WorldWideScience

Sample records for providing external memory

  1. Parallel External Memory Graph Algorithms

    DEFF Research Database (Denmark)

    Arge, Lars Allan; Goodrich, Michael T.; Sitchinava, Nodari

    2010-01-01

    In this paper, we study parallel I/O efficient graph algorithms in the Parallel External Memory (PEM) model, one o f the private-cache chip multiprocessor (CMP) models. We study the fundamental problem of list ranking which leads to efficient solutions to problems on trees, such as computing lowest...... an optimal speedup of ¿(P) in parallel I/O complexity and parallel computation time, compared to the single-processor external memory counterparts....

  2. Computing betweenness centrality in external memory

    DEFF Research Database (Denmark)

    Arge, Lars; Goodrich, Michael T.; Walderveen, Freek van

    2013-01-01

    Betweenness centrality is one of the most well-known measures of the importance of nodes in a social-network graph. In this paper we describe the first known external-memory and cache-oblivious algorithms for computing betweenness centrality. We present four different external-memory algorithms...

  3. RAM-efficient external memory sorting

    DEFF Research Database (Denmark)

    Arge, Lars; Thorup, Mikkel

    2013-01-01

    In recent years a large number of problems have been considered in external memory models of computation, where the complexity measure is the number of blocks of data that are moved between slow external memory and fast internal memory (also called I/Os). In practice, however, internal memory time...... often dominates the total running time once I/O-efficiency has been obtained. In this paper we study algorithms for fundamental problems that are simultaneously I/O-efficient and internal memory efficient in the RAM model of computation....

  4. Fault Tolerant External Memory Algorithms

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Brodal, Gerth Stølting; Mølhave, Thomas

    2009-01-01

    Algorithms dealing with massive data sets are usually designed for I/O-efficiency, often captured by the I/O model by Aggarwal and Vitter. Another aspect of dealing with massive data is how to deal with memory faults, e.g. captured by the adversary based faulty memory RAM by Finocchi and Italiano....... However, current fault tolerant algorithms do not scale beyond the internal memory. In this paper we investigate for the first time the connection between I/O-efficiency in the I/O model and fault tolerance in the faulty memory RAM, and we assume that both memory and disk are unreliable. We show a lower...... bound on the number of I/Os required for any deterministic dictionary that is resilient to memory faults. We design a static and a dynamic deterministic dictionary with optimal query performance as well as an optimal sorting algorithm and an optimal priority queue. Finally, we consider scenarios where...

  5. External-Memory Algorithms and Data Structures

    DEFF Research Database (Denmark)

    Arge, Lars; Zeh, Norbert

    2010-01-01

    The data sets involved in many modern applications are often too massive to fit in main memory of even the most powerful computers and must therefore reside on disk. Thus communication between internal and external memory, and not actual computation time, becomes the bottleneck in the computation....... This is due to the huge difference in access time of fast internal memory and slower external memory such as disks. The goal of theoretical work in the area of external memory algorithms (also called I/O algorithms or out-of-core algorithms) has been to develop algorithms that minimize the Input...... in parallel and the use of parallel disks has received a lot of theoretical attention. See below for recent surveys of theoretical results in the area of I/O-efficient algorithms. TPIE is designed to bridge the gap between the theory and practice of parallel I/O systems. It is intended to demonstrate all...

  6. External Memory Pipelining Made Easy With TPIE

    OpenAIRE

    Arge, Lars; Rav, Mathias; Svendsen, Svend C.; Truelsen, Jakob

    2017-01-01

    When handling large datasets that exceed the capacity of the main memory, movement of data between main memory and external memory (disk), rather than actual (CPU) computation time, is often the bottleneck in the computation. Since data is moved between disk and main memory in large contiguous blocks, this has led to the development of a large number of I/O-efficient algorithms that minimize the number of such block movements. TPIE is one of two major libraries that have been developed to sup...

  7. Lower Bounds for External Memory Dictionaries

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Fagerberg, Rolf

    2003-01-01

    We study trade-offs between the update time and the query time for comparison based external memory dictionaries. The main contributions of this paper are two lower bound trade offs between the I/O complexity of member queries and insertions: If N < M insertions perform at most δ · N/B I/Os, then......We study trade-offs between the update time and the query time for comparison based external memory dictionaries. The main contributions of this paper are two lower bound trade offs between the I/O complexity of member queries and insertions: If N

  8. On (dynamic) range minimum queries in external memory

    DEFF Research Database (Denmark)

    Arge, L.; Fischer, Johannes; Sanders, Peter

    2013-01-01

    We study the one-dimensional range minimum query (RMQ) problem in the external memory model. We provide the first space-optimal solution to the batched static version of the problem. On an instance with N elements and Q queries, our solution takes Θ(sort(N + Q)) = Θ( N+QB log M /B N+QB ) I...

  9. Optimal External-Memory Planar Point Enclosure

    DEFF Research Database (Denmark)

    Arge, Lars; Samoladas, Vasilis; Yi, Ke

    2007-01-01

    .g. spatial and temporal databases, and is dual to the important and well-studied orthogonal range searching problem. Surprisingly, despite the fact that the problem can be solved optimally in internal memory with linear space and O(log N+K) query time, we show that one cannot construct a linear sized......In this paper we study the external memory planar point enclosure problem: Given N axis-parallel rectangles in the plane, construct a data structure on disk (an index) such that all K rectangles containing a query point can be reported I/O-efficiently. This problem has important applications in e...... external memory point enclosure data structure that can be used to answer a query in O(log  B N+K/B) I/Os, where B is the disk block size. To obtain this bound, Ω(N/B 1−ε ) disk blocks are needed for some constant ε>0. With linear space, the best obtainable query bound is O(log 2 N+K/B) if a linear output...

  10. Multithreaded Asynchronous Graph Traversal for In-Memory and Semi-External Memory

    KAUST Repository

    Pearce, Roger

    2010-11-01

    Processing large graphs is becoming increasingly important for many domains such as social networks, bioinformatics, etc. Unfortunately, many algorithms and implementations do not scale with increasing graph sizes. As a result, researchers have attempted to meet the growing data demands using parallel and external memory techniques. We present a novel asynchronous approach to compute Breadth-First-Search (BFS), Single-Source-Shortest-Paths, and Connected Components for large graphs in shared memory. Our highly parallel asynchronous approach hides data latency due to both poor locality and delays in the underlying graph data storage. We present an experimental study applying our technique to both In-Memory and Semi-External Memory graphs utilizing multi-core processors and solid-state memory devices. Our experiments using synthetic and real-world datasets show that our asynchronous approach is able to overcome data latencies and provide significant speedup over alternative approaches. For example, on billion vertex graphs our asynchronous BFS scales up to 14x on 16-cores. © 2010 IEEE.

  11. External Memory Planar Point Location with Logarithmic Updates

    DEFF Research Database (Denmark)

    Arge, Lars; Brodal, Gerth Stølting; Satti, Srinivasa Rao

    2008-01-01

    Point location is an extremely well-studied problem both in internal memory models and recently also in the external memory model. In this paper, we present an I/O-efficient dynamic data structure for point location in general planar subdivisions. Our structure uses linear space to store...

  12. Analogical Reasoning in Adolescents with Intellectual Disability: Effects of External Memories and Time Processing

    Science.gov (United States)

    Denaes, Caroline; Berger, Jean-Louis

    2014-01-01

    Analogical reasoning involves the comparison of pictures as well as the memorisation of relations. Young children (4-7 years old) and students with moderate intellectual disability have a short memory span, which hampers them in succeeding traditional analogical tests. In the present study, we investigated if, by providing external memory hints,…

  13. Efficient external memory structures for range-aggregate queries

    DEFF Research Database (Denmark)

    Agarwal, P.K.; Yang, J.; Arge, L.

    2013-01-01

    We present external memory data structures for efficiently answering range-aggregate queries. The range-aggregate problem is defined as follows: Given a set of weighted points in Rd, compute the aggregate of the weights of the points that lie inside a d-dimensional orthogonal query rectangle. The...

  14. Dynamic State Space Partitioning for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami; Kristensen, Lars Michael

    2009-01-01

    We describe a dynamic partitioning scheme usable by model checking techniques that divide the state space into partitions, such as most external memory and distributed model checking algorithms. The goal of the scheme is to reduce the number of transitions that link states belonging to different...

  15. Hybrid computing using a neural network with dynamic external memory.

    Science.gov (United States)

    Graves, Alex; Wayne, Greg; Reynolds, Malcolm; Harley, Tim; Danihelka, Ivo; Grabska-Barwińska, Agnieszka; Colmenarejo, Sergio Gómez; Grefenstette, Edward; Ramalho, Tiago; Agapiou, John; Badia, Adrià Puigdomènech; Hermann, Karl Moritz; Zwols, Yori; Ostrovski, Georg; Cain, Adam; King, Helen; Summerfield, Christopher; Blunsom, Phil; Kavukcuoglu, Koray; Hassabis, Demis

    2016-10-27

    Artificial neural networks are remarkably adept at sensory processing, sequence learning and reinforcement learning, but are limited in their ability to represent variables and data structures and to store data over long timescales, owing to the lack of an external memory. Here we introduce a machine learning model called a differentiable neural computer (DNC), which consists of a neural network that can read from and write to an external memory matrix, analogous to the random-access memory in a conventional computer. Like a conventional computer, it can use its memory to represent and manipulate complex data structures, but, like a neural network, it can learn to do so from data. When trained with supervised learning, we demonstrate that a DNC can successfully answer synthetic questions designed to emulate reasoning and inference problems in natural language. We show that it can learn tasks such as finding the shortest path between specified points and inferring the missing links in randomly generated graphs, and then generalize these tasks to specific graphs such as transport networks and family trees. When trained with reinforcement learning, a DNC can complete a moving blocks puzzle in which changing goals are specified by sequences of symbols. Taken together, our results demonstrate that DNCs have the capacity to solve complex, structured tasks that are inaccessible to neural networks without external read-write memory.

  16. Multithreaded Asynchronous Graph Traversal for In-Memory and Semi-External Memory

    KAUST Repository

    Pearce, Roger; Gokhale, Maya; Amato, Nancy M.

    2010-01-01

    . Our highly parallel asynchronous approach hides data latency due to both poor locality and delays in the underlying graph data storage. We present an experimental study applying our technique to both In-Memory and Semi-External Memory graphs utilizing

  17. Lower Bounds in the Asymmetric External Memory Model

    DEFF Research Database (Denmark)

    Jacob, Riko; Sitchinava, Nodari

    2017-01-01

    Motivated by the asymmetric read and write costs of emerging non-volatile memory technologies, we study lower bounds for the problems of sorting, permuting and multiplying a sparse matrix by a dense vector in the asymmetric external memory model (AEM). Given an AEM with internal (symmetric) memory...... of size M, transfers between symmetric and asymmetric memory in blocks of size B and the ratio ω between write and read costs, we show Ω(min (N, ωN/B logω M/B N/B) lower bound for the cost of permuting N input elements. This lower bound also applies to the problem of sorting N elements. This proves...

  18. DecreaseKeys are Expensive for External Memory Priority Queues

    OpenAIRE

    Eenberg, Kasper; Larsen, Kasper Green; Yu, Huacheng

    2016-01-01

    One of the biggest open problems in external memory data structures is the priority queue problem with DecreaseKey operations. If only Insert and ExtractMin operations need to be supported, one can design a comparison-based priority queue performing $O((N/B)\\lg_{M/B} N)$ I/Os over a sequence of $N$ operations, where $B$ is the disk block size in number of words and $M$ is the main memory size in number of words. This matches the lower bound for comparison-based sorting and is hence optimal fo...

  19. emMAW: computing minimal absent words in external memory.

    Science.gov (United States)

    Héliou, Alice; Pissis, Solon P; Puglisi, Simon J

    2017-09-01

    The biological significance of minimal absent words has been investigated in genomes of organisms from all domains of life. For instance, three minimal absent words of the human genome were found in Ebola virus genomes. There exists an O(n) -time and O(n) -space algorithm for computing all minimal absent words of a sequence of length n on a fixed-sized alphabet based on suffix arrays. A standard implementation of this algorithm, when applied to a large sequence of length n , requires more than 20 n  bytes of RAM. Such memory requirements are a significant hurdle to the computation of minimal absent words in large datasets. We present emMAW, the first external-memory algorithm for computing minimal absent words. A free open-source implementation of our algorithm is made available. This allows for computation of minimal absent words on far bigger data sets than was previously possible. Our implementation requires less than 3 h on a standard workstation to process the full human genome when as little as 1 GB of RAM is made available. We stress that our implementation, despite making use of external memory, is fast; indeed, even on relatively smaller datasets when enough RAM is available to hold all necessary data structures, it is less than two times slower than state-of-the-art internal-memory implementations. https://github.com/solonas13/maw (free software under the terms of the GNU GPL). alice.heliou@lix.polytechnique.fr or solon.pissis@kcl.ac.uk. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  20. Configurable memory system and method for providing atomic counting operations in a memory device

    Science.gov (United States)

    Bellofatto, Ralph E.; Gara, Alan G.; Giampapa, Mark E.; Ohmacht, Martin

    2010-09-14

    A memory system and method for providing atomic memory-based counter operations to operating systems and applications that make most efficient use of counter-backing memory and virtual and physical address space, while simplifying operating system memory management, and enabling the counter-backing memory to be used for purposes other than counter-backing storage when desired. The encoding and address decoding enabled by the invention provides all this functionality through a combination of software and hardware.

  1. An exploration of the relations between external representations and working memory.

    Directory of Open Access Journals (Sweden)

    Jiajie Zhang

    Full Text Available It is commonly hypothesized that external representations serve as memory aids and improve task performance by means of expanding the limited capacity of working memory. However, very few studies have directly examined this memory aid hypothesis. By systematically manipulating how information is available externally versus internally in a sequential number comparison task, three experiments were designed to investigate the relation between external representations and working memory. The experimental results show that when the task requires information from both external representations and working memory, it is the interaction of information from the two sources that determines task performance. In particular, when information from the two sources does not match well, external representations hinder instead of enhance task performance. The study highlights the important role the coordination among different representations plays in distributed cognition. The general relations between external representations and working memory are discussed.

  2. Worst-case efficient external-memory priority queues

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Katajainen, Jyrki

    1998-01-01

    A priority queue Q is a data structure that maintains a collection of elements, each element having an associated priority drawn from a totally ordered universe, under the operations Insert, which inserts an element into Q, and DeleteMin, which deletes an element with the minimum priority from Q....... In this paper a priority-queue implementation is given which is efficient with respect to the number of block transfers or I/Os performed between the internal and external memories of a computer. Let B and M denote the respective capacity of a block and the internal memory measured in elements. The developed...... data structure handles any intermixed sequence of Insert and DeleteMin operations such that in every disjoint interval of B consecutive priorityqueue operations at most clogM/B N/M I/Os are performed, for some positive constant c. These I/Os are divided evenly among the operations: if B ≥ clogM/B N...

  3. Hänsel, Gretel and the slime mould—how an external spatial memory aids navigation in complex environments

    Science.gov (United States)

    Smith-Ferguson, Jules; Reid, Chris R.; Latty, Tanya; Beekman, Madeleine

    2017-10-01

    The ability to navigate through an environment is critical to most organisms’ ability to survive and reproduce. The presence of a memory system greatly enhances navigational success. Therefore, natural selection is likely to drive the creation of memory systems, even in non-neuronal organisms, if having such a system is adaptive. Here we examine if the external spatial memory system present in the acellular slime mould, Physarum polycephalum, provides an adaptive advantage for resource acquisition. P. polycephalum lays tracks of extracellular slime as it moves through its environment. Previous work has shown that the presence of extracellular slime allows the organism to escape from a trap in laboratory experiments simply by avoiding areas previously explored. Here we further investigate the benefits of using extracellular slime as an external spatial memory by testing the organism’s ability to navigate through environments of differing complexity with and without the ability to use its external memory. Our results suggest that the external memory has an adaptive advantage in ‘open’ and simple bounded environments. However, in a complex bounded environment, the extracellular slime provides no advantage, and may even negatively affect the organism’s navigational abilities. Our results indicate that the exact experimental set up matters if one wants to fully understand how the presence of extracellular slime affects the slime mould’s search behaviour.

  4. Hänsel, Gretel and the slime mould—how an external spatial memory aids navigation in complex environments

    International Nuclear Information System (INIS)

    Smith-Ferguson, Jules; Latty, Tanya; Beekman, Madeleine; Reid, Chris R

    2017-01-01

    The ability to navigate through an environment is critical to most organisms’ ability to survive and reproduce. The presence of a memory system greatly enhances navigational success. Therefore, natural selection is likely to drive the creation of memory systems, even in non-neuronal organisms, if having such a system is adaptive. Here we examine if the external spatial memory system present in the acellular slime mould, Physarum polycephalum , provides an adaptive advantage for resource acquisition. P. polycephalum lays tracks of extracellular slime as it moves through its environment. Previous work has shown that the presence of extracellular slime allows the organism to escape from a trap in laboratory experiments simply by avoiding areas previously explored. Here we further investigate the benefits of using extracellular slime as an external spatial memory by testing the organism’s ability to navigate through environments of differing complexity with and without the ability to use its external memory. Our results suggest that the external memory has an adaptive advantage in ‘open’ and simple bounded environments. However, in a complex bounded environment, the extracellular slime provides no advantage, and may even negatively affect the organism’s navigational abilities. Our results indicate that the exact experimental set up matters if one wants to fully understand how the presence of extracellular slime affects the slime mould’s search behaviour. (paper)

  5. External details revisited - A new taxonomy for coding 'non-episodic' content during autobiographical memory retrieval.

    Science.gov (United States)

    Strikwerda-Brown, Cherie; Mothakunnel, Annu; Hodges, John R; Piguet, Olivier; Irish, Muireann

    2018-04-24

    Autobiographical memory (ABM) is typically held to comprise episodic and semantic elements, with the vast majority of studies to date focusing on profiles of episodic details in health and disease. In this context, 'non-episodic' elements are often considered to reflect semantic processing or are discounted from analyses entirely. Mounting evidence suggests that rather than reflecting one unitary entity, semantic autobiographical information may contain discrete subcomponents, which vary in their relative degree of semantic or episodic content. This study aimed to (1) review the existing literature to formally characterize the variability in analysis of 'non-episodic' content (i.e., external details) on the Autobiographical Interview and (2) use these findings to create a theoretically grounded framework for coding external details. Our review exposed discrepancies in the reporting and interpretation of external details across studies, reinforcing the need for a new, consistent approach. We validated our new external details scoring protocol (the 'NExt' taxonomy) in patients with Alzheimer's disease (n = 18) and semantic dementia (n = 13), and 20 healthy older Control participants and compared profiles of the NExt subcategories across groups and time periods. Our results revealed increased sensitivity of the NExt taxonomy in discriminating between ABM profiles of patient groups, when compared to traditionally used internal and external detail metrics. Further, remote and recent autobiographical memories displayed distinct compositions of the NExt detail types. This study is the first to provide a fine-grained and comprehensive taxonomy to parse external details into intuitive subcategories and to validate this protocol in neurodegenerative disorders. © 2018 The British Psychological Society.

  6. Effects of internal and external vividness on hippocampal connectivity during memory retrieval.

    Science.gov (United States)

    Ford, Jaclyn H; Kensinger, Elizabeth A

    2016-10-01

    Successful memory for an image can be supported by retrieval of one's personal reaction to the image (i.e., internal vividness), as well as retrieval of the specific details of the image itself (i.e., external vividness). Prior research suggests that memory vividness relies on regions within the medial temporal lobe, particularly the hippocampus, but it is unclear whether internal and external vividness are supported by the hippocampus in a similar way. To address this open question, the current study examined hippocampal connectivity associated with enhanced internal and external vividness ratings during retrieval. Participants encoded complex visual images paired with verbal titles. During a scanned retrieval session, they were presented with the titles and asked whether each had been seen with an image during encoding. Following retrieval of each image, participants were asked to rate internal and external vividness. Increased hippocampal activity was associated with higher vividness ratings for both scales, supporting prior evidence implicating the hippocampus in retrieval of memory detail. However, different patterns of hippocampal connectivity related to enhanced external and internal vividness. Further, hippocampal connectivity with medial prefrontal regions was associated with increased ratings of internal vividness, but with decreased ratings of external vividness. These findings suggest that the hippocampus may contribute to increased internal and external vividness via distinct mechanisms and that external and internal vividness of memories should be considered as separable measures. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Providing for organizational memory in computer supported meetings

    OpenAIRE

    Schwabe, Gerhard

    1994-01-01

    Meeting memory features are poorly integrated into current group support systems (GSS). In this article, I discuss how to introduce meeting memory functionality into a GSS. The article first introduces the benefits of effective meetings and organizational memory to an organization. Then, the following challenges to design are discussed: How to store semantically rich output, how to build up the meeting memory with a minimum of additional effort, how to integrate meeting memory into organizati...

  8. Resource-sharing between internal maintenance and external selection modulates attentional capture by working memory content

    Directory of Open Access Journals (Sweden)

    Anastasia eKiyonaga

    2014-08-01

    Full Text Available It is unclear why and under what circumstances working memory (WM and attention interact. Here, we apply the logic of the time-based resource-sharing (TBRS model of WM (e.g., Barrouillet, Bernardin, & Camos, 2004 to explore the mixed findings of a separate, but related, literature that studies the guidance of visual attention by WM contents. Specifically, we hypothesize that the linkage between WM representations and visual attention is governed by a time-shared cognitive resource that alternately refreshes internal (WM and selects external (visual attention information. If this were the case, WM content should guide visual attention (involuntarily, but only when there is time for it to be refreshed in an internal focus of attention. To provide an initial test for this hypothesis, we examined whether the amount of unoccupied time during a WM delay could impact the magnitude of attentional capture by WM contents. Participants were presented with a series of visual search trials while they maintained a WM cue for a delayed-recognition test. WM cues could coincide with the search target, a distracter, or neither. We varied both the number of searches to be performed, and the amount of available time to perform them. Slowing of visual search by a WM matching distracter—and facilitation by a matching target—were curtailed when the delay was filled with fast-paced (refreshing-preventing search trials, as was subsequent memory probe accuracy. WM content may, therefore, only capture visual attention when it can be refreshed, suggesting that internal (WM and external attention demands reciprocally impact one another because they share a limited resource. The TBRS rationale can thus be applied in a novel context to explain why WM contents capture attention, and under what conditions that effect should be observed.

  9. Need for Cognition and False Memory: Can One's Natural Processing Style Be Manipulated by External Factors?

    Science.gov (United States)

    Wootan, Samantha S; Leding, Juliana K

    2015-01-01

    The purpose of this experiment was to provide an enhanced understanding of need for cognition (NFC) and its influence on one's memory accuracy. People who are high in NFC tend to put more cognitive effort into their mental processes than their low-NFC counterparts. To determine whether one's natural processing tendencies, as determined by NFC, can be influenced by external factors, manipulations to levels of processing were added. Participants viewed word lists from the Deese-Roediger-McDermott (DRM) paradigm and were instructed to process half of the DRM lists deeply and the other half shallowly. After all the lists were presented, participants completed 3 successive recall tests. The deep processing condition produced higher rates of false memories for both NFC groups than the shallow processing condition. In addition, the high-NFC group produced higher rates of target recall in both the deep and shallow conditions than the low-NFC group. However, the high-NFC group also produced higher rates of false recall for the shallowly processed lists. These data indicate that high-NFC people exhibit enhanced target recall for word lists, which may come at the expense of overall accuracy due to the increase of false recall.

  10. External Memory Algorithms for Diameter and All-Pair Shortest-Paths on Sparse Graphs

    DEFF Research Database (Denmark)

    Arge, Lars; Meyer, Ulrich; Toma, Laura

    2004-01-01

    We present several new external-memory algorithms for finding all-pairs shortest paths in a V -node, Eedge undirected graph. For all-pairs shortest paths and diameter in unweighted undirected graphs we present cache-oblivious algorithms with O(V · E B logM B E B) I/Os, where B is the block-size a...

  11. Recovering Faces from Memory: The Distracting Influence of External Facial Features

    Science.gov (United States)

    Frowd, Charlie D.; Skelton, Faye; Atherton, Chris; Pitchford, Melanie; Hepton, Gemma; Holden, Laura; McIntyre, Alex H.; Hancock, Peter J. B.

    2012-01-01

    Recognition memory for unfamiliar faces is facilitated when contextual cues (e.g., head pose, background environment, hair and clothing) are consistent between study and test. By contrast, inconsistencies in external features, especially hair, promote errors in unfamiliar face-matching tasks. For the construction of facial composites, as carried…

  12. Continual and One-Shot Learning Through Neural Networks with Dynamic External Memory

    DEFF Research Database (Denmark)

    Lüders, Benno; Schläger, Mikkel; Korach, Aleksandra

    2017-01-01

    it easier to find unused memory location and therefor facilitates the evolution of continual learning networks. Our results suggest that augmenting evolving networks with an external memory component is not only a viable mechanism for adaptive behaviors in neuroevolution but also allows these networks...... a new task is learned. This paper takes a step in overcoming this limitation by building on the recently proposed Evolving Neural Turing Machine (ENTM) approach. In the ENTM, neural networks are augmented with an external memory component that they can write to and read from, which allows them to store...... associations quickly and over long periods of time. The results in this paper demonstrate that the ENTM is able to perform one-shot learning in reinforcement learning tasks without catastrophic forgetting of previously stored associations. Additionally, we introduce a new ENTM default jump mechanism that makes...

  13. Outsourcing Physical Education in Primary Schools: Evaluating the Impact of Externally Provided Programmes on Generalist Teachers

    Science.gov (United States)

    Whipp, Peter R.; Hutton, Heidi; Grove, J. Robert; Jackson, Ben

    2011-01-01

    In place of generalist delivery, externally provided physical activity programmes (EPPAPs) are potentially an effective method for offering primary school students specialist physical education (PE) instruction, as well as providing training for generalist classroom teachers. In the present study, a group of generalist teachers were interviewed…

  14. External Service Providers to the National Security Technology Incubator: Formalization of Relationships

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-04-30

    This report documents the formalization of relationships with external service providers in the development of the National Security Technology Incubator (NSTI). The technology incubator is being developed as part of the National Security Preparedness Project (NSPP), funded by a Department of Energy (DOE)/National Nuclear Security Administration (NNSA) grant. This report summarizes the process in developing and formalizing relationships with those service providers and includes a sample letter of cooperation executed with each provider.

  15. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE

    Science.gov (United States)

    Zahodne, Laura B.; Meyer, Oanh L.; Choi, Eunhee; Thomas, Michael L.; Willis, Sherry L.; Marsiske, Michael; Gross, Alden L.; Rebok, George W.; Parisi, Jeanine M.

    2015-01-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. PMID:26237116

  16. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE.

    Science.gov (United States)

    Zahodne, Laura B; Meyer, Oanh L; Choi, Eunhee; Thomas, Michael L; Willis, Sherry L; Marsiske, Michael; Gross, Alden L; Rebok, George W; Parisi, Jeanine M

    2015-09-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. (c) 2015 APA, all rights reserved).

  17. External Providers and Their Impact on Primary Physical Education in Aotearoa/New Zealand

    Science.gov (United States)

    Dyson, Ben; Gordon, Barrie; Cowan, Jackie; McKenzie, Allison

    2016-01-01

    Within Aotearoa/New Zealand primary schools, External Providers (EPs) have steadily increased their influence on physical education. The purpose of this study was to explore and interpret classroom teachers' perspectives of EPs in their primary school. The research team obtained questionnaire responses from 487 classroom teachers from 133…

  18. The working memory stroop effect: when internal representations clash with external stimuli.

    Science.gov (United States)

    Kiyonaga, Anastasia; Egner, Tobias

    2014-08-01

    Working memory (WM) has recently been described as internally directed attention, which implies that WM content should affect behavior exactly like an externally perceived and attended stimulus. We tested whether holding a color word in WM, rather than attending to it in the external environment, can produce interference in a color-discrimination task, which would mimic the classic Stroop effect. Over three experiments, the WM Stroop effect recapitulated core properties of the classic attentional Stroop effect, displaying equivalent congruency effects, additive contributions from stimulus- and response-level congruency, and susceptibility to modulation by the percentage of congruent and incongruent trials. Moreover, WM maintenance was inversely related to attentional demands during the WM delay between stimulus presentation and recall, with poorer memory performance following incongruent than congruent trials. Together, these results suggest that WM and attention rely on the same resources and operate over the same representations. © The Author(s) 2014.

  19. System of common usage on the base of external memory devices and the SM-3 computer

    International Nuclear Information System (INIS)

    Baluka, G.; Vasin, A.Yu.; Ermakov, V.A.; Zhukov, G.P.; Zimin, G.N.; Namsraj, Yu.; Ostrovnoj, A.I.; Savvateev, A.S.; Salamatin, I.M.; Yanovskij, G.Ya.

    1980-01-01

    An easily modified system of common usage on the base of external memories and a SM-3 minicomputer replacing some pulse analysers is described. The system has merits of PA and is more advantageous with regard to effectiveness of equipment using, the possibility of changing configuration and functions, the data protection against losses due to user errors and some failures, price of one registration channel, place occupied. The system of common usage is intended for the IBR-2 pulse reactor computing centre. It is designed using the SANPO system means for SM-3 computer [ru

  20. Descriptive study of external employee assistance program providers (EAP) in Japan.

    Science.gov (United States)

    Muto, Takashi; Haruyama, Yasuo; Higashi, Toshiaki

    2012-01-01

    The mental health problems of employees have become a major occupational health issue in Japan. External employee assistance program providers (EAP) have become important in mental health care for workers, but their activities are poorly documented. This descriptive study was undertaken to clarify the status and future tasks of EAP in Japan. The subjects were all EAP (n=27) registered in the Japanese Chapter of Employee Assistance Professionals Association. The questionnaire survey was conducted in January 2007. We received 13 replies, a response rate of 54.2%. Most EAP provided seminars, stress checks, stress management, counseling, and support for a return to work. The number of EAP contracted with small-scale enterprises was small. EAP communicated infrequently with companies. To promote the use of EAP, their advertising, education and training of staff, accumulation of scientific evidence, development of an official certification system for staff, and improvement of contents of EAP services were cited.

  1. Working memory as internal attention: toward an integrative account of internal and external selection processes.

    Science.gov (United States)

    Kiyonaga, Anastasia; Egner, Tobias

    2013-04-01

    Working memory (WM) and attention have been studied as separate cognitive constructs, although it has long been acknowledged that attention plays an important role in controlling the activation, maintenance, and manipulation of representations in WM. WM has, conversely, been thought of as a means of maintaining representations to voluntarily guide perceptual selective attention. It has more recently been observed, however, that the contents of WM can capture visual attention, even when such internally maintained representations are irrelevant, and often disruptive, to the immediate external task. Thus, the precise relationship between WM and attention remains unclear, but it appears that they may bidirectionally impact one another, whether or not internal representations are consistent with the external perceptual goals. This reciprocal relationship seems, further, to be constrained by limited cognitive resources to handle demands in either maintenance or selection. We propose here that the close relationship between WM and attention may be best described as a give-and-take interdependence between attention directed toward either actively maintained internal representations (traditionally considered WM) or external perceptual stimuli (traditionally considered selective attention), underpinned by their shared reliance on a common cognitive resource. Put simply, we argue that WM and attention should no longer be considered as separate systems or concepts, but as competing and influencing one another because they rely on the same limited resource. This framework can offer an explanation for the capture of visual attention by irrelevant WM contents, as well as a straightforward account of the underspecified relationship between WM and attention.

  2. Working Memory as Internal Attention: Toward an Integrative Account of Internal and External Selection Processes

    Science.gov (United States)

    Kiyonaga, Anastasia; Egner, Tobias

    2012-01-01

    Working memory (WM) and attention have been studied as separate cognitive constructs, although it has long been acknowledged that attention plays an important role in controlling the activation, maintenance, and manipulation of representations in WM. WM has, conversely, been thought of as a means of maintaining representations to voluntarily guide perceptual selective attention. It has more recently been observed, however, that the contents of WM can capture visual attention, even when such internally maintained representations are irrelevant, and often disruptive, to the immediate external task. Thus the precise relationship between WM and attention remains unclear, but it appears that they may bi-directionally impact one another, whether or not internal representations are consistent with external perceptual goals. This reciprocal relationship seems, further, to be constrained by limited cognitive resources to handle demands in either maintenance or selection. We propose here that the close relationship between WM and attention may be best described as a give-and-take interdependence between attention directed toward actively maintained internal representations (traditionally considered WM) versus external perceptual stimuli (traditionally considered selective attention), underpinned by their shared reliance on a common cognitive resource. Put simply, we argue that WM and attention should no longer be considered as separate systems or concepts, but as competing and impacting one another because they rely on the same limited resource. This framework can offer an explanation for the capture of visual attention by irrelevant WM contents, as well as a straightforward account of the underspecified relationship between WM and attention. PMID:23233157

  3. Enhanced jump performance when providing augmented feedback compared to an external or internal focus of attention.

    Science.gov (United States)

    Keller, Martin; Lauber, Benedikt; Gottschalk, Marius; Taube, Wolfgang

    2015-01-01

    Factors such as an external focus of attention (EF) and augmented feedback (AF) have been shown to improve performance. However, the efficacy of providing AF to enhance motor performance has never been compared with the effects of an EF or an internal focus of attention (IF). Therefore, the aim of the present study was to identify which of the three conditions (AF, EF or IF) leads to the highest performance in a countermovement jump (CMJ). Nineteen volunteers performed 12 series of 8 maximum CMJs. Changes in jump height between conditions and within the series were analysed. Jump heights differed between conditions (P jump heights at the end of the series in AF (+1.60%) and lower jump heights at the end of the series in EF (-1.79%) and IF (-1.68%) were observed. Muscle activity did not differ between conditions. The differences between conditions and within the series provide evidence that AF leads to higher performance and better progression within one series than EF and IF. Consequently, AF seems to outperform EF and IF when maximising jump height.

  4. A New Local Bipolar Autoassociative Memory Based on External Inputs of Discrete Recurrent Neural Networks With Time Delay.

    Science.gov (United States)

    Zhou, Caigen; Zeng, Xiaoqin; Luo, Chaomin; Zhang, Huaguang

    In this paper, local bipolar auto-associative memories are presented based on discrete recurrent neural networks with a class of gain type activation function. The weight parameters of neural networks are acquired by a set of inequalities without the learning procedure. The global exponential stability criteria are established to ensure the accuracy of the restored patterns by considering time delays and external inputs. The proposed methodology is capable of effectively overcoming spurious memory patterns and achieving memory capacity. The effectiveness, robustness, and fault-tolerant capability are validated by simulated experiments.In this paper, local bipolar auto-associative memories are presented based on discrete recurrent neural networks with a class of gain type activation function. The weight parameters of neural networks are acquired by a set of inequalities without the learning procedure. The global exponential stability criteria are established to ensure the accuracy of the restored patterns by considering time delays and external inputs. The proposed methodology is capable of effectively overcoming spurious memory patterns and achieving memory capacity. The effectiveness, robustness, and fault-tolerant capability are validated by simulated experiments.

  5. Maternal depression and trajectories of child internalizing and externalizing problems: the roles of child decision making and working memory.

    Science.gov (United States)

    Flouri, E; Ruddy, A; Midouhas, E

    2017-04-01

    Maternal depression may affect the emotional/behavioural outcomes of children with normal neurocognitive functioning less severely than it does those without. To guide prevention and intervention efforts, research must specify which aspects of a child's cognitive functioning both moderate the effect of maternal depression and are amenable to change. Working memory and decision making may be amenable to change and are so far unexplored as moderators of this effect. Our sample was 17 160 Millennium Cohort Study children. We analysed trajectories of externalizing (conduct and hyperactivity) and internalizing (emotional and peer) problems, measured with the Strengths and Difficulties Questionnaire at the ages 3, 5, 7 and 11 years, using growth curve models. We characterized maternal depression, also time-varying at these ages, by a high score on the K6. Working memory was measured with the Cambridge Neuropsychological Test Automated Battery Spatial Working Memory Task, and decision making (risk taking and quality of decision making) with the Cambridge Gambling Task, both at age 11 years. Maternal depression predicted both the level and the growth of problems. Risk taking and poor-quality decision making were related positively to externalizing and non-significantly to internalizing problems. Poor working memory was related to both problem types. Neither decision making nor working memory explained the effect of maternal depression on child internalizing/externalizing problems. Importantly, risk taking amplified the effect of maternal depression on internalizing problems, and poor working memory that on internalizing and conduct problems. Impaired decision making and working memory in children amplify the adverse effect of maternal depression on, particularly, internalizing problems.

  6. Development and validation of the ExPRESS instrument for primary health care providers' evaluation of external supervision.

    Science.gov (United States)

    Schriver, Michael; Cubaka, Vincent Kalumire; Vedsted, Peter; Besigye, Innocent; Kallestrup, Per

    2018-01-01

    External supervision of primary health care facilities to monitor and improve services is common in low-income countries. Currently there are no tools to measure the quality of support in external supervision in these countries. To develop a provider-reported instrument to assess the support delivered through external supervision in Rwanda and other countries. "External supervision: Provider Evaluation of Supervisor Support" (ExPRESS) was developed in 18 steps, primarily in Rwanda. Content validity was optimised using systematic search for related instruments, interviews, translations, and relevance assessments by international supervision experts as well as local experts in Nigeria, Kenya, Uganda and Rwanda. Construct validity and reliability were examined in two separate field tests, the first using exploratory factor analysis and a test-retest design, the second for confirmatory factor analysis. We included 16 items in section A ('The most recent experience with an external supervisor'), and 13 items in section B ('The overall experience with external supervisors'). Item-content validity index was acceptable. In field test I, test-retest had acceptable kappa values and exploratory factor analysis suggested relevant factors in sections A and B used for model hypotheses. In field test II, models were tested by confirmatory factor analysis fitting a 4-factor model for section A, and a 3-factor model for section B. ExPRESS is a promising tool for evaluation of the quality of support of primary health care providers in external supervision of primary health care facilities in resource-constrained settings. ExPRESS may be used as specific feedback to external supervisors to help identify and address gaps in the supervision they provide. Further studies should determine optimal interpretation of scores and the number of respondents needed per supervisor to obtain precise results, as well as test the functionality of section B.

  7. The impact of cognitive control, incentives, and working memory load on the P3 responses of externalizing prisoners.

    Science.gov (United States)

    Baskin-Sommers, Arielle R; Krusemark, Elizabeth A; Curtin, John J; Lee, Christopher; Vujnovich, Aleice; Newman, Joseph P

    2014-02-01

    The P3 amplitude reduction is one of the most common correlates of externalizing. However, few studies have used experimental manipulations designed to challenge different cognitive functions in order to clarify the processes that impact this reduction. To examine factors moderating P3 amplitude in trait externalizing, we administered an n-back task that manipulated cognitive control demands, working memory load, and incentives to a sample of male offenders. Offenders with high trait externalizing scores did not display a global reduction in P3 amplitude. Rather, the negative association between trait externalizing and P3 amplitude was specific to trials involving inhibition of a dominant response during infrequent stimuli, in the context of low working memory load, and incentives for performance. In addition, we discuss the potential implications of these findings for externalizing-related psychopathologies. The results complement and expand previous work on the process-level dysfunction contributing to externalizing-related deficits in P3. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Externally induced frontoparietal synchronization modulates network dynamics and enhances working memory performance.

    Science.gov (United States)

    Violante, Ines R; Li, Lucia M; Carmichael, David W; Lorenz, Romy; Leech, Robert; Hampshire, Adam; Rothwell, John C; Sharp, David J

    2017-03-14

    Cognitive functions such as working memory (WM) are emergent properties of large-scale network interactions. Synchronisation of oscillatory activity might contribute to WM by enabling the coordination of long-range processes. However, causal evidence for the way oscillatory activity shapes network dynamics and behavior in humans is limited. Here we applied transcranial alternating current stimulation (tACS) to exogenously modulate oscillatory activity in a right frontoparietal network that supports WM. Externally induced synchronization improved performance when cognitive demands were high. Simultaneously collected fMRI data reveals tACS effects dependent on the relative phase of the stimulation and the internal cognitive processing state. Specifically, synchronous tACS during the verbal WM task increased parietal activity, which correlated with behavioral performance. Furthermore, functional connectivity results indicate that the relative phase of frontoparietal stimulation influences information flow within the WM network. Overall, our findings demonstrate a link between behavioral performance in a demanding WM task and large-scale brain synchronization.

  9. Functional magnetic resonance imaging study of external source memory and its relation to cognitive insight in non-clinical subjects.

    Science.gov (United States)

    Buchy, Lisa; Hawco, Colin; Bodnar, Michael; Izadi, Sarah; Dell'Elce, Jennifer; Messina, Katrina; Lepage, Martin

    2014-09-01

    Previous research has linked cognitive insight (a measure of self-reflectiveness and self-certainty) in psychosis with neurocognitive and neuroanatomical disturbances in the fronto-hippocampal neural network. The authors' goal was to use functional magnetic resonance imaging (fMRI) to investigate the neural correlates of cognitive insight during an external source memory paradigm in non-clinical subjects. At encoding, 24 non-clinical subjects travelled through a virtual city where they came across 20 separate people, each paired with a unique object in a distinct location. fMRI data were then acquired while participants viewed images of the city, and completed source recognition memory judgments of where and with whom objects were seen, which is known to involve prefrontal cortex. Cognitive insight was assessed with the Beck Cognitive Insight Scale. External source memory was associated with neural activity in a widespread network consisting of frontal cortex, including ventrolateral prefrontal cortex (VLPFC), temporal and occipital cortices. Activation in VLPFC correlated with higher self-reflectiveness and activation in midbrain correlated with lower self-certainty during source memory attributions. Neither self-reflectiveness nor self-certainty significantly correlated with source memory accuracy. By means of virtual reality and in the context of an external source memory paradigm, the study identified a preliminary functional neural basis for cognitive insight in the VLPFC in healthy people that accords with our fronto-hippocampal theoretical model as well as recent neuroimaging data in people with psychosis. The results may facilitate the understanding of the role of neural mechanisms in psychotic disorders associated with cognitive insight distortions. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  10. Evaluation of External Memory Access Performance on a High-End FPGA Hybrid Computer

    Directory of Open Access Journals (Sweden)

    Konstantinos Kalaitzis

    2016-10-01

    Full Text Available The motivation of this research was to evaluate the main memory performance of a hybrid super computer such as the Convey HC-x, and ascertain how the controller performs in several access scenarios, vis-à-vis hand-coded memory prefetches. Such memory patterns are very useful in stencil computations. The theoretical bandwidth of the memory of the Convey is compared with the results of our measurements. The accurate study of the memory subsystem is particularly useful for users when they are developing their application-specific personality. Experiments were performed to measure the bandwidth between the coprocessor and the memory subsystem. The experiments aimed mainly at measuring the reading access speed of the memory from Application Engines (FPGAs. Different ways of accessing data were used in order to find the most efficient way to access memory. This way was proposed for future work in the Convey HC-x. When performing a series of accesses to memory, non-uniform latencies occur. The Memory Controller of the Convey HC-x in the coprocessor attempts to cover this latency. We measure memory efficiency as a ratio of the number of memory accesses and the number of execution cycles. The result of this measurement converges to one in most cases. In addition, we performed experiments with hand-coded memory accesses. The analysis of the experimental results shows how the memory subsystem and Memory Controllers work. From this work we conclude that the memory controllers do an excellent job, largely because (transparently to the user they seem to cache large amounts of data, and hence hand-coding is not needed in most situations.

  11. Implementation of client versus care-provider strategies to improve external cephalic version rates: a cluster randomized controlled trial

    NARCIS (Netherlands)

    Vlemmix, Floortje; Rosman, Ageeth N.; Rijnders, Marlies E.; Beuckens, Antje; Opmeer, Brent C.; Mol, Ben W. J.; Kok, Marjolein; Fleuren, Margot A. H.

    2015-01-01

    To determine the effectiveness of a client or care-provider strategy to improve the implementation of external cephalic version. Cluster randomized controlled trial. Twenty-five clusters; hospitals and their referring midwifery practices randomly selected in the Netherlands. Singleton breech

  12. Implementation of client versus care-provider strategies to improve external cephalic version rates: a cluster randomized controlled trial

    NARCIS (Netherlands)

    Vlemmix, F.; Rosman, A.N.; Rijnders, M.E.; Beuckens, A.; Opmeer, B.C.; Mol, B.W.J.; Kok, M.; Fleuren, M.A.H.

    2015-01-01

    Onjective: To determine the effectiveness of a client or care-provider strategy to improve the implementation of external cephalic version. Design: Cluster randomized controlled trial.Setting: Twenty-five clusters; hospitals and their referring midwifery practices randomly selected in the

  13. External Providers' Sexuality Education Teaching and Pedagogies for Primary School Students in Grade 1 to Grade 7

    Science.gov (United States)

    Goldman, Juliette D. G.

    2011-01-01

    Many primary school teachers avoid teaching sexuality education. In light of the earlier maturing of both boys and girls, and the educationally and personally significant effects of their experience of puberty, this is unfair to children. In response to this avoidance, however, some schools employ external providers of sexuality education, who…

  14. Contralateral delay activity provides a neural measure of the number of representations in visual working memory.

    Science.gov (United States)

    Ikkai, Akiko; McCollough, Andrew W; Vogel, Edward K

    2010-04-01

    Visual working memory (VWM) helps to temporarily represent information from the visual environment and is severely limited in capacity. Recent work has linked various forms of neural activity to the ongoing representations in VWM. One piece of evidence comes from human event-related potential studies, which find a sustained contralateral negativity during the retention period of VWM tasks. This contralateral delay activity (CDA) has previously been shown to increase in amplitude as the number of memory items increases, up to the individual's working memory capacity limit. However, significant alternative hypotheses remain regarding the true nature of this activity. Here we test whether the CDA is modulated by the perceptual requirements of the memory items as well as whether it is determined by the number of locations that are being attended within the display. Our results provide evidence against these two alternative accounts and instead strongly support the interpretation that this activity reflects the current number of objects that are being represented in VWM.

  15. Implementation of client versus care-provider strategies to improve external cephalic version rates: a cluster randomized controlled trial.

    Science.gov (United States)

    Vlemmix, Floortje; Rosman, Ageeth N; Rijnders, Marlies E; Beuckens, Antje; Opmeer, Brent C; Mol, Ben W J; Kok, Marjolein; Fleuren, Margot A H

    2015-05-01

    To determine the effectiveness of a client or care-provider strategy to improve the implementation of external cephalic version. Cluster randomized controlled trial. Twenty-five clusters; hospitals and their referring midwifery practices randomly selected in the Netherlands. Singleton breech presentation from 32 weeks of gestation onwards. We randomized clusters to a client strategy (written information leaflets and decision aid), a care-provider strategy (1-day counseling course focused on knowledge and counseling skills), a combined client and care-provider strategy and care-as-usual strategy. We performed an intention-to-treat analysis. Rate of external cephalic version in various strategies. Secondary outcomes were the percentage of women counseled and opting for a version attempt. The overall implementation rate of external cephalic version was 72% (1169 of 1613 eligible clients) with a range between clusters of 8-95%. Neither the client strategy (OR 0.8, 95% CI 0.4-1.5) nor the care-provider strategy (OR 1.2, 95% CI 0.6-2.3) showed significant improvements. Results were comparable when we limited the analysis to those women who were actually offered intervention (OR 0.6, 95% CI 0.3-1.4 and OR 2.0, 95% CI 0.7-4.5). Neither a client nor a care-provider strategy improved the external cephalic version implementation rate for breech presentation, neither with regard to the number of version attempts offered nor the number of women accepting the procedure. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

  16. Scaling Techniques for Massive Scale-Free Graphs in Distributed (External) Memory

    KAUST Repository

    Pearce, Roger; Gokhale, Maya; Amato, Nancy M.

    2013-01-01

    We present techniques to process large scale-free graphs in distributed memory. Our aim is to scale to trillions of edges, and our research is targeted at leadership class supercomputers and clusters with local non-volatile memory, e.g., NAND Flash

  17. No deficits in nonverbal memory, metamemory and internal as well as external source memory in obsessive-compulsive disorder (OCD).

    Science.gov (United States)

    Moritz, Steffen; Ruhe, Claudia; Jelinek, Lena; Naber, Dieter

    2009-04-01

    A large body of literature suggests that some symptoms of obsessive-compulsive disorder (OCD) result from mnemonic dysfunctions. The present study tested various formulations of the memory deficit hypothesis considering important moderators, such as depression and response slowing. Thirty-two OCD patients and 32 healthy controls were presented verbal or nonverbal instructions for actions (e.g. simple gestures). These actions should either be performed or imagined. For recognition, previously presented as well as novel actions were displayed. Decisions had to be made whether an action was previously displayed (verbally vs. nonverbally) or not and whether an action was performed or imagined (internal source memory). Moreover, both judgments required confidence ratings. Groups did not differ in memory accuracy and metamemory for verbally presented material. Patients displayed some impairment for nonverbally presented material and imagined instructions, which, however, could be fully accounted for by response slowing and depressive symptoms. The study challenges the view that primary memory deficits underlie OCD or any of its subtypes. We claim that research should move forward from the mere study of objective impairment to the assessment of cognitive performance in conjunction with personality traits such as inflated responsibility.

  18. External and Internal Impact on Soviet Memorial Landscape Development by THE World War II

    Directory of Open Access Journals (Sweden)

    Alexandra Cherkasski

    2012-11-01

    Full Text Available The World War II led to serious casualties and left deep scars / wounds of memory. As the victory over occupation regime was glorified, honored and starting from 1965 was widely celebrated at national level, there was a great gap between official and personal memory of war. Monuments are one of the forms of living examples of the past and thus are reliable sources for the study of different epochs and Zeitgeist / spirit of time and their changes. This article considers the development of Soviet memorial landscape by the World War II starting from the war termination to the Soviet Union collapse. Special attention is attached to internal political and international views / interpretations and development with respect to victims of war. In other words, the process of different groups of war victims exclusion and inclusion in Soviet collective memory under the influence of internal political and foreign political interests symbiosis. And, as a result, resultant attitude towards memorial places.

  19. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

    Directory of Open Access Journals (Sweden)

    Christof eKuhbandner

    2016-02-01

    Full Text Available Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one third of the words were tested and one third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After one week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  20. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

    Science.gov (United States)

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  1. Internalizing versus Externalizing Control: Different Ways to Perform a Time-Based Prospective Memory Task

    Science.gov (United States)

    Huang, Tracy; Loft, Shayne; Humphreys, Michael S.

    2014-01-01

    "Time-based prospective memory" (PM) refers to performing intended actions at a future time. Participants with time-based PM tasks can be slower to perform ongoing tasks (costs) than participants without PM tasks because internal control is required to maintain the PM intention or to make prospective-timing estimates. However, external…

  2. Prospective Memory in an Air Traffic Control Simulation: External Aids that Signal when to Act

    Science.gov (United States)

    Loft, Shayne; Smith, Rebekah E.; Bhaskara, Adella

    2011-01-01

    At work and in our personal life we often need to remember to perform intended actions at some point in the future, referred to as Prospective Memory. Individuals sometimes forget to perform intentions in safety-critical work contexts. Holding intentions can also interfere with ongoing tasks. We applied theories and methods from the experimental…

  3. When do anterior external or internal fixators provide additional stability in an unstable (Tile C) pelvic fracture? A biomechanical study.

    Science.gov (United States)

    Mcdonald, E; Theologis, A A; Horst, P; Kandemir, U; Pekmezci, M

    2015-12-01

    This study aimed at evaluating the additional stability that is provided by anterior external and internal fixators in an unstable pelvic fracture model (OTA 61-C). An unstable pelvic fracture (OTA 61-C) was created in 27 synthetic pelves by making a 5-mm gap through the sacral foramina (posterior injury) and an ipsilateral pubic rami fracture (anterior injury). The posterior injury was fixed with either a single iliosacral (IS) screw, a single trans-iliac, trans-sacral (TS) screw, or two iliosacral screws (S1S2). Two anterior fixation techniques were utilized: external fixation (Ex-Fix) and supra-acetabular external fixation and internal fixation (In-Fix); supra-acetabular pedicle screws connected with a single subcutaneous spinal rod. The specimens were tested using a nondestructive single-leg stance model. Peak-to-peak (P2P) displacement and rotation and conditioning displacement (CD) were calculated. The Ex-Fix group failed in 83.3 % of specimens with concomitant single-level posterior fixation (Total: 15/18-7 of 9 IS fixation, 8 of 9 TS fixation), and 0 % (0/9) of specimens with concomitant two-level (S1S2) posterior fixation. All specimens with the In-Fix survived testing except for two specimens treated with In-Fix combined with IS fixation. Trans-sacral fixation had higher pubic rotation and greater sacral and pubic displacement than S1S2 (p < 0.05). Rotation of the pubis and sacrum was not different between In-Fix constructs combined with single-level IS and TS fixation. In this model of an unstable pelvic fracture (OTA 61-C), anterior fixation with an In-Fix was biomechanically superior to an anterior Ex-Fix in the setting of single-level posterior fixation. There was no biomechanical difference between the In-Fix and Ex-Fix when each was combined with two levels of posterior sacral fixation.

  4. Providing Memory Management Abstraction for Self-Reconfigurable Video Processing Platforms

    Directory of Open Access Journals (Sweden)

    Kurt Franz Ackermann

    2009-01-01

    Full Text Available This paper presents a concept for an SDRAM controller targeting video processing platforms with dynamically reconfigurable processing units (RPUs. A priority-arbitration algorithm provides the required QoS and supports high bit-rate data streaming of multiple clients. Conforming to common video data structures the controller organizes the memory in partitions, frames, lines, and pixels. The raised level of abstraction drastically reduces the complexity of clients' addressing logic. Its uniform interface structure facilitates instantiations in systems with various clients. In addition to SDRAM controllers for regular applications, special demands of reconfigurable platforms have to be satisfied. The aim of this work is to minimize the number of required bus macros leading to relaxed place and route constraints and reducing the number of critical design paths. A suitable interface protocol is presented, and fundamental implementation issues are outlined.

  5. Family child care providers' self-perceived role in obesity prevention: working with children, parents, and external influences.

    Science.gov (United States)

    Rosenthal, Marjorie S; Crowley, Angela A; Curry, Leslie

    2013-01-01

    To describe the perspective and strategies of family child care providers (FCCPs) to reduce children's suboptimal weight trajectories. In-person, in-depth interviews with FCCPs. Family child care homes. Seventeen FCCPs caring for children 6 weeks to 9 years old; 94% caring for children paying with a state subsidy. Strategies of FCCP to reduce children's suboptimal weight trajectories. Constant comparative method of qualitative data analysis. Family child care providers described 3 core strategies: (1) improving children's behavior, (2) engaging and educating parents, and (3) leveraging influences external to their relationship with parents to effect positive change and to avoid parental conflict. These strategies were framed within their knowledge of child development, parental communication, and community services. The findings suggest that FCCPs' role in obesity prevention may be framed within knowledge that may be commonly expected of a child care provider. Partnerships between public health policy makers and FCCP may reduce obesigenic environments by employing training and resources that link obesity prevention and child care provider expertise. Copyright © 2013 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  6. Bi-periodicity evoked by periodic external inputs in delayed Cohen-Grossberg-type bidirectional associative memory networks

    Science.gov (United States)

    Cao, Jinde; Wang, Yanyan

    2010-05-01

    In this paper, the bi-periodicity issue is discussed for Cohen-Grossberg-type (CG-type) bidirectional associative memory (BAM) neural networks (NNs) with time-varying delays and standard activation functions. It is shown that the model considered in this paper has two periodic orbits located in saturation regions and they are locally exponentially stable. Meanwhile, some conditions are derived to ensure that, in any designated region, the model has a locally exponentially stable or globally exponentially attractive periodic orbit located in it. As a special case of bi-periodicity, some results are also presented for the system with constant external inputs. Finally, four examples are given to illustrate the effectiveness of the obtained results.

  7. Bi-periodicity evoked by periodic external inputs in delayed Cohen-Grossberg-type bidirectional associative memory networks

    International Nuclear Information System (INIS)

    Cao Jinde; Wang Yanyan

    2010-01-01

    In this paper, the bi-periodicity issue is discussed for Cohen-Grossberg-type (CG-type) bidirectional associative memory (BAM) neural networks (NNs) with time-varying delays and standard activation functions. It is shown that the model considered in this paper has two periodic orbits located in saturation regions and they are locally exponentially stable. Meanwhile, some conditions are derived to ensure that, in any designated region, the model has a locally exponentially stable or globally exponentially attractive periodic orbit located in it. As a special case of bi-periodicity, some results are also presented for the system with constant external inputs. Finally, four examples are given to illustrate the effectiveness of the obtained results.

  8. Scaling Techniques for Massive Scale-Free Graphs in Distributed (External) Memory

    KAUST Repository

    Pearce, Roger

    2013-05-01

    We present techniques to process large scale-free graphs in distributed memory. Our aim is to scale to trillions of edges, and our research is targeted at leadership class supercomputers and clusters with local non-volatile memory, e.g., NAND Flash. We apply an edge list partitioning technique, designed to accommodate high-degree vertices (hubs) that create scaling challenges when processing scale-free graphs. In addition to partitioning hubs, we use ghost vertices to represent the hubs to reduce communication hotspots. We present a scaling study with three important graph algorithms: Breadth-First Search (BFS), K-Core decomposition, and Triangle Counting. We also demonstrate scalability on BG/P Intrepid by comparing to best known Graph500 results. We show results on two clusters with local NVRAM storage that are capable of traversing trillion-edge scale-free graphs. By leveraging node-local NAND Flash, our approach can process thirty-two times larger datasets with only a 39% performance degradation in Traversed Edges Per Second (TEPS). © 2013 IEEE.

  9. Familiar real-world spatial cues provide memory benefits in older and younger adults.

    Science.gov (United States)

    Robin, Jessica; Moscovitch, Morris

    2017-05-01

    Episodic memory, future thinking, and memory for scenes have all been proposed to rely on the hippocampus, and evidence suggests that these all decline in healthy aging. Despite this age-related memory decline, studies examining the effects of context reinstatement on episodic memory have demonstrated that reinstating elements of the encoding context of an event leads to better memory retrieval in both younger and older adults. The current study was designed to test whether more familiar, real-world contexts, such as locations that participants visited often, would improve the detail richness and vividness of memory for scenes, autobiographical events, and imagination of future events in young and older adults. The predicted age-related decline in internal details across all 3 conditions was accompanied by persistent effects of contextual familiarity, in which a more familiar spatial context led to increased detail and vividness of remembered scenes, autobiographical events, and, to some extent, imagined future events. This study demonstrates that autobiographical memory, imagination of the future, and scene memory are similarly affected by aging, and all benefit from being associated with more familiar (real-world) contexts, illustrating the stability of contextual reinstatement effects on memory throughout the life span. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Task-evoked pupillometry provides a window into the development of short-term memory capacity

    Science.gov (United States)

    Johnson, Elizabeth L.; Miller Singley, Alison T.; Peckham, Andrew D.; Johnson, Sheri L.; Bunge, Silvia A.

    2014-01-01

    The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM. PMID:24659980

  11. Task-evoked pupillometry provides a window into the development of short-term memory capacity.

    Science.gov (United States)

    Johnson, Elizabeth L; Miller Singley, Alison T; Peckham, Andrew D; Johnson, Sheri L; Bunge, Silvia A

    2014-01-01

    The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

  12. SU-E-T-571: Newly Emerging Integrated Transmission Detector Systems Provide Online Quality Assurance of External Beam Radiation Therapy

    International Nuclear Information System (INIS)

    Hoffman, D; Chung, E; Hess, C; Stern, R; Benedict, S

    2015-01-01

    Purpose: Two newly emerging transmission detectors positioned upstream from the patient have been evaluated for online quality assurance of external beam radiotherapy. The prototype for the Integral Quality Monitor (IQM), developed by iRT Systems GmbH (Koblenz, Germany) is a large-area ion chamber mounted on the linac accessory tray to monitor photon fluence, energy, beam shape, and gantry position during treatment. The ion chamber utilizes a thickness gradient which records variable response dependent on beam position. The prototype of Delta4 Discover™, developed by ScandiDos (Uppsala, Sweden) is a linac accessory tray mounted 4040 diode array that measures photon fluence during patient treatment. Both systems are employable for patient specific QA prior to treatment delivery. Methods: Our institution evaluated the reproducibility of measurements using various beam types, including VMAT treatment plans with both the IQM ion chamber and the Delta4 Discover diode array. Additionally, the IQM’s effect on photon fluence, dose response, simulated beam error detection, and the accuracy of the integrated barometer, thermometer, and inclinometer were characterized. The evaluated photon beam errors are based on the annual tolerances specified in AAPM TG-142. Results: Repeated VMAT treatments were measured with 0.16% reproducibility by the IQM and 0.55% reproducibility by the Delta4 Discover. The IQM attenuated 6, 10, and 15 MV photon beams by 5.43±0.02%, 4.60±0.02%, and 4.21±0.03% respectively. Photon beam profiles were affected <1.5% in the non-penumbra regions. The IQM’s ion chamber’s dose response was linear and the thermometer, barometer, and inclinometer agreed with other calibrated devices. The device detected variations in monitor units delivered (1%), field position (3mm), single MLC leaf positions (13mm), and photon energy. Conclusion: We have characterized two new transmissions detector systems designed to provide in-vivo like measurements upstream

  13. SU-E-T-571: Newly Emerging Integrated Transmission Detector Systems Provide Online Quality Assurance of External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D; Chung, E; Hess, C; Stern, R; Benedict, S [UC Davis Cancer Center, Sacramento, CA (United States)

    2015-06-15

    Purpose: Two newly emerging transmission detectors positioned upstream from the patient have been evaluated for online quality assurance of external beam radiotherapy. The prototype for the Integral Quality Monitor (IQM), developed by iRT Systems GmbH (Koblenz, Germany) is a large-area ion chamber mounted on the linac accessory tray to monitor photon fluence, energy, beam shape, and gantry position during treatment. The ion chamber utilizes a thickness gradient which records variable response dependent on beam position. The prototype of Delta4 Discover™, developed by ScandiDos (Uppsala, Sweden) is a linac accessory tray mounted 4040 diode array that measures photon fluence during patient treatment. Both systems are employable for patient specific QA prior to treatment delivery. Methods: Our institution evaluated the reproducibility of measurements using various beam types, including VMAT treatment plans with both the IQM ion chamber and the Delta4 Discover diode array. Additionally, the IQM’s effect on photon fluence, dose response, simulated beam error detection, and the accuracy of the integrated barometer, thermometer, and inclinometer were characterized. The evaluated photon beam errors are based on the annual tolerances specified in AAPM TG-142. Results: Repeated VMAT treatments were measured with 0.16% reproducibility by the IQM and 0.55% reproducibility by the Delta4 Discover. The IQM attenuated 6, 10, and 15 MV photon beams by 5.43±0.02%, 4.60±0.02%, and 4.21±0.03% respectively. Photon beam profiles were affected <1.5% in the non-penumbra regions. The IQM’s ion chamber’s dose response was linear and the thermometer, barometer, and inclinometer agreed with other calibrated devices. The device detected variations in monitor units delivered (1%), field position (3mm), single MLC leaf positions (13mm), and photon energy. Conclusion: We have characterized two new transmissions detector systems designed to provide in-vivo like measurements upstream

  14. Task-evoked pupillometry provides a window into the development of short-term memory capacity

    Directory of Open Access Journals (Sweden)

    Elizabeth L. Johnson

    2014-03-01

    Full Text Available The capacity to keep multiple items in short-term memory (STM improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.5 years and adults (n = 54, mean age = 27.5 years performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM Overload task, after which the adults’ pupils continued to dilate and the children’s began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage attention from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM Overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

  15. Liver-primed memory T cells generated under noninflammatory conditions provide anti-infectious immunity.

    Science.gov (United States)

    Böttcher, Jan P; Schanz, Oliver; Wohlleber, Dirk; Abdullah, Zeinab; Debey-Pascher, Svenja; Staratschek-Jox, Andrea; Höchst, Bastian; Hegenbarth, Silke; Grell, Jessica; Limmer, Andreas; Atreya, Imke; Neurath, Markus F; Busch, Dirk H; Schmitt, Edgar; van Endert, Peter; Kolanus, Waldemar; Kurts, Christian; Schultze, Joachim L; Diehl, Linda; Knolle, Percy A

    2013-03-28

    Development of CD8(+) T cell (CTL) immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs) matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling through the TCR, CD28, and IL-12R and controlled bacterial and viral infections. Gene expression profiling identified liver-primed T cells as a distinct Neuropilin-1(+) memory population. Generation of liver-primed memory T cells may prevent pathogens that avoid DC maturation by innate immune escape from also escaping adaptive immunity through attrition of the T cell repertoire. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Liver-Primed Memory T Cells Generated under Noninflammatory Conditions Provide Anti-infectious Immunity

    Directory of Open Access Journals (Sweden)

    Jan P. Böttcher

    2013-03-01

    Full Text Available Development of CD8+ T cell (CTL immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling through the TCR, CD28, and IL-12R and controlled bacterial and viral infections. Gene expression profiling identified liver-primed T cells as a distinct Neuropilin-1+ memory population. Generation of liver-primed memory T cells may prevent pathogens that avoid DC maturation by innate immune escape from also escaping adaptive immunity through attrition of the T cell repertoire.

  17. Memory

    Science.gov (United States)

    ... it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few ...

  18. The effect of internal and external stress on two-way shape-memory behaviour in Co49Ni21.6Ga29.4 single crystals

    International Nuclear Information System (INIS)

    Liu, G D; Dai, X F; Luo, H Z; Liu, H Y; Meng, F B; Li, Y; Yu, X; Chen, J L; Wu, G H

    2011-01-01

    The effect of the internal stress on the two-way shape memory in Co 49 Ni 21.6 Ga 29.4 single crystals has been investigated. We found that the internal stress generated natively by the solidifying process works as a tensile force along the growth direction. Applying different compressive pre-stresses along the [0 0 1] direction, the shape-memory strain can be continuously changed from +1.0% to -2.3%. In the [1 1 0] direction, the strain monotonically increases from -2.0% to -4.0% due to a strong detwinning produced by the consistent effect of the external and internal stresses.

  19. Models Provide Specificity: Testing a Proposed Mechanism of Visual Working Memory Capacity Development

    Science.gov (United States)

    Simmering, Vanessa R.; Patterson, Rebecca

    2012-01-01

    Numerous studies have established that visual working memory has a limited capacity that increases during childhood. However, debate continues over the source of capacity limits and its developmental increase. Simmering (2008) adapted a computational model of spatial cognitive development, the Dynamic Field Theory, to explain not only the source…

  20. Approaches to the mechanisms of song memorization and singing provide evidence for a procedural memory

    OpenAIRE

    Hultsch,Henrike; Todt,Dietmar

    2004-01-01

    There is growing evidence that, during song learning, birds do not only acquire 'what to sing' (the inventory of behavior), but also 'how to sing' (the singing program), including order-features of song sequencing. Common Nightingales Luscinia megarhynchos acquire such serial information by segmenting long strings of heard songs into smaller subsets or packages, by a process reminiscent of the chunking of information as a coding mechanism in short term memory. Here we report three tutoring ex...

  1. Support Provided to the External Tank (ET) Project on the Use of Statistical Analysis for ET Certification Consultation Position Paper

    Science.gov (United States)

    Null, Cynthia H.

    2009-01-01

    In June 2004, the June Space Flight Leadership Council (SFLC) assigned an action to the NASA Engineering and Safety Center (NESC) and External Tank (ET) project jointly to characterize the available dataset [of defect sizes from dissections of foam], identify resultant limitations to statistical treatment of ET as-built foam as part of the overall thermal protection system (TPS) certification, and report to the Program Requirements Change Board (PRCB) and SFLC in September 2004. The NESC statistics team was formed to assist the ET statistics group in August 2004. The NESC's conclusions are presented in this report.

  2. Approaches to the mechanisms of song memorization and singing provide evidence for a procedural memory

    Directory of Open Access Journals (Sweden)

    Hultsch Henrike

    2004-01-01

    Full Text Available There is growing evidence that, during song learning, birds do not only acquire 'what to sing' (the inventory of behavior, but also 'how to sing' (the singing program, including order-features of song sequencing. Common Nightingales Luscinia megarhynchos acquire such serial information by segmenting long strings of heard songs into smaller subsets or packages, by a process reminiscent of the chunking of information as a coding mechanism in short term memory. Here we report three tutoring experiments on nightingales that examined whether such 'chunking' was susceptible to experimental cueing. The experiments tested whether (1 'temporal phrasing' (silent intersong intervals spaced out at particular positions of a tutored string, or (2 'stimulus novelty' (groups of novel song-types added to a basic string, or (3 'pattern similarity' in the phonetic structure of songs (here: sharing of song initials would induce package boundaries (or chunking at the manipulated sequential positions. The results revealed cueing effects in experiments (1 and (2 but not in experiment (3. The finding that birds used temporal variables as cues for chunking does not require the assumption that package formation is a cognitive strategy. Rather, it points towards a mechanism of procedural memory operating in the song acquisition of birds.

  3. Approaches to the mechanisms of song memorization and singing provide evidence for a procedural memory.

    Science.gov (United States)

    Hultsch, Henrike; Todt, Dietmar

    2004-06-01

    There is growing evidence that, during song learning, birds do not only acquire 'what to sing' (the inventory of behavior), but also 'how to sing' (the singing program), including order-features of song sequencing. Common Nightingales Luscinia megarhynchos acquire such serial information by segmenting long strings of heard songs into smaller subsets or packages, by a process reminiscent of the chunking of information as a coding mechanism in short term memory. Here we report three tutoring experiments on nightingales that examined whether such 'chunking' was susceptible to experimental cueing. The experiments tested whether (1) 'temporal phrasing' (silent intersong intervals spaced out at particular positions of a tutored string), or (2) 'stimulus novelty' (groups of novel song-types added to a basic string), or (3) 'pattern similarity' in the phonetic structure of songs (here: sharing of song initials) would induce package boundaries (or chunking) at the manipulated sequential positions. The results revealed cueing effects in experiments (1) and (2) but not in experiment (3). The finding that birds used temporal variables as cues for chunking does not require the assumption that package formation is a cognitive strategy. Rather, it points towards a mechanism of procedural memory operating in the song acquisition of birds.

  4. The Anterior Thalamus Provides A Subcortical Circuit Supporting Memory And Spatial Navigation

    Directory of Open Access Journals (Sweden)

    Shane M O‘Mara

    2013-08-01

    Full Text Available The anterior thalamic nuclei, a central component of Papez’ circuit, are generally assumed to be key constituents of the neural circuits responsible for certain categories of learning and memory. Supporting evidence for this contention is that damage to either of two brain regions, the medial temporal lobe and the medial diencephalon, is most consistently associated with anterograde amnesia. Within these respective regions, the hippocampal formation and the anterior thalamic nuclei (anteromedial, anteroventral, anterodorsal are the particular structures of interest. The extensive direct and indirect hippocampal-anterior thalamic interconnections and the presence of theta-modulated cells in both sites further support the hypothesis that these structures constitute a neuronal network crucial for memory and cognition. The major tool in understanding how the brain processes information is the analysis of neuronal output at each hierarchical level along the pathway of signal propagation coupled with neuroanatomical studies. Here, we discuss the electrophysiological properties of cells in the anterior thalamic nuclei with an emphasis on their role in spatial navigation. In addition, we describe neuroanatomical and functional relationships between the anterior thalamic nuclei and hippocampal formation.

  5. A Dynamical Model of Pitch Memory Provides an Improved Basis for Implied Harmony Estimation

    Science.gov (United States)

    Kim, Ji Chul

    2017-01-01

    Tonal melody can imply vertical harmony through a sequence of tones. Current methods for automatic chord estimation commonly use chroma-based features extracted from audio signals. However, the implied harmony of unaccompanied melodies can be difficult to estimate on the basis of chroma content in the presence of frequent nonchord tones. Here we present a novel approach to automatic chord estimation based on the human perception of pitch sequences. We use cohesion and inhibition between pitches in auditory short-term memory to differentiate chord tones and nonchord tones in tonal melodies. We model short-term pitch memory as a gradient frequency neural network, which is a biologically realistic model of auditory neural processing. The model is a dynamical system consisting of a network of tonotopically tuned nonlinear oscillators driven by audio signals. The oscillators interact with each other through nonlinear resonance and lateral inhibition, and the pattern of oscillatory traces emerging from the interactions is taken as a measure of pitch salience. We test the model with a collection of unaccompanied tonal melodies to evaluate it as a feature extractor for chord estimation. We show that chord tones are selectively enhanced in the response of the model, thereby increasing the accuracy of implied harmony estimation. We also find that, like other existing features for chord estimation, the performance of the model can be improved by using segmented input signals. We discuss possible ways to expand the present model into a full chord estimation system within the dynamical systems framework. PMID:28522983

  6. A Dynamical Model of Pitch Memory Provides an Improved Basis for Implied Harmony Estimation.

    Science.gov (United States)

    Kim, Ji Chul

    2017-01-01

    Tonal melody can imply vertical harmony through a sequence of tones. Current methods for automatic chord estimation commonly use chroma-based features extracted from audio signals. However, the implied harmony of unaccompanied melodies can be difficult to estimate on the basis of chroma content in the presence of frequent nonchord tones. Here we present a novel approach to automatic chord estimation based on the human perception of pitch sequences. We use cohesion and inhibition between pitches in auditory short-term memory to differentiate chord tones and nonchord tones in tonal melodies. We model short-term pitch memory as a gradient frequency neural network, which is a biologically realistic model of auditory neural processing. The model is a dynamical system consisting of a network of tonotopically tuned nonlinear oscillators driven by audio signals. The oscillators interact with each other through nonlinear resonance and lateral inhibition, and the pattern of oscillatory traces emerging from the interactions is taken as a measure of pitch salience. We test the model with a collection of unaccompanied tonal melodies to evaluate it as a feature extractor for chord estimation. We show that chord tones are selectively enhanced in the response of the model, thereby increasing the accuracy of implied harmony estimation. We also find that, like other existing features for chord estimation, the performance of the model can be improved by using segmented input signals. We discuss possible ways to expand the present model into a full chord estimation system within the dynamical systems framework.

  7. A Dynamical Model of Pitch Memory Provides an Improved Basis for Implied Harmony Estimation

    Directory of Open Access Journals (Sweden)

    Ji Chul Kim

    2017-05-01

    Full Text Available Tonal melody can imply vertical harmony through a sequence of tones. Current methods for automatic chord estimation commonly use chroma-based features extracted from audio signals. However, the implied harmony of unaccompanied melodies can be difficult to estimate on the basis of chroma content in the presence of frequent nonchord tones. Here we present a novel approach to automatic chord estimation based on the human perception of pitch sequences. We use cohesion and inhibition between pitches in auditory short-term memory to differentiate chord tones and nonchord tones in tonal melodies. We model short-term pitch memory as a gradient frequency neural network, which is a biologically realistic model of auditory neural processing. The model is a dynamical system consisting of a network of tonotopically tuned nonlinear oscillators driven by audio signals. The oscillators interact with each other through nonlinear resonance and lateral inhibition, and the pattern of oscillatory traces emerging from the interactions is taken as a measure of pitch salience. We test the model with a collection of unaccompanied tonal melodies to evaluate it as a feature extractor for chord estimation. We show that chord tones are selectively enhanced in the response of the model, thereby increasing the accuracy of implied harmony estimation. We also find that, like other existing features for chord estimation, the performance of the model can be improved by using segmented input signals. We discuss possible ways to expand the present model into a full chord estimation system within the dynamical systems framework.

  8. Finding the breech: Influence of breech presentation on mode of delivery based on timing of diagnosis, attempt at external cephalic version, and provider success with version.

    Science.gov (United States)

    Andrews, Suzanne; Leeman, Lawrence; Yonke, Nicole

    2017-09-01

    Breech presentation affects 3-4% of pregnancies at term and malpresentation is the primary indication for 10-15% of cesarean deliveries. External cephalic version is an effective intervention that can decrease the need for cesarean delivery; however, timely identification of breech presentation is required. We hypothesized that women with a fetus in a breech presentation that is diagnosed after 38 weeks' estimated gestational age have a decreased likelihood of external cephalic version attempted and an increased likelihood of cesarean delivery. This was a retrospective cohort study. A chart review was performed for 251 women with breech presentation at term presenting to our tertiary referral university hospital for external cephalic version, cesarean for breech presentation, or vaginal breech delivery. Vaginal delivery was significantly more likely (31.1% vs 12.5%; Pexternal cephalic version was offered, and subsequently attempted in a greater proportion of women diagnosed before 38 weeks. External cephalic version was more successful when performed by physicians with greater procedural volume during the 3.5 year period of the study (59.1% for providers performing at least 10 procedures vs 31.3% if performing fewer than 10 procedures, Pexternal cephalic version. © 2017 Wiley Periodicals, Inc.

  9. Return of spontaneous circulation and long-term survival according to feedback provided by automated external defibrillators

    DEFF Research Database (Denmark)

    Agerskov, M; Hansen, M B; Nielsen, A M

    2017-01-01

    levels. METHODS: We collected data on OHCA occurring between 2011 and 2014 in the Capital Region of Denmark where an AED was applied prior to ambulance arrival. Patient data were obtained from the Danish Cardiac Arrest Registry and medical records. AED data were retrieved from the Emergency Medical...... Dispatch Centre (EMDC) and information on feedback mechanisms, energy waveform and energy level was downloaded from the applied AEDs. RESULTS: A total of 196 OHCAs had an AED applied prior to ambulance arrival; 62 of these (32%) provided audio visual (AV) feedback while no feedback was provided in 134 (68...

  10. Memory

    OpenAIRE

    Wager, Nadia

    2017-01-01

    This chapter will explore a response to traumatic victimisation which has divided the opinions of psychologists at an exponential rate. We will be examining amnesia for memories of childhood sexual abuse and the potential to recover these memories in adulthood. Whilst this phenomenon is generally accepted in clinical circles, it is seen as highly contentious amongst research psychologists, particularly experimental cognitive psychologists. The chapter will begin with a real case study of a wo...

  11. Cognitive rehabilitation of episodic memory disorders: from theory to practice

    OpenAIRE

    Radek Ptak; Radek Ptak; Martial Van Der Linden; Armin Schnider; Armin Schnider

    2010-01-01

    Memory disorders are among the most frequent and most debilitating cognitive impairments following acquired brain damage. Cognitive remediation strategies attempt to restore lost memory capacity, provide compensatory techniques or teach the use of external memory aids. Memory rehabilitation has strongly been influenced by memory theory, and the interaction between both has stimulated the development of techniques such as spaced retrieval, vanishing cues or errorless learning. These techniques...

  12. Cognitive Rehabilitation of Episodic Memory Disorders: From Theory to Practice

    OpenAIRE

    Ptak, Radek; der Linden, Martial Van; Schnider, Armin

    2010-01-01

    Memory disorders are among the most frequent and most debilitating cognitive impairments following acquired brain damage. Cognitive remediation strategies attempt to restore lost memory capacity, provide compensatory techniques or teach the use of external memory aids. Memory rehabilitation has strongly been influenced by memory theory, and the interaction between both has stimulated the development of techniques such as spaced retrieval, vanishing cues or errorless learning. These techniques...

  13. AIRGAMMA, External Gamma-Ray Exposure from Radioactive Cloud

    International Nuclear Information System (INIS)

    Hidaka, Akihide; Iijima, Tshinori

    1989-01-01

    1 - Description of program or function: AIRGAMMA calculates quickly the external exposure to gamma rays from a radioactive cloud. 2 - Method of solution: The external exposure is calculated by interpolating the normalized doses providing on the basis of the Gaussian plume model. 3 - Restrictions on the complexity of the problem: Memory requirement is 30 Kbytes

  14. Maternal depression and trajectories of child internalizing and externalizing problems: the roles of child decision making and working memory

    OpenAIRE

    Flouri, E.; Ruddy, A.; Midouhas, E.

    2017-01-01

    BACKGROUND: Maternal depression may affect the emotional/behavioural outcomes of children with normal neurocognitive functioning less severely than it does those without. To guide prevention and intervention efforts, research must specify which aspects of a child's cognitive functioning both moderate the effect of maternal depression and are amenable to change. Working memory and decision making may be amenable to change and are so far unexplored as moderators of this effect. METHOD: Our samp...

  15. Memories.

    Science.gov (United States)

    Brand, Judith, Ed.

    1998-01-01

    This theme issue of the journal "Exploring" covers the topic of "memories" and describes an exhibition at San Francisco's Exploratorium that ran from May 22, 1998 through January 1999 and that contained over 40 hands-on exhibits, demonstrations, artworks, images, sounds, smells, and tastes that demonstrated and depicted the biological,…

  16. Skin effector memory T cells do not recirculate and provide immune protection in alemtuzumab-treated CTCL patients.

    Science.gov (United States)

    Clark, Rachael A; Watanabe, Rei; Teague, Jessica E; Schlapbach, Christoph; Tawa, Marianne C; Adams, Natalie; Dorosario, Andrew A; Chaney, Keri S; Cutler, Corey S; Leboeuf, Nicole R; Carter, Joi B; Fisher, David C; Kupper, Thomas S

    2012-01-18

    Cutaneous T cell lymphoma (CTCL) is a cancer of skin-homing T cells with variants that include leukemic CTCL (L-CTCL), a malignancy of central memory T cells (T(CM)), and mycosis fungoides (MF), a malignancy of skin resident effector memory T cells (T(EM)). We report that low-dose alemtuzumab (αCD52) effectively treated patients with refractory L-CTCL but not MF. Alemtuzumab depleted all T cells in blood and depleted both benign and malignant T(CM) from skin, but a diverse population of skin resident T(EM) remained in skin after therapy. T cell depletion with alemtuzumab required the presence of neutrophils, a cell type frequent in blood but rare in normal skin. These data suggest that T(CM) were depleted because they recirculate between the blood and the skin, whereas skin resident T(EM) were spared because they are sessile and non-recirculating. After alemtuzumab treatment, skin T cells produced lower amounts of interleukin-4 and higher amounts of interferon-γ. Moreover, there was a marked lack of infections in alemtuzumab-treated L-CTCL patients despite the complete absence of T cells in the blood, suggesting that skin resident T(EM) can protect the skin from pathogens even in the absence of T cell recruitment from the circulation. Together, these data suggest that alemtuzumab may treat refractory L-CTCL without severely compromising the immune response to infection by depleting circulating T(CM) but sparing the skin resident T(EM) that provide local immune protection of the skin.

  17. Social Intelligence and Top Management Team: An Exploratory Study of External Knowledge Acquisition for Strategic Change in Global IT Service Providers in India

    Science.gov (United States)

    Kong, Eric; Chadee, Doren; Raman, Revti

    2012-01-01

    This paper focuses on the processes by which firms, particularly knowledge intensive firms, can augment their overall knowledge stock by tapping into external sources of knowledge. It is argued that Top Management Teams' (TMTs') social intelligence is a critical learning capability in acquiring external knowledge that leads to strategic change.…

  18. Posttraining Increases in REM Sleep Intensity Implicate REM Sleep in Memory Processing and Provide a Biological Marker of Learning Potential

    Science.gov (United States)

    Nader, Rebecca S.; Smith, Carlyle T.; Nixon, Margaret R.

    2004-01-01

    Posttraining rapid eye movement (REM) sleep has been reported to be important for efficient memory consolidation. The present results demonstrate increases in the intensity of REM sleep during the night of sleep following cognitive procedural/implicit task acquisition. These REM increases manifest as increases in total number of rapid eye…

  19. Close but no cigar: Spatial precision deficits following medial temporal lobe lesions provide novel insight into theoretical models of navigation and memory.

    Science.gov (United States)

    Kolarik, Branden S; Baer, Trevor; Shahlaie, Kiarash; Yonelinas, Andrew P; Ekstrom, Arne D

    2018-01-01

    Increasing evidence suggests that the human hippocampus contributes to a range of different behaviors, including episodic memory, language, short-term memory, and navigation. A novel theoretical framework, the Precision and Binding Model, accounts for these phenomenon by describing a role for the hippocampus in high-resolution, complex binding. Other theories like Cognitive Map Theory, in contrast, predict a specific role for the hippocampus in allocentric navigation, while Declarative Memory Theory predicts a specific role in delay-dependent conscious memory. Navigation provides a unique venue for testing these predictions, with past results from research with humans providing inconsistent findings regarding the role of the human hippocampus in spatial navigation. Here, we tested five patients with lesions primarily restricted to the hippocampus and those extending out into the surrounding medial temporal lobe cortex on a virtual water maze task. Consistent with the Precision and Binding Model, we found partially intact allocentric memory in all patients, with impairments in the spatial precision of their searches for a hidden target. We found similar impairments at both immediate and delayed testing. Our findings are consistent with the Precision and Binding Model of hippocampal function, arguing for its role across domains in high-resolution, complex binding. Remembering goal locations in one's environment is a critical skill for survival. How this information is represented in the brain is still not fully understood, but is believed to rely in some capacity on structures in the medial temporal lobe. Contradictory findings from studies of both humans and animals have been difficult to reconcile with regard to the role of the MTL, specifically the hippocampus. By assessing impairments observed during navigation to a goal in patients with medial temporal lobe damage we can better understand the role these structures play in such behavior. Utilizing virtual reality

  20. Comparative kinetics of damage to the plasma and mitochondrial membranes by intra-cellularly synthesized and externally-provided photosensitizers using multi-color FACS.

    Science.gov (United States)

    Haupt, Sara; Malik, Zvi; Ehrenberg, Benjamin

    2014-01-01

    Photodynamic therapy (PDT) of cancer involves inflicting lethal damage to the cells of malignant tumors, primarily by singlet oxygen that is generated following light-absorption in a photosensitizer molecule. Dysfunction of cells is manifested in many ways, including peroxidation of cellular components, membrane rupture, depolarization of electric potentials, termination of mitochondrial activity, onset of apoptosis and necrosis and eventually cell lysis. These events do not necessarily occur in linear fashion and different types of damage to cell components occur, most probably, in parallel. In this report we measured the relative rates of damage to two cellular membranes: the plasma membrane and the mitochondrial membrane. We employed photosensitizers of diverse hydrophobicities and used different incubation procedures, which lead to their different intra-cellular localizations. We monitored the damage that was inflicted on these membranes, by employing optical probes of membrane integrity, in a multi-color FACS experiment. The potentiometric indicator JC-1 monitored the electric cross-membrane potential of the mitochondria and the fluorometric indicator Draq7 monitored the rupture of the plasma membrane. We show that the electric depolarization of the mitochondrial membrane and the damage to the enveloping plasma membrane proceed with different kinetics that reflect the molecular character and intracellular location of the sensitizer: PpIX that is synthesized in the cells from ALA causes rapid mitochondrial damage and very slow damage to the plasma membrane, while externally added PpIX has an opposite effect. The hydrophilic sensitizer HypS4 can be taken up by the cells by different incubation conditions, and these affect its intracellular location, and as a consequence either the plasma membrane or the mitochondria is damaged first. A similar correlation was found for additional extracellularly-provided photosensitizers HP and PpIX.

  1. Providers with Limited Experience Perform Better in Advanced Life Support with Assistance Using an Interactive Device with an Automated External Defibrillator Linked to a Ventilator.

    Science.gov (United States)

    Busch, Christian Werner; Qalanawi, Mohammed; Kersten, Jan Felix; Kalwa, Tobias Johannes; Scotti, Norman Alexander; Reip, Wikhart; Doehn, Christoph; Maisch, Stefan; Nitzschke, Rainer

    2015-10-01

    Medical teams with limited experience in performing advanced life support (ALS) or with a low frequency of cardiopulmonary resuscitation (CPR) while on duty, often have difficulty complying with CPR guidelines. This study evaluated whether the quality of CPR of trained medical students, who served as an example of teams with limited experience in ALS, could be improved with device assistance. The primary outcome was the hands-off time (i.e., the percentage of the entire CPR time without chest compressions). The secondary outcome was seven time intervals, which should be as short as possible, and the quality of ventilations and chest compressions on the mannequin. We compared standard CPR equipment to an interactive device with visual and acoustic instructions for ALS workflow measures to guide briefly trained medical students through the ALS algorithm in a full-scale mannequin simulation study with a randomized crossover study design. The study equipment consisted of an automatic external defibrillator and ventilator that were electronically linked and communicating as a single system. Included were regular medical students in the third to sixth years of medical school of one class who provided written informed consent for voluntary participation and for the analysis of their CPR performance data. No exclusion criteria were applied. For statistical measures of evaluation we used an analysis of variance for crossover trials accounting for treatment effect, sequence effect, and carry-over effect, with adjustment for prior practical experience of the participants. Forty-two medical students participated in 21 CPR sessions, each using the standard and study equipment. Regarding the primary end point, the study equipment reduced the hands-off time from 40.1% (95% confidence interval [CI] 36.9-43.4%) to 35.6% (95% CI 32.4-38.9%, p = 0.031) compared with the standard equipment. Within the prespecified secondary end points, study equipment reduced the time interval until

  2. Regional Externalities

    NARCIS (Netherlands)

    Heijman, W.J.M.

    2007-01-01

    The book offers practical and theoretical insights in regional externalities. Regional externalities are a specific subset of externalities that can be defined as externalities where space plays a dominant role. This class of externalities can be divided into three categories: (1) externalities

  3. Facilitators and barriers to external cephalic version for breech presentation at term among health care providers in the Netherlands: a quantitative analysis

    NARCIS (Netherlands)

    Rosman, Ageeth N.; Vlemmix, Floortje; Beuckens, Antje; Rijnders, Marlies E.; Opmeer, Brent C.; Mol, Ben Willem J.; Kok, Marjolein; Fleuren, Margot A. H.

    2014-01-01

    guidelines recommend that external cephalic version (ECV) should be offered to all women with a fetus in breech presentation at term. However, only 50-60% of the women receive an ECV attempt. We explored the determinants (barriers and facilitators) affecting the uptake of the guidelines among

  4. Facilitators and barriers to external cephalic version for breech presentation at term among health care providers in the Netherlands: A quantitative analysis

    NARCIS (Netherlands)

    Rosman, A.N.; Vlemmix, F.; Beuckens, A.; Rijnders, M.E.; Opmeer, B.C.; Mol, B.W.J.; Kok, M.; Fleuren, M.A.H.

    2014-01-01

    OBJECTIVE: guidelines recommend that external cephalic version (ECV) should be offered to all women with a fetus in breech presentation at term. However, only 50-60% of the women receive an ECV attempt. We explored the determinants (barriers and facilitators) affecting the uptake of the guidelines

  5. Accessing memory

    Science.gov (United States)

    Yoon, Doe Hyun; Muralimanohar, Naveen; Chang, Jichuan; Ranganthan, Parthasarathy

    2017-09-26

    A disclosed example method involves performing simultaneous data accesses on at least first and second independently selectable logical sub-ranks to access first data via a wide internal data bus in a memory device. The memory device includes a translation buffer chip, memory chips in independently selectable logical sub-ranks, a narrow external data bus to connect the translation buffer chip to a memory controller, and the wide internal data bus between the translation buffer chip and the memory chips. A data access is performed on only the first independently selectable logical sub-rank to access second data via the wide internal data bus. The example method also involves locating a first portion of the first data, a second portion of the first data, and the second data on the narrow external data bus during separate data transfers.

  6. External and Internal Citation Analyses Can Provide Insight into Serial/Monograph Ratios when Refining Collection Development Strategies in Selected STEM Disciplines

    Directory of Open Access Journals (Sweden)

    Stephanie Krueger

    2016-12-01

    Full Text Available A Review of: Kelly, M. (2015. Citation patterns of engineering, statistics, and computer science researchers: An internal and external citation analysis across multiple engineering subfields. College and Research Libraries, 76(7, 859-882. http://doi.org/10.5860/crl.76.7.859 Objective – To determine internal and external citation analysis methods and their potential applicability to the refinement of collection development strategies at both the institutional and cross-institutional levels for selected science, technology, engineering, and mathematics (STEM subfields. Design – Multidimensional citation analysis; specifically, analysis of citations from 1 key scholarly journals in selected STEM subfields (external analysis compared to those from 2 local doctoral dissertations in similar subfields (internal analysis. Setting – Medium-sized, STEM-dominant public research university in the United States of America. Subjects – Two citation datasets: 1 14,149 external citations from16 journals (i.e., 2 journals per subfield; citations from 2012 volumes representing bioengineering, civil engineering, computer science (CS, electrical engineering, environmental engineering, operations research, statistics (STAT, and systems engineering; and 2 8,494 internal citations from 99 doctoral dissertations (18-22 per subfield published between 2008-–2012 from CS, electrical and computer engineering (ECE, and applied information technology (AIT and published between 2005-–2012 for systems engineering and operations research (SEOR and STAT. Methods – Citations, including titles and publication dates, were harvested from source materials and stored in Excel and then manually categorized according to format (book, book chapter, journal, conference proceeding, website, and several others. To analyze citations, percentages of occurrence by subfield were calculated for variables including format, age (years since date cited, journal distribution, and the

  7. Memory-Focused Cognitive Therapy for Cocaine Use Disorder: Theory, Procedures and Preliminary Evidence From an External Pilot Randomised Controlled Trial

    Directory of Open Access Journals (Sweden)

    John Marsden

    2018-03-01

    Full Text Available Background: Cocaine use disorder (CUD is a debilitating condition with no NICE-recommended medication or specific psychosocial interventions. In the United Kingdom (UK, general counselling (treatment-as-usual; TAU is widely delivered, but has limited effectiveness. We tested the feasibility, safety and preliminary efficacy of a novel, adjunctive psychosocial intervention for CUD, called ‘memory-focused cognitive therapy’ (MFCT. Methods: We did a two-arm, external pilot randomised controlled trial at a specialist community National Health Service addictions clinic in London, UK. 30 adults (≥18 years, voluntarily seeking treatment for CUD (enrolled ≥14 days; all with moderate-to-severe DSM5 CUD, were individually randomised (1:1 to a control group (ongoing TAU; 3 × 90 min CUD cognitive conceptualisation assessments; 2 × 30 min cocaine-related cue-induction procedures; and 3 × 30 min research follow-ups; or to an intervention group (ongoing TAU; 3 × 90 min cognitive conceptualisation assessments; 2 × 30 min cocaine-related cue-induction procedures; 5 × 120 min, one-to-one, MFCT sessions [in 1 week]; and 3 × 60 min research follow-ups and MFCT-relapse prevention.The primary outcome was the total percentage score on the frequency version of the Craving Experiences Questionnaire (CEQ-F at 1-month follow-up after the intensive intervention week (clinical endpoint; recall period past 2 weeks; higher score indicating greater craving. Secondary outcomes at the 1-month follow-up were percentage days abstinent (PDA from cocaine, and longest period (days of continuous abstinence (LPA in the prior 28 days.Outcomes were analysed as an unadjusted group mean difference (with Hedge's g effect size [ES] and a 95% Confidence Interval [CI] for the primary outcome and a 90% CI for the secondary outcomes. Exploratory, multivariable linear (primary outcome and Poisson regression models (secondary outcomes, with sex, age, months

  8. Investigation of fast initialization of spacecraft bubble memory systems

    Science.gov (United States)

    Looney, K. T.; Nichols, C. D.; Hayes, P. J.

    1984-01-01

    Bubble domain technology offers significant improvement in reliability and functionality for spacecraft onboard memory applications. In considering potential memory systems organizations, minimization of power in high capacity bubble memory systems necessitates the activation of only the desired portions of the memory. In power strobing arbitrary memory segments, a capability of fast turn on is required. Bubble device architectures, which provide redundant loop coding in the bubble devices, limit the initialization speed. Alternate initialization techniques are investigated to overcome this design limitation. An initialization technique using a small amount of external storage is demonstrated.

  9. Quantum memory Quantum memory

    Science.gov (United States)

    Le Gouët, Jean-Louis; Moiseev, Sergey

    2012-06-01

    Interaction of quantum radiation with multi-particle ensembles has sparked off intense research efforts during the past decade. Emblematic of this field is the quantum memory scheme, where a quantum state of light is mapped onto an ensemble of atoms and then recovered in its original shape. While opening new access to the basics of light-atom interaction, quantum memory also appears as a key element for information processing applications, such as linear optics quantum computation and long-distance quantum communication via quantum repeaters. Not surprisingly, it is far from trivial to practically recover a stored quantum state of light and, although impressive progress has already been accomplished, researchers are still struggling to reach this ambitious objective. This special issue provides an account of the state-of-the-art in a fast-moving research area that makes physicists, engineers and chemists work together at the forefront of their discipline, involving quantum fields and atoms in different media, magnetic resonance techniques and material science. Various strategies have been considered to store and retrieve quantum light. The explored designs belong to three main—while still overlapping—classes. In architectures derived from photon echo, information is mapped over the spectral components of inhomogeneously broadened absorption bands, such as those encountered in rare earth ion doped crystals and atomic gases in external gradient magnetic field. Protocols based on electromagnetic induced transparency also rely on resonant excitation and are ideally suited to the homogeneous absorption lines offered by laser cooled atomic clouds or ion Coulomb crystals. Finally off-resonance approaches are illustrated by Faraday and Raman processes. Coupling with an optical cavity may enhance the storage process, even for negligibly small atom number. Multiple scattering is also proposed as a way to enlarge the quantum interaction distance of light with matter. The

  10. Facilitators and barriers to external cephalic version for breech presentation at term among health care providers in the Netherlands: a quantitative analysis.

    Science.gov (United States)

    Rosman, Ageeth N; Vlemmix, Floortje; Beuckens, Antje; Rijnders, Marlies E; Opmeer, Brent C; Mol, Ben Willem J; Kok, Marjolein; Fleuren, Margot A H

    2014-03-01

    guidelines recommend that external cephalic version (ECV) should be offered to all women with a fetus in breech presentation at term. However, only 50-60% of the women receive an ECV attempt. We explored the determinants (barriers and facilitators) affecting the uptake of the guidelines among gynaecologists and midwives in the Netherlands. national online survey. the Netherlands. gynaecologists and midwives. in the online survey, we identified the determinants that positively or negatively influenced the professionals׳ adherence to three key recommendations in the guidelines: (a) counselling, (b) advising for ECV, (c) arranging an ECV. Determinants were identified in a previously performed qualitative study and were categorised into five underlying constructs; attitude towards ECV, professional obligation, outcome expectations, self-efficacy and preconditions for successful ECV. We performed a multivariate analysis to assess the importance of the different constructs for adherence to the guideline. 364 professionals responded to the survey. Adherence varied: 84% counselled, 73% advised, and 82% arranged an ECV for (almost) all their clients. Although 90% of respondents considered ECV to be an effective treatment for preventing caesarean childbirths, only 30% agreed that 'every client should undergo ECV'. Self-efficacy (perceived skills) was the most important determinant influencing adherence. self-efficacy appears to be the most significant determinant for counselling, advising and arranging an ECV. to improve adherence to the guidelines on ECV we must improve self-efficacy. Copyright © 2014. Published by Elsevier Ltd.

  11. Observation of martensitic structure evolution in Cu-Al-Ni single crystals with shape memory effect under external load using photoacoustic microscopy

    International Nuclear Information System (INIS)

    Muratikov, K.L.; Glazov, A.L.; Nikolaev, V.I.; Pul'nev, S.A.

    2006-01-01

    Photoacoustic microscopy is applied to observe the surface structure of Cu-Al-Ni shape-memory single crystals in both the loaded and unloaded states. Visualizing the early stages of the loading-induced martensitic transformation in Cu-Al-Ni single crystals is demonstrated to be feasible. The photoacoustic images are distinguished to advantage from the corresponding optical images by a higher contrast between different phases of the Cu-Al-Ni shape-memory alloy [ru

  12. ASH External Web Portal (External Portal) -

    Data.gov (United States)

    Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

  13. PKA Increases in the Olfactory Bulb Act as Unconditioned Stimuli and Provide Evidence for Parallel Memory Systems: Pairing Odor with Increased PKA Creates Intermediate- and Long-Term, but Not Short-Term, Memories

    Science.gov (United States)

    Grimes, Matthew T.; Harley, Carolyn W.; Darby-King, Andrea; McLean, John H.

    2012-01-01

    Neonatal odor-preference memory in rat pups is a well-defined associative mammalian memory model dependent on cAMP. Previous work from this laboratory demonstrates three phases of neonatal odor-preference memory: short-term (translation-independent), intermediate-term (translation-dependent), and long-term (transcription- and…

  14. Estimating location without external cues.

    Directory of Open Access Journals (Sweden)

    Allen Cheung

    2014-10-01

    Full Text Available The ability to determine one's location is fundamental to spatial navigation. Here, it is shown that localization is theoretically possible without the use of external cues, and without knowledge of initial position or orientation. With only error-prone self-motion estimates as input, a fully disoriented agent can, in principle, determine its location in familiar spaces with 1-fold rotational symmetry. Surprisingly, localization does not require the sensing of any external cue, including the boundary. The combination of self-motion estimates and an internal map of the arena provide enough information for localization. This stands in conflict with the supposition that 2D arenas are analogous to open fields. Using a rodent error model, it is shown that the localization performance which can be achieved is enough to initiate and maintain stable firing patterns like those of grid cells, starting from full disorientation. Successful localization was achieved when the rotational asymmetry was due to the external boundary, an interior barrier or a void space within an arena. Optimal localization performance was found to depend on arena shape, arena size, local and global rotational asymmetry, and the structure of the path taken during localization. Since allothetic cues including visual and boundary contact cues were not present, localization necessarily relied on the fusion of idiothetic self-motion cues and memory of the boundary. Implications for spatial navigation mechanisms are discussed, including possible relationships with place field overdispersion and hippocampal reverse replay. Based on these results, experiments are suggested to identify if and where information fusion occurs in the mammalian spatial memory system.

  15. PKA increases in the olfactory bulb act as unconditioned stimuli and provide evidence for parallel memory systems: pairing odor with increased PKA creates intermediate- and long-term, but not short-term, memories.

    Science.gov (United States)

    Grimes, Matthew T; Harley, Carolyn W; Darby-King, Andrea; McLean, John H

    2012-02-21

    Neonatal odor-preference memory in rat pups is a well-defined associative mammalian memory model dependent on cAMP. Previous work from this laboratory demonstrates three phases of neonatal odor-preference memory: short-term (translation-independent), intermediate-term (translation-dependent), and long-term (transcription- and translation-dependent). Here, we use neonatal odor-preference learning to explore the role of olfactory bulb PKA in these three phases of mammalian memory. PKA activity increased normally in learning animals 10 min after a single training trial. Inhibition of PKA by Rp-cAMPs blocked intermediate-term and long-term memory, with no effect on short-term memory. PKA inhibition also prevented learning-associated CREB phosphorylation, a transcription factor implicated in long-term memory. When long-term memory was rescued through increased β-adrenoceptor activation, CREB phosphorylation was restored. Intermediate-term and long-term, but not short-term odor-preference memories were generated by pairing odor with direct PKA activation using intrabulbar Sp-cAMPs, which bypasses β-adrenoceptor activation. Higher levels of Sp-cAMPs enhanced memory by extending normal 24-h retention to 48-72 h. These results suggest that increased bulbar PKA is necessary and sufficient for the induction of intermediate-term and long-term odor-preference memory, and suggest that PKA activation levels also modulate memory duration. However, short-term memory appears to use molecular mechanisms other than the PKA/CREB pathway. These mechanisms, which are also recruited by β-adrenoceptor activation, must operate in parallel with PKA activation.

  16. A nanowire magnetic memory cell based on a periodic magnetic superlattice

    International Nuclear Information System (INIS)

    Song, J-F; Bird, J P; Ochiai, Y

    2005-01-01

    We analyse the operation of a semiconductor nanowire-based memory cell. Large changes in the nanowire conductance result when the magnetization of a periodic array of nanoscale magnetic gates, which comprise the other key component of the memory cell, is switched between distinct configurations by an external magnetic field. The resulting conductance change provides the basis for a robust memory effect, which can be implemented in a semiconductor structure compatible with conventional semiconductor integrated circuits

  17. Episodic Memories

    Science.gov (United States)

    Conway, Martin A.

    2009-01-01

    An account of episodic memories is developed that focuses on the types of knowledge they represent, their properties, and the functions they might serve. It is proposed that episodic memories consist of "episodic elements," summary records of experience often in the form of visual images, associated to a "conceptual frame" that provides a…

  18. ExternE: Externalities of energy Vol. 2. Methodology

    International Nuclear Information System (INIS)

    Berry, J.; Holland, M.; Watkiss, P.

    1995-01-01

    This report describes the methodology used by the ExternE Project of the European Commission (DGXII) JOULE Programme for assessment of the external costs of energy. It is one of a series of reports describing analysis of nuclear, fossil and renewable fuel cycles for assessment of the externalities associated with electricity generation. Part I of the report deals with analysis of impacts, and Part II with the economic valuation of those impacts. Analysis is conducted on a marginal basis, to allow the effect of an incremental investment in a given technology to be quantified. Attention has been paid to the specificity of results with respect to the location of fuel cycle activities, the precise technologies used, and the type and source of fuel. The main advantages of this detailed approach are as follows: It takes full and proper account of the variability of impacts that might result from different power projects; It is more transparent than analysis based on hypothetically 'representative' cases for each of the different fuel cycles; It provides a framework for consistent comparison between fuel cycles. A wide variety of impacts have been considered. These include the effects of air pollution on the natural and human environment, consequences of accidents in the workplace, impacts of noise and visual intrusion on amenity, and the effects of climate change arising from the release of greenhouse gases. Wherever possible we have used the 'impact pathway' or 'damage function' approach to follow the analysis from identification of burdens (e.g. emissions) through to impact assessment and then valuation in monetary terms. This has required a detailed knowledge of the technologies involved, pollutant dispersion, analysis of effects on human and environmental health, and economics. In view of this the project brought together a multi-disciplinary team with experts from many European countries and the USA. The spatial and temporal ranges considered in the analysis are

  19. Semantic graphs and associative memories

    Science.gov (United States)

    Pomi, Andrés; Mizraji, Eduardo

    2004-12-01

    Graphs have been increasingly utilized in the characterization of complex networks from diverse origins, including different kinds of semantic networks. Human memories are associative and are known to support complex semantic nets; these nets are represented by graphs. However, it is not known how the brain can sustain these semantic graphs. The vision of cognitive brain activities, shown by modern functional imaging techniques, assigns renewed value to classical distributed associative memory models. Here we show that these neural network models, also known as correlation matrix memories, naturally support a graph representation of the stored semantic structure. We demonstrate that the adjacency matrix of this graph of associations is just the memory coded with the standard basis of the concept vector space, and that the spectrum of the graph is a code invariant of the memory. As long as the assumptions of the model remain valid this result provides a practical method to predict and modify the evolution of the cognitive dynamics. Also, it could provide us with a way to comprehend how individual brains that map the external reality, almost surely with different particular vector representations, are nevertheless able to communicate and share a common knowledge of the world. We finish presenting adaptive association graphs, an extension of the model that makes use of the tensor product, which provides a solution to the known problem of branching in semantic nets.

  20. A Memory Hierarchy Model Based on Data Reuse for Full-Search Motion Estimation on High-Definition Digital Videos

    Directory of Open Access Journals (Sweden)

    Alba Sandyra Bezerra Lopes

    2012-01-01

    Full Text Available The motion estimation is the most complex module in a video encoder requiring a high processing throughput and high memory bandwidth, mainly when the focus is high-definition videos. The throughput problem can be solved increasing the parallelism in the internal operations. The external memory bandwidth may be reduced using a memory hierarchy. This work presents a memory hierarchy model for a full-search motion estimation core. The proposed memory hierarchy model is based on a data reuse scheme considering the full search algorithm features. The proposed memory hierarchy expressively reduces the external memory bandwidth required for the motion estimation process, and it provides a very high data throughput for the ME core. This throughput is necessary to achieve real time when processing high-definition videos. When considering the worst bandwidth scenario, this memory hierarchy is able to reduce the external memory bandwidth in 578 times. A case study for the proposed hierarchy, using 32×32 search window and 8×8 block size, was implemented and prototyped on a Virtex 4 FPGA. The results show that it is possible to reach 38 frames per second when processing full HD frames (1920×1080 pixels using nearly 299 Mbytes per second of external memory bandwidth.

  1. Cognitive rehabilitation of episodic memory disorders: from theory to practice

    Directory of Open Access Journals (Sweden)

    Radek Ptak

    2010-07-01

    Full Text Available Memory disorders are among the most frequent and most debilitating cognitive impairments following acquired brain damage. Cognitive remediation strategies attempt to restore lost memory capacity, provide compensatory techniques or teach the use of external memory aids. Memory rehabilitation has strongly been influenced by memory theory, and the interaction between both has stimulated the development of techniques such as spaced retrieval, vanishing cues or errorless learning. These techniques partly rely on implicit memory and therefore enable even patients with dense amnesia to acquire new information. However, knowledge acquired in this way is often strongly domain-specific and inflexible. In addition, individual patients with amnesia respond differently to distinct interventions. The factors underlying these differences have not yet been identified. Behavioural management of memory failures therefore often relies on a careful description of environmental factors and measurement of associated behavioural disorders such as unawareness of memory failures. The current evidence suggests that patients with less severe disorders benefit from self-management techniques and mnemonics whereas rehabilitation of severely amnesic patients should focus on behaviour management, the transmission of domain-specific knowledge through implicit memory processes and the compensation for memory deficits with memory aids.

  2. CD27 instructs CD4+ T cells to provide help for the memory CD8+ T cell response after protein immunization

    NARCIS (Netherlands)

    Xiao, Yanling; Peperzak, Victor; Keller, Anna M.; Borst, Jannie

    2008-01-01

    For optimal quality, memory CD8(+) T cells require CD4(+) T cell help. We have examined whether CD4(+) T cells require CD27 to deliver this help, in a model of intranasal OVA protein immunization. CD27 deficiency reduced the capacity of CD4(+) T cells to support Ag-specific CD8(+) T cell

  3. Kinetic memory based on the enzyme-limited competition.

    Science.gov (United States)

    Hatakeyama, Tetsuhiro S; Kaneko, Kunihiko

    2014-08-01

    Cellular memory, which allows cells to retain information from their environment, is important for a variety of cellular functions, such as adaptation to external stimuli, cell differentiation, and synaptic plasticity. Although posttranslational modifications have received much attention as a source of cellular memory, the mechanisms directing such alterations have not been fully uncovered. It may be possible to embed memory in multiple stable states in dynamical systems governing modifications. However, several experiments on modifications of proteins suggest long-term relaxation depending on experienced external conditions, without explicit switches over multi-stable states. As an alternative to a multistability memory scheme, we propose "kinetic memory" for epigenetic cellular memory, in which memory is stored as a slow-relaxation process far from a stable fixed state. Information from previous environmental exposure is retained as the long-term maintenance of a cellular state, rather than switches over fixed states. To demonstrate this kinetic memory, we study several models in which multimeric proteins undergo catalytic modifications (e.g., phosphorylation and methylation), and find that a slow relaxation process of the modification state, logarithmic in time, appears when the concentration of a catalyst (enzyme) involved in the modification reactions is lower than that of the substrates. Sharp transitions from a normal fast-relaxation phase into this slow-relaxation phase are revealed, and explained by enzyme-limited competition among modification reactions. The slow-relaxation process is confirmed by simulations of several models of catalytic reactions of protein modifications, and it enables the memorization of external stimuli, as its time course depends crucially on the history of the stimuli. This kinetic memory provides novel insight into a broad class of cellular memory and functions. In particular, applications for long-term potentiation are discussed

  4. Olfactory Memory

    Science.gov (United States)

    Eichenbaum, Howard; Robitsek, R. Jonathan

    2009-01-01

    Odor-recognition memory in rodents may provide a valuable model of cognitive aging. In a recent study we used signal detection analyses to distinguish odor recognition based on recollection versus that based on familiarity. Aged rats were selectively impaired in recollection, with relative sparing of familiarity, and the deficits in recollection were correlated with spatial memory impairments. These results complement electro-physiological findings indicating age-associated deficits in the ability of hippocampal neurons to differentiate contextual information, and this information-processing impairment may underlie the common age-associated decline in olfactory and spatial memory. PMID:19686208

  5. Memory: sins and virtues

    OpenAIRE

    Schacter, Daniel L.

    2013-01-01

    Memory plays an important role in everyday life but does not provide an exact and unchanging record of experience: research has documented that memory is a constructive process that is subject to a variety of errors and distortions. Yet these memory “sins” also reflect the operation of adaptive aspects of memory. Memory can thus be characterized as an adaptive constructive process, which plays a functional role in cognition but produces distortions, errors, or illusions as a consequence of d...

  6. Nanoscale memory devices

    International Nuclear Information System (INIS)

    Chung, Andy; Deen, Jamal; Lee, Jeong-Soo; Meyyappan, M

    2010-01-01

    This article reviews the current status and future prospects for the use of nanomaterials and devices in memory technology. First, the status and continuing scaling trends of the flash memory are discussed. Then, a detailed discussion on technologies trying to replace flash in the near-term is provided. This includes phase change random access memory, Fe random access memory and magnetic random access memory. The long-term nanotechnology prospects for memory devices include carbon-nanotube-based memory, molecular electronics and memristors based on resistive materials such as TiO 2 . (topical review)

  7. Attending to auditory memory.

    Science.gov (United States)

    Zimmermann, Jacqueline F; Moscovitch, Morris; Alain, Claude

    2016-06-01

    Attention to memory describes the process of attending to memory traces when the object is no longer present. It has been studied primarily for representations of visual stimuli with only few studies examining attention to sound object representations in short-term memory. Here, we review the interplay of attention and auditory memory with an emphasis on 1) attending to auditory memory in the absence of related external stimuli (i.e., reflective attention) and 2) effects of existing memory on guiding attention. Attention to auditory memory is discussed in the context of change deafness, and we argue that failures to detect changes in our auditory environments are most likely the result of a faulty comparison system of incoming and stored information. Also, objects are the primary building blocks of auditory attention, but attention can also be directed to individual features (e.g., pitch). We review short-term and long-term memory guided modulation of attention based on characteristic features, location, and/or semantic properties of auditory objects, and propose that auditory attention to memory pathways emerge after sensory memory. A neural model for auditory attention to memory is developed, which comprises two separate pathways in the parietal cortex, one involved in attention to higher-order features and the other involved in attention to sensory information. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Dexras1 a unique ras-GTPase interacts with NMDA receptor activity and provides a novel dissociation between anxiety, working memory and sensory gating.

    Science.gov (United States)

    Carlson, G C; Lin, R E; Chen, Y; Brookshire, B R; White, R S; Lucki, I; Siegel, S J; Kim, S F

    2016-05-13

    Dexras1 is a novel GTPase that acts at a confluence of signaling mechanisms associated with psychiatric and neurological disease including NMDA receptors, NOS1AP and nNOS. Recent work has shown that Dexras1 mediates iron trafficking and NMDA-dependent neurodegeneration but a role for Dexras1 in normal brain function or psychiatric disease has not been studied. To test for such a role, mice with germline knockout (KO) of Dexras1 were assayed for behavioral abnormalities as well as changes in NMDA receptor subunit protein expression. Because Dexras1 is up-regulated during stress or by dexamethasone treatment, we included measures associated with emotion including anxiety and depression. Baseline anxiety-like measures (open field and zero maze) were not altered, nor were depression-like behavior (tail suspension). Measures of memory function yielded mixed results, with no changes in episodic memory (novel object recognition) but a significant decrement on working memory (T-maze). Alternatively, there was an increase in pre-pulse inhibition (PPI), without concomitant changes in either startle amplitude or locomotor activity. PPI data are consistent with the direction of change seen following exposure to dopamine D2 antagonists. An examination of NMDA subunit expression levels revealed an increased expression of the NR2A subunit, contrary to previous studies demonstrating down-regulation of the receptor following antipsychotic exposure (Schmitt et al., 2003) and up-regulation after exposure to isolation rearing (Turnock-Jones et al., 2009). These findings suggest a potential role for Dexras1 in modulating a selective subset of psychiatric symptoms, possibly via its interaction with NMDARs and/or other disease-related binding-partners. Furthermore, data suggest that modulating Dexras1 activity has contrasting effects on emotional, sensory and cognitive domains. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Caspase-9 mediates synaptic plasticity and memory deficits of Danish dementia knock-in mice: caspase-9 inhibition provides therapeutic protection

    Directory of Open Access Journals (Sweden)

    Tamayev Robert

    2012-12-01

    Full Text Available Abstract Background Mutations in either Aβ Precursor protein (APP or genes that regulate APP processing, such as BRI2/ITM2B and PSEN1/PSEN2, cause familial dementias. Although dementias due to APP/PSEN1/PSEN2 mutations are classified as familial Alzheimer disease (FAD and those due to mutations in BRI2/ITM2B as British and Danish dementias (FBD, FDD, data suggest that these diseases have a common pathogenesis involving toxic APP metabolites. It was previously shown that FAD mutations in APP and PSENs promote activation of caspases leading to the hypothesis that aberrant caspase activation could participate in AD pathogenesis. Results Here, we tested whether a similar mechanism applies to the Danish BRI2/ITM2B mutation. We have generated a genetically congruous mouse model of FDD, called FDDKI, which presents memory and synaptic plasticity deficits. We found that caspase-9 is activated in hippocampal synaptic fractions of FDDKI mice and inhibition of caspase-9 activity rescues both synaptic plasticity and memory deficits. Conclusion These data directly implicate caspase-9 in the pathogenesis of Danish dementia and suggest that reducing caspase-9 activity is a valid therapeutic approach to treating human dementias.

  10. Stochastic memory: Memory enhancement due to noise

    Science.gov (United States)

    Stotland, Alexander; di Ventra, Massimiliano

    2012-01-01

    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO2 thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  11. Computing visibility on terrains in external memory

    NARCIS (Netherlands)

    Haverkort, H.J.; Toma, L.; Zhuang, Yi

    2007-01-01

    We describe a novel application of the distribution sweeping technique to computing visibility on terrains. Given an arbitrary viewpoint v, the basic problem we address is computing the visibility map or viewshed of v, which is the set of points in the terrain that are visible from v. We give the

  12. ExternE: Externalities of energy Vol. 1. Summary

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1995-01-01

    energy use in the transport and domestic sectors and a number of non-environmental externalities. Phase 3 of the project will be undertaken within the European Commission's 4th Framework Programme (1995-1998) and will concentrate on the application of the accounting framework in support of policy issues and decision making. A major result of this work is the methodology which has been developed. This is a significant advance on earlier studies of the external costs of energy. It provides a transparent basis on which different impacts, technologies and locations may be compared. It is suitable for evaluation of the health and environmental damages due to increments in electricity production, with or without monetary valuation of the impacts. This report reviews this methodology and presents the major results obtained in its application to seven important fuel cycles, namely the coal, lignite, oil, gas, nuclear, hydro and wind fuel cycles. Chapter 2 reviews the methodology developed for the quantification of impacts and discusses the associated issues. Chapter 3 discusses the methodological issues associated with the economic valuation of impacts. Chapters 4 and 5 report in detail on the assessment of the coal and nuclear fuel cycles. Chapter 6 summarises the progress that has been made to date on the ExternE Project and presents a comparison of the results obtained for the four fossil fuel cycles together with results from the nuclear and renewable fuel cycles. This project is at the forefront of work in this area. It has drawn together an extensive multidisciplinary team of environmental scientists, energy technologists, health and ecology experts, atmospheric modellers, economists and computer analysts. The results obtained are based on thorough review of scientific and economic studies. This does not mean that exact values have been established for external costs. Indeed, one of our most important conclusions is that the uncertainties are large. Previous analyses

  13. Externalities of fuel cycles 'ExternE' project. Summary report

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1994-01-01

    energy use in the transport and domestic sectors and a number of non-environmental externalities. Phase 3 of the project will be undertaken within the European Commission's 4th Framework Programme (1995-1998) and will concentrate on the application of the accounting framework in support of policy issues and decision making. A major result of this work is the methodology which has been developed. This is a significant advance on earlier studies of the external costs of energy. It provides a transparent basis on which different impacts, technologies and locations may be compared. It is suitable for evaluation of the health and environmental damages due to increments in electricity production, with or without monetary valuation of the impacts. This report reviews this methodology and presents the major results obtained in its application to seven important fuel cycles, namely the coal, lignite, oil, gas, nuclear, hydro and wind fuel cycles. Chapter 2 reviews the methodology developed for the quantification of impacts and discusses the associated issues. Chapter 3 discusses the methodological issues associated with the economic valuation of impacts. Chapters 4 and 5 report in detail on the assessment of the coal and nuclear fuel cycles. Chapter 6 summarises the progress that has been made to date on the ExternE Project and presents a comparison of the results obtained for the four fossil fuel cycles together with results from the nuclear and renewable fuel cycles. This project is at the forefront of work in this area. It has drawn together an extensive multidisciplinary team of environmental scientists, energy technologists, health and ecology experts, atmospheric modellers, economists and computer analysts. The results obtained are based on thorough review of scientific and economic studies. This does not mean that exact values have been established for external costs. Indeed, one of our most important conclusions is that the uncertainties are large. Previous analyses

  14. Visual Memories Bypass Normalization.

    Science.gov (United States)

    Bloem, Ilona M; Watanabe, Yurika L; Kibbe, Melissa M; Ling, Sam

    2018-05-01

    How distinct are visual memory representations from visual perception? Although evidence suggests that briefly remembered stimuli are represented within early visual cortices, the degree to which these memory traces resemble true visual representations remains something of a mystery. Here, we tested whether both visual memory and perception succumb to a seemingly ubiquitous neural computation: normalization. Observers were asked to remember the contrast of visual stimuli, which were pitted against each other to promote normalization either in perception or in visual memory. Our results revealed robust normalization between visual representations in perception, yet no signature of normalization occurring between working memory stores-neither between representations in memory nor between memory representations and visual inputs. These results provide unique insight into the nature of visual memory representations, illustrating that visual memory representations follow a different set of computational rules, bypassing normalization, a canonical visual computation.

  15. SUBJECTIVE MEMORY IN OLDER AFRICAN AMERICANS

    OpenAIRE

    Sims, Regina C.; Whitfield, Keith E.; Ayotte, Brian J.; Gamaldo, Alyssa A.; Edwards, Christopher L.; Allaire, Jason C.

    2011-01-01

    The current analysis examined (a) if measures of psychological well-being predict subjective memory, and (b) if subjective memory is consistent with actual memory. Five hundred seventy-nine older African Americans from the Baltimore Study of Black Aging completed measures assessing subjective memory, depressive symptomatology, perceived stress, locus of control, and verbal and working memory. Higher levels of perceived stress and greater externalized locus of control predicted poorer subjecti...

  16. Episodic memory, semantic memory, and amnesia.

    Science.gov (United States)

    Squire, L R; Zola, S M

    1998-01-01

    Episodic memory and semantic memory are two types of declarative memory. There have been two principal views about how this distinction might be reflected in the organization of memory functions in the brain. One view, that episodic memory and semantic memory are both dependent on the integrity of medial temporal lobe and midline diencephalic structures, predicts that amnesic patients with medial temporal lobe/diencephalic damage should be proportionately impaired in both episodic and semantic memory. An alternative view is that the capacity for semantic memory is spared, or partially spared, in amnesia relative to episodic memory ability. This article reviews two kinds of relevant data: 1) case studies where amnesia has occurred early in childhood, before much of an individual's semantic knowledge has been acquired, and 2) experimental studies with amnesic patients of fact and event learning, remembering and knowing, and remote memory. The data provide no compelling support for the view that episodic and semantic memory are affected differently in medial temporal lobe/diencephalic amnesia. However, episodic and semantic memory may be dissociable in those amnesic patients who additionally have severe frontal lobe damage.

  17. Music evokes vivid autobiographical memories.

    Science.gov (United States)

    Belfi, Amy M; Karlan, Brett; Tranel, Daniel

    2016-08-01

    Music is strongly intertwined with memories-for example, hearing a song from the past can transport you back in time, triggering the sights, sounds, and feelings of a specific event. This association between music and vivid autobiographical memory is intuitively apparent, but the idea that music is intimately tied with memories, seemingly more so than other potent memory cues (e.g., familiar faces), has not been empirically tested. Here, we compared memories evoked by music to those evoked by famous faces, predicting that music-evoked autobiographical memories (MEAMs) would be more vivid. Participants listened to 30 songs, viewed 30 faces, and reported on memories that were evoked. Memories were transcribed and coded for vividness as in Levine, B., Svoboda, E., Hay, J. F., Winocur, G., & Moscovitch, M. [2002. Aging and autobiographical memory: Dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689]. In support of our hypothesis, MEAMs were more vivid than autobiographical memories evoked by faces. MEAMs contained a greater proportion of internal details and a greater number of perceptual details, while face-evoked memories contained a greater number of external details. Additionally, we identified sex differences in memory vividness: for both stimulus categories, women retrieved more vivid memories than men. The results show that music not only effectively evokes autobiographical memories, but that these memories are more vivid than those evoked by famous faces.

  18. Organization of the two-level memory in the image processing system on scanning measuring projectors

    International Nuclear Information System (INIS)

    Sychev, A.Yu.

    1977-01-01

    Discussed are the problems of improving the efficiency of the system for processing pictures taken in bubble chambers with the use of scanning measuring projectors. The system comprises 20 to 30 pro ectors linked with the ICL-1903A computer provided with a mainframe memory, 64 kilobytes in size. Because of the insufficient size of a mainframe memory, a part of the programs and data is located in a second-level memory, i.e. in an external memory. The analytical model described herein is used to analyze the effect of the memory organization on the characteristics of the system. It is shown that organization of pure procedures and introduction of the centralized control of the tWo-leVel memory result in substantial improvement of the efficiency of the picture processing system

  19. Prefrontal Neurons Represent Motion Signals from Across the Visual Field But for Memory-Guided Comparisons Depend on Neurons Providing These Signals.

    Science.gov (United States)

    Wimmer, Klaus; Spinelli, Philip; Pasternak, Tatiana

    2016-09-07

    Visual decisions often involve comparisons of sequential stimuli that can appear at any location in the visual field. The lateral prefrontal cortex (LPFC) in nonhuman primates, shown to play an important role in such comparisons, receives information about contralateral stimuli directly from sensory neurons in the same hemisphere, and about ipsilateral stimuli indirectly from neurons in the opposite hemisphere. This asymmetry of sensory inputs into the LPFC poses the question of whether and how its neurons incorporate sensory information arriving from the two hemispheres during memory-guided comparisons of visual motion. We found that, although responses of individual LPFC neurons to contralateral stimuli were stronger and emerged 40 ms earlier, they carried remarkably similar signals about motion direction in the two hemifields, with comparable direction selectivity and similar direction preferences. This similarity was also apparent around the time of the comparison between the current and remembered stimulus because both ipsilateral and contralateral responses showed similar signals reflecting the remembered direction. However, despite availability in the LPFC of motion information from across the visual field, these "comparison effects" required for the comparison stimuli to appear at the same retinal location. This strict dependence on spatial overlap of the comparison stimuli suggests participation of neurons with localized receptive fields in the comparison process. These results suggest that while LPFC incorporates many key aspects of the information arriving from sensory neurons residing in opposite hemispheres, it continues relying on the interactions with these neurons at the time of generating signals leading to successful perceptual decisions. Visual decisions often involve comparisons of sequential visual motion that can appear at any location in the visual field. We show that during such comparisons, the lateral prefrontal cortex (LPFC) contains

  20. Memory-guided attention: Control from multiple memory systems

    OpenAIRE

    Hutchinson, J. Benjamin; Turk-Browne, Nicholas B.

    2012-01-01

    Attention is strongly influenced by both external stimuli and internal goals. However, this useful dichotomy does not readily capture the ubiquitous and often automatic contribution of past experience stored in memory. We review recent evidence about how multiple memory systems control attention, consider how such interactions are manifested in the brain, and highlight how this framework for ‘memory-guided attention’ might help systematize previous findings and guide future research.

  1. Performance Targets and External Benchmarking

    DEFF Research Database (Denmark)

    Friis, Ivar; Hansen, Allan; Vámosi, Tamás S.

    Research on relative performance measures, transfer pricing, beyond budgeting initiatives, target costing, piece rates systems and value based management has for decades underlined the importance of external benchmarking in performance management. Research conceptualises external benchmarking...... as a market mechanism that can be brought inside the firm to provide incentives for continuous improvement and the development of competitive advances. However, whereas extant research primarily has focused on the importance and effects of using external benchmarks, less attention has been directed towards...... the conditions upon which the market mechanism is performing within organizations. This paper aims to contribute to research by providing more insight to the conditions for the use of external benchmarking as an element in performance management in organizations. Our study explores a particular type of external...

  2. Emerging non-volatile memories

    CERN Document Server

    Hong, Seungbum; Wouters, Dirk

    2014-01-01

    This book is an introduction to the fundamentals of emerging non-volatile memories and provides an overview of future trends in the field. Readers will find coverage of seven important memory technologies, including Ferroelectric Random Access Memory (FeRAM), Ferromagnetic RAM (FMRAM), Multiferroic RAM (MFRAM), Phase-Change Memories (PCM), Oxide-based Resistive RAM (RRAM), Probe Storage, and Polymer Memories. Chapters are structured to reflect diffusions and clashes between different topics. Emerging Non-Volatile Memories is an ideal book for graduate students, faculty, and professionals working in the area of non-volatile memory. This book also: Covers key memory technologies, including Ferroelectric Random Access Memory (FeRAM), Ferromagnetic RAM (FMRAM), and Multiferroic RAM (MFRAM), among others. Provides an overview of non-volatile memory fundamentals. Broadens readers' understanding of future trends in non-volatile memories.

  3. Enhancing Assisted Living Technology with Extended Visual Memory

    Directory of Open Access Journals (Sweden)

    Joo-Hwee Lim

    2011-05-01

    Full Text Available Human vision and memory are powerful cognitive faculties by which we understand the world. However, they are imperfect and further, subject to deterioration with age. We propose a cognitive-inspired computational model, Extended Visual Memory (EVM, within the Computer-Aided Vision (CAV framework, to assist human in vision-related tasks. We exploit wearable sensors such as cameras, GPS and ambient computing facilities to complement a user's vision and memory functions by answering four types of queries central to visual activities, namely, Retrieval, Understanding, Navigation and Search. Learning of EVM relies on both frequency-based and attention-driven mechanisms to store view-based visual fragments (VF, which are abstracted into high-level visual schemas (VS, both in the visual long-term memory. During inference, the visual short-term memory plays a key role in visual similarity computation between input (or its schematic representation and VF, exemplified from VS when necessary. We present an assisted living scenario, termed EViMAL (Extended Visual Memory for Assisted Living, targeted at mild dementia patients to provide novel functions such as hazard-warning, visual reminder, object look-up and event review. We envisage EVM having the potential benefits in alleviating memory loss, improving recall precision and enhancing memory capacity through external support.

  4. Memory architecture

    NARCIS (Netherlands)

    2012-01-01

    A memory architecture is presented. The memory architecture comprises a first memory and a second memory. The first memory has at least a bank with a first width addressable by a single address. The second memory has a plurality of banks of a second width, said banks being addressable by components

  5. The ethics of molecular memory modification.

    Science.gov (United States)

    Hui, Katrina; Fisher, Carl E

    2015-07-01

    Novel molecular interventions have recently shown the potential to erase, enhance and alter specific long-term memories. Unique features of this form of memory modification call for a close examination of its possible applications. While there have been discussions of the ethics of memory modification in the literature, molecular memory modification (MMM) can provide special insights. Previously raised ethical concerns regarding memory enhancement, such as safety issues, the 'duty to remember', selfhood and personal identity, require re-evaluation in light of MMM. As a technology that exploits the brain's updating processes, MMM helps correct the common misconception that memory is a static entity by demonstrating how memory is plastic and subject to revision even in the absence of external manipulation. Furthermore, while putatively safer than other speculative technologies because of its high specificity, MMM raises notable safety issues, including potential insidious effects on the agent's emotions and personal identity. Nonetheless, MMM possesses characteristics of a more permissible form of modification, not only because it is theoretically safer, but because its unique mechanism of action requires a heightened level of cooperation from the agent. Discussions of memory modification must consider the specific mechanisms of action, which can alter the weight and relevance of various ethical concerns. MMM also highlights the need for conceptual accuracy regarding the term 'enhancement'; this umbrella term will have to be differentiated as new technologies are applied to a widening array of purposes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  6. The ExternE project: methodology, objectives and limitations

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2002-01-01

    This paper presents a summary of recent studies on external costs of energy systems, in particular the ExternE (External Costs of Energy) Project of the European Commission. To evaluate the impact and damage cost of a pollutant, one needs to carry out an impact pathway analysis; this involves the calculation of increased pollutant concentrations in all affected regions due to an incremental emission (e.g. μg/m 3 of particles, using models of atmospheric dispersion and chemistry), followed by the calculation of physical impacts (e.g. number of cases of asthma due to these particles, using a dose-response function). The entire so-called fuel chain (or fuel cycle) is evaluated and compared on the basis of delivered end use energy. Even though the uncertainties are large, the results provide substantial evidence that the classical air pollutants (particles, NO x and SO x ) from the combustion of fossil fuels impose a heavy toll, in addition to the cost of global warming. The external costs are especially large for coal; even for 'good current technology' they may be comparable to the price of electricity. For natural gas the external costs are about a third to a half of coal. The external costs of nuclear are small compared to the price of electricity (at most a few %), and so are the external costs of most renewable energy systems. (authors)

  7. Malignant external otitis: CT evaluation

    International Nuclear Information System (INIS)

    Curtin, H.D.; Wolfe, P.; May, M.

    1982-01-01

    Malignant external otitis is an aggressive infection caused by Pseudomonas aeruginosa that most often occurs in elderly diabetics. Malignant external otitis often spreads inferiorly from the external canal to involve the subtemporal area and progresses medially towards the petrous apex leading to multiple cranial nerve palsies. The computed tomographic (CT) findings in malignant external otitis include obliteration of the normal fat planes in the subtemporal area as well as patchy destruction of the bony cortex of the mastoid. The point of exit of the various cranial nerves can be identified on CT scans, and the extent of the inflammatory mass correlates well with the clinical findings. Four cases of malignant external otitis are presented. In each case CT provided a good demonstration of involvement of the soft tissues at the base of the skull

  8. Exploring the effect of sleep and reduced interference on different forms of declarative memory.

    Science.gov (United States)

    Schönauer, Monika; Pawlizki, Annedore; Köck, Corinna; Gais, Steffen

    2014-12-01

    Many studies have found that sleep benefits declarative memory consolidation. However, fundamental questions on the specifics of this effect remain topics of discussion. It is not clear which forms of memory are affected by sleep and whether this beneficial effect is partly mediated by passive protection against interference. Moreover, a putative correlation between the structure of sleep and its memory-enhancing effects is still being discussed. In three experiments, we tested whether sleep differentially affects various forms of declarative memory. We varied verbal content (verbal/nonverbal), item type (single/associate), and recall mode (recall/recognition, cued/free recall) to examine the effect of sleep on specific memory subtypes. We compared within-subject differences in memory consolidation between intervals including sleep, active wakefulness, or quiet meditation, which reduced external as well as internal interference and rehearsal. Forty healthy adults aged 18-30 y, and 17 healthy adults aged 24-55 y with extensive meditation experience participated in the experiments. All types of memory were enhanced by sleep if the sample size provided sufficient statistical power. Smaller sample sizes showed an effect of sleep if a combined measure of different declarative memory scales was used. In a condition with reduced external and internal interference, performance was equal to one with high interference. Here, memory consolidation was significantly lower than in a sleep condition. We found no correlation between sleep structure and memory consolidation. Sleep does not preferentially consolidate a specific kind of declarative memory, but consistently promotes overall declarative memory formation. This effect is not mediated by reduced interference. © 2014 Associated Professional Sleep Societies, LLC.

  9. External costs of energy - do the answers match the questions? Looking back at 10 years of ExternE

    International Nuclear Information System (INIS)

    Krewitt, W.

    2002-01-01

    While the claim for 'getting prices right' is quite popular in conceptual policy papers, the implementation of appropriate internalisation strategies is still hampered by a lack of reliable external cost data. Great expectations were set into the ExternE project, a major research programme launched by the European Commission at the beginning of the 1990s to provide a scientific basis for the quantification of energy related externalities and to give guidance supporting the design of internalisation measures. After more than a decade of research, the ExternE label became a well recognised standard source for external cost data. Looking back into the ExternE history, the paper pursues how emerging new scientific insights and changing background assumptions affected external cost estimates and related recommendations to policy over time. Based on ExternE results, the usefulness and inherent limitations of external cost estimates for impact categories like climate change or nuclear waste disposal is discussed. The paper also gives examples on how external costs in spite of remaining uncertainties are successfully used to support environmental policy. (Author)

  10. External parallel sorting with multiprocessor computers

    International Nuclear Information System (INIS)

    Comanceau, S.I.

    1984-01-01

    This article describes methods of external sorting in which the entire main computer memory is used for the internal sorting of entries, forming out of them sorted segments of the greatest possible size, and outputting them to external memories. The obtained segments are merged into larger segments until all entries form one ordered segment. The described methods are suitable for sequential files stored on magnetic tape. The needs of the sorting algorithm can be met by using the relatively slow peripheral storage devices (e.g., tapes, disks, drums). The efficiency of the external sorting methods is determined by calculating the total sorting time as a function of the number of entries to be sorted and the number of parallel processors participating in the sorting process

  11. An Artificial Flexible Visual Memory System Based on an UV-Motivated Memristor.

    Science.gov (United States)

    Chen, Shuai; Lou, Zheng; Chen, Di; Shen, Guozhen

    2018-02-01

    For the mimicry of human visual memory, a prominent challenge is how to detect and store the image information by electronic devices, which demands a multifunctional integration to sense light like eyes and to memorize image information like the brain by transforming optical signals to electrical signals that can be recognized by electronic devices. Although current image sensors can perceive simple images in real time, the image information fades away when the external image stimuli are removed. The deficiency between the state-of-the-art image sensors and visual memory system inspires the logical integration of image sensors and memory devices to realize the sensing and memory process toward light information for the bionic design of human visual memory. Hence, a facile architecture is designed to construct artificial flexible visual memory system by employing an UV-motivated memristor. The visual memory arrays can realize the detection and memory process of UV light distribution with a patterned image for a long-term retention and the stored image information can be reset by a negative voltage sweep and reprogrammed to the same or an other image distribution, which proves the effective reusability. These results provide new opportunities for the mimicry of human visual memory and enable the flexible visual memory device to be applied in future wearable electronics, electronic eyes, multifunctional robotics, and auxiliary equipment for visual handicapped. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Method for refreshing a non-volatile memory

    Science.gov (United States)

    Riekels, James E.; Schlesinger, Samuel

    2008-11-04

    A non-volatile memory and a method of refreshing a memory are described. The method includes allowing an external system to control refreshing operations within the memory. The memory may generate a refresh request signal and transmit the refresh request signal to the external system. When the external system finds an available time to process the refresh request, the external system acknowledges the refresh request and transmits a refresh acknowledge signal to the memory. The memory may also comprise a page register for reading and rewriting a data state back to the memory. The page register may comprise latches in lieu of supplemental non-volatile storage elements, thereby conserving real estate within the memory.

  13. Conceptual challenges for internalising externalities

    DEFF Research Database (Denmark)

    Miguel, Brandão; Weidema, Bo Pedersen

    2013-01-01

    We analyse a number of different externalities to identify conceptual challenges for the practical implementation of their internalisation. Three issues were identified: i) The balance between compensation and technology change and the respective effects on the nominal and real GDP; ii...... geographical and especially temporal distance between the benefitting actor and the victim of the external cost, the involvement of a non-governmental intermediate actor becomes increasingly necessary to provide the short-term capital required to ensure a successful implementation....

  14. Real-time stereo matching architecture based on 2D MRF model: a memory-efficient systolic array

    Directory of Open Access Journals (Sweden)

    Park Sungchan

    2011-01-01

    Full Text Available Abstract There is a growing need in computer vision applications for stereopsis, requiring not only accurate distance but also fast and compact physical implementation. Global energy minimization techniques provide remarkably precise results. But they suffer from huge computational complexity. One of the main challenges is to parallelize the iterative computation, solving the memory access problem between the big external memory and the massive processors. Remarkable memory saving can be obtained with our memory reduction scheme, and our new architecture is a systolic array. If we expand it into N's multiple chips in a cascaded manner, we can cope with various ranges of image resolutions. We have realized it using the FPGA technology. Our architecture records 19 times smaller memory than the global minimization technique, which is a principal step toward real-time chip implementation of the various iterative image processing algorithms with tiny and distributed memory resources like optical flow, image restoration, etc.

  15. 3D Printed Photoresponsive Devices Based on Shape Memory Composites.

    Science.gov (United States)

    Yang, Hui; Leow, Wan Ru; Wang, Ting; Wang, Juan; Yu, Jiancan; He, Ke; Qi, Dianpeng; Wan, Changjin; Chen, Xiaodong

    2017-09-01

    Compared with traditional stimuli-responsive devices with simple planar or tubular geometries, 3D printed stimuli-responsive devices not only intimately meet the requirement of complicated shapes at macrolevel but also satisfy various conformation changes triggered by external stimuli at the microscopic scale. However, their development is limited by the lack of 3D printing functional materials. This paper demonstrates the 3D printing of photoresponsive shape memory devices through combining fused deposition modeling printing technology and photoresponsive shape memory composites based on shape memory polymers and carbon black with high photothermal conversion efficiency. External illumination triggers the shape recovery of 3D printed devices from the temporary shape to the original shape. The effect of materials thickness and light density on the shape memory behavior of 3D printed devices is quantified and calculated. Remarkably, sunlight also triggers the shape memory behavior of these 3D printed devices. This facile printing strategy would provide tremendous opportunities for the design and fabrication of biomimetic smart devices and soft robotics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. MEMORY MODULATION

    Science.gov (United States)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145

  17. Memory Matters

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Memory Matters KidsHealth / For Kids / Memory Matters What's in ... of your complex and multitalented brain. What Is Memory? When an event happens, when you learn something, ...

  18. Regulating multiple externalities

    DEFF Research Database (Denmark)

    Waldo, Staffan; Jensen, Frank; Nielsen, Max

    2016-01-01

    Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory instrume......Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory...

  19. Making Memories Matter

    OpenAIRE

    Gold, Paul E.; Korol, Donna L.

    2012-01-01

    This article reviews some of the neuroendocrine bases by which emotional events regulate brain mechanisms of learning and memory. In laboratory rodents, there is extensive evidence that epinephrine influences memory processing through an inverted-U relationship, at which moderate levels enhance and high levels impair memory. These effects are, in large part, mediated by increases in blood glucose levels subsequent to epinephrine release, which then provide support for the brain processes en...

  20. Memory T Cell Migration

    OpenAIRE

    Qianqian eZhang; Qianqian eZhang; Fadi G. Lakkis

    2015-01-01

    Immunological memory is a key feature of adaptive immunity. It provides the organism with long-lived and robust protection against infection. In organ transplantation, memory T cells pose a significant threat by causing allograft rejection that is generally resistant to immunosuppressive therapy. Therefore, a more thorough understanding of memory T cell biology is needed to improve the survival of transplanted organs without compromising the host’s ability to fight infections. This review...

  1. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K; Maelkki, H; Wihersaari, M; Pirilae, P [VTT Energy, Espoo (Finland); Hongisto, M [Imatran Voima Oy, Vantaa (Finland); Siitonen, S [Ekono Energy Ltd, Espoo (Finland); Johansson, M [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  2. ExternE National Implementation Finland

    International Nuclear Information System (INIS)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P.; Hongisto, M.; Siitonen, S.; Johansson, M.

    1999-01-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  3. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P. [VTT Energy, Espoo (Finland); Hongisto, M. [Imatran Voima Oy, Vantaa (Finland); Siitonen, S. [Ekono Energy Ltd, Espoo (Finland); Johansson, M. [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  4. Radiation-Tolerant Intelligent Memory Stack - RTIMS

    Science.gov (United States)

    Ng, Tak-kwong; Herath, Jeffrey A.

    2011-01-01

    This innovation provides reconfigurable circuitry and 2-Gb of error-corrected or 1-Gb of triple-redundant digital memory in a small package. RTIMS uses circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field-programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuits are stacked into a module of 42.7 42.7 13 mm. Triple module redundancy, current limiting, configuration scrubbing, and single- event function interrupt detection are employed to mitigate radiation effects. The novel self-scrubbing and single event functional interrupt (SEFI) detection allows a relatively soft FPGA to become radiation tolerant without external scrubbing and monitoring hardware

  5. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... otitis. Fungal external otitis (otomycosis), typically caused by Aspergillus niger or Candida albicans, is less common. Boils are ... in the ear. Fungal external otitis caused by Aspergillus niger usually causes grayish black or yellow dots (called ...

  6. Shape memory polymers

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Thomas S.; Bearinger, Jane P.

    2017-08-29

    New shape memory polymer compositions, methods for synthesizing new shape memory polymers, and apparatus comprising an actuator and a shape memory polymer wherein the shape memory polymer comprises at least a portion of the actuator. A shape memory polymer comprising a polymer composition which physically forms a network structure wherein the polymer composition has shape-memory behavior and can be formed into a permanent primary shape, re-formed into a stable secondary shape, and controllably actuated to recover the permanent primary shape. Polymers have optimal aliphatic network structures due to minimization of dangling chains by using monomers that are symmetrical and that have matching amine and hydroxl groups providing polymers and polymer foams with clarity, tight (narrow temperature range) single transitions, and high shape recovery and recovery force that are especially useful for implanting in the human body.

  7. Shape memory polymers

    Science.gov (United States)

    Wilson, Thomas S.; Bearinger, Jane P.

    2015-06-09

    New shape memory polymer compositions, methods for synthesizing new shape memory polymers, and apparatus comprising an actuator and a shape memory polymer wherein the shape memory polymer comprises at least a portion of the actuator. A shape memory polymer comprising a polymer composition which physically forms a network structure wherein the polymer composition has shape-memory behavior and can be formed into a permanent primary shape, re-formed into a stable secondary shape, and controllably actuated to recover the permanent primary shape. Polymers have optimal aliphatic network structures due to minimization of dangling chains by using monomers that are symmetrical and that have matching amine and hydroxyl groups providing polymers and polymer foams with clarity, tight (narrow temperature range) single transitions, and high shape recovery and recovery force that are especially useful for implanting in the human body.

  8. Memory and Perfection in Ferroelastic Inclusion Compounds

    International Nuclear Information System (INIS)

    Hollingsworth, M.; Peterson, M.; Rush, J.; Brown, M.; Abel, M.; Black, A.; Dudley, M.; Raghothamachar, B.; Werner-Zwanziger, U.

    2005-01-01

    In a series of ferroelastic urea inclusion compounds (UICs), in which domain reorientation occurs upon application of an external anisotropic force, introduction of a relaxive impurity that disrupts a specific hydrogen-bonding network transforms a plastic (irreversible) domain-switching process into one that exhibits a striking memory effect and 'rubber-like behavior', a form of pseudoelasticity. As expected for a highly cooperative process, the ferroelastic response to the impurity concentration exhibits a critical threshold. Through synchrotron white-beam X-ray topography (SWBXT) of crystals under stress, videomicroscopy of spontaneous repair during crystal growth, acoustomechanical relaxation of daughter domains, kinetic measurements of spontaneous domain reversion, and solid-state 2 H NMR of labeled guests, this work shows how relaxive impurities lower the barrier to domain switching and how differences in perfection between mother and daughter domains provide the driving force for the memory effects. Although the interfacial effects implicated here are different from the volume effects that operate in certain shape memory materials, the twinning and defect phenomena responsible for the rubber-like behavior and memory effects should be generally applicable to domain switching in ferroelastic and ferroelectric crystals and to other solid-state processes

  9. Single Canonical Model of Reflexive Memory and Spatial Attention

    Science.gov (United States)

    Patel, Saumil S.; Red, Stuart; Lin, Eric; Sereno, Anne B.

    2015-01-01

    Many neurons in the dorsal and ventral visual stream have the property that after a brief visual stimulus presentation in their receptive field, the spiking activity in these neurons persists above their baseline levels for several seconds. This maintained activity is not always correlated with the monkey’s task and its origin is unknown. We have previously proposed a simple neural network model, based on shape selective neurons in monkey lateral intraparietal cortex, which predicts the valence and time course of reflexive (bottom-up) spatial attention. In the same simple model, we demonstrate here that passive maintained activity or short-term memory of specific visual events can result without need for an external or top-down modulatory signal. Mutual inhibition and neuronal adaptation play distinct roles in reflexive attention and memory. This modest 4-cell model provides the first simple and unified physiologically plausible mechanism of reflexive spatial attention and passive short-term memory processes. PMID:26493949

  10. Single Canonical Model of Reflexive Memory and Spatial Attention.

    Science.gov (United States)

    Patel, Saumil S; Red, Stuart; Lin, Eric; Sereno, Anne B

    2015-10-23

    Many neurons in the dorsal and ventral visual stream have the property that after a brief visual stimulus presentation in their receptive field, the spiking activity in these neurons persists above their baseline levels for several seconds. This maintained activity is not always correlated with the monkey's task and its origin is unknown. We have previously proposed a simple neural network model, based on shape selective neurons in monkey lateral intraparietal cortex, which predicts the valence and time course of reflexive (bottom-up) spatial attention. In the same simple model, we demonstrate here that passive maintained activity or short-term memory of specific visual events can result without need for an external or top-down modulatory signal. Mutual inhibition and neuronal adaptation play distinct roles in reflexive attention and memory. This modest 4-cell model provides the first simple and unified physiologically plausible mechanism of reflexive spatial attention and passive short-term memory processes.

  11. Shape memory materials

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Compared with piezoelectric ceramics and magnetostrictive materials, the shape memory materials possess larger recoverable strain and recovery stress but slower response to external field. It is expected that the magneto-shape memory materials may develop considerable strain as well as rapid and precise shape control. Pseudoelasticity and shape memory effect (SME) resulted from martensitic transformation and its reverse transformation in shape memory materials were generally described. The requirements of appearing the shape memory effect in materials and the criteria for thermoelastic martensitic transformation were given. Some aspects concerning characteristics of martensitic transformation, and factors affecting SME in Ni-Ti, Cu-Zn-Al and Fe-Mn-Si based alloys as well as ZrO2 containing ceramics were briefly reviewed. Thermodynamic calculation of Ms temperature as function of grain size and parent ordering in Cu-Zn-Al was presented. The works on prediction of Ms in Fe-Mn-Si based alloys and in ZrO2-CeO2 were mentioned. Magnetic shape memory materials were briefly introduced.

  12. NPY2-receptor variation modulates iconic memory processes.

    Science.gov (United States)

    Arning, Larissa; Stock, Ann-Kathrin; Kloster, Eugen; Epplen, Jörg T; Beste, Christian

    2014-08-01

    Sensory memory systems are modality-specific buffers that comprise information about external stimuli, which represent the earliest stage of information processing. While these systems have been the subject of cognitive neuroscience research for decades, little is known about the neurobiological basis of sensory memory. However, accumulating evidence suggests that the glutamatergic system and systems influencing glutamatergic neural transmission are important. In the current study we examine if functional promoter variations in neuropeptide Y (NPY) and its receptor gene NPY2R affect iconic memory processes using a partial report paradigm. We found that iconic memory decayed much faster in individuals carrying the rare promoter NPY2R G allele which is associated with increased expression of the Y2 receptor. Possibly this effect is due to altered presynaptic inhibition of glutamate release, known to be modulated by Y2 receptors. Altogether, our results provide evidence that the functionally relevant single nucleotide polymorphism (SNP) in the NPY2R promoter gene affect circumscribed processes of early sensory processing, i.e. only the stability of information in sensory memory buffers. This leads us to suggest that especially the stability of information in sensory memory buffers depends on glutamatergic neural transmission and factors modulating glutamatergic turnover. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  13. Transactional Memory

    CERN Document Server

    Harris, Tim; Rajwar, Ravi

    2010-01-01

    The advent of multicore processors has renewed interest in the idea of incorporating transactions into the programming model used to write parallel programs.This approach, known as transactional memory, offers an alternative, and hopefully better, way to coordinate concurrent threads. The ACI(atomicity, consistency, isolation) properties of transactions provide a foundation to ensure that concurrent reads and writes of shared data do not produce inconsistent or incorrect results. At a higher level, a computation wrapped in a transaction executes atomically - either it completes successfullyand

  14. Organizing for External Knowledge Sourcing

    DEFF Research Database (Denmark)

    Rabbiosi, Larissa; Reichstein, Toke

    2011-01-01

    The aim of this article is to provide an introduction to the special issue. We briefly consider the external knowledge sourcing and organizing for innovation literatures, which offer a background for the special issue, and we highlight their mutual dialogue. We then illustrate the main findings o...

  15. Modularity in Sensory Auditory Memory

    OpenAIRE

    Clement, Sylvain; Moroni, Christine; Samson, Séverine

    2004-01-01

    The goal of this paper was to review various experimental and neuropsychological studies that support the modular conception of auditory sensory memory or auditory short-term memory. Based on initial findings demonstrating that verbal sensory memory system can be dissociated from a general auditory memory store at the functional and anatomical levels. we reported a series of studies that provided evidence in favor of multiple auditory sensory stores specialized in retaining eit...

  16. Involuntary memory chaining versus event cueing: Which is a better indicator of autobiographical memory organisation?

    Science.gov (United States)

    Mace, John H; Clevinger, Amanda M; Martin, Cody

    2010-11-01

    Involuntary memory chains are spontaneous recollections of the past that occur in a sequence. Much like semantic memory priming, this memory phenomenon has provided some insights into the nature of associations in autobiographical memory. The event-cueing procedure (a laboratory-based memory sequencing task) has also provided some insights into the nature of autobiographical memory organisation. However, while both of these memory-sequencing phenomena have exhibited the same types of memory associations (conceptual associations and general-event or temporal associations), both have also produced discrepant results with respect to the relative proportions of such associations. This study investigated the possibility that the results from event cueing are artefacts of various memory production responses. Using a number of different approaches we demonstrated that these memory production responses cause overestimates of general-event association. We conclude that for this reason, the data from involuntary memory chains provide a better picture of the organisation of autobiographical memory.

  17. Short-term memories with a stochastic perturbation

    International Nuclear Information System (INIS)

    Pontes, Jose C.A. de; Batista, Antonio M.; Viana, Ricardo L.; Lopes, Sergio R.

    2005-01-01

    We investigate short-term memories in linear and weakly nonlinear coupled map lattices with a periodic external input. We use locally coupled maps to present numerical results about short-term memory formation adding a stochastic perturbation in the maps and in the external input

  18. Medicare Provider Data - Hospice Providers

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Hospice Utilization and Payment Public Use File provides information on services provided to Medicare beneficiaries by hospice providers. The Hospice PUF...

  19. External radiation surveillance

    International Nuclear Information System (INIS)

    Antonio, E.J.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site

  20. External radiation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  1. Memory for speech and speech for memory.

    Science.gov (United States)

    Locke, J L; Kutz, K J

    1975-03-01

    Thirty kindergarteners, 15 who substituted /w/ for /r/ and 15 with correct articulation, received two perception tests and a memory test that included /w/ and /r/ in minimally contrastive syllables. Although both groups had nearly perfect perception of the experimenter's productions of /w/ and /r/, misarticulating subjects perceived their own tape-recorded w/r productions as /w/. In the memory task these same misarticulating subjects committed significantly more /w/-/r/ confusions in unspoken recall. The discussion considers why people subvocally rehearse; a developmental period in which children do not rehearse; ways subvocalization may aid recall, including motor and acoustic encoding; an echoic store that provides additional recall support if subjects rehearse vocally, and perception of self- and other- produced phonemes by misarticulating children-including its relevance to a motor theory of perception. Evidence is presented that speech for memory can be sufficiently impaired to cause memory disorder. Conceptions that restrict speech disorder to an impairment of communication are challenged.

  2. ExternE: Externalities of energy Vol. 5. Nuclear

    International Nuclear Information System (INIS)

    Dreicer, M.; Tort, V.; Manen, P.

    1995-01-01

    Since the early 1970s, there has been increased interest in the environmental impacts that are caused by the generation of electricity. The comparative risk assessment studies at that time used mainly deaths and injuries as impact indicators. By the end of the 1980s studies changed to the assessment of the costs imposed on society and the environment that were not included in the market price of the energy produced, the so-called external costs. The preliminary studies that were published set the conceptual basis, grounded in neo-classical economics, for the valuation of the health and environmental impacts that could be assessed. As a consequence of the many questions raised by the methodologies employed by these early studies, Directorate General XII (DG XII) of the Commission of the European Communities established a collaborative research programme with the United States Department of Energy to identify an appropriate methodology for this type of work. Following the completion of this collaboration, the DG XII programme has continued as the ExternE project. The main objective of the work carried out at CEPN was to develop an impact pathway methodology for the nuclear fuel cycle that would be consistent with the methodologies developed for other fuel cycles, without loosing the nuclear-specific techniques required for a proper evaluation. In this way, comparisons between the different fuel cycles would be possible. This report presents the methodology and demonstration of the results in the context of the French nuclear fuel cycle. The United States team at Oak Ridge National Laboratory has previously issued a draft report on the results of their assessment. The French fuel cycle was broken down into 8 separate stages. Reference sites and 1990s technology were chosen to represent the total nuclear fuel cycle, as it exists today. In addition, the transportation of material between the sites was considered. The facilities are assessed for routine operation, except

  3. Cognitive memory.

    Science.gov (United States)

    Widrow, Bernard; Aragon, Juan Carlos

    2013-05-01

    Regarding the workings of the human mind, memory and pattern recognition seem to be intertwined. You generally do not have one without the other. Taking inspiration from life experience, a new form of computer memory has been devised. Certain conjectures about human memory are keys to the central idea. The design of a practical and useful "cognitive" memory system is contemplated, a memory system that may also serve as a model for many aspects of human memory. The new memory does not function like a computer memory where specific data is stored in specific numbered registers and retrieval is done by reading the contents of the specified memory register, or done by matching key words as with a document search. Incoming sensory data would be stored at the next available empty memory location, and indeed could be stored redundantly at several empty locations. The stored sensory data would neither have key words nor would it be located in known or specified memory locations. Sensory inputs concerning a single object or subject are stored together as patterns in a single "file folder" or "memory folder". When the contents of the folder are retrieved, sights, sounds, tactile feel, smell, etc., are obtained all at the same time. Retrieval would be initiated by a query or a prompt signal from a current set of sensory inputs or patterns. A search through the memory would be made to locate stored data that correlates with or relates to the prompt input. The search would be done by a retrieval system whose first stage makes use of autoassociative artificial neural networks and whose second stage relies on exhaustive search. Applications of cognitive memory systems have been made to visual aircraft identification, aircraft navigation, and human facial recognition. Concerning human memory, reasons are given why it is unlikely that long-term memory is stored in the synapses of the brain's neural networks. Reasons are given suggesting that long-term memory is stored in DNA or RNA

  4. Single memory with multiple shift register functionality

    NARCIS (Netherlands)

    2010-01-01

    The present invention relates to a memory device comprising a memory (EM) having at least two predetermined register memory sections addressable by respective address ranges AS1-ASz) and at least one access port (P1-PZ) for providing access to said memory (EM). Furthermore, access control means (A)

  5. Making memories matter

    Directory of Open Access Journals (Sweden)

    Paul E. Gold

    2012-12-01

    Full Text Available This article reviews some of the neuroendocrine bases by which emotional events regulate brain mechanisms of learning and memory. In laboratory rodents, there is extensive evidence that epinephrine influences memory processing through an inverted-U relationship, at which moderate levels enhance and high levels impair memory. These effects are, in large part, mediated by increases in blood glucose levels subsequent to epinephrine release, which then provide support for the brain processes engaged by learning and memory. These brain processes include augmentation of neurotransmitter release and of energy metabolism, the latter apparently including a key role for astrocytic glycogen. In addition to up- and down-regulation of learning and memory in general, physiological concomitants of emotion and arousal can also switch the neural system that controls learning at a particular time, at once improving some attributes of learning and impairing others in a manner that results in a change in the strategy used to solve a problem.

  6. Making Memories Matter

    Science.gov (United States)

    Gold, Paul E.; Korol, Donna L.

    2012-01-01

    This article reviews some of the neuroendocrine bases by which emotional events regulate brain mechanisms of learning and memory. In laboratory rodents, there is extensive evidence that epinephrine influences memory processing through an inverted-U relationship, at which moderate levels enhance and high levels impair memory. These effects are, in large part, mediated by increases in blood glucose levels subsequent to epinephrine release, which then provide support for the brain processes engaged by learning and memory. These brain processes include augmentation of neurotransmitter release and of energy metabolism, the latter apparently including a key role for astrocytic glycogen. In addition to up- and down-regulation of learning and memory in general, physiological concomitants of emotion and arousal can also switch the neural system that controls learning at a particular time, at once improving some attributes of learning and impairing others in a manner that results in a change in the strategy used to solve a problem. PMID:23264764

  7. Learning and memory.

    Science.gov (United States)

    Brem, Anna-Katharine; Ran, Kathy; Pascual-Leone, Alvaro

    2013-01-01

    Learning and memory functions are crucial in the interaction of an individual with the environment and involve the interplay of large, distributed brain networks. Recent advances in technologies to explore neurobiological correlates of neuropsychological paradigms have increased our knowledge about human learning and memory. In this chapter we first review and define memory and learning processes from a neuropsychological perspective. Then we provide some illustrations of how noninvasive brain stimulation can play a major role in the investigation of memory functions, as it can be used to identify cause-effect relationships and chronometric properties of neural processes underlying cognitive steps. In clinical medicine, transcranial magnetic stimulation may be used as a diagnostic tool to understand memory and learning deficits in various patient populations. Furthermore, noninvasive brain stimulation is also being applied to enhance cognitive functions, offering exciting translational therapeutic opportunities in neurology and psychiatry. © 2013 Elsevier B.V. All rights reserved.

  8. Memory Modulation

    NARCIS (Netherlands)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive

  9. The memory of volatility

    Directory of Open Access Journals (Sweden)

    Kai R. Wenger

    2018-03-01

    Full Text Available The focus of the volatility literature on forecasting and the predominance of theconceptually simpler HAR model over long memory stochastic volatility models has led to the factthat the actual degree of memory estimates has rarely been considered. Estimates in the literaturerange roughly between 0.4 and 0.6 - that is from the higher stationary to the lower non-stationaryregion. This difference, however, has important practical implications - such as the existence or nonexistenceof the fourth moment of the return distribution. Inference on the memory order is complicatedby the presence of measurement error in realized volatility and the potential of spurious long memory.In this paper we provide a comprehensive analysis of the memory in variances of international stockindices and exchange rates. On the one hand, we find that the variance of exchange rates is subject tospurious long memory and the true memory parameter is in the higher stationary range. Stock indexvariances, on the other hand, are free of low frequency contaminations and the memory is in the lowernon-stationary range. These results are obtained using state of the art local Whittle methods that allowconsistent estimation in presence of perturbations or low frequency contaminations.

  10. Memory Dysfunction

    Science.gov (United States)

    Matthews, Brandy R.

    2015-01-01

    Purpose of Review: This article highlights the dissociable human memory systems of episodic, semantic, and procedural memory in the context of neurologic illnesses known to adversely affect specific neuroanatomic structures relevant to each memory system. Recent Findings: Advances in functional neuroimaging and refinement of neuropsychological and bedside assessment tools continue to support a model of multiple memory systems that are distinct yet complementary and to support the potential for one system to be engaged as a compensatory strategy when a counterpart system fails. Summary: Episodic memory, the ability to recall personal episodes, is the subtype of memory most often perceived as dysfunctional by patients and informants. Medial temporal lobe structures, especially the hippocampal formation and associated cortical and subcortical structures, are most often associated with episodic memory loss. Episodic memory dysfunction may present acutely, as in concussion; transiently, as in transient global amnesia (TGA); subacutely, as in thiamine deficiency; or chronically, as in Alzheimer disease. Semantic memory refers to acquired knowledge about the world. Anterior and inferior temporal lobe structures are most often associated with semantic memory loss. The semantic variant of primary progressive aphasia (svPPA) is the paradigmatic disorder resulting in predominant semantic memory dysfunction. Working memory, associated with frontal lobe function, is the active maintenance of information in the mind that can be potentially manipulated to complete goal-directed tasks. Procedural memory, the ability to learn skills that become automatic, involves the basal ganglia, cerebellum, and supplementary motor cortex. Parkinson disease and related disorders result in procedural memory deficits. Most memory concerns warrant bedside cognitive or neuropsychological evaluation and neuroimaging to assess for specific neuropathologies and guide treatment. PMID:26039844

  11. Transactive memory in organizational groups: the effects of content, consensus, specialization, and accuracy on group performance.

    Science.gov (United States)

    Austin, John R

    2003-10-01

    Previous research on transactive memory has found a positive relationship between transactive memory system development and group performance in single project laboratory and ad hoc groups. Closely related research on shared mental models and expertise recognition supports these findings. In this study, the author examined the relationship between transactive memory systems and performance in mature, continuing groups. A group's transactive memory system, measured as a combination of knowledge stock, knowledge specialization, transactive memory consensus, and transactive memory accuracy, is positively related to group goal performance, external group evaluations, and internal group evaluations. The positive relationship with group performance was found to hold for both task and external relationship transactive memory systems.

  12. High-bandwidth memory interface

    CERN Document Server

    Kim, Chulwoo; Song, Junyoung

    2014-01-01

    This book provides an overview of recent advances in memory interface design at both the architecture and circuit levels. Coverage includes signal integrity and testing, TSV interface, high-speed serial interface including equalization, ODT, pre-emphasis, wide I/O interface including crosstalk, skew cancellation, and clock generation and distribution. Trends for further bandwidth enhancement are also covered.   • Enables readers with minimal background in memory design to understand the basics of high-bandwidth memory interface design; • Presents state-of-the-art techniques for memory interface design; • Covers memory interface design at both the circuit level and system architecture level.

  13. [External cephalic version].

    Science.gov (United States)

    Navarro-Santana, B; Duarez-Coronado, M; Plaza-Arranz, J

    2016-08-01

    To analyze the rate of successful external cephalic versions in our center and caesarean sections that would be avoided with the use of external cephalic versions. From January 2012 to March 2016 external cephalic versions carried out at our center, which were a total of 52. We collected data about female age, gestational age at the time of the external cephalic version, maternal body mass index (BMI), fetal variety and situation, fetal weight, parity, location of the placenta, amniotic fluid index (ILA), tocolysis, analgesia, and newborn weight at birth, minor adverse effects (dizziness, hypotension and maternal pain) and major adverse effects (tachycardia, bradycardia, decelerations and emergency cesarean section). 45% of the versions were unsuccessful and 55% were successful. The percentage of successful vaginal delivery in versions was 84% (4% were instrumental) and 15% of caesarean sections. With respect to the variables studied, only significant differences in birth weight were found; suggesting that birth weight it is related to the outcome of external cephalic version. Probably we did not find significant differences due to the number of patients studied. For women with breech presentation, we recommend external cephalic version before the expectant management or performing a cesarean section. The external cephalic version increases the proportion of fetuses in cephalic presentation and also decreases the rate of caesarean sections.

  14. Piezosurgery in External Dacryocystorhinostomy.

    Science.gov (United States)

    Czyz, Craig N; Fowler, Amy M; Dutton, Jonathan J; Cahill, Kenneth V; Foster, Jill A; Hill, Robert H; Everman, Kelly R; Nabavi, Cameron B

    Dacryocystorhinostomy (DCR) can be performed via an external or endoscopic approach. The use of ultrasonic or piezosurgery has been well described for endoscopic DCRs but is lacking for external DCRs. This study presents a case series of external DCRs performed using piezosurgery evaluating results and complications. Prospective, consecutive case series of patients undergoing primary external DCR for lacrimal drainage insufficiency. A standard external DCR technique was used using 1 of 2 piezosurgery systems for all bone incision. All patients received silicone intubation to the lacrimal system. Surgical outcome was measured in terms of patient-reported epiphora as follows: 1) complete resolution, 2) improvement >50%, 3) improvement 50% improvement. There were 4 patients (7%) who had <50% improvement. There was 1 (2%) intraoperative complication and 2 (4%) postoperative complications recorded. Piezourgery is a viable modality for performing external DCRs. The lack of surgical complications shows a potential for decreased soft tissues damage. The surgical success rate based on patient-reported epiphora is similar to those published for mechanical external DCRs. This modality may benefit the novice surgeon in the reduction of soft and mucosal tissue damage.

  15. Declarative memory.

    Science.gov (United States)

    Riedel, Wim J; Blokland, Arjan

    2015-01-01

    Declarative Memory consists of memory for events (episodic memory) and facts (semantic memory). Methods to test declarative memory are key in investigating effects of potential cognition-enhancing substances--medicinal drugs or nutrients. A number of cognitive performance tests assessing declarative episodic memory tapping verbal learning, logical memory, pattern recognition memory, and paired associates learning are described. These tests have been used as outcome variables in 34 studies in humans that have been described in the literature in the past 10 years. Also, the use of episodic tests in animal research is discussed also in relation to the drug effects in these tasks. The results show that nutritional supplementation of polyunsaturated fatty acids has been investigated most abundantly and, in a number of cases, but not all, show indications of positive effects on declarative memory, more so in elderly than in young subjects. Studies investigating effects of registered anti-Alzheimer drugs, cholinesterase inhibitors in mild cognitive impairment, show positive and negative effects on declarative memory. Studies mainly carried out in healthy volunteers investigating the effects of acute dopamine stimulation indicate enhanced memory consolidation as manifested specifically by better delayed recall, especially at time points long after learning and more so when drug is administered after learning and if word lists are longer. The animal studies reveal a different picture with respect to the effects of different drugs on memory performance. This suggests that at least for episodic memory tasks, the translational value is rather poor. For the human studies, detailed parameters of the compositions of word lists for declarative memory tests are discussed and it is concluded that tailored adaptations of tests to fit the hypothesis under study, rather than "off-the-shelf" use of existing tests, are recommended.

  16. About sleep's role in memory.

    Science.gov (United States)

    Rasch, Björn; Born, Jan

    2013-04-01

    Over more than a century of research has established the fact that sleep benefits the retention of memory. In this review we aim to comprehensively cover the field of "sleep and memory" research by providing a historical perspective on concepts and a discussion of more recent key findings. Whereas initial theories posed a passive role for sleep enhancing memories by protecting them from interfering stimuli, current theories highlight an active role for sleep in which memories undergo a process of system consolidation during sleep. Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories. Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory. Ensuing REM sleep may stabilize transformed memories. While elaborated with respect to hippocampus-dependent memories, the concept of an active redistribution of memory representations from networks serving as temporary store into long-term stores might hold also for non-hippocampus-dependent memory, and even for nonneuronal, i.e., immunological memories, giving rise to the idea that the offline consolidation of memory during sleep represents a principle of long-term memory formation established in quite different physiological systems.

  17. Automated External Defibrillator

    Science.gov (United States)

    ... leads to a 10 percent reduction in survival. Training To Use an Automated External Defibrillator Learning how to use an AED and taking a CPR (cardiopulmonary resuscitation) course are helpful. However, if trained ...

  18. Energy policy and externalities

    International Nuclear Information System (INIS)

    Bertel, E.; Fraser, P.

    2002-01-01

    External costs of energy have been assessed in a number of authoritative and reliable studies based upon widely accepted methodologies such as life cycle analysis (LCA). However, although those costs are recognised by most stakeholders and decision makers, results from analytical work on externalities and LCA studies are seldom used in policy making. The International Energy Agency (IEA) and the Nuclear Energy Agency (NEA) convened a joint workshop in November 2001 to offer experts and policy makers an opportunity to present state-of-the-art results from analytical work on externalities and debate issues related to the relevance of external costs and LCA for policy-making purposes. The findings from the workshop highlight the need for further work in the field and the potential rote of international organisations like the IEA and the NEA in this context. (authors)

  19. Externally Verifiable Oblivious RAM

    Directory of Open Access Journals (Sweden)

    Gancher Joshua

    2017-04-01

    Full Text Available We present the idea of externally verifiable oblivious RAM (ORAM. Our goal is to allow a client and server carrying out an ORAM protocol to have disputes adjudicated by a third party, allowing for the enforcement of penalties against an unreliable or malicious server. We give a security definition that guarantees protection not only against a malicious server but also against a client making false accusations. We then give modifications of the Path ORAM [15] and Ring ORAM [9] protocols that meet this security definition. These protocols both have the same asymptotic runtimes as the semi-honest original versions and require the external verifier to be involved only when the client or server deviates from the protocol. Finally, we implement externally verified ORAM, along with an automated cryptocurrency contract to use as the external verifier.

  20. Relaxed memory models: an operational approach

    OpenAIRE

    Boudol , Gérard; Petri , Gustavo

    2009-01-01

    International audience; Memory models define an interface between programs written in some language and their implementation, determining which behaviour the memory (and thus a program) is allowed to have in a given model. A minimal guarantee memory models should provide to the programmer is that well-synchronized, that is, data-race free code has a standard semantics. Traditionally, memory models are defined axiomatically, setting constraints on the order in which memory operations are allow...

  1. Reasons for withdrawing belief in vivid autobiographical memories.

    Science.gov (United States)

    Scoboria, Alan; Boucher, Chantal; Mazzoni, Giuliana

    2015-01-01

    Previous studies have shown that many people hold personal memories for events that they no longer believe occurred. This study examines the reasons that people provide for choosing to reduce autobiographical belief in vividly recollected autobiographical memories. A body of non-believed memories provided by 374 individuals was reviewed to develop a qualitatively derived categorisation system. The final scheme consisted of 8 major categories (in descending order of mention): social feedback, event plausibility, alternative attributions, general memory beliefs, internal event features, consistency with external evidence, views of self/others, personal motivation and numerous sub-categories. Independent raters coded the reports and judged the primary reason that each person provided for withdrawing belief. The nature of each category, frequency of category endorsement, category overlap and phenomenological ratings are presented, following which links to related literature and implications are discussed. This study documents that a wide variety of recollective and non-recollective sources of information influence decision-making about the occurrence of autobiographical events.

  2. True photographs and false memories.

    Science.gov (United States)

    Lindsay, D Stephen; Hagen, Lisa; Read, J Don; Wade, Kimberley A; Garry, Maryanne

    2004-03-01

    Some trauma-memory-oriented psychotherapists advise clients to review old family photo albums to cue suspected "repressed" memories of childhood sexual abuse. Old photos might cue long-forgotten memories, but when combined with other suggestive influences they might also contribute to false memories. We asked 45 undergraduates to work at remembering three school-related childhood events (two true events provided by parents and one pseudoevent). By random assignment, 23 subjects were also given their school classes' group photos from the years of the to-be-recalled events as memory cues. As predicted, the rate of false-memory reports was dramatically higher in the photo condition than in the no-photo condition. Indeed, the rate of false-memory reports in the photo condition was substantially higher than the rate in any previously published study.

  3. Memory design

    DEFF Research Database (Denmark)

    Tanderup, Sisse

    by cultural forms, often specifically by the concept of memory in philosophy, sociology and psychology, while Danish design traditionally has been focusing on form and function with frequent references to the forms of nature. Alessi's motivation for investigating the concept of memory is that it adds......Mind and Matter - Nordik 2009 Conference for Art Historians Design Matters Contributed Memory design BACKGROUND My research concerns the use of memory categories in the designs by the companies Alessi and Georg Jensen. When Alessi's designers create their products, they are usually inspired...... a cultural dimension to the design objects, enabling the objects to make an identity-forming impact. Whether or not the concept of memory plays a significant role in Danish design has not yet been elucidated fully. TERMINOLOGY The concept of "memory design" refers to the idea that design carries...

  4. Disputed Memory

    DEFF Research Database (Denmark)

    , individual and political discourse and electronic social media. Analyzing memory disputes in various local, national and transnational contexts, the chapters demonstrate the political power and social impact of painful and disputed memories. The book brings new insights into current memory disputes...... in Central, Eastern and Southeastern Europe. It contributes to the understanding of processes of memory transmission and negotiation across borders and cultures in Europe, emphasizing the interconnectedness of memory with emotions, mediation and politics....... century in the region. Written by an international group of scholars from a diversity of disciplines, the chapters approach memory disputes in methodologically innovative ways, studying representations and negotiations of disputed pasts in different media, including monuments, museum exhibitions...

  5. Exploring memory hierarchy design with emerging memory technologies

    CERN Document Server

    Sun, Guangyu

    2014-01-01

    This book equips readers with tools for computer architecture of high performance, low power, and high reliability memory hierarchy in computer systems based on emerging memory technologies, such as STTRAM, PCM, FBDRAM, etc.  The techniques described offer advantages of high density, near-zero static power, and immunity to soft errors, which have the potential of overcoming the “memory wall.”  The authors discuss memory design from various perspectives: emerging memory technologies are employed in the memory hierarchy with novel architecture modification;  hybrid memory structure is introduced to leverage advantages from multiple memory technologies; an analytical model named “Moguls” is introduced to explore quantitatively the optimization design of a memory hierarchy; finally, the vulnerability of the CMPs to radiation-based soft errors is improved by replacing different levels of on-chip memory with STT-RAMs.   ·         Provides a holistic study of using emerging memory technologies i...

  6. About Sleep's Role in Memory

    Science.gov (United States)

    2013-01-01

    Over more than a century of research has established the fact that sleep benefits the retention of memory. In this review we aim to comprehensively cover the field of “sleep and memory” research by providing a historical perspective on concepts and a discussion of more recent key findings. Whereas initial theories posed a passive role for sleep enhancing memories by protecting them from interfering stimuli, current theories highlight an active role for sleep in which memories undergo a process of system consolidation during sleep. Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories. Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory. Ensuing REM sleep may stabilize transformed memories. While elaborated with respect to hippocampus-dependent memories, the concept of an active redistribution of memory representations from networks serving as temporary store into long-term stores might hold also for non-hippocampus-dependent memory, and even for nonneuronal, i.e., immunological memories, giving rise to the idea that the offline consolidation of memory during sleep represents a principle of long-term memory formation established in quite different physiological systems. PMID:23589831

  7. Maternal scaffolding in a disadvantaged global context: The influence of working memory and cognitive capacities.

    Science.gov (United States)

    Obradović, Jelena; Portilla, Ximena A; Tirado-Strayer, Nicole; Siyal, Saima; Rasheed, Muneera A; Yousafzai, Aisha K

    2017-03-01

    The current study focuses on maternal cognitive capacities as determinants of parenting in a highly disadvantaged global context, where children's experiences at home are often the 1st and only opportunity for learning and intellectual growth. In a large sample of 1,291 biological mothers of preschool-aged children in rural Pakistan, we examined the unique association of maternal working memory skills (independent of related cognitive capacities) with cognitively stimulating parenting behaviors. Path analysis revealed that directly assessed working memory, short-term memory, and verbal intelligence independently predicted greater levels of observed maternal scaffolding behaviors. Mothers from poorer families demonstrated lower levels of working memory, short-term memory, and verbal intelligence. However, mothers' participation in an early childhood parenting intervention that ended 2 years prior to this study contributed to greater levels of working memory skills and verbal intelligence. Further, all 3 domains of maternal cognitive capacity mediated the effect of family economic resources on maternal scaffolding, and verbal intelligence also mediated the effect of early parenting intervention exposure on maternal scaffolding. The study demonstrates the unique relevance of maternal working memory for scaffolding behaviors that required continuously monitoring the child's engagement, providing assistance, and minimizing external distractions. These results highlight the importance of directly targeting maternal cognitive capacities in poor women with little or no formal education, using a 2-generation intervention approach that includes activities known to promote parental executive functioning and literacy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Main Memory

    OpenAIRE

    Boncz, Peter; Liu, Lei; Özsu, M.

    2008-01-01

    htmlabstractPrimary storage, presently known as main memory, is the largest memory directly accessible to the CPU in the prevalent Von Neumann model and stores both data and instructions (program code). The CPU continuously reads instructions stored there and executes them. It is also called Random Access Memory (RAM), to indicate that load/store instructions can access data at any location at the same cost, is usually implemented using DRAM chips, which are connected to the CPU and other per...

  9. Next decade in external dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1988-01-01

    In recent years, a number of external dosimetry problems have been solved. However, changes in standards and legal concepts relating to the application of dosimetry results will require further enhancements in measurement techniques and philosophy in the next 10 y. The introduction of effective dose equivalent and the legal use of probability of causation will require that much greater attention be given to determination of weighted organ dose from external exposure. An imminent change--an increase in the fast neutron quality factor--will require a new round of technology development in a field that has just received a decade of close scrutiny. For the future, we must take advantage of developments in microelectronics. The use of random access memory (RAM) and metal-on-silicon (MOS) devices as detector elements, particularly for neutron dosimetry, has exciting possibilities that are just beginning to be explored. Advances in microcircuitry are leading, and will continue to lead, in the development of a new generation of small, rugged and smart radiation survey instruments that will make the most of detector data. It has become possible with very compact instruments to obtain energy spectra, linear-energy-transfer (LET) spectra, and quality factors in addition to the usual integrated dosimetric quantities: exposure, absorbed dose, and dose equivalent. These instruments will be reliable and easy to use. The user will be able to select the level of sophistication that is required for any specific application. Moreover, since the processing algorithms can be changed, changes in conversion factors can be accommodated with relative ease. During the next decade, the use of computers will continue to grow in value to the health physicist

  10. Iconic Memories Die a Sudden Death.

    Science.gov (United States)

    Pratte, Michael S

    2018-06-01

    Iconic memory is characterized by its large storage capacity and brief storage duration, whereas visual working memory is characterized by its small storage capacity. The limited information stored in working memory is often modeled as an all-or-none process in which studied information is either successfully stored or lost completely. This view raises a simple question: If almost all viewed information is stored in iconic memory, yet one second later most of it is completely absent from working memory, what happened to it? Here, I characterized how the precision and capacity of iconic memory changed over time and observed a clear dissociation: Iconic memory suffered from a complete loss of visual items, while the precision of items retained in memory was only marginally affected by the passage of time. These results provide new evidence for the discrete-capacity view of working memory and a new characterization of iconic memory decay.

  11. Near-memory data reorganization engine

    Science.gov (United States)

    Gokhale, Maya; Lloyd, G. Scott

    2018-05-08

    A memory subsystem package is provided that has processing logic for data reorganization within the memory subsystem package. The processing logic is adapted to reorganize data stored within the memory subsystem package. In some embodiments, the memory subsystem package includes memory units, a memory interconnect, and a data reorganization engine ("DRE"). The data reorganization engine includes a stream interconnect and DRE units including a control processor and a load-store unit. The control processor is adapted to execute instructions to control a data reorganization. The load-store unit is adapted to process data move commands received from the control processor via the stream interconnect for loading data from a load memory address of a memory unit and storing data to a store memory address of a memory unit.

  12. Topological Schemas of Memory Spaces

    Science.gov (United States)

    Babichev, Andrey; Dabaghian, Yuri A.

    2018-01-01

    Hippocampal cognitive map—a neuronal representation of the spatial environment—is widely discussed in the computational neuroscience literature for decades. However, more recent studies point out that hippocampus plays a major role in producing yet another cognitive framework—the memory space—that incorporates not only spatial, but also non-spatial memories. Unlike the cognitive maps, the memory spaces, broadly understood as “networks of interconnections among the representations of events,” have not yet been studied from a theoretical perspective. Here we propose a mathematical approach that allows modeling memory spaces constructively, as epiphenomena of neuronal spiking activity and thus to interlink several important notions of cognitive neurophysiology. First, we suggest that memory spaces have a topological nature—a hypothesis that allows treating both spatial and non-spatial aspects of hippocampal function on equal footing. We then model the hippocampal memory spaces in different environments and demonstrate that the resulting constructions naturally incorporate the corresponding cognitive maps and provide a wider context for interpreting spatial information. Lastly, we propose a formal description of the memory consolidation process that connects memory spaces to the Morris' cognitive schemas-heuristic representations of the acquired memories, used to explain the dynamics of learning and memory consolidation in a given environment. The proposed approach allows evaluating these constructs as the most compact representations of the memory space's structure. PMID:29740306

  13. Topological Schemas of Memory Spaces

    Directory of Open Access Journals (Sweden)

    Andrey Babichev

    2018-04-01

    Full Text Available Hippocampal cognitive map—a neuronal representation of the spatial environment—is widely discussed in the computational neuroscience literature for decades. However, more recent studies point out that hippocampus plays a major role in producing yet another cognitive framework—the memory space—that incorporates not only spatial, but also non-spatial memories. Unlike the cognitive maps, the memory spaces, broadly understood as “networks of interconnections among the representations of events,” have not yet been studied from a theoretical perspective. Here we propose a mathematical approach that allows modeling memory spaces constructively, as epiphenomena of neuronal spiking activity and thus to interlink several important notions of cognitive neurophysiology. First, we suggest that memory spaces have a topological nature—a hypothesis that allows treating both spatial and non-spatial aspects of hippocampal function on equal footing. We then model the hippocampal memory spaces in different environments and demonstrate that the resulting constructions naturally incorporate the corresponding cognitive maps and provide a wider context for interpreting spatial information. Lastly, we propose a formal description of the memory consolidation process that connects memory spaces to the Morris' cognitive schemas-heuristic representations of the acquired memories, used to explain the dynamics of learning and memory consolidation in a given environment. The proposed approach allows evaluating these constructs as the most compact representations of the memory space's structure.

  14. Firm Search for External Knowledge

    DEFF Research Database (Denmark)

    Sofka, Wolfgang; Grimpe, Christoph

    2012-01-01

    ignored the institutional context that provides or denies access to external knowledge at the country level. Combining institutional and knowledge search theory, we suggest that the market orientation of the institutional environment and the magnitude of institutional change influence when firms begin......The innovation performance of modern firms is increasingly determined by their ability to search and absorb external knowledge. However, after a certain threshold firms "oversearch" their environment and innovation performance declines. In this paper, we argue that prior literature has largely...... to experience the negative performance effects of oversearch. Based on a comprehensive sample of almost 8,000 firms from ten European countries, we find that institutions matter considerably for firms' search activity. Higher market orientation of institutions increases the effectiveness of firms' search...

  15. MGR External Events Hazards Analysis

    International Nuclear Information System (INIS)

    Booth, L.

    1999-01-01

    The purpose and objective of this analysis is to apply an external events Hazards Analysis (HA) to the License Application Design Selection Enhanced Design Alternative 11 [(LADS EDA II design (Reference 8.32))]. The output of the HA is called a Hazards List (HL). This analysis supersedes the external hazards portion of Rev. 00 of the PHA (Reference 8.1). The PHA for internal events will also be updated to the LADS EDA II design but under a separate analysis. Like the PHA methodology, the HA methodology provides a systematic method to identify potential hazards during the 100-year Monitored Geologic Repository (MGR) operating period updated to reflect the EDA II design. The resulting events on the HL are candidates that may have potential radiological consequences as determined during Design Basis Events (DBEs) analyses. Therefore, the HL that results from this analysis will undergo further screening and analysis based on the criteria that apply during the performance of DBE analyses

  16. Internal and External Readings of Same

    DEFF Research Database (Denmark)

    Hardt, Daniel

    2016-01-01

    Same is an anaphoric element that performs a comparison, which can either be external or internal to a sentence. Hardt and Mikkelsen (2015) show that same, unlike other anaphoric expressions, imposes a parallelism constraint, and they present three types of examples showing that same...... is infelicitous in the absence of parallelism. Hardt and Mikkelsen propose an account that applies uniformly to internal and external readings; however, the evidence they present largely targets external readings – they don’t offer empirical evidence that clearly supports the uniform approach. Furthermore, Barker...... (2007) argues that internal readings must be treated differently than external readings. In this paper, I show that the parallelism effects observed by Hardt and Mikkelsen in fact apply to internal readings as well. This provides support for a uniform treatment of internal and external readings of same...

  17. Novel memory architecture for video signal processor

    Science.gov (United States)

    Hung, Jen-Sheng; Lin, Chia-Hsing; Jen, Chein-Wei

    1993-11-01

    An on-chip memory architecture for video signal processor (VSP) is proposed. This memory structure is a two-level design for the different data locality in video applications. The upper level--Memory A provides enough storage capacity to reduce the impact on the limitation of chip I/O bandwidth, and the lower level--Memory B provides enough data parallelism and flexibility to meet the requirements of multiple reconfigurable pipeline function units in a single VSP chip. The needed memory size is decided by the memory usage analysis for video algorithms and the number of function units. Both levels of memory adopted a dual-port memory scheme to sustain the simultaneous read and write operations. Especially, Memory B uses multiple one-read-one-write memory banks to emulate the real multiport memory. Therefore, one can change the configuration of Memory B to several sets of memories with variable read/write ports by adjusting the bus switches. Then the numbers of read ports and write ports in proposed memory can meet requirement of data flow patterns in different video coding algorithms. We have finished the design of a prototype memory design using 1.2- micrometers SPDM SRAM technology and will fabricated it through TSMC, in Taiwan.

  18. Malignant external otitis

    International Nuclear Information System (INIS)

    Dupuch, K.M.; Iryboz, T.; Firat, M.; Levy, C.; Tubiana, J.M.

    1991-01-01

    This paper illustrates the value of CT and MR in early diagnosis and spread of malignant external otitis. The authors retrospectively analyzed 15 patients with proved malignant external otitis examined with postcontrast high-resolution CT (15/15) and MR (6/15) (T1- and T2-weighting). Gallium studies were done in 6/15 patients. Early diagnosis was made when CT demonstrated a soft-tissue mass of the external auditory canal associated with scattered zones of cortical bone erosions (13/15). Spread of the disease was better delineated by MR than CT, especially skull base extension (6/15). Temporomandibular joint involvement with extension into parotid or/and masticator spaces 6/15 was as well detected with CT as with MR. If CT remains the first and best procedure for diagnosis, MR - despite its cost - appears a good procedure to depict exact anatomic spread, allowing therapeutic management

  19. Productivity Change and Externalities

    DEFF Research Database (Denmark)

    Kravtsova, Victoria

    2014-01-01

    This paper contributes to the analysis of the impact of externalities on the host country's total factor productivity by taking into account different dimensions of spillover effects. Namely, engagement in exporting and foreign ownership is generally perceived as being beneficial to individual...... firms and the economy as a whole. The approach used in the current research accounts for different internal as well as external factors that individual firms face and evaluates the effect on changes in productivity, technology as well as the efficiency of domestic firms. The empirical analysis focuses...... on Hungary. While the country leads the group of post-socialist countries in the amount of attracted foreign direct investments (FDI) the effect of this policy on the economy remains unclear. The research finds that different externalities play a different role in productivity, technological and efficiency...

  20. Externality or sustainability economics?

    International Nuclear Information System (INIS)

    Bergh, Jeroen C.J.M. van den

    2010-01-01

    In an effort to develop 'sustainability economics' Baumgaertner and Quaas (2010) neglect the central concept of environmental economics-'environmental externality'. This note proposes a possible connection between the concepts of environmental externality and sustainability. In addition, attention is asked for other aspects of 'sustainability economics', namely the distinction weak/strong sustainability, spatial sustainability and sustainable trade, distinctive sustainability policy, and the ideas of early 'sustainability economists'. I argue that both sustainability and externalities reflect a systems perspective and propose that effective sustainability solutions require that more attention is given to system feedbacks, notably other-regarding preferences and social interactions, and energy and environmental rebound. The case of climate change and policy is used to illustrate particular statements. As a conclusion, a list of 20 insights and suggestions for research is offered. (author)

  1. Metasurface external cavity laser

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Luyao, E-mail: luyaoxu.ee@ucla.edu; Curwen, Christopher A.; Williams, Benjamin S. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute, University of California, Los Angeles, California 90095 (United States); Hon, Philip W. C.; Itoh, Tatsuo [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Chen, Qi-Sheng [Northrop Grumman Aerospace Systems, Redondo Beach, California 90278 (United States)

    2015-11-30

    A vertical-external-cavity surface-emitting-laser is demonstrated in the terahertz range, which is based upon an amplifying metasurface reflector composed of a sub-wavelength array of antenna-coupled quantum-cascade sub-cavities. Lasing is possible when the metasurface reflector is placed into a low-loss external cavity such that the external cavity—not the sub-cavities—determines the beam properties. A near-Gaussian beam of 4.3° × 5.1° divergence is observed and an output power level >5 mW is achieved. The polarized response of the metasurface allows the use of a wire-grid polarizer as an output coupler that is continuously tunable.

  2. Collaging Memories

    Science.gov (United States)

    Wallach, Michele

    2011-01-01

    Even middle school students can have memories of their childhoods, of an earlier time. The art of Romare Bearden and the writings of Paul Auster can be used to introduce ideas about time and memory to students and inspire works of their own. Bearden is an exceptional role model for young artists, not only because of his astounding art, but also…

  3. Memory Magic.

    Science.gov (United States)

    Hartman, Thomas G.; Nowak, Norman

    This paper outlines several "tricks" that aid students in improving their memories. The distinctions between operational and figural thought processes are noted. Operational memory is described as something that allows adults to make generalizations about numbers and the rules by which they may be combined, thus leading to easier memorization.…

  4. Memory loss

    Science.gov (United States)

    ... barbiturates or ( hypnotics ) ECT (electroconvulsive therapy) (most often short-term memory loss) Epilepsy that is not well controlled Illness that ... appointment. Medical history questions may include: Type of memory loss, such as short-term or long-term Time pattern, such as how ...

  5. Flavor Memory

    NARCIS (Netherlands)

    Mojet, Jos; Köster, Ep

    2016-01-01

    Odor, taste, texture, temperature, and pain all contribute to the perception and memory of food flavor. Flavor memory is also strongly linked to the situational aspects of previous encounters with the flavor, but does not depend on the precise recollection of its sensory features as in vision and

  6. Main Memory

    NARCIS (Netherlands)

    P.A. Boncz (Peter); L. Liu (Lei); M. Tamer Özsu

    2008-01-01

    htmlabstractPrimary storage, presently known as main memory, is the largest memory directly accessible to the CPU in the prevalent Von Neumann model and stores both data and instructions (program code). The CPU continuously reads instructions stored there and executes them. It is also called Random

  7. The External Mind

    DEFF Research Database (Denmark)

    , Extended Mind and Distributed Cognition by Claudio Paolucci pp. 69-96 The Social Horizon of Embodied Language and Material Symbols by Riccardo Fusaroli pp. 97-123 Semiotics and Theories of Situated/Distributed Action and Cognition: a Dialogue and Many Intersections by Tommaso Granelli pp. 125-167 Building......The External Mind: an Introduction by Riccardo Fusaroli, Claudio Paolucci pp. 3-31 The sign of the Hand: Symbolic Practices and the Extended Mind by Massimiliano Cappuccio, Michael Wheeler pp. 33-55 The Overextended Mind by Shaun Gallagher pp. 57-68 The "External Mind": Semiotics, Pragmatism...

  8. Working memory and simultaneous interpreting

    OpenAIRE

    Timarova, Sarka

    2009-01-01

    Working memory is a cognitive construct underlying a number of abilities, and it has been hypothesised for many years that it is crucial for interpreting. A number of studies have been conducted with the aim to support this hypothesis, but research has not yielded convincing results. Most researchers focused on studying working memory differences between interpreters and non-interpreters with the rationale that differences in working memory between the two groups would provide evidence of wor...

  9. The Benefit of Attention-to-Memory Depends on the Interplay of Memory Capacity and Memory Load

    Science.gov (United States)

    Lim, Sung-Joo; Wöstmann, Malte; Geweke, Frederik; Obleser, Jonas

    2018-01-01

    Humans can be cued to attend to an item in memory, which facilitates and enhances the perceptual precision in recalling this item. Here, we demonstrate that this facilitating effect of attention-to-memory hinges on the overall degree of memory load. The benefit an individual draws from attention-to-memory depends on her overall working memory performance, measured as sensitivity (d′) in a retroactive cue (retro-cue) pitch discrimination task. While listeners maintained 2, 4, or 6 auditory syllables in memory, we provided valid or neutral retro-cues to direct listeners’ attention to one, to-be-probed syllable in memory. Participants’ overall memory performance (i.e., perceptual sensitivity d′) was relatively unaffected by the presence of valid retro-cues across memory loads. However, a more fine-grained analysis using psychophysical modeling shows that valid retro-cues elicited faster pitch-change judgments and improved perceptual precision. Importantly, as memory load increased, listeners’ overall working memory performance correlated with inter-individual differences in the degree to which precision improved (r = 0.39, p = 0.029). Under high load, individuals with low working memory profited least from attention-to-memory. Our results demonstrate that retrospective attention enhances perceptual precision of attended items in memory but listeners’ optimal use of informative cues depends on their overall memory abilities. PMID:29520246

  10. The Benefit of Attention-to-Memory Depends on the Interplay of Memory Capacity and Memory Load

    Directory of Open Access Journals (Sweden)

    Sung-Joo Lim

    2018-02-01

    Full Text Available Humans can be cued to attend to an item in memory, which facilitates and enhances the perceptual precision in recalling this item. Here, we demonstrate that this facilitating effect of attention-to-memory hinges on the overall degree of memory load. The benefit an individual draws from attention-to-memory depends on her overall working memory performance, measured as sensitivity (d′ in a retroactive cue (retro-cue pitch discrimination task. While listeners maintained 2, 4, or 6 auditory syllables in memory, we provided valid or neutral retro-cues to direct listeners’ attention to one, to-be-probed syllable in memory. Participants’ overall memory performance (i.e., perceptual sensitivity d′ was relatively unaffected by the presence of valid retro-cues across memory loads. However, a more fine-grained analysis using psychophysical modeling shows that valid retro-cues elicited faster pitch-change judgments and improved perceptual precision. Importantly, as memory load increased, listeners’ overall working memory performance correlated with inter-individual differences in the degree to which precision improved (r = 0.39, p = 0.029. Under high load, individuals with low working memory profited least from attention-to-memory. Our results demonstrate that retrospective attention enhances perceptual precision of attended items in memory but listeners’ optimal use of informative cues depends on their overall memory abilities.

  11. Externalities - an analysis using the EU ExternE-results

    International Nuclear Information System (INIS)

    2003-10-01

    The EU project ExternE quantified the externalities for the different energy technologies. In this work, the ExternE results are used in a MARKAL-analysis for the Nordic countries. The analysis does not go into detail, but gives some interesting indications: The external costs are not fully covered in the Nordic energy systems, the present taxes and charges are not high enough. The emissions from the energy systems would be strongly reduced, if taxes/environmental charges were set at the level ExternE calculate. The emissions from power production would be reduced most. Renewable energy sources and natural gas dominate the energy systems in the ExternE case

  12. Is hepatitis B vaccination performed at infant and adolescent age able to provide long-term immunological memory? An observational study on healthcare students and workers in Florence, Italy.

    Science.gov (United States)

    Bini, Costanza; Grazzini, Maddalena; Chellini, Martina; Mucci, Nicola; Arcangeli, Giulio; Tiscione, Emilia; Bonanni, Paolo

    2018-02-01

    Universal vaccination programmes against Hepatitis B Virus (HBV) have significantly reduced the burden of the disease; nevertheless, HBV infection remains a relevant issue for high-risk subjects, such as healthcare workers (HCWs), who may potentially be exposed to blood or body fluids. Our study evaluates the long-term duration of the immunological memory of HBV vaccination 11-23 years after primary immunization by examining the response to booster doses in HCWs and students of health disciplines at Careggi Teaching Hospital in Florence (Italy). All participants (n = 2,203) had received a complete HBV immunization course in infancy or adolescence. Blood samples were collected to measure antibody levels against the HBV surface antigen (anti-HBs); an anti-HBs titre long-term anti-HBs titres compared to those in case of vaccination performed during adolescence (titre long incubation period of the disease allows the activation of immunologic memory mechanisms, which is also true in case of low anti-HBs level. In conclusion HCWs still represent a high-risk category; it is therefore, necessary to increase efforts to protect and vaccinate these subjects.

  13. External costs of electricity

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2005-01-01

    This article presents a synthesis of the ExternE project (External costs of Energy) of the European community about the external costs of power generation. Pollution impacts are calculated using an 'impact pathways' analysis, i.e. an analysis of the emission - dispersion - dose-response function - cost evaluation chain. Results are presented for different fuel cycles (with several technological variants) with their confidence intervals. The environmental impact costs are particularly high for coal: for instance, in France, for coal-fired power plants it is of the same order as the electricity retail price. For natural gas, this cost is about a third of the one for coal. On the contrary, the environmental impact costs for nuclear and renewable energies are low, typically of few per cent of the electricity price. The main part of these costs corresponds to the sanitary impacts, in particular the untimely mortality. In order to avoid any controversy about the cost evaluation of mortality, the reduction of the expectation of life due to the different fuel cycles is also indicated and the risks linked with nuclear energy are presented using several comparisons. (J.S.)

  14. On parabolic external maps

    DEFF Research Database (Denmark)

    Lomonaco, Luna; Petersen, Carsten Lunde; Shen, Weixiao

    2017-01-01

    We prove that any C1+BV degree d ≥ 2 circle covering h having all periodic orbits weakly expanding, is conjugate by a C1+BV diffeomorphism to a metrically expanding map. We use this to connect the space of parabolic external maps (coming from the theory of parabolic-like maps) to metrically expan...

  15. Stochastic Control - External Models

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    2005-01-01

    This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...

  16. Susceptibility of memory consolidation during lapses in recall.

    Science.gov (United States)

    Marra, Vincenzo; O'Shea, Michael; Benjamin, Paul R; Kemenes, Ildikó

    2013-01-01

    Memories that can be recalled several hours after learning may paradoxically become inaccessible for brief periods after their formation. This raises major questions about the function of these early memory lapses in the structure of memory consolidation. These questions are difficult to investigate because of the lack of information on the precise timing of lapses. However, the use of a single-trial conditioning paradigm in Lymnaea solves this problem. Here we use electrophysiological and behavioural experiments to reveal lapses in memory recall at 30 min and 2 h post conditioning. We show that only during these lapses is consolidation of long-term memory susceptible to interruption by external disturbance. These shared time points of memory lapse and susceptibility correspond to transitions between different phases of memory that have different molecular requirements. We propose that during periods of molecular transition memory recall is weakened, allowing novel sensory cues to block the consolidation of long-term memory.

  17. Non-Hebbian learning implementation in light-controlled resistive memory devices.

    Science.gov (United States)

    Ungureanu, Mariana; Stoliar, Pablo; Llopis, Roger; Casanova, Fèlix; Hueso, Luis E

    2012-01-01

    Non-Hebbian learning is often encountered in different bio-organisms. In these processes, the strength of a synapse connecting two neurons is controlled not only by the signals exchanged between the neurons, but also by an additional factor external to the synaptic structure. Here we show the implementation of non-Hebbian learning in a single solid-state resistive memory device. The output of our device is controlled not only by the applied voltages, but also by the illumination conditions under which it operates. We demonstrate that our metal/oxide/semiconductor device learns more efficiently at higher applied voltages but also when light, an external parameter, is present during the information writing steps. Conversely, memory erasing is more efficiently at higher applied voltages and in the dark. Translating neuronal activity into simple solid-state devices could provide a deeper understanding of complex brain processes and give insight into non-binary computing possibilities.

  18. PIYAS-Proceeding to Intelligent Service Oriented Memory Allocation for Flash Based Data Centric Sensor Devices in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sanam Shahla Rizvi

    2009-12-01

    Full Text Available Flash memory has become a more widespread storage medium for modern wireless devices because of its effective characteristics like non-volatility, small size, light weight, fast access speed, shock resistance, high reliability and low power consumption. Sensor nodes are highly resource constrained in terms of limited processing speed, runtime memory, persistent storage, communication bandwidth and finite energy. Therefore, for wireless sensor networks supporting sense, store, merge and send schemes, an efficient and reliable file system is highly required with consideration of sensor node constraints. In this paper, we propose a novel log structured external NAND flash memory based file system, called Proceeding to Intelligent service oriented memorY Allocation for flash based data centric Sensor devices in wireless sensor networks (PIYAS. This is the extended version of our previously proposed PIYA [1]. The main goals of the PIYAS scheme are to achieve instant mounting and reduced SRAM space by keeping memory mapping information to a very low size of and to provide high query response throughput by allocation of memory to the sensor data by network business rules. The scheme intelligently samples and stores the raw data and provides high in-network data availability by keeping the aggregate data for a longer period of time than any other scheme has done before. We propose effective garbage collection and wear-leveling schemes as well. The experimental results show that PIYAS is an optimized memory management scheme allowing high performance for wireless sensor networks.

  19. PIYAS-proceeding to intelligent service oriented memory allocation for flash based data centric sensor devices in wireless sensor networks.

    Science.gov (United States)

    Rizvi, Sanam Shahla; Chung, Tae-Sun

    2010-01-01

    Flash memory has become a more widespread storage medium for modern wireless devices because of its effective characteristics like non-volatility, small size, light weight, fast access speed, shock resistance, high reliability and low power consumption. Sensor nodes are highly resource constrained in terms of limited processing speed, runtime memory, persistent storage, communication bandwidth and finite energy. Therefore, for wireless sensor networks supporting sense, store, merge and send schemes, an efficient and reliable file system is highly required with consideration of sensor node constraints. In this paper, we propose a novel log structured external NAND flash memory based file system, called Proceeding to Intelligent service oriented memorY Allocation for flash based data centric Sensor devices in wireless sensor networks (PIYAS). This is the extended version of our previously proposed PIYA [1]. The main goals of the PIYAS scheme are to achieve instant mounting and reduced SRAM space by keeping memory mapping information to a very low size of and to provide high query response throughput by allocation of memory to the sensor data by network business rules. The scheme intelligently samples and stores the raw data and provides high in-network data availability by keeping the aggregate data for a longer period of time than any other scheme has done before. We propose effective garbage collection and wear-leveling schemes as well. The experimental results show that PIYAS is an optimized memory management scheme allowing high performance for wireless sensor networks.

  20. Sleep loss produces false memories.

    Directory of Open Access Journals (Sweden)

    Susanne Diekelmann

    Full Text Available People sometimes claim with high confidence to remember events that in fact never happened, typically due to strong semantic associations with actually encoded events. Sleep is known to provide optimal neurobiological conditions for consolidation of memories for long-term storage, whereas sleep deprivation acutely impairs retrieval of stored memories. Here, focusing on the role of sleep-related memory processes, we tested whether false memories can be created (a as enduring memory representations due to a consolidation-associated reorganization of new memory representations during post-learning sleep and/or (b as an acute retrieval-related phenomenon induced by sleep deprivation at memory testing. According to the Deese, Roediger, McDermott (DRM false memory paradigm, subjects learned lists of semantically associated words (e.g., "night", "dark", "coal",..., lacking the strongest common associate or theme word (here: "black". Subjects either slept or stayed awake immediately after learning, and they were either sleep deprived or not at recognition testing 9, 33, or 44 hours after learning. Sleep deprivation at retrieval, but not sleep following learning, critically enhanced false memories of theme words. This effect was abolished by caffeine administration prior to retrieval, indicating that adenosinergic mechanisms can contribute to the generation of false memories associated with sleep loss.

  1. Mechanisms of Memory Enhancement

    Science.gov (United States)

    Stern, Sarah A.

    2012-01-01

    The ongoing quest for memory enhancement is one that grows necessary as the global population increasingly ages. The extraordinary progress that has been made in the past few decades elucidating the underlying mechanisms of how long-term memories are formed has provided insight into how memories might also be enhanced. Capitalizing on this knowledge, it has been postulated that targeting many of the same mechanisms, including CREB activation, AMPA/NMDA receptor trafficking, neuromodulation (e.g. via dopamine, adrenaline, cortisol or acetylcholine) and metabolic processes (e.g. via glucose and insulin) may all lead to the enhancement of memory. These and other mechanisms and/or approaches have been tested via genetic or pharmacological methods in animal models, and several have been investigated in humans as well. In addition, a number of behavioral methods, including exercise and reconsolidation, may also serve to strengthen and enhance memories. By capitalizing on this knowledge and continuing to investigate these promising avenues, memory enhancement may indeed be achieved in the future. PMID:23151999

  2. Immune memory in invertebrates.

    Science.gov (United States)

    Milutinović, Barbara; Kurtz, Joachim

    2016-08-01

    Evidence for innate immune memory (or 'priming') in invertebrates has been accumulating over the last years. We here provide an in-depth review of the current state of evidence for immune memory in invertebrates, and in particular take a phylogenetic viewpoint. Invertebrates are a very heterogeneous group of animals and accordingly, evidence for the phenomenon of immune memory as well as the hypothesized molecular underpinnings differ largely for the diverse invertebrate taxa. The majority of research currently focuses on Arthropods, while evidence from many other groups of invertebrates is fragmentary or even lacking. We here concentrate on immune memory that is induced by pathogenic challenges, but also extent our view to a non-pathogenic context, i.e. allograft rejection, which can also show forms of memory and can inform us about general principles of specific self-nonself recognition. We discuss definitions of immune memory and a number of relevant aspects such as the type of antigens used, the route of exposure, and the kinetics of reactions following priming. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. False memories and confabulation.

    Science.gov (United States)

    Johnson, M K; Raye, C L

    1998-04-01

    Memory distortions range from the benign (thinking you mailed a check that you only thought about mailing), to the serious (confusing what you heard after a crime with what you actually saw), to the fantastic (claiming you piloted a spaceship). We review theoretical ideas and empirical evidence about the source monitoring processes underlying both true and false memories. Neuropsychological studies show that certain forms of brain damage (such as combined frontal and medial-temporal lesions) might result in profound source confusions, called confabulations. Neuroimaging techniques provide new evidence regarding more specific links between underlying brain mechanisms and the normal cognitive processes involved in evaluating memories. One hypothesis is that the right prefrontal cortex (PFC) subserves heuristic judgments based on easily assessed qualities (such as familiarity or perceptual detail) and the left PFC (or the right and left PFC together) subserves more systematic judgments requiring more careful analysis of memorial qualities or retrieval and evaluation of additional supporting or disconfirming information. Such heuristic and systematic processes can be disrupted not only by brain damage but also, for example, by hypnosis, social demands and motivational factors, suggesting caution in the methods used by `memory exploring' professions (therapists, police officers, lawyers, etc.) in order to avoid inducing false memories.

  4. Magnetic vortex racetrack memory

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Liwei D.; Jin, Yongmei M., E-mail: ymjin@mtu.edu

    2017-02-01

    We report a new type of racetrack memory based on current-controlled movement of magnetic vortices in magnetic nanowires with rectangular cross-section and weak perpendicular anisotropy. Data are stored through the core polarity of vortices and each vortex carries a data bit. Besides high density, non-volatility, fast data access, and low power as offered by domain wall racetrack memory, magnetic vortex racetrack memory has additional advantages of no need for constrictions to define data bits, changeable information density, adjustable current magnitude for data propagation, and versatile means of ultrafast vortex core switching. By using micromagnetic simulations, current-controlled motion of magnetic vortices in cobalt nanowire is demonstrated for racetrack memory applications. - Highlights: • Advance fundamental knowledge of current-driven magnetic vortex phenomena. • Report appealing new magnetic racetrack memory based on current-controlled magnetic vortices in nanowires. • Provide a novel approach to adjust current magnitude for data propagation. • Overcome the limitations of domain wall racetrack memory.

  5. Dreaming and offline memory consolidation.

    Science.gov (United States)

    Wamsley, Erin J

    2014-03-01

    Converging evidence suggests that dreaming is influenced by the consolidation of memory during sleep. Following encoding, recently formed memory traces are gradually stabilized and reorganized into a more permanent form of long-term storage. Sleep provides an optimal neurophysiological state to facilitate this process, allowing memory networks to be repeatedly reactivated in the absence of new sensory input. The process of memory reactivation and consolidation in the sleeping brain appears to influence conscious experience during sleep, contributing to dream content recalled on awakening. This article outlines several lines of evidence in support of this hypothesis, and responds to some common objections.

  6. Random photonic crystal optical memory

    International Nuclear Information System (INIS)

    Wirth Lima Jr, A; Sombra, A S B

    2012-01-01

    Currently, optical cross-connects working on wavelength division multiplexing systems are based on optical fiber delay lines buffering. We designed and analyzed a novel photonic crystal optical memory, which replaces the fiber delay lines of the current optical cross-connect buffer. Optical buffering systems based on random photonic crystal optical memory have similar behavior to the electronic buffering systems based on electronic RAM memory. In this paper, we show that OXCs working with optical buffering based on random photonic crystal optical memories provides better performance than the current optical cross-connects. (paper)

  7. Memory Reconsolidation.

    Science.gov (United States)

    Haubrich, Josue; Nader, Karim

    2018-01-01

    Scientific advances in the last decades uncovered that memory is not a stable, fixed entity. Apparently stable memories may become transiently labile and susceptible to modifications when retrieved due to the process of reconsolidation. Here, we review the initial evidence and the logic on which reconsolidation theory is based, the wide range of conditions in which it has been reported and recent findings further revealing the fascinating nature of this process. Special focus is given to conceptual issues of when and why reconsolidation happen and its possible outcomes. Last, we discuss the potential clinical implications of memory modifications by reconsolidation.

  8. Matchings with Externalities and Attitudes

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal

    2013-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas ...... where agents take different attitudes when reasoning about the actions of others. In particular, we study optimistic, neutral and pessimistic attitudes and provide both computational hardness results and polynomial-time algorithms for computing stable outcomes....

  9. Nuclear energy and external constraints

    International Nuclear Information System (INIS)

    Lattes, R.; Thiriet, L.

    1983-01-01

    The structural factors of this crisis probably predominate over factors arising out the economic situation, even if explanations vary in this respect. In this article devoted to nuclear energy, a possible means of Loosering external constraints the current international economic environment is firstly outlined; the context in which the policies of industrialized countries, and therefore that of France, must be developed. An examination of the possible role of energy policies in general and nuclear policies in particular as an instrument of economic policy in providing a partial solution to this crisis, will then enable to quantitatively evaluate the effects of such policies at a national level [fr

  10. Singulus Technology公司准备在Memory-Tech公司运行其的全套HD DVD-ROM生产设备%SINGULUS TECHNOLOGIES to get ready for providing complete HD DVD-ROM Disc Production System working together with Memory-Tech

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    2004年12月27日,处于领导地位的光盘复制生产设备整合供应商Singulus Technology公司宣布其将在日本最大的媒体生产企业Memory-Tech公司运行其的HD DVD-ROM生产线。

  11. Deciphering Neural Codes of Memory during Sleep

    Science.gov (United States)

    Chen, Zhe; Wilson, Matthew A.

    2017-01-01

    Memories of experiences are stored in the cerebral cortex. Sleep is critical for consolidating hippocampal memory of wake experiences into the neocortex. Understanding representations of neural codes of hippocampal-neocortical networks during sleep would reveal important circuit mechanisms on memory consolidation, and provide novel insights into memory and dreams. Although sleep-associated ensemble spike activity has been investigated, identifying the content of memory in sleep remains challenging. Here, we revisit important experimental findings on sleep-associated memory (i.e., neural activity patterns in sleep that reflect memory processing) and review computational approaches for analyzing sleep-associated neural codes (SANC). We focus on two analysis paradigms for sleep-associated memory, and propose a new unsupervised learning framework (“memory first, meaning later”) for unbiased assessment of SANC. PMID:28390699

  12. The neurobiology of the human memory.

    Science.gov (United States)

    Fietta, Pierluigi; Fietta, Pieranna

    2011-01-01

    Memory can be defined as the ability to acquire, process, store, and retrieve information. Memory is indispensable for learning, adaptation, and survival of every living organism. In humans, the remembering process has acquired great flexibility and complexity, reaching close links with other mental functions, such as thinking and emotions. Changes in synaptic connectivity and interactions among multiple neural networks provide the neurobiological substrates for memory encoding, retention, and consolidation. Memory may be categorized as short-term and long-term memory (according to the storage temporal duration), as implicit and explicit memory (with respect to the consciousness of remembering), as declarative (knowing that [fact]) and procedural (knowing how [skill]) memory, or as sensory (echoic, iconic and haptil), semantic, and episodic memory (according to the various remembering domains). Significant advances have been obtained in understanding memory neurobiology, but much remains to be learned in its cognitive, psychological, and phenomenological aspects.

  13. Modeling Implicit and Explicit Memory.

    NARCIS (Netherlands)

    Raaijmakers, J.G.W.; Ohta, N.; Izawa, C.

    2005-01-01

    Mathematical models of memory are useful for describing basic processes of memory in a way that enables generalization across a number of experimental paradigms. Models that have these characteristics do not just engage in empirical curve-fitting, but may also provide explanations for puzzling

  14. Dual Coding and Bilingual Memory.

    Science.gov (United States)

    Paivio, Allan; Lambert, Wallace

    1981-01-01

    Describes study which tested a dual coding approach to bilingual memory using tasks that permit comparison of the effects of bilingual encoding with verbal-nonverbal dual encoding items. Results provide strong support for a version of the independent or separate stories view of bilingual memory. (Author/BK)

  15. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summarised...

  16. Forced to remember: when memory is biased by salient information.

    Science.gov (United States)

    Santangelo, Valerio

    2015-04-15

    The last decades have seen a rapid growing in the attempt to understand the key factors involved in the internal memory representation of the external world. Visual salience have been found to provide a major contribution in predicting the probability for an item/object embedded in a complex setting (i.e., a natural scene) to be encoded and then remembered later on. Here I review the existing literature highlighting the impact of perceptual- (based on low-level sensory features) and semantics-related salience (based on high-level knowledge) on short-term memory representation, along with the neural mechanisms underpinning the interplay between these factors. The available evidence reveal that both perceptual- and semantics-related factors affect attention selection mechanisms during the encoding of natural scenes. Biasing internal memory representation, both perceptual and semantics factors increase the probability to remember high- to the detriment of low-saliency items. The available evidence also highlight an interplay between these factors, with a reduced impact of perceptual-related salience in biasing memory representation as a function of the increasing availability of semantics-related salient information. The neural mechanisms underpinning this interplay involve the activation of different portions of the frontoparietal attention control network. Ventral regions support the assignment of selection/encoding priorities based on high-level semantics, while the involvement of dorsal regions reflects priorities assignment based on low-level sensory features. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Checklists for external validity

    DEFF Research Database (Denmark)

    Dyrvig, Anne-Kirstine; Kidholm, Kristian; Gerke, Oke

    2014-01-01

    to an implementation setting. In this paper, currently available checklists on external validity are identified, assessed and used as a basis for proposing a new improved instrument. METHOD: A systematic literature review was carried out in Pubmed, Embase and Cinahl on English-language papers without time restrictions....... The retrieved checklist items were assessed for (i) the methodology used in primary literature, justifying inclusion of each item; and (ii) the number of times each item appeared in checklists. RESULTS: Fifteen papers were identified, presenting a total of 21 checklists for external validity, yielding a total...... of 38 checklist items. Empirical support was considered the most valid methodology for item inclusion. Assessment of methodological justification showed that none of the items were supported empirically. Other kinds of literature justified the inclusion of 22 of the items, and 17 items were included...

  18. Multiferroic Memories

    Directory of Open Access Journals (Sweden)

    Amritendu Roy

    2012-01-01

    Full Text Available Multiferroism implies simultaneous presence of more than one ferroic characteristics such as coexistence of ferroelectric and magnetic ordering. This phenomenon has led to the development of various kinds of materials and conceptions of many novel applications such as development of a memory device utilizing the multifunctionality of the multiferroic materials leading to a multistate memory device with electrical writing and nondestructive magnetic reading operations. Though, interdependence of electrical- and magnetic-order parameters makes it difficult to accomplish the above and thus rendering the device to only two switchable states, recent research has shown that such problems can be circumvented by novel device designs such as formation of tunnel junction or by use of exchange bias. In this paper, we review the operational aspects of multiferroic memories as well as the materials used for these applications along with the designs that hold promise for the future memory devices.

  19. Simulation of Dislocation and Transformation Plasticity in Shape Memory Alloys

    National Research Council Canada - National Science Library

    Volkov, Alexander

    1999-01-01

    A model of deformation of shape memory alloys has been developed. It takes into account deformation due to the phase transformation and plastic deformation, produced by an external stress or by inter-phase stresses...

  20. Color Memory

    OpenAIRE

    Pate, Monica; Raclariu, Ana-Maria; Strominger, Andrew

    2017-01-01

    A transient color flux across null infinity in classical Yang-Mills theory is considered. It is shown that a pair of test `quarks' initially in a color singlet generically acquire net color as a result of the flux. A nonlinear formula is derived for the relative color rotation of the quarks. For weak color flux the formula linearizes to the Fourier transform of the soft gluon theorem. This color memory effect is the Yang-Mills analog of the gravitational memory effect.

  1. Multi-voxel decoding and the topography of maintained information during visual working memory

    Directory of Open Access Journals (Sweden)

    Sue-Hyun eLee

    2016-02-01

    Full Text Available The ability to maintain representations in the absence of external sensory stimulation, such as in working memory, is critical for guiding human behavior. Human functional brain imaging studies suggest that visual working memory can recruit a network of brain regions from visual to parietal to prefrontal cortex. In this review, we focus on the maintenance of representations during visual working memory and discuss factors determining the topography of those representations. In particular, we review recent studies employing multi-voxel pattern analysis that demonstrate decoding of the maintained content in visual cortex, providing support for a ‘sensory recruitment’ model of visual working memory. However, there is some evidence that maintained content can also be decoded in areas outside of visual cortex, including parietal and frontal cortex. We suggest that the ability to maintain representations during working memory is a general property of cortex, not restricted to specific areas, and argue that it is important to consider the nature of the information that must be maintained. Such information-content is critically determined by the task and the recruitment of specific regions during visual working memory will be both task- and stimulus-dependent. Thus, the common finding of maintained information in visual, but not parietal or prefrontal, cortex may be more of a reflection of the need to maintain specific types of visual information and not of a privileged role of visual cortex in maintenance.

  2. Multi-Voxel Decoding and the Topography of Maintained Information During Visual Working Memory.

    Science.gov (United States)

    Lee, Sue-Hyun; Baker, Chris I

    2016-01-01

    The ability to maintain representations in the absence of external sensory stimulation, such as in working memory, is critical for guiding human behavior. Human functional brain imaging studies suggest that visual working memory can recruit a network of brain regions from visual to parietal to prefrontal cortex. In this review, we focus on the maintenance of representations during visual working memory and discuss factors determining the topography of those representations. In particular, we review recent studies employing multi-voxel pattern analysis (MVPA) that demonstrate decoding of the maintained content in visual cortex, providing support for a "sensory recruitment" model of visual working memory. However, there is some evidence that maintained content can also be decoded in areas outside of visual cortex, including parietal and frontal cortex. We suggest that the ability to maintain representations during working memory is a general property of cortex, not restricted to specific areas, and argue that it is important to consider the nature of the information that must be maintained. Such information-content is critically determined by the task and the recruitment of specific regions during visual working memory will be both task- and stimulus-dependent. Thus, the common finding of maintained information in visual, but not parietal or prefrontal, cortex may be more of a reflection of the need to maintain specific types of visual information and not of a privileged role of visual cortex in maintenance.

  3. Reconfigurable photonic crystals enabled by pressure-responsive shape-memory polymers

    Science.gov (United States)

    Fang, Yin; Ni, Yongliang; Leo, Sin-Yen; Taylor, Curtis; Basile, Vito; Jiang, Peng

    2015-01-01

    Smart shape-memory polymers can memorize and recover their permanent shape in response to an external stimulus (for example, heat). They have been extensively exploited for a wide spectrum of applications ranging from biomedical devices to aerospace morphing structures. However, most of the existing shape-memory polymers are thermoresponsive and their performance is hindered by heat-demanding programming and recovery steps. Although pressure is an easily adjustable process variable such as temperature, pressure-responsive shape-memory polymers are largely unexplored. Here we report a series of shape-memory polymers that enable unusual ‘cold' programming and instantaneous shape recovery triggered by applying a contact pressure at ambient conditions. Moreover, the interdisciplinary integration of scientific principles drawn from two disparate fields—the fast-growing photonic crystal and shape-memory polymer technologies—enables fabrication of reconfigurable photonic crystals and simultaneously provides a simple and sensitive optical technique for investigating the intriguing shape-memory effects at nanoscale. PMID:26074349

  4. Multi-Voxel Decoding and the Topography of Maintained Information During Visual Working Memory

    Science.gov (United States)

    Lee, Sue-Hyun; Baker, Chris I.

    2016-01-01

    The ability to maintain representations in the absence of external sensory stimulation, such as in working memory, is critical for guiding human behavior. Human functional brain imaging studies suggest that visual working memory can recruit a network of brain regions from visual to parietal to prefrontal cortex. In this review, we focus on the maintenance of representations during visual working memory and discuss factors determining the topography of those representations. In particular, we review recent studies employing multi-voxel pattern analysis (MVPA) that demonstrate decoding of the maintained content in visual cortex, providing support for a “sensory recruitment” model of visual working memory. However, there is some evidence that maintained content can also be decoded in areas outside of visual cortex, including parietal and frontal cortex. We suggest that the ability to maintain representations during working memory is a general property of cortex, not restricted to specific areas, and argue that it is important to consider the nature of the information that must be maintained. Such information-content is critically determined by the task and the recruitment of specific regions during visual working memory will be both task- and stimulus-dependent. Thus, the common finding of maintained information in visual, but not parietal or prefrontal, cortex may be more of a reflection of the need to maintain specific types of visual information and not of a privileged role of visual cortex in maintenance. PMID:26912997

  5. Concurrent performance of two memory tasks: evidence for domain-specific working memory systems.

    Science.gov (United States)

    Cocchini, Gianna; Logie, Robert H; Della Sala, Sergio; MacPherson, Sarah E; Baddeley, Alan D

    2002-10-01

    Previous studies of dual-task coordination in working memory have shown a lack of dual-task interference when a verbal memory task is combined with concurrent perceptuomotor tracking. Two experiments are reported in which participants were required to perform pairwise combinations of (1) a verbal memory task, a visual memory task, and perceptuomotor tracking (Experiment 1), and (2) pairwise combinations of the two memory tasks and articulatory suppression (Experiment 2). Tracking resulted in no disruption of the verbal memory preload over and above the impact of a delay in recall and showed only minimal disruption of the retention of the visual memory load. Performing an ongoing verbal memory task had virtually no impact on retention of a visual memory preload or vice versa, indicating that performing two demanding memory tasks results in little mutual interference. Experiment 2 also showed minimal disruption when the two memory tasks were combined, although verbal memory (but not visual memory) was clearly disrupted by articulatory suppression interpolated between presentation and recall. These data suggest that a multiple-component working memory model provides a better account for performance in concurrent immediate memory tasks than do theories that assume a single processing and storage system or a limited-capacity attentional system coupled with activated memory traces.

  6. Histone modifier, the gatekeeper of good memory

    Institute of Scientific and Technical Information of China (English)

    Zilong Qiu

    2009-01-01

    @@ How do we learn and how do we remember? Learning and memory has long been one of the most fascinating questions in biology. In the 1970s, Squire LR et aL provided evidence that gene expression processes are critical for memory by showing that memory consolidation is disrupted when gene transcription or translation is blocked during the learning process [1].

  7. REGIONAL MULTILATERAL DEVELOPMENT BANKS. External Audit Reporting Could Be Expanded

    National Research Council Canada - National Science Library

    2001-01-01

    .... Worldwide, countries and institutions are recognizing the importance of providing independent, external assessments on not only financial reporting, but also on Internal control over an entity's...

  8. External and internal geometry of European adults.

    Science.gov (United States)

    Bertrand, Samuel; Skalli, Wafa; Delacherie, Laurent; Bonneau, Dominique; Kalifa, Gabriel; Mitton, David

    2006-12-15

    The primary objective of the study was to bring a deeper knowledge of the human anthropometry, investigating the external and internal body geometry of small women, mid-sized men and tall men. Sixty-four healthy European adults were recruited. External measurements were performed using classical anthropometric instruments. Internal measurements of the trunk bones were performed using a stereo-radiographic 3D reconstruction technique. Besides the original procedure presented in this paper for performing in vivo geometrical data acquisition on numerous volunteers, this study provides an extensive description of both external and internal (trunk skeleton) human body geometry for three morphotypes. Moreover, this study proposes a global external and internal geometrical description of 5th female 50th male and 95th male percentile subjects. This study resulted in a unique geometrical database enabling improvement for numerical models of the human body for crash test simulation and offering numerous possibilities in the anthropometry field.

  9. Episodic and semantic components of autobiographical memories and imagined future events in post-traumatic stress disorder.

    Science.gov (United States)

    Brown, Adam D; Addis, Donna Rose; Romano, Tracy A; Marmar, Charles R; Bryant, Richard A; Hirst, William; Schacter, Daniel L

    2014-01-01

    Individuals with post-traumatic stress disorder (PTSD) tend to retrieve autobiographical memories with less episodic specificity, referred to as overgeneralised autobiographical memory. In line with evidence that autobiographical memory overlaps with one's capacity to imagine the future, recent work has also shown that individuals with PTSD also imagine themselves in the future with less episodic specificity. To date most studies quantify episodic specificity by the presence of a distinct event. However, this method does not distinguish between the numbers of internal (episodic) and external (semantic) details, which can provide additional insights into remembering the past and imagining the future. This study employed the Autobiographical Interview (AI) coding scheme to the autobiographical memory and imagined future event narratives generated by combat veterans with and without PTSD. Responses were coded for the number of internal and external details. Compared to combat veterans without PTSD, those with PTSD generated more external than internal details when recalling past or imagining future events, and fewer internal details were associated with greater symptom severity. The potential mechanisms underlying these bidirectional deficits and clinical implications are discussed.

  10. Mental Imagery and Visual Working Memory

    OpenAIRE

    Keogh, Rebecca; Pearson, Joel

    2011-01-01

    Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance ...

  11. Fast Initialization of Bubble-Memory Systems

    Science.gov (United States)

    Looney, K. T.; Nichols, C. D.; Hayes, P. J.

    1986-01-01

    Improved scheme several orders of magnitude faster than normal initialization scheme. State-of-the-art commercial bubble-memory device used. Hardware interface designed connects controlling microprocessor to bubblememory circuitry. System software written to exercise various functions of bubble-memory system in comparison made between normal and fast techniques. Future implementations of approach utilize E2PROM (electrically-erasable programable read-only memory) to provide greater system flexibility. Fastinitialization technique applicable to all bubble-memory devices.

  12. Dynamic Delayed Duplicate Detection for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami

    2008-01-01

    Duplicate detection is an expensive operation of disk-based model checkers. It consists of comparing some potentially new states, the candidate states, to previous visited states. We propose a new approach to this technique called dynamic delayed duplicate detection. This one exploits some typical...

  13. Dynamic Delayed Duplicate Detection for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami

    2008-01-01

    Duplicate detection is an expensive operation of disk-based model checkers. It consists of comparing some potentially new states, the candidate states, to previous visited states. We propose a new approach to this technique called dynamic delayed duplicate detection. This one exploits some typica...... significantly better than some previously published algorithms....

  14. External Memory Graph Algorithms and Range Searching Data Structures

    DEFF Research Database (Denmark)

    Walderveen, Freek van

    ). In order to present (for example geographic) data to a user, it is often necessary to select only a relatively small part of a dataset|such as all post oces in the region visible on the user's screen|and return some statictic about this part|such as the distance between the two furthest post oces...... in the region, which may help a postal company in determining what delivery time they can guarantee for their customers. Even in non-geometric settings, the part of the data that needs to be selected is often easily described geometrically, for example in database queries asking for records matching multiple......Every day larger amounts of data are generated that describe our world in terms of networks or graphs. Think for example about maps of roads or rivers, social networks, or the internet (either as a network of computers or as a network of hyperlinks). Besides this, also surface models...

  15. External memory K-bisimulation reduction of big graphs

    NARCIS (Netherlands)

    Luo, Y.; Fletcher, G.H.L.; Hidders, A.J.H.; Wu, Y.; De Bra, P.M.E.

    2013-01-01

    In this paper, we present, to our knowledge, the first known I/O efficient solutions for computing the k-bisimulation partition of a massive directed graph, and performing maintenance of such a partition upon updates to the underlying graph. Ubiquitous in the theory and application of graph data,

  16. Nanographene charge trapping memory with a large memory window

    International Nuclear Information System (INIS)

    Meng, Jianling; Yang, Rong; Zhao, Jing; He, Congli; Wang, Guole; Shi, Dongxia; Zhang, Guangyu

    2015-01-01

    Nanographene is a promising alternative to metal nanoparticles or semiconductor nanocrystals for charge trapping memory. In general, a high density of nanographene is required in order to achieve high charge trapping capacity. Here, we demonstrate a strategy of fabrication for a high density of nanographene for charge trapping memory with a large memory window. The fabrication includes two steps: (1) direct growth of continuous nanographene film; and (2) isolation of the as-grown film into high-density nanographene by plasma etching. Compared with directly grown isolated nanographene islands, abundant defects and edges are formed in nanographene under argon or oxygen plasma etching, i.e. more isolated nanographene islands are obtained, which provides more charge trapping sites. As-fabricated nanographene charge trapping memory shows outstanding memory properties with a memory window as wide as ∼9 V at a relative low sweep voltage of ±8 V, program/erase speed of ∼1 ms and robust endurance of >1000 cycles. The high-density nanographene charge trapping memory provides an outstanding alternative for downscaling technology beyond the current flash memory. (paper)

  17. Radiation Tolerant Embedded Memory

    National Research Council Canada - National Science Library

    Smith, Brian

    2003-01-01

    ... event effects, and will scale to smaller geometries to provide the same performance. we then designed arrays of that memory to build up blocks to be used in complex Cool-RAD(tm) parts such as microprocessors and digital signal processors.

  18. Shape Memory of Human Red Blood Cells

    OpenAIRE

    Fischer, Thomas M.

    2004-01-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spher...

  19. Oscillatory Reinstatement Enhances Declarative Memory.

    Science.gov (United States)

    Javadi, Amir-Homayoun; Glen, James C; Halkiopoulos, Sara; Schulz, Mei; Spiers, Hugo J

    2017-10-11

    Declarative memory recall is thought to involve the reinstatement of neural activity patterns that occurred previously during encoding. Consistent with this view, greater similarity between patterns of activity recorded during encoding and retrieval has been found to predict better memory performance in a number of studies. Recent models have argued that neural oscillations may be crucial to reinstatement for successful memory retrieval. However, to date, no causal evidence has been provided to support this theory, nor has the impact of oscillatory electrical brain stimulation during encoding and retrieval been assessed. To explore this we used transcranial alternating current stimulation over the left dorsolateral prefrontal cortex of human participants [ n = 70, 45 females; age mean (SD) = 22.12 (2.16)] during a declarative memory task. Participants received either the same frequency during encoding and retrieval (60-60 or 90-90 Hz) or different frequencies (60-90 or 90-60 Hz). When frequencies matched there was a significant memory improvement (at both 60 and 90 Hz) relative to sham stimulation. No improvement occurred when frequencies mismatched. Our results provide support for the role of oscillatory reinstatement in memory retrieval. SIGNIFICANCE STATEMENT Recent neurobiological models of memory have argued that large-scale neural oscillations are reinstated to support successful memory retrieval. Here we used transcranial alternating current stimulation (tACS) to test these models. tACS has recently been shown to induce neural oscillations at the frequency stimulated. We stimulated over the left dorsolateral prefrontal cortex during a declarative memory task involving learning a set of words. We found that tACS applied at the same frequency during encoding and retrieval enhances memory. We also find no difference between the two applied frequencies. Thus our results are consistent with the proposal that reinstatement of neural oscillations during retrieval

  20. Age differences in perceptions of memory strategy effectiveness for recent and remote memory.

    Science.gov (United States)

    Lineweaver, Tara T; Horhota, Michelle; Crumley, Jessica; Geanon, Catherine T; Juett, Jacqueline J

    2018-03-01

    We examined whether young and older adults hold different beliefs about the effectiveness of memory strategies for specific types of memory tasks and whether memory strategies are perceived to be differentially effective for young, middle-aged, and older targets. Participants rated the effectiveness of five memory strategies for 10 memory tasks at three target ages (20, 50, and 80 years old). Older adults did not strongly differentiate strategy effectiveness, viewing most strategies as similarly effective across memory tasks. Young adults held strategy-specific beliefs, endorsing external aids and physical health as more effective than a positive attitude or internal strategies, without substantial differentiation based on task. We also found differences in anticipated strategy effectiveness for targets of different ages. Older adults described cognitive and physical health strategies as more effective for older than middle-aged targets, whereas young adults expected these strategies to be equally effective for middle-aged and older target adults.

  1. Energy providers: customer expectations

    International Nuclear Information System (INIS)

    Pridham, N.F.

    1997-01-01

    The deregulation of the gas and electric power industries, and how it will impact on customer service and pricing rates was discussed. This paper described the present situation, reviewed core competencies, and outlined future expectations. The bottom line is that major energy consumers are very conscious of energy costs and go to great lengths to keep them under control. At the same time, solutions proposed to reduce energy costs must benefit all classes of consumers, be they industrial, commercial, institutional or residential. Deregulation and competition at an accelerated pace is the most likely answer. This may be forced by external forces such as foreign energy providers who are eager to enter the Canadian energy market. It is also likely that the competition and convergence between gas and electricity is just the beginning, and may well be overshadowed by other deregulated industries as they determine their core competencies

  2. Endogenous-cue prospective memory involving incremental updating of working memory: an fMRI study.

    Science.gov (United States)

    Halahalli, Harsha N; John, John P; Lukose, Ammu; Jain, Sanjeev; Kutty, Bindu M

    2015-11-01

    Prospective memory paradigms are conventionally classified on the basis of event-, time-, or activity-based intention retrieval. In the vast majority of such paradigms, intention retrieval is provoked by some kind of external event. However, prospective memory retrieval cues that prompt intention retrieval in everyday life are commonly endogenous, i.e., linked to a specific imagined retrieval context. We describe herein a novel prospective memory paradigm wherein the endogenous cue is generated by incremental updating of working memory, and investigated the hemodynamic correlates of this task. Eighteen healthy adult volunteers underwent functional magnetic resonance imaging while they performed a prospective memory task where the delayed intention was triggered by an endogenous cue generated by incremental updating of working memory. Working memory and ongoing task control conditions were also administered. The 'endogenous-cue prospective memory condition' with incremental working memory updating was associated with maximum activations in the right rostral prefrontal cortex, and additional activations in the brain regions that constitute the bilateral fronto-parietal network, central and dorsal salience networks as well as cerebellum. In the working memory control condition, maximal activations were noted in the left dorsal anterior insula. Activation of the bilateral dorsal anterior insula, a component of the central salience network, was found to be unique to this 'endogenous-cue prospective memory task' in comparison to previously reported exogenous- and endogenous-cue prospective memory tasks without incremental working memory updating. Thus, the findings of the present study highlight the important role played by the dorsal anterior insula in incremental working memory updating that is integral to our endogenous-cue prospective memory task.

  3. A direct comparison of short-term audiomotor and visuomotor memory.

    Science.gov (United States)

    Ward, Amanda M; Loucks, Torrey M; Ofori, Edward; Sosnoff, Jacob J

    2014-04-01

    Audiomotor and visuomotor short-term memory are required for an important variety of skilled movements but have not been compared in a direct manner previously. Audiomotor memory capacity might be greater to accommodate auditory goals that are less directly related to movement outcome than for visually guided tasks. Subjects produced continuous isometric force with the right index finger under auditory and visual feedback. During the first 10 s of each trial, subjects received continuous auditory or visual feedback. For the following 15 s, feedback was removed but the force had to be maintained accurately. An internal effort condition was included to test memory capacity in the same manner but without external feedback. Similar decay times of ~5-6 s were found for vision and audition but the decay time for internal effort was ~4 s. External feedback thus provides an advantage in maintaining a force level after feedback removal, but may not exclude some contribution from a sense of effort. Short-term memory capacity appears longer than certain previous reports but there may not be strong distinctions in capacity across different sensory modalities, at least for isometric force.

  4. Environmental external effects from wind power based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1998-01-01

    of the Danish part of the project is to implement the framework for externality evaluation, for three different power plants located in Denmark. The paper will focus on the assessment of the impacts of the whole fuel cycles for wind, natural gas and biogas. Priority areas for environmental impact assessment......The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective...

  5. Atomic crystals resistive switching memory

    International Nuclear Information System (INIS)

    Liu Chunsen; Zhang David Wei; Zhou Peng

    2017-01-01

    Facing the growing data storage and computing demands, a high accessing speed memory with low power and non-volatile character is urgently needed. Resistive access random memory with 4F 2 cell size, switching in sub-nanosecond, cycling endurances of over 10 12 cycles, and information retention exceeding 10 years, is considered as promising next-generation non-volatile memory. However, the energy per bit is still too high to compete against static random access memory and dynamic random access memory. The sneak leakage path and metal film sheet resistance issues hinder the further scaling down. The variation of resistance between different devices and even various cycles in the same device, hold resistive access random memory back from commercialization. The emerging of atomic crystals, possessing fine interface without dangling bonds in low dimension, can provide atomic level solutions for the obsessional issues. Moreover, the unique properties of atomic crystals also enable new type resistive switching memories, which provide a brand-new direction for the resistive access random memory. (topical reviews)

  6. External corners as heat bridges

    Energy Technology Data Exchange (ETDEWEB)

    Berber, J.

    1984-08-01

    The maximum additional heat loss in vertical external corners depending on wall thickness is determined. In order to amire at a low k-value, a much smaller wall thickness is required in externally insulated walls than in monolithic constructions; the greater loss of heat bridge with external insulation stands in contrast to a higher loss in thick, monolithic walls. In relation to total losses, the additional losses through external corners are practically negligible.

  7. Synthetic vision and memory for autonomous virtual humans

    OpenAIRE

    PETERS, CHRISTOPHER; O'SULLIVAN, CAROL ANN

    2002-01-01

    PUBLISHED A memory model based on ?stage theory?, an influential concept of memory from the field of cognitive psychology, is presented for application to autonomous virtual humans. The virtual human senses external stimuli through a synthetic vision system. The vision system incorporates multiple modes of vision in order to accommodate a perceptual attention approach. The memory model is used to store perceived and attended object information at different stages in a filtering...

  8. [External pancreatic fistulas management].

    Science.gov (United States)

    Stepan, E V; Ermolov, A S; Rogal', M L; Teterin, Yu S

    The main principles of treatment of external postoperative pancreatic fistulas are viewed in the article. Pancreatic trauma was the reason of pancreatic fistula in 38.7% of the cases, operations because of acute pancreatitis - in 25.8%, and pancreatic pseudocyst drainage - in 35.5%. 93 patients recovered after the treatment. Complex conservative treatment of EPF allowed to close fistulas in 74.2% of the patients with normal patency of the main pancreatic duct (MPD). The usage of octreotide 600-900 mcg daily for at least 5 days to decrease pancreatic secretion was an important part of the conservative treatment. Endoscopic papillotomy was performed in patients with major duodenal papilla obstruction and interruption of transporting of pancreatic secretion to duodenum. Stent of the main pancreatic duct was indicated in patients with extended pancreatic duct stenosis to normalize transport of pancreatic secretion to duodenum. Surgical formation of anastomosis between distal part of the main pancreatic duct and gastro-intestinal tract was carried out when it was impossible to fulfill endoscopic stenting of pancreatic duct either because of its interruption and diastasis between its ends, or in the cases of unsuccessful conservative treatment of external pancreatic fistula caused by drainage of pseudocyst.

  9. Internalizing Externalities through Payments for Environmental Services

    Directory of Open Access Journals (Sweden)

    Sudarsono Soedomo

    2012-08-01

    Full Text Available Forest ecosystems, including plantation forests, provide goods and services that are marketable and non-marketable. Positive externalities produced by forest ecosystems are rarely considered in pricing of marketable products that result in economic inefficiencies. Internalizing externalities is required to improve the economic efficiency. The traditional way to internalize an externality is by providing subsidies or imposing taxes. Recently, payments for environmental services  are receiving more attention as an instrument for internalizing externalities provided by forest ecosystems. This promising alternative to improve our environment needs to be studied more extensively. In this paper, it can be indicated theoretically that the Pigovian tax, as a traditional way of addressing environmental problems, is able to mimic the result derived from the employment of environmental services payment. The difference is that environmental services payment improves the welfare of environmental service producers, whereas the Pigovian tax reduces it. A positive Pigovian tax increases the optimal rotation, which is positively associated with environmental improvement, but certainly reduces forest owner's welfare. This difference should be taken into account in the public policymaking so that perverse incentive may be avoided. Payment for environmental services  as an additional income to forest growers, not as alternative source of income, is a potential tool to address simultaneously issues of environment and poverty that are frequently contested.Keywords: externalities, payments for environmental services, tax, perverse incentive, social welfare

  10. The spectro-contextual encoding and retrieval theory of episodic memory.

    Science.gov (United States)

    Watrous, Andrew J; Ekstrom, Arne D

    2014-01-01

    The spectral fingerprint hypothesis, which posits that different frequencies of oscillations underlie different cognitive operations, provides one account for how interactions between brain regions support perceptual and attentive processes (Siegel etal., 2012). Here, we explore and extend this idea to the domain of human episodic memory encoding and retrieval. Incorporating findings from the synaptic to cognitive levels of organization, we argue that spectrally precise cross-frequency coupling and phase-synchronization promote the formation of hippocampal-neocortical cell assemblies that form the basis for episodic memory. We suggest that both cell assembly firing patterns as well as the global pattern of brain oscillatory activity within hippocampal-neocortical networks represents the contents of a particular memory. Drawing upon the ideas of context reinstatement and multiple trace theory, we argue that memory retrieval is driven by internal and/or external factors which recreate these frequency-specific oscillatory patterns which occur during episodic encoding. These ideas are synthesized into a novel model of episodic memory (the spectro-contextual encoding and retrieval theory, or "SCERT") that provides several testable predictions for future research.

  11. Environmental externalities and renewables: A policy perspective

    International Nuclear Information System (INIS)

    Sanghi, A.K.

    1992-01-01

    New York state electric utilities are required to incorporate the consideration of environmental externality costs in their bidding programs for new capacity. A natural extension of this policy would be to consider environmental externality costs in the state's implementation of federal regulations under the Public Utilities Regulatory Policies Act (PURPA). A more direct but more politically difficult approach would be the use of environmental taxes. These two approaches are discussed for more fully incorporating environmental externalities in New York's energy planning process. Under PURPA, utilities have a general obligation to purchase energy from interconnected qualifying facilities on the basis of long-run avoided cost (LRAC) estimates. The New York State Public Service Commission is currently updating the LRAC estimates, which do not account for the costs of complying with the 1990 amendments of the Clean Air Act (CAA) or for environmental externality costs associated with underlying generation sources. Environmental externality LRACs are estimated based on SO 2 , NO x , and CO 2 emissions; estimates of CAA compliance are relatively small in comparison. The use of taxes to reduce emissions by making pollution more expensive than abatement is analyzed, with reference to both general revenue and trust fund types of tax mechanisms. The ways the two mechanisms affect development of wind power resources is illustrated to provide further insight into the correct application of environmental externalities in energy planning. 8 refs., 3 figs., 2 tabs

  12. External conference: Geneva University

    CERN Multimedia

    2006-01-01

    ECOLE DE PHYSIQUE Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 - Tél : 022 379 62 73 - Fax: 022 379 69 92 Monday 12 June 2006 PARTICLE PHYSICS COLLOQUIUM at 17:00 - Stückelberg Auditorium Quantum computers - dream and realization Prof. R. Blatt / University of Innsbruck, Austria Computational operations always rely on real physical processes, which are data input, data representation in a memory, data manipulation using algorithms and finally, the data output. With conventional computers all the processes are classical processes and can be described accordingly. Theoretically, it is known for several years now that certain computations could be processed much more efficiently using quantum mechanical operations. This requires the implementation of quantum bits (qubits), quantum registers and quantum gates and the development of quantum algorithms. Several approaches for the implementation of quantum computers will be presented, with special emphasis o...

  13. Generation and memory for contextual detail.

    Science.gov (United States)

    Mulligan, Neil W

    2004-07-01

    Generation enhances item memory but may not enhance other aspects of memory. In 12 experiments, the author investigated the effect of generation on context memory, motivated in part by the hypothesis that generation produces a trade-off in encoding item and contextual information. Participants generated some study words (e.g., hot-c__) and read others (e.g., hot-cold). Generation consistently enhanced item memory but did not enhance context memory. More specifically, generation disrupted context memory for the color of the target word but did not affect context memory for location, background color, and cue-word color. The specificity of the negative generation effect in context memory argues against a general item-context trade-off. A processing account of generation meets greater success. In addition, the results provide no evidence that generation enhances recollection of contextual details. Copyright 2004 APA, all rights reserved

  14. Neurostimulation for Memory Enhancement in Epilepsy.

    Science.gov (United States)

    Meisenhelter, Stephen; Jobst, Barbara C

    2018-04-19

    Memory is one of the top concerns of epilepsy patients, but there are no known treatments to directly alleviate the memory deficits associated with epilepsy. Neurostimulation may provide new therapeutic tools to enhance memory in epilepsy patients. Here, we critically review recent investigations of memory enhancement using transcranial electrical stimulation (tES), transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS), chronic intracranial stimulation, and acute intracranial stimulation. Existing literature suggests that transcranial direct current stimulation (tDCS) produces a small enhancement in memory in neuropsychological patients, but transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS) have not been found to have an effect on memory. Most studies of transcranial magnetic stimulation (TMS) have found that TMS has no positive effect on memory. Vagus nerve stimulation can acutely enhance memory, while chronic therapy does not appear to alter memory performance. We found that there is the most evidence for significant memory enhancement using intracranial stimulation techniques, especially chronic stimulation of the fornix and task-responsive stimulation of the lateral temporal lobe. Presently, there are no existing therapeutic options for directly treating epilepy-related memory deficits. While neurostimulation technologies for memory enhancement are largely still in the experimental phase, neurostimulation appears promising as a future technique for treating epilepsy-related memory deficits.

  15. Working Memory and Behavioural Problems in Relation to Malay Writing of Primary School Children

    Science.gov (United States)

    Ling, Teo-Sieak; Jiar, Yeo-Kee

    2017-01-01

    Deficit in working memory is common among young children across multiple abilities. Teachers have pointed to poor memory as one contributing factor to inattentiveness and short attention spans as well as some behavioural problems among students. This study aimed to explore the relationship among working memory, externalizing and internalizing…

  16. Addiction memory as a specific, individually learned memory imprint.

    Science.gov (United States)

    Böning, J

    2009-05-01

    The construct of "addiction memory" (AM) and its importance for relapse occurrence has been the subject of discussion for the past 30 years. Neurobiological findings from "social neuroscience" and biopsychological learning theory, in conjunction with construct-valid behavioral pharmacological animal models, can now also provide general confirmation of addiction memory as a pathomorphological correlate of addiction disorders. Under multifactorial influences, experience-driven neuronal learning and memory processes of emotional and cognitive processing patterns in the specific individual "set" and "setting" play an especially pivotal role in this connection. From a neuropsychological perspective, the episodic (biographical) memory, located at the highest hierarchical level, is of central importance for the formation of the AM in certain structural and functional areas of the brain and neuronal networks. Within this context, neuronal learning and conditioning processes take place more or less unconsciously and automatically in the preceding long-term-memory systems (in particular priming and perceptual memory). They then regulate the individually programmed addiction behavior implicitly and thus subsequently stand for facilitated recollection of corresponding, previously stored cues or context situations. This explains why it is so difficult to treat an addiction memory, which is embedded above all in the episodic memory, from the molecular carrier level via the neuronal pattern level through to the psychological meaning level, and has thus meanwhile become a component of personality.

  17. Working Memory: A Selective Review.

    Science.gov (United States)

    Kent, Phillip L

    2016-01-01

    The purpose of this paper is to provide a selective overview of the evolution of the concept and assessment of working memory, and how its assessment has been confused with the assessment of some components of attention. A literature search using PsychNet Gold was conducted using the terms working memory. In addition, the writer reviewed recommendations from a sampling of recent neuropsychology texts in regard to the assessment of attention and working memory, as well as the two most recent editions of the Wechsler Memory Scale. It is argued that many clinicians have an incomplete understanding of the relationship between attention and working memory, and often conflate the two in assessment and treatment. Suggestions were made for assessing these abilities.

  18. All-printed paper memory

    KAUST Repository

    He, Jr-Hau

    2016-08-11

    All-printed paper-based substrate memory devices are described. In an embodiment, a paper-based memory device is prepared by coating one or more areas of a paper substrate with a conductor material such as a carbon paste, to form a first electrode of a memory, depositing a layer of insulator material, such as titanium dioxide, over one or more areas of the conductor material, and depositing a layer of metal over one or more areas of the insulator material to form a second electrode of the memory. In an embodiment, the device can further include diodes printed between the insulator material and the second electrode, and the first electrode and the second electrodes can be formed as a crossbar structure to provide a WORM memory. The various layers and the diodes can be printed onto the paper substrate by, for example, an ink jet printer.

  19. External event analysis methods for NUREG-1150

    International Nuclear Information System (INIS)

    Bohn, M.P.; Lambright, J.A.

    1989-01-01

    The US Nuclear Regulatory Commission is sponsoring probabilistic risk assessments of six operating commercial nuclear power plants as part of a major update of the understanding of risk as provided by the original WASH-1400 risk assessments. In contrast to the WASH-1400 studies, at least two of the NUREG-1150 risk assessments will include an analysis of risks due to earthquakes, fires, floods, etc., which are collectively known as eternal events. This paper summarizes the methods to be used in the external event analysis for NUREG-1150 and the results obtained to date. The two plants for which external events are being considered are Surry and Peach Bottom, a PWR and BWR respectively. The external event analyses (through core damage frequency calculations) were completed in June 1989, with final documentation available in September. In contrast to most past external event analyses, wherein rudimentary systems models were developed reflecting each external event under consideration, the simplified NUREG-1150 analyses are based on the availability of the full internal event PRA systems models (event trees and fault trees) and make use of extensive computer-aided screening to reduce them to sequence cut sets important to each external event. This provides two major advantages in that consistency and scrutability with respect to the internal event analysis is achieved, and the full gamut of random and test/maintenance unavailabilities are automatically included, while only those probabilistically important survive the screening process. Thus, full benefit of the internal event analysis is obtained by performing the internal and external event analyses sequentially

  20. External Measures of Cognition

    Directory of Open Access Journals (Sweden)

    Osvaldo eCairo

    2011-10-01

    Full Text Available The human brain is undoubtedly the most impressive, complex and intricate organ that has evolved over time. It is also probably the least understood, and for that reason, the one that is currently attracting the most attention. In fact, the number of comparative analyses that focus on the evolution of brain size in Homo sapiens and other species has increased dramatically in recent years. In neuroscience, no other issue has generated so much interest and been the topic of so many heated debates as the difference in brain size between socially defined population groups, both its connotations and implications. For over a century, external measures of cognition have been related to intelligence. However, it is still unclear whether these measures actually correspond to cognitive abilities. In summary, this paper must be reviewed with this premise in mind.

  1. Hanford External Dosimetry Program

    International Nuclear Information System (INIS)

    Fix, J.J.

    1990-10-01

    This document describes the Hanford External Dosimetry Program as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) and its Hanford contractors. Program services include administrating the Hanford personnel dosimeter processing program and ensuring that the related dosimeter data accurately reflect occupational dose received by Hanford personnel or visitors. Specific chapters of this report deal with the following subjects: personnel dosimetry organizations at Hanford and the associated DOE and contractor exposure guidelines; types, characteristics, and procurement of personnel dosimeters used at Hanford; personnel dosimeter identification, acceptance testing, accountability, and exchange; dosimeter processing and data recording practices; standard sources, calibration factors, and calibration processes (including algorithms) used for calibrating Hanford personnel dosimeters; system operating parameters required for assurance of dosimeter processing quality control; special dose evaluation methods applied for individuals under abnormal circumstances (i.e., lost results, etc.); and methods for evaluating personnel doses from nuclear accidents. 1 ref., 14 figs., 5 tabs

  2. Bevalac external beamline optics

    Energy Technology Data Exchange (ETDEWEB)

    Kalnins, J.G.; Krebs, G.F.; Tekawa, M.M.; Alonso, J.R.

    1987-04-01

    This handbook is intended as an aid for tuning the external particle beam (EPB) lines at the Lawrence Berkeley Laboratory's Bevalac. The information contained within will be useful to the Bevalac's Main Control Room and experimenters alike. First, some general information is given concerning the EPB lines and beam optics. Next, each beam line is described in detail: schematics of the beam line components are shown, all the variables required to run a beam transport program are presented, beam envelopes are given with wire chamber pictures and magnet currents, focal points and magnifications. Some preliminary scaling factors are then presented which should aid in choosing a given EPB magnet's current for a given central Bevalac field. Finally, some tuning hints are suggested.

  3. Bevalac external beamline optics

    International Nuclear Information System (INIS)

    Kalnins, J.G.; Krebs, G.F.; Tekawa, M.M.; Alonso, J.R.

    1987-04-01

    This handbook is intended as an aid for tuning the external particle beam (EPB) lines at the Lawrence Berkeley Laboratory's Bevalac. The information contained within will be useful to the Bevalac's Main Control Room and experimenters alike. First, some general information is given concerning the EPB lines and beam optics. Next, each beam line is described in detail: schematics of the beam line components are shown, all the variables required to run a beam transport program are presented, beam envelopes are given with wire chamber pictures and magnet currents, focal points and magnifications. Some preliminary scaling factors are then presented which should aid in choosing a given EPB magnet's current for a given central Bevalac field. Finally, some tuning hints are suggested

  4. ExternE: Externalities of energy Vol. 3. Coal and lignite

    International Nuclear Information System (INIS)

    Berry, J.; Holland, M.; Lee, D.

    1995-01-01

    methodological issues was reached on both sides of the Atlantic. Since 1993 the study has continued in Europe as the ExternE-Project, and now involves an international team of more than 30 organisations. The current study has three main objectives: 1. to design a unified methodology for quantifying the various social costs associated with the production and consumption of energy; 2. to use the methodology to evaluate the external costs of incremental use of different fuel cycles in different locations in the European Union; 3. to identify critical methodological issues and research requirements. At the same time as the publication of the present report, further reports are being published on the other major fuel cycles for electricity generation, including uranium, oil, gas, wind and hydro. A further volume, providing greater detail on the methodology used for assessment of the impacts of the fossil fuel cycles and their valuation is also being published. Additional reports on other fuel cycles, and implementation of the methodology in different countries will follow shortly. This document assesses the progress made in quantifying environmental and health damages associated with the coal and lignite fuel cycles. Estimates of impacts have been made following critical review of existing data and models rather than from original basic research. This review has been performed by a multi-disciplinary team including specialists in the fields of health, forestry, ecology, materials science, atmospheric chemistry and physics, energy technology, computer science and economics. Wherever possible we have used exactly the same methodology to quantify the same form of damage for each fuel cycle and for each location. However, some differences will be observed in the assessment of the fuel cycles considered in this report. These arise largely through the status of development of the methodology when certain parts of the work were completed. Wherever possible these differences have been

  5. Holographic memories

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Berg, R.H.; Hvilsted, Søren

    1999-01-01

    A Two-dimensional holographic memory for archival storage is described. Assuming a coherent transfer function, an A4 page can be stored at high resolution in an area of 1 mm(2). Recently developed side-chain liquid crystalline azobenzene polyesters are found to be suitable media for holographic...

  6. Sharing Memories

    DEFF Research Database (Denmark)

    Rodil, Kasper; Nielsen, Emil Byskov; Nielsen, Jonathan Bernstorff

    2018-01-01

    in which it was to be contextualized and through a close partnership between aphasics and their caretakers. The underlying design methodology for the MemoryBook is Participatory Design manifested through the collaboration and creations by two aphasic residents and one member of the support staff. The idea...

  7. Memory consolidation

    NARCIS (Netherlands)

    Takashima, A.; Bakker, I.; Schmid, H.-J.

    2016-01-01

    In order to make use of novel experiences and knowledge to guide our future behavior, we must keep large amounts of information accessible for retrieval. The memory system that stores this information needs to be flexible in order to rapidly incorporate incoming information, but also requires that

  8. Skilled Memory.

    Science.gov (United States)

    1980-11-06

    Woodworth, R. S. Experimental Psychology. New York: Henry Holt and Co., 1938. Yates, F. A. The art of memory. London: Rutledge and Kegan Paul, 1966. 50...Group 1 Psychologist (TAEG) ON! Branch Office Dept. of the Navy 1030 East Green Street Orlando, FL 32813 Pasadena, CA 91101 1 Dr. Richard Sorensen I

  9. Frameworking memory and serotonergic markers.

    Science.gov (United States)

    Meneses, Alfredo

    2017-07-26

    The evidence for neural markers and memory is continuously being revised, and as evidence continues to accumulate, herein, we frame earlier and new evidence. Hence, in this work, the aim is to provide an appropriate conceptual framework of serotonergic markers associated with neural activity and memory. Serotonin (5-hydroxytryptamine [5-HT]) has multiple pharmacological tools, well-characterized downstream signaling in mammals' species, and established 5-HT neural markers showing new insights about memory functions and dysfunctions, including receptors (5-HT1A/1B/1D, 5-HT2A/2B/2C, and 5-HT3-7), transporter (serotonin transporter [SERT]) and volume transmission present in brain areas involved in memory. Bidirectional influence occurs between 5-HT markers and memory/amnesia. A growing number of researchers report that memory, amnesia, or forgetting modifies neural markers. Diverse approaches support the translatability of using neural markers and cerebral functions/dysfunctions, including memory formation and amnesia. At least, 5-HT1A, 5-HT4, 5-HT6, and 5-HT7 receptors and SERT seem to be useful neural markers and therapeutic targets. Hence, several mechanisms cooperate to achieve synaptic plasticity or memory, including changes in the expression of neurotransmitter receptors and transporters.

  10. Emerging memory technologies design, architecture, and applications

    CERN Document Server

    2014-01-01

    This book explores the design implications of emerging, non-volatile memory (NVM) technologies on future computer memory hierarchy architecture designs. Since NVM technologies combine the speed of SRAM, the density of DRAM, and the non-volatility of Flash memory, they are very attractive as the basis for future universal memories. This book provides a holistic perspective on the topic, covering modeling, design, architecture and applications. The practical information included in this book will enable designers to exploit emerging memory technologies to improve significantly the performance/power/reliability of future, mainstream integrated circuits. • Provides a comprehensive reference on designing modern circuits with emerging, non-volatile memory technologies, such as MRAM and PCRAM; • Explores new design opportunities offered by emerging memory technologies, from a holistic perspective; • Describes topics in technology, modeling, architecture and applications; • Enables circuit designers to ex...

  11. A Pilot Memory Café for People with Learning Disabilities and Memory Difficulties

    Science.gov (United States)

    Kiddle, Hannah; Drew, Neil; Crabbe, Paul; Wigmore, Jonathan

    2016-01-01

    Memory cafés have been found to normalise experiences of dementia and provide access to an accepting social network. People with learning disabilities are at increased risk of developing dementia, but the possible benefits of attending a memory café are not known. This study evaluates a 12-week pilot memory café for people with learning…

  12. External Monitoring and Dynamic Behavior in Mutual Funds

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2016-01-01

    Full Text Available This paper studies the impact of external monitoring on the behavior in mutual funds. Specifically, we investigate how and why external monitoring can alleviate contracting inefficiency caused by information asymmetry between investors and the manager. It is shown that efficiency loss emerges when investors contract with the manager just relying on her investment return history. The establishment of external monitoring that provides investors more information about the manager’s ability can improve contracting efficiency, which converges to first-best as external monitoring strengthens. These results provide strong support for tightening supervision in mutual fund industry.

  13. External Science Courses: The Practicals Problem.

    Science.gov (United States)

    Kember, David

    1982-01-01

    Describes three methods for offering practical work for external science courses: residential sessions on campus, local centers, and use of home laboratory kits. The advantages and disadvantages of each are discussed and examples of each in operation are given. A 21-item bibliography is provided. (EAO)

  14. External financing of projects on cogeneration

    International Nuclear Information System (INIS)

    Contreras Olmedo, D.

    1993-01-01

    The Spanish Institute for Energy Saving and Diversification (IDAE), provides technical advisement and economical support to those industries requiring an improvement in the energy efficiency of their production chain. This paper focusses on administrative procedures to get external financing as one way to undertake the construction of cogeneration plants. Relationships among user, promoter and financier should be developed according to the outlined procedures. (Author)

  15. External Program Reviews (2012) | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-06-24

    Jun 24, 2016 ... These final evaluations are our primary accountability mechanism in terms of the results, effectiveness, and relevance of program spending. External program reviews aim to: account to IDRC's Board of Governors for the implementation of the program prospectus; provide input into programming for learning ...

  16. Social Ontology Documentation for Knowledge Externalization

    Science.gov (United States)

    Aranda-Corral, Gonzalo A.; Borrego-Díaz, Joaquín; Jiménez-Mavillard, Antonio

    Knowledge externalization and organization is a major challenge that companies must face. Also, they have to ask whether is possible to enhance its management. Mechanical processing of information represents a chance to carry out these tasks, as well as to turn intangible knowledge assets into real assets. Machine-readable knowledge provides a basis to enhance knowledge management. A promising approach is the empowering of Knowledge Externalization by the community (users, employees). In this paper, a social semantic tool (called OntoxicWiki) for enhancing the quality of knowledge is presented.

  17. Resting state EEG correlates of memory consolidation.

    Science.gov (United States)

    Brokaw, Kate; Tishler, Ward; Manceor, Stephanie; Hamilton, Kelly; Gaulden, Andrew; Parr, Elaine; Wamsley, Erin J

    2016-04-01

    Numerous studies demonstrate that post-training sleep benefits human memory. At the same time, emerging data suggest that other resting states may similarly facilitate consolidation. In order to identify the conditions under which non-sleep resting states benefit memory, we conducted an EEG (electroencephalographic) study of verbal memory retention across 15min of eyes-closed rest. Participants (n=26) listened to a short story and then either rested with their eyes closed, or else completed a distractor task for 15min. A delayed recall test was administered immediately following the rest period. We found, first, that quiet rest enhanced memory for the short story. Improved memory was associated with a particular EEG signature of increased slow oscillatory activity (rest can facilitate memory, and that this may occur via an active process of consolidation supported by slow oscillatory EEG activity and characterized by decreased attention to the external environment. Slow oscillatory EEG rhythms are proposed to facilitate memory consolidation during sleep by promoting hippocampal-cortical communication. Our findings suggest that EEG slow oscillations could play a significant role in memory consolidation during other resting states as well. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Thermomechanical behavior of a two-way shape memory composite actuator

    International Nuclear Information System (INIS)

    Ge, Qi; Westbrook, Kristofer K; Dunn, Martin L; Jerry Qi, H; Mather, Patrick T

    2013-01-01

    Shape memory polymers (SMPs) are a class of smart materials that can fix a temporary shape and recover to their permanent (original) shape in response to an environmental stimulus such as heat, electricity, or irradiation, among others. Most SMPs developed in the past can only demonstrate the so-called one-way shape memory effect; i.e., one programming step can only yield one shape memory cycle. Recently, one of the authors (Mather) developed a SMP that exhibits both one-way shape memory (1W-SM) and two-way shape memory (2W-SM) effects (with the assistance of an external load). This SMP was further used to develop a free-standing composite actuator with a nonlinear reversible actuation under thermal cycling. In this paper, a theoretical model for the PCO SMP based composite actuator was developed to investigate its thermomechanical behavior and the mechanisms for the observed phenomena during the actuation cycles, and to provide insight into how to improve the design. (paper)

  19. Quantum memory for Rindler supertranslations

    Science.gov (United States)

    Kolekar, Sanved; Louko, Jorma

    2018-04-01

    The Rindler horizon in Minkowski spacetime can be implanted with supertranslation hair by a matter shock wave without planar symmetry, and the hair is observable as a supertranslation memory on the Rindler family of uniformly linearly accelerated observers. We show that this classical memory is accompanied by a supertranslation quantum memory that modulates the entanglement between the opposing Rindler wedges in quantum field theory. A corresponding phenomenon across a black hole horizon may play a role in Hawking, Perry, and Strominger's proposal for supertranslations to provide a solution to the black hole information paradox.

  20. Atomic excitation and recombination in external fields

    International Nuclear Information System (INIS)

    Nayfeh, M.H.; Clark, C.W.

    1985-01-01

    This volume offers a timely look at Rydberg states of atoms in external fields and dielectronic recombination. Each topic provides authoritative coverage, presents a fresh account of a flourishing field of current atomic physics and introduces new opportunities for discovery and development. Topics considered include electron-atom scattering in external fields; observations of regular and irregular motion as exemplified by the quadratic zeeman effect and other systems; Rydberg atoms in external fields and the Coulomb geometry; crossed-field effects in the absorption spectrum of lithium in a magnetic field; precise studies of static electric field ionization; widths and shapes of stark resonances in sodium above the saddle point; studies of electric field effects and barium autoionizing resonances; autoionization and dielectronic recombination in plasma electric microfields; dielectronic recombination measurements on multicharged ions; merged beam studies of dielectronic recombination; Rydberg atoms and dielectronic recombination in astrophysics; and observations on dielectronic recombination

  1. Influence of memory theme and posttraumatic stress disorder on memory specificity in British and Iranian trauma survivors.

    Science.gov (United States)

    Jobson, Laura; Cheraghi, Sepideh

    2016-09-01

    This study investigated the influence of culture, memory theme and posttraumatic stress disorder (PTSD) on autobiographical memory specificity in Iranian and British trauma survivors. Participants completed the Autobiographical Memory Test and PTSD Diagnostic Scale. The results indicated that the British group provided significantly more personal-themed memories than the Iranian group, while the Iranian group provided significantly more social-themed memories than the British group. The British group also provided a significantly greater proportion of specific personal-themed and social-themed memories than the Iranian group. Overall, in both cultural groups memory specificity was found to be significantly correlated with PTSD symptoms. These findings provide further evidence that regardless of memory theme, specificity of autobiographical memories function to differentiate the self from others and reaffirm the independent self. They also further highlight that pan-culturally an overgeneral retrieval style may be employed by those with PTSD symptoms.

  2. How Fuzzy-Trace Theory Predicts True and False Memories for Words, Sentences, and Narratives

    OpenAIRE

    Reyna, Valerie F.; Corbin, Jonathan C.; Weldon, Rebecca B.; Brainerd, Charles J.

    2016-01-01

    Fuzzy-trace theory posits independent verbatim and gist memory processes, a distinction that has implications for such applied topics as eyewitness testimony. This distinction between precise, literal verbatim memory and meaning-based, intuitive gist accounts for memory paradoxes including dissociations between true and false memory, false memories outlasting true memories, and developmental increases in false memory. We provide an overview of fuzzy-trace theory, and, using mathematical model...

  3. Concrete Memories

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2015-01-01

    This article traces the presence of Atlantikwall bunkers in amateur holiday snapshots and discusses the ambiguous role of the bunker site in visual cultural memory. Departing from my family’s private photo collection from twenty years of vacationing at the Danish West coast, the different mundane...... and poetic appropriations and inscriptions of the bunker site are depicted. Ranging between overlooked side presences and an overwhelming visibility, the concrete remains of fascist war architecture are involved in and motivate different sensuous experiences and mnemonic appropriations. The article meets...... the bunkers’ changing visuality and the cultural topography they both actively transform and are being transformed by through juxtaposing different acts and objects of memory over time and in different visual articulations....

  4. Episodic Memory: A Comparative Approach

    Science.gov (United States)

    Martin-Ordas, Gema; Call, Josep

    2013-01-01

    Historically, episodic memory has been described as autonoetic, personally relevant, complex, context-rich, and allowing mental time travel. In contrast, semantic memory, which is theorized to be free of context and personal relevance, is noetic and consists of general knowledge of facts about the world. The field of comparative psychology has adopted this distinction in order to study episodic memory in non-human animals. Our aim in this article is not only to reflect on the concept of episodic memory and the experimental approaches used in comparative psychology to study this phenomenon, but also to provide a critical analysis of these paradigms. We conclude the article by providing new avenues for future research. PMID:23781179

  5. Controlled transport of solitons and bubbles using external perturbations

    International Nuclear Information System (INIS)

    Gonzalez, J.A.; Marcano, A.; Mello, B.A.; Trujillo, L.

    2006-01-01

    We investigate generalized soliton-bearing systems in the presence of external perturbations. We show the possibility of the transport of solitons using external waves, provided the waveform and its velocity satisfy certain conditions. We also investigate the stabilization and transport of bubbles using external perturbations in 3D-systems. We also present the results of real experiments with laser-induced vapor bubbles in liquids

  6. Treadwell Memorial

    OpenAIRE

    Downey, Frances K

    2015-01-01

    This is a memorial to gold mining in Southeast Alaska. The structure takes visitors from the Treadwell trail onto the edge of a popular local beach, reclaiming a forgotten place that was once the largest gold mine in the world. A tangible tribute to this obscure period of history, this building kindles a connection between artifacts and the community. It is a liminal space, connecting ocean and mountain, past and present, civilization and wilderness. An investigation of the Treadwell Gold...

  7. Methods, apparatus and system for notification of predictable memory failure

    Energy Technology Data Exchange (ETDEWEB)

    Cher, Chen-Yong; Andrade Costa, Carlos H.; Park, Yoonho; Rosenburg, Bryan S.; Ryu, Kyung D.

    2017-01-03

    A method for providing notification of a predictable memory failure includes the steps of: obtaining information regarding at least one condition associated with a memory; calculating a memory failure probability as a function of the obtained information; calculating a failure probability threshold; and generating a signal when the memory failure probability exceeds the failure probability threshold, the signal being indicative of a predicted future memory failure.

  8. External costs of nuclear-generated electricity

    International Nuclear Information System (INIS)

    Rotaru, I.; Glodeanu, F.; Popescu, D.; Andrei, V.

    2004-01-01

    External costs of nuclear power include: future financial liabilities arising from decommissioning and dismantling of nuclear facilities, health and environmental impacts of radioactivity releases in routine operation, radioactive waste disposal and effects of severe accidents. The nuclear energy industry operates under regulations that impose stringent limits to atmospheric emissions and liquid effluents from nuclear facilities as well as requiring the containment and confinement of solid radioactive waste to ensure its isolation from the biosphere as long as it may be harmful for human health and the environment. The capital and operating costs of nuclear power plants and fuel cycle facilities already internalize a major portion of the above-mentioned potential external costs, and these are reflected in the prices paid by consumers of nuclear-generated electricity. The externality related to potential health and environmental impacts of radioactive releases during routine operations have been assessed in a large number of comprehensive studies, in particular the ExternE project that was created in the framework of the European Commission. With regard to effects of severe nuclear accidents, a special legal regime, the third-party liability system, has been implemented to provide limited third party liability coverage in the event of a nuclear accident. The nuclear plant owners are held liable for some specified first substantial part of damages to third parties, and must secure insurance coverage adequate to cover this part. The Government provides coverage for some specified substantial second part of the damages, with any remaining damages to be considered by the national legislation. Thus, the costs of an incident or accident are fully internalized in the costs borne by the nuclear plant owners. Externalities of energy are not limited to environmental and health related impacts, but may result also from macro-economic, policy or strategic factors not reflected

  9. Working memory predicts the rejection of false memories.

    Science.gov (United States)

    Leding, Juliana K

    2012-01-01

    The relationship between working memory capacity (WMC) and false memories in the memory conjunction paradigm was explored. Previous research using other paradigms has shown that individuals high in WMC are not as likely to experience false memories as low-WMC individuals, the explanation being that high-WMC individuals are better able to engage in source monitoring. In the memory conjunction paradigm participants are presented at study with parent words (e.g., eyeglasses, whiplash). At test, in addition to being presented with targets and foils, participants are presented with lures that are composed of previously studied features (e.g., eyelash). It was found that high-WMC individuals had lower levels of false recognition than low-WMC individuals. Furthermore, recall-to-reject responses were analysed (e.g., "I know I didn't see eyelash because I remember seeing eyeglasses") and it was found that high-WMC individuals were more likely to utilise this memory editing strategy, providing direct evidence that one reason that high-WMC individuals are not as prone to false memories is because they are better able to engage in source monitoring.

  10. Skin-Inspired Haptic Memory Arrays with an Electrically Reconfigurable Architecture.

    Science.gov (United States)

    Zhu, Bowen; Wang, Hong; Liu, Yaqing; Qi, Dianpeng; Liu, Zhiyuan; Wang, Hua; Yu, Jiancan; Sherburne, Matthew; Wang, Zhaohui; Chen, Xiaodong

    2016-02-24

    Skin-inspired haptic-memory devices, which can retain pressure information after the removel of external pressure by virtue of the nonvolatile nature of the memory devices, are achieved. The rise of haptic-memory devices will allow for mimicry of human sensory memory, opening new avenues for the design of next-generation high-performance sensing devices and systems. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. A simplified memory network model based on pattern formations

    Science.gov (United States)

    Xu, Kesheng; Zhang, Xiyun; Wang, Chaoqing; Liu, Zonghua

    2014-12-01

    Many experiments have evidenced the transition with different time scales from short-term memory (STM) to long-term memory (LTM) in mammalian brains, while its theoretical understanding is still under debate. To understand its underlying mechanism, it has recently been shown that it is possible to have a long-period rhythmic synchronous firing in a scale-free network, provided the existence of both the high-degree hubs and the loops formed by low-degree nodes. We here present a simplified memory network model to show that the self-sustained synchronous firing can be observed even without these two necessary conditions. This simplified network consists of two loops of coupled excitable neurons with different synaptic conductance and with one node being the sensory neuron to receive an external stimulus signal. This model can be further used to show how the diversity of firing patterns can be selectively formed by varying the signal frequency, duration of the stimulus and network topology, which corresponds to the patterns of STM and LTM with different time scales. A theoretical analysis is presented to explain the underlying mechanism of firing patterns.

  12. The path to epigenetic treatment of memory disorders.

    Science.gov (United States)

    Mikaelsson, Mikael A; Miller, Courtney A

    2011-07-01

    A new line of neuroscience research suggests that epigenetics may be the site of nature and nurture integration by providing the environment with a mechanism to directly influence the read-out of our genome. Epigenetic mechanisms in the brain are a series of post-translational chromatin and DNA modifications driven by external input. Given the critical hub that epigenetics appears to be, neuroscientists have come to suspect its fundamental influence on how our minds change in response to our unique environment and, in turn, how these changes can then impact our future interactions with the environment. The field of learning and memory is becoming particularly interested in understanding the cognitive influence of epigenetics. With the majority of us working with an eye toward therapeutics, the question naturally arises: "Has neuroepigenetics gotten us closer to treating memory disorders and if so, where do we go from here?" This review will begin with a brief exploration of recent advances in our understanding of how epigenetic mechanisms contribute to learning and memory processes that are susceptible to failure. Next the implications for disorders of cognition, such as Alzheimer's disease, will be discussed. Finally, we will use parallels from the field of cancer to speculate on where we should consider heading from here in the pursuit of therapeutics. Published by Elsevier Inc.

  13. High spatial resolution infrared camera as ISS external experiment

    Science.gov (United States)

    Eckehard, Lorenz; Frerker, Hap; Fitch, Robert Alan

    High spatial resolution infrared camera as ISS external experiment for monitoring global climate changes uses ISS internal and external resources (eg. data storage). The optical experiment will consist of an infrared camera for monitoring global climate changes from the ISS. This technology was evaluated by the German small satellite mission BIRD and further developed in different ESA projects. Compared to BIRD the presended instrument uses proven sensor advanced technologies (ISS external) and ISS on board processing and storage capabili-ties (internal). The instrument will be equipped with a serial interfaces for TM/TC and several relay commands for the power supply. For data processing and storage a mass memory is re-quired. The access to actual attitude data is highly desired to produce geo referenced maps-if possible by an on board processing.

  14. Decision theory, motor planning, and visual memory: deciding where to reach when memory errors are costly.

    Science.gov (United States)

    Lerch, Rachel A; Sims, Chris R

    2016-06-01

    Limitations in visual working memory (VWM) have been extensively studied in psychophysical tasks, but not well understood in terms of how these memory limits translate to performance in more natural domains. For example, in reaching to grasp an object based on a spatial memory representation, overshooting the intended target may be more costly than undershooting, such as when reaching for a cup of hot coffee. The current body of literature lacks a detailed account of how the costs or consequences of memory error influence what we encode in visual memory and how we act on the basis of remembered information. Here, we study how externally imposed monetary costs influence behavior in a motor decision task that involves reach planning based on recalled information from VWM. We approach this from a decision theoretic perspective, viewing decisions of where to aim in relation to the utility of their outcomes given the uncertainty of memory representations. Our results indicate that subjects accounted for the uncertainty in their visual memory, showing a significant difference in their reach planning when monetary costs were imposed for memory errors. However, our findings indicate that subjects memory representations per se were not biased by the imposed costs, but rather subjects adopted a near-optimal post-mnemonic decision strategy in their motor planning.

  15. Brain substrates of implicit and explicit memory: the importance of concurrently acquired neural signals of both memory types.

    Science.gov (United States)

    Voss, Joel L; Paller, Ken A

    2008-11-01

    A comprehensive understanding of human memory requires cognitive and neural descriptions of memory processes along with a conception of how memory processing drives behavioral responses and subjective experiences. One serious challenge to this endeavor is that an individual memory process is typically operative within a mix of other contemporaneous memory processes. This challenge is particularly disquieting in the context of implicit memory, which, unlike explicit memory, transpires without the subject necessarily being aware of memory retrieval. Neural correlates of implicit memory and neural correlates of explicit memory are often investigated in different experiments using very different memory tests and procedures. This strategy poses difficulties for elucidating the interactions between the two types of memory process that may result in explicit remembering, and for determining the extent to which certain neural processing events uniquely contribute to only one type of memory. We review recent studies that have succeeded in separately assessing neural correlates of both implicit memory and explicit memory within the same paradigm using event-related brain potentials (ERPs) and functional magnetic resonance imaging (fMRI), with an emphasis on studies from our laboratory. The strategies we describe provide a methodological framework for achieving valid assessments of memory processing, and the findings support an emerging conceptualization of the distinct neurocognitive events responsible for implicit and explicit memory.

  16. Distributed learning enhances relational memory consolidation.

    Science.gov (United States)

    Litman, Leib; Davachi, Lila

    2008-09-01

    It has long been known that distributed learning (DL) provides a mnemonic advantage over massed learning (ML). However, the underlying mechanisms that drive this robust mnemonic effect remain largely unknown. In two experiments, we show that DL across a 24 hr interval does not enhance immediate memory performance but instead slows the rate of forgetting relative to ML. Furthermore, we demonstrate that this savings in forgetting is specific to relational, but not item, memory. In the context of extant theories and knowledge of memory consolidation, these results suggest that an important mechanism underlying the mnemonic benefit of DL is enhanced memory consolidation. We speculate that synaptic strengthening mechanisms supporting long-term memory consolidation may be differentially mediated by the spacing of memory reactivation. These findings have broad implications for the scientific study of episodic memory consolidation and, more generally, for educational curriculum development and policy.

  17. Extending Mondrian Memory Protection

    Science.gov (United States)

    2010-11-01

    a kernel semaphore is locked or unlocked. In addition, we extended the system call interface to receive notifications about user-land locking...operations (such as calls to the mutex and semaphore code provided by the C library). By patching the dynamically loadable GLibC5, we are able to test... semaphores , and spinlocks. RTO-MP-IST-091 10- 9 Extending Mondrian Memory Protection to loading extension plugins. This prevents any untrusted code

  18. Social influence and mental routes to the production of authentic false memories and inauthentic false memories.

    Science.gov (United States)

    Wagner, Michael F; Skowronski, John J

    2017-05-01

    Two studies assessed the extent to which people incorporated false facts provided by bogus others into their own recognition memory reports, and how these false memory reports were affected by: (a) truth of the information in others' summaries supporting the false facts, (b) motivation to process stories and summaries, (c) source credibility, and (d) ease of remembering original facts. False memory report frequency increased when false facts in a summary were supported by true information and varied inversely with the ease with which original facts could be remembered. Results from a measure probing participants' memory perceptions suggest that some false memories are authentic: People sometimes lack awareness of both the incorporation of false facts into their memory reports and where the false facts came from. However, many false memories are inauthentic: Despite reporting a false memory, people sometimes retain knowledge of the original stimulus and/or the origin of false facts. Copyright © 2017. Published by Elsevier Inc.

  19. Improving everyday memory performance after acquired brain injury: An RCT on recollection and working memory training.

    Science.gov (United States)

    Richter, Kim Merle; Mödden, Claudia; Eling, Paul; Hildebrandt, Helmut

    2018-04-26

    To show the effectiveness of a combined recognition and working memory training on everyday memory performance in patients suffering from organic memory disorders. In this double-blind, randomized controlled Study 36 patients with organic memory impairments, mainly attributable to stroke, were assigned to either the experimental or the active control group. In the experimental group a working memory training was combined with a recollection training based on the repetition-lag procedure. Patients in the active control group received the memory therapy usually provided in the rehabilitation center. Both groups received nine hours of therapy. Prior (T0) and subsequent (T1) to the therapy, patients were evaluated on an everyday memory test (EMT) as well as on a neuropsychological test battery. Based on factor analysis of the neuropsychological test scores at T0 we calculated composite scores for working memory, verbal learning and word fluency. After treatment, the intervention group showed a significantly greater improvement for WM performance compared with the active control group. More importantly, performance on the EMT also improved significantly in patients receiving the recollection and working memory training compared with patients with standard memory training. Our results show that combining working memory and recollection training significantly improves performance on everyday memory tasks, demonstrating far transfer effects. The present study argues in favor of a process-based approach for treating memory impairments. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  20. Synaptic Correlates of Working Memory Capacity.

    Science.gov (United States)

    Mi, Yuanyuan; Katkov, Mikhail; Tsodyks, Misha

    2017-01-18

    Psychological studies indicate that human ability to keep information in readily accessible working memory is limited to four items for most people. This extremely low capacity severely limits execution of many cognitive tasks, but its neuronal underpinnings remain unclear. Here we show that in the framework of synaptic theory of working memory, capacity can be analytically estimated to scale with characteristic time of short-term synaptic depression relative to synaptic current time constant. The number of items in working memory can be regulated by external excitation, enabling the system to be tuned to the desired load and to clear the working memory of currently held items to make room for new ones. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. External coating of colonic anastomoses

    DEFF Research Database (Denmark)

    Pommergaard, Hans-Christian; Achiam, Michael Patrick; Rosenberg, Jacob

    2012-01-01

    Colon anastomotic leakage remains both a frequent and serious complication in gastrointestinal surgery. External coating of colonic anastomoses has been proposed as a means to lower the rate of this complication. The aim of this review was to evaluate existing studies on external coating of colonic...

  2. Retrofitting Systems for External Walls

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report, 9 different external and internal retrofitting systems are analyzed using numerical calculations. The analysis focuses on the thermal bridge effects in the different systems, and on this basis it is discussed whether internal or external retrofitting has the most advantages...

  3. How does the sparse memory "engram" neurons encode the memory of a spatial-temporal event?

    Directory of Open Access Journals (Sweden)

    Ji-Song Guan

    2016-08-01

    Full Text Available Episodic memory in human brain is not a fixed 2-D picture but a highly dynamic movie serial, integrating information at both the temporal and the spatial domains. Recent studies in neuroscience reveal that memory storage and recall are closely related to the activities in discrete memory engram (trace neurons within the dentate gyrus region of hippocampus and the layer 2/3 of neocortex. More strikingly, optogenetic reactivation of those memory trace neurons is able to trigger the recall of naturally encoded memory. It is still unknown how the discrete memory traces encode and reactivate the memory. Considering a particular memory normally represents a natural event, which consists of information at both the temporal and spatial domains, it is unknown how the discrete trace neurons could reconstitute such enriched information in the brain. Furthermore, as the optogenetic-stimuli induced recall of memory did not depend on firing pattern of the memory traces, it is most likely that the spatial activation pattern, but not the temporal activation pattern of the discrete memory trace neurons encodes the memory in the brain. How does the neural circuit convert the activities in the spatial domain into the temporal domain to reconstitute memory of a natural event? By reviewing the literature, here we present how the memory engram (trace neurons are selected and consolidated in the brain. Then, we will discuss the main challenges in the memory trace theory. In the end, we will provide a plausible model of memory trace cell network, underlying the conversion of neural activities between the spatial domain and the temporal domain. We will also discuss on how the activation of sparse memory trace neurons might trigger the replay of neural activities in specific temporal patterns.

  4. Accessing external innovation in drug discovery and development.

    Science.gov (United States)

    Tufféry, Pierre

    2015-06-01

    A decline in the productivity of the pharmaceutical industry research and development (R&D) pipeline has highlighted the need to reconsider the classical strategies of drug discovery and development, which are based on internal resources, and to identify new means to improve the drug discovery process. Accepting that the combination of internal and external ideas can improve innovation, ways to access external innovation, that is, opening projects to external contributions, have recently been sought. In this review, the authors look at a number of external innovation opportunities. These include increased interactions with academia via academic centers of excellence/innovation centers, better communication on projects using crowdsourcing or social media and new models centered on external providers such as built-to-buy startups or virtual pharmaceutical companies. The buzz for accessing external innovation relies on the pharmaceutical industry's major challenge to improve R&D productivity, a conjuncture favorable to increase interactions with academia and new business models supporting access to external innovation. So far, access to external innovation has mostly been considered during early stages of drug development, and there is room for enhancement. First outcomes suggest that external innovation should become part of drug development in the long term. However, the balance between internal and external developments in drug discovery can vary largely depending on the company strategies.

  5. Externalities of fuel cycles 'ExternE' project. Economic valuation. Economical valuation: An impact pathway approach

    International Nuclear Information System (INIS)

    Markandya, A.

    1994-01-01

    European literature as was feasible has been carried out, such a survey is certain to fall short of reviewing the full literature simply because the larger part of it is North American. The latter was being reviewed separately by the US team. However, in making recommendations as to what valuation methods or studies to use, the report draws on the substantial US experience. The whole issue of when a methodology or a particular study can be transferred from one context to another has never been fully addressed. This report makes some suggestions as to when this is may be appropriate although it is recognized that this is by no means a definitive discussion of that issue. Certainly, the fact that the fuel cycle analysis here is location-specific, rather than 'generic', in the sense of providing broad average costs of impacts caused by the use of certain fuels, makes the transferability of estimates more difficult. The report is structured as follows. Part I begins with a discussion of the nature of externalities and a more precise definition of what is being measured. Of particular importance in this context is the extent to which an environmental impact is or is not an 'externality'. Without going into the more complex aspects of the economic theory, the report offers some advice on when the issue is relevant and what criteria might be used to assess whether or not a particular environmental impact really is an externality. The remainder of Part I then deals with a number of general issues that are of practical importance in the context of valuing specific impacts. These are: the question of transferability discussed above; the time period or timescale over which the valuation is to take place; the treatment of uncertainty; the discounting of future costs; and the finally the issue of exactly what is being assumed constant when a particular valuation is being carried out. This is of special significance in the context of the valuation being undertaken here. Part II of the

  6. Conventional external beam radiotherapy for central nervous system malignancies

    International Nuclear Information System (INIS)

    Halperin, E.C.; Burger, P.C.

    1985-01-01

    Fractionated external beam photon radiotherapy is an important component of the clinical management of malignant disease of the central nervous system. The practicing neurologist or neurosurgeon frequently relies on the consultative and treatment skills of a radiotherapist. This article provides a review for the nonradiotherapist of the place of conventional external beam radiotherapy in neuro-oncology. 23 references

  7. Neural bases of prospective memory: a meta-analysis and the "Attention to Delayed Intention" (AtoDI) model.

    Science.gov (United States)

    Cona, Giorgia; Scarpazza, Cristina; Sartori, Giuseppe; Moscovitch, Morris; Bisiacchi, Patrizia Silvia

    2015-05-01

    Remembering to realize delayed intentions is a multi-phase process, labelled as prospective memory (PM), and involves a plurality of neural networks. The present study utilized the activation likelihood estimation method of meta-analysis to provide a complete overview of the brain regions that are consistently activated in each PM phase. We formulated the 'Attention to Delayed Intention' (AtoDI) model to explain the neural dissociation found between intention maintenance and retrieval phases. The dorsal frontoparietal network is involved mainly in the maintenance phase and seems to mediate the strategic monitoring processes, such as the allocation of top-down attention both towards external stimuli, to monitor for the occurrence of the PM cues, and to internal memory contents, to maintain the intention active in memory. The ventral frontoparietal network is recruited in the retrieval phase and might subserve the bottom-up attention captured externally by the PM cues and, internally, by the intention stored in memory. Together with other brain regions (i.e., insula and posterior cingulate cortex), the ventral frontoparietal network would support the spontaneous retrieval processes. The functional contribution of the anterior prefrontal cortex is discussed extensively for each PM phase. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Large capacity temporary visual memory

    Science.gov (United States)

    Endress, Ansgar D.; Potter, Mary C.

    2014-01-01

    Visual working memory (WM) capacity is thought to be limited to three or four items. However, many cognitive activities seem to require larger temporary memory stores. Here, we provide evidence for a temporary memory store with much larger capacity than past WM capacity estimates. Further, based on previous WM research, we show that a single factor — proactive interference — is sufficient to bring capacity estimates down to the range of previous WM capacity estimates. Participants saw a rapid serial visual presentation (RSVP) of 5 to 21 pictures of familiar objects or words presented at rates of 4/s or 8/s, respectively, and thus too fast for strategies such as rehearsal. Recognition memory was tested with a single probe item. When new items were used on all trials, no fixed memory capacities were observed, with estimates of up to 9.1 retained pictures for 21-item lists, and up to 30.0 retained pictures for 100-item lists, and no clear upper bound to how many items could be retained. Further, memory items were not stored in a temporally stable form of memory, but decayed almost completely after a few minutes. In contrast, when, as in most WM experiments, a small set of items was reused across all trials, thus creating proactive interference among items, capacity remained in the range reported in previous WM experiments. These results show that humans have a large-capacity temporary memory store in the absence of proactive interference, and raise the question of whether temporary memory in everyday cognitive processing is severely limited as in WM experiments, or has the much larger capacity found in the present experiments. PMID:23937181

  9. Relevance of quality of life assessment for multiple sclerosis patients with memory impairment.

    Directory of Open Access Journals (Sweden)

    Karine Baumstarck

    Full Text Available BACKGROUND: Memory disturbances, in particular episodic verbal memory dysfunction, are the most frequent cognitive impairment observed in multiple sclerosis (MS patients. The use of self-reported outcomes for evaluating treatment and managing care of these subjects has been questioned. The aim of this study was to provide new evidence about the suitability of self-reported outcomes for use in this impaired population by exploring the internal structure, reliability and external validity of a specific quality of life (QoL instrument, the Multiple Sclerosis International Quality of Life questionnaire (MusiQoL. METHODS: DESIGN: cross-sectional study. INCLUSION CRITERIA: MS patients of any disease subtype. DATA COLLECTION: sociodemographic (age, gender, marital status, education level, and occupational activity and clinical data (MS subtype, Expanded Disability Status Scale, disease duration; QoL (MusiQoL and SF36; and memory performance (Grober and Buschke test. In accordance with the French norms of the memory test, non-impaired and impaired populations were defined for short- and long-delay free composites and for short- and long-delay total composites. For the 8 populations, psychometric properties were compared to those reported from the reference population assessed in the validation study. PRINCIPAL FINDINGS: One hundred and twenty-four consecutive patients were enrolled. The analysis performed in the impaired populations showed that the questionnaire structure adequately matched the initial structure of the MusiQoL. The unidimensionality of the dimensions was preserved, and the internal/external validity indices were close to those of the reference population. CONCLUSIONS/SIGNIFICANCE: Our study suggests that memory dysfunction did not compromise the reliability or validity of the self-reported QoL questionnaires.

  10. Dissociation between source and item memory in Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Hu Panpan; Li Youhai; Ma Huijuan; Xi Chunhua; Chen Xianwen; Wang Kai

    2014-01-01

    Background Episodic memory includes information about item memory and source memory.Many researches support the hypothesis that these two memory systems are implemented by different brain structures.The aim of this study was to investigate the characteristics of item memory and source memory processing in patients with Parkinson's disease (PD),and to further verify the hypothesis of dual-process model of source and item memory.Methods We established a neuropsychological battery to measure the performance of item memory and source memory.Totally 35 PD individuals and 35 matched healthy controls (HC) were administrated with the battery.Item memory task consists of the learning and recognition of high-frequency national Chinese characters; source memory task consists of the learning and recognition of three modes (character,picture,and image) of objects.Results Compared with the controls,the idiopathic PD patients have been impaired source memory (PD vs.HC:0.65±0.06 vs.0.72±0.09,P=0.001),but not impaired in item memory (PD vs.HC:0.65±0.07 vs.0.67±0.08,P=0.240).Conclusions The present experiment provides evidence for dissociation between item and source memory in PD patients,thereby strengthening the claim that the item or source memory rely on different brain structures.PD patients show poor source memory,in which dopamine plays a critical role.

  11. Externalising the autobiographical self: sharing personal memories online facilitated memory retention.

    Science.gov (United States)

    Wang, Qi; Lee, Dasom; Hou, Yubo

    2017-07-01

    Internet technology provides a new means of recalling and sharing personal memories in the digital age. What is the mnemonic consequence of posting personal memories online? Theories of transactive memory and autobiographical memory would make contrasting predictions. In the present study, college students completed a daily diary for a week, listing at the end of each day all the events that happened to them on that day. They also reported whether they posted any of the events online. Participants received a surprise memory test after the completion of the diary recording and then another test a week later. At both tests, events posted online were significantly more likely than those not posted online to be recalled. It appears that sharing memories online may provide unique opportunities for rehearsal and meaning-making that facilitate memory retention.

  12. Making lasting memories: Remembering the significant

    Science.gov (United States)

    McGaugh, James L.

    2013-01-01

    Although forgetting is the common fate of most of our experiences, much evidence indicates that emotional arousal enhances the storage of memories, thus serving to create, selectively, lasting memories of our more important experiences. The neurobiological systems mediating emotional arousal and memory are very closely linked. The adrenal stress hormones epinephrine and corticosterone released by emotional arousal regulate the consolidation of long-term memory. The amygdala plays a critical role in mediating these stress hormone influences. The release of norepinephrine in the amygdala and the activation of noradrenergic receptors are essential for stress hormone-induced memory enhancement. The findings of both animal and human studies provide compelling evidence that stress-induced activation of the amygdala and its interactions with other brain regions involved in processing memory play a critical role in ensuring that emotionally significant experiences are well-remembered. Recent research has determined that some human subjects have highly superior autobiographic memory of their daily experiences and that there are structural differences in the brains of these subjects compared with the brains of subjects who do not have such memory. Understanding of neurobiological bases of such exceptional memory may provide additional insights into the processes underlying the selectivity of memory. PMID:23754441

  13. Sensory memory for ambiguous vision.

    Science.gov (United States)

    Pearson, Joel; Brascamp, Jan

    2008-09-01

    In recent years the overlap between visual perception and memory has shed light on our understanding of both. When ambiguous images that normally cause perception to waver unpredictably are presented briefly with intervening blank periods, perception tends to freeze, locking into one interpretation. This indicates that there is a form of memory storage across the blank interval. This memory trace codes low-level characteristics of the stored stimulus. Although a trace is evident after a single perceptual instance, the trace builds over many separate stimulus presentations, indicating a flexible, variable-length time-course. This memory shares important characteristics with priming by non-ambiguous stimuli. Computational models now provide a framework to interpret many empirical observations.

  14. Visual working memory contaminates perception.

    Science.gov (United States)

    Kang, Min-Suk; Hong, Sang Wook; Blake, Randolph; Woodman, Geoffrey F

    2011-10-01

    Indirect evidence suggests that the contents of visual working memory may be maintained within sensory areas early in the visual hierarchy. We tested this possibility using a well-studied motion repulsion phenomenon in which perception of one direction of motion is distorted when another direction of motion is viewed simultaneously. We found that observers misperceived the actual direction of motion of a single motion stimulus if, while viewing that stimulus, they were holding a different motion direction in visual working memory. Control experiments showed that none of a variety of alternative explanations could account for this repulsion effect induced by working memory. Our findings provide compelling evidence that visual working memory representations directly interact with the same neural mechanisms as those involved in processing basic sensory events.

  15. Intentionally fabricated autobiographical memories

    OpenAIRE

    Justice, LV; Morrison, CM; Conway, MA

    2017-01-01

    Participants generated both autobiographical memories (AMs) that they believed to be true and intentionally fabricated autobiographical memories (IFAMs). Memories were constructed while a concurrent memory load (random 8-digit sequence) was held in mind or while there was no concurrent load. Amount and accuracy of recall of the concurrent memory load was reliably poorer following generation of IFAMs than following generation of AMs. There was no reliable effect of load on memory generation ti...

  16. STRUKTUR DAN PROSES MEMORI

    Directory of Open Access Journals (Sweden)

    Magda Bhinnety

    2015-09-01

    Full Text Available This paper describes structures and processes of human memory system according to the modal model. Sensory memory is described as the first system to store information from outside world. Short‐term memory, or now called working memory, represents a system characterized by limited ability in storing as well as retrieving information. Long‐term memory on the hand stores information larger in amount and longer than short‐term memory

  17. STRUKTUR DAN PROSES MEMORI

    OpenAIRE

    Bhinnety, Magda

    2015-01-01

    This paper describes structures and processes of human memory system according to the modal model. Sensory memory is described as the first system to store information from outside world. Short‐term memory, or now called working memory, represents a system characterized by limited ability in storing as well as retrieving information. Long‐term memory on the hand stores information larger in amount and longer than short‐term memory

  18. The Structure of Human Memory. Technical Report No. 321.

    Science.gov (United States)

    Brewer, William F.; Pani, John R.

    The four sections of this paper provide an analysis of the structure of human memory. The first section, intended to provide a clear example of personal memory, examines a hypothetical episode in the life of an undergraduate student, and shows how one episode can give rise to three different forms of memory: personal, semantic, and rote…

  19. Shape memory system with integrated actuation using embedded particles

    Science.gov (United States)

    Buckley, Patrick R [New York, NY; Maitland, Duncan J [Pleasant Hill, CA

    2009-09-22

    A shape memory material with integrated actuation using embedded particles. One embodiment provides a shape memory material apparatus comprising a shape memory material body and magnetic pieces in the shape memory material body. Another embodiment provides a method of actuating a device to perform an activity on a subject comprising the steps of positioning a shape memory material body in a desired position with regard to the subject, the shape memory material body capable of being formed in a specific primary shape, reformed into a secondary stable shape, and controllably actuated to recover the specific primary shape; including pieces in the shape memory material body; and actuating the shape memory material body using the pieces causing the shape memory material body to be controllably actuated to recover the specific primary shape and perform the activity on the subject.

  20. External costs related to power production technologies. ExternE national implementation for Denmark

    International Nuclear Information System (INIS)

    Schleisner, L.; Sieverts Nielsen, P.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results; to aggregate these site- and technology-specific results to more general figures. The current report covers the results of the national implementation for Denmark. Three different fuel cycles have been chosen as case studies. These are fuel cycles for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant based on biogas. The report covers all the details of the application of the methodology to these fuel cycles aggregation to a national level. (au) EU-JOULE 3. 59 tabs., 25 ills., 61 refs

  1. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L; Sieverts Nielsen, P

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results; to aggregate these site- and technology-specific results to more general figures. The current report covers the results of the national implementation for Denmark. Three different fuel cycles have been chosen as case studies. These are fuel cycles for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant based on biogas. The report covers all the details of the application of the methodology to these fuel cycles aggregation to a national level. (au) EU-JOULE 3. 59 tabs., 25 ills., 61 refs.

  2. Electroconvulsive therapy and memory.

    Science.gov (United States)

    Harper, R G; Wiens, A N

    1975-10-01

    Recent research on the effects of electroconvulsive therapy (ECT) on memory is critically reviewed. Despite some inconsistent findings, unilateral nondominant ECT appears to affect verbal memory less than bilateral ECT. Adequate research on multiple monitored ECT is lacking. With few exceptions, the research methodologies for assessing memory have been inadequate. Many studies have confounded learning with retention, and only very recently has long term memory been adequately studied. Standardized assessment procedures for short term and long term memory are needed, in addition to more sophisticated assessment of memory processes, the duration of memory loss, and qualitative aspects of memories.

  3. Autobiographical thinking interferes with episodic memory consolidation.

    Directory of Open Access Journals (Sweden)

    Michael Craig

    Full Text Available New episodic memories are retained better if learning is followed by a few minutes of wakeful rest than by the encoding of novel external information. Novel encoding is said to interfere with the consolidation of recently acquired episodic memories. Here we report four experiments in which we examined whether autobiographical thinking, i.e. an 'internal' memory activity, also interferes with episodic memory consolidation. Participants were presented with three wordlists consisting of common nouns; one list was followed by wakeful rest, one by novel picture encoding and one by autobiographical retrieval/future imagination, cued by concrete sounds. Both novel encoding and autobiographical retrieval/future imagination lowered wordlist retention significantly. Follow-up experiments demonstrated that the interference by our cued autobiographical retrieval/future imagination delay condition could not be accounted for by the sound cues alone or by executive retrieval processes. Moreover, our results demonstrated evidence of a temporal gradient of interference across experiments. Thus, we propose that rich autobiographical retrieval/future imagination hampers the consolidation of recently acquired episodic memories and that such interference is particularly likely in the presence of external concrete cues.

  4. High-Temperature Shape Memory Polymers

    Science.gov (United States)

    Yoonessi, Mitra; Weiss, Robert A.

    2012-01-01

    physical conformation changes when exposed to an external stimulus, such as a change in temperature. Such materials have a permanent shape, but can be reshaped above a critical temperature and fixed into a temporary shape when cooled under stress to below the critical temperature. When reheated above the critical temperature (Tc, also sometimes called the triggering or switching temperature), the materials revert to the permanent shape. The current innovation involves a chemically treated (sulfonated, carboxylated, phosphonated, or other polar function group), high-temperature, semicrystalline thermoplastic poly(ether ether ketone) (Tg .140 C, Tm = 340 C) mix containing organometallic complexes (Zn++, Li+, or other metal, ammonium, or phosphonium salts), or high-temperature ionic liquids (e.g. hexafluorosilicate salt with 1-propyl-3- methyl imidazolium, Tm = 210 C) to form a network where dipolar or ionic interactions between the polymer and the low-molecular-weight or inorganic compound forms a complex that provides a physical crosslink. Hereafter, these compounds will be referred to as "additives". The polymer is semicrystalline, and the high-melt-point crystals provide a temporary crosslink that acts as a permanent crosslink just so long as the melting temperature is not exceeded. In this example case, the melting point is .340 C, and the shape memory critical temperature is between 150 and 250 C. PEEK is an engineering thermoplastic with a high Young fs modulus, nominally 3.6 GPa. An important aspect of the invention is the control of the PEEK functionalization (in this example, the sulfonation degree), and the thermal properties (i.e. melting point) of the additive, which determines the switching temperature. Because the compound is thermoplastic, it can be formed into the "permanent" shape by conventional plastics processing operations. In addition, the compound may be covalently cross - linked after forming the permanent shape by S-PEEK by applying ionizing

  5. External effects in Swiss hydropower

    International Nuclear Information System (INIS)

    Hauenstein, W.; Bonvin, J.; Vouillamoz, J.

    1999-01-01

    The article discusses the external costs and benefits of hydropower that are not internalised in normal book-keeping. Several negative and positive effects are discussed. The results of a study that addressed the difficult task of quantifying these external effects are presented. An assessment of the results gained shows that difficulties are to be met regarding system limits, methods of expressing the effects in monetary terms and ethical factors. The report also examines the consideration of external effects as a correction factor for falsified market prices for electricity

  6. Detailed sensory memory, sloppy working memory

    NARCIS (Netherlands)

    Sligte, I.G.; Vandenbroucke, A.R.E.; Scholte, H.S.; Lamme, V.A.F.

    2010-01-01

    Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity

  7. Control of external radiation exposure

    International Nuclear Information System (INIS)

    Abd Nasir Ibrahim; Azali Muhammad; Ab Razak Hamzah; Abd Aziz Mohamed; Mohammad Pauzi Ismail

    2004-01-01

    The following subjects are discussed - Control of external radiation exposure: working time, working distance, shielding: Total Linear Attenuation Coefficient, Half-Value Layer (HVL), Tenth-Value Layer (TVL); Build-up Factor

  8. External costs related to power production technologies. ExternE national implementation for Denmark

    International Nuclear Information System (INIS)

    Schleisner, L.; Sieverts Nielsen, P.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results, to aggregate these site- and technology-specific results to more general figures. The current report covers the detailed information concerning the ExternE methodology. Importance is attached to the computer system used in the project and the assessment of air pollution effects on health, materials and ecological effects. Also the assessment of global warming damages are described. Finally the report covers the detailed information concerning the national implementation for Denmark for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant base on biogas. (au) EU-JOULE 3. 79 tabs., 11 ills., 201 refs

  9. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L; Sieverts Nielsen, P [eds.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results, to aggregate these site- and technology-specific results to more general figures. The current report covers the detailed information concerning the ExternE methodology. Importance is attached to the computer system used in the project and the assessment of air pollution effects on health, materials and ecological effects. Also the assessment of global warming damages are described. Finally the report covers the detailed information concerning the national implementation for Denmark for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant base on biogas. (au) EU-JOULE 3. 79 tabs., 11 ills., 201 refs.

  10. Externalities of energy. Swedish implementation of the ExternE methodology

    International Nuclear Information System (INIS)

    Nilsson, Maans; Gullberg, M.

    1998-01-01

    The growing interest for developing economic instruments for efficient environmental policies has opened up a large area of multi-disciplinary research. ExternE is an example of this research, combining disciplines such as engineering, ecology, immunology and economics expertise to create new knowledge about how environmental pressures from energy production affect our nature and society. The ExternE Project aims to identify and, as far as possible quantify the externalities of energy production in Europe. The Stockholm Environment Institute has carried out a preliminary aggregation: -Coal Fuel Cycle: centred around Vaesteraas Kraftvaermeverk, Vaesteraas. This is the largest co-generation plant in Sweden, with four blocks and a maximum co-generation output of 520 MW electricity and 950 MW heat. The analysis is carried out on boiler B4. -Biomass Fuel Cycle: centred around Haendeloeverket, Norrkoeping. This plant predominately burns forestry residues, but a variety of fuels are combusted. Haendeloeverket has an installed capacity of 100 MW electricity and 375 MW heat, in a total of three boilers and two back-pressure turbines. The analysis is carried out on boiler P13. -Hydro Fuel Cycle: Klippens Kraftstation, Storuman. Built in 1990-1994, it is the youngest hydro power station in Sweden. It has been designed and built with significant efforts to account for and protect environmental values. Installed capacity is 28 MW. The environmental impact assessment from the construction of this plant is carried out, but the evaluation is still not finalized. The preliminary aggregation aimed to test whether ExternE results could be used to make estimates for the entire Swedish electricity production system. Hence, national results as well as results from other partner countries in ExternE has been applied

  11. Urban Sprawl and Transportation Externalities

    OpenAIRE

    Holcombe, Randall G.; Williams, DeEdgra W.

    2010-01-01

    One argument in support of minimizing urban sprawl is that sprawl creates transportation externalities. A problem with empirically examining the relationship between sprawl and transportation externalities is that sprawl is a difficult concept to quantify. This paper uses a measure of sprawl designed by Ewing, Pendall, and Chen (2002) to examine the relationship between sprawl and commute times, automobile ownership, miles driven, fatal auto accidents, air pollution, and highway expenditures....

  12. Internal hiring or external recruitment?

    OpenAIRE

    DeVaro, Jed

    2016-01-01

    Hiring is one of a firm’s most important decisions. When an employer fills a vacancy with one of its own workers (through promotion or lateral transfer), it forgoes the opportunity to fill the position with a new hire from outside the firm. Although both internal and external hiring methods are used, firms frequently have a bias favoring insiders. Internal and external hires differ in observable characteristics (such as skill levels), as do the employers making each type of hiring decision. U...

  13. Optical memory

    Science.gov (United States)

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  14. A memory module for experimental data handling

    Science.gov (United States)

    De Blois, J.

    1985-02-01

    A compact CAMAC memory module for experimental data handling was developed to eliminate the need of direct memory access in computer controlled measurements. When using autonomous controllers it also makes measurements more independent of the program and enlarges the available space for programs in the memory of the micro-computer. The memory module has three modes of operation: an increment-, a list- and a fifo mode. This is achieved by connecting the main parts, being: the memory (MEM), the fifo buffer (FIFO), the address buffer (BUF), two counters (AUX and ADDR) and a readout register (ROR), by an internal 24-bit databus. The time needed for databus operations is 1 μs, for measuring cycles as well as for CAMAC cycles. The FIFO provides temporary data storage during CAMAC cycles and separates the memory part from the application part. The memory is variable from 1 to 64K (24 bits) by using different types of memory chips. The application part, which forms 1/3 of the module, will be specially designed for each application and is added to the memory chian internal connector. The memory unit will be used in Mössbauer experiments and in thermal neutron scattering experiments.

  15. A memory module for experimental data handling

    International Nuclear Information System (INIS)

    Blois, J. de

    1985-01-01

    A compact CAMAC memory module for experimental data handling was developed to eliminate the need of direct memory access in computer controlled measurements. When using autonomous controllers it also makes measurements more independent of the program and enlarges the available space for programs in the memory of the micro-computer. The memory module has three modes of operation: an increment-, a list- and a fifo mode. This is achieved by connecting the main parts, being: the memory (MEM), the fifo buffer (FIFO), the address buffer (BUF), two counters (AUX and ADDR) and a readout register (ROR), by an internal 24-bit databus. The time needed for databus operations is 1 μs, for measuring cycles as well as for CAMAC cycles. The FIFO provides temporary data storage during CAMAC cycles and separates the memory part from the application part. The memory is variable from 1 to 64K (24 bits) by using different types of memory chips. The application part, which forms 1/3 of the module, will be specially designed for each application and is added to the memory by an internal connector. The memory unit will be used in Moessbauer experiments and in thermal neutron scattering experiments. (orig.)

  16. Spatial memory and animal movement.

    Science.gov (United States)

    Fagan, William F; Lewis, Mark A; Auger-Méthé, Marie; Avgar, Tal; Benhamou, Simon; Breed, Greg; LaDage, Lara; Schlägel, Ulrike E; Tang, Wen-wu; Papastamatiou, Yannis P; Forester, James; Mueller, Thomas

    2013-10-01

    Memory is critical to understanding animal movement but has proven challenging to study. Advances in animal tracking technology, theoretical movement models and cognitive sciences have facilitated research in each of these fields, but also created a need for synthetic examination of the linkages between memory and animal movement. Here, we draw together research from several disciplines to understand the relationship between animal memory and movement processes. First, we frame the problem in terms of the characteristics, costs and benefits of memory as outlined in psychology and neuroscience. Next, we provide an overview of the theories and conceptual frameworks that have emerged from behavioural ecology and animal cognition. Third, we turn to movement ecology and summarise recent, rapid developments in the types and quantities of available movement data, and in the statistical measures applicable to such data. Fourth, we discuss the advantages and interrelationships of diverse modelling approaches that have been used to explore the memory-movement interface. Finally, we outline key research challenges for the memory and movement communities, focusing on data needs and mathematical and computational challenges. We conclude with a roadmap for future work in this area, outlining axes along which focused research should yield rapid progress. © 2013 John Wiley & Sons Ltd/CNRS.

  17. Serotonin, neural markers and memory

    Directory of Open Access Journals (Sweden)

    Alfredo eMeneses

    2015-07-01

    Full Text Available Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The interactions among behavioral tasks, control groups and molecular changes and/or pharmacological effects are mentioned. Neurotransmitter receptors and signaling pathways, during normal and abnormally functioning memory with an emphasis on the behavioral aspects of memory are revised. With focus on serotonin, since as it is a well characterized neurotransmitter, with multiple pharmacological tools, and well characterized downstream signaling in mammals’ species. 5-HT1A, 5-HT4, 5-HT5, 5-HT6 and 5-HT7 receptors as well as SERT (serotonin transporter seem to be useful neural markers and/or therapeutic targets. Certainly, if the mentioned evidence is replicated, then the translatability from preclinical and clinical studies to neural changes might be confirmed. Hypothesis and theories might provide appropriate limits and perspectives of evidence

  18. Ceramic External Pressure Housings For Deep Sea Vehicles

    National Research Council Canada - National Science Library

    Stachiw, J. D; Peters, Donald; McDonald, Glenn

    2006-01-01

    Only glasses, ceramic and carbon fiber reinforced plastic can provide the necessary weight to strength ratio to make the external pressure housings for undersea vehicles positively buoyant at the abyssal design depth...

  19. Disorder-induced microscopic magnetic memory

    International Nuclear Information System (INIS)

    Pierce, M.S.; Buechler, C.R.; Sorensen, L.B.; Turner, J.J.; Kevan, S.D.; Jagla, E.A.; Deutsch, J.M.; Mai, T.; Narayan, O.; Davies, J.E.; Liu, K.; Dunn, J. Hunter; Chesnel, K.M.; Kortright, J.B.; Hellwig, O.; Fullerton, E.E.

    2005-01-01

    Using coherent x-ray speckle metrology, we have measured the influence of disorder on major loop return point memory (RPM) and complementary point memory (CPM) for a series of perpendicular anisotropy Co/Pt multilayer films. In the low disorder limit, the domain structures show no memory with field cycling - no RPM and no CPM. With increasing disorder, we observe the onset and the saturation of both the RPM and the CPM. These results provide the first direct ensemble-sensitive experimental study of the effects of varying disorder on microscopic magnetic memory and are compared against the predictions of existing theories

  20. Priming analogical reasoning with false memories.

    Science.gov (United States)

    Howe, Mark L; Garner, Sarah R; Threadgold, Emma; Ball, Linden J

    2015-08-01

    Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems.

  1. Quantitative measurements of autobiographical memory content.

    Directory of Open Access Journals (Sweden)

    Robert S Gardner

    Full Text Available Autobiographical memory (AM, subjective recollection of past experiences, is fundamental in everyday life. Nevertheless, characterization of the spontaneous occurrence of AM, as well as of the number and types of recollected details, remains limited. The CRAM (Cue-Recalled Autobiographical Memory test (http://cramtest.info adapts and combines the cue-word method with an assessment that collects counts of details recalled from different life periods. The SPAM (Spontaneous Probability of Autobiographical Memories protocol samples introspection during everyday activity, recording memory duration and frequency. These measures provide detailed, naturalistic accounts of AM content and frequency, quantifying essential dimensions of recollection. AM content (∼20 details/recollection decreased with the age of the episode, but less drastically than the probability of reporting remote compared to recent memories. AM retrieval was frequent (∼20/hour, each memory lasting ∼30 seconds. Testable hypotheses of the specific content retrieved in a fixed time from given life periods are presented.

  2. External conference: Geneva University

    CERN Multimedia

    2007-01-01

    ECOLE DE PHYSIQUE Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 - Tél : 022 379 62 73 - Fax: 022 379 69 92 Monday 11 June 2007 COLLOQUE DE LA SECTION DE PHYSIQUE at 17:00 - Stückelberg Auditorium The CERN Axion Solar Telescope (CAST). Motivation, concept, results and potential implications Prof. Konstantin ZIOUTAS / University of Patras/Greece & CERN and CAST-spokesperson Axion is one of the leading dark matter particle candidates. The last few years axion searches are in the spotlight. The physics motivation will be presented. Particles like the axions should be produced also in Stars like our Sun. In magnetic fields axions can coherently oscillate to photons and vice versa (Primakoff effect). CAST searches for solar axions pointing a recycled LHC magnet towards the Sun, and, it provides new results since 2002. Its working principle might well be already at work in outer space, asking for an alternative, though exotic, point of view for certain myst...

  3. External meeting: Geneva University

    CERN Multimedia

    2006-01-01

    Université de Genève Ecole de physique 24 quai Ernest Ansermet 1211 Genève 4 Tél : + 41 22 379 63 83 (secrétariat) Tél : + 41 22 379 62 56 (réception) Fax: + 41 22 379 69 22 Lundi 20 novembre 2006 COLLOQUIUM 17:00 - Auditoire Stückelberg Electrical correlation measurements in quantum nano-structures Dr. Stefan Oberholzer / Basel University Measuring the current-voltage characteristics of small conductors is widely used to characterize their electronic transport properties. In addition to such time-averaged measurements, correlation measurements between temporal fluctuations (noise) around the time-averaged mean current provide us with very important supplementary information about electrical transport. In this talk, I review our experimental work on shot noise, noise which originates from the granularity of charge and the diffraction of the electronic wave-function, and especially address the fundamental relation between electronic scattering experiments and the statistical properties of indist...

  4. Memory, microprocessor, and ASIC

    CERN Document Server

    Chen, Wai-Kai

    2003-01-01

    System Timing. ROM/PROM/EPROM. SRAM. Embedded Memory. Flash Memories. Dynamic Random Access Memory. Low-Power Memory Circuits. Timing and Signal Integrity Analysis. Microprocessor Design Verification. Microprocessor Layout Method. Architecture. ASIC Design. Logic Synthesis for Field Programmable Gate Array (EPGA) Technology. Testability Concepts and DFT. ATPG and BIST. CAD Tools for BIST/DFT and Delay Faults.

  5. Infant Visual Recognition Memory

    Science.gov (United States)

    Rose, Susan A.; Feldman, Judith F.; Jankowski, Jeffery J.

    2004-01-01

    Visual recognition memory is a robust form of memory that is evident from early infancy, shows pronounced developmental change, and is influenced by many of the same factors that affect adult memory; it is surprisingly resistant to decay and interference. Infant visual recognition memory shows (a) modest reliability, (b) good discriminant…

  6. Approaches in estimation of external cost for fuel cycles in the ExternE project

    International Nuclear Information System (INIS)

    Afanas'ev, A.A.; Maksimenko, B.N.

    1998-01-01

    The purposes, content and main results of studies realized within the frameworks of the International Project ExternE which is the first comprehensive attempt to develop general approach to estimation of external cost for different fuel cycles based on utilization of nuclear and fossil fuels, as well as on renewable power sources are discussed. The external cost of a fuel cycle is treated as social and environmental expenditures which are not taken into account by energy producers and consumers, i.e. these are expenditures not included into commercial cost nowadays. The conclusion on applicability of the approach suggested for estimation of population health hazards and environmental impacts connected with electric power generation growth (expressed in money or some other form) is made

  7. Control of crack pattern using memory effect of paste

    International Nuclear Information System (INIS)

    Nakahara, Akio; Shinohara, Yuu; Matsuo, Yousuke

    2011-01-01

    A densely packed colloidal suspension, called as a paste, remembers the direction of external mechanical fields, such as flow and vibration. When the pastes are dried, memories in pastes are visualized as macroscopically anisotropic crack patterns, such as lamellar, radial, ring and spiral. Here, we experimentally investigate how pastes remember such experiences by using paste with different size distribution of colloidal particles. We find that a paste with smaller particles have a better memory, in the sense it remembers external mechanical fields at smaller solid volume fraction, which implies that interparticle forces between colloidal particles play an important role in memory effects, causing a quantitative change in the phase diagram for the same material. This result supports the hypothesis that memories in pastes are maintained as microscopically anisotropic network structure of colloidal particles, connected via interparticle forces between colloidal particles, such as van der Waals interaction.

  8. Collective memory: a perspective from (experimental) clinical psychology.

    Science.gov (United States)

    Wessel, Ineke; Moulds, Michelle L

    2008-04-01

    This paper considers the concept of collective memory from an experimental clinical psychology perspective. Exploration of the term collective reveals a broad distinction between literatures that view collective memories as a property of groups (collectivistic memory) and those that regard these memories as a property of individuals who are, to a greater or lesser extent, an integral part of their social environment (social memory). First, we argue that the understanding of collectivistic memory phenomena may benefit from drawing parallels with current psychological models such as the self-memory system theory of individualistic autobiographical memory. Second, we suggest that the social memory literature may inform the study of trauma-related disorders. We argue that a factual focus induced by collaborative remembering may be beneficial to natural recovery in the immediate aftermath of trauma, and propose that shared remembering techniques may provide a useful addition to the treatment of post-traumatic stress disorder.

  9. Reality of near-death-experience memories: Evidence from a psychodynamic and electrophysiological integrated study

    Directory of Open Access Journals (Sweden)

    Arianna ePalmieri

    2014-06-01

    Full Text Available The nature of near-death experiences (NDEs is largely unknown but recent evidence suggests the intriguing possibility that NDEs may refer to actually perceived, and stored, experiences (although not necessarily in relation to the external physical world. We adopted an integrated approach involving a hypnosis-based clinical protocol to improve recall and decrease memory inaccuracy together with Electroencephalography (EEG recording in order to investigate the characteristics of NDE memories and their neural markers compared to memories of both real and imagined events. We included 10 participants with NDEs, defined by the Greyson NDE scale, and 10 control subjects without NDE. Memories were assessed using the Memory Characteristics Questionnaire.Our hypnosis-based protocol increased the amount of details in the recall of all kind of memories considered (NDE, real, and imagined events. Findings showed that NDE memories were similar to real memories in terms of detail richness, self-referential, and emotional information. Moreover, NDE memories were significantly different from memories of imagined events. The pattern of EEG results indicated that real memories recall was positively associated with two memory-related frequency bands, i.e., high alpha and gamma. NDE memories were linked with theta band, a well-known marker of episodic memory. The recall of NDE memories was also related to delta band, which indexes processes such as the recollection of the past, as well as trance states, hallucinations, and other related portals to transpersonal experience. It is notable that the EEG pattern of correlations for NDE memories recall differed from the pattern for memories of imagined events. In conclusion, our findings suggest that, at a phenomenological level, NDE memories cannot be considered equivalent to imagined memories, and at a neural level, NDE memories are stored as episodic memories of events experienced in a peculiar state of consciousness.

  10. Working Memory Intervention: A Reading Comprehension Approach

    Science.gov (United States)

    Perry, Tracy L.; Malaia, Evguenia

    2013-01-01

    For any complex mental task, people rely on working memory. Working memory capacity (WMC) is one predictor of success in learning. Historically, attempts to improve verbal WM through training have not been effective. This study provided elementary students with WM consolidation efficiency training to answer the question, Can reading comprehension…

  11. Episodic memory and the witness trump card.

    Science.gov (United States)

    Henry, Jeremy; Craver, Carl

    2018-01-01

    We accept Mahr & Csibra's (M&C's) causal claim that episodic memory provides humans with the means for evaluating the veracity of reports about non-occurrent events. We reject their evolutionary argument that this is the proper function of episodic memory. We explore three intriguing implications of the causal claim, for cognitive neuropsychology, comparative psychology, and philosophy.

  12. Providing Continuous Assurance

    NARCIS (Netherlands)

    Kocken, Jonne; Hulstijn, Joris

    2017-01-01

    It has been claimed that continuous assurance can be attained by combining continuous monitoring by management, with continuous auditing of data streams and the effectiveness of internal controls by an external auditor. However, we find that in existing literature the final step to continuous

  13. Ghrelin: A link between memory and ingestive behavior.

    Science.gov (United States)

    Hsu, Ted M; Suarez, Andrea N; Kanoski, Scott E

    2016-08-01

    Feeding is a highly complex behavior that is influenced by learned associations between external and internal cues. The type of excessive feeding behavior contributing to obesity onset and metabolic deficit may be based, in part, on conditioned appetitive and ingestive behaviors that occur in response to environmental and/or interoceptive cues associated with palatable food. Therefore, there is a critical need to understand the neurobiology underlying learned aspects of feeding behavior. The stomach-derived "hunger" hormone, ghrelin, stimulates appetite and food intake and may function as an important biological substrate linking mnemonic processes with feeding control. The current review highlights data supporting a role for ghrelin in mediating the cognitive and neurobiological mechanisms that underlie conditioned feeding behavior. We discuss the role of learning and memory on food intake control (with a particular focus on hippocampal-dependent memory processes) and provide an overview of conditioned cephalic endocrine responses. A neurobiological framework is provided through which conditioned cephalic ghrelin secretion signals in neurons in the hippocampus, which then engage orexigenic neural circuitry in the lateral hypothalamus to express learned feeding behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Visual memory needs categories

    OpenAIRE

    Olsson, Henrik; Poom, Leo

    2005-01-01

    Capacity limitations in the way humans store and process information in working memory have been extensively studied, and several memory systems have been distinguished. In line with previous capacity estimates for verbal memory and memory for spatial information, recent studies suggest that it is possible to retain up to four objects in visual working memory. The objects used have typically been categorically different colors and shapes. Because knowledge about categories is stored in long-t...

  15. Non-volatile memories

    CERN Document Server

    Lacaze, Pierre-Camille

    2014-01-01

    Written for scientists, researchers, and engineers, Non-volatile Memories describes the recent research and implementations in relation to the design of a new generation of non-volatile electronic memories. The objective is to replace existing memories (DRAM, SRAM, EEPROM, Flash, etc.) with a universal memory model likely to reach better performances than the current types of memory: extremely high commutation speeds, high implantation densities and retention time of information of about ten years.

  16. Temporal Organization of Sound Information in Auditory Memory

    OpenAIRE

    Song, Kun; Luo, Huan

    2017-01-01

    Memory is a constructive and organizational process. Instead of being stored with all the fine details, external information is reorganized and structured at certain spatiotemporal scales. It is well acknowledged that time plays a central role in audition by segmenting sound inputs into temporal chunks of appropriate length. However, it remains largely unknown whether critical temporal structures exist to mediate sound representation in auditory memory. To address the issue, here we designed ...

  17. Shape memory of human red blood cells.

    Science.gov (United States)

    Fischer, Thomas M

    2004-05-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spheres. Shape excursions were induced by shear flow. In virtually all red cells, a shape memory was found. After stop of flow and during the return of the latex spheres to the original location, the red cell shape was biconcave. The return occurred by a tank-tread motion of the membrane. The memory could not be eliminated by deforming the red cells in shear flow up to 4 h at room temperature as well as at 37 degrees C. It is suggested that 1). the characteristic time of stress relaxation is >80 min and 2). red cells in vivo also have a shape memory.

  18. Experimental Effects of Acute Exercise on Prospective Memory and False Memory.

    Science.gov (United States)

    Green, David; Loprinzi, Paul D

    2018-01-01

    Research demonstrates that acute exercise can enhance retrospective episodic memory performance. However, limited research has examined the effects of acute exercise on prospective memory, and no studies have examined the effects of exercise on false memory performance. This study examined the potential effects of acute exercise on prospective memory and false memory performance. A between-group randomized controlled trial was employed, with participants (college students; M age  = 20 years) randomized into an exercise group (15-minute acute bout of treadmill walking; N = 25) or a control group (15 minutes of sitting; N = 26). Prospective memory was assessed from two laboratory and two naturalistic assessments outside the lab. False memory was assessed using a word-list trial. There were no statistically significant differences in prospective memory based on group allocation (F Group×Time  = 1.17; P = 0.32; η 2  = 0.06). However, the control group recalled more false words and had a higher rate of false memory recognition (F Group×Time  = 3.15; P = 0.01; η 2  = 0.26). These findings indicate that acute moderate-intensity aerobic exercise is not associated with prospective memory performance but provides some suggestive evidence that acute exercise may reduce the rate of false memories.

  19. Accessing forgotten memory traces from long-term memory via visual movements

    Directory of Open Access Journals (Sweden)

    Estela eCamara

    2014-11-01

    Full Text Available Because memory retrieval often requires overt responses, it is difficult to determine to what extend forgetting occurs as a problem in explicit accessing of long-term memory traces. In this study, we used eye-tracking measures in combination with a behavioural task that favoured high forgetting rates to investigate the existence of memory traces from long-term memory in spite of failure in accessing them consciously. In 2 experiments, participants were encouraged to encode a large set of sound-picture-location associations. In a later test, sounds were presented and participants were instructed to visually scan, before a verbal memory report, for the correct location of the associated pictures in an empty screen. We found the reactivation of associated memories by sound cues at test biased oculomotor behaviour towards locations congruent with memory representations, even when participants failed to consciously provide a memory report of it. These findings reveal the emergence of a memory-guided behaviour that can be used to map internal representations of forgotten memories from long-term memory.

  20. Autobiographical memory and hyperassociativity in the dreaming brain: Implications for memory consolidation in sleep

    Directory of Open Access Journals (Sweden)

    Caroline L Horton

    2015-07-01

    Full Text Available In this paper we argue that autobiographical memory activity across sleep and wake can provide insight into the nature of dreaming, and vice versa. Activated memories within the sleeping brain reflect one’s personal life history (autobiography. They can appear in largely fragmentary forms and differ from conventional manifestations of episodic memory. Autobiographical memories in dreams can be sampled from non-REM as well as REM periods, which contain fewer episodic references and become more bizarre across the night. Salient fragmented memory features are activated in sleep and re-bound with fragments not necessarily emerging from the same memory, thus de-contextualising those memories and manifesting as experiences that differ from waking conceptions. The constructive nature of autobiographical recall further encourages synthesis of these hyper-associated images into an episode via recalling and reporting dreams. We use a model of autobiographical memory to account for the activation of memories in dreams as a reflection of sleep-dependent memory consolidation processes. We focus in particular on the hyperassociative nature of autobiographical memory during sleep.

  1. Enlargement of the External Mobility Programme

    CERN Multimedia

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts, having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has raised considerable interest from both CERN personnel as well as from several major European companies. CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CERN fo...

  2. Enlargement of the External Mobility Programme

    CERN Multimedia

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has attracted considerable interest from both CERN personnel as well as from several major European companies. The CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CE...

  3. Radionuclide evaluation in malignant external otitis

    International Nuclear Information System (INIS)

    Wolosker, Sara; Penha Costa Marques, Marise da; Fonseca, Lea Miriam Barbosa da; Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ

    1996-01-01

    Malignant external otitis (MEO) is a severe infection of the external auditory canal that can result in osteomyelitis of the skull base. Twenty-eight patients with MEO (19 diabetics, 8 with AIDS and 1 with acute mielogenous leukemia) were evaluated using 99m Tc-MDP bone scintigraphy. 67 Ga citrate and computed tomography (CT) at the time of diagnosis for establishing the MEO extent. 67 Ga scans were obtained periodically in order to assess the evolution of the treatment. 99m Tc scans had shown high sensitivity and specificity in assessing the bone disease. Serial 67 Ga scans had shown to be valuable indicators of infection remission. CT scans provided poor diagnosis of early bone involvement. (author). 26 refs., 4 figs

  4. Dissemination of CERN Technologies Through External Entrepreneurs

    CERN Document Server

    Lande, Bjørnulf Visdal; Huuse, Henning

    2008-01-01

    This study focuses on dissemination of innovations through external entrepreneurs. The innovations studied are developed at the European Organization for Nuclear Research (CERN) and commercialized by entrepreneurs establishing spin-off companies on the outside of the Organization. The objective of this study is to provide knowledge to facilitate future external entrepreneurs to increase dissemination of CERN technologies. The research questions looks at the timeline from preparations for creating the spin-off company, until having a product for commercialization in the market. A qualitative cross case investigation was conducted to assess the experiences of four spin-off companies. A framework was created to structure the discussion by finding and categorizing impeding- and success factors seen from the entrepreneurs point of view. The findings where structured in three phases respectively, the time before starting the company, the beginning of the company and the final development before selling products. Th...

  5. The Effect of External Representations on Compare Word Problems: Supporting Mental Model Construction

    Science.gov (United States)

    Munez, David; Orrantia, Josetxu; Rosales, Javier

    2013-01-01

    This study explored the effectiveness of external representations presented together with compare word problems, and whether such effectiveness was moderated by working memory. Participants were 49 secondary school students. Each participant solved 48 problems presented in 4 presentation types that included 2 difficulty treatments (number of steps…

  6. Resistively heated shape memory polymer device

    Energy Technology Data Exchange (ETDEWEB)

    Marion, III, John E.; Bearinger, Jane P.; Wilson, Thomas S.; Maitland, Duncan J.

    2017-09-05

    A resistively heated shape memory polymer device is made by providing a rod, sheet or substrate that includes a resistive medium. The rod, sheet or substrate is coated with a first shape memory polymer providing a coated intermediate unit. The coated intermediate unit is in turn coated with a conductive material providing a second intermediate unit. The second coated intermediate unit is in turn coated with an outer shape memory polymer. The rod, sheet or substrate is exposed and an electrical lead is attached to the rod, sheet or substrate. The conductive material is exposed and an electrical lead is attached to the conductive material.

  7. Resistively heated shape memory polymer device

    Energy Technology Data Exchange (ETDEWEB)

    Marion, III, John E.; Bearinger, Jane P.; Wilson, Thomas S.; Maitland, Duncan J.

    2016-10-25

    A resistively heated shape memory polymer device is made by providing a rod, sheet or substrate that includes a resistive medium. The rod, sheet or substrate is coated with a first shape memory polymer providing a coated intermediate unit. The coated intermediate unit is in turn coated with a conductive material providing a second intermediate unit. The second coated intermediate unit is in turn coated with an outer shape memory polymer. The rod, sheet or substrate is exposed and an electrical lead is attached to the rod, sheet or substrate. The conductive material is exposed and an electrical lead is attached to the conductive material.

  8. Recent life stress exposure is associated with poorer long-term memory, working memory, and self-reported memory.

    Science.gov (United States)

    Shields, Grant S; Doty, Dominique; Shields, Rebecca H; Gower, Garrett; Slavich, George M; Yonelinas, Andrew P

    2017-11-01

    Although substantial research has examined the effects of stress on cognition, much of this research has focused on acute stress (e.g. manipulated in the laboratory) or chronic stress (e.g. persistent interpersonal or financial difficulties). In contrast, the effects of recent life stress on cognition have been relatively understudied. To address this issue, we examined how recent life stress is associated with long-term, working memory, and self-reported memory in a sample of 142 healthy young adults who were assessed at two time points over a two-week period. Recent life stress was measured using the newly-developed Stress and Adversity Inventory for Daily Stress (Daily STRAIN), which assesses the frequency of relatively common stressful life events and difficulties over the preceding two weeks. To assess memory performance, participants completed both long-term and working memory tasks. Participants also provided self-reports of memory problems. As hypothesized, greater recent life stress exposure was associated with worse performance on measures of long-term and working memory, as well as more self-reported memory problems. These associations were largely robust while controlling for possible confounds, including participants' age, sex, and negative affect. The findings indicate that recent life stress exposure is broadly associated with worse memory. Future studies should thus consider assessing recent life stress as a potential predictor, moderator, or covariate of memory performance.

  9. Salam Memorial

    CERN Document Server

    Rubbia, Carlo

    1997-01-01

    by T.W.B. KIBBLE / Blackett Laboratory, Imperial College, London. Recollections of Abdus Salam at Imperial College I shall give a personal account of Professor Salam's life and work from the perspective of a colleague at Imperial College, concentrating particularly but not exclusively on the period leading up to the discovery of the electro-weak theory. If necessary I could perhaps give more detail, but only once I have given more thought to what ground I shall cover. by Sheldon Lee GLASHOW / Harvard University, Cambridge, MA, USA. Memories of Abdus Salam. My interactions with Abdus Salam, weak as they have been, extended over five decades. I regret that we never once collaborated in print or by correspondence. I visited Abdus only twice in London and twice again in Trieste, and met him at the occasional conference or summer school. Our face-to-face encounters could be counted on one's fingers and toes, but we became the best of friends. Others will discuss Abdus as an inspiring teacher, as a great scientist,...

  10. Mood-Congruent Memory and Natural Mood: New Evidence.

    Science.gov (United States)

    Mayer, John D.; And Others

    1995-01-01

    Presents new evidence that everyday mood does bring about a hypothesized effect on memory, termed mood-congruent memory (MCM). Results of three studies provided evidence for MCM among normal individuals (n=614). Findings support prior studies and bolster notions that mood and memory constantly covary in everyday experience. (RJM)

  11. Working Memory and Learning: A Practical Guide for Teachers

    Science.gov (United States)

    Gathercole, Susan E.; Alloway, Tracy Packiam

    2008-01-01

    A good working memory is crucial to becoming a successful leaner, yet there is very little material available in an easy-to-use format that explains the concept and offers practitioners ways to support children with poor working memory in the classroom. This book provides a coherent overview of the role played by working memory in learning during…

  12. The Benefits of Targeted Memory Reactivation for Consolidation in Sleep are Contingent on Memory Accuracy and Direct Cue-Memory Associations.

    Science.gov (United States)

    Cairney, Scott A; Lindsay, Shane; Sobczak, Justyna M; Paller, Ken A; Gaskell, M Gareth

    2016-05-01

    To investigate how the effects of targeted memory reactivation (TMR) are influenced by memory accuracy prior to sleep and the presence or absence of direct cue-memory associations. 30 participants associated each of 50 pictures with an unrelated word and then with a screen location in two separate tasks. During picture-location training, each picture was also presented with a semantically related sound. The sounds were therefore directly associated with the picture locations but indirectly associated with the words. During a subsequent nap, half of the sounds were replayed in slow wave sleep (SWS). The effect of TMR on memory for the picture locations (direct cue-memory associations) and picture-word pairs (indirect cue-memory associations) was then examined. TMR reduced overall memory decay for recall of picture locations. Further analyses revealed a benefit of TMR for picture locations recalled with a low degree of accuracy prior to sleep, but not those recalled with a high degree of accuracy. The benefit of TMR for low accuracy memories was predicted by time spent in SWS. There was no benefit of TMR for memory of the picture-word pairs, irrespective of memory accuracy prior to sleep. TMR provides the greatest benefit to memories recalled with a low degree of accuracy prior to sleep. The memory benefits of TMR may also be contingent on direct cue-memory associations. © 2016 Associated Professional Sleep Societies, LLC.

  13. Structural brain correlates of associative memory in older adults.

    Science.gov (United States)

    Becker, Nina; Laukka, Erika J; Kalpouzos, Grégoria; Naveh-Benjamin, Moshe; Bäckman, Lars; Brehmer, Yvonne

    2015-09-01

    Associative memory involves binding two or more items into a coherent memory episode. Relative to memory for single items, associative memory declines greatly in aging. However, older individuals vary substantially in their ability to memorize associative information. Although functional studies link associative memory to the medial temporal lobe (MTL) and prefrontal cortex (PFC), little is known about how volumetric differences in MTL and PFC might contribute to individual differences in associative memory. We investigated regional gray-matter volumes related to individual differences in associative memory in a sample of healthy older adults (n=54; age=60years). To differentiate item from associative memory, participants intentionally learned face-scene picture pairs before performing a recognition task that included single faces, scenes, and face-scene pairs. Gray-matter volumes were analyzed using voxel-based morphometry region-of-interest (ROI) analyses. To examine volumetric differences specifically for associative memory, item memory was controlled for in the analyses. Behavioral results revealed large variability in associative memory that mainly originated from differences in false-alarm rates. Moreover, associative memory was independent of individuals' ability to remember single items. Older adults with better associative memory showed larger gray-matter volumes primarily in regions of the left and right lateral PFC. These findings provide evidence for the importance of PFC in intentional learning of associations, likely because of its involvement in organizational and strategic processes that distinguish older adults with good from those with poor associative memory. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. What works in auditory working memory? A neural oscillations perspective.

    Science.gov (United States)

    Wilsch, Anna; Obleser, Jonas

    2016-06-01

    Working memory is a limited resource: brains can only maintain small amounts of sensory input (memory load) over a brief period of time (memory decay). The dynamics of slow neural oscillations as recorded using magneto- and electroencephalography (M/EEG) provide a window into the neural mechanics of these limitations. Especially oscillations in the alpha range (8-13Hz) are a sensitive marker for memory load. Moreover, according to current models, the resultant working memory load is determined by the relative noise in the neural representation of maintained information. The auditory domain allows memory researchers to apply and test the concept of noise quite literally: Employing degraded stimulus acoustics increases memory load and, at the same time, allows assessing the cognitive resources required to process speech in noise in an ecologically valid and clinically relevant way. The present review first summarizes recent findings on neural oscillations, especially alpha power, and how they reflect memory load and memory decay in auditory working memory. The focus is specifically on memory load resulting from acoustic degradation. These findings are then contrasted with contextual factors that benefit neural as well as behavioral markers of memory performance, by reducing representational noise. We end on discussing the functional role of alpha power in auditory working memory and suggest extensions of the current methodological toolkit. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

  15. Use of explicit memory cues following parietal lobe lesions.

    Science.gov (United States)

    Dobbins, Ian G; Jaeger, Antonio; Studer, Bettina; Simons, Jon S

    2012-11-01

    The putative role of the lateral parietal lobe in episodic memory has recently become a topic of considerable debate, owing primarily to its consistent activation for studied materials during functional magnetic resonance imaging studies of recognition. Here we examined the performance of patients with parietal lobe lesions using an explicit memory cueing task in which probabilistic cues ("Likely Old" or "Likely New"; 75% validity) preceded the majority of verbal recognition memory probes. Without cues, patients and control participants did not differ in accuracy. However, group differences emerged during the "Likely New" cue condition with controls responding more accurately than parietal patients when these cues were valid (preceding new materials) and trending towards less accuracy when these cues were invalid (preceding old materials). Both effects suggest insufficient integration of external cues into memory judgments on the part of the parietal patients whose cued performance largely resembled performance in the complete absence of cues. Comparison of the parietal patients to a patient group with frontal lobe lesions suggested the pattern was specific to parietal and adjacent area lesions. Overall, the data indicate that parietal lobe patients fail to appropriately incorporate external cues of novelty into recognition attributions. This finding supports a role for the lateral parietal lobe in the adaptive biasing of memory judgments through the integration of external cues and internal memory evidence. We outline the importance of such adaptive biasing through consideration of basic signal detection predictions regarding maximum possible accuracy with and without informative environmental cues. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Lessons learned from external hazards

    Energy Technology Data Exchange (ETDEWEB)

    Peinador, Miguel; Zerger, Benoit [European Commisison Joint Research Centre, Petten (Netherlands). Inst. for Energy and Transport; Ramos, Manuel Martin [European Commission Joint Research Centre, Brussels (Belgium). Nuclear Safety and Security Coordination; Wattrelos, Didier [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Maqua, Michael [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Koeln (Germany)

    2014-01-15

    This paper presents a study performed by the European Clearinghouse of the Joint Research Centre on Operational Experience for nuclear power plants in cooperation with IRSN and GRS covering events reported by nuclear power plants in relation to external hazards. It summarizes the review of 235 event reports from 3 different databases. The events were grouped in 9 categories according to the nature of the external hazard involved, and the specific lessons learned and recommendations that can be derived from each of these categories are presented. Additional 'cross-cutting' recommendations covering several or all the external hazards considered are also discussed. These recommendations can be useful in preventing this type of events from happening again or in limiting their consequences. The study was launched in 2010 and therefore it does not cover the Fukushima event. This paper presents the main findings and recommendations raised by this study. (orig.)

  17. A Role for the Left Angular Gyrus in Episodic Simulation and Memory.

    Science.gov (United States)

    Thakral, Preston P; Madore, Kevin P; Schacter, Daniel L

    2017-08-23

    Functional magnetic resonance imaging (fMRI) studies indicate that episodic simulation (i.e., imagining specific future experiences) and episodic memory (i.e., remembering specific past experiences) are associated with enhanced activity in a common set of neural regions referred to as the core network. This network comprises the hippocampus, medial prefrontal cortex, and left angular gyrus, among other regions. Because fMRI data are correlational, it is unknown whether activity increases in core network regions are critical for episodic simulation and episodic memory. In the current study, we used MRI-guided transcranial magnetic stimulation (TMS) to assess whether temporary disruption of the left angular gyrus would impair both episodic simulation and memory (16 participants, 10 females). Relative to TMS to a control site (vertex), disruption of the left angular gyrus significantly reduced the number of internal (i.e., episodic) details produced during the simulation and memory tasks, with a concomitant increase in external detail production (i.e., semantic, repetitive, or off-topic information), reflected by a significant detail by TMS site interaction. Difficulty in the simulation and memory tasks also increased after TMS to the left angular gyrus relative to the vertex. In contrast, performance in a nonepisodic control task did not differ statistically as a function of TMS site (i.e., number of free associates produced or difficulty in performing the free associate task). Together, these results are the first to demonstrate that the left angular gyrus is critical for both episodic simulation and episodic memory. SIGNIFICANCE STATEMENT Humans have the ability to imagine future episodes (i.e., episodic simulation) and remember episodes from the past (i.e., episodic memory). A wealth of neuroimaging studies have revealed that these abilities are associated with enhanced activity in a core network of neural regions, including the hippocampus, medial prefrontal

  18. External dosimetry sources and shielding

    International Nuclear Information System (INIS)

    Calisto, Washington

    1994-01-01

    A definition of external dosimetry r external sources dosimetry,physical and mathematical treatment of the interaction of gamma radiation with a minimal area in that direction. Concept of attenuation coefficient, cumulated effect by polyenergetic sources, exposition rate, units, cumulated dose,shielding, foton shielding, depth calculation, materials used for shielding.Beta shielding, consideration of range and maximum β energy , low stopping radiation by use of low Z shielding. Tables for β energy of β emitters, I (tau) factor, energy-range curves for β emitters in aqueous media, gamma attenuation factors for U, W and Pb. Y factor for bone tissue,muscle and air, build-up factors

  19. Media multitasking and memory: Differences in working memory and long-term memory.

    Science.gov (United States)

    Uncapher, Melina R; K Thieu, Monica; Wagner, Anthony D

    2016-04-01

    Increasing access to media in the 21st century has led to a rapid rise in the prevalence of media multitasking (simultaneous use of multiple media streams). Such behavior is associated with various cognitive differences, such as difficulty filtering distracting information and increased trait impulsivity. Given the rise in media multitasking by children, adolescents, and adults, a full understanding of the cognitive profile of media multitaskers is imperative. Here we investigated the relationship between chronic media multitasking and working memory (WM) and long-term memory (LTM) performance. Four key findings are reported (1) heavy media multitaskers (HMMs) exhibited lower WM performance, regardless of whether external distraction was present or absent; (2) lower performance on multiple WM tasks predicted lower LTM performance; (3) media multitasking-related differences in memory reflected differences in discriminability rather than decision bias; and (4) attentional impulsivity correlated with media multitasking behavior and reduced WM performance. These findings suggest that chronic media multitasking is associated with a wider attentional scope/higher attentional impulsivity, which may allow goal-irrelevant information to compete with goal-relevant information. As a consequence, heavy media multitaskers are able to hold fewer or less precise goal-relevant representations in WM. HMMs' wider attentional scope, combined with their diminished WM performance, propagates forward to yield lower LTM performance. As such, chronic media multitasking is associated with a reduced ability to draw on the past--be it very recent or more remote--to inform present behavior.

  20. Organizational memory: from expectations memory to procedural memory

    NARCIS (Netherlands)

    Ebbers, J.J.; Wijnberg, N.M.

    2009-01-01

    Organizational memory is not just the stock of knowledge about how to do things, but also of expectations of organizational members vis-à-vis each other and the organization as a whole. The central argument of this paper is that this second type of organizational memory -organizational expectations

  1. Auditory and visual memory in musicians and nonmusicians

    OpenAIRE

    Cohen, Michael A.; Evans, Karla K.; Horowitz, Todd S.; Wolfe, Jeremy M.

    2011-01-01

    Numerous studies have shown that musicians outperform nonmusicians on a variety of tasks. Here we provide the first evidence that musicians have superior auditory recognition memory for both musical and nonmusical stimuli, compared to nonmusicians. However, this advantage did not generalize to the visual domain. Previously, we showed that auditory recognition memory is inferior to visual recognition memory. Would this be true even for trained musicians? We compared auditory and visual memory ...

  2. Self-Testing Static Random-Access Memory

    Science.gov (United States)

    Chau, Savio; Rennels, David

    1991-01-01

    Proposed static random-access memory for computer features improved error-detecting and -correcting capabilities. New self-testing scheme provides for detection and correction of errors at any time during normal operation - even while data being written into memory. Faults in equipment causing errors in output data detected by repeatedly testing every memory cell to determine whether it can still store both "one" and "zero", without destroying data stored in memory.

  3. Confabulation and memory impairments following frontal lobe lesions

    OpenAIRE

    Turner, Martha

    2005-01-01

    Neuroimaging studies have provided considerable evidence for frontal lobe involvement in memory processing. Memory impairments arc also frequently reported in patients with frontal lobe lesions. However detailed anatomical localisation is rare, making integration of lesion and imaging findings difficult. An investigation of the functional and anatomical contributions of the frontal lobes to memory was conducted in 42 patients with frontal lobe lesions, examining memory processes identified in...

  4. Stochastic memory: getting memory out of noise

    Science.gov (United States)

    Stotland, Alexander; di Ventra, Massimiliano

    2011-03-01

    Memory circuit elements, namely memristors, memcapacitors and meminductors, can store information without the need of a power source. These systems are generally defined in terms of deterministic equations of motion for the state variables that are responsible for memory. However, in real systems noise sources can never be eliminated completely. One would then expect noise to be detrimental for memory. Here, we show that under specific conditions on the noise intensity memory can actually be enhanced. We illustrate this phenomenon using a physical model of a memristor in which the addition of white noise into the state variable equation improves the memory and helps the operation of the system. We discuss under which conditions this effect can be realized experimentally, discuss its implications on existing memory systems discussed in the literature, and also analyze the effects of colored noise. Work supported in part by NSF.

  5. Andra long term memory project - 59277

    International Nuclear Information System (INIS)

    Charton, Patrick; Boissier, Fabrice; Martin, Guillaume

    2012-01-01

    Document available in abstract form only. Full text of publication follows: Long term memory of repositories is required by safety, reversibility and social expectations. Thus Andra has implemented since 2010 a long-term memory project to reinforce and diversify its current arrangements in this field, as well as to explore opportunities to extend memory keeping over thousands years. The project includes opportunity studies of dedicated facilities. The 'Ecotheque' and 'Geotheque' projects contribute to memory respectively through environmental and geological samples preservation. The options of creating (i) an archive centre for Andra's interim and permanent archives, (ii) an artist center to study the contribution of arts to memory preservation, (iii) a museum of radioactive waste disposal history and technology (radium industry..., sea disposal, current solutions...) are considered. Other studies provided by the project examine our heritage. This includes the continuity of languages and symbolic systems, the continuity of writing and engraving methods, the archaeology of landscapes (memory of the earths evolution, multi-century memory of industrial and agricultural landscapes), the archaeology practices (how might a future archaeologist be interested in our current activity?), the preservation of historical sites and industrial memory, the continuity of institutional organizations, the memory and history of science evolution as well as broad history

  6. Mental Imagery and Visual Working Memory

    Science.gov (United States)

    Keogh, Rebecca; Pearson, Joel

    2011-01-01

    Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage. PMID:22195024

  7. Mental imagery and visual working memory.

    Directory of Open Access Journals (Sweden)

    Rebecca Keogh

    Full Text Available Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.

  8. Mental imagery and visual working memory.

    Science.gov (United States)

    Keogh, Rebecca; Pearson, Joel

    2011-01-01

    Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.

  9. Modeling the Role of Working Memory and Episodic Memory in Behavioral Tasks

    OpenAIRE

    Zilli, Eric A.; Hasselmo, Michael E.

    2008-01-01

    The mechanisms of goal-directed behavior have been studied using reinforcement learning theory, but these theoretical techniques have not often been used to address the role of memory systems in performing behavioral tasks. The present work addresses this shortcoming by providing a way in which working memory and episodic memory may be included in the reinforcement learning framework, then simulating the successful acquisition and performance of six behavioral tasks, drawn from or inspired by...

  10. Resistive content addressable memory based in-memory computation architecture

    KAUST Repository

    Salama, Khaled N.; Zidan, Mohammed A.; Kurdahi, Fadi; Eltawil, Ahmed M.

    2016-01-01

    Various examples are provided examples related to resistive content addressable memory (RCAM) based in-memory computation architectures. In one example, a system includes a content addressable memory (CAM) including an array of cells having a memristor based crossbar and an interconnection switch matrix having a gateless memristor array, which is coupled to an output of the CAM. In another example, a method, includes comparing activated bit values stored a key register with corresponding bit values in a row of a CAM, setting a tag bit value to indicate that the activated bit values match the corresponding bit values, and writing masked key bit values to corresponding bit locations in the row of the CAM based on the tag bit value.

  11. Auditory recognition memory is inferior to visual recognition memory.

    Science.gov (United States)

    Cohen, Michael A; Horowitz, Todd S; Wolfe, Jeremy M

    2009-04-07

    Visual memory for scenes is surprisingly robust. We wished to examine whether an analogous ability exists in the auditory domain. Participants listened to a variety of sound clips and were tested on their ability to distinguish old from new clips. Stimuli ranged from complex auditory scenes (e.g., talking in a pool hall) to isolated auditory objects (e.g., a dog barking) to music. In some conditions, additional information was provided to help participants with encoding. In every situation, however, auditory memory proved to be systematically inferior to visual memory. This suggests that there exists either a fundamental difference between auditory and visual stimuli, or, more plausibly, an asymmetry between auditory and visual processing.

  12. Resistive content addressable memory based in-memory computation architecture

    KAUST Repository

    Salama, Khaled N.

    2016-12-08

    Various examples are provided examples related to resistive content addressable memory (RCAM) based in-memory computation architectures. In one example, a system includes a content addressable memory (CAM) including an array of cells having a memristor based crossbar and an interconnection switch matrix having a gateless memristor array, which is coupled to an output of the CAM. In another example, a method, includes comparing activated bit values stored a key register with corresponding bit values in a row of a CAM, setting a tag bit value to indicate that the activated bit values match the corresponding bit values, and writing masked key bit values to corresponding bit locations in the row of the CAM based on the tag bit value.

  13. Detailed Sensory Memory, Sloppy Working Memory

    OpenAIRE

    Sligte, Ilja G.; Vandenbroucke, Annelinde R. E.; Scholte, H. Steven; Lamme, Victor A. F.

    2010-01-01

    Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity limits and progressively longer lifetimes. Still, the resolution (or amount of visual detail) of each VSTM stage has remained unexplored and we test this in the present study. We presented people with a...

  14. Autobiographical Memory: a clinical perspective

    Directory of Open Access Journals (Sweden)

    Nadja eUrbanowitsch

    2013-12-01

    Full Text Available Autobiographical memory (ABM comprises memories of one’s own past that are characterized by a sense of subjective time and autonoetic awareness. Although ABM deficits are among the primary symptoms of patients with major psychiatric conditions such as mild cognitive impairment (MCI and Alzheimer Disease (AD or chronic schizophrenia large clinical studies are scarce. We therefore summarize and discuss the results of our clinical studies on ABM deficits in the respective conditions. In these studies ABM was assessed by using the same instrument – i.e. the Erweitertes Autobiographisches Gedächtnis Inventar (E-AGI – thus allowing a direct comparison between diagnostic groups. Episodic ABM, especially the richness of details was impaired already in MCI and in beginning AD. Semantic memories were spared until moderate stages, indicating a dissociation between both memory systems. A recency effect was detectable in cognitively unimpaired subjects and vanished in patients with AD. A similar pattern of deficits was found in patients with chronic schizophrenia but not in patients with major depression. These autobiographical memory deficits were not accounted for by gender, or education level and did not apply for the physiological ageing process in otherwise healthy elderly. In conclusion, ABM deficits are frequently found in AD and chronic schizophrenia and primarily involve episodic rather than semantic memories. This dissociation corresponds to the multiple trace theory which hypothesized that these memory functions refer to distinct neuronal systems. The semi-structured interview E-AGI used to discern ABM changes provided a sufficient reliability measures, moreover potential effects of a number of important confounders could be falsified so far. These findings underline the relevance of ABM-assessments in clinical practice.

  15. On recency and echoic memory.

    Science.gov (United States)

    Gardiner, J M

    1983-08-11

    In short-term memory, the tendency for the last few (recency) items from a verbal sequence to be increasingly well recalled is more pronounced if the items are spoken rather than written. This auditory recency advantage has been quite generally attributed to echoic memory, on the grounds that in the auditory, but not the visual, mode, sensory memory persists just long enough to supplement recall of the most recent items. This view no longer seems tenable. There are now several studies showing that an auditory recency advantage occurs not only in long-term memory, but under conditions in which it cannot possibly be attributed to echoic memory. Also, similar recency phenomena have been discovered in short-term memory when the items are lip-read, or presented in sign-language, rather than heard. This article provides a partial review of these studies, taking a broad theoretical position from which these particular recency phenomena are approached as possible exceptions, to a general theory according to which recency is due to temporal distinctiveness. Much of the fresh evidence reviewed is of a somewhat preliminary nature and it is as yet unexplained by any theory of memory. The need for additional, converging experimental tests is obvious; so too is the need for further theoretical development. Several alternative theoretical resolutions are mentioned, including the possibility that enhanced recency may reflect movement, from sequentially occurring stimulus features, and the suggestion that it may be associated with the primary linguistic mode of the individuals concerned. But special weight is attached to the conjecture that all these recency phenomena might be accounted for in terms of distinctiveness or discriminability. On this view, the enhanced recency effects observed with certain modes, including the auditory mode, are attributed to items possessing greater temporal discriminability in those modes.

  16. Environmental externalities related to power production on biogas and natural gas based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Nielsen, Per Sieverts; Ibsen, Liselotte Schleisner

    1998-01-01

    This paper assesses the environmental impacts and external costs from selected electricity generation systems in Denmark. The assessment is carried out as part of the ExternE National Implementation, which is the second phase of the ExternE project and involves case studies from all Western...... European countries. The project use a “bottom-up” methodology to evaluate the external costs associated with a wide range of different fuel cycles. The project has identified priority impacts, where most are impacts from air emissions. Externalities due to atmospheric emissions are calculated through...

  17. Detailed sensory memory, sloppy working memory.

    Science.gov (United States)

    Sligte, Ilja G; Vandenbroucke, Annelinde R E; Scholte, H Steven; Lamme, Victor A F

    2010-01-01

    Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity limits and progressively longer lifetimes. Still, the resolution (or amount of visual detail) of each VSTM stage has remained unexplored and we test this in the present study. We presented people with a change detection task that measures the capacity of all three forms of VSTM, and we added an identification display after each change trial that required people to identify the "pre-change" object. Accurate change detection plus pre-change identification requires subjects to have a high-resolution representation of the "pre-change" object, whereas change detection or identification only can be based on the hunch that something has changed, without exactly knowing what was presented before. We observed that people maintained 6.1 objects in iconic memory, 4.6 objects in fragile VSTM, and 2.1 objects in visual working memory. Moreover, when people detected the change, they could also identify the pre-change object on 88% of the iconic memory trials, on 71% of the fragile VSTM trials and merely on 53% of the visual working memory trials. This suggests that people maintain many high-resolution representations in iconic memory and fragile VSTM, but only one high-resolution object representation in visual working memory.

  18. Dopaminergic rules of engagement for memory in Drosophila.

    Science.gov (United States)

    Kaun, Karla R; Rothenfluh, Adrian

    2017-04-01

    Dopamine is associated with a variety of conserved responses across species including locomotion, sleep, food consumption, aggression, courtship, addiction and several forms of appetitive and aversive memory. Historically, dopamine has been most prominently associated with dynamics underlying reward, punishment, or salience. Recent emerging evidence from Drosophila supports a role in all of these functions, as well as additional roles in the interplay between external sensation and internal states and forgetting of the very memories dopamine helped encode. We discuss how cell-specific resolution and manipulation are elucidating the rules of dopamine's involvement in encoding valence and memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Unilateral vestibular loss impairs external space representation.

    Directory of Open Access Journals (Sweden)

    Liliane Borel

    Full Text Available The vestibular system is responsible for a wide range of postural and oculomotor functions and maintains an internal, updated representation of the position and movement of the head in space. In this study, we assessed whether unilateral vestibular loss affects external space representation. Patients with Menière's disease and healthy participants were instructed to point to memorized targets in near (peripersonal and far (extrapersonal spaces in the absence or presence of a visual background. These individuals were also required to estimate their body pointing direction. Menière's disease patients were tested before unilateral vestibular neurotomy and during the recovery period (one week and one month after the operation, and healthy participants were tested at similar times. Unilateral vestibular loss impaired the representation of both the external space and the body pointing direction: in the dark, the configuration of perceived targets was shifted toward the lesioned side and compressed toward the contralesioned hemifield, with higher pointing error in the near space. Performance varied according to the time elapsed after neurotomy: deficits were stronger during the early stages, while gradual compensation occurred subsequently. These findings provide the first demonstration of the critical role of vestibular signals in the representation of external space and of body pointing direction in the early stages after unilateral vestibular loss.

  20. Memory systems, computation, and the second law of thermodynamics

    International Nuclear Information System (INIS)

    Wolpert, D.H.

    1992-01-01

    A memory is a physical system for transferring information form one moment in time to another, where that information concerns something external to the system itself. This paper argues on information-theoretic and statistical mechanical grounds that useful memories must be of one of two types, exemplified by memory in abstract computer programs and by memory in photographs. Photograph-type memories work by exploring a collapse of state space flow to an attractor state. (This attractor state is the open-quotes initializedclose quotes state of the memory.) The central assumption of the theory of reversible computation tells us that in any such collapsing, regardless of whether the collapsing must increase in entropy of the system. In concert with the second law, this establishes the logical necessity of the empirical observation that photograph-type memories are temporally asymmetric (they can tell us about the past but not about the future). Under the assumption that human memory is a photograph-type memory, this result also explains why we humans can remember only our past and not our future. In contrast to photo-graph-type memories, computer-type memories do not require any initialization, and therefore are not directly affected by the second law. As a result, computer memories can be of the future as easily as of the past, even if the program running on the computer is logically irreversible. This is entirely in accord with the well-known temporal reversibility of the process of computation. This paper ends by arguing that the asymmetry of the psychological arrow of time is a direct consequence of the asymmetry of human memory. With the rest of this paper, this explains, explicitly and rigorously, why the psychological and thermodynamic arrows of time are correlated with one another. 24 refs

  1. PHOSPHORUS SORPTION ISOTHERMS AND EXTERNAL ...

    African Journals Online (AJOL)

    ACSS

    Zhang et al., 2005). For instance, in strongly acidic soils with pH<5.5 and high P sorbing soils, application of rock phosphate is more effective and cheaper than using TSP (Bationo et al., 2011). Moreover, it enables determination of the external P.

  2. Hydropower externalities: a meta analysis

    NARCIS (Netherlands)

    Mattmann, M.; Logar, I.; Brouwer, R.

    2016-01-01

    This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to

  3. Matching Games with Additive Externalities

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal

    2012-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas ...

  4. Externally studentized normal midrange distribution

    Directory of Open Access Journals (Sweden)

    Ben Dêivide de Oliveira Batista

    Full Text Available ABSTRACT The distribution of externally studentized midrange was created based on the original studentization procedures of Student and was inspired in the distribution of the externally studentized range. The large use of the externally studentized range in multiple comparisons was also a motivation for developing this new distribution. This work aimed to derive analytic equations to distribution of the externally studentized midrange, obtaining the cumulative distribution, probability density and quantile functions and generating random values. This is a new distribution that the authors could not find any report in the literature. A second objective was to build an R package for obtaining numerically the probability density, cumulative distribution and quantile functions and make it available to the scientific community. The algorithms were proposed and implemented using Gauss-Legendre quadrature and the Newton-Raphson method in R software, resulting in the SMR package, available for download in the CRAN site. The implemented routines showed high accuracy proved by using Monte Carlo simulations and by comparing results with different number of quadrature points. Regarding to the precision to obtain the quantiles for cases where the degrees of freedom are close to 1 and the percentiles are close to 100%, it is recommended to use more than 64 quadrature points.

  5. Measuring Externalities in Program Evaluation

    NARCIS (Netherlands)

    Janssens, Wendy

    2005-01-01

    Impact evaluations of development programmes usually focus on a comparison of participants with a control group. However, if the programme generates externalities for non-participants such an approach will capture only part of the programme's impact. Based on a unique large-scale quantitative survey

  6. Optimal condition of memristance enhancement circuit using external voltage source

    Directory of Open Access Journals (Sweden)

    Hiroya Tanaka

    2014-05-01

    Full Text Available Memristor provides nonlinear response in the current-voltage characteristic and the memristance is modulated using an external voltage source. We point out by solving nonlinear equations that an optimal condition of the external voltage source exists for maximizing the memristance in such modulation scheme. We introduce a linear function to describe the nonlinear time response and derive an important design guideline; a constant ratio of the frequency to the amplitude of the external voltage source maximizes the memristance. The analysis completely accounts for the memristance behavior.

  7. Spatially Synchronous Extinction of Species under External Forcing

    Science.gov (United States)

    Amritkar, R. E.; Rangarajan, Govindan

    2006-06-01

    More than 99% of the species that ever existed on the surface of the Earth are now extinct and their extinction on a global scale has been a puzzle. One may think that a species under an external threat may survive in some isolated locations leading to the revival of the species. Using a general model we show that, under a common external forcing, the species with a quadratic saturation term first undergoes spatial synchronization and then extinction. The effect can be observed even when the external forcing acts only on some locations provided the dynamics contains a synchronizing term. Absence of the quadratic saturation term can help the species to avoid extinction.

  8. Gaze movements and spatial working memory in collision avoidance: a traffic intersection task

    Directory of Open Access Journals (Sweden)

    Gregor eHardiess

    2013-06-01

    Full Text Available Street crossing under traffic is an everyday activity including collision detection as well as avoidance of objects in the path of motion. Such tasks demand extraction and representation of spatio-temporal information about relevant obstacles in an optimized format. Relevant task information is extracted visually by the use of gaze movements and represented in spatial working memory. In a virtual reality traffic intersection task, subjects are confronted with a two-lane intersection where cars are appearing with different frequencies, corresponding to high and low traffic densities. Under free observation and exploration of the scenery (using unrestricted eye and head movements the overall task for the subjects was to predict the potential-of-collision (POC of the cars or to adjust an adequate driving speed in order to cross the intersection without collision (i.e., to find the free space for crossing. In a series of experiments, gaze movement parameters, task performance, and the representation of car positions within working memory at distinct time points were assessed in normal subjects as well as in neurological patients suffering from homonymous hemianopia. In the following, we review the findings of these experiments together with other studies and provide a new perspective of the role of gaze behavior and spatial memory in collision detection and avoidance, focusing on the following questions: (i which sensory variables can be identified supporting adequate collision detection? (ii How do gaze movements and working memory contribute to collision avoidance when multiple moving objects are present and (iii how do they correlate with task performance? (iv How do patients with homonymous visual field defects use gaze movements and working memory to compensate for visual field loss? In conclusion, we extend the theory of collision detection and avoidance in the case of multiple moving objects and provide a new perspective on the combined

  9. Impact of Noise and Working Memory on Speech Processing in Adults with and without ADHD

    Science.gov (United States)

    Michalek, Anne M. P.

    2012-01-01

    Auditory processing of speech is influenced by internal (i.e., attention, working memory) and external factors (i.e., background noise, visual information). This study examined the interplay among these factors in individuals with and without ADHD. All participants completed a listening in noise task, two working memory capacity tasks, and two…

  10. Memory Complaint Questionnaire performed poorly as screening tool : validation against psychometric tests and affective measures

    NARCIS (Netherlands)

    Reid, Meagan; Parkinson, Lynne; Gibson, Richard; Schofield, Peter; D'Este, Catherine; Attia, John; Tavener, Meredith; Byles, Julie

    Objective: This study examined the internal and external validity of the Memory Complaint Questionnaire (MAC-Q), a brief measure of subjective memory complaint in people with normal cognitive function. Study Design and Setting: The Study of Health Outcomes in Aircraft Maintenance Personnel was a

  11. An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios (External Review Draft)

    Science.gov (United States)

    EPA has released an external review draft entitled, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios(External Review Draft). The public comment period and the external peer-review workshop are separate processes that provide opportunities ...

  12. Memory: Enduring Traces of Perceptual and Reflective Attention

    Science.gov (United States)

    Chun, Marvin M.; Johnson, Marcia K.

    2011-01-01

    Attention and memory are typically studied as separate topics, but they are highly intertwined. Here we discuss the relation between memory and two fundamental types of attention: perceptual and reflective. Memory is the persisting consequence of cognitive activities initiated by and/or focused on external information from the environment (perceptual attention) and initiated by and/or focused on internal mental representations (reflective attention). We consider three key questions for advancing a cognitive neuroscience of attention and memory: To what extent do perception and reflection share representational areas? To what extent are the control processes that select, maintain, and manipulate perceptual and reflective information subserved by common areas and networks? During perception and reflection, to what extent are common areas responsible for binding features together to create complex, episodic memories and for reviving them later? Considering similarities and differences in perceptual and reflective attention helps integrate a broad range of findings and raises important unresolved issues. PMID:22099456

  13. External noise distinguishes attention mechanisms.

    Science.gov (United States)

    Lu, Z L; Dosher, B A

    1998-05-01

    We developed and tested a powerful method for identifying and characterizing the effect of attention on performance in visual tasks as due to signal enhancement, distractor exclusion, or internal noise suppression. Based on a noisy Perceptual Template Model (PTM) of a human observer, the method adds increasing amounts of external noise (white gaussian random noise) to the visual stimulus and observes the effect on performance of a perceptual task for attended and unattended stimuli. The three mechanisms of attention yield three "signature" patterns of performance. The general framework for characterizing the mechanisms of attention is used here to investigate the attentional mechanisms in a concurrent location-cued orientation discrimination task. Test stimuli--Gabor patches tilted slightly to the right or left--always appeared on both the left and the right of fixation, and varied independently. Observers were cued on each trial to attend to the left, the right, or evenly to both stimuli, and decide the direction of tilt of both test stimuli. For eight levels of added external noise and three attention conditions (attended, unattended, and equal), subjects' contrast threshold levels were determined. At low levels of external noise, attention affected threshold contrast: threshold contrasts for non-attended stimuli were systematically higher than for equal attention stimuli, which were, in turn, higher than for attended stimuli. Specifically, when the rms contrast of the external noise is below 10%, there is a consistent 17% elevation of contrast threshold from attended to unattended condition across all three subjects. For higher levels of external noise, attention conditions did not affect threshold contrast values at all. These strong results are characteristic of a signal enhancement, or equivalently, an internal additive noise reduction mechanism of attention.

  14. Technical basis document for external events

    International Nuclear Information System (INIS)

    OBERG, B.D.

    2003-01-01

    This document supports the Tank Farms Documented Safety Analysis and presents the technical basis for the FR-equencies of externally initiated accidents. The consequences of externally initiated events are discussed in other documents that correspond to the accident that was caused by the external event. The external events include aircraft crash, vehicle accident, range fire, and rail accident

  15. Reactivation in Working Memory : An Attractor Network Model of Free Recall

    OpenAIRE

    Lansner, Anders; Marklund, Petter; Sikström, Sverker; Nilsson, Lars-Göran

    2013-01-01

    The dynamic nature of human working memory, the general-purpose system for processing continuous input, while keeping no longer externally available information active in the background, is well captured in immediate free recall of supraspan word-lists. Free recall tasks produce several benchmark memory phenomena, like the U-shaped serial position curve, reflecting enhanced memory for early and late list items. To account for empirical data, including primacy and recency as well as contiguity...

  16. Neural evidence for a distinction between short-term memory and the focus of attention

    OpenAIRE

    Lewis-Peacock, Jarrod A; Drysdale, Andrew T; Oberauer, Klaus; Postle, Bradley R

    2012-01-01

    It is widely assumed that the short-term retention of information is accomplished via maintenance of an active neural trace. However, we demonstrate that memory can be preserved across a brief delay despite the apparent loss of sustained representations. Delay-period activity may in fact reflect the focus of attention, rather than short-term memory. We unconfounded attention and memory by causing external and internal shifts of attention away from items that were being actively retained. Mult...

  17. Susceptibility of memory consolidation during lapses in recall

    Science.gov (United States)

    Marra, Vincenzo; O’Shea, Michael; Benjamin, Paul R.; Kemenes, Ildikó

    2013-01-01

    Memories that can be recalled several hours after learning may paradoxically become inaccessible for brief periods after their formation. This raises major questions about the function of these early memory lapses in the structure of memory consolidation. These questions are difficult to investigate because of the lack of information on the precise timing of lapses. However, the use of a single-trial conditioning paradigm in Lymnaea solves this problem. Here we use electrophysiological and behavioural experiments to reveal lapses in memory recall at 30 min and 2 h post conditioning. We show that only during these lapses is consolidation of long-term memory susceptible to interruption by external disturbance. These shared time points of memory lapse and susceptibility correspond to transitions between different phases of memory that have different molecular requirements. We propose that during periods of molecular transition memory recall is weakened, allowing novel sensory cues to block the consolidation of long-term memory. PMID:23481386

  18. A mega-analysis of memory reports from eight peer-reviewed false memory implantation studies.

    Science.gov (United States)

    Scoboria, Alan; Wade, Kimberley A; Lindsay, D Stephen; Azad, Tanjeem; Strange, Deryn; Ost, James; Hyman, Ira E

    2017-02-01

    Understanding that suggestive practices can promote false beliefs and false memories for childhood events is important in many settings (e.g., psychotherapeutic, medical, and legal). The generalisability of findings from memory implantation studies has been questioned due to variability in estimates across studies. Such variability is partly due to false memories having been operationalised differently across studies and to differences in memory induction techniques. We explored ways of defining false memory based on memory science and developed a reliable coding system that we applied to reports from eight published implantation studies (N = 423). Independent raters coded transcripts using seven criteria: accepting the suggestion, elaboration beyond the suggestion, imagery, coherence, emotion, memory statements, and not rejecting the suggestion. Using this scheme, 30.4% of cases were classified as false memories and another 23% were classified as having accepted the event to some degree. When the suggestion included self-relevant information, an imagination procedure, and was not accompanied by a photo depicting the event, the memory formation rate was 46.1%. Our research demonstrates a useful procedure for systematically combining data that are not amenable to meta-analysis, and provides the most valid estimate of false memory formation and associated moderating factors within the implantation literature to date.

  19. Conversational assessment in memory clinic encounters: interactional profiling for differentiating dementia from functional memory disorders.

    Science.gov (United States)

    Jones, Danielle; Drew, Paul; Elsey, Christopher; Blackburn, Daniel; Wakefield, Sarah; Harkness, Kirsty; Reuber, Markus

    2016-01-01

    In the UK dementia is under-diagnosed, there is limited access to specialist memory clinics, and many of the patients referred to such clinics are ultimately found to have functional (non-progressive) memory disorders (FMD), rather than a neurodegenerative disorder. Government initiatives on 'timely diagnosis' aim to improve the rate and quality of diagnosis for those with dementia. This study seeks to improve the screening and diagnostic process by analysing communication between clinicians and patients during initial specialist clinic visits. Establishing differential conversational profiles could help the timely differential diagnosis of memory complaints. This study is based on video- and audio recordings of 25 initial consultations between neurologists and patients referred to a UK memory clinic. Conversation analysis was used to explore recurrent communicative practices associated with each diagnostic group. Two discrete conversational profiles began to emerge, to help differentiate between patients with dementia and functional memory complaints, based on (1) whether the patient is able to answer questions about personal information; (2) whether they can display working memory in interaction; (3) whether they are able to respond to compound questions; (4) the time taken to respond to questions; and (5) the level of detail they offer when providing an account of their memory failure experiences. The distinctive conversational profiles observed in patients with functional memory complaints on the one hand and neurodegenerative memory conditions on the other suggest that conversational profiling can support the differential diagnosis of functional and neurodegenerative memory disorders.

  20. Two measures of bilingualism in the memories of immigrants and indigenous minorities: crossover memories and codeswitching.

    Science.gov (United States)

    Altman, Carmit

    2015-04-01

    Two indices of bilingualism, crossover memories and codeswitching (CS), were explored in five groups of immigrant (English-Hebrew, Georgian-Hebrew Russian-Hebrew) and indigenous bilinguals (Arabic-Hebrew, Hebrew-English). Participants recalled memories in response to cue words and then were asked to report the language of retrieval and provide a more elaborate narrative. More memories were 'same language' memories, recalled in the language of the experimental session/cue word, but as many as 48 % of the memories were crossovers, i.e. memories reported in a language other than the language of the session/cue word. In an effort to examine the ecological validity of the self-reported language of the memories, the frequency of CS in the elaborated narratives was investigated. For the entire sample, more CS was found for self-reported crossover memories in L2 sessions. In a further analysis of CS in crossover memories, collapsed across L1 and L2 sessions, significant differences emerged between immigrants and indigenous bilinguals. Differences between immigrant and non-immigrant bilinguals are discussed in terms of the role of activation in crossover memories.

  1. Gauge subsystems, separability and robustness in autonomous quantum memories

    International Nuclear Information System (INIS)

    Sarma, Gopal; Mabuchi, Hideo

    2013-01-01

    Quantum error correction provides a fertile context for exploring the interplay of feedback control, microscopic physics and non-commutative probability. In this paper we deepen our understanding of this nexus through high-level analysis of a class of quantum memory models that we have previously proposed, which implement continuous-time versions of well-known stabilizer codes in autonomous nanophotonic circuits that require no external clocking or control. We demonstrate that the presence of the gauge subsystem in the nine-qubit Bacon–Shor code allows for a loss-tolerant layout of the corresponding nanophotonic circuit that substantially ameliorates the effects of optical propagation losses, argue that code separability allows for simplified restoration feedback protocols, and propose a modified fidelity metric for quantifying the performance of realistic quantum memories. Our treatment of these topics exploits the homogeneous modeling framework of autonomous nanophotonic circuits, but the key ideas translate to the traditional setting of discrete time, measurement-based quantum error correction. (paper)

  2. Memory vs memory-like: The different facets of CD8+ T-cell memory in HCV infection.

    Science.gov (United States)

    Hofmann, Maike; Wieland, Dominik; Pircher, Hanspeter; Thimme, Robert

    2018-05-01

    Memory CD8 + T cells are essential in orchestrating protection from re-infection. Hallmarks of virus-specific memory CD8 + T cells are the capacity to mount recall responses with rapid induction of effector cell function and antigen-independent survival. Growing evidence reveals that even chronic infection does not preclude virus-specific CD8 + T-cell memory formation. However, whether this kind of CD8 + T-cell memory that is established during chronic infection is indeed functional and provides protection from re-infection is still unclear. Human chronic hepatitis C virus infection represents a unique model system to study virus-specific CD8 + T-cell memory formation during and after cessation of persisting antigen stimulation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Prospective memory, working memory, retrospective memory and self-rated memory performance in persons with intellectual disability

    OpenAIRE

    Levén, Anna; Lyxell, Björn; Andersson, Jan; Danielsson, Henrik; Rönnberg, Jerker

    2008-01-01

    The purpose of the present study was to examine the relationship between prospective memory, working memory, retrospective memory and self-rated memory capacity in adults with and without intellectual disability. Prospective memory was investigated by means of a picture-based task. Working memory was measured as performance on span tasks. Retrospective memory was scored as recall of subject performed tasks. Self-ratings of memory performance were based on the prospective and retrospective mem...

  4. Self-grounding visual, auditory and olfactory autobiographical memories.

    Science.gov (United States)

    Knez, Igor; Ljunglöf, Louise; Arshamian, Artin; Willander, Johan

    2017-07-01

    Given that autobiographical memory provides a cognitive foundation for the self, we investigated the relative importance of visual, auditory and olfactory autobiographical memories for the self. Thirty subjects, with a mean age of 35.4years, participated in a study involving a three×three within-subject design containing nine different types of autobiographical memory cues: pictures, sounds and odors presented with neutral, positive and negative valences. It was shown that visual compared to auditory and olfactory autobiographical memories involved higher cognitive and emotional constituents for the self. Furthermore, there was a trend showing positive autobiographical memories to increase their proportion to both cognitive and emotional components of the self, from olfactory to auditory to visually cued autobiographical memories; but, yielding a reverse trend for negative autobiographical memories. Finally, and independently of modality, positive affective states were shown to be more involved in autobiographical memory than negative ones. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. 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...

  6. Auditory and visual memory in musicians and nonmusicians.

    Science.gov (United States)

    Cohen, Michael A; Evans, Karla K; Horowitz, Todd S; Wolfe, Jeremy M

    2011-06-01

    Numerous studies have shown that musicians outperform nonmusicians on a variety of tasks. Here we provide the first evidence that musicians have superior auditory recognition memory for both musical and nonmusical stimuli, compared to nonmusicians. However, this advantage did not generalize to the visual domain. Previously, we showed that auditory recognition memory is inferior to visual recognition memory. Would this be true even for trained musicians? We compared auditory and visual memory in musicians and nonmusicians using familiar music, spoken English, and visual objects. For both groups, memory for the auditory stimuli was inferior to memory for the visual objects. Thus, although considerable musical training is associated with better musical and nonmusical auditory memory, it does not increase the ability to remember sounds to the levels found with visual stimuli. This suggests a fundamental capacity difference between auditory and visual recognition memory, with a persistent advantage for the visual domain.

  7. Taste aversion memory reconsolidation is independent of its retrieval.

    Science.gov (United States)

    Rodriguez-Ortiz, Carlos J; Balderas, Israela; Garcia-DeLaTorre, Paola; Bermudez-Rattoni, Federico

    2012-10-01

    Reconsolidation refers to the destabilization/re-stabilization memory process upon its activation. However, the conditions needed to undergo reconsolidation, as well as its functional significance is quite unclear and a matter of intense investigation. Even so, memory retrieval is held as requisite to initiate reconsolidation. Therefore, in the present work we examined whether transient pharmacological disruption of memory retrieval impedes reconsolidation of stored memory in the widely used associative conditioning task, taste aversion. We found that AMPA receptors inhibition in the amygdala impaired retrieval of taste aversion memory. Furthermore, AMPA receptors blockade impeded retrieval regardless of memory strength. However, inhibition of retrieval did not affect anisomycin-mediated disruption of reconsolidation. These results indicate that retrieval is a dispensable condition to undergo reconsolidation and provide evidence of molecular dissociation between retrieval and activation of memory in the non-declarative memory model taste aversion. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Partitioned key-value store with atomic memory operations

    Energy Technology Data Exchange (ETDEWEB)

    Bent, John M.; Faibish, Sorin; Grider, Gary

    2017-02-07

    A partitioned key-value store is provided that supports atomic memory operations. A server performs a memory operation in a partitioned key-value store by receiving a request from an application for at least one atomic memory operation, the atomic memory operation comprising a memory address identifier; and, in response to the atomic memory operation, performing one or more of (i) reading a client-side memory location identified by the memory address identifier and storing one or more key-value pairs from the client-side memory location in a local key-value store of the server; and (ii) obtaining one or more key-value pairs from the local key-value store of the server and writing the obtained one or more key-value pairs into the client-side memory location identified by the memory address identifier. The server can perform functions obtained from a client-side memory location and return a result to the client using one or more of the atomic memory operations.

  9. Joint effects of emotion and color on memory.

    Science.gov (United States)

    Kuhbandner, Christof; Pekrun, Reinhard

    2013-06-01

    Numerous studies have shown that memory is enhanced for emotionally negative and positive information relative to neutral information. We examined whether emotion-induced memory enhancement is influenced by low-level perceptual attributes such as color. Because in everyday life red is often used as a warning signal, whereas green signals security, we hypothesized that red might enhance memory for negative information and green memory for positive information. To capture the signaling function of colors, we measured memory for words standing out from the context by color, and manipulated the color and emotional significance of the outstanding words. Making words outstanding by color strongly enhanced memory, replicating the well-known von Restorff effect. Furthermore, memory for colored words was further increased by emotional significance, replicating the memory-enhancing effect of emotion. Most intriguingly, the effects of emotion on memory additionally depended on color type. Red strongly increased memory for negative words, whereas green strongly increased memory for positive words. These findings provide the first evidence that emotion-induced memory enhancement is influenced by color and demonstrate that different colors can have different functions in human memory.

  10. Neural mechanism underlying autobiographical memory modulated by remoteness and emotion

    Science.gov (United States)

    Ge, Ruiyang; Fu, Yan; Wang, DaHua; Yao, Li; Long, Zhiying

    2012-03-01

    Autobiographical memory is the ability to recollect past events from one's own life. Both emotional tone and memory remoteness can influence autobiographical memory retrieval along the time axis of one's life. Although numerous studies have been performed to investigate brain regions involved in retrieving processes of autobiographical memory, the effect of emotional tone and memory age on autobiographical memory retrieval remains to be clarified. Moreover, whether the involvement of hippocampus in consolidation of autobiographical events is time dependent or independent has been controversial. In this study, we investigated the effect of memory remoteness (factor1: recent and remote) and emotional valence (factor2: positive and negative) on neural correlates underlying autobiographical memory by using functional magnetic resonance imaging (fMRI) technique. Although all four conditions activated some common regions known as "core" regions in autobiographical memory retrieval, there are some other regions showing significantly different activation for recent versus remote and positive versus negative memories. In particular, we found that bilateral hippocampal regions were activated in the four conditions regardless of memory remoteness and emotional valence. Thus, our study confirmed some findings of previous studies and provided further evidence to support the multi-trace theory which believes that the role of hippocampus involved in autobiographical memory retrieval is time-independent and permanent in memory consolidation.

  11. Study of self-compliance behaviors and internal filament characteristics in intrinsic SiOx-based resistive switching memory

    International Nuclear Information System (INIS)

    Chang, Yao-Feng; Zhou, Fei; Chen, Ying-Chen; Lee, Jack C.; Fowler, Burt

    2016-01-01

    Self-compliance characteristics and reliability optimization are investigated in intrinsic unipolar silicon oxide (SiO x )-based resistive switching (RS) memory using TiW/SiO x /TiW device structures. The program window (difference between SET voltage and RESET voltage) is dependent on external series resistance, demonstrating that the SET process is due to a voltage-triggered mechanism. The program window has been optimized for program/erase disturbance immunity and reliability for circuit-level applications. The SET and RESET transitions have also been characterized using a dynamic conductivity method, which distinguishes the self-compliance behavior due to an internal series resistance effect (filament) in SiO x -based RS memory. By using a conceptual “filament/resistive gap (GAP)” model of the conductive filament and a proton exchange model with appropriate assumptions, the internal filament resistance and GAP resistance can be estimated for high- and low-resistance states (HRS and LRS), and are found to be independent of external series resistance. Our experimental results not only provide insights into potential reliability issues but also help to clarify the switching mechanisms and device operating characteristics of SiO x -based RS memory

  12. Main Memory DBMS

    NARCIS (Netherlands)

    P.A. Boncz (Peter); L. Liu (Lei); M. Tamer Özsu

    2008-01-01

    htmlabstractA main memory database system is a DBMS that primarily relies on main memory for computer data storage. In contrast, normal database management systems employ hard disk based persisntent storage.

  13. Coping with Memory Loss

    Science.gov (United States)

    ... Consumers Home For Consumers Consumer Updates Coping With Memory Loss Share Tweet Linkedin Pin it More sharing ... be evaluated by a health professional. What Causes Memory Loss? Anything that affects cognition—the process of ...

  14. Memory and Aging

    Science.gov (United States)

    Memory and Aging Losing keys, misplacing a wallet, or forgetting someone’s name are common experiences. But for people nearing or over age 65, such memory lapses can be frightening. They wonder if they ...

  15. Tracing Cultural Memory

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    by their encounters – to address a question that thirty years of ground - breaking research into memory has not yet sufficiently answered: What can we learn about the dynamics of cultural memory by examining mundane accounts of touristic encounters with sites of memory? From Blaavand Beach in Western Denmark......We encounter, relate to and make use of our past and that of others in multifarious and increasingly mobile ways. Tourism is one of the main paths for encountering sites of memory. This thesis examines tourists’ creative appropriations of sites of memory – the objects and future memories inspired...... of memory. They highlight the role of mundane uses of the past and indicate the need for cross - disciplinary research on the visual and on memory...

  16. Practice Bulletin No. 161: External Cephalic Version.

    Science.gov (United States)

    2016-02-01

    In the United States, there is a widespread belief that the overall cesarean delivery rate is higher than necessary. Efforts are being directed toward decreasing the number of these procedures, in part by encouraging physicians to make changes in their management practices. Because breech presentations are associated with a high rate of cesarean delivery, there is renewed interest in techniques such as external cephalic version (ECV) and vaginal breech delivery. The purpose of this document is to provide information about ECV by summarizing the relevant evidence presented in published studies and to make recommendations regarding its use in obstetric practice.

  17. External RNA Controls Consortium Beta Version Update.

    Science.gov (United States)

    Lee, Hangnoh; Pine, P Scott; McDaniel, Jennifer; Salit, Marc; Oliver, Brian

    2016-01-01

    Spike-in RNAs are valuable controls for a variety of gene expression measurements. The External RNA Controls Consortium developed test sets that were used in a number of published reports. Here we provide an authoritative table that summarizes, updates, and corrects errors in the test version that ultimately resulted in the certified Standard Reference Material 2374. We have noted existence of anti-sense RNA controls in the material, corrected sub-pool memberships, and commented on control RNAs that displayed inconsistent behavior.

  18. Structural adhesives for missile external protection material

    Science.gov (United States)

    Banta, F. L.; Garzolini, J. A.

    1981-07-01

    Two basic rubber materials are examined as possible external substrate protection materials (EPM) for missiles. The analysis provided a data base for selection of the optimum adhesives which are compatible with the substrate, loads applied and predicted bondline temperatures. Under the test conditions, EA934/NA was found to be the optimum adhesive to bond VAMAC 2273 and/or NBR/EPDM 9969A to aluminum substrate. The optimum adhesive for composite structures was EA956. Both of these adhesives are two-part epoxy systems with a pot life of approximately two hours. Further research is suggested on field repair criteria, nuclear hardness and survivability effects on bondline, and ageing effects.

  19. Does overgeneral autobiographical memory result from poor memory for task instructions?

    Science.gov (United States)

    Yanes, Paula K; Roberts, John E; Carlos, Erica L

    2008-10-01

    Considerable previous research has shown that retrieval of overgeneral autobiographical memories (OGM) is elevated among individuals suffering from various emotional disorders and those with a history of trauma. Although previous theories suggest that OGM serves the function of regulating acute negative affect, it is also possible that OGM results from difficulties in keeping the instruction set for the Autobiographical Memory Test (AMT) in working memory, or what has been coined "secondary goal neglect" (Dalgleish, 2004). The present study tested whether OGM is associated with poor memory for the task's instruction set, and whether an instruction set reminder would improve memory specificity over repeated trials. Multilevel modelling data-analytic techniques demonstrated a significant relationship between poor recall of instruction set and probability of retrieving OGMs. Providing an instruction set reminder for the AMT relative to a control task's instruction set improved memory specificity immediately afterward.

  20. Emotional Memory Persists Longer than Event Memory

    Science.gov (United States)

    Kuriyama, Kenichi; Soshi, Takahiro; Fujii, Takeshi; Kim, Yoshiharu

    2010-01-01

    The interaction between amygdala-driven and hippocampus-driven activities is expected to explain why emotion enhances episodic memory recognition. However, overwhelming behavioral evidence regarding the emotion-induced enhancement of immediate and delayed episodic memory recognition has not been obtained in humans. We found that the recognition…

  1. Destination memory in Alzheimer's Disease: when I imagine telling Ronald Reagan about Paris.

    Science.gov (United States)

    El Haj, Mohamad; Postal, Virginie; Allain, Philippe

    2013-01-01

    Destination memory refers to remembering the destination of information that people output. This present paper establishes a new distinction between external and internal processes within this memory system for both normal aging and Alzheimer's Disease (AD). Young adults, older adults, and mild AD patients were asked either to tell facts (i.e., external destination memory condition) or to imagine telling facts (i.e., internal destination memory condition) to pictures of famous people. The experiment established three major findings. First, the destination memory performance of the AD patients was significantly poorer than that of older adults, which in turn was poorer than that of the young adults. Furthermore, internal destination processes were more prone to being forgotten than external destination memory processes. In other words, participants had more difficulty in remembering whether they had previously imagined telling the facts to the pictures or not (i.e., imagined condition) than in remembering whether they had previously told the facts to the pictures or not (i.e., enacted condition). Second, significant correlations were detected between performances on destination memory and several executive measures such as the Stroop, the Plus-Minus and the Binding tasks. Third, among the executive measures, regression analyses showed that performance on the Stroop task was a main factor in explaining variance in destination memory performance. Our findings reflect the difficulty in remembering the destination of internally generated information. They also demonstrate the involvement of inhibitory processes in destination memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. 'arbiter' of the faculties inferior to it, and consequently in a position to pass judgment on them. So just like the inner man is the judge of the sensations that the outer man provides, the different faculties of the mind can be hierarchically organized so that each stage is a judge of the inferior stage. Thus, at the lowest level or stage of the mind, the senses perceive the external bodies. At the next level is what Augustine calls the 'inner sense' which enables us to become aware that the information we receive from our various senses come from a common external source, and which also lets us know when one of our senses is not working properly. According to Michael Mendelson, "[i]n both of these respects, the inner sense bears an organizational and criterial relation to the senses, not only combining the information of the senses, but passing judgment on the results of this synthesis." (Mendelson 2000, section 6). Above the inner sense there is reason, understood as the capability for deductive knowledge, which allows the mind to recognize necessary truths. On this Mendelson writes: "Understood in this austere sense, i.e. in terms of the mind's ability to recognize logical necessity, reason is not merely one instrument among many; instead, it becomes the means whereby the human soul comes into contact with truths that are devoid of the mutability afflicting the objects of the senses." (ibid.) Reason is not, however, the highest level in Augustine's proposed hierarchy, since it must comport with a higher normative standard. This ultimate standard is truth (Confessions VII.17), and, as mentioned earlier, Augustine identifies God with truth. Thus Augustine's theory of mind adequately accommodates the idea that God is the judge to which man must respond, since that is only another way of saying that truth is the normative standard to which reason must aspire. IV. Three functions of memory Returning to the topic of memory, I think three faculties or functions of the mind

    OpenAIRE

    Roberto Parra Dorantes

    2017-01-01

    The main objective of this paper is to argue that Augustine’s analysis of the concept of memory in Confessions, Book X, would greatly benefit from the hierarchical argumentative and explanatory schema he himself employs in other works to discuss the relation between the senses, the inner sense, and reason in perception. A brief overview of Augustine’s account of memory in the Confessions is presented, followed by a discussion of two argumentative and explanatory schemata Augustine often emplo...

  3. A Return to the "Treasure-House of Invention": Memory in the Composition Classroom.

    Science.gov (United States)

    Cypert, Rick

    1989-01-01

    Considers how memory contributes to a writer's developing capacity for self-expression. Notes that modern applications of classical memory ("memoria verborum"/natural memory and "memoria rerum"/artificial memory) enable students to generate details that flesh out their texts as well as provide meaning to those texts. (MM)

  4. Fragile visual short-term memory is an object-based and location-specific store

    NARCIS (Netherlands)

    Pinto, Y.; Sligte, I.G.; Shapiro, K.L.; Lamme, V.A.F.

    2013-01-01

    Fragile visual short-term memory (FM) is a recently discovered form of visual short-term memory. Evidence suggests that it provides rich and high-capacity storage, like iconic memory, yet it exists, without interference, almost as long as visual working memory. In the present study, we sought to

  5. The Sensory Nature of Episodic Memory: Sensory Priming Effects Due to Memory Trace Activation

    Science.gov (United States)

    Brunel, Lionel; Labeye, Elodie; Lesourd, Mathieu; Versace, Remy

    2009-01-01

    The aim of this study was to provide evidence that memory and perceptual processing are underpinned by the same mechanisms. Specifically, the authors conducted 3 experiments that emphasized the sensory aspect of memory traces. They examined their predictions with a short-term priming paradigm based on 2 distinct phases: a learning phase consisting…

  6. Memory Indexing: A Novel Method for Tracing Memory Processes in Complex Cognitive Tasks

    Science.gov (United States)

    Renkewitz, Frank; Jahn, Georg

    2012-01-01

    We validate an eye-tracking method applicable for studying memory processes in complex cognitive tasks. The method is tested with a task on probabilistic inferences from memory. It provides valuable data on the time course of processing, thus clarifying previous results on heuristic probabilistic inference. Participants learned cue values of…

  7. Congenital blindness improves semantic and episodic memory.

    Science.gov (United States)

    Pasqualotto, Achille; Lam, Jade S Y; Proulx, Michael J

    2013-05-01

    Previous studies reported that congenitally blind people possess superior verb-generation skills. Here we tested the impact of blindness on capacity and the fidelity of semantic memory by using a false memory paradigm. In the Deese-Roediger-McDermott paradigm, participants study lists of words that are all semantically related to a lure that is not presented. Subsequently, participants frequently recall the missing lure. We found that congenitally blind participants have enhanced memory performance for recalling the presented words and reduced false memories for the lure. The dissociation of memory capacity and fidelity provides further evidence for enhanced verbal ability in the blind, supported by their broader structural and functional brain reorganisation. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Track recognition with an associative pattern memory

    International Nuclear Information System (INIS)

    Bok, H.W. den; Visschers, J.L.; Borgers, A.J.; Lourens, W.

    1991-01-01

    Using Programmable Gate Arrays (PGAs), a prototype for a fast Associative Pattern Memory module has been realized. The associative memory performs the recognition of tracks within the hadron detector data acquisition system at NIKHEF-K. The memory matches the detector state with a set of 24 predefined tracks to identify the particle tracks that occur during an event. This information enables the trigger hardware to classify and select or discriminate the event. Mounted on a standard size (6U) VME board, several PGAs together form an associative memory. The internal logic architecture of the Gate Array is used in such a way as to minimize signal propagation delay. The memory cells, containing a binary representation of the particle tracks, are dynamically loadable through a VME bus interface, providing a high level of flexibility. The hadron detector and its readout system are briefly described and our track representation method is presented. Results from measurements under experimental conditions are discussed. (orig.)

  9. Distributed-Memory Fast Maximal Independent Set

    Energy Technology Data Exchange (ETDEWEB)

    Kanewala Appuhamilage, Thejaka Amila J.; Zalewski, Marcin J.; Lumsdaine, Andrew

    2017-09-13

    The Maximal Independent Set (MIS) graph problem arises in many applications such as computer vision, information theory, molecular biology, and process scheduling. The growing scale of MIS problems suggests the use of distributed-memory hardware as a cost-effective approach to providing necessary compute and memory resources. Luby proposed four randomized algorithms to solve the MIS problem. All those algorithms are designed focusing on shared-memory machines and are analyzed using the PRAM model. These algorithms do not have direct efficient distributed-memory implementations. In this paper, we extend two of Luby’s seminal MIS algorithms, “Luby(A)” and “Luby(B),” to distributed-memory execution, and we evaluate their performance. We compare our results with the “Filtered MIS” implementation in the Combinatorial BLAS library for two types of synthetic graph inputs.

  10. Memory for color reactivates color processing region.

    Science.gov (United States)

    Slotnick, Scott D

    2009-11-25

    Memory is thought to be constructive in nature, where features processed in different cortical regions are synthesized during retrieval. In an effort to support this constructive memory framework, the present functional magnetic resonance imaging study assessed whether memory for color reactivated color processing regions. During encoding, participants were presented with colored and gray abstract shapes. During retrieval, old and new shapes were presented in gray and participants responded 'old-colored', 'old-gray', or 'new'. Within color perception regions, color memory related activity was observed in the left fusiform gyrus, adjacent to the collateral sulcus. A retinotopic mapping analysis indicated this activity occurred within color processing region V8. The present feature specific evidence provides compelling support for a constructive view of memory.

  11. False memories for dissonance inducing events.

    Science.gov (United States)

    Rodriguez, Dario N; Strange, Deryn

    2015-01-01

    Memories serve as a "database" of the self and people often produce distorted memories that support their self-concepts. One, surprisingly untested, possibility is that cognitive dissonance may be one mechanism by which people may misremember their past. We tested this hypothesis using an induced-compliance paradigm: participants either chose or were forced to write a counterattitudinal essay supporting a tuition increase and were afforded the opportunity to reduce dissonance via attitude shift or denial of responsibility. They then reported their memories for the experimental instructions and their initial attitudes (assessed two days prior to the laboratory session). Participants who chose to write the essay exhibited the predicted attitude-shift effect, and were more likely to misremember their initial attitudes and the experimental instruction than those who were forced to write the essay. Overall, our results provide evidence that cognitive dissonance may yield memory distortion, filling a significant gap in the motivated cognition and memory literatures.

  12. A Shared Scratchpad Memory with Synchronization Support

    DEFF Research Database (Denmark)

    Hansen, Henrik Enggaard; Maroun, Emad Jacob; Kristensen, Andreas Toftegaard

    2017-01-01

    Multicore processors usually communicate via shared memory, which is backed up by a shared level 2 cache and a cache coherence protocol. However, this solution is not a good fit for real-time systems, where we need to provide tight guarantees on execution and memory access times. In this paper, we...... propose a shared scratchpad memory as a time-predictable communication and synchronization structure, instead of the level 2 cache. The shared on-chip memory is accessed via a time division multiplexing arbiter, isolating the execution time of load and store instructions between processing cores....... Furthermore, the arbiter supports an extended time slot where an atomic load and store instruction can be executed to implement synchronization primitives. In the evaluation we show that a shared scratchpad memory is an efficient communication structure for a small number of processors; in our setup, 9 cores...

  13. Dynamic memory management for embedded systems

    CERN Document Server

    Atienza Alonso, David; Poucet, Christophe; Peón-Quirós, Miguel; Bartzas, Alexandros; Catthoor, Francky; Soudris, Dimitrios

    2015-01-01

    This book provides a systematic and unified methodology, including basic principles and reusable processes, for dynamic memory management (DMM) in embedded systems.  The authors describe in detail how to design and optimize the use of dynamic memory in modern, multimedia and network applications, targeting the latest generation of portable embedded systems, such as smartphones. Coverage includes a variety of design and optimization topics in electronic design automation of DMM, from high-level software optimization to microarchitecture-level hardware support. The authors describe the design of multi-layer dynamic data structures for the final memory hierarchy layers of the target portable embedded systems and how to create a low-fragmentation, cost-efficient, dynamic memory management subsystem out of configurable components for the particular memory allocation and de-allocation patterns for each type of application.  The design methodology described in this book is based on propagating constraints among de...

  14. Glucocorticoids in the prefrontal cortex enhance memory consolidation and impair working memory by a common neural mechanism

    Science.gov (United States)

    Barsegyan, Areg; Mackenzie, Scott M.; Kurose, Brian D.; McGaugh, James L.; Roozendaal, Benno

    2010-01-01

    It is well established that acute administration of adrenocortical hormones enhances the consolidation of memories of emotional experiences and, concurrently, impairs working memory. These different glucocorticoid effects on these two memory functions have generally been considered to be independently regulated processes. Here we report that a glucocorticoid receptor agonist administered into the medial prefrontal cortex (mPFC) of male Sprague-Dawley rats both enhances memory consolidation and impairs working memory. Both memory effects are mediated by activation of a membrane-bound steroid receptor and depend on noradrenergic activity within the mPFC to increase levels of cAMP-dependent protein kinase. These findings provide direct evidence that glucocorticoid effects on both memory consolidation and working memory share a common neural influence within the mPFC. PMID:20810923

  15. Music, memory and emotion

    Science.gov (United States)

    Jäncke, Lutz

    2008-01-01

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory. PMID:18710596

  16. Saving Malta's music memory

    OpenAIRE

    Sant, Toni

    2013-01-01

    Maltese music is being lost. Along with it Malta loses its culture, way of life, and memories. Dr Toni Sant is trying to change this trend through the Malta Music Memory Project (M3P) http://www.um.edu.mt/think/saving-maltas-music-memory-2/

  17. Associative Memory Acceptors.

    Science.gov (United States)

    Card, Roger

    The properties of an associative memory are examined in this paper from the viewpoint of automata theory. A device called an associative memory acceptor is studied under real-time operation. The family "L" of languages accepted by real-time associative memory acceptors is shown to properly contain the family of languages accepted by one-tape,…

  18. Generation and Context Memory

    Science.gov (United States)

    Mulligan, Neil W.; Lozito, Jeffrey P.; Rosner, Zachary A.

    2006-01-01

    Generation enhances memory for occurrence but may not enhance other aspects of memory. The present study further delineates the negative generation effect in context memory reported in N. W. Mulligan (2004). First, the negative generation effect occurred for perceptual attributes of the target item (its color and font) but not for extratarget…

  19. Music, memory and emotion.

    Science.gov (United States)

    Jäncke, Lutz

    2008-08-08

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory.

  20. A light writable microfluidic "flash memory": optically addressed actuator array with latched operation for microfluidic applications.

    Science.gov (United States)

    Hua, Zhishan; Pal, Rohit; Srivannavit, Onnop; Burns, Mark A; Gulari, Erdogan

    2008-03-01

    This paper presents a novel optically addressed microactuator array (microfluidic "flash memory") with latched operation. Analogous to the address-data bus mediated memory address protocol in electronics, the microactuator array consists of individual phase-change based actuators addressed by localized heating through focused light patterns (address bus), which can be provided by a modified projector or high power laser pointer. A common pressure manifold (data bus) for the entire array is used to generate large deflections of the phase change actuators in the molten phase. The use of phase change material as the working media enables latched operation of the actuator array. After the initial light "writing" during which the phase is temporarily changed to molten, the actuated status is self-maintained by the solid phase of the actuator without power and pressure inputs. The microfluidic flash memory can be re-configured by a new light illumination pattern and common pressure signal. The proposed approach can achieve actuation of arbitrary units in a large-scale array without the need for complex external equipment such as solenoid valves and electrical modules, which leads to significantly simplified system implementation and compact system size. The proposed work therefore provides a flexible, energy-efficient, and low cost multiplexing solution for microfluidic applications based on physical displacements. As an example, the use of the latched microactuator array as "normally closed" or "normally open" microvalves is demonstrated. The phase-change wax is fully encapsulated and thus immune from contamination issues in fluidic environments.