United States)

    Luiz Adrian, Julie Ann; Zeszotarski, Paula; Ma, Carolyn

    2015-04-25

    To evaluate the impact on pharmacy students of a communication course, which used role-playing to develop active-learning skills. Students role-playing pharmacists in patient care scenarios were critiqued by students and pharmacist faculty members. Grading was performed using the rubric inspired by Bruce Berger's Communication Skills for Pharmacists. Written skills were evaluated using student written critique questionnaires. Students completed precourse and postcourse self-assessment surveys. Preceptor evaluations were analyzed for course impact. Students demonstrated improvement in oral skills based on role-play scores (45.87/50) after practice sessions. The average score based on the student questionnaire was 9.31/10. Gain was demonstrated in all defined course objectives. Impact on introductory pharmacy practice experience (IPPE) communication objectives was insignificant. Student evaluations for course and teaching strategy reflected a high average. Study results demonstrated improvement in oral and written communication skills that may help improve interprofessional teamwork between pharmacists and other health care providers.

  5. Work-based learning and role extension: A match made in heaven?

    International Nuclear Information System (INIS)

    Eddy, Angela

    2010-01-01

    This paper presents, and discusses the findings from an exploratory study which examined a cohort of postgraduate therapeutic radiographer students' experiences of undertaking work-based learning to support role extension. The findings showed that three themes emerged which impacted on individual experiences: organisational issues, role and practice issues related to competence development and the individual's background and experience. The conclusions are that new models must emerge, and be evaluated, to offer appropriate support to those individuals who demonstrate the skills and ability to progress to advanced and consultant levels. Departments need to deliberate how they can effectively introduce and support role extension, giving specific consideration to study time, the number of higher level practitioners in training, as well as how to offer effective clinical supervision. Collaboration between higher education institutes and departments should enable the development of tripartite agreements to facilitate effective support for the learners.

  6. The Role of Work-Integrated Learning in Student Preferences of Instructional Methods in an Accounting Curriculum

    Science.gov (United States)

    Abeysekera, Indra

    2015-01-01

    The role of work-integrated learning in student preferences of instructional methods is largely unexplored across the accounting curriculum. This study conducted six experiments to explore student preferences of instructional methods for learning, in six courses of the accounting curriculum that differed in algorithmic rigor, in the context of a…

  7. "You Have to Get Hit a Couple of Times": The Role of Conflict in Learning How to "Be" a Skateboarder

    Science.gov (United States)

    Petrone, Robert

    2010-01-01

    By examining the role of conflict in learning how to "be" a skateboarder at a skate park in the United States, this article illustrates how conflicts constitute key aspects of learning and teaching within communities of practice. Specifically, this article demonstrates how the practices of "snaking" and "heckling" are used by a group of…

  8. Harnessing members' positive mood for team-directed learning behaviour and team innovation : The moderating role of perceived team feedback

    NARCIS (Netherlands)

    Walter, Frank; van der Vegt, Gerben S.

    2013-01-01

    This study examines the role of individual team members' positive mood and perceived team feedback for their team-directed learning behaviour. Results obtained in a sample of 186 members from 27 work teams showed that positive mood was positively associated with team-directed learning behaviour if

  9. University Student and Teacher Perceptions of Teacher Roles in Promoting Autonomous Language Learning with Technology outside the Classroom

    Science.gov (United States)

    Lai, Chun; Yeung, Yuk; Hu, Jingjing

    2016-01-01

    Helping students to become autonomous learners, who actively utilize technologies for learning outside the classroom, is important for successful language learning. Teachers, as significant social agents who shape students' intellectual and social experiences, have a critical role to play. This study examined students' and teachers' perceptions of…

  10. The Role of Transformational Leadership, Organizational Culture and Organizational Learning in Improving the Performance of Iranian Agricultural Faculties

    Science.gov (United States)

    Abbasi, Enayat; Zamani-Miandashti, Naser

    2013-01-01

    This empirical research was conducted to investigate the role of transformational leadership, organizational culture and organizational learning in improving the performance of Iranian agricultural faculties and leading them to become learning organizations. The research population consisted of all faculty members of public agricultural faculties…

  11. On the Role of Discipline-Related Self-Concept in Deep and Surface Approaches to Learning among University Students

    Science.gov (United States)

    Platow, Michael J.; Mavor, Kenneth I.; Grace, Diana M.

    2013-01-01

    The current research examined the role that students' discipline-related self-concepts may play in their deep and surface approaches to learning, their overall learning outcomes, and continued engagement in the discipline itself. Using a cross-lagged panel design of first-year university psychology students, a causal path was observed in which…

  12. Nonstoichiometric defects in GaAs and the EL2 bandwagon

    Science.gov (United States)

    Lagowski, J.; Gatos, H. C.

    1985-09-01

    In the present paper, an attempt is made to formulate a common framework for a discussion of nonstoichiometric defects, especially EL2 and dislocations. An outline is provided of the most important settled and unsettled issues, taking into account not only fundamental interests, but also urgent needs in advancing IC technology. Attention is given to stoichiometry-controlled compensation, the expected role of melt stoichiometry in electrical conductivity for the basic atomic disorders, defect equilibria-dislocations and EL2, and current issues pertaining to the identification of EL2. It is concluded that nonstoichiometric defects play a critical role in the electronic properties of GaAs and its electronic applications. Very significant progress has been recently made in learning how to adjust melt stoichiometry in order to maximize its beneficial effects and minimize its detrimental ones.

  13. An investigation of the role of background music in IVWs for learning

    Directory of Open Access Journals (Sweden)

    Debbie Richards

    2008-12-01

    Full Text Available Empirical evidence is needed to corroborate the intuitions of gamers and game developers in understanding the benefits of Immersive Virtual Worlds (IVWs as a learning environment and the role that music plays within these environments. We report an investigation to determine if background music of the genre typically found in computer-based role-playing games has an effect on learning in a computer-animated history lesson about the Macquarie Lighthouse within an IVW. In Experiment 1, music stimuli were created from four different computer game soundtracks. Seventy-two undergraduate students watched the presentation and completed a survey including biographical details, questions on the historical material presented and questions relating to their perceived level of immersion. While the tempo and pitch of the music was unrelated to learning, music conditions resulted in a higher number of accurately remembered facts than the no music condition. One soundtrack showed a statistically significant improvement in memorisation of facts over other music conditions. Also an interaction between the levels of perceived immersion and ability to accurately remember facts was observed. Experiment 2, involving 48 undergraduate students, further investigated the effect of music, sense of immersion and how different display systems affect memory for facts.

  14. Role of σ1 Receptors in Learning and Memory and Alzheimer's Disease-Type Dementia.

    Science.gov (United States)

    Maurice, Tangui; Goguadze, Nino

    2017-01-01

    The present chapter will review the role of σ 1 receptor in learning and memory and neuroprotection , against Alzheimer's type dementia. σ 1 Receptor agonists have been tested in a variety of pharmacological and pathological models of learning impairments in rodents these last past 20 years. Their anti-amnesic effects have been explained by the wide-range modulatory role of σ 1 receptors on Ca 2+ mobilizations, neurotransmitter responses, and particularly glutamate and acetylcholine systems, and neurotrophic factors. Recent observations from genetic and pharmacological studies have shown that σ 1 receptor can also be targeted in neurodegenerative diseases, and particularly Alzheimer's disease . Several compounds, acting partly through the σ 1 receptor, have showed effective neuroprotection in transgenic mouse models of Alzheimer's disease . We will review the data and discuss the possible mechanisms of action, particularly focusing on oxidative stress and mitochondrial integrity, trophic factors and a novel hypothesis suggesting a functional interaction between the σ 1 receptor and α 7 nicotinic acetylcholine receptor. Finally, we will discuss the pharmacological peculiarities of non-selective σ 1 receptor ligands, now developed as neuroprotectants in Alzheimer's disease , and positive modulators, recently described and that showed efficacy against learning and memory deficits.

  15. Beyond Construction: Five arguments for the role and value of critique in learning science

    Science.gov (United States)

    Henderson, J. Bryan; MacPherson, Anna; Osborne, Jonathan; Wild, Andrew

    2015-07-01

    This paper argues that science education has overemphasized the importance of construction at the expense of critique. In doing so, it draws on two key premises-Ford's argument that the construction of knowledge requires a dialectic between construction and critique and Mercier and Sperber's theory of argumentative reasoning that critique is essential for epistemic vigilance. Five separate cases are presented which argue that the absence of critique within school science limits the opportunities for students to engage in scientific reasoning making the learning of science less effective. These five arguments incorporate research literature surrounding the nature of science, epistemology, literacy, pedagogy, and motivation. Furthermore, we draw on data collected from cognitive think-aloud interviews to show that students can, with the appropriate prompts, engage in the important epistemic activity of critique. We conclude by examining the implications for the teaching and learning of science. In essence, we argue that the undervaluing of critique within the curriculum and pedagogy of school science results in a failure to develop the analytical faculties which are the valued hall mark of the practicing scientist; a misrepresentation of the nature of science; and, more importantly, a less effective learning experience. Critique, therefore, needs to play a central role in the teaching and learning of science.

  16. Rule-based category learning in children: the role of age and executive functioning.

    Directory of Open Access Journals (Sweden)

    Rahel Rabi

    Full Text Available Rule-based category learning was examined in 4-11 year-olds and adults. Participants were asked to learn a set of novel perceptual categories in a classification learning task. Categorization performance improved with age, with younger children showing the strongest rule-based deficit relative to older children and adults. Model-based analyses provided insight regarding the type of strategy being used to solve the categorization task, demonstrating that the use of the task appropriate strategy increased with age. When children and adults who identified the correct categorization rule were compared, the performance deficit was no longer evident. Executive functions were also measured. While both working memory and inhibitory control were related to rule-based categorization and improved with age, working memory specifically was found to marginally mediate the age-related improvements in categorization. When analyses focused only on the sample of children, results showed that working memory ability and inhibitory control were associated with categorization performance and strategy use. The current findings track changes in categorization performance across childhood, demonstrating at which points performance begins to mature and resemble that of adults. Additionally, findings highlight the potential role that working memory and inhibitory control may play in rule-based category learning.

  17. The Role of Consulting a Dictionary in Reading and Vocabulary Learning

    Directory of Open Access Journals (Sweden)

    Carol A. Fraser

    1999-12-01

    Full Text Available Abstract This article reviews recent research on consulting a dictionary in L2 reading and vocabulary learning. From the perspective of cognitive learning theory, the author re-evaluates the limited role that has often been accorded to dictionary consulting. It is noted that, among the three available lexical processing strategies (inferencing, consulting and ignoring, learners tend to use consulting infrequently and selectively and also to differ among each other in their strategy use. Consulting in combination with inferencing is shown to have the greatest positive effect on performance in L2 reading and vocabulary learning, although consulting is found to slow down task completion. Excerpts from think-aloud protocols illustrate the potential contribution of strategic dictionary use to the cognitive processes required for vocabulary acquisition: attention to form-meaning connections, rehearsal of words for storage in long-term memory and elaboration of associations with other knowledge. Among the pedagogical implications of these findings is the need for training in lexical processing strategies in order to help learners use the dictionary effectively and accurately in L2 reading comprehension and vocabulary learning.

  18. Role of the area postrema in radiation-induced taste aversion learning and emesis in cats

    International Nuclear Information System (INIS)

    Rabin, B.M.; Hunt, W.A.; Chedester, A.L.; Lee, J.

    1986-01-01

    The role of the area postrema in radiation-induced emesis and taste aversion learning and the relationship between these behaviors were studied in cats. The potential involvement of neural factors which might be independent of the area postrema was minimized by using low levels of ionizing radiation (100 rads at a dose rate of 40 rads/min) to elicit a taste aversion, and by using body-only exposures (4500 and 6000 rads at 450 rads/min) to produce emesis. Lesions of the area postrema disrupted both taste aversion learning and emesis following irradiation. These results, which indicate that the area postrema is involved in the mediation of both radiation-induced emesis and taste aversion learning in cats under these experimental conditions, are interpreted as being consistent with the hypotheses that similar mechanisms mediate both responses to exposure to ionizing radiation, and that the taste aversion learning paradigm can therefore serve as a model system for studying radiation-induced emesis

  19. More Than Words: The Role of Multiword Sequences in Language Learning and Use.

    Science.gov (United States)

    Christiansen, Morten H; Arnon, Inbal

    2017-07-01

    The ability to convey our thoughts using an infinite number of linguistic expressions is one of the hallmarks of human language. Understanding the nature of the psychological mechanisms and representations that give rise to this unique productivity is a fundamental goal for the cognitive sciences. A long-standing hypothesis is that single words and rules form the basic building blocks of linguistic productivity, with multiword sequences being treated as units only in peripheral cases such as idioms. The new millennium, however, has seen a shift toward construing multiword linguistic units not as linguistic rarities, but as important building blocks for language acquisition and processing. This shift-which originated within theoretical approaches that emphasize language learning and use-has far-reaching implications for theories of language representation, processing, and acquisition. Incorporating multiword units as integral building blocks blurs the distinction between grammar and lexicon; calls for models of production and comprehension that can accommodate and give rise to the effect of multiword information on processing; and highlights the importance of such units to learning. In this special topic, we bring together cutting-edge work on multiword sequences in theoretical linguistics, first-language acquisition, psycholinguistics, computational modeling, and second-language learning to present a comprehensive overview of the prominence and importance of such units in language, their possible role in explaining differences between first- and second-language learning, and the challenges the combined findings pose for theories of language. Copyright © 2017 Cognitive Science Society, Inc.

  20. The Role of the Constructivist Learning Theory and Collaborative Learning Environment on Wiki Classroom, and the Relationship between Them

    Science.gov (United States)

    Alzahrani, Ibraheem; Woollard, John

    2013-01-01

    This paper seeks to discover the relationship between both the social constructivist learning theory and the collaborative learning environment. This relationship can be identified by giving an example of the learning environment. Due to wiki characteristics, Wiki technology is one of the most famous learning environments that can show the…

  1. The Role of Mother Tongue Literacy in Language Learning and Mathematical Learning: Is There a Multilingual Benefit for Both?

    Science.gov (United States)

    Dahm, Rebecca; De Angelis, Gessica

    2018-01-01

    The present study examines the multilingual benefit in relation to language learning and mathematical learning. The objective is to assess whether speakers of three or more languages, depending on language profile and personal histories, show significant advantages in language learning and/or mathematical learning, and whether mother tongue…

  2. Fully Ab-Initio Determination of the Thermoelectric Properties of Half-Heusler NiTiSn: Crucial Role of Interstitial Ni Defects.

    Science.gov (United States)

    Berche, Alexandre; Jund, Philippe

    2018-05-23

    For thermoelectric applications, ab initio methods generally fail to predict the transport properties of the materials because of their inability to predict properly the carrier concentrations that control the electronic properties. In this work, a methodology to fill in this gap is applied on the NiTiSn half Heusler phase. For that, we show that the main defects act as donor of electrons and are responsible of the electronic properties of the material. Indeed, the presence of Ni i interstitial defects explains the experimental valence band spectrum and its associated band gap reported in the literature. Moreover, combining the DOS of the solid solutions with the determination of the energy of formation of charged defects, we show that Ni i defects are also responsible of the measured carrier concentration in experimentally supposed "pure" NiTiSn compounds. Subsequently the thermoelectric properties of NiTiSn can be calculated using a fully ab initio description and an overall correct agreement with experiments is obtained. This methodology can be extended to predict the result of extrinsic doping and thus to select the most efficient dopant for specific thermoelectric applications.

  3. The role of critical thinking skills and learning styles of university students in their academic performance.

    Science.gov (United States)

    Ghazivakili, Zohre; Norouzi Nia, Roohangiz; Panahi, Faride; Karimi, Mehrdad; Gholsorkhi, Hayede; Ahmadi, Zarrin

    2014-07-01

    The Current world needs people who have a lot of different abilities such as cognition and application of different ways of thinking, research, problem solving, critical thinking skills and creativity. In addition to critical thinking, learning styles is another key factor which has an essential role in the process of problem solving. This study aimed to determine the relationship between learning styles and critical thinking of students and their academic performance in Alborz University of Medical Science. This cross-correlation study was performed in 2012, on 216 students of Alborz University who were selected randomly by the stratified random sampling. The data was obtained via a three-part questionnaire included demographic data, Kolb standardized questionnaire of learning style and California critical thinking standardized questionnaire. The academic performance of the students was extracted by the school records. The validity of the instruments was determined in terms of content validity, and the reliability was gained through internal consistency methods. Cronbach's alpha coefficient was found to be 0.78 for the California critical thinking questionnaire. The Chi Square test, Independent t-test, one way ANOVA and Pearson correlation test were used to determine relationship between variables. The Package SPSS14 statistical software was used to analyze data with a significant level of pstudents with convergent learning style have better performance than other groups. Also learning style had a relationship with age, gender, field of study, semester and job. The results about the critical thinking of the students showed that the mean of deductive reasoning and evaluation skills were higher than that of other skills and analytical skills had the lowest mean and there was a positive significant relationship between the students' performance with inferential skill and the total score of critical thinking skills (pskills and deductive reasoning had significant

  4. Implicit learning in transient global amnesia and the role of stress

    Directory of Open Access Journals (Sweden)

    Frauke Nees

    2016-11-01

    with non-significant ratings of all parameters. Concerning brain activation patterns after the control procedure, controls showed increased hippocampal response during acquisition after the control procedure. This was not seen after stress exposure. In TGA patients, we observed an increased response in the right ventral striatum in the acquisition phase following stress. These findings suggest that alterations in implicit learning processes, including impaired hippocampal and increased striatal responses, might play a role in TGA pathophysiology, partly related to acute stress.

  5. A specific implicit sequence learning deficit as an underlying cause of dyslexia? Investigating the role of attention in implicit learning tasks.

    Science.gov (United States)

    Staels, Eva; Van den Broeck, Wim

    2017-05-01

    Recently, a general implicit sequence learning deficit was proposed as an underlying cause of dyslexia. This new hypothesis was investigated in the present study by including a number of methodological improvements, for example, the inclusion of appropriate control conditions. The second goal of the study was to explore the role of attentional functioning in implicit and explicit learning tasks. In a 2 × 2 within-subjects design 4 tasks were administered in 30 dyslexic and 38 control children: an implicit and explicit serial reaction time (RT) task and an implicit and explicit contextual cueing task. Attentional functioning was also administered. The entire learning curves of all tasks were analyzed using latent growth curve modeling in order to compare performances between groups and to examine the role of attentional functioning on the learning curves. The amount of implicit learning was similar for both groups. However, the dyslexic group showed slower RTs throughout the entire task. This group difference reduced and became nonsignificant after controlling for attentional functioning. Both implicit learning tasks, but none of the explicit learning tasks, were significantly affected by attentional functioning. Dyslexic children do not suffer from a specific implicit sequence learning deficit. The slower RTs of the dyslexic children throughout the entire implicit sequence learning process are caused by their comorbid attention problems and overall slowness. A key finding of the present study is that, in contrast to what was assumed for a long time, implicit learning relies on attentional resources, perhaps even more than explicit learning does. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Financial literacy among Turkish college students: the role of formal education, learning approaches, and parental teaching.

    Science.gov (United States)

    Akben-Selcuk, Elif; Altiok-Yilmaz, Ayse

    2014-10-01

    This study assessed financial literacy and its correlates among Turkish college students, with special emphasis on the role of formal education, learning approaches, and parental influences. Financial literacy was measured by the College Student Financial Literacy Survey, which assesses knowledge in four areas: general financial management, saving and borrowing, insurance, and investing. 853 Turkish university students were administered the survey (416 men, 437 women; M age = 20.3 yr., SD = 0.6). The mean percentage of correct responses was 45% (SD = 12.8%). Regression results showed that formal finance education in college, a deep approach to learning, and direct financial teaching by parents were significantly associated with higher financial literacy scores.

  7. Teachers' Understanding of the Role of Executive Functions in Mathematics Learning.

    Science.gov (United States)

    Gilmore, Camilla; Cragg, Lucy

    2014-09-01

    Cognitive psychology research has suggested an important role for executive functions, the set of skills that monitor and control thought and action, in learning mathematics. However, there is currently little evidence about whether teachers are aware of the importance of these skills and, if so, how they come by this information. We conducted an online survey of teachers' views on the importance of a range of skills for mathematics learning. Teachers rated executive function skills, and in particular inhibition and shifting, to be important for mathematics. The value placed on executive function skills increased with increasing teaching experience. Most teachers reported that they were aware of these skills, although few knew the term "executive functions." This awareness had come about through their teaching experience rather than from formal instruction. Researchers and teacher educators could do more to highlight the importance of these skills to trainee or new teachers.

  8. The Role of CLEAR Thinking in Learning Science from Multiple-Document Inquiry Tasks

    Directory of Open Access Journals (Sweden)

    Thomas D. GRIFFIN

    2012-10-01

    Full Text Available The main goal for the current study was to investigate whether individual differences in domaingeneral thinking dispositions might affect learning from multiple-document inquiry tasks in science.Middle school students were given a set of documents and were tasked with understanding how and why recent patterns in global temperature might be different from what has been observed in the past from those documents. Understanding was assessed with two measures: an essay task and an inference verification task. Domain-general thinking dispositions were assessed with a Commitment to Logic, Evidence, and Reasoning (CLEAR thinking scale. The measures of understanding wereuniquely predicted by both reading skills and CLEAR thinking scores, and these effects were not attributable to prior knowledge or interest. The results suggest independent roles for thinkingdispositions and reading ability when students read to learn from multiple-document inquiry tasks in science.

  9. The role of visualization in learning from computer-based images

    Science.gov (United States)

    Piburn, Michael D.; Reynolds, Stephen J.; McAuliffe, Carla; Leedy, Debra E.; Birk, James P.; Johnson, Julia K.

    2005-05-01

    Among the sciences, the practice of geology is especially visual. To assess the role of spatial ability in learning geology, we designed an experiment using: (1) web-based versions of spatial visualization tests, (2) a geospatial test, and (3) multimedia instructional modules built around QuickTime Virtual Reality movies. Students in control and experimental sections were administered measures of spatial orientation and visualization, as well as a content-based geospatial examination. All subjects improved significantly in their scores on spatial visualization and the geospatial examination. There was no change in their scores on spatial orientation. A three-way analysis of variance, with the geospatial examination as the dependent variable, revealed significant main effects favoring the experimental group and a significant interaction between treatment and gender. These results demonstrate that spatial ability can be improved through instruction, that learning of geological content will improve as a result, and that differences in performance between the genders can be eliminated.

  10. Teachers' Understanding of the Role of Executive Functions in Mathematics Learning

    Science.gov (United States)

    Gilmore, Camilla; Cragg, Lucy

    2014-01-01

    Cognitive psychology research has suggested an important role for executive functions, the set of skills that monitor and control thought and action, in learning mathematics. However, there is currently little evidence about whether teachers are aware of the importance of these skills and, if so, how they come by this information. We conducted an online survey of teachers' views on the importance of a range of skills for mathematics learning. Teachers rated executive function skills, and in particular inhibition and shifting, to be important for mathematics. The value placed on executive function skills increased with increasing teaching experience. Most teachers reported that they were aware of these skills, although few knew the term “executive functions.” This awareness had come about through their teaching experience rather than from formal instruction. Researchers and teacher educators could do more to highlight the importance of these skills to trainee or new teachers. PMID:25674156

  11. The role of plastic changes in the motor cortex and spinal cord for motor learning

    DEFF Research Database (Denmark)

    Nielsen, Jens Bo; Lundbye-Jensen, Jesper

    2010-01-01

    Adaptive changes of the efficacy of neural circuitries at different sites of the central nervous system is the basis of acquisition of new motor skills. Non-invasive human imaging and electrophysiological experiments have demonstrated that the primary motor cortex and spinal cord circuitries...... are key players in the early stages of skill acquisition and consolidation of motor learning. Expansion of the cortical representation of the trained muscles, changes in corticomuscular coupling and changes in stretch reflex activity are thus all markers of neuroplastic changes accompanying early skill...... acquisition. We have shown in recent experiments that sensory feedback from the active muscles play a surprisingly specific role at this stage of learning. Following motor skill training, repeated activation of sensory afferents from the muscle that has been involved in a previous training session, interfered...

  12. Research Into the Role of Students’ Affective Domain While Learning Geology in Field Environments

    Science.gov (United States)

    Elkins, J.

    2009-12-01

    Existing research programs in field-based geocognition include assessment of cognitive, psychomotor, and affective domains. Assessment of the affective domain often involves the use of instruments and techniques uncommon to the geosciences. Research regarding the affective domain also commonly results in the collection and production of qualitative data that is difficult for geoscientists to analyze due to their lack of familiarity with these data sets. However, important information about students’ affective responses to learning in field environments can be obtained by using these methods. My research program focuses on data produced by students’ affective responses to field-based learning environments, primarily among students at the introductory level. For this research I developed a Likert-scale Novelty Space Survey, which presents student ‘novelty space’ (Orion and Hofstien, 1993) as a polygon; the larger the polygons, the more novelty students are experiencing. The axises for these polygons correspond to novelty domains involving geographic, social, cognitive, and psychological factors. In addition to the Novelty Space Survey, data which I have collected/generated includes focus group interviews on the role of recreational experiences in geology field programs. I have also collected data concerning the motivating factors that cause students to take photographs on field trips. The results of these studies give insight to the emotional responses students have to learning in the field and are important considerations for practitioners of teaching in these environments. Collaborative investigations among research programs that cross university departments and include multiple institutions is critical at this point in development of geocognition as a field due to unfamiliarity with cognitive science methodology by practitioners teaching geosciences and the dynamic nature of field work by cognitive scientists. However, combining the efforts of cognitive

  13. Role of Pre-Course Student Characteristics on Student Learning in Interactive Teaching Environments

    Science.gov (United States)

    Miller, Kelly Anne

    The goal of this dissertation is to broaden our understanding of interactive teaching strategies, in the context of the introductory physics classroom at the undergraduate level. The dissertation is divided into four main projects, each of which investigates a specific aspect of teaching physics interactively. All four projects look towards improving the effectiveness of interactive teaching by understanding how pre-course student characteristics affect the way students learn interactively. We first discuss lecture demonstrations in the context of an interactive classroom using Peer Instruction. We study the role of predictions in conceptual learning. We examine how students' predictions affect what they report having seen during a demonstration. We also examine how student predictions affect what they recall as the outcome of the demonstration at the end of the semester. We then analyze student response patterns to conceptual questions posed during Peer Instruction. We look at the relationship between a student's tendency to switch their answer and pre-course student characteristics like science self-efficacy. Next we elucidate response timing to conceptual questions posed over the course of the semester, in two introductory physics classes taught using Peer Instruction. We look at the relationship between student response times and student characteristics like pre-course physics knowledge, science self-efficacy and gender. We study response times as a way of gaining insight into students thinking in Peer Instruction environments as well as to improve the implementation of Peer Instruction. Finally, we present work on the role of NB, an online collaborative textbook annotation tool, in a flipped, project based, physics class. We analyze the relationship between students' level of online engagement and traditional learning metrics to understand the effectiveness of NB in the context of flipped classrooms. We also report the results of experiments conducted to

  14. Developmental changes in children's normative reasoning across learning contexts and collaborative roles.

    Science.gov (United States)

    Riggs, Anne E; Young, Andrew G

    2016-08-01

    What influences children's normative judgments of conventional rules at different points in development? The current study explored the effects of two contextual factors on children's normative reasoning: the way in which the rules were learned and whether the rules apply to the self or others. Peer dyads practiced a novel collaborative board game comprising two complementary roles. Dyads were either taught both the prescriptive (i.e., what to do) and proscriptive (i.e., what not to do) forms of the rules, taught only the prescriptive form of the rules, or created the rules themselves. Children then judged whether third parties were violating or conforming to the rules governing their own roles and their partner's roles. Early school-aged children's (6- to 7-year-olds; N = 60) normative judgments were strongest when they had been taught the rules (with or without the proscriptive form), but were more flexible for rules they created themselves. Preschool-aged children's (4- to 5-year-olds; N = 60) normative judgments, however, were strongest when they were taught both the prescriptive and proscriptive forms of the rules. Additionally, preschoolers exhibited stronger normative judgments when the rules governed their own roles rather than their partner's roles, whereas school-aged children treated all rules as equally normative. These results demonstrate that children's normative reasoning is contingent on contextual factors of the learning environment and, moreover, highlight 2 specific areas in which children's inferences about the normativity of conventions strengthen over development. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. ESL students learning biology: The role of language and social interactions

    Science.gov (United States)

    Jaipal, Kamini

    This study explored three aspects related to ESL students in a mainstream grade 11 biology classroom: (1) the nature of students' participation in classroom activities, (2) the factors that enhanced or constrained ESL students' engagement in social interactions, and (3) the role of language in the learning of science. Ten ESL students were observed over an eight-month period in this biology classroom. Data were collected using qualitative research methods such as participant observation, audio-recordings of lessons, field notes, semi-structured interviews, short lesson recall interviews and students' written work. The study was framed within sociocultural perspectives, particularly the social constructivist perspectives of Vygotsky (1962, 1978) and Wertsch (1991). Data were analysed with respect to the three research aspects. Firstly, the findings showed that ESL students' preferred and exhibited a variety of participation practices that ranged from personal-individual to socio-interactive in nature. Both personal-individual and socio-interactive practices appeared to support science and language learning. Secondly, the findings indicated that ESL students' engagement in classroom social interactions was most likely influenced by the complex interactions between a number of competing factors at the individual, interpersonal and community/cultural levels (Rogoff, Radziszewska, & Masiello, 1995). In this study, six factors that appeared to enhance or constrain ESL students' engagement in classroom social interactions were identified. These factors were socio-cultural factors, prior classroom practice, teaching practices, affective factors, English language proficiency, and participation in the research project. Thirdly, the findings indicated that language played a significant mediational role in ESL students' learning of science. The data revealed that the learning of science terms and concepts can be explained by a functional model of language that includes: (1

  16. A critical role of glutamate transporter type 3 in the learning and memory of mice.

    Science.gov (United States)

    Wang, Zhi; Park, Sang-Hon; Zhao, Huijuan; Peng, Shuling; Zuo, Zhiyi

    2014-10-01

    Hippocampus-dependent learning and memory are associated with trafficking of excitatory amino acid transporter type 3 (EAAT3) to the plasma membrane. To assess whether this trafficking is an intrinsic component of the biochemical responses underlying learning and memory, 7- to 9-week old male EAAT3 knockout mice and CD-1 wild-type mice were subjected to fear conditioning. Their hippocampal CA1 regions, amygdalae and entorhinal cortices were harvested before, or 30 min or 3 h after the fear conditioning stimulation. We found that EAAT3 knockout mice had worse contextual and tone-related learning and memory than did the wild-type mice. The expression of EAAT3, glutamate receptor (GluR)1 and GluR2 in the plasma membrane and of phospho-GluR1 (at Ser 831) and phospho-CaMKII in the hippocampus of the wild-type mice was increased at 30 min after the fear conditioning stimulation. Similar biochemical changes occurred in the amygdala. Fear conditioning also increased the expression of c-Fos and activity-regulated cytoskeleton-associated protein (Arc) in the CA1 regions and of Arc in the entorhinal cortices of the wild-type mice. These biochemical responses were attenuated in the EAAT3 knockout mice. These results suggest that EAAT3 plays a critical role in learning and memory. Our results also provide initial evidence that EAAT3 may have receptor-like functions to participate in the biochemical reactions underlying learning and memory. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. A proposed defect tracking model for classifying the inserted defect reports to enhance software quality control.

    Science.gov (United States)

    Sultan, Torky; Khedr, Ayman E; Sayed, Mostafa

    2013-01-01

    NONE DECLARED Defect tracking systems play an important role in the software development organizations as they can store historical information about defects. There are many research in defect tracking models and systems to enhance their capabilities to be more specifically tracking, and were adopted with new technology. Furthermore, there are different studies in classifying bugs in a step by step method to have clear perception and applicable method in detecting such bugs. This paper shows a new proposed defect tracking model for the purpose of classifying the inserted defects reports in a step by step method for more enhancement of the software quality.

  18. Investigating Thematic Roles through Implicit Learning: Evidence from Light Verb Constructions

    Directory of Open Access Journals (Sweden)

    Eva Wittenberg

    2017-06-01

    Full Text Available The syntactic structure of a sentence is usually a strong predictor of its meaning: Each argument noun phrase (i.e., Subject and Object should map onto exactly one thematic role (i.e., Agent and Patient, respectively. Some constructions, however, are exceptions to this pattern. This paper investigates how the syntactic structure of an utterance contributes to its construal, using ditransitive English light verb constructions, such as “Nils gave a hug to his brother,” as an example of such mismatches: Hugging is a two-role event, but the ditransitive syntactic structure suggests a three-role event. Data from an eye-tracking experiment and behavioral categorization data reveal that listeners learn to categorize sentences according to the number of thematic roles they convey, independent of their syntax. Light verb constructions, however, seem to form a category of their own, in which the syntactic structure leads listeners down an initial incorrect assignment of thematic roles, from which they only partly recover. These results suggest an automatic influence of syntactic argument structure on semantic interpretation and event construal, even in highly frequent constructions.

  19. A problem-based learning curriculum in transition: the emerging role of the library.

    Science.gov (United States)

    Eldredge, J D

    1993-07-01

    This case study describes library education programs that serve the University of New Mexico School of Medicine, known for its innovative problem-based learning (PBL) curricular track. The paper outlines the specific library instruction techniques that are integrated into the curriculum. The adaptation of library instruction to a PBL mode of medical education, including the use of case studies, is discussed in detail. Also addressed are the planning processes for the new PBL curriculum scheduled for implementation in 1993, including the activities of library faculty and staff and the probable new role of the library in the new curriculum.

  20. The Role of Digital Libraries to Support of E-learning

    OpenAIRE

    Akbar Majidi

    2012-01-01

    E-learning is the new pattern of teaching and learning process. The main characteristic of e-learning is delivery of content and learning activity within learning management systems (LMS). E-learning for its success requires that access to resources and information services. Digital libraries can offer different resources and information services on the Internet. Therefore, it will be very useful to support e-learning in this article, after expression of definitions of e-learning and ...

  1. Grower networks support adoption of innovations in pollination management: The roles of social learning, technical learning, and personal experience.

    Science.gov (United States)

    Garbach, Kelly; Morgan, Geoffrey P

    2017-12-15

    , highlighting the potentially critical roles of peer-to-peer networks and social learning in supporting early stages of adoption of innovations. Engaging with grower networks and understanding grower experience with benefits and concerns associated with innovative practices is needed to inform outreach, extension, and policy efforts designed to stimulate management innovations in agroecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. A Learning Perspective On The Role Of Natural Resources In Economic Development

    DEFF Research Database (Denmark)

    Andersen, Allan Dahl

    2011-01-01

    Natural resource-based industries are in economics often is understood as being unable to stimulate growth and development. The latter point has been put forward in the form of the ‘resource curse’ and is epitomised by inter alia Reinert (2007) who sees natural resource-based industries...... as detrimental to growth and development. Still, it will be argued here that Reinert’s approach is unsuitable for grasping the full role of natural resources in economic development because important aspects of industrial dynamics are ignored. In pursuit of the latter research aim two topics in economic research...... will be integrated: (i) the area of learning, innovation, capability building and economic development; (ii) with the area of natural resources and economic development. Such integration will be a contribution to both topics. Hence, this paper seeks to address the question: how can we understand the role of natural...

  3. The Role of Electronic Reserves in Serving and Shaping New Teaching and Learning Environments in UK Universities.

    Science.gov (United States)

    Dugdale, Christine

    1999-01-01

    Describes the ResIDe Electronic Reserve at the University of the West of England (UWE), Bristol, an example of an electronic reserve that has been addressing many access problems and supporting different teaching/learning initiatives. Discusses new roles for the ResIDe electronic library, electronic information management, new librarian roles, and…

  4. How Does the Use of Role-Play Affect the Learning of Year 4 Children in a Predominately EAL Class?

    Science.gov (United States)

    Grant, Katrina; Mistry, Malini Tina

    2010-01-01

    This paper investigates role-play activities and how they can be used within learning for English as an Additional Language (EAL) pupils in a Key Stage 2 setting in England. Through observations, results showed effective role-play activities can be beneficial to EAL pupils, allowing them to practice words and phrases in a relaxed atmosphere…

  5. Role of 3d-ions for radiation defect production in MgO and MgAl2O4

    International Nuclear Information System (INIS)

    Mironova, N.A.; Grinvald, G.A.; Skvortsova, V.N.

    1985-01-01

    Optical properties of MgO and MgAl 2 O 4 crystals containing chromium and manganese impurity ions were studied by exposure to but all types of radiation. Complicated defects of the ''impurity-intrinsic matrix defect'' type were preferably considered. It has been shown that different symmetry center forming chromium ions in MgO:Crsup(3+) change their valency with various efficiency being exposed to external action. Besides, the compensating vacancy does not participate in the hole center formation. For MgOxAl 2 O 3 single crystals the presence of octahedrally coordinated manganese ions suppresses the hole center creation by gamma-irradiation. Studying luminescence spectra of Crsup(3+) ions in MgAl 2 O 4 it has been states that neutron irradiation increases the degree of inversion for the magnesium-aluminium spinel

  6. Point defects in nickel

    International Nuclear Information System (INIS)

    Peretto, P.

    1969-01-01

    The defects in electron irradiated nickel (20 deg. K) or neutron irradiated nickel (28 deg. K) are studied by simultaneous analysis using the magnetic after-effect, electron microscopy and electrical resistivity recovery. We use zone refined nickel (99.999 per cent) which, for some experiments, is alloyed with a small amount of iron (for example 0.1 per cent Fe). The temperature dependant electrical recovery may be divided in four stages. The sub-stages I B (31 deg. K), I C (42 deg. K), I D (from to 57 deg. K) and I E (62 deg. K) of stage I are due to the disappearance of single interstitials into vacancies. The interstitial defect has a split configuration with a migration energy of about 0.15 eV. In the close pair which disappears in stage I B the interstitial is found to be in a 3. neighbour position whilst in stage I D it is near the direction from the vacancy. In stage I E there is no longer any interaction between the interstitial and the vacancy. The stage II is due to more complicated interstitial defects: di-interstitials for stage II B (84 deg. K) and larger and larger interstitial loops for the following sub-stages. The loops may be seen by electron microscopy. Impurities can play the role of nucleation centers for the loops. Stages III A (370 deg. K) and III B (376 deg. K) are due to two types of di-vacancies. During stage IV (410 deg. K) the single vacancies migrate. Vacancy type loops and interstitial type loops grow concurrently and disappear at about 800 deg. K as observed by electron microscopy. (author) [fr

  7. The role of healed N-vacancy defective BC2N sheet and nanotube by NO molecule in oxidation of NO and CO gas molecules

    Science.gov (United States)

    Nematollahi, Parisa; Esrafili, Mehdi D.; Neyts, Erik C.

    2018-06-01

    In this study, the healing of N-vacancy boron carbonitride nanosheet (NV-BC2NNS) and nanotube (NV-BC2NNT) by NO molecule is studied by means of density functional theory calculations. Two different N-vacancies are considered in each of these structures in which the vacancy site is surrounded by either three B-atoms (NB) or by two B- and one C-atom (NBC). By means of the healed BC2NNS and BC2NNT as a support, the removal of two toxic gas molecules (NO and CO) are applicable. It should be noted that the obtained energy barriers of both healing and oxidizing processes are significantly lower than those of graphene, carbon nanotubes or boron nitride nanostructures. Also, at the end of the oxidation process, the pure BC2NNS or BC2NNT is obtained without any additional defects. Therefore, by using this method, we can considerably purify the defective BC2NNS/BC2NNT. Moreover, according to the thermochemistry calculations we can further confirm that the healing process of the NV-BC2NNS and NV-BC2NNT by NO are feasible at room temperature. So, we can claim that this study could be very helpful in both purifying the defective BC2NNS/BC2NNT while in the same effort removing toxic NO and CO gases.

  8. The Prediction of Mental Quality of Life Based on Defectiveness/Shame Schema with Mediating Role of Emotional Intelligence and Coping Strategies by Means of Structural Equations Modeling

    Directory of Open Access Journals (Sweden)

    S. Dehghani

    2014-06-01

    Full Text Available Early maladaptive schema is assumed to be a disrupting factor for quality of life. Yet, the mechanism of this vulnerability is not well known. The purpose of this study was to investigate the characteristic of emotional intelligence and coping strategy with stress as a mediator between early maladaptive defectiveness/ shame and mental quality of life. Participants were 245 men and women in Isfahan who were selected as the sample by availability sampling method. They completed the Petrides and Furnham's Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF, Coping Inventory for stressful situation (CISS and WHO Quality of Life-BREF (WHOQOL-BREF and Young Schema Questionnaire-Short Form (YSQ-SF. Data was analyzed by means of structural equation modeling. The results indicated that the suggested model of study needs modification and only emotional intelligence was the mediator. Standard path coefficient of defectiveness/shame schema to emotional intelligence was -0.55 and emotional intelligence to problem focused coping, emotion focused coping and mental quality of life were 0.49, -0.59 and 0.78 (p<0.05. Based on results, emotional intelligence training can improve mental quality of life and coping strategies in people who have early defectiveness/shame maladaptive schema.

  9. The role of BDNF, leptin, and catecholamines in reward learning in bulimia nervosa.

    Science.gov (United States)

    Homan, Philipp; Grob, Simona; Milos, Gabriella; Schnyder, Ulrich; Eckert, Anne; Lang, Undine; Hasler, Gregor

    2014-12-07

    A relationship between bulimia nervosa and reward-related behavior is supported by several lines of evidence. The dopaminergic dysfunctions in the processing of reward-related stimuli have been shown to be modulated by the neurotrophin brain derived neurotrophic factor (BDNF) and the hormone leptin. Using a randomized, double-blind, placebo-controlled, crossover design, a reward learning task was applied to study the behavior of 20 female subjects with remitted bulimia nervosa and 27 female healthy controls under placebo and catecholamine depletion with alpha-methyl-para-tyrosine (AMPT). The plasma levels of BDNF and leptin were measured twice during the placebo and the AMPT condition, immediately before and 1 hour after a standardized breakfast. AMPT-induced differences in plasma BDNF levels were positively correlated with the AMPT-induced differences in reward learning in the whole sample (P=.05). Across conditions, plasma brain derived neurotrophic factor levels were higher in remitted bulimia nervosa subjects compared with controls (diagnosis effect; P=.001). Plasma BDNF and leptin levels were higher in the morning before compared with after a standardized breakfast across groups and conditions (time effect; Pbulimia nervosa and controls. A role of leptin in reward learning is not supported by this study. However, leptin levels were sensitive to a depletion of catecholamine stores in both remitted bulimia nervosa and controls. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  10. The Role of Context in Third Graders’ Learning of Area Measurement

    Directory of Open Access Journals (Sweden)

    Denny Haris

    2011-01-01

    Full Text Available Many researches showed that the most of students find the difficulty in measuring area. The formula of area tends to be taught directly without involving the conceptual basis and the area measurement are separated from children’s daily experiences. For this reason, the teaching and learning of area measurement was designed and link to a set of students’ experience-based activities. The context of this research is Indonesian traditional handicraft namely anyaman. The study is situated in the context of implementing an Indonesian version of Realistic Mathematics Education, labeled as PMRI in Indonesia. Design Research methodology comprising preliminary design, teaching experiment, and retrospective analysis is applied. This research described the investigation of the context as preliminary of teaching and learning about area measurement held in 3th grade of primary school SDN 119 Palembang. The result of the teaching experiment showed that problem embedded in a context could encourage the students to develop the idea of area measurement concept. The strategies through emergent modeling showed how students’ contribution could be used to develop gradually their reasoning of area measurement concept. In the experience-based activities for learning area measurement, emergent modeling played an important role in the shift of students’ reasoning from informal level towards formal mathematical concepts of area measurement.

  11. On the role of cost-sensitive learning in multi-class brain-computer interfaces.

    Science.gov (United States)

    Devlaminck, Dieter; Waegeman, Willem; Wyns, Bart; Otte, Georges; Santens, Patrick

    2010-06-01

    Brain-computer interfaces (BCIs) present an alternative way of communication for people with severe disabilities. One of the shortcomings in current BCI systems, recently put forward in the fourth BCI competition, is the asynchronous detection of motor imagery versus resting state. We investigated this extension to the three-class case, in which the resting state is considered virtually lying between two motor classes, resulting in a large penalty when one motor task is misclassified into the other motor class. We particularly focus on the behavior of different machine-learning techniques and on the role of multi-class cost-sensitive learning in such a context. To this end, four different kernel methods are empirically compared, namely pairwise multi-class support vector machines (SVMs), two cost-sensitive multi-class SVMs and kernel-based ordinal regression. The experimental results illustrate that ordinal regression performs better than the other three approaches when a cost-sensitive performance measure such as the mean-squared error is considered. By contrast, multi-class cost-sensitive learning enables us to control the number of large errors made between two motor tasks.

  12. Mixed messages in learning communication skills? Students comparing role model behaviour in clerkships with formal training.

    Science.gov (United States)

    Essers, Geurt; Van Weel-Baumgarten, Evelyn; Bolhuis, Sanneke

    2012-01-01

    Medical students learn professional communication through formal training and in clinical practice. Physicians working in clinical practice have a powerful influence on student learning. However, they may demonstrate communication behaviours not aligning with recommendations in training programs. This study aims to identify more precisely what differences students perceive between role model communication behaviour during clerkships and formal training. In a cross-sectional study, data were collected about physicians' communication performance as perceived by students. Students filled out a questionnaire in four different clerkships in their fourth and fifth year. Just over half of the students reported communication similar to formal training. This was especially true for students in the later clerkships (paediatrics and primary care). Good examples were seen in providing information corresponding to patients' needs and in shared decision making, although students often noted that in fact the doctor made the decision. Bad examples were observed in exploring cognitions and emotions, and in providing information meeting patient's pace. Further study is needed on actual physician behaviour in clinical practice. From our results, we conclude that students need help in reflecting on and learning from the gap in communication patterns they observe in training versus clinical practice.

  13. Decisional Procrastination in Academic Settings: The Role of Metacognitions and Learning Strategies

    Directory of Open Access Journals (Sweden)

    Valeria de Palo

    2017-06-01

    Full Text Available Nowadays, university students suffer from a broad range of problems, such as educational underachievement or the inability to control themselves, that lead to procrastination as a consequence. The present research aimed at analyzing the determinants of decisional procrastination among undergraduate students and at assessing a path model in which self regulated learning strategies mediated the relationship between metacognitive beliefs about procrastination and decisional procrastination. 273 students from Southern Italy filled out a questionnaire composed by: the socio-demographic section, the Metacognitive Beliefs About Procrastination Questionnaire, the procrastination subscale of the Melbourne Decision Making Questionnaire, and the Anxiety, the Time Management, and the Information Processing subscales of the Learning and Study Strategies Inventory. Results showed that the relationship between negative and positive metacognitive beliefs about procrastination and decisional procrastination was mediated only by time management and anxiety. Such findings underlined the crucial role played by learning strategies in predicting the tendency to delay decisional situations and in mediating the relationship between metacognitive beliefs about procrastination and decisional procrastination.

  14. Decisional Procrastination in Academic Settings: The Role of Metacognitions and Learning Strategies.

    Science.gov (United States)

    de Palo, Valeria; Monacis, Lucia; Miceli, Silvana; Sinatra, Maria; Di Nuovo, Santo

    2017-01-01

    Nowadays, university students suffer from a broad range of problems, such as educational underachievement or the inability to control themselves, that lead to procrastination as a consequence. The present research aimed at analyzing the determinants of decisional procrastination among undergraduate students and at assessing a path model in which self regulated learning strategies mediated the relationship between metacognitive beliefs about procrastination and decisional procrastination. 273 students from Southern Italy filled out a questionnaire composed by: the socio-demographic section, the Metacognitive Beliefs About Procrastination Questionnaire, the procrastination subscale of the Melbourne Decision Making Questionnaire, and the Anxiety, the Time Management, and the Information Processing subscales of the Learning and Study Strategies Inventory. Results showed that the relationship between negative and positive metacognitive beliefs about procrastination and decisional procrastination was mediated only by time management and anxiety. Such findings underlined the crucial role played by learning strategies in predicting the tendency to delay decisional situations and in mediating the relationship between metacognitive beliefs about procrastination and decisional procrastination.

  15. Different role of the ventral medial prefrontal cortex on modulation of innate and associative learned fear.

    Science.gov (United States)

    Lisboa, S F; Stecchini, M F; Corrêa, F M A; Guimarães, F S; Resstel, L B M

    2010-12-15

    Reversible inactivation of the ventral portion of medial prefrontal cortex (vMPFC) of the rat brain has been shown to induce anxiolytic-like effects in animal models based on associative learning. The role of this brain region in situations involving innate fear, however, is still poorly understood, with several contradictory results in the literature. The objective of the present work was to verify in male Wistar rats the effects of vMPFC administration of cobalt chloride (CoCl(2)), a selective inhibitor of synaptic activity, in rats submitted to two models based on innate fear, the elevated plus-maze (EPM) and light-dark box (LDB), comparing the results with those obtained in two models involving associative learning, the contextual fear conditioning (CFC) and Vogel conflict (VCT) tests. The results showed that, whereas CoCl(2) induced anxiolytic-like effects in the CFC and VCT tests, it enhanced anxiety in rats submitted to the EPM and LDB. Together these results indicate that the vMPFC plays an important but complex role in the modulation of defensive-related behaviors, which seems to depend on the nature of the anxiety/fear inducing stimuli. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  16. Functional neuroanatomy of amygdalohippocampal interconnections and their role in learning and memory.

    Science.gov (United States)

    McDonald, Alexander J; Mott, David D

    2017-03-01

    The amygdalar nuclear complex and hippocampal/parahippocampal region are key components of the limbic system that play a critical role in emotional learning and memory. This Review discusses what is currently known about the neuroanatomy and neurotransmitters involved in amygdalo-hippocampal interconnections, their functional roles in learning and memory, and their involvement in mnemonic dysfunctions associated with neuropsychiatric and neurological diseases. Tract tracing studies have shown that the interconnections between discrete amygdalar nuclei and distinct layers of individual hippocampal/parahippocampal regions are robust and complex. Although it is well established that glutamatergic pyramidal cells in the amygdala and hippocampal region are the major players mediating interconnections between these regions, recent studies suggest that long-range GABAergic projection neurons are also involved. Whereas neuroanatomical studies indicate that the amygdala only has direct interconnections with the ventral hippocampal region, electrophysiological studies and behavioral studies investigating fear conditioning and extinction, as well as amygdalar modulation of hippocampal-dependent mnemonic functions, suggest that the amygdala interacts with dorsal hippocampal regions via relays in the parahippocampal cortices. Possible pathways for these indirect interconnections, based on evidence from previous tract tracing studies, are discussed in this Review. Finally, memory disorders associated with dysfunction or damage to the amygdala, hippocampal region, and/or their interconnections are discussed in relation to Alzheimer's disease, posttraumatic stress disorder (PTSD), and temporal lobe epilepsy. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Rhythm Perception and Its Role in Perception and Learning of Dysrhythmic Speech.

    Science.gov (United States)

    Borrie, Stephanie A; Lansford, Kaitlin L; Barrett, Tyson S

    2017-03-01

    The perception of rhythm cues plays an important role in recognizing spoken language, especially in adverse listening conditions. Indeed, this has been shown to hold true even when the rhythm cues themselves are dysrhythmic. This study investigates whether expertise in rhythm perception provides a processing advantage for perception (initial intelligibility) and learning (intelligibility improvement) of naturally dysrhythmic speech, dysarthria. Fifty young adults with typical hearing participated in 3 key tests, including a rhythm perception test, a receptive vocabulary test, and a speech perception and learning test, with standard pretest, familiarization, and posttest phases. Initial intelligibility scores were calculated as the proportion of correct pretest words, while intelligibility improvement scores were calculated by subtracting this proportion from the proportion of correct posttest words. Rhythm perception scores predicted intelligibility improvement scores but not initial intelligibility. On the other hand, receptive vocabulary scores predicted initial intelligibility scores but not intelligibility improvement. Expertise in rhythm perception appears to provide an advantage for processing dysrhythmic speech, but a familiarization experience is required for the advantage to be realized. Findings are discussed in relation to the role of rhythm in speech processing and shed light on processing models that consider the consequence of rhythm abnormalities in dysarthria.

  18. Dipole defects in beryl

    International Nuclear Information System (INIS)

    Holanda, B A; Cordeiro, R C; Blak, A R

    2010-01-01

    Dipole defects in gamma irradiated and thermally treated beryl (Be 3 Al 2 Si 6 O 18 ) samples have been studied using the Thermally Stimulated Depolarization Currents (TSDC) technique. TSDC experiments were performed in pink (morganite), green (emerald), blue (aquamarine) and colourless (goshenite) natural beryl. TSDC spectra present dipole peaks at 190K, 220K, 280K and 310K that change after gamma irradiation and thermal treatments. In morganite samples, for thermal treatments between 700K and 1100K, the 280K peak increase in intensity and the band at 220K disappears. An increase of the 280K peak and a decrease of the 190K peak were observed in the TSDC spectra of morganite after a gamma irradiation of 25kGy performed after the thermal treatments. In the case of emerald samples, thermal treatments enhanced the 280K peak and gamma irradiation partially destroyed this band. The goshenite TSDC spectra present only one band at 280K that is not affected either by thermal treatments or by gamma irradiation. All the observed peaks are of dipolar origin because the intensity of the bands is linearly dependent on the polarization field, behaviour of dipole defects. The systematic study, by means of TSDC measurements, of ionizing irradiation effects and thermal treatments in these crystals makes possible a better understanding of the role played by the impurities in beryl crystals.

  19. Roles of NO signaling in long-term memory formation in visual learning in an insect.

    Directory of Open Access Journals (Sweden)

    Yukihisa Matsumoto

    Full Text Available Many insects exhibit excellent capability of visual learning, but the molecular and neural mechanisms are poorly understood. This is in contrast to accumulation of information on molecular and neural mechanisms of olfactory learning in insects. In olfactory learning in insects, it has been shown that cyclic AMP (cAMP signaling critically participates in the formation of protein synthesis-dependent long-term memory (LTM and, in some insects, nitric oxide (NO-cyclic GMP (cGMP signaling also plays roles in LTM formation. In this study, we examined the possible contribution of NO-cGMP signaling and cAMP signaling to LTM formation in visual pattern learning in crickets. Crickets that had been subjected to 8-trial conditioning to associate a visual pattern with water reward exhibited memory retention 1 day after conditioning, whereas those subjected to 4-trial conditioning exhibited 30-min memory retention but not 1-day retention. Injection of cycloheximide, a protein synthesis inhibitor, into the hemolymph prior to 8-trial conditioning blocked formation of 1-day memory, whereas it had no effect on 30-min memory formation, indicating that 1-day memory can be characterized as protein synthesis-dependent long-term memory (LTM. Injection of an inhibitor of the enzyme producing an NO or cAMP prior to 8-trial visual conditioning blocked LTM formation, whereas it had no effect on 30-min memory formation. Moreover, injection of an NO donor, cGMP analogue or cAMP analogue prior to 4-trial conditioning induced LTM. Induction of LTM by an NO donor was blocked by DDA, an inhibitor of adenylyl cyclase, an enzyme producing cAMP, but LTM induction by a cAMP analogue was not impaired by L-NAME, an inhibitor of NO synthase. The results indicate that cAMP signaling is downstream of NO signaling for visual LTM formation. We conclude that visual learning and olfactory learning share common biochemical cascades for LTM formation.

  20. The role of food experiences during early childhood in food pleasure learning.

    Science.gov (United States)

    Nicklaus, Sophie

    2016-09-01

    Infants are born equipped to ingest nutrients, but have to learn what to eat. This must occur early, because the mode of feeding evolves dramatically, from "tube" feeding in utero to eating family foods. Eating habits established during early years contribute to the development of subsequent eating habits. Therefore, it is fundamental to understand the most important early periods (between birth and 2 years, i.e. onset of food neophobia) for the development of eating habits and the drivers of this development. The role of pleasure in eating is central, especially during childhood when cognitive drivers of food choices may be less prominent than later in life. It is not easy to define and measure pleasure of eating in early childhood. However, it is possible to identify the characteristics of the eating experience which contribute to drive infant's eating and to shape preferences (food sensory properties; food rewarding properties; social context of eating). The learning processes involve repeated exposure (including to a variety of flavours), association with post-absorptive consequences and with contextual signals (including family members). The important early periods for learning food pleasure start being well identified. Beyond the first flavour discoveries during the prenatal and lactation periods (through the infant's exposure to flavours from foods of the mother's diet), the most important phase may be the beginning of complementary feeding. Infants discover the sensory (texture, taste and flavour) and nutritional properties (energy density) of the foods that will ultimately compose their adult diet; parents are still in charge of providing appropriate foods, timing, context for eating. Inter-individual differences in food pleasure learning, related to temperamental dimensions, or to sensory sensitivity also have to be taken into account. Copyright © 2015 Elsevier Ltd. All rights reserved.