WorldWideScience

Sample records for short-term regulatory mechanisms

  1. Short-term mechanisms influencing volumetric brain dynamics

    Directory of Open Access Journals (Sweden)

    Nikki Dieleman

    2017-01-01

    Full Text Available With the use of magnetic resonance imaging (MRI and brain analysis tools, it has become possible to measure brain volume changes up to around 0.5%. Besides long-term brain changes caused by atrophy in aging or neurodegenerative disease, short-term mechanisms that influence brain volume may exist. When we focus on short-term changes of the brain, changes may be either physiological or pathological. As such determining the cause of volumetric dynamics of the brain is essential. Additionally for an accurate interpretation of longitudinal brain volume measures by means of neurodegeneration, knowledge about the short-term changes is needed. Therefore, in this review, we discuss the possible mechanisms influencing brain volumes on a short-term basis and set-out a framework of MRI techniques to be used for volumetric changes as well as the used analysis tools. 3D T1-weighted images are the images of choice when it comes to MRI of brain volume. These images are excellent to determine brain volume and can be used together with an analysis tool to determine the degree of volume change. Mechanisms that decrease global brain volume are: fluid restriction, evening MRI measurements, corticosteroids, antipsychotics and short-term effects of pathological processes like Alzheimer's disease, hypertension and Diabetes mellitus type II. Mechanisms increasing the brain volume include fluid intake, morning MRI measurements, surgical revascularization and probably medications like anti-inflammatory drugs and anti-hypertensive medication. Exercise was found to have no effect on brain volume on a short-term basis, which may imply that dehydration caused by exercise differs from dehydration by fluid restriction. In the upcoming years, attention should be directed towards studies investigating physiological short-term changes within the light of long-term pathological changes. Ultimately this may lead to a better understanding of the physiological short-term effects of

  2. Short-term mechanisms influencing volumetric brain dynamics

    NARCIS (Netherlands)

    Dieleman, Nikki; Koek, Huiberdina L.; Hendrikse, Jeroen

    2017-01-01

    With the use of magnetic resonance imaging (MRI) and brain analysis tools, it has become possible to measure brain volume changes up to around 0.5%. Besides long-term brain changes caused by atrophy in aging or neurodegenerative disease, short-term mechanisms that influence brain volume may exist.

  3. Holding Multiple Items in Short Term Memory: A Neural Mechanism

    Science.gov (United States)

    Rolls, Edmund T.; Dempere-Marco, Laura; Deco, Gustavo

    2013-01-01

    Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging. PMID:23613789

  4. Holding multiple items in short term memory: a neural mechanism.

    Directory of Open Access Journals (Sweden)

    Edmund T Rolls

    Full Text Available Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging.

  5. Holding multiple items in short term memory: a neural mechanism.

    Science.gov (United States)

    Rolls, Edmund T; Dempere-Marco, Laura; Deco, Gustavo

    2013-01-01

    Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging.

  6. Neural circuit mechanisms of short-term memory

    Science.gov (United States)

    Goldman, Mark

    Memory over time scales of seconds to tens of seconds is thought to be maintained by neural activity that is triggered by a memorized stimulus and persists long after the stimulus is turned off. This presents a challenge to current models of memory-storing mechanisms, because the typical time scales associated with cellular and synaptic dynamics are two orders of magnitude smaller than this. While such long time scales can easily be achieved by bistable processes that toggle like a flip-flop between a baseline and elevated-activity state, many neuronal systems have been observed experimentally to be capable of maintaining a continuum of stable states. For example, in neural integrator networks involved in the accumulation of evidence for decision making and in motor control, individual neurons have been recorded whose activity reflects the mathematical integral of their inputs; in the absence of input, these neurons sustain activity at a level proportional to the running total of their inputs. This represents an analog form of memory whose dynamics can be conceptualized through an energy landscape with a continuum of lowest-energy states. Such continuous attractor landscapes are structurally non-robust, in seeming violation of the relative robustness of biological memory systems. In this talk, I will present and compare different biologically motivated circuit motifs for the accumulation and storage of signals in short-term memory. Challenges to generating robust memory maintenance will be highlighted and potential mechanisms for ameliorating the sensitivity of memory networks to perturbations will be discussed. Funding for this work was provided by NIH R01 MH065034, NSF IIS-1208218, Simons Foundation 324260, and a UC Davis Ophthalmology Research to Prevent Blindness Grant.

  7. Short-term plasticity as a neural mechanism supporting memory and attentional functions

    OpenAIRE

    Jääskeläinen, Iiro P.; Ahveninen, Jyrki; Andermann, Mark L.; Belliveau, John W.; Raij, Tommi; Sams, Mikko

    2011-01-01

    Based on behavioral studies, several relatively distinct perceptual and cognitive functions have been defined in cognitive psychology such as sensory memory, short-term memory, and selective attention. Here, we review evidence suggesting that some of these functions may be supported by shared underlying neuronal mechanisms. Specifically, we present, based on an integrative review of the literature, a hypothetical model wherein short-term plasticity, in the form of transient center-excitatory ...

  8. Short-term plasticity as a neural mechanism supporting memory and attentional functions.

    Science.gov (United States)

    Jääskeläinen, Iiro P; Ahveninen, Jyrki; Andermann, Mark L; Belliveau, John W; Raij, Tommi; Sams, Mikko

    2011-11-08

    Based on behavioral studies, several relatively distinct perceptual and cognitive functions have been defined in cognitive psychology such as sensory memory, short-term memory, and selective attention. Here, we review evidence suggesting that some of these functions may be supported by shared underlying neuronal mechanisms. Specifically, we present, based on an integrative review of the literature, a hypothetical model wherein short-term plasticity, in the form of transient center-excitatory and surround-inhibitory modulations, constitutes a generic processing principle that supports sensory memory, short-term memory, involuntary attention, selective attention, and perceptual learning. In our model, the size and complexity of receptive fields/level of abstraction of neural representations, as well as the length of temporal receptive windows, increases as one steps up the cortical hierarchy. Consequently, the type of input (bottom-up vs. top down) and the level of cortical hierarchy that the inputs target, determine whether short-term plasticity supports purely sensory vs. semantic short-term memory or attentional functions. Furthermore, we suggest that rather than discrete memory systems, there are continuums of memory representations from short-lived sensory ones to more abstract longer-duration representations, such as those tapped by behavioral studies of short-term memory. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Rapid effects of estrogens on short-term memory: Possible mechanisms.

    Science.gov (United States)

    Paletta, Pietro; Sheppard, Paul A S; Matta, Richard; Ervin, Kelsy S J; Choleris, Elena

    2018-06-01

    Estrogens affect learning and memory through rapid and delayed mechanisms. Here we review studies on rapid effects on short-term memory. Estradiol rapidly improves social and object recognition memory, spatial memory, and social learning when administered systemically. The dorsal hippocampus mediates estrogen rapid facilitation of object, social and spatial short-term memory. The medial amygdala mediates rapid facilitation of social recognition. The three estrogen receptors, α (ERα), β (ERβ) and the G-protein coupled estrogen receptor (GPER) appear to play different roles depending on the task and brain region. Both ERα and GPER agonists rapidly facilitate short-term social and object recognition and spatial memory when administered systemically or into the dorsal hippocampus and facilitate social recognition in the medial amygdala. Conversely, only GPER can facilitate social learning after systemic treatment and an ERβ agonist only rapidly improved short-term spatial memory when given systemically or into the hippocampus, but also facilitates social recognition in the medial amygdala. Investigations into the mechanisms behind estrogens' rapid effects on short term memory showed an involvement of the extracellular signal-regulated kinase (ERK) and the phosphoinositide 3-kinase (PI3K) kinase pathways. Recent evidence also showed that estrogens interact with the neuropeptide oxytocin in rapidly facilitating social recognition. Estrogens can increase the production and/or release of oxytocin and other neurotransmitters, such as dopamine and acetylcholine. Therefore, it is possible that estrogens' rapid effects on short-term memory may occur through the regulation of various neurotransmitters, although more research is need on these interactions as well as the mechanisms of estrogens' actions on short-term memory. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Statistical mechanics of neocortical interactions. Derivation of short-term-memory capacity

    Science.gov (United States)

    Ingber, Lester

    1984-06-01

    A theory developed by the author to describe macroscopic neocortical interactions demonstrates that empirical values of chemical and electrical parameters of synaptic interactions establish several minima of the path-integral Lagrangian as a function of excitatory and inhibitory columnar firings. The number of possible minima, their time scales of hysteresis and probable reverberations, and their nearest-neighbor columnar interactions are all consistent with well-established empirical rules of human short-term memory. Thus, aspects of conscious experience are derived from neuronal firing patterns, using modern methods of nonlinear nonequilibrium statistical mechanics to develop realistic explicit synaptic interactions.

  11. An Opportunistic Routing Mechanism Combined with Long-Term and Short-Term Metrics for WMN

    Directory of Open Access Journals (Sweden)

    Weifeng Sun

    2014-01-01

    Full Text Available WMN (wireless mesh network is a useful wireless multihop network with tremendous research value. The routing strategy decides the performance of network and the quality of transmission. A good routing algorithm will use the whole bandwidth of network and assure the quality of service of traffic. Since the routing metric ETX (expected transmission count does not assure good quality of wireless links, to improve the routing performance, an opportunistic routing mechanism combined with long-term and short-term metrics for WMN based on OLSR (optimized link state routing and ETX is proposed in this paper. This mechanism always chooses the highest throughput links to improve the performance of routing over WMN and then reduces the energy consumption of mesh routers. The simulations and analyses show that the opportunistic routing mechanism is better than the mechanism with the metric of ETX.

  12. An opportunistic routing mechanism combined with long-term and short-term metrics for WMN.

    Science.gov (United States)

    Sun, Weifeng; Wang, Haotian; Piao, Xianglan; Qiu, Tie

    2014-01-01

    WMN (wireless mesh network) is a useful wireless multihop network with tremendous research value. The routing strategy decides the performance of network and the quality of transmission. A good routing algorithm will use the whole bandwidth of network and assure the quality of service of traffic. Since the routing metric ETX (expected transmission count) does not assure good quality of wireless links, to improve the routing performance, an opportunistic routing mechanism combined with long-term and short-term metrics for WMN based on OLSR (optimized link state routing) and ETX is proposed in this paper. This mechanism always chooses the highest throughput links to improve the performance of routing over WMN and then reduces the energy consumption of mesh routers. The simulations and analyses show that the opportunistic routing mechanism is better than the mechanism with the metric of ETX.

  13. Selective deficit of spatial short-term memory: Role of storage and rehearsal mechanisms.

    Science.gov (United States)

    Bonnì, Sonia; Perri, Roberta; Fadda, Lucia; Tomaiuolo, Francesco; Koch, Giacomo; Caltagirone, Carlo; Carlesimo, Giovanni Augusto

    2014-10-01

    We report the neuropsychological and MRI investigation of a patient (GP) who developed a selective impairment of spatial short-term memory (STM) following damage to the dorso-mesial areas of the right frontal lobe. We assessed in this patient spatial STM with an experimental procedure that evaluated immediate and 5-20 s delayed recall of verbal, visual and spatial stimuli. The patient scored significantly worse than normal controls on tests that required delayed recall of spatial data. This could not be ascribed to a deficit of spatial episodic long-term memory because amnesic patients performed normally on these tests. Conversely, the patient scored in the normal range on tests of immediate recall of verbal, visual and spatial data and tests of delayed recall of verbal and visual data. Comparison with a previously described patient who had a selective deficit in immediate spatial recall and an ischemic lesion that affected frontal and parietal dorso-mesial areas in the right hemisphere (Carlesimo GA, Perri R, Turriziani P, Tomaiuolo F, Caltagirone C. Remembering what but not where: independence of spatial and visual working memory in the human brain. Cortex. 2001 Sep; 37(4):519-34) suggests that the right parietal areas are involved in the short-term storage of spatial information and that the dorso-mesial regions of the right frontal underlie mechanisms for the delayed maintenance of the same data.

  14. Statistical mechanics of neocortical interactions: Path-integral evolution of short-term memory

    Science.gov (United States)

    Ingber, Lester

    1994-05-01

    Previous papers in this series of statistical mechanics of neocortical interactions (SMNI) have detailed a development from the relatively microscopic scales of neurons up to the macroscopic scales as recorded by electroencephalography (EEG), requiring an intermediate mesocolumnar scale to be developed at the scale of minicolumns (~=102 neurons) and macrocolumns (~=105 neurons). Opportunity was taken to view SMNI as sets of statistical constraints, not necessarily describing specific synaptic or neuronal mechanisms, on neuronal interactions, on some aspects of short-term memory (STM), e.g., its capacity, stability, and duration. A recently developed c-language code, pathint, provides a non-Monte Carlo technique for calculating the dynamic evolution of arbitrary-dimension (subject to computer resources) nonlinear Lagrangians, such as derived for the two-variable SMNI problem. Here, pathint is used to explicitly detail the evolution of the SMNI constraints on STM.

  15. Computational Bench Testing to Evaluate the Short-Term Mechanical Performance of a Polymeric Stent.

    Science.gov (United States)

    Bobel, A C; Petisco, S; Sarasua, J R; Wang, W; McHugh, P E

    2015-12-01

    Over the last decade, there has been a significant volume of research focussed on the utilization of biodegradable polymers such as poly-L-lactide-acid (PLLA) for applications associated with cardiovascular disease. More specifically, there has been an emphasis on upgrading current clinical shortfalls experienced with conventional bare metal stents and drug eluting stents. One such approach, the adaption of fully formed polymeric stents has led to a small number of products being commercialized. Unfortunately, these products are still in their market infancy, meaning there is a clear non-occurrence of long term data which can support their mechanical performance in vivo. Moreover, the load carry capacity and other mechanical properties essential to a fully optimized polymeric stent are difficult, timely and costly to establish. With the aim of compiling rapid and representative performance data for specific stent geometries, materials and designs, in addition to reducing experimental timeframes, Computational bench testing via finite element analysis (FEA) offers itself as a very powerful tool. On this basis, the research presented in this paper is concentrated on the finite element simulation of the mechanical performance of PLLA, which is a fully biodegradable polymer, in the stent application, using a non-linear viscous material model. Three physical stent geometries, typically used for fully polymeric stents, are selected, and a comparative study is performed in relation to their short-term mechanical performance, with the aid of experimental data. From the simulated output results, an informed understanding can be established in relation to radial strength, flexibility and longitudinal resistance, that can be compared with conventional permanent metal stent functionality, and the results show that it is indeed possible to generate a PLLA stent with comparable and sufficient mechanical performance. The paper also demonstrates the attractiveness of FEA as a tool

  16. Obesity and pregnancy: mechanisms of short term and long term adverse consequences for mother and child.

    Science.gov (United States)

    Catalano, Patrick M; Shankar, Kartik

    2017-02-08

    Obesity is the most common medical condition in women of reproductive age. Obesity during pregnancy has short term and long term adverse consequences for both mother and child. Obesity causes problems with infertility, and in early gestation it causes spontaneous pregnancy loss and congenital anomalies. Metabolically, obese women have increased insulin resistance in early pregnancy, which becomes manifest clinically in late gestation as glucose intolerance and fetal overgrowth. At term, the risk of cesarean delivery and wound complications is increased. Postpartum, obese women have an increased risk of venous thromboembolism, depression, and difficulty with breast feeding. Because 50-60% of overweight or obese women gain more than recommended by Institute of Medicine gestational weight guidelines, postpartum weight retention increases future cardiometabolic risks and prepregnancy obesity in subsequent pregnancies. Neonates of obese women have increased body fat at birth, which increases the risk of childhood obesity. Although there is no unifying mechanism responsible for the adverse perinatal outcomes associated with maternal obesity, on the basis of the available data, increased prepregnancy maternal insulin resistance and accompanying hyperinsulinemia, inflammation, and oxidative stress seem to contribute to early placental and fetal dysfunction. We will review the pathophysiology underlying these data and try to shed light on the specific underlying mechanisms. 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.

  17. Short-term changes in running mechanics and foot strike pattern after introduction to minimalistic footwear.

    Science.gov (United States)

    Willson, John D; Bjorhus, Jordan S; Williams, D S Blaise; Butler, Robert J; Porcari, John P; Kernozek, Thomas W

    2014-01-01

    Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern. To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear. A 2-week, prospective, observational study. A movement science laboratory. Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes. The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period. Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention. The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern. Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher

  18. Mechanism for optimization of signal-to-noise ratio of dopamine release based on short-term bidirectional plasticity.

    Science.gov (United States)

    Da Cunha, Claudio; McKimm, Eric; Da Cunha, Rafael M; Boschen, Suelen L; Redgrave, Peter; Blaha, Charles D

    2017-07-15

    Repeated electrical stimulation of dopamine (dopamine) fibers can cause variable effects on further dopamine release; sometimes there are short-term decreases while in other cases short-term increases have been reported. Previous studies have failed to discover what factors determine in which way dopamine neurons will respond to repeated stimulation. The aim of the present study was therefore to investigate what determines the direction and magnitude of this particular form of short-term plasticity. Fixed potential amperometry was used to measure dopamine release in the nucleus accumbens in response to two trains of electrical pulses administered to the ventral tegmental area of anesthetized mice. When the pulse trains were of equal magnitude we found that low magnitude stimulation was associated with short-term suppression and high magnitude stimulation with short-term facilitation of dopamine release. Secondly, we found that the magnitude of the second pulse train was critical for determining the sign of the plasticity (suppression or facilitation), while the magnitude of the first pulse train determined the extent to which the response to the second train was suppressed or facilitated. This form of bidirectional plasticity might provide a mechanism to enhance signal-to-noise ratio of dopamine neurotransmission. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Orienting Attention within Visual Short-Term Memory: Development and Mechanisms

    Science.gov (United States)

    Shimi, Andria; Nobre, Anna C.; Astle, Duncan; Scerif, Gaia

    2014-01-01

    How does developing attentional control operate within visual short-term memory (VSTM)? Seven-year-olds, 11-year-olds, and adults (total n = 205) were asked to report whether probe items were part of preceding visual arrays. In Experiment 1, central or peripheral cues oriented attention to the location of to-be-probed items either prior to…

  20. Selective Short-Term Memory Deficits Arise from Impaired Domain-General Semantic Control Mechanisms

    Science.gov (United States)

    Hoffman, Paul; Jefferies, Elizabeth; Ehsan, Sheeba; Hopper, Samantha; Lambon Ralph, Matthew A.

    2009-01-01

    Semantic short-term memory (STM) patients have a reduced ability to retain semantic information over brief delays but perform well on other semantic tasks; this pattern suggests damage to a dedicated buffer for semantic information. Alternatively, these difficulties may arise from mild disruption to domain-general semantic processes that have…

  1. Statistical mechanics of neocortical interactions: Constraints on 40-Hz models of short-term memory

    Science.gov (United States)

    Ingber, Lester

    1995-10-01

    Calculations presented in L. Ingber and P.L. Nunez, Phys. Rev. E 51, 5074 (1995) detailed the evolution of short-term memory in the neocortex, supporting the empirical 7+/-2 rule of constraints on the capacity of neocortical processing. These results are given further support when other recent models of 40-Hz subcycles of low-frequency oscillations are considered.

  2. Effects of aging on muscle mechanical function and muscle fiber morphology during short-term immobilization and subsequent retraining

    DEFF Research Database (Denmark)

    Hvid, Lars; Aagaard, Per; Justesen, Lene

    2010-01-01

    Very little attention has been given to the combined effects of aging and disuse as separate factors causing deterioration in muscle mechanical function. Thus the purpose of this study was to investigate the effects of 2 wk of immobilization followed by 4 wk of retraining on knee extensor muscle...... to the deleterious effects of short-term muscle disuse on muscle fiber size and rapid force capacity than YM. Furthermore, OM seems to require longer time to recover and regain rapid muscle force capacity, which may lead to a larger risk of falling in aged individuals after periods of short-term disuse....

  3. Simulation of Mechanical Processes in Gas Storage Caverns for Short-Term Energy Storage

    Science.gov (United States)

    Böttcher, Norbert; Nagel, Thomas; Kolditz, Olaf

    2015-04-01

    In recent years, Germany's energy management has started to be transferred from fossil fuels to renewable and sustainable energy carriers. Renewable energy sources such as solar and wind power are subjected by fluctuations, thus the development and extension of energy storage capacities is a priority in German R&D programs. This work is a part of the ANGUS+ Project, funded by the federal ministry of education and research, which investigates the influence of subsurface energy storage on the underground. The utilization of subsurface salt caverns as a long-term storage reservoir for fossil fuels is a common method, since the construction of caverns in salt rock is inexpensive in comparison to solid rock formations due to solution mining. Another advantage of evaporate as host material is the self-healing behaviour of salt rock, thus the cavity can be assumed to be impermeable. In the framework of short-term energy storage (hours to days), caverns can be used as gas storage reservoirs for natural or artificial fuel gases, such as hydrogen, methane, or compressed air, where the operation pressures inside the caverns will fluctuate more frequently. This work investigates the influence of changing operation pressures at high frequencies on the stability of the host rock of gas storage caverns utilizing numerical models. Therefore, we developed a coupled Thermo-Hydro-Mechanical (THM) model based on the finite element method utilizing the open-source software platform OpenGeoSys. The salt behaviour is described by well-known constitutive material models which are capable of predicting creep, self-healing, and dilatancy processes. Our simulations include the thermodynamic behaviour of gas storage process, temperature development and distribution on the cavern boundary, the deformation of the cavern geometry, and the prediction of the dilatancy zone. Based on the numerical results, optimal operation modes can be found for individual caverns, so the risk of host rock damage

  4. Effects of aging on muscle mechanical function and muscle fiber morphology during short-term immobilization and subsequent retraining

    DEFF Research Database (Denmark)

    Hvid, Lars; Aagaard, Per; Justesen, Lene

    2010-01-01

    to the deleterious effects of short-term muscle disuse on muscle fiber size and rapid force capacity than YM. Furthermore, OM seems to require longer time to recover and regain rapid muscle force capacity, which may lead to a larger risk of falling in aged individuals after periods of short-term disuse.......Very little attention has been given to the combined effects of aging and disuse as separate factors causing deterioration in muscle mechanical function. Thus the purpose of this study was to investigate the effects of 2 wk of immobilization followed by 4 wk of retraining on knee extensor muscle...... mechanical function (e.g., maximal strength and rapid force capacity) and muscle fiber morphology in 9 old (OM: 67.3 ± 1.3 yr) and 11 young healthy men (YM: 24.4 ± 0.5 yr) with comparable levels of physical activity. Following immobilization, OM demonstrated markedly larger decreases in rapid force capacity...

  5. Orienting attention within visual short-term memory: development and mechanisms.

    Science.gov (United States)

    Shimi, Andria; Nobre, Anna C; Astle, Duncan; Scerif, Gaia

    2014-01-01

    How does developing attentional control operate within visual short-term memory (VSTM)? Seven-year-olds, 11-year-olds, and adults (total n = 205) were asked to report whether probe items were part of preceding visual arrays. In Experiment 1, central or peripheral cues oriented attention to the location of to-be-probed items either prior to encoding or during maintenance. Cues improved memory regardless of their position, but younger children benefited less from cues presented during maintenance, and these benefits related to VSTM span over and above basic memory in uncued trials. In Experiment 2, cues of low validity eliminated benefits, suggesting that even the youngest children use cues voluntarily, rather than automatically. These findings elucidate the close coupling between developing visuospatial attentional control and VSTM. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

  6. Neural mechanisms of information storage in visual short-term memory.

    Science.gov (United States)

    Serences, John T

    2016-11-01

    The capacity to briefly memorize fleeting sensory information supports visual search and behavioral interactions with relevant stimuli in the environment. Traditionally, studies investigating the neural basis of visual short term memory (STM) have focused on the role of prefrontal cortex (PFC) in exerting executive control over what information is stored and how it is adaptively used to guide behavior. However, the neural substrates that support the actual storage of content-specific information in STM are more controversial, with some attributing this function to PFC and others to the specialized areas of early visual cortex that initially encode incoming sensory stimuli. In contrast to these traditional views, I will review evidence suggesting that content-specific information can be flexibly maintained in areas across the cortical hierarchy ranging from early visual cortex to PFC. While the factors that determine exactly where content-specific information is represented are not yet entirely clear, recognizing the importance of task-demands and better understanding the operation of non-spiking neural codes may help to constrain new theories about how memories are maintained at different resolutions, across different timescales, and in the presence of distracting information. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Neural Mechanisms of Information Storage in Visual Short-Term Memory

    Science.gov (United States)

    Serences, John T.

    2016-01-01

    The capacity to briefly memorize fleeting sensory information supports visual search and behavioral interactions with relevant stimuli in the environment. Traditionally, studies investigating the neural basis of visual short term memory (STM) have focused on the role of prefrontal cortex (PFC) in exerting executive control over what information is stored and how it is adaptively used to guide behavior. However, the neural substrates that support the actual storage of content-specific information in STM are more controversial, with some attributing this function to PFC and others to the specialized areas of early visual cortex that initially encode incoming sensory stimuli. In contrast to these traditional views, I will review evidence suggesting that content-specific information can be flexibly maintained in areas across the cortical hierarchy ranging from early visual cortex to PFC. While the factors that determine exactly where content-specific information is represented are not yet entirely clear, recognizing the importance of task-demands and better understanding the operation of non-spiking neural codes may help to constrain new theories about how memories are maintained at different resolutions, across different timescales, and in the presence of distracting information. PMID:27668990

  8. Neural Mechanisms Underlying Visual Short-Term Memory Gain for Temporally Distinct Objects.

    Science.gov (United States)

    Ihssen, Niklas; Linden, David E J; Miller, Claire E; Shapiro, Kimron L

    2015-08-01

    Recent research has shown that visual short-term memory (VSTM) can substantially be improved when the to-be-remembered objects are split in 2 half-arrays (i.e., sequenced) or the entire array is shown twice (i.e., repeated), rather than presented simultaneously. Here we investigate the hypothesis that sequencing and repeating displays overcomes attentional "bottlenecks" during simultaneous encoding. Using functional magnetic resonance imaging, we show that sequencing and repeating displays increased brain activation in extrastriate and primary visual areas, relative to simultaneous displays (Study 1). Passively viewing identical stimuli did not increase visual activation (Study 2), ruling out a physical confound. Importantly, areas of the frontoparietal attention network showed increased activation in repetition but not in sequential trials. This dissociation suggests that repeating a display increases attentional control by allowing attention to be reallocated in a second encoding episode. In contrast, sequencing the array poses fewer demands on control, with competition from nonattended objects being reduced by the half-arrays. This idea was corroborated by a third study in which we found optimal VSTM for sequential displays minimizing attentional demands. Importantly these results provide support within the same experimental paradigm for the role of stimulus-driven and top-down attentional control aspects of biased competition theory in setting constraints on VSTM. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. Unmasking of tracheomalacia following short-term mechanical ventilation in a patient of adult respiratory distress syndrome

    Directory of Open Access Journals (Sweden)

    Harihar V Hegde

    2012-01-01

    Full Text Available Patients with chronic obstructive pulmonary disease (COPD are susceptible to airway malacia, which may be unmasked following mechanical ventilation or tracheostomy decannulation. Dynamic imaging of central airways, a non-invasive test as effective as bronchoscopy to diagnose airway malacia, has increased the recognition of this disorder. We describe a 70-year-old woman admitted with adult respiratory distress syndrome. She had cardiorespiratory arrest on admission, from which she was successfully resuscitated. She had obesity, hypertension, diabetes mellitus, recurrent ventricular tachycardia, sarcoidosis with interstitial lung disease and COPD. She received short-term (18 days mechanical ventilation with tracheostomy and developed respiratory distress following tracheostomy decannulation.

  10. Glycogenolysis during short-term fasting in malaria and healthy subjects - the potential regulatory role of glycogen content on glycogen breakdown: a hypothesis

    NARCIS (Netherlands)

    Sprangers, F.; Thien, H. V.; Ackermans, M. T.; Endert, E.; Sauerwein, H. P.

    2004-01-01

    Background & aims: During short-term starvation ( <24h), glucose production decreases 10-20% due to a decrease in glycogenolysis. In the fed state glycogen regulates its rate of breakdown, in order to limit glycogen accumulation. Whether in the fasted state a similar mechanism exists to preserve

  11. Modeling of short-term mechanism of arterial pressure control in the cardiovascular system: object-oriented and acausal approach.

    Science.gov (United States)

    Kulhánek, Tomáš; Kofránek, Jiří; Mateják, Marek

    2014-11-01

    This letter introduces an alternative approach to modeling the cardiovascular system with a short-term control mechanism published in Computers in Biology and Medicine, Vol. 47 (2014), pp. 104-112. We recommend using abstract components on a distinct physical level, separating the model into hydraulic components, subsystems of the cardiovascular system and individual subsystems of the control mechanism and scenario. We recommend utilizing an acausal modeling feature of Modelica language, which allows model variables to be expressed declaratively. Furthermore, the Modelica tool identifies which are the dependent and independent variables upon compilation. An example of our approach is introduced on several elementary components representing the hydraulic resistance to fluid flow and the elastic response of the vessel, among others. The introduced model implementation can be more reusable and understandable for the general scientific community. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Short-term effects of positive expiratory airway pressure in patients being weaned from mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Marcelo de Mello Rieder

    2009-05-01

    Full Text Available OBJECTIVE: To investigate the feasibility and the cardiorespiratory effects of using positive expiratory airway pressure, a physiotherapeutic tool, in comparison with a T-tube, to wean patients from mechanical ventilation. METHODS/DESIGN: A prospective, randomized, cross-over study. SETTING: Two intensive care units. PATIENTS AND INTERVENTIONS: We evaluated forty patients who met weaning criteria and had been mechanically-ventilated for more than 48 hours, mean age 59 years, including 23 males. All patients were submitted to the T-tube and Expiratory Positive Airway Pressure devices, at 7 cm H2O, during a 30-minute period. Cardiorespiratory variables including work of breathing, respiratory rate (rr, peripheral oxygen saturation (SpO2, heart rate (hr, systolic, diastolic and mean arterial pressures (SAP, DAP, MAP were measured in the first and thirtieth minutes. The condition was analyzed as an entire sample set (n=40 and was also divided into subconditions: chronic obstructive pulmonary disease (n=14 and non-chronic obstructive pulmonary disease (non- chronic obstructive pulmonary disease (n=26 categories. Comparisons were made using a t-test and Analysis of Variance. The level of significance was p < 0.05. RESULTS: Our data showed an increase in work of breathing in the first and thirtieth minutes in the EPAP condition (0.86+ 0.43 and 1.02+1.3 as compared with the T-tube condition (0.25+0.26 and 0.26+0.35 (p<0.05, verified by the flow-sensor monitor (values in J/L. No statistical differences were observed when comparing the Expiratory Positive Airway Pressure and T-tube conditions with regard to cardiorespiratory measurements. The same result was observed for both chronic obstructive pulmonary disease and non- chronic obstructive pulmonary disease subconditions. CONCLUSIONS: Our study demonstrated that, in weaning patients from mechanical ventilation, the use of a fixed level of Expiratory Positive Airway Pressure caused an increase in work of

  13. Short-term saccadic adaptation in the macaque monkey: a binocular mechanism

    Science.gov (United States)

    Schultz, K. P.

    2013-01-01

    Saccadic eye movements are rapid transfers of gaze between objects of interest. Their duration is too short for the visual system to be able to follow their progress in time. Adaptive mechanisms constantly recalibrate the saccadic responses by detecting how close the landings are to the selected targets. The double-step saccadic paradigm is a common method to simulate alterations in saccadic gain. While the subject is responding to a first target shift, a second shift is introduced in the middle of this movement, which masks it from visual detection. The error in landing introduced by the second shift is interpreted by the brain as an error in the programming of the initial response, with gradual gain changes aimed at compensating the apparent sensorimotor mismatch. A second shift applied dichoptically to only one eye introduces disconjugate landing errors between the two eyes. A monocular adaptive system would independently modify only the gain of the eye exposed to the second shift in order to reestablish binocular alignment. Our results support a binocular mechanism. A version-based saccadic adaptive process detects postsaccadic version errors and generates compensatory conjugate gain alterations. A vergence-based saccadic adaptive process detects postsaccadic disparity errors and generates corrective nonvisual disparity signals that are sent to the vergence system to regain binocularity. This results in striking dynamical similarities between visually driven combined saccade-vergence gaze transfers, where the disparity is given by the visual targets, and the double-step adaptive disconjugate responses, where an adaptive disparity signal is generated internally by the saccadic system. PMID:23076111

  14. An evaluation of short-term exposures of brake mechanics to asbestos during automotive and truck brake cleaning and machining activities.

    Science.gov (United States)

    Richter, Richard O; Finley, Brent L; Paustenbach, Dennis J; Williams, Pamela R D; Sheehan, Patrick J

    2009-07-01

    Historically, the greatest contributions to airborne asbestos concentrations during brake repair work were likely due to specific, short-duration, dust-generating activities. In this paper, the available short-term asbestos air sampling data for mechanics collected during the cleaning and machining of vehicle brakes are evaluated to determine their impact on both short-term and daily exposures. The high degree of variability and lack of transparency for most of the short-term samples limit their use in reconstructing past asbestos exposures for brake mechanics. However, the data are useful in evaluating how reducing short-term, dust-generating activities reduced long-term exposures, especially for auto brake mechanics. Using the short-term dose data for grinding brake linings from these same studies, in combination with existing time-weighted average (TWA) data collected in decades after grinding was commonplace in rebuilding brake shoes, an average 8-h TWA of approximately 0.10 f/cc was estimated for auto brake mechanics that performed arc grinding of linings during automobile brake repair (in the 1960s or earlier). In the 1970s and early 1980s, a decline in machining activities led to a decrease in the 8-h TWA to approximately 0.063 f/cc. Improved cleaning methods in the late 1980s further reduced the 8-h TWA for most brake mechanics to about 0.0021 f/cc. It is noteworthy that when compared with the original OSHA excursion level, only 15 of the more than 300 short-term concentrations for brake mechanics measured during the 1970s and 1980s possibly exceeded the standard. Considering exposure duration, none of the short-term exposures were above the current OSHA excursion level.

  15. Mechanical property degradation and microstructural evolution of cast austenitic stainless steels under short-term thermal aging

    Science.gov (United States)

    Lach, Timothy G.; Byun, Thak Sang; Leonard, Keith J.

    2017-12-01

    Mechanical testing and microstructural characterization were performed on short-term thermally aged cast austenitic stainless steels (CASS) to understand the severity and mechanisms of thermal-aging degradation experienced during extended operation of light water reactor (LWR) coolant systems. Four CASS materials-CF3, CF3M, CF8, and CF8M-were thermally aged for 1500 h at 290 °C, 330 °C, 360 °C, and 400 °C. All four alloys experienced insignificant change in strength and ductility properties but a significant reduction in absorbed impact energy. The primary microstructural and compositional changes during thermal aging were spinodal decomposition of the δ-ferrite into α/α‧, precipitation of G-phase in the δ-ferrite, segregation of solute to the austenite/ferrite interphase boundary, and growth of M23C6 carbides on the austenite/ferrite interphase boundary. These changes were shown to be highly dependent on chemical composition, particularly the concentration of C and Mo, and aging temperature. The low C, high Mo CF3M alloys experienced the most spinodal decomposition and G-phase precipitation coinciding the largest reduction in impact properties.

  16. Short-term retention of visual information: Evidence in support of feature-based attention as an underlying mechanism.

    Science.gov (United States)

    Sneve, Markus H; Sreenivasan, Kartik K; Alnæs, Dag; Endestad, Tor; Magnussen, Svein

    2015-01-01

    Retention of features in visual short-term memory (VSTM) involves maintenance of sensory traces in early visual cortex. However, the mechanism through which this is accomplished is not known. Here, we formulate specific hypotheses derived from studies on feature-based attention to test the prediction that visual cortex is recruited by attentional mechanisms during VSTM of low-level features. Functional magnetic resonance imaging (fMRI) of human visual areas revealed that neural populations coding for task-irrelevant feature information are suppressed during maintenance of detailed spatial frequency memory representations. The narrow spectral extent of this suppression agrees well with known effects of feature-based attention. Additionally, analyses of effective connectivity during maintenance between retinotopic areas in visual cortex show that the observed highlighting of task-relevant parts of the feature spectrum originates in V4, a visual area strongly connected with higher-level control regions and known to convey top-down influence to earlier visual areas during attentional tasks. In line with this property of V4 during attentional operations, we demonstrate that modulations of earlier visual areas during memory maintenance have behavioral consequences, and that these modulations are a result of influences from V4. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The Effects of Short-Term Propofol and Dexmedetomidine on Lung Mechanics, Histology, and Biological Markers in Experimental Obesity.

    Science.gov (United States)

    Heil, Luciana Boavista Barros; Santos, Cíntia L; Santos, Raquel S; Samary, Cynthia S; Cavalcanti, Vinicius C M; Araújo, Mariana M P N; Poggio, Hananda; Maia, Lígia de A; Trevenzoli, Isis Hara; Pelosi, Paolo; Fernandes, Fatima C; Villela, Nivaldo R; Silva, Pedro L; Rocco, Patricia R M

    2016-04-01

    Administering anesthetics to the obese population requires caution because of a variety of reasons including possible interactions with the inflammatory process observed in obese patients. Propofol and dexmedetomidine have protective effects on pulmonary function and are widely used in short- and long-term sedation, particularly in intensive care unit settings in lean and obese subjects. However, the functional and biological effects of these drugs in obesity require further elucidation. In a model of diet-induced obesity, we compared the short-term effects of dexmedetomidine versus propofol on lung mechanics and histology, as well as biological markers of inflammation and oxidative stress modulation in obesity. Wistar rats (n = 56) were randomly fed a standard diet (lean) or experimental diet (obese) for 12 weeks. After this period, obese animals received sodium thiopental intraperitoneally and were randomly allocated into 4 subgroups: (1) nonventilated (n = 4) for molecular biology analysis only (control); (2) sodium thiopental (n = 8); (3) propofol (n = 8); and (4) dexmedetomidine (n = 8), which received continuous IV administration of the corresponding agents and were mechanically ventilated (tidal volume = 6 mL/kg body weight, fraction of inspired oxygen = 0.4, positive end-expiratory pressure = 3 cm H2O) for 1 hour. Compared with lean animals, obese rats did not present increased body weight but had higher total body and trunk fat percentages, airway resistance, and interleukin-6 levels in the lung tissue (P = 0.02, P = 0.0027, and P = 0.01, respectively). In obese rats, propofol, but not dexmedetomidine, yielded increased airway resistance, bronchoconstriction index (P = 0.016, P = 0.02, respectively), tumor necrosis factor-α, and interleukin-6 levels, as well as lower levels of nuclear factor-erythroid 2-related factor-2 and glutathione peroxidase (P = 0.001, Bonferroni-corrected t test). In this model of diet-induced obesity, a 1-hour propofol infusion

  18. Short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish (Danio rerio).

    Science.gov (United States)

    Cao, Fangjie; Wu, Peizhuo; Huang, Lan; Li, Hui; Qian, Le; Pang, Sen; Qiu, Lihong

    2018-05-01

    Previous study indicated that azoxystrobin had high acute toxicity to zebrafish, and larval zebrafish were more sensitive to azoxystrobin than adult zebrafish. The objective of the present study was to investigate short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish. After zebrafish embryos and adults were exposed to 0.01, 0.05 and 0.20 mg/L azoxystrobin (equal to 25, 124 and 496 nM azoxystrobin, respectively) for 8 days, the lethal effect, physiological responses, liver histology, mitochondrial ultrastructure, and expression alteration of genes related to mitochondrial respiration, oxidative stress, cell apoptosis and innate immune response were determined. The results showed that there was no significant effect on larval and adult zebrafish after exposure to 0.01 mg/L azoxystrobin. However, increased ROS, MDA concentration and il1b in larval zebrafish, as well as increased il1b, il8 and cxcl-c1c in adult zebrafish were induced after exposure to 0.05 mg/L azoxystrobin. Reduced mitochondrial complex III activity and ATP concentration, increased SOD activity, ROS and MDA concentration, decreased cytb, as well as increased sod1, sod2, cat, il1b, il8 and cxcl-c1c were observed both in larval and adult zebrafish after exposure to 0.20 mg/L azoxystrobin; meanwhile, increased p53, bax, apaf1 and casp9, alteration of liver histology and mitochondrial ultrastructure in larval zebrafish, and alteration of mitochondrial ultrastructure in adult zebrafish were also induced. The results demonstrated that azoxytrobin induced short-term developmental effects on larval zebrafish and adult zebrafish, including mitochondrial dysfunction, oxidative stress, cell apoptosis and innate immune response. Statistical analysis indicated that azoxystrobin induced more negative effects on larval zebrafish, which might be the reason for the differences of developmental toxicity between larval and adult zebrafish caused by

  19. Correlated individual differences suggest a common mechanism underlying metacognition in visual perception and visual short-term memory.

    Science.gov (United States)

    Samaha, Jason; Postle, Bradley R

    2017-11-29

    Adaptive behaviour depends on the ability to introspect accurately about one's own performance. Whether this metacognitive ability is supported by the same mechanisms across different tasks is unclear. We investigated the relationship between metacognition of visual perception and metacognition of visual short-term memory (VSTM). Experiments 1 and 2 required subjects to estimate the perceived or remembered orientation of a grating stimulus and rate their confidence. We observed strong positive correlations between individual differences in metacognitive accuracy between the two tasks. This relationship was not accounted for by individual differences in task performance or average confidence, and was present across two different metrics of metacognition and in both experiments. A model-based analysis of data from a third experiment showed that a cross-domain correlation only emerged when both tasks shared the same task-relevant stimulus feature. That is, metacognition for perception and VSTM were correlated when both tasks required orientation judgements, but not when the perceptual task was switched to require contrast judgements. In contrast with previous results comparing perception and long-term memory, which have largely provided evidence for domain-specific metacognitive processes, the current findings suggest that metacognition of visual perception and VSTM is supported by a domain-general metacognitive architecture, but only when both domains share the same task-relevant stimulus feature. © 2017 The Author(s).

  20. Short-term vegetation response following mechanical control of saltcedar (Tamarix spp.) on the Virgin River, Nevada, USA

    Science.gov (United States)

    Ostoja, Steven M.; Brooks, Matthew L.; Dudley, Tom; Lee, Steven R.

    2014-01-01

    Tamarisk (a.k.a. saltcedar, Tamarix spp.) is an invasive plant species that occurs throughout western riparian and wetland ecosystems. It is implicated in alterations of ecosystem structure and function and is the subject of many local control projects, including removal using heavy equipment. We evaluated short-term vegetation responses to mechanical Tamarix spp. removal at sites ranging from 2 to 5 yr post-treatment along the Virgin River in Nevada, USA. Treatments resulted in lower density and cover (but not eradication) of Tamarix spp., increased cover of the native shrub Pluchea sericia (arrow weed), decreased density and cover of all woody species combined, increased density of both native annual forbs and the nonnative annual Salsola tragus (prickly Russian-thistle), and lower density of nonnative annual grasses. The treated plots had lower mean woody species richness, but greater herbaceous species richness and diversity. Among herbaceous species, native taxa increased in richness whereas nonnative species increased in both species richness and diversity. Thus, efforts to remove Tamarix,/i> spp. at the Virgin River reduced vegetative cover contributing to fuel loads and probability of fire, and resulted in positive effects for native plant diversity, with mixed effects on other nonnative species. However, absolute abundances of native species

  1. The short-term stress response - Mother nature's mechanism for enhancing protection and performance under conditions of threat, challenge, and opportunity.

    Science.gov (United States)

    Dhabhar, Firdaus S

    2018-03-26

    Our group has proposed that in contrast to chronic stress that can have harmful effects, the short-term (fight-or-flight) stress response (lasting for minutes to hours) is nature's fundamental survival mechanism that enhances protection and performance under conditions involving threat/challenge/opportunity. Short-term stress enhances innate/primary, adaptive/secondary, vaccine-induced, and anti-tumor immune responses, and post-surgical recovery. Mechanisms and mediators include stress hormones, dendritic cell, neutrophil, macrophage, and lymphocyte trafficking/function and local/systemic chemokine and cytokine production. Short-term stress may also enhance mental/cognitive and physical performance through effects on brain, musculo-skeletal, and cardiovascular function, reappraisal of threat/anxiety, and training-induced stress-optimization. Therefore, short-term stress psychology/physiology could be harnessed to enhance immuno-protection, as well as mental and physical performance. This review aims to provide a conceptual framework and targets for further investigation of mechanisms and conditions under which the protective/adaptive aspects of short-term stress/exercise can be optimized/harnessed, and for developing pharmacological/biobehavioral interventions to enhance health/healing, and mental/cognitive/physical performance. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Short-term social memory deficits in adult female mice exposed to tannery effluent and possible mechanism of action.

    Science.gov (United States)

    Estrela, Fernanda Neves; Rabelo, Letícia Martins; Vaz, Boniek Gontijo; de Oliveira Costa, Denys Ribeiro; Pereira, Igor; de Lima Rodrigues, Aline Sueli; Malafaia, Guilherme

    2017-10-01

    The accumulated organic residues in tannery-plant courtyards are an eating attraction to small rodents; however, the contact of these animals with these residues may change their social behavior. Thus, the aim of the present study is to investigate whether the exposure to tannery effluent (TE) can damage the social recognition memory of female Swiss mice, as well as to assess whether vitamin C supplementation could provide information about how TE constituents can damage these animals' memory. We have observed that resident females exposed to TE (without vitamin supplementation) did not explore the anogenital region, their body or chased intruding females for shorter time or with lower frequency during the retest session of the social recognition test, fact that indicates social recognition memory deficit in these animals. Such finding is reinforced by the confirmation that there was no change in the animals' olfactory function during the buried food test, or locomotor changes in females exposed to the pollutant. Since no behavioral change was observed in the females exposed to TE and treated with vitamin C (before or after the exposure), it is possible saying that these social cognitive impairments seem to be directly related to the imbalance between the cellular production of reactive oxygen species and the counteracting antioxidant mechanisms (oxidative stress) in female mice exposed to the pollutant (without vitamin supplementation). Therefore, the present study evidences that the direct contact with tannery effluent, even for a short period-of-time, may cause short-term social memory deficits in adult female Swiss mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Comparative proteomic analysis of soybean leaves and roots by iTRAQ provides insights into response mechanisms to short-term salt stress

    Directory of Open Access Journals (Sweden)

    Wei eJi

    2016-04-01

    Full Text Available Salinity severely threatens land use capability and crop yields worldwide. Understanding the mechanisms that protect soybean from salt stress will help in the development of salt-stress tolerant leguminous plants. Here we firstly analyzed the changes in malondialdehyde levels, the activities of superoxide dismutase and peroxidases, cholorophyll contents, and Na+/K+ ratios in leaves and roots from soybean seedlings treated with 200 mM NaCl for different time points, and suggested that 200 mM NaCl treated for 12 h was enough for exploring proteomic analysis to soybean seedlings. iTRAQ-based proteomic approach was used to investigate the proteomes of soybean leaves and roots under salt treatment. Data are available via ProteomeXchange with identifier PXD002851. In total, 278 and 440 proteins with significantly altered abundance were identified in leaves and roots of soybean, respectively, with only 50 mutual unique proteins in the both tissues. These identified differentially expressed proteins (DEPs were mainly involved in 13 biological processes. Moreover, protein-protein interaction analysis revealed that the proteins involved in metabolism, carbohydrate and energy metabolism, protein synthesis and redox homeostasis constructed four types of response networks to high salt stress. Besides, semi-quantitative RT-PCR analysis revealed that some of the proteins, such as 14-3-3, MMK2, PP1, TRX-h, were also regulated by salt stress at the level of transcription. These results indicated that effective regulatory protein expression related to signalling, membrane and transport, stress defense and metabolism played important roles in the short-term salt response of soybean seedlings.

  4. Brief communication: sliding displacement of amnion and chorion following controlled laser wounding suggests a mechanism for short-term sealing of ruptured membranes.

    Science.gov (United States)

    Behzad, F; Dickinson, M R; Charlton, A; Aplin, J D

    1994-10-01

    The Erbium-YAG laser was used to produce narrow wounds of defined depth in term amniochorion. The charring effect of the laser meant that sites could be readily localized in histological sections. During brief post-wounding incubations, sliding displacement of the amnion relative to the chorion occurred through the plane of the spongy layer. This suggests a possible short-term mechanism whereby a spontaneous rupture could be sealed in vivo.

  5. Predictable 'meta-mechanisms' emerge from feedbacks between transpiration and plant growth and cannot be simply deduced from short-term mechanisms.

    Science.gov (United States)

    Tardieu, François; Parent, Boris

    2017-06-01

    Growth under water deficit is controlled by short-term mechanisms but, because of numerous feedbacks, the combination of these mechanisms over time often results in outputs that cannot be deduced from the simple inspection of individual mechanisms. It can be analysed with dynamic models in which causal relationships between variables are considered at each time-step, allowing calculation of outputs that are routed back to inputs for the next time-step and that can change the system itself. We first review physiological mechanisms involved in seven feedbacks of transpiration on plant growth, involving changes in tissue hydraulic conductance, stomatal conductance, plant architecture and underlying factors such as hormones or aquaporins. The combination of these mechanisms over time can result in non-straightforward conclusions as shown by examples of simulation outputs: 'over production of abscisic acid (ABA) can cause a lower concentration of ABA in the xylem sap ', 'decreasing root hydraulic conductance when evaporative demand is maximum can improve plant performance' and 'rapid root growth can decrease yield'. Systems of equations simulating feedbacks over numerous time-steps result in logical and reproducible emergent properties that can be viewed as 'meta-mechanisms' at plant level, which have similar roles as mechanisms at cell level. © 2016 John Wiley & Sons Ltd.

  6. Predictors of survival and ability to wean from short-term mechanical circulatory support device following acute myocardial infarction complicated by cardiogenic shock.

    Science.gov (United States)

    Garan, A Reshad; Eckhardt, Christina; Takeda, Koji; Topkara, Veli K; Clerkin, Kevin; Fried, Justin; Masoumi, Amirali; Demmer, Ryan T; Trinh, Pauline; Yuzefpolskaya, Melana; Naka, Yoshifumi; Burkhoff, Dan; Kirtane, Ajay; Colombo, Paolo C; Takayama, Hiroo

    2017-11-01

    Cardiogenic shock following acute myocardial infarction (AMI-CS) portends a poor prognosis. Short-term mechanical circulatory support devices (MCSDs) provide hemodynamic support for patients with cardiogenic shock but predictors of survival and the ability to wean from short-term MCSDs remain largely unknown. All patients > 18 years old treated at our institution with extra-corporeal membrane oxygenation or short-term surgical ventricular assist device for AMI-CS were studied. We collected acute myocardial infarction details with demographic and hemodynamic variables. Primary outcomes were survival to discharge and recovery from MCSD (i.e. survival without heart replacement therapy including durable ventricular assist device or heart transplant). One hundred and twenty-four patients received extra-corporeal membrane oxygenation or short-term surgical ventricular assist device following acute myocardial infarction from 2007 to 2016; 89 received extra-corporeal membrane oxygenation and 35 short-term ventricular assist device. Fifty-five (44.4%) died in the hospital and 69 (55.6%) survived to discharge. Twenty-six (37.7%) required heart replacement therapy (four transplant, 22 durable ventricular assist device) and 43 (62.3%) were discharged without heart replacement therapy. Age and cardiac index at MCSD implantation were predictors of survival to discharge; patients over 60 years with cardiac index <1.5 l/min per m 2 had a low likelihood of survival. The angiographic result after revascularization predicted recovery from MCSD (odds ratio 9.00, 95% confidence interval 2.45-32.99, p=0.001), but 50% of those optimally revascularized still required heart replacement therapy. Cardiac index predicted recovery from MCSD among this group (odds ratio 4.06, 95% confidence interval 1.45-11.55, p=0.009). Among AMI-CS patients requiring short-term MCSDs, age and cardiac index predict survival to discharge. Angiographic result and cardiac index predict ventricular recovery but 50

  7. Short-term mechanical circulatory support as a bridge to durable left ventricular assist device implantation in refractory cardiogenic shock: a systematic review and meta-analysis.

    Science.gov (United States)

    den Uil, Corstiaan A; Akin, Sakir; Jewbali, Lucia S; Dos Reis Miranda, Dinis; Brugts, Jasper J; Constantinescu, Alina A; Kappetein, Arie Pieter; Caliskan, Kadir

    2017-07-01

    Short-term mechanical circulatory support (MCS) is increasingly used as a bridge to decision in patients with refractory cardiogenic shock. Subsequently, these patients might be bridged to durable MCS either as a bridge to candidacy/transplantation, or as destination therapy. The aim of this study was to review support duration and clinical outcome of short-term MCS in cardiogenic shock, and to analyse application of this technology as a bridge to long-term cardiac support (left ventricular assist device, LVAD) from 2006 till June 2016. Using Cochrane Register of Trials, Embase and Medline, a systematic review was performed on patients with cardiogenic shock from acute myocardial infarction, end-stage cardiomyopathy, or acute myocarditis, receiving short-term MCS. Studies on periprocedural, post-cardiotomy and cardiopulmonary resuscitation support were excluded. Thirty-nine studies, mainly registries of heterogeneous patient populations (n = 4151 patients), were identified. Depending on the device used (intra-aortic balloon pump, TandemHeart, Impella 2.5, Impella 5.0, CentriMag and peripheral veno-arterial extracorporeal membrane oxygenation), mean support duration was (range) 1.6-25 days and the mean proportion of short-term MCS patients discharged was (range) 45-66%. The mean proportion of bridge to durable LVAD was (range) 3-30%. Bridge to durable LVAD was most frequently performed in patients with end-stage cardiomyopathy (22 [12-35]%). We conclude that temporary MCS can be used to bridge patients with cardiogenic shock towards durable LVAD. Clinicians are encouraged to share their results in a large multicentre registry in order to investigate optimal device selection and best duration of support. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  8. Short-term memory

    Science.gov (United States)

    Toulouse, G.

    This is a rather bold attempt to bridge the gap between neuron structure and psychological data. We try to answer the question: Is there a relation between the neuronal connectivity in the human cortex (around 5,000) and the short-term memory capacity (7±2)? Our starting point is the Hopfield model (Hopfield 1982), presented in this volume by D.J. Amit.

  9. The Demonstration of Short-Term Consolidation.

    Science.gov (United States)

    Jolicoeur, Pierre; Dell'Acqua, Roberto

    1998-01-01

    Results of seven experiments involving 112 college students or staff using a dual-task approach provide evidence that encoding information into short-term memory involves a distinct process termed short-term consolidation (STC). Results suggest that STC has limited capacity and that it requires central processing mechanisms. (SLD)

  10. Ethical dilemma: offering short-term extracorporeal membrane oxygenation support for terminally ill children who are not candidates for long-term mechanical circulatory support or heart transplantation.

    Science.gov (United States)

    Shankar, Venkat; Costello, John P; Peer, Syed M; Klugman, Darren; Nath, Dilip S

    2014-04-01

    The use of extracorporeal membrane oxygenation (ECMO) in terminally ill pediatric patients who are not candidates for long-term mechanical circulatory support or heart transplantation requires careful deliberation. We present the case of a 16-year-old female with a relapse of acute lymphoid leukemia and acute-on-chronic cardiomyopathy who received short-term ECMO therapy. In addition, we highlight several ethical considerations that were crucial to this patient's family-centered care and demonstrate that this therapy can be accomplished in a manner that respects patient autonomy and family wishes.

  11. Effect of Short-Term Water Exposure on the Mechanical Properties of Halloysite Nanotube-Multi Layer Graphene Reinforced Polyester Nanocomposites

    Directory of Open Access Journals (Sweden)

    Mohd Shahneel Saharudin

    2017-01-01

    Full Text Available The influence of short-term water absorption on the mechanical properties of halloysite nanotubes-multi layer graphene reinforced polyester hybrid nanocomposites has been investigated. The addition of nano-fillers significantly increased the flexural strength, tensile strength, and impact strength in dry and wet conditions. After short-term water exposure, the maximum microhardness, tensile, flexural and impact toughness values were observed at 0.1 wt % multi-layer graphene (MLG. The microhardness increased up to 50.3%, tensile strength increased up to 40% and flexural strength increased up to 44%. Compared to dry samples, the fracture toughness and surface roughness of all types of produced nanocomposites were increased that may be attributed to the plasticization effect. Scanning electron microscopy revealed that the main failure mechanism is caused by the weakening of the nano-filler-matrix interface induced by water absorption. It was further observed that synergistic effects were not effective at a concentration of 0.1 wt % to produce considerable improvement in the mechanical properties of the produced hybrid nanocomposites.

  12. Modelling of long-term and short-term mechanisms of arterial pressure control in the cardiovascular system: an object-oriented approach.

    Science.gov (United States)

    Fernandez de Canete, J; Luque, J; Barbancho, J; Munoz, V

    2014-04-01

    A mathematical model that provides an overall description of both the short- and long-term mechanisms of arterial pressure regulation is presented. Short-term control is exerted through the baroreceptor reflex while renal elimination plays a role in long-term control. Both mechanisms operate in an integrated way over the compartmental model of the cardiovascular system. The whole system was modelled in MODELICA, which uses a hierarchical object-oriented modelling strategy, under the DYMOLA simulation environment. The performance of the controlled system was analysed by simulation in light of the existing hypothesis and validation tests previously performed with physiological data, demonstrating the effectiveness of both regulation mechanisms under physiological and pathological conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Market data analysis and short-term price forecasting in the Iran electricity market with pay-as-bid payment mechanism

    International Nuclear Information System (INIS)

    Bigdeli, N.; Afshar, K.; Amjady, N.

    2009-01-01

    Market data analysis and short-term price forecasting in Iran electricity market as a market with pay-as-bid payment mechanism has been considered in this paper. The data analysis procedure includes both correlation and predictability analysis of the most important load and price indices. The employed data are the experimental time series from Iran electricity market in its real size and is long enough to make it possible to take properties such as non-stationarity of market into account. For predictability analysis, the bifurcation diagrams and recurrence plots of the data have been investigated. The results of these analyses indicate existence of deterministic chaos in addition to non-stationarity property of the system which implies short-term predictability. In the next step, two artificial neural networks have been developed for forecasting the two price indices in Iran's electricity market. The models' input sets are selected regarding four aspects: the correlation properties of the available data, the critiques of Iran's electricity market, a proper convergence rate in case of sudden variations in the market price behavior, and the omission of cumulative forecasting errors. The simulation results based on experimental data from Iran electricity market are representative of good performance of the developed neural networks in coping with and forecasting of the market behavior, even in the case of severe volatility in the market price indices. (author)

  14. Do Subjects with Whiplash-Associated Disorders Respond Differently in the Short-Term to Manual Therapy and Exercise than Those with Mechanical Neck Pain?

    Science.gov (United States)

    Castaldo, Matteo; Catena, Antonella; Chiarotto, Alessandro; Fernández-de-Las-Peñas, César; Arendt-Nielsen, Lars

    2017-04-01

    To compare the short-term effects of manual therapy and exercise on pain, related disability, range of motion, and pressure pain thresholds between subjects with mechanical neck pain and whiplash-associated disorders. Twenty-two subjects with mechanical neck pain and 28 with whiplash-associated disorders participated. Clinical and physical outcomes including neck pain intensity, neck-related disability, and pain area, as well as cervical range of motion and pressure pain thresholds over the upper trapezius and tibialis anterior muscles, were obtained at baseline and after the intervention by a blinded assessor. Each subject received six sessions of manual therapy and specific neck exercises. Mixed-model repeated measures analyses of covariance (ANCOVAs) were used for the analyses. Subjects with whiplash-associated disorders exhibited higher neck-related disability ( P  = 0.021), larger pain area ( P  = 0.003), and lower pressure pain thresholds in the tibialis anterior muscle ( P  = 0.009) than those with mechanical neck pain. The adjusted ANCOVA revealed no between-group differences for any outcome (all P  > 0.15). A significant main effect of time was demonstrated for clinical outcomes and cervical range of motion with both groups experiencing similar improvements (all P   0.222). The current clinical trial found that subjects with mechanical neck pain and whiplash-associated disorders exhibited similar clinical and neurophysiological responses after a multimodal physical therapy intervention, suggesting that although greater signs of central sensitization are present in subjects with whiplash-associated disorders, this does not alter the response in the short term to manual therapy and exercises. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  15. Short-term adaptations in spinal cord circuits evoked by repetitive transcranial magnetic stimulation: possible underlying mechanisms

    DEFF Research Database (Denmark)

    Perez, Monica A.; Lungholt, Bjarke K.S.; Nielsen, Jens Bo

    2005-01-01

    Repetitive transcranial magnetic stimulation (rTMS) has been shown to induce adaptations in cortical neuronal circuitries. In the present study we investigated whether rTMS, through its effect on corticospinal pathways, also produces adaptations at the spinal level, and what the neuronal mechanisms...... that the depression of the H-reflex by rTMS can be explained, at least partly, by an increased presynaptic inhibition of soleus Ia afferents. In contrast, rTMS had no effect on disynaptic reciprocal Ia inhibition from ankle dorsiflexors to plantarflexors. We conclude that a train of rTMS may modulate transmission...

  16. Mechanisms of Short-Term Training-Induced Reaching Improvement in Severely Hemiparetic Stroke Patients: A TMS Study

    Science.gov (United States)

    Harris-Love, Michelle L.; Morton, Susanne M.; Perez, Monica A.; Cohen, Leonardo G.

    2011-01-01

    Background The neurophysiological mechanisms underlying improved upper-extremity motor skills have been partially investigated in patients with good motor recovery but are poorly understood in more impaired individuals, the majority of stroke survivors. Objective The authors studied changes in primary motor cortex (M1) excitability (motor evoked potentials [MEPs], contralateral and ipsilateral silent periods [CSPs and ISPs] using transcranial magnetic stimulation [TMS]) associated with training-induced reaching improvement in stroke patients with severe arm paresis (n = 11; Upper-Extremity Fugl-Meyer score (F-M) = 27 ± 6). Methods All patients underwent a single session of reaching training focused on moving the affected hand from a resting site to a target placed at 80% of maximum forward reaching amplitude in response to a visual “GO” cue. Triceps contribute primarily as agonist and biceps primarily as antagonist to the trained forward reaching movement. Response times were recorded for each reaching movement. Results Preceding training (baseline), greater interhemispheric inhibition (measured by ISP) in the affected triceps muscle, reflecting inhibition from the nonlesioned to the lesioned M1, was observed in patients with lower F-M scores (more severe motor impairment). Training-induced improvements in reaching were greater in patients with slower response times at baseline. Increased MEP amplitudes and decreased ISPs and CSPs were observed in the affected triceps but not in the biceps muscle after training. Conclusion These results indicate that along with training-induced motor improvements, training-specific modulation of intrahemispheric and interhemispheric mechanisms occurs after reaching practice in chronic stroke patients with substantial arm impairment. PMID:21343522

  17. Short-Term Prognosis of Mechanically Ventilated Patients With Guillain-Barré Syndrome Is Worsened by Corticosteroids as an Add-On Therapy.

    Science.gov (United States)

    Wu, Xiujuan; Zhang, Bing; Li, Chunrong; Shen, Donghui; Liu, Kangding; Zhu, Jie; Zhang, Hong-Liang

    2015-10-01

    Intravenous immunoglobulin (IVIg) has been proven most effective in treating Guillain-Barré syndrome (GBS). Corticosteroids as an add-on therapy have been prescribed in severe GBS cases. However, the efficacy of intravenous corticosteroids combined with IVIg in dealing with severe GBS remains unclear. We explored the therapeutic effects of different therapeutic regimens on the short-term prognosis of GBS patients, especially the severe cases.We retrospectively analyzed the clinical data of 527 adult patients with GBS who were prescribed to different treatments from 2003 to 2014. The therapeutic effect of a treatment was evaluated by the improvement of Hughes Functional Grading Scale (HFGS) and Medical Research Council (MRC) sum score.With comparable incidence of infectious complications (P > 0.05), more mechanically ventilated patients were found improvement after IVIg treatment than combination IVIg with intravenous corticosteroids (MRC: 97% vs. 72.4%, P bedridden patients without mechanical ventilation, incidence of infectious complications (P > 0.05) and ratio of patients who were improved after IVIg were insignificantly different from the combination therapy (MRC: 89.6% vs. 86.5%; HFGS: 69.6% vs. 61.5%; both P > 0.05), even if the intravenous corticosteroids were initiated within 7 days after onset (P > 0.05). In addition, supportive treatment was sufficient for patients who were able to walk with help (HFGS = 3) and mildly affected (HFGS  3), while corticosteroids are detrimental for short-term prognosis in mechanically ventilated patients when used in combination with IVIg. Further prospective and randomized studies are warranted to validate this finding.

  18. Short-Term Prognosis of Mechanically Ventilated Patients With Guillain–Barré Syndrome Is Worsened by Corticosteroids as an Add-On Therapy

    Science.gov (United States)

    Wu, Xiujuan; Zhang, Bing; Li, Chunrong; Shen, Donghui; Liu, Kangding; Zhu, Jie; Zhang, Hong-Liang

    2015-01-01

    Abstract Intravenous immunoglobulin (IVIg) has been proven most effective in treating Guillain–Barré syndrome (GBS). Corticosteroids as an add-on therapy have been prescribed in severe GBS cases. However, the efficacy of intravenous corticosteroids combined with IVIg in dealing with severe GBS remains unclear. We explored the therapeutic effects of different therapeutic regimens on the short-term prognosis of GBS patients, especially the severe cases. We retrospectively analyzed the clinical data of 527 adult patients with GBS who were prescribed to different treatments from 2003 to 2014. The therapeutic effect of a treatment was evaluated by the improvement of Hughes Functional Grading Scale (HFGS) and Medical Research Council (MRC) sum score. With comparable incidence of infectious complications (P > 0.05), more mechanically ventilated patients were found improvement after IVIg treatment than combination IVIg with intravenous corticosteroids (MRC: 97% vs. 72.4%, P bedridden patients without mechanical ventilation, incidence of infectious complications (P > 0.05) and ratio of patients who were improved after IVIg were insignificantly different from the combination therapy (MRC: 89.6% vs. 86.5%; HFGS: 69.6% vs. 61.5%; both P > 0.05), even if the intravenous corticosteroids were initiated within 7 days after onset (P > 0.05). In addition, supportive treatment was sufficient for patients who were able to walk with help (HFGS = 3) and mildly affected (HFGS  3), while corticosteroids are detrimental for short-term prognosis in mechanically ventilated patients when used in combination with IVIg. Further prospective and randomized studies are warranted to validate this finding. PMID:26512609

  19. Lithosphere-atmosphere-ionosphere coupling as governing mechanism for preseismic short-term events in atmosphere and ionosphere

    Directory of Open Access Journals (Sweden)

    O. Molchanov

    2004-01-01

    Full Text Available We present a general concept of mechanisms of preseismic phenomena in the atmosphere and ionosphere. After short review of observational results we conclude: 1. Upward migration of fluid substrate matter (bubble can lead to ousting of the hot water/gas near the ground surface and cause an earthquake (EQ itself in the strength-weakened area; 2. Thus, time and place of the bubble appearance could be random values, but EQ, geochemistry anomaly and foreshocks (seismic, SA and ULF electromagnetic ones are casually connected; 3. Atmospheric perturbation of temperature and density could follow preseismic hot water/gas release resulting in generation of atmospheric gravity waves (AGW with periods in a range of 6–60min; 4. Seismo-induced AGW could lead to modification of the ionospheric turbulence and to the change of over-horizon radio-wave propagation in the atmosphere, perturbation of LF waves in the lower ionosphere and ULF emission depression at the ground.

  20. Effects of flooding on phosphorus and iron mobilization in highly weathered soils: Short-term effects and mechanisms

    Science.gov (United States)

    Maranguit, Deejay

    2017-04-01

    limited by the amount of available carbon (C) as an energy source for microorganisms. Moreover, microbial mineralization of organic P from SOM also increases P availability, and this process requires available C. This interpretation was supported by the strong correlation (R2 = 0.58) between available P and DOC, as well as between DP and DOC (R2 = 0.56) in topsoil. The increasing soil solution pH in topsoil and subsoil after flooding of all land-use types may also influence the P release over time. In summary, the increase of available P and DP during flooding is due to three main mechanisms: (1) P release via the microbially-mediated reductive dissolution of Fe3+ oxides; (2) P release during SOM mineralization and (3) solubility of Fe phosphate due to increasing pH. These mechanisms are relevant not only in riparian areas, where flooding occurs, but also in well-drained soil that is partly waterlogged after regular heavy rainfalls during the wet season. Likewise, the P cycle turnover is faster in compacted, often anaerobic plantation soils. Here, more P is pumped by the vegetation and then removed from plantations due to yield export.

  1. Short-term combined effects of thoracic spine thrust manipulation and cervical spine nonthrust manipulation in individuals with mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Masaracchio, Michael; Cleland, Joshua A; Hellman, Madeleine; Hagins, Marshall

    2013-03-01

    Randomized clinical trial. To investigate the short-term effects of thoracic spine thrust manipulation combined with cervical spine nonthrust manipulation (experimental group) versus cervical spine nonthrust manipulation alone (comparison group) in individuals with mechanical neck pain. Research has demonstrated improved outcomes with both nonthrust manipulation directed at the cervical spine and thrust manipulation directed at the thoracic spine in patients with neck pain. Previous studies have not determined if thoracic spine thrust manipulation may increase benefits beyond those provided by cervical nonthrust manipulation alone. Sixty-four participants with mechanical neck pain were randomized into 1 of 2 groups, an experimental or comparison group. Both groups received 2 treatment sessions of cervical spine nonthrust manipulation and a home exercise program consisting of active range-of-motion exercises, and the experimental group received additional thoracic spine thrust manipulations. Outcome measures were collected at baseline and at a 1-week follow-up, and included the numeric pain rating scale, the Neck Disability Index, and the global rating of change. Participants in the experimental group demonstrated significantly greater improvements (Ppain rating scale and Neck Disability Index at the 1-week follow-up compared to those in the comparison group. In addition, 31 of 33 (94%) participants in the experimental group, compared to 11 of 31 participants (35%) in the comparison group, indicated a global rating of change score of +4 or higher at the 1-week follow-up, with an associated number needed to treat of 2. Individuals with neck pain who received a combination of thoracic spine thrust manipulation and cervical spine nonthrust manipulation plus exercise demonstrated better overall short-term outcomes on the numeric pain rating scale, the Neck Disability Index, and the global rating of change.

  2. Fast Weight Long Short-Term Memory

    OpenAIRE

    Keller, T. Anderson; Sridhar, Sharath Nittur; Wang, Xin

    2018-01-01

    Associative memory using fast weights is a short-term memory mechanism that substantially improves the memory capacity and time scale of recurrent neural networks (RNNs). As recent studies introduced fast weights only to regular RNNs, it is unknown whether fast weight memory is beneficial to gated RNNs. In this work, we report a significant synergy between long short-term memory (LSTM) networks and fast weight associative memories. We show that this combination, in learning associative retrie...

  3. Molecular mechanism of the short-term cardiotoxicity caused by 2',3'-dideoxycytidine (ddC): modulation of reactive oxygen species levels and ADP-ribosylation reactions.

    Science.gov (United States)

    Skuta, G; Fischer, G M; Janaky, T; Kele, Z; Szabo, P; Tozser, J; Sumegi, B

    1999-12-15

    The short-term cardiac side effects of 2',3'-dideoxycytidine (ddC, zalcitabine) were studied in rats in order to understand the biochemical events contributing to the development of ddC-induced cardiomyopathy. In developing animals, ddC treatment provoked a surprisingly rapid appearance of cardiac malfunctions characterized by prolonged RR, PR, and QT intervals and J point depression. The energy metabolism in the heart was compromised, characterized by a decreased creatine phosphate/creatine ratio (from 2.05 normal value to 0.75) and a decreased free ATP/ADP ratio (from 332 normal value to 121). The activity of respiratory complexes (NADH: cytochrome c oxidoreductase and cytochrome oxidase) also decreased significantly. Southern blot and polymerase chain reaction analysis did not show deletions or a decrease in the quantity of mitochondrial DNA (mtDNA) deriving from ddC-treated rat hearts, indicating that under our experimental conditions, ddC-induced heart abnormalities were not the direct consequence of mtDNA-related damage. The ddC treatment of rats significantly increased the formation of reactive oxygen species (ROS) in heart and skeletal muscle as determined by the oxidation of non-fluorescent dihydrorhodamine123 to fluorescent rhodamine123 and the oxidation of cellular proteins determined from protein carbonyl content. An activation of the nuclear poly-(ADP-ribose) polymerase (EC 2.4.2.30) and an increase in the mono-ADP-ribosylation of glucose-regulated protein and desmin were observed in the cardiac tissue from ddC-treated animals. A decrease in the quantity of heat shock protein (HSP)70s was also detected, while the level of HSP25 and HSP60 remained unchanged. Surprisingly, ddC treatment induced a skeletal muscle-specific decrease in the quantity of three proteins, one of which was identified by N-terminal sequencing as myoglobin, and another by tandem mass spectrometer sequencing as triosephosphate isomerase (EC 5.3.1.1). These data show that the short

  4. High-Strength Ultra-Fine-Grained Hypereutectic Al-Si-Fe-X (X = Cr, Mn) Alloys Prepared by Short-Term Mechanical Alloying and Spark Plasma Sintering.

    Science.gov (United States)

    Průša, Filip; Bláhová, Markéta; Vojtěch, Dalibor; Kučera, Vojtěch; Bernatiková, Adriana; Kubatík, Tomáš František; Michalcová, Alena

    2016-11-30

    In this work, Al-20Si-10Fe-6Cr and Al-20Si-10Fe-6Mn (wt %) alloys were prepared by a combination of short-term mechanical alloying and spark plasma sintering. The microstructure was composed of homogeneously dispersed intermetallic particles forming composite-like structures. X-ray diffraction analysis and TEM + EDS analysis determined that the α-Al along with α-Al 15 (Fe,Cr)₃Si₂ or α-Al 15 (Fe,Mn)₃Si₂ phases were present, with dimensions below 130 nm. The highest hardness of 380 ± 7 HV5 was observed for the Al-20Si-10Fe-6Mn alloy, exceeding the hardness of the reference as-cast Al-12Si-1Cu-1 Mg-1Ni alloy (121 ± 2 HV5) by nearly a factor of three. Both of the prepared alloys showed exceptional thermal stability with the hardness remaining almost the same even after 100 h of annealing at 400 °C. Additionally, the compressive strengths of the Al-20Si-10Fe-6Cr and Al-20Si-10Fe-6Mn alloys reached 869 MPa and 887 MPa, respectively, and had virtually the same values of 870 MPa and 865 MPa, respectively, even after 100 h of annealing. More importantly, the alloys showed an increase in ductility at 400 °C, reaching several tens of percent. Thus, both of the investigated alloys showed better mechanical properties, including superior hardness, compressive strength and thermal stability, as compared to the reference Al-10Si-1Cu-1Mg-1Ni alloy, which softened remarkably, reducing its hardness by almost 50% to 63 ± 8 HV5.

  5. High-Strength Ultra-Fine-Grained Hypereutectic Al-Si-Fe-X (X = Cr, Mn) Alloys Prepared by Short-Term Mechanical Alloying and Spark Plasma Sintering

    Science.gov (United States)

    Průša, Filip; Bláhová, Markéta; Vojtěch, Dalibor; Kučera, Vojtěch; Bernatiková, Adriana; Kubatík, Tomáš František; Michalcová, Alena

    2016-01-01

    In this work, Al-20Si-10Fe-6Cr and Al-20Si-10Fe-6Mn (wt %) alloys were prepared by a combination of short-term mechanical alloying and spark plasma sintering. The microstructure was composed of homogeneously dispersed intermetallic particles forming composite-like structures. X-ray diffraction analysis and TEM + EDS analysis determined that the α-Al along with α-Al15(Fe,Cr)3Si2 or α-Al15(Fe,Mn)3Si2 phases were present, with dimensions below 130 nm. The highest hardness of 380 ± 7 HV5 was observed for the Al-20Si-10Fe-6Mn alloy, exceeding the hardness of the reference as-cast Al-12Si-1Cu-1 Mg-1Ni alloy (121 ± 2 HV5) by nearly a factor of three. Both of the prepared alloys showed exceptional thermal stability with the hardness remaining almost the same even after 100 h of annealing at 400 °C. Additionally, the compressive strengths of the Al-20Si-10Fe-6Cr and Al-20Si-10Fe-6Mn alloys reached 869 MPa and 887 MPa, respectively, and had virtually the same values of 870 MPa and 865 MPa, respectively, even after 100 h of annealing. More importantly, the alloys showed an increase in ductility at 400 °C, reaching several tens of percent. Thus, both of the investigated alloys showed better mechanical properties, including superior hardness, compressive strength and thermal stability, as compared to the reference Al-10Si-1Cu-1Mg-1Ni alloy, which softened remarkably, reducing its hardness by almost 50% to 63 ± 8 HV5. PMID:28774094

  6. Disruption of Short-Term Memory by Changing and Deviant Sounds: Support for a Duplex-Mechanism Account of Auditory Distraction

    Science.gov (United States)

    Hughes, Robert W.; Vachon, Francois; Jones, Dylan M.

    2007-01-01

    The disruption of short-term memory by to-be-ignored auditory sequences (the changing-state effect) has often been characterized as attentional capture by deviant events (deviation effect). However, the present study demonstrates that changing-state and deviation effects are functionally distinct forms of auditory distraction: The disruption of…

  7. Structure and mechanical properties of Al-Si-Fe alloys prepared by short-term mechanical alloying and Spark Plasma Sintering

    Czech Academy of Sciences Publication Activity Database

    Průša, J.; Vojtěch, D.; Bláhová, M.; Michalcová, A.; Kubatík, Tomáš František; Čížek, J.

    2015-01-01

    Roč. 75, June (2015), s. 65-75 ISSN 0261-3069 Institutional support: RVO:61389021 Keywords : Aluminium alloy s * Mechanical Properties * Microstructure * Mechanical alloy ing * Spark-Plasma Sintering Subject RIV: JG - Metallurgy Impact factor: 3.997, year: 2015 http://www.sciencedirect.com/science/article/pii/S0261306915000990#

  8. A Short Term Analogue Memory

    DEFF Research Database (Denmark)

    Shah, Peter Jivan

    1992-01-01

    A short term analogue memory is described. It is based on a well-known sample-hold topology in which leakage currents have been minimized partly by circuit design and partly by layout techniques. Measurements on a test chip implemented in a standard 2.4 micron analogue CMOS process show a droop...

  9. Short-term LNG-markets

    International Nuclear Information System (INIS)

    Eldegard, Tom; Lund, Arne-Christian; Miltersen, Kristian; Rud, Linda

    2005-01-01

    The global Liquefied Natural Gas (LNG) industry has experienced substantial growth in the past decades. In the traditional trade patterns of LNG the product has typically been handled within a dedicated chain of plants and vessels fully committed by long term contracts or common ownership, providing risk sharing of large investments in a non-liquid market. Increasing gas prices and substantial cost reductions in all parts of the LNG chain have made LNG projects viable even if only part of the capacity is secured by long-term contracts, opening for more flexible trade of the remainder. Increasing gas demand, especially in power generation, combined with cost reductions in the cost of LNG terminals, open new markets for LNG. For the LNG supplier, the flexibility of shifting volumes between regions represents an additional value. International trade in LNG has been increasing, now accounting for more than one fifth of the world's cross-border gas trade. Despite traditional vertical chain bonds, increased flexibility has contributed in fact to an increasing LNG spot trade, representing 8% of global trade in 2002. The focus of this paper is on the development of global short-term LNG markets, and their role with respect to efficiency and security of supply in European gas markets. Arbitrage opportunities arising from price differences between regional markets (such as North America versus Europe) are important impetuses for flexible short-term trade. However, the short-term LNG trade may suffer from problems related to market access, e.g. limited access to terminals and regulatory issues, as well as rigidities connected to vertical binding within the LNG chain. Important issues related to the role of short-term LNG-trade in the European gas market are: Competition, flexibility in meeting peak demand, security of supply and consequences of differences in pricing policies (oil-linked prices in Europe and spot market prices in North America). (Author)

  10. The Mind and Brain of Short-Term Memory

    OpenAIRE

    Jonides, John; Lewis, Richard L.; Nee, Derek Evan; Lustig, Cindy A.; Berman, Marc G.; Moore, Katherine Sledge

    2008-01-01

    The past 10 years have brought near-revolutionary changes in psychological theories about short-term memory, with similarly great advances in the neurosciences. Here, we critically examine the major psychological theories (the “mind”) of short-term memory and how they relate to evidence about underlying brain mechanisms. We focus on three features that must be addressed by any satisfactory theory of short-term memory. First, we examine the evidence for the architecture of short-term memory, w...

  11. Comparative short-term effects of two thoracic spinal manipulation techniques in subjects with chronic mechanical neck pain: a randomized controlled trial.

    Science.gov (United States)

    Casanova-Méndez, Amaloha; Oliva-Pascual-Vaca, Angel; Rodriguez-Blanco, Cleofás; Heredia-Rizo, Alberto Marcos; Gogorza-Arroitaonandia, Kristobal; Almazán-Campos, Ginés

    2014-08-01

    Spinal Manipulation (SM) has been purported to decrease pain and improve function in subjects with non-specific neck pain. Previous research has investigated which individuals with non-specific neck pain will be more likely to benefit from SM. It has not yet been proven whether or not the effectiveness of thoracic SM depends on the specific technique being used. This double-blind randomized trial has compared the short-term effects of two thoracic SM maneuvers in subjects with chronic non-specific neck pain. Sixty participants were distributed randomly into two groups. One group received the Dog technique (n = 30), with the subject in supine position, and the other group underwent the Toggle-Recoil technique (n = 30), with the participant lying prone, T4 being the targeted area in both cases. Evaluations were made of self-reported neck pain (Visual Analogue Scale); neck mobility (Cervical Range of Motion); and pressure pain threshold at the cervical and thoracic levels (C4 and T4 spinous process) and over the site described for location of tense bands of the upper trapezius muscle. Measurements were taken before intervention, immediately afterward, and 20 min later. Both maneuvers improved neck mobility and mechanosensitivity and reduced pain in the short term. No major or clinical differences were found between the groups. In the between-groups comparison slightly better results were observed in the Toggle-Recoil group only for cervical extension (p = 0.009), right lateral flexion (p = 0.004) and left rotation (p < 0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Mechanisms controlling primary and new production in a global ecosystem model – Part II: The role of the upper ocean short-term periodic and episodic mixing events

    Directory of Open Access Journals (Sweden)

    E. E. Popova

    2006-01-01

    Full Text Available The use of 6 h, daily, weekly and monthly atmospheric forcing resulted in dramatically different predictions of plankton productivity in a global 3-D coupled physical-biogeochemical model. Resolving the diurnal cycle of atmospheric variability by use of 6 h forcing, and hence also diurnal variability in UML depth, produced the largest difference, reducing predicted global primary and new production by 25% and 10% respectively relative to that predicted with daily and weekly forcing. This decrease varied regionally, being a 30% reduction in equatorial areas primarily because of increased light limitation resulting from deepening of the mixed layer overnight as well as enhanced storm activity, and 25% at moderate and high latitudes primarily due to increased grazing pressure resulting from late winter stratification events. Mini-blooms of phytoplankton and zooplankton occur in the model during these events, leading to zooplankton populations being sufficiently well developed to suppress the progress of phytoplankton blooms. A 10% increase in primary production was predicted in the peripheries of the oligotrophic gyres due to increased storm-induced nutrient supply end enhanced winter production during the short term stratification events that are resolved in the run forced by 6 h meteorological fields. By resolving the diurnal cycle, model performance was significantly improved with respect to several common problems: underestimated primary production in the oligotrophic gyres; overestimated primary production in the Southern Ocean; overestimated magnitude of the spring bloom in the subarctic Pacific Ocean, and overestimated primary production in equatorial areas. The result of using 6 h forcing on predicted ecosystem dynamics was profound, the effects persisting far beyond the hourly timescale, and having major consequences for predicted global and new production on an annual basis.

  13. Onboard Short Term Plan Viewer

    Science.gov (United States)

    Hall, Tim; LeBlanc, Troy; Ulman, Brian; McDonald, Aaron; Gramm, Paul; Chang, Li-Min; Keerthi, Suman; Kivlovitz, Dov; Hadlock, Jason

    2011-01-01

    Onboard Short Term Plan Viewer (OSTPV) is a computer program for electronic display of mission plans and timelines, both aboard the International Space Station (ISS) and in ISS ground control stations located in several countries. OSTPV was specifically designed both (1) for use within the limited ISS computing environment and (2) to be compatible with computers used in ground control stations. OSTPV supplants a prior system in which, aboard the ISS, timelines were printed on paper and incorporated into files that also contained other paper documents. Hence, the introduction of OSTPV has both reduced the consumption of resources and saved time in updating plans and timelines. OSTPV accepts, as input, the mission timeline output of a legacy, print-oriented, UNIX-based program called "Consolidated Planning System" and converts the timeline information for display in an interactive, dynamic, Windows Web-based graphical user interface that is used by both the ISS crew and ground control teams in real time. OSTPV enables the ISS crew to electronically indicate execution of timeline steps, launch electronic procedures, and efficiently report to ground control teams on the statuses of ISS activities, all by use of laptop computers aboard the ISS.

  14. The stimulation of hematosis on short-term and prolong irradiation

    International Nuclear Information System (INIS)

    Tukhtaev, T.M.

    1978-01-01

    This book studies the stimulation of hematosis on short-term and prolong irradiation, pathogenetic mechanisms of lesion and reconstruction of hematosis at critical radiation sickness, action hematosis stimulators in short-term irradiation conditions

  15. Short-term memory and dual task performance

    Science.gov (United States)

    Regan, J. E.

    1982-01-01

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

  16. Effects of short-term alendronate treatment on the three-dimensional microstructural, physical and mechanical properties of dog trabecular bone

    DEFF Research Database (Denmark)

    Hu, J; Ding, Ming; Søballe, K

    2002-01-01

    The bisphosphonate, alendronate, is well known for its potent inhibition of osteoclast-mediated bone resorption. It has been used clinically for the treatment of osteoporosis and has also recently been used to reduce osteolysis around prostheses in a canine revision model of implant loosening...... proximal humeri. These specimens were scanned using a high-resolution microcomputed tomography (micro-CT) system. From accurate data sets, three-dimensional microstructural properties were calculated and physical and mechanical properties were determined. Treatment with alendronate increased bone volume...

  17. Short-Term Motor Compensations to Denervation of Feline Soleus and Lateral Gastrocnemius Result in Preservation of Ankle Mechanical Output during Locomotion

    Science.gov (United States)

    Prilutsky, Boris I.; Maas, Huub; Bulgakova, Margarita; Hodson-Tole, Emma F.; Gregor, Robert J.

    2011-01-01

    Denervation of selected ankle extensors in animals results in locomotor changes. These changes have been suggested to permit preservation of global kinematic characteristics of the hindlimb during stance. The peak ankle joint moment is also preserved immediately after denervation of several ankle extensors in the cat, suggesting that the animal's response to peripheral nerve injury may also be aimed at preserving ankle mechanical output. We tested this hypothesis by comparing joint moments and power patterns during walking before and after denervation of soleus and lateral gastrocnemius muscles. Hindlimb kinematics, ground reaction forces and electromyographic activity of selected muscles were recorded during level, downslope (−50%) and upslope (50%) walking before and 1–3 weeks after nerve denervation. Denervation resulted in increased activity of the intact medial gastrocnemius and plantaris muscles, greater ankle dorsiflexion, smaller knee flexion, and the preservation of the peak ankle moment during stance. Surprisingly, ankle positive power generated in the propulsion phase of stance was increased (up to 50%) after denervation in all walking conditions (p ankle. The additional mechanical energy generated at the ankle during propulsion can result, in part, from increased activity of intact synergists, the use of passive tissues around the ankle and by the tendon action of ankle two-joint muscles and crural fascia. PMID:21411965

  18. Short-term effects of kinesio taping versus cervical thrust manipulation in patients with mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Saavedra-Hernández, Manuel; Castro-Sánchez, Adelaida M; Arroyo-Morales, Manuel; Cleland, Joshua A; Lara-Palomo, Inmaculada C; Fernández-de-Las-Peñas, César

    2012-08-01

    Randomized clinical trial. To compare the effectiveness of cervical spine thrust manipulation to that of Kinesio Taping applied to the neck in individuals with mechanical neck pain, using self-reported pain and disability and cervical range of motion as measures. The effectiveness of cervical manipulation has received considerable attention in the literature. However, because some patients cannot tolerate cervical thrust manipulation, alternative therapeutic options should be investigated. Eighty patients (36 women) were randomly assigned to 1 of 2 groups: the manipulation group, which received 2 cervical thrust manipulations, and the tape group, which received Kinesio Taping applied to the neck. Neck pain (11-point numeric pain rating scale), disability (Neck Disability Index), and cervical-range-of-motion data were collected at baseline and 1 week after the intervention by an assessor blinded to the treatment allocation of the patients. Mixed-model analyses of variance were used to examine the effects of the treatment on each outcome variable, with group as the between-subjects variable and time as the within-subjects variable. The primary analysis was the group-by-time interaction. No significant group-by-time interactions were found for pain (F = 1.892, P = .447) or disability (F = 0.115, P = .736). The group-by-time interaction was statistically significant for right (F = 7.317, P = .008) and left (F = 9.525, P = .003) cervical rotation range of motion, with the patients who received the cervical thrust manipulation having experienced greater improvement in cervical rotation than those treated with Kinesio Tape (Pcervical spine range of motion for flexion (F = 0.944, P = .334), extension (F = 0.122, P = .728), and right (F = 0.220, P = .650) and left (F = 0.389, P = .535) lateral flexion. Patients with mechanical neck pain who received cervical thrust manipulation or Kinesio Taping exhibited similar reductions in neck pain intensity and disability and similar

  19. Different mechanisms for the short-term effects of real versus sham transcutaneous electrical nerve stimulation (TENS) in patients with chronic pain: a pilot study.

    Science.gov (United States)

    Oosterhof, Jan; Wilder-Smith, Oliver H; Oostendorp, Rob A; Crul, Ben J

    2012-01-01

    Transcutaneous electrical nerve stimulation (TENS) has existed since the early 1970s. However, randomized placebo controlled studies show inconclusive results in the treatment of chronic pain. These results could be explained by assuming that TENS elicits a placebo response. However, in animal research TENS has been found to decrease hyperalgesia, which contradicts this assumption. The aim of this study is to use quantitative sensory testing to explore changes in pain processing during sham versus real TENS in patients with chronic pain. Patients with chronic pain (N = 20) were randomly allocated to real TENS or sham TENS application. Electrical pain thresholds (EPTs) were determined inside and outside the segment stimulated, before and after the first 20 minutes of the intervention, and after a period of 10 days of daily real/sham TENS application. Pain relief did not differ significantly for real versus sham TENS. However, by comparing time courses of EPTs, it was found that EPT values outside the segment of stimulation increased for sham TENS, whereas for real TENS these values decreased. There were, however, no differences for EPT measurements inside the segment stimulated. These results illustrate the importance of including mechanism-reflecting parameters in addition to symptoms when conducting pain research.

  20. Short-Term Intercultural Psychotherapy: Ethnographic Inquiry

    Science.gov (United States)

    Seeley, Karen M.

    2004-01-01

    This article examines the challenges specific to short-term intercultural treatments and recently developed approaches to intercultural treatments based on notions of cultural knowledge and cultural competence. The article introduces alternative approaches to short-term intercultural treatments based on ethnographic inquiry adapted for clinical…

  1. Protein tyrosine phosphatases: regulatory mechanisms.

    NARCIS (Netherlands)

    den Hertog, J.; Ostman, A.; Bohmer, F.D.

    2008-01-01

    Protein-tyrosine phosphatases are tightly controlled by various mechanisms, ranging from differential expression in specific cell types to restricted subcellular localization, limited proteolysis, post-translational modifications affecting intrinsic catalytic activity, ligand binding and

  2. Short term memory in echo state networks

    OpenAIRE

    Jaeger, H.

    2001-01-01

    The report investigates the short-term memory capacity of echo state recurrent neural networks. A quantitative measure MC of short-term memory capacity is introduced. The main result is that MC 5 N for networks with linear Output units and i.i.d. input, where N is network size. Conditions under which these maximal memory capacities are realized are described. Several theoretical and practical examples demonstrate how the short-term memory capacities of echo state networks can be exploited for...

  3. Brain oscillatory substrates of visual short-term memory capacity.

    Science.gov (United States)

    Sauseng, Paul; Klimesch, Wolfgang; Heise, Kirstin F; Gruber, Walter R; Holz, Elisa; Karim, Ahmed A; Glennon, Mark; Gerloff, Christian; Birbaumer, Niels; Hummel, Friedhelm C

    2009-11-17

    The amount of information that can be stored in visual short-term memory is strictly limited to about four items. Therefore, memory capacity relies not only on the successful retention of relevant information but also on efficient suppression of distracting information, visual attention, and executive functions. However, completely separable neural signatures for these memory capacity-limiting factors remain to be identified. Because of its functional diversity, oscillatory brain activity may offer a utile solution. In the present study, we show that capacity-determining mechanisms, namely retention of relevant information and suppression of distracting information, are based on neural substrates independent of each other: the successful maintenance of relevant material in short-term memory is associated with cross-frequency phase synchronization between theta (rhythmical neural activity around 5 Hz) and gamma (> 50 Hz) oscillations at posterior parietal recording sites. On the other hand, electroencephalographic alpha activity (around 10 Hz) predicts memory capacity based on efficient suppression of irrelevant information in short-term memory. Moreover, repetitive transcranial magnetic stimulation at alpha frequency can modulate short-term memory capacity by influencing the ability to suppress distracting information. Taken together, the current study provides evidence for a double dissociation of brain oscillatory correlates of visual short-term memory capacity.

  4. Exogenous Attention Influences Visual Short-Term Memory in Infants

    Science.gov (United States)

    Ross-Sheehy, Shannon; Oakes, Lisa M.; Luck, Steven J.

    2011-01-01

    Two experiments examined the hypothesis that developing visual attentional mechanisms influence infants' Visual Short-Term Memory (VSTM) in the context of multiple items. Five- and 10-month-old infants (N = 76) received a change detection task in which arrays of three differently colored squares appeared and disappeared. On each trial one square…

  5. Short-term memory across eye blinks.

    Science.gov (United States)

    Irwin, David E

    2014-01-01

    The effect of eye blinks on short-term memory was examined in two experiments. On each trial, participants viewed an initial display of coloured, oriented lines, then after a retention interval they viewed a test display that was either identical or different by one feature. Participants kept their eyes open throughout the retention interval on some blocks of trials, whereas on others they made a single eye blink. Accuracy was measured as a function of the number of items in the display to determine the capacity of short-term memory on blink and no-blink trials. In separate blocks of trials participants were instructed to remember colour only, orientation only, or both colour and orientation. Eye blinks reduced short-term memory capacity by approximately 0.6-0.8 items for both feature and conjunction stimuli. A third, control, experiment showed that a button press during the retention interval had no effect on short-term memory capacity, indicating that the effect of an eye blink was not due to general motoric dual-task interference. Eye blinks might instead reduce short-term memory capacity by interfering with attention-based rehearsal processes.

  6. Visual Short-Term Memory Complexity

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik

    Several recent studies have explored the nature and limits of visual short-term memory (VSTM) (e.g. Luck & Vogel, 1997). A general VSTM capacity limit of about 3 to 4 letters has been found, thus confirming results from earlier studies (e.g. Cattell, 1885; Sperling, 1960). However, Alvarez...

  7. Retrieval-Induced Inhibition in Short-Term Memory.

    Science.gov (United States)

    Kang, Min-Suk; Choi, Joongrul

    2015-07-01

    We used a visual illusion called motion repulsion as a model system for investigating competition between two mental representations. Subjects were asked to remember two random-dot-motion displays presented in sequence and then to report the motion directions for each. Remembered motion directions were shifted away from the actual motion directions, an effect similar to the motion repulsion observed during perception. More important, the item retrieved second showed greater repulsion than the item retrieved first. This suggests that earlier retrieval exerted greater inhibition on the other item being held in short-term memory. This retrieval-induced motion repulsion could be explained neither by reduced cognitive resources for maintaining short-term memory nor by continued inhibition between short-term memory representations. These results indicate that retrieval of memory representations inhibits other representations in short-term memory. We discuss mechanisms of retrieval-induced inhibition and their implications for the structure of memory. © The Author(s) 2015.

  8. Retention interval affects visual short-term memory encoding.

    Science.gov (United States)

    Bankó, Eva M; Vidnyánszky, Zoltán

    2010-03-01

    Humans can efficiently store fine-detailed facial emotional information in visual short-term memory for several seconds. However, an unresolved question is whether the same neural mechanisms underlie high-fidelity short-term memory for emotional expressions at different retention intervals. Here we show that retention interval affects the neural processes of short-term memory encoding using a delayed facial emotion discrimination task. The early sensory P100 component of the event-related potentials (ERP) was larger in the 1-s interstimulus interval (ISI) condition than in the 6-s ISI condition, whereas the face-specific N170 component was larger in the longer ISI condition. Furthermore, the memory-related late P3b component of the ERP responses was also modulated by retention interval: it was reduced in the 1-s ISI as compared with the 6-s condition. The present findings cannot be explained based on differences in sensory processing demands or overall task difficulty because there was no difference in the stimulus information and subjects' performance between the two different ISI conditions. These results reveal that encoding processes underlying high-precision short-term memory for facial emotional expressions are modulated depending on whether information has to be stored for one or for several seconds.

  9. Improving creativity performance by short-term meditation

    Science.gov (United States)

    2014-01-01

    Background One form of meditation intervention, the integrative body-mind training (IBMT) has been shown to improve attention, reduce stress and change self-reports of mood. In this paper we examine whether short-term IBMT can improve performance related to creativity and determine the role that mood may play in such improvement. Methods Forty Chinese undergraduates were randomly assigned to short-term IBMT group or a relaxation training (RT) control group. Mood and creativity performance were assessed by the Positive and Negative Affect Schedule (PANAS) and Torrance Tests of Creative Thinking (TTCT) questionnaire respectively. Results As predicted, the results indicated that short-term (30 min per day for 7 days) IBMT improved creativity performance on the divergent thinking task, and yielded better emotional regulation than RT. In addition, cross-lagged analysis indicated that both positive and negative affect may influence creativity in IBMT group (not RT group). Conclusions Our results suggested that emotion-related creativity-promoting mechanism may be attributed to short-term meditation. PMID:24645871

  10. A neuromorphic circuit mimicking biological short-term memory.

    Science.gov (United States)

    Barzegarjalali, Saeid; Parker, Alice C

    2016-08-01

    Research shows that the way we remember things for a few seconds is a different mechanism from the way we remember things for a longer time. Short-term memory is based on persistently firing neurons, whereas storing information for a longer time is based on strengthening the synapses or even forming new neural connections. Information about location and appearance of an object is segregated and processed by separate neurons. Furthermore neurons can continue firing using different mechanisms. Here, we have designed a biomimetic neuromorphic circuit that mimics short-term memory by firing neurons, using biological mechanisms to remember location and shape of an object. Our neuromorphic circuit has a hybrid architecture. Neurons are designed with CMOS 45nm technology and synapses are designed with carbon nanotubes (CNT).

  11. Auditory short-term memory in the primate auditory cortex

    OpenAIRE

    Scott, Brian H.; Mishkin, Mortimer

    2015-01-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ���working memory��� bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive sho...

  12. Short-term Memory of Deep RNN

    OpenAIRE

    Gallicchio, Claudio

    2018-01-01

    The extension of deep learning towards temporal data processing is gaining an increasing research interest. In this paper we investigate the properties of state dynamics developed in successive levels of deep recurrent neural networks (RNNs) in terms of short-term memory abilities. Our results reveal interesting insights that shed light on the nature of layering as a factor of RNN design. Noticeably, higher layers in a hierarchically organized RNN architecture results to be inherently biased ...

  13. A short-term neural network memory

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.J.T.; Wong, W.S.

    1988-12-01

    Neural network memories with storage prescriptions based on Hebb's rule are known to collapse as more words are stored. By requiring that the most recently stored word be remembered precisely, a new simple short-term neutral network memory is obtained and its steady state capacity analyzed and simulated. Comparisons are drawn with Hopfield's method, the delta method of Widrow and Hoff, and the revised marginalist model of Mezard, Nadal, and Toulouse.

  14. Analysis of the short-term overproduction capability of variable speed wind turbines

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Altin, Müfit; Margaris, Ioannis D.

    2014-01-01

    Emphasis in this article is on variable speed wind turbines (VSWTs) capability to provide short-term overproduction and better understanding of VSWTs’ mechanical and electrical limits to deliver such support. VSWTs’ short-term overproduction capability is of primary concern for the transmission...

  15. Visual dot interaction with short-term memory.

    Science.gov (United States)

    Etindele Sosso, Faustin Armel

    2017-06-01

    Many neurodegenerative diseases have a memory component. Brain structures related to memory are affected by environmental stimuli, and it is difficult to dissociate effects of all behavior of neurons. Here, visual cortex of mice was stimulated with gratings and dot, and an observation of neuronal activity before and after was made. Bandwidth, firing rate and orientation selectivity index were evaluated. A primary communication between primary visual cortex and short-term memory appeared to show an interesting path to train cognitive circuitry and investigate the basics mechanisms of the neuronal learning. The findings also suggested the interplay between primary visual cortex and short-term plasticity. The properties inside a visual target shape the perception and affect the basic encoding. Using visual cortex, it may be possible to train the memory and improve the recovery of people with cognitive disabilities or memory deficit.

  16. Short-term memory in networks of dissociated cortical neurons.

    Science.gov (United States)

    Dranias, Mark R; Ju, Han; Rajaram, Ezhilarasan; VanDongen, Antonius M J

    2013-01-30

    Short-term memory refers to the ability to store small amounts of stimulus-specific information for a short period of time. It is supported by both fading and hidden memory processes. Fading memory relies on recurrent activity patterns in a neuronal network, whereas hidden memory is encoded using synaptic mechanisms, such as facilitation, which persist even when neurons fall silent. We have used a novel computational and optogenetic approach to investigate whether these same memory processes hypothesized to support pattern recognition and short-term memory in vivo, exist in vitro. Electrophysiological activity was recorded from primary cultures of dissociated rat cortical neurons plated on multielectrode arrays. Cultures were transfected with ChannelRhodopsin-2 and optically stimulated using random dot stimuli. The pattern of neuronal activity resulting from this stimulation was analyzed using classification algorithms that enabled the identification of stimulus-specific memories. Fading memories for different stimuli, encoded in ongoing neural activity, persisted and could be distinguished from each other for as long as 1 s after stimulation was terminated. Hidden memories were detected by altered responses of neurons to additional stimulation, and this effect persisted longer than 1 s. Interestingly, network bursts seem to eliminate hidden memories. These results are similar to those that have been reported from similar experiments in vivo and demonstrate that mechanisms of information processing and short-term memory can be studied using cultured neuronal networks, thereby setting the stage for therapeutic applications using this platform.

  17. Implementation of short-term prediction

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L; Joensen, A; Giebel, G [and others

    1999-03-01

    This paper will giver a general overview of the results from a EU JOULE funded project (`Implementing short-term prediction at utilities`, JOR3-CT95-0008). Reference will be given to specialised papers where applicable. The goal of the project was to implement wind farm power output prediction systems in operational environments at a number of utilities in Europe. Two models were developed, one by Risoe and one by the Technical University of Denmark (DTU). Both prediction models used HIRLAM predictions from the Danish Meteorological Institute (DMI). (au) EFP-94; EU-JOULE. 11 refs.

  18. Is visual short-term memory depthful?

    Science.gov (United States)

    Reeves, Adam; Lei, Quan

    2014-03-01

    Does visual short-term memory (VSTM) depend on depth, as it might be if information was stored in more than one depth layer? Depth is critical in natural viewing and might be expected to affect retention, but whether this is so is currently unknown. Cued partial reports of letter arrays (Sperling, 1960) were measured up to 700 ms after display termination. Adding stereoscopic depth hardly affected VSTM capacity or decay inferred from total errors. The pattern of transposition errors (letters reported from an uncued row) was almost independent of depth and cue delay. We conclude that VSTM is effectively two-dimensional. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Auditory short-term memory activation during score reading.

    Science.gov (United States)

    Simoens, Veerle L; Tervaniemi, Mari

    2013-01-01

    Performing music on the basis of reading a score requires reading ahead of what is being played in order to anticipate the necessary actions to produce the notes. Score reading thus not only involves the decoding of a visual score and the comparison to the auditory feedback, but also short-term storage of the musical information due to the delay of the auditory feedback during reading ahead. This study investigates the mechanisms of encoding of musical information in short-term memory during such a complicated procedure. There were three parts in this study. First, professional musicians participated in an electroencephalographic (EEG) experiment to study the slow wave potentials during a time interval of short-term memory storage in a situation that requires cross-modal translation and short-term storage of visual material to be compared with delayed auditory material, as it is the case in music score reading. This delayed visual-to-auditory matching task was compared with delayed visual-visual and auditory-auditory matching tasks in terms of EEG topography and voltage amplitudes. Second, an additional behavioural experiment was performed to determine which type of distractor would be the most interfering with the score reading-like task. Third, the self-reported strategies of the participants were also analyzed. All three parts of this study point towards the same conclusion according to which during music score reading, the musician most likely first translates the visual score into an auditory cue, probably starting around 700 or 1300 ms, ready for storage and delayed comparison with the auditory feedback.

  20. Cardioprotective Signature of Short-Term Caloric Restriction.

    Directory of Open Access Journals (Sweden)

    Hossein Noyan

    Full Text Available To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR.Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we reveal the pathways that are modulated by short-term CR, which are associated with protection of the mouse heart from ischemia.Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL diet with free access to regular chow, or CR, receiving 30% less food for 7 days (d, prior to myocardial infarction (MI via permanent coronary ligation. At d8, the left ventricles (LV of AL and CR mice were collected for Western blot, mRNA and microRNA (miR analyses to identify cardioprotective gene expression signatures. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI.This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01. mRNA and miR profiles pre-MI (N=5/group identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM. Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1α, cytochrome C and cyclooxygenase (COX IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38. CR regimen was also associated with reduced protein abundance of cleaved caspase 3 in the infarcted heart and improved cardiac function.

  1. Short term depression unmasks the ghost frequency.

    Directory of Open Access Journals (Sweden)

    Tjeerd V Olde Scheper

    Full Text Available Short Term Plasticity (STP has been shown to exist extensively in synapses throughout the brain. Its function is more or less clear in the sense that it alters the probability of synaptic transmission at short time scales. However, it is still unclear what effect STP has on the dynamics of neural networks. We show, using a novel dynamic STP model, that Short Term Depression (STD can affect the phase of frequency coded input such that small networks can perform temporal signal summation and determination with high accuracy. We show that this property of STD can readily solve the problem of the ghost frequency, the perceived pitch of a harmonic complex in absence of the base frequency. Additionally, we demonstrate that this property can explain dynamics in larger networks. By means of two models, one of chopper neurons in the Ventral Cochlear Nucleus and one of a cortical microcircuit with inhibitory Martinotti neurons, it is shown that the dynamics in these microcircuits can reliably be reproduced using STP. Our model of STP gives important insights into the potential roles of STP in self-regulation of cortical activity and long-range afferent input in neuronal microcircuits.

  2. Short-term energy outlook, July 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The Energy Information Administration (EIA) prepares The Short-Term Energy Outlook (energy supply, demand, and price projections) monthly for distribution on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. In addition, printed versions of the report are available to subscribers in January, April, July and October. The forecast period for this issue of the Outlook extends from July 1998 through December 1999. Values for second quarter of 1998 data, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the July 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. 28 figs., 19 tabs.

  3. Short-term energy outlook, January 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    The Energy Information Administration (EIA) prepares the Short-Term Energy Outlook (energy supply, demand, and price projections) monthly. The forecast period for this issue of the Outlook extends from January 1999 through December 2000. Data values for the fourth quarter 1998, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the January 1999 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 28 figs., 19 tabs.

  4. Measuring Short-term Energy Security

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Ensuring energy security has been at the centre of the IEA mission since its inception, following the oil crises of the early 1970s. While the security of oil supplies remains important, contemporary energy security policies must address all energy sources and cover a comprehensive range of natural, economic and political risks that affect energy sources, infrastructures and services. In response to this challenge, the IEA is currently developing a Model Of Short-term Energy Security (MOSES) to evaluate the energy security risks and resilience capacities of its member countries. The current version of MOSES covers short-term security of supply for primary energy sources and secondary fuels among IEA countries. It also lays the foundation for analysis of vulnerabilities of electricity and end-use energy sectors. MOSES contains a novel approach to analysing energy security, which can be used to identify energy security priorities, as a starting point for national energy security assessments and to track the evolution of a country's energy security profile. By grouping together countries with similar 'energy security profiles', MOSES depicts the energy security landscape of IEA countries. By extending the MOSES methodology to electricity security and energy services in the future, the IEA aims to develop a comprehensive policy-relevant perspective on global energy security. This Brochure provides and overview of the analysis and results. Readers interested in an in-depth discussion of methodology are referred to the MOSES Working Paper.

  5. Short Term Airing by Natural Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per; Perino, M.

    2010-01-01

    The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. Among the available ventilation strategies...... that are currently available, buoyancy driven, single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and Indoor Air Quality (IAQ) control. However, to promote a wider distribution of these systems an improvement in the knowledge of their working...... airflow rate, ventilation efficiency, thermal comfort and dynamic temperature conditions. A suitable laboratory test rig was developed to perform extensive experimental analyses of the phenomenon under controlled and repeatable conditions. The results showed that short-term window airing is very effective...

  6. Short-term forecasting of internal migration.

    Science.gov (United States)

    Frees, E W

    1993-11-01

    A new methodological approach to the forecasting of short-term trends in internal migration in the United States is introduced. "Panel-data (or longitudinal-data) models are used to represent the relationship between destination-specific out-migration and several explanatory variables. The introduction of this methodology into the migration literature is possible because of some new and improved databases developed by the U.S. Bureau of the Census.... Data from the Bureau of Economic Analysis are used to investigate the incorporation of exogenous factors as variables in the model." The exogenous factors considered include employment and unemployment, income, population size of state, and distance between states. The author concludes that "when one...includes additional parameters that are estimable in longitudinal-data models, it turns out that there is little additional information in the exogenous factors that is useful for forecasting." excerpt

  7. Economics of solar energy: Short term costing

    Science.gov (United States)

    Klee, H.

    The solar economics based on life cycle costs are refuted as both imaginary and irrelevant. It is argued that predicting rates of inflation and fuel escalation, expected life, maintenance costs, and legislation over the next ten to twenty years is pure guesswork. Furthermore, given the high mobility level of the U.S. population, the average consumer is skeptical of long run arguments which will pay returns only to the next owners. In the short term cost analysis, the house is sold prior to the end of the expected life of the system. The cash flow of the seller and buyer are considered. All the relevant factors, including the federal tax credit and the added value of the house because of the solar system are included.

  8. Short-term plasticity in auditory cognition.

    Science.gov (United States)

    Jääskeläinen, Iiro P; Ahveninen, Jyrki; Belliveau, John W; Raij, Tommi; Sams, Mikko

    2007-12-01

    Converging lines of evidence suggest that auditory system short-term plasticity can enable several perceptual and cognitive functions that have been previously considered as relatively distinct phenomena. Here we review recent findings suggesting that auditory stimulation, auditory selective attention and cross-modal effects of visual stimulation each cause transient excitatory and (surround) inhibitory modulations in the auditory cortex. These modulations might adaptively tune hierarchically organized sound feature maps of the auditory cortex (e.g. tonotopy), thus filtering relevant sounds during rapidly changing environmental and task demands. This could support auditory sensory memory, pre-attentive detection of sound novelty, enhanced perception during selective attention, influence of visual processing on auditory perception and longer-term plastic changes associated with perceptual learning.

  9. Attentional priorities and access to short-term memory

    DEFF Research Database (Denmark)

    Gillebert, Celine; Dyrholm, Mads; Vangkilde, Signe Allerup

    2012-01-01

    The intraparietal sulcus (IPS) has been implicated in selective attention as well as visual short-term memory (VSTM). To contrast mechanisms of target selection, distracter filtering, and access to VSTM, we combined behavioral testing, computational modeling and functional magnetic resonance......, thereby displaying a significant interaction between the two factors. The interaction between target and distracter set size in IPS could not be accounted for by a simple explanation in terms of number of items accessing VSTM. Instead, it led us to a model where items accessing VSTM receive differential...

  10. Short-term memory in zebrafish (Danio rerio).

    Science.gov (United States)

    Jia, Jason; Fernandes, Yohaan; Gerlai, Robert

    2014-08-15

    Learning and memory represent perhaps the most complex behavioral phenomena. Although their underlying mechanisms have been extensively analyzed, only a fraction of the potential molecular components have been identified. The zebrafish has been proposed as a screening tool with which mechanisms of complex brain functions may be systematically uncovered. However, as a relative newcomer in behavioral neuroscience, the zebrafish has not been well characterized for its cognitive and mnemonic features, thus learning and/or memory screens with adults have not been feasible. Here we study short-term memory of adult zebrafish. We show animated images of conspecifics (the stimulus) to the experimental subject during 1 min intervals on ten occasions separated by different (2, 4, 8 or 16 min long) inter-stimulus intervals (ISI), a between subject experimental design. We quantify the distance of the subject from the image presentation screen during each stimulus presentation interval, during each of the 1-min post-stimulus intervals immediately following the stimulus presentations and during each of the 1-min intervals furthest away from the last stimulus presentation interval and just before the next interval (pre-stimulus interval), respectively. Our results demonstrate significant retention of short-term memory even in the longest ISI group but suggest no acquisition of reference memory. Because in the employed paradigm both stimulus presentation and behavioral response quantification is computer automated, we argue that high-throughput screening for drugs or mutations that alter short-term memory performance of adult zebrafish is now becoming feasible. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Evaluation of Short Term Memory Span Function In Children

    OpenAIRE

    Barış ERGÜL; Arzu ALTIN YAVUZ; Ebru GÜNDOĞAN AŞIK

    2016-01-01

    Although details of the information encoded in the short-term memory where it is stored temporarily be recorded in the working memory in the next stage. Repeating the information mentally makes it remain in memory for a long time. Studies investigating the relationship between short-term memory and reading skills that are carried out to examine the relationship between short-term memory processes and reading comprehension. In this study information coming to short-term memory and the factors ...

  12. In Search of Decay in Verbal Short-Term Memory

    Science.gov (United States)

    Berman, Marc G.; Jonides, John; Lewis, Richard L.

    2009-01-01

    Is forgetting in the short term due to decay with the mere passage of time, interference from other memoranda, or both? Past research on short-term memory has revealed some evidence for decay and a plethora of evidence showing that short-term memory is worsened by interference. However, none of these studies has directly contrasted decay and…

  13. Short-Term Saved Leave Scheme

    CERN Multimedia

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new implementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme a...

  14. Short-Term Saved Leave Scheme

    CERN Multimedia

    HR Department

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new im-plementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme ...

  15. Short-term energy outlook, April 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    The forecast period for this issue of the Outlook extends from April 1999 through December 2000. Data values for the first quarter 1999, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the April 1999 version of the Short-Term Integrated forecasting system (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 25 figs., 19 tabs.

  16. Continuity of Landsat observations: Short term considerations

    Science.gov (United States)

    Wulder, Michael A.; White, Joanne C.; Masek, Jeffery G.; Dwyer, John L.; Roy, David P.

    2011-01-01

    As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat data for a period of time until the 2012 launch. Although the potential risk of a component failure increases the longer the sensor's design life is exceeded, the possible gap in Landsat data acquisition is reduced with each passing day and the risk of Landsat imagery being unavailable diminishes for all except a handful of applications that are particularly data demanding. Advances in Landsat data compositing and fusion are providing opportunities to address issues associated with Landsat-7 SLC-off imagery and to mitigate a potential acquisition gap through the integration of imagery from different sensors. The latter will likely also provide short-term, regional solutions to application-specific needs for the continuity of Landsat-like observations. Our goal in this communication is not to minimize the community's concerns regarding a gap in Landsat observations, but rather to clarify how the current situation has evolved and provide an up-to-date understanding of the circumstances, implications, and mitigation options related to a potential gap in the Landsat data record.

  17. Fuzzy approach for short term load forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Chenthur Pandian, S.; Duraiswamy, K.; Kanagaraj, N. [Electrical and Electronics Engg., K.S. Rangasamy College of Technology, Tiruchengode 637209, Tamil Nadu (India); Christober Asir Rajan, C. [Department of Electrical and Electronics Engineering, Pondicherry Engineering College, Pondicherry (India)

    2006-04-15

    The main objective of short term load forecasting (STLF) is to provide load predictions for generation scheduling, economic load dispatch and security assessment at any time. The STLF is needed to supply necessary information for the system management of day-to-day operations and unit commitment. In this paper, the 'time' and 'temperature' of the day are taken as inputs for the fuzzy logic controller and the 'forecasted load' is the output. The input variable 'time' has been divided into eight triangular membership functions. The membership functions are Mid Night, Dawn, Morning, Fore Noon, After Noon, Evening, Dusk and Night. Another input variable 'temperature' has been divided into four triangular membership functions. They are Below Normal, Normal, Above Normal and High. The 'forecasted load' as output has been divided into eight triangular membership functions. They are Very Low, Low, Sub Normal, Moderate Normal, Normal, Above Normal, High and Very High. Case studies have been carried out for the Neyveli Thermal Power Station Unit-II (NTPS-II) in India. The fuzzy forecasted load values are compared with the conventional forecasted values. The forecasted load closely matches the actual one within +/-3%. (author)

  18. Short-term natural gas consumption forecasting

    International Nuclear Information System (INIS)

    Potocnik, P.; Govekar, E.; Grabec, I.

    2007-01-01

    Energy forecasting requirements for Slovenia's natural gas market were investigated along with the cycles of natural gas consumption. This paper presented a short-term natural gas forecasting approach where the daily, weekly and yearly gas consumption were analyzed and the information obtained was incorporated into the forecasting model for hourly forecasting for the next day. The natural gas market depends on forecasting in order to optimize the leasing of storage capacities. As such, natural gas distribution companies have an economic incentive to accurately forecast their future gas consumption. The authors proposed a forecasting model with the following properties: two submodels for the winter and summer seasons; input variables including past consumption data, weather data, weather forecasts and basic cycle indexes; and, a hierarchical forecasting structure in which a daily model was used as the basis, with the hourly forecast obtained by modeling the relative daily profile. This proposed method was illustrated by a forecasting example for Slovenia's natural gas market. 11 refs., 11 figs

  19. Robust Short-Term Memory without Synaptic Learning

    Science.gov (United States)

    Johnson, Samuel; Marro, J.; Torres, Joaquín J.

    2013-01-01

    Short-term memory in the brain cannot in general be explained the way long-term memory can – as a gradual modification of synaptic weights – since it takes place too quickly. Theories based on some form of cellular bistability, however, do not seem able to account for the fact that noisy neurons can collectively store information in a robust manner. We show how a sufficiently clustered network of simple model neurons can be instantly induced into metastable states capable of retaining information for a short time (a few seconds). The mechanism is robust to different network topologies and kinds of neural model. This could constitute a viable means available to the brain for sensory and/or short-term memory with no need of synaptic learning. Relevant phenomena described by neurobiology and psychology, such as local synchronization of synaptic inputs and power-law statistics of forgetting avalanches, emerge naturally from this mechanism, and we suggest possible experiments to test its viability in more biological settings. PMID:23349664

  20. Robust short-term memory without synaptic learning.

    Directory of Open Access Journals (Sweden)

    Samuel Johnson

    Full Text Available Short-term memory in the brain cannot in general be explained the way long-term memory can--as a gradual modification of synaptic weights--since it takes place too quickly. Theories based on some form of cellular bistability, however, do not seem able to account for the fact that noisy neurons can collectively store information in a robust manner. We show how a sufficiently clustered network of simple model neurons can be instantly induced into metastable states capable of retaining information for a short time (a few seconds. The mechanism is robust to different network topologies and kinds of neural model. This could constitute a viable means available to the brain for sensory and/or short-term memory with no need of synaptic learning. Relevant phenomena described by neurobiology and psychology, such as local synchronization of synaptic inputs and power-law statistics of forgetting avalanches, emerge naturally from this mechanism, and we suggest possible experiments to test its viability in more biological settings.

  1. Robust short-term memory without synaptic learning.

    Science.gov (United States)

    Johnson, Samuel; Marro, J; Torres, Joaquín J

    2013-01-01

    Short-term memory in the brain cannot in general be explained the way long-term memory can--as a gradual modification of synaptic weights--since it takes place too quickly. Theories based on some form of cellular bistability, however, do not seem able to account for the fact that noisy neurons can collectively store information in a robust manner. We show how a sufficiently clustered network of simple model neurons can be instantly induced into metastable states capable of retaining information for a short time (a few seconds). The mechanism is robust to different network topologies and kinds of neural model. This could constitute a viable means available to the brain for sensory and/or short-term memory with no need of synaptic learning. Relevant phenomena described by neurobiology and psychology, such as local synchronization of synaptic inputs and power-law statistics of forgetting avalanches, emerge naturally from this mechanism, and we suggest possible experiments to test its viability in more biological settings.

  2. Temporal grouping effects in musical short-term memory.

    Science.gov (United States)

    Gorin, Simon; Mengal, Pierre; Majerus, Steve

    2018-07-01

    Recent theoretical accounts of verbal and visuo-spatial short-term memory (STM) have proposed the existence of domain-general mechanisms for the maintenance of serial order information. These accounts are based on the observation of similar behavioural effects across several modalities, such as temporal grouping effects. Across two experiments, the present study aimed at extending these findings, by exploring a STM modality that has received little interest so far, STM for musical information. Given its inherent rhythmic, temporal and serial organisation, the musical domain is of interest for investigating serial order STM processes such as temporal grouping. In Experiment 1, the data did not allow to determine the presence or the absence of temporal grouping effects. In Experiment 2, we observed that temporal grouping of tone sequences during encoding improves short-term recognition for serially presented probe tones. Furthermore, the serial position curves included micro-primacy and micro-recency effects, which are the hallmark characteristic of temporal grouping. Our results suggest that the encoding of serial order information in musical STM may be supported by temporal positional coding mechanisms similar to those reported in the verbal domain.

  3. Short-term memory binding deficits in Alzheimer's disease.

    Science.gov (United States)

    Parra, Mario A; Abrahams, Sharon; Fabi, Katia; Logie, Robert; Luzzi, Simona; Della Sala, Sergio

    2009-04-01

    mechanisms responsible for holding integrated objects in verbal short-term memory.

  4. Why do short term workers have high mortality?

    DEFF Research Database (Denmark)

    Kolstad, Henrik; Olsen, Jørn

    1999-01-01

    or violence, the rate ratios for short term employment were 2.30 (95% Cl 1.74-3.06) and 1.86 (95% Cl 1.35-2.56), respectively. An unhealthy lifestyle may also be a determinant of short term employment. While it is possible in principle to adjust for lifestyle factors if proper data are collected, the health......Increased mortality is often reported among workers in short term employment. This may indicate either a health-related selection process or the presence of different lifestyle or social conditions among short term workers. The authors studied these two aspects of short term employment among 16...

  5. Short term benefits for laparoscopic colorectal resection.

    Science.gov (United States)

    Schwenk, W; Haase, O; Neudecker, J; Müller, J M

    2005-07-20

    Colorectal resections are common surgical procedures all over the world. Laparoscopic colorectal surgery is technically feasible in a considerable amount of patients under elective conditions. Several short-term benefits of the laparoscopic approach to colorectal resection (less pain, less morbidity, improved reconvalescence and better quality of life) have been proposed. This review compares laparoscopic and conventional colorectal resection with regards to possible benefits of the laparoscopic method in the short-term postoperative period (up to 3 months post surgery). We searched MEDLINE, EMBASE, CancerLit, and the Cochrane Central Register of Controlled Trials for the years 1991 to 2004. We also handsearched the following journals from 1991 to 2004: British Journal of Surgery, Archives of Surgery, Annals of Surgery, Surgery, World Journal of Surgery, Disease of Colon and Rectum, Surgical Endoscopy, International Journal of Colorectal Disease, Langenbeck's Archives of Surgery, Der Chirurg, Zentralblatt für Chirurgie, Aktuelle Chirurgie/Viszeralchirurgie. Handsearch of abstracts from the following society meetings from 1991 to 2004: American College of Surgeons, American Society of Colorectal Surgeons, Royal Society of Surgeons, British Assocation of Coloproctology, Surgical Association of Endoscopic Surgeons, European Association of Endoscopic Surgeons, Asian Society of Endoscopic Surgeons. All randomised-controlled trial were included regardless of the language of publication. No- or pseudorandomised trials as well as studies that followed patient's preferences towards one of the two interventions were excluded, but listed separately. RCT presented as only an abstract were excluded. Results were extracted from papers by three observers independently on a predefined data sheet. Disagreements were solved by discussion. 'REVMAN 4.2' was used for statistical analysis. Mean differences (95% confidence intervals) were used for analysing continuous variables. If

  6. Distraction in Verbal Short-Term Memory: Insights from Developmental Differences

    OpenAIRE

    Elliott, Emily; Hughes, Robert W.; Briganti, A; Joseph, Tanya Nicolette; Marsh, John Everett; Macken, William J.

    2016-01-01

    The contribution of two mechanisms of auditory distraction in verbal serial short-term memory-interference with the serial rehearsal processes used to support short-term recall and general attentional diversion-was investigated by exploiting differences in auditory distraction in children and adults. Experiment 1 showed that serial rehearsal plays a role in children's as well as adults' distractibility: Auditory distraction from irrelevant speech was greater for both children and adults as th...

  7. Regulatory capital requirements and bail in mechanisms

    NARCIS (Netherlands)

    Joosen, B.P.M.; Haentjens, M.; Wessels, B.

    2015-01-01

    With the introduction of the Capital Requirements Regulation (CRR) in the European Union, the qualitative requirements for bank regulatory capital have changed. These changes aim at implementing in Europe the Basel III principles for better bank capital that is able to absorb losses of banks,

  8. Hydroxychloroquine retinopathy after short-term therapy.

    Science.gov (United States)

    Phillips, Brandon N; Chun, Dal W

    2014-01-01

    To report an unusual case of hydroxychloroquine toxicity after short-term therapy. Observational case report. A 56-year-old woman presented to the Ophthalmology Clinic at Walter Reed Army Medical Center (WRAMC) with a 6-month history of gradually decreasing vision in both eyes. The patient had been taking hydroxychloroquine for the preceding 48 months for the treatment of rheumatoid arthritis. Examination of the posterior segment revealed bilateral "bull's eye" macular lesions. Fundus autofluorescence revealed hyperfluorescence of well-defined bull's eye lesions in both eyes. Optical coherence tomography revealed corresponding parafoveal atrophy with a loss of the retinal inner segment/outer segment junction. Humphrey visual field 10-2 white showed significant central and paracentral defects with a generalized depression. The patient was on a standard dose of 400 mg daily, which was above her ideal dose. The patient had no history of kidney or liver dysfunction. There were no known risk factors but there were several possible confounding factors. The patient was started on high-dose nabumetone, a nonsteroidal antiinflammatory drug, at the same time she was started on hydroxychloroquine. She also reported taking occasional ibuprofen. Retinal toxicity from chloroquine has been recognized for decades with later reports showing retinopathy from long-term hydroxychloroquine (Plaquenil) use for the treatment of antiinflammatory diseases. Hydroxychloroquine is now widely used and retinal toxicity is relatively uncommon. However, it can cause serious vision loss and is usually irreversible. The risk of hydroxychloroquine toxicity rises to nearly 1% with a total cumulative dose of 1,000 g, which is ∼5 years to 7 years of normal use. Toxicity is rare under this dose. For this reason, the American Academy of Ophthalmology has revised its recommendations such that annual screenings begin 5 years after therapy with hydroxychloroquine has begun unless there are known risk

  9. The Role of Short-term Consolidation in Memory Persistence

    OpenAIRE

    Timothy J. Ricker

    2015-01-01

    Short-term memory, often described as working memory, is one of the most fundamental information processing systems of the human brain. Short-term memory function is necessary for language, spatial navigation, problem solving, and many other daily activities. Given its importance to cognitive function, understanding the architecture of short-term memory is of crucial importance to understanding human behavior. Recent work from several laboratories investigating the entry of information into s...

  10. Short-Term Memory and Aphasia: From Theory to Treatment.

    Science.gov (United States)

    Minkina, Irene; Rosenberg, Samantha; Kalinyak-Fliszar, Michelene; Martin, Nadine

    2017-02-01

    This article reviews existing research on the interactions between verbal short-term memory and language processing impairments in aphasia. Theoretical models of short-term memory are reviewed, starting with a model assuming a separation between short-term memory and language, and progressing to models that view verbal short-term memory as a cognitive requirement of language processing. The review highlights a verbal short-term memory model derived from an interactive activation model of word retrieval. This model holds that verbal short-term memory encompasses the temporary activation of linguistic knowledge (e.g., semantic, lexical, and phonological features) during language production and comprehension tasks. Empirical evidence supporting this model, which views short-term memory in the context of the processes it subserves, is outlined. Studies that use a classic measure of verbal short-term memory (i.e., number of words/digits correctly recalled in immediate serial recall) as well as those that use more intricate measures (e.g., serial position effects in immediate serial recall) are discussed. Treatment research that uses verbal short-term memory tasks in an attempt to improve language processing is then summarized, with a particular focus on word retrieval. A discussion of the limitations of current research and possible future directions concludes the review. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. Auditory short-term memory in the primate auditory cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

  12. Short-term sleep deprivation stimulates hippocampal neurogenesis in rats following global cerebral ischemia/reperfusion.

    Directory of Open Access Journals (Sweden)

    Oumei Cheng

    Full Text Available Sleep deprivation (SD plays a complex role in central nervous system (CNS diseases. Recent studies indicate that short-term SD can affect the extent of ischemic damage. The aim of this study was to investigate whether short-term SD could stimulate hippocampal neurogenesis in a rat model of global cerebral ischemia/reperfusion (GCIR.One hundred Sprague-Dawley rats were randomly divided into Sham, GCIR and short-term SD groups based on different durations of SD; the short-term SD group was randomly divided into three subgroups: the GCIR+6hSD*3d-treated, GCIR+12hSD-treated and GCIR+12hSD*3d-treated groups. The GCIR rat model was induced via the bilateral occlusion of the common carotid arteries and hemorrhagic hypotension. The rats were sleep-deprived starting at 48 h following GCIR. A Morris water maze test was used to assess learning and memory ability; cell proliferation and differentiation were analyzed via 5-bromodeoxyuridine (BrdU and neuron-specific enolase (NSE, respectively, at 14 and 28 d; the expression of hippocampal BDNF was measured after 7 d.The different durations of short-term SD designed in our experiment exhibited improvement in cognitive function as well as increased hippocampal BDNF expression. Additionally, the short-term SD groups also showed an increased number of BrdU- and BrdU/NSE-positive cells compared with the GCIR group. Of the three short-term SD groups, the GCIR+12hSD*3d-treated group experienced the most substantial beneficial effects.Short-term SD, especially the GCIR+12hSD*3d-treated method, stimulates neurogenesis in the hippocampal dentate gyrus (DG of rats that undergo GCIR, and BDNF may be an underlying mechanism in this process.

  13. [Short-term memory characteristics of vibration intensity tactile perception on human wrist].

    Science.gov (United States)

    Hao, Fei; Chen, Li-Juan; Lu, Wei; Song, Ai-Guo

    2014-12-25

    In this study, a recall experiment and a recognition experiment were designed to assess the human wrist's short-term memory characteristics of tactile perception on vibration intensity, by using a novel homemade vibrotactile display device based on the spatiotemporal combination vibration of multiple micro vibration motors as a test device. Based on the obtained experimental data, the short-term memory span, recognition accuracy and reaction time of vibration intensity were analyzed. From the experimental results, some important conclusions can be made: (1) The average short-term memory span of tactile perception on vibration intensity is 3 ± 1 items; (2) The greater difference between two adjacent discrete intensities of vibrotactile stimulation is defined, the better average short-term memory span human wrist gets; (3) There is an obvious difference of the average short-term memory span on vibration intensity between the male and female; (4) The mechanism of information extraction in short-term memory of vibrotactile display is to traverse the scanning process by comparison; (5) The recognition accuracy and reaction time performance of vibrotactile display compares unfavourably with that of visual and auditory. The results from this study are important for designing vibrotactile display coding scheme.

  14. Prospective testing of Coulomb short-term earthquake forecasts

    Science.gov (United States)

    Jackson, D. D.; Kagan, Y. Y.; Schorlemmer, D.; Zechar, J. D.; Wang, Q.; Wong, K.

    2009-12-01

    Earthquake induced Coulomb stresses, whether static or dynamic, suddenly change the probability of future earthquakes. Models to estimate stress and the resulting seismicity changes could help to illuminate earthquake physics and guide appropriate precautionary response. But do these models have improved forecasting power compared to empirical statistical models? The best answer lies in prospective testing in which a fully specified model, with no subsequent parameter adjustments, is evaluated against future earthquakes. The Center of Study of Earthquake Predictability (CSEP) facilitates such prospective testing of earthquake forecasts, including several short term forecasts. Formulating Coulomb stress models for formal testing involves several practical problems, mostly shared with other short-term models. First, earthquake probabilities must be calculated after each “perpetrator” earthquake but before the triggered earthquakes, or “victims”. The time interval between a perpetrator and its victims may be very short, as characterized by the Omori law for aftershocks. CSEP evaluates short term models daily, and allows daily updates of the models. However, lots can happen in a day. An alternative is to test and update models on the occurrence of each earthquake over a certain magnitude. To make such updates rapidly enough and to qualify as prospective, earthquake focal mechanisms, slip distributions, stress patterns, and earthquake probabilities would have to be made by computer without human intervention. This scheme would be more appropriate for evaluating scientific ideas, but it may be less useful for practical applications than daily updates. Second, triggered earthquakes are imperfectly recorded following larger events because their seismic waves are buried in the coda of the earlier event. To solve this problem, testing methods need to allow for “censoring” of early aftershock data, and a quantitative model for detection threshold as a function of

  15. High-Strength Ultra-Fine-Grained Hypereutectic Al-Si-Fe-X (X = Cr,Mn) Alloys Prepared by Short-Term Mechanical Alloying and Spark Plasma Sintering

    Czech Academy of Sciences Publication Activity Database

    Průša, F.; Bláhová, M.; Vojtěch, D.; Kučera, V.; Bernatiková, A.; Kubatík, Tomáš František; Michalcová, A.

    2016-01-01

    Roč. 9, č. 12 (2016), č. článku 973. ISSN 1996-1944 Institutional support: RVO:61389021 Keywords : mechanical alloying * spark plasma sintering * microstructure * mechanical properties Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 2.654, year: 2016 http://www.mdpi.com/1996-1944/9/12/973

  16. 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

  17. Short-term energy outlook, annual supplement 1994

    International Nuclear Information System (INIS)

    1994-08-01

    The Short-Term Energy Outlook Annual Supplement (Supplement) is published once a year as a complement to the Short-Term Energy Outlook (Outlook), Quarterly Projections. The purpose of the Supplement is to review the accuracy of the forecasts published in the Outlook, make comparisons with other independent energy forecasts, and examine current energy topics that affect the forecasts

  18. Pediatric polytrauma : Short-term and long-term outcomes

    NARCIS (Netherlands)

    vanderSluis, CK; Kingma, J; Eisma, WH; tenDuis, HJ

    Objective: To assess the short-term and long-term outcomes of pediatric polytrauma patients and to analyze the extent to which short-term outcomes can predict long-term outcomes. Materials and Methods: Ail pediatric polytrauma patients (Injury Severity Score of greater than or equal to 16, less than

  19. Comparison of Sugammadex and Neostigmine in Short Term Surgery

    Directory of Open Access Journals (Sweden)

    Fatih Koc

    2014-03-01

    Full Text Available Aim: This study compared the efficacy and cost effectivines of sugammadex and neostigmine for reversal of neuromuscular blockade induced by rocuronium for short term elective surgery. Material and Method: After written informed consent, 33 patients aged 18%u201365, ASA I-III, who were undergoing short term surgery (

  20. Short-Term Group Treatment for Adult Children of Alcoholics.

    Science.gov (United States)

    Cooper, Alvin; McCormack, WIlliam A.

    1992-01-01

    Adult children of alcoholics (n=24) were tested on measures of loneliness, anxiety, hostility, depression, and interpersonal dependency before and after participation in short-term group therapy. Highly significant test score changes supported effectiveness of individual therapy in short-term groups. (Author/NB)

  1. Short-term energy outlook annual supplement, 1993

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-08-06

    The Short-Term Energy Outlook Annual Supplement (supplement) is published once a year as a complement to the Short-Term Energy Outlook (Outlook), Quarterly Projections. The purpose of the Supplement is to review the accuracy of the forecasts published in the Outlook, make comparisons with other independent energy forecasts, and examine current energy topics that affect the forecasts.

  2. Short-Term Robustness of Production Management Systems : New Methodology

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; Gaury, E.G.A.

    2000-01-01

    This paper investigates the short-term robustness of production planning and control systems. This robustness is defined here as the systems ability to maintain short-term service probabilities (i.e., the probability that the fill rate remains within a prespecified range), in a variety of

  3. Short-Term Reciprocity in Late Parent-Child Relationships

    Science.gov (United States)

    Leopold, Thomas; Raab, Marcel

    2011-01-01

    Long-term concepts of parent-child reciprocity assume that the amount of support given and received is only balanced in a generalized fashion over the life course. We argue that reciprocity in parent-child relationships also operates in the short term. Our analysis of short-term reciprocity focuses on concurrent exchange in its main upward and…

  4. Epigenetic Regulatory Mechanisms Induced by Resveratrol

    Directory of Open Access Journals (Sweden)

    Guilherme Felipe Santos Fernandes

    2017-11-01

    Full Text Available Resveratrol (RVT is one of the main natural compounds studied worldwide due to its potential therapeutic use in the treatment of many diseases, including cancer, diabetes, cardiovascular diseases, neurodegenerative diseases and metabolic disorders. Nevertheless, the mechanism of action of RVT in all of these conditions is not completely understood, as it can modify not only biochemical pathways but also epigenetic mechanisms. In this paper, we analyze the biological activities exhibited by RVT with a focus on the epigenetic mechanisms, especially those related to DNA methyltransferase (DNMT, histone deacetylase (HDAC and lysine-specific demethylase-1 (LSD1.

  5. A POSTSYNAPTIC ROLE FOR SHORT-TERM NEURONAL FACILITATION IN DENDRITIC SPINES

    Directory of Open Access Journals (Sweden)

    Sunggu Yang

    2016-09-01

    Full Text Available Synaptic plasticity is a fundamental component of information processing in the brain. Presynaptic facilitation in response to repetitive stimuli, often referred to as paired-pulse facilitation (PPF, is a dominant form of short-term synaptic plasticity. Recently, an additional cellular mechanism for short-term facilitation (short-term postsynaptic plasticity has been proposed. While a dendritic mechanism was described in hippocampus, its expression has not yet been demonstrated at the levels of the spine. Furthermore, it is unknown whether the mechanism can be expressed in other brain regions, such as sensory cortex. Here, we demonstrated that a postsynaptic response can be facilitated by prior spine excitation in both hippocampal and cortical neurons, using 3D digital holography and two-photon calcium imaging. The coordinated action of pre- and post-synaptic plasticity may provide a more thorough account of information processing in the brain.

  6. Distinct transmitter release properties determine differences in short-term plasticity at functional and silent synapses.

    Science.gov (United States)

    Cabezas, Carolina; Buño, Washington

    2006-05-01

    Recent evidence suggests that functional and silent synapses are not only postsynaptically different but also presynaptically distinct. The presynaptic differences may be of functional importance in memory formation because a proposed mechanism for long-term potentiation is the conversion of silent synapses into functional ones. However, there is little direct experimentally evidence of these differences. We have investigated the transmitter release properties of functional and silent Schaffer collateral synapses and show that on the average functional synapses displayed a lower percentage of failures and higher excitatory postsynaptic current (EPSC) amplitudes than silent synapses at +60 mV. Moreover, functional but not silent synapses show paired-pulse facilitation (PPF) at +60 mV and thus presynaptic short-term plasticity will be distinct in the two types of synapse. We examined whether intraterminal endoplasmic reticulum Ca2+ stores influenced the release properties of these synapses. Ryanodine (100 microM) and thapsigargin (1 microM) increased the percentage of failures and decreased both the EPSC amplitude and PPF in functional synapses. Caffeine (10 mM) had the opposite effects. In contrast, silent synapses were insensitive to both ryanodine and caffeine. Hence we have identified differences in the release properties of functional and silent synapses, suggesting that synaptic terminals of functional synapses express regulatory molecular mechanisms that are absent in silent synapses.

  7. Verbal Short-Term Memory Span in Speech-Disordered Children: Implications for Articulatory Coding in Short-Term Memory.

    Science.gov (United States)

    Raine, Adrian; And Others

    1991-01-01

    Children with speech disorders had lower short-term memory capacity and smaller word length effect than control children. Children with speech disorders also had reduced speech-motor activity during rehearsal. Results suggest that speech rate may be a causal determinant of verbal short-term memory capacity. (BC)

  8. Evaluation of Short Term Memory Span Function In Children

    Directory of Open Access Journals (Sweden)

    Barış ERGÜL

    2016-12-01

    Full Text Available Although details of the information encoded in the short-term memory where it is stored temporarily be recorded in the working memory in the next stage. Repeating the information mentally makes it remain in memory for a long time. Studies investigating the relationship between short-term memory and reading skills that are carried out to examine the relationship between short-term memory processes and reading comprehension. In this study information coming to short-term memory and the factors affecting operation of short term memory are investigated with regression model. The aim of the research is to examine the factors (age, IQ and reading skills that are expected the have an effect on short-term memory in children through regression analysis. One of the assumptions of regression analysis is to examine which has constant variance and normal distribution of the error term. In this study, because the error term is not normally distributed, robust regression techniques were applied. Also, for each technique; coefficient of determination is determined. According to the findings, the increase in age, IQ and reading skills caused the increase in short term memory in children. After applying robust regression techniques, the Winsorized Least Squares (WLS technique gives the highest coefficient of determination.

  9. Audit of long-term and short-term liabilities

    Directory of Open Access Journals (Sweden)

    Korinko M.D.

    2017-03-01

    Full Text Available The article determines the importance of long-term and short-term liabilities for the management of financial and material resources of an enterprise. It reviews the aim, objects and information generators for realization of audit of short-term and long-term obligations. The organizing and methodical providing of audit of long-term and short-term liabilities of an enterprise are generalized. The authors distinguish the stages of realization of audit of long-term and short-term liabilities, the aim of audit on each of the presented stages, and recommend methodical techniques. It is fixed that it is necessary to conduct the estimation of the systems of internal control and record-keeping of an enterprise by implementation of public accountant procedures for determination of volume and maintenance of selection realization. After estimating the indicated systems, a public accountant determines the methodology for realization of public accountant verification of long-term and short-term liabilities. The analytical procedures that public accountants are expedient to use for realization of audit of short-term and long-term obligations are determined. The authors suggest the classification of the educed defects on the results of the conducted public accountant verification of short-term and long-term obligations.

  10. Semantic and phonological contributions to short-term repetition and long-term cued sentence recall.

    Science.gov (United States)

    Meltzer, Jed A; Rose, Nathan S; Deschamps, Tiffany; Leigh, Rosie C; Panamsky, Lilia; Silberberg, Alexandra; Madani, Noushin; Links, Kira A

    2016-02-01

    The function of verbal short-term memory is supported not only by the phonological loop, but also by semantic resources that may operate on both short and long time scales. Elucidation of the neural underpinnings of these mechanisms requires effective behavioral manipulations that can selectively engage them. We developed a novel cued sentence recall paradigm to assess the effects of two factors on sentence recall accuracy at short-term and long-term stages. Participants initially repeated auditory sentences immediately following a 14-s retention period. After this task was complete, long-term memory for each sentence was probed by a two-word recall cue. The sentences were either concrete (high imageability) or abstract (low imageability), and the initial 14-s retention period was filled with either an undemanding finger-tapping task or a more engaging articulatory suppression task (Exp. 1, counting backward by threes; Exp. 2, repeating a four-syllable nonword). Recall was always better for the concrete sentences. Articulatory suppression reduced accuracy in short-term recall, especially for abstract sentences, but the sentences initially recalled following articulatory suppression were retained better at the subsequent cued-recall test, suggesting that the engagement of semantic mechanisms for short-term retention promoted encoding of the sentence meaning into long-term memory. These results provide a basis for using sentence imageability and subsequent memory performance as probes of semantic engagement in short-term memory for sentences.

  11. Gene regulatory mechanisms in infected fish

    DEFF Research Database (Denmark)

    Schyth, Brian Dall; Hajiabadi, Seyed Amir Hossein Jalali; Kristensen, Lasse Bøgelund Juel

    2011-01-01

    molecules produced by the eukaryotic cell is used to program the RNA Induced Silencing Complex (RISC) for cleavage of specific mRNA transcripts and/or translational repression in the cytoplasm or even chromatin methylation in the nucleus. All processes leading to silencing of the target gene. MicroRNAs (or...... differentiation. Thus the expression of these miRNAs might be steered by different mechanisms in different cell types and have different roles in terms of the genes they target in different cell types. Thus gene regulation and function is better looked upon as a web of interactions. Data from zebrafish studies...

  12. Short-term changes in neck pain, widespread pressure pain sensitivity, and cervical range of motion after the application of trigger point dry needling in patients with acute mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Mejuto-Vázquez, María J; Salom-Moreno, Jaime; Ortega-Santiago, Ricardo; Truyols-Domínguez, Sebastián; Fernández-de-Las-Peñas, César

    2014-04-01

    Randomized clinical trial. To determine the effects of trigger point dry needling (TrPDN) on neck pain, widespread pressure pain sensitivity, and cervical range of motion in patients with acute mechanical neck pain and active trigger points in the upper trapezius muscle. TrPDN seems to be effective for decreasing pain in individuals with upper-quadrant pain syndromes. Potential effects of TrPDN for decreasing pain and sensitization in individuals with acute mechanical neck pain are needed. Methods Seventeen patients (53% female) were randomly assigned to 1 of 2 groups: a single session of TrPDN or no intervention (waiting list). Pressure pain thresholds over the C5-6 zygapophyseal joint, second metacarpal, and tibialis anterior muscle; neck pain intensity; and cervical spine range-of-motion data were collected at baseline (pretreatment) and 10 minutes and 1 week after the intervention by an assessor blinded to the treatment allocation of the patient. Mixed-model analyses of variance were used to examine the effects of treatment on each outcome variable. Patients treated with 1 session of TrPDN experienced greater decreases in neck pain, greater increases in pressure pain threshold, and higher increases in cervical range of motion than those who did not receive an intervention at both 10 minutes and 1 week after the intervention (Ppain intensity and widespread pressure pain sensitivity, and also increase active cervical range of motion, in patients with acute mechanical neck pain. Changes in pain, pressure pain threshold, and cervical range of motion surpassed their respective minimal detectable change values, supporting clinically relevant treatment effects. Level of Evidence Therapy, level 1b-.

  13. Short-term airing by natural ventilation

    DEFF Research Database (Denmark)

    Perino, Marco; Heiselberg, Per

    2009-01-01

    The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates traditio......The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates...... traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates...... that was aimed at developing and validating numerical models for the analysis of buoyancy driven single-sided natural ventilation systems. Once validated, these models can be used to optimize control strategies in order to achieve satisfactory indoor comfort conditions and IAQ....

  14. Auditory short-term memory behaves like visual short-term memory.

    Directory of Open Access Journals (Sweden)

    Kristina M Visscher

    2007-03-01

    Full Text Available Are the information processing steps that support short-term sensory memory common to all the senses? Systematic, psychophysical comparison requires identical experimental paradigms and comparable stimuli, which can be challenging to obtain across modalities. Participants performed a recognition memory task with auditory and visual stimuli that were comparable in complexity and in their neural representations at early stages of cortical processing. The visual stimuli were static and moving Gaussian-windowed, oriented, sinusoidal gratings (Gabor patches; the auditory stimuli were broadband sounds whose frequency content varied sinusoidally over time (moving ripples. Parallel effects on recognition memory were seen for number of items to be remembered, retention interval, and serial position. Further, regardless of modality, predicting an item's recognizability requires taking account of (1 the probe's similarity to the remembered list items (summed similarity, and (2 the similarity between the items in memory (inter-item homogeneity. A model incorporating both these factors gives a good fit to recognition memory data for auditory as well as visual stimuli. In addition, we present the first demonstration of the orthogonality of summed similarity and inter-item homogeneity effects. These data imply that auditory and visual representations undergo very similar transformations while they are encoded and retrieved from memory.

  15. Auditory short-term memory behaves like visual short-term memory.

    Science.gov (United States)

    Visscher, Kristina M; Kaplan, Elina; Kahana, Michael J; Sekuler, Robert

    2007-03-01

    Are the information processing steps that support short-term sensory memory common to all the senses? Systematic, psychophysical comparison requires identical experimental paradigms and comparable stimuli, which can be challenging to obtain across modalities. Participants performed a recognition memory task with auditory and visual stimuli that were comparable in complexity and in their neural representations at early stages of cortical processing. The visual stimuli were static and moving Gaussian-windowed, oriented, sinusoidal gratings (Gabor patches); the auditory stimuli were broadband sounds whose frequency content varied sinusoidally over time (moving ripples). Parallel effects on recognition memory were seen for number of items to be remembered, retention interval, and serial position. Further, regardless of modality, predicting an item's recognizability requires taking account of (1) the probe's similarity to the remembered list items (summed similarity), and (2) the similarity between the items in memory (inter-item homogeneity). A model incorporating both these factors gives a good fit to recognition memory data for auditory as well as visual stimuli. In addition, we present the first demonstration of the orthogonality of summed similarity and inter-item homogeneity effects. These data imply that auditory and visual representations undergo very similar transformations while they are encoded and retrieved from memory.

  16. Short-term effects of simultaneous cardiovascular workout and ...

    African Journals Online (AJOL)

    PMD), has become a growing public health concern, as it may potentially result in the development of hearing difficulties. Objectives: The aim of the study was to determine the differential impact and short-term effects of simultaneous ...

  17. Short-term treatment outcomes of children starting antiretroviral ...

    African Journals Online (AJOL)

    Short-term treatment outcomes of children starting antiretroviral therapy in the intensive care unit, general medical wards and outpatient HIV clinics at Red Cross War Memorial Children's Hospital, Cape Town, South Africa: A retrospective cohort study.

  18. Short-Term Memory in Habituation and Dishabituation

    Science.gov (United States)

    Whitlow, Jesse William, Jr.

    1975-01-01

    The present research evaluated the refractorylike response decrement, as found in habituation of auditory evoked peripheral vasoconstriction in rabbits, to determine whether or not it represents a short-term habituation process distinct from effector fatigue or sensory adaptation. (Editor)

  19. Short-term outcome of patients with closed comminuted femoral ...

    African Journals Online (AJOL)

    Short-term outcome of patients with closed comminuted femoral shaft fracture treated with locking intramedullary sign nail at Muhimbili Orthopaedic Institute in Tanzania. Billy T. Haonga, Felix S. Mrita, Edmundo E. Ndalama, Jackline E. Makupa ...

  20. Short term variations in particulate matter in Mahi river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Rokade, M.A.; Zingde, M.D.

    The particulate matter (PM) collected from Mahi River Estuary was analysed for organic carbon (POC), nitrogen (PON), and chlorophyll a (Chl a). The concentration of PM, POC, PON and Chl a showed short term variations. Average surface concentration...

  1. Short-Term Wind Speed Forecasting for Power System Operations

    KAUST Repository

    Zhu, Xinxin; Genton, Marc G.

    2012-01-01

    some statistical short-term wind speed forecasting models, including traditional time series approaches and more advanced space-time statistical models. It also discusses the evaluation of forecast accuracy, in particular, the need for realistic loss

  2. The nature of forgetting from short-term memory

    OpenAIRE

    Muter, Paul

    2001-01-01

    Memory and forgetting are inextricably intertwined. Any account of short-term memory (STM) should address the following question: If three, four, or five chunks are being held in STM, what happens after attention is diverted?

  3. Parent-Offspring Conflict over Short-Term Mating Strategies

    Directory of Open Access Journals (Sweden)

    Spyroulla Georgiou

    2011-12-01

    Full Text Available Individuals engage in short-term mating strategies that enable them to obtain fitness benefits from casual relationships. These benefits, however, count for less and cost more to their parents. On this basis three hypotheses are tested. First, parents and offspring are likely to disagree over short-term mating strategies, with the former considering these as less acceptable than the latter. Second, parents are more likely to disapprove of the short-term mating strategies of their daughters than of their sons. Finally, mothers and fathers are expected to agree on how much they disagree over the short-term mating strategies of their children. Evidence from a sample of 148 Greek-Cypriot families (140 mothers, 105 fathers, 119 daughters, 77 sons provides support for the first two hypotheses and partial support for the third hypothesis. The implications of these findings for understanding family dynamics are further discussed.

  4. Short-term lending: Payday loans as risk factors for anxiety, inflammation and poor health.

    Science.gov (United States)

    Sweet, Elizabeth; Kuzawa, Christopher W; McDade, Thomas W

    2018-08-01

    While research now consistently links consumer financial debt with adverse emotional health outcomes, specific forms of debt and their impact on measures of physical health are underexplored. This gap in knowledge is significant because different forms of loans and debt may have different experiential qualities. In this paper, we focus on a type of unsecured debt - short-term/payday loan borrowing - that has risen dramatically in recent decades in the United States and is characterized by predatory, discriminatory, and poorly regulated lending practices. Using data from a study of debt and health among adults in Boston, MA (n=286), we test whether short-term borrowing is associated with a range of emotional and physical health indicators. We find that short-term loans are associated with higher body mass index, waist circumference, C-reactive protein levels, and self-reported symptoms of physical health, sexual health, and anxiety, after controlling for several socio-demographic covariates. We discuss these findings within the contexts of regulatory shortcomings, psychosocial stress, and racial and economic credit disparities. We suggest that within the broader context of financial debt and health, short-term loans should be considered a specific risk to population health.

  5. Short-Term Wind Speed Forecasting Using Decomposition-Based Neural Networks Combining Abnormal Detection Method

    Directory of Open Access Journals (Sweden)

    Xuejun Chen

    2014-01-01

    Full Text Available As one of the most promising renewable resources in electricity generation, wind energy is acknowledged for its significant environmental contributions and economic competitiveness. Because wind fluctuates with strong variation, it is quite difficult to describe the characteristics of wind or to estimate the power output that will be injected into the grid. In particular, short-term wind speed forecasting, an essential support for the regulatory actions and short-term load dispatching planning during the operation of wind farms, is currently regarded as one of the most difficult problems to be solved. This paper contributes to short-term wind speed forecasting by developing two three-stage hybrid approaches; both are combinations of the five-three-Hanning (53H weighted average smoothing method, ensemble empirical mode decomposition (EEMD algorithm, and nonlinear autoregressive (NAR neural networks. The chosen datasets are ten-minute wind speed observations, including twelve samples, and our simulation indicates that the proposed methods perform much better than the traditional ones when addressing short-term wind speed forecasting problems.

  6. Short-term Consumer Benefits of Dynamic Pricing

    OpenAIRE

    Dupont, Benjamin; De Jonghe, Cedric; Kessels, Kris; Belmans, Ronnie

    2011-01-01

    Consumer benefits of dynamic pricing depend on a variety of factors. Consumer characteristics and climatic circumstances widely differ, which forces a regional comparison. This paper presents a general overview of demand response programs and focuses on the short-term benefits of dynamic pricing for an average Flemish residential consumer. It reaches a methodology to develop a cost reflective dynamic pricing program and to estimate short-term bill savings. Participating in a dynamic pricing p...

  7. Behavioural Models of Motor Control and Short-Term Memory

    OpenAIRE

    Imanaka, Kuniyasu; Funase, Kozo; Yamauchi, Masaki

    1995-01-01

    We examined in this review article the behavioural and conceptual models of motor control and short-term memory which have intensively been investigated since the 1970s. First, we reviewed both the dual-storage model of short-term memory in which movement information is stored and a typical model of motor control which emphasizes the importance of efferent factors. We then examined two models of preselection effects: a cognitive model and a cognitive/ efferent model. Following this we reviewe...

  8. An ethics curriculum for short-term global health trainees

    OpenAIRE

    DeCamp, Matthew; Rodriguez, Joce; Hecht, Shelby; Barry, Michele; Sugarman, Jeremy

    2013-01-01

    Background Interest in short-term global health training and service programs continues to grow, yet they can be associated with a variety of ethical issues for which trainees or others with limited global health experience may not be prepared to address. Therefore, there is a clear need for educational interventions concerning these ethical issues. Methods We developed and evaluated an introductory curriculum, ?Ethical Challenges in Short-term Global Health Training.? The curriculum was deve...

  9. Short-term incentive schemes for hospital managers

    Directory of Open Access Journals (Sweden)

    Lucas Malambe

    2013-10-01

    Full Text Available Orientation: Short-term incentives, considered to be an extrinsic motivation, are commonly used to motivate performance. This study explored hospital managers’ perceptions of short term incentives in maximising performance and retention. Research purpose: The study explored the experiences, views and perceptions of private hospital managers in South Africa regarding the use of short-term incentives to maximise performance and retention, as well as the applicability of the findings to public hospitals. Motivation for the study: Whilst there is an established link between performance reward schemes and organisational performance, there is little understanding of the effects of short term incentives on the performance and retention of hospital managers within the South African context. Research design, approach, and method: The study used a qualitative research design: interviews were conducted with a purposive sample of 19 hospital managers, and a thematic content analysis was performed. Main findings: Short-term incentives may not be the primary motivator for hospital managers, but they do play a critical role in sustaining motivation. Participants indicated that these schemes could also be applicable to public hospitals. Practical/managerial implications: Hospital managers are inclined to be more motivated by intrinsic than extrinsic factors. However, hospital managers (as middle managers also seem to be motivated by short-term incentives. A combination of intrinsic and extrinsic motivators should thus be used to maximise performance and retention. Contribution/value-add: Whilst the study sought to explore hospital managers’ perceptions of short-term incentives, it also found that an adequate balance between internal and external motivators is key to implementing an effective short-term incentive scheme.

  10. Frequency-specific insight into short-term memory capacity

    OpenAIRE

    Feurra, Matteo; Galli, Giulia; Pavone, Enea Francesco; Rossi, Alessandro; Rossi, Simone

    2016-01-01

    We provided novel evidence of a frequency-specific effect by transcranial alternating current stimulation (tACS) of the left posterior parietal cortex on short-term memory, during a digit span task. the effect was prominent with stimulation at beta frequency for young and not for middle-aged adults and correlated with age. Our findings highlighted a short-term memory capacity improvement by tACS application.

  11. Short-term memory for scenes with affective content

    OpenAIRE

    Maljkovic, Vera; Martini, Paolo

    2005-01-01

    The emotional content of visual images can be parameterized along two dimensions: valence (pleasantness) and arousal (intensity of emotion). In this study we ask how these distinct emotional dimensions affect the short-term memory of human observers viewing a rapid stream of images and trying to remember their content. We show that valence and arousal modulate short-term memory as independent factors. Arousal influences dramatically the average speed of data accumulation in memory: Higher aro...

  12. Narcissism and the Strategic Pursuit of Short-Term Mating

    DEFF Research Database (Denmark)

    Schmitt, David P.; Alcalay, Lidia; Allik, Jüri

    2017-01-01

    Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the curr...... limitations of these cross-culturally universal findings and presents suggestions for future research into revealing the precise psychological features of narcissism that facilitate the strategic pursuit of short-term mating....

  13. Density-dependence as a size-independent regulatory mechanism

    NARCIS (Netherlands)

    De Vladar, H.P.

    2006-01-01

    The growth function of populations is central in biomathematics. The main dogma is the existence of density-dependence mechanisms, which can be modelled with distinct functional forms that depend on the size of the Population. One important class of regulatory functions is the theta-logistic, which

  14. Transcriptome profiling reveals regulatory mechanisms underlying Corolla Senescence in Petunia

    Science.gov (United States)

    Genetic regulatory mechanisms that govern petal natural senescence in petunia is complicated and unclear. To identify key genes and pathways that regulate the process, we initiated a transcriptome analysis in petunia petals at four developmental time points, including petal opening without anthesis ...

  15. Genetic deletion of melanin-concentrating hormone neurons impairs hippocampal short-term synaptic plasticity and hippocampal-dependent forms of short-term memory.

    Science.gov (United States)

    Le Barillier, Léa; Léger, Lucienne; Luppi, Pierre-Hervé; Fort, Patrice; Malleret, Gaël; Salin, Paul-Antoine

    2015-11-01

    The cognitive role of melanin-concentrating hormone (MCH) neurons, a neuronal population located in the mammalian postero-lateral hypothalamus sending projections to all cortical areas, remains poorly understood. Mainly activated during paradoxical sleep (PS), MCH neurons have been implicated in sleep regulation. The genetic deletion of the only known MCH receptor in rodent leads to an impairment of hippocampal dependent forms of memory and to an alteration of hippocampal long-term synaptic plasticity. By using MCH/ataxin3 mice, a genetic model characterized by a selective deletion of MCH neurons in the adult, we investigated the role of MCH neurons in hippocampal synaptic plasticity and hippocampal-dependent forms of memory. MCH/ataxin3 mice exhibited a deficit in the early part of both long-term potentiation and depression in the CA1 area of the hippocampus. Post-tetanic potentiation (PTP) was diminished while synaptic depression induced by repetitive stimulation was enhanced suggesting an alteration of pre-synaptic forms of short-term plasticity in these mice. Behaviorally, MCH/ataxin3 mice spent more time and showed a higher level of hesitation as compared to their controls in performing a short-term memory T-maze task, displayed retardation in acquiring a reference memory task in a Morris water maze, and showed a habituation deficit in an open field task. Deletion of MCH neurons could thus alter spatial short-term memory by impairing short-term plasticity in the hippocampus. Altogether, these findings could provide a cellular mechanism by which PS may facilitate memory encoding. Via MCH neuron activation, PS could prepare the day's learning by increasing and modulating short-term synaptic plasticity in the hippocampus. © 2015 Wiley Periodicals, Inc.

  16. Short term braking capability during power interruptions for integrated matrix converter

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2004-01-01

    attractive. Sinusoidal input currents and bi-directional power flow are other advantages of the matrix converter, but it is less immune to power grid disturbances compared to a standard ASD. In hoisting applications, short-term braking capability during a power outage is needed until the mechanical brake...... engages or to perform more effective a combined braking. This paper proposes a new method to provide short-term braking capability during a power outage for matrix converters. A braking chopper is needed in the clamp circuit, which allows for a drastically reduction of the capacitor size. The power flow...

  17. Short term Braking Capability during Power Interruptions for Integrated Matrix Converter-Motor Drives

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2002-01-01

    attractive. Sinusoidal input currents and bi-directional power flow are other advantages of the matrix converter but it is less immune to power grid disturbances compared to a standard ASD. In hoisting applications, short-term braking capability during a power outage is needed until the mechanical brake...... engages or to perform more effective a combined braking.This paper proposes a new method to provide short-term braking capability during a power outage for matrix converters. A braking chopper is needed in the clamp circuit, which allows for a drastically reduction of the capacitor size. The power flow...

  18. Short-term perceptual learning in visual conjunction search.

    Science.gov (United States)

    Su, Yuling; Lai, Yunpeng; Huang, Wanyi; Tan, Wei; Qu, Zhe; Ding, Yulong

    2014-08-01

    Although some studies showed that training can improve the ability of cross-dimension conjunction search, less is known about the underlying mechanism. Specifically, it remains unclear whether training of visual conjunction search can successfully bind different features of separated dimensions into a new function unit at early stages of visual processing. In the present study, we utilized stimulus specificity and generalization to provide a new approach to investigate the mechanisms underlying perceptual learning (PL) in visual conjunction search. Five experiments consistently showed that after 40 to 50 min of training of color-shape/orientation conjunction search, the ability to search for a certain conjunction target improved significantly and the learning effects did not transfer to a new target that differed from the trained target in both color and shape/orientation features. However, the learning effects were not strictly specific. In color-shape conjunction search, although the learning effect could not transfer to a same-shape different-color target, it almost completely transferred to a same-color different-shape target. In color-orientation conjunction search, the learning effect partly transferred to a new target that shared same color or same orientation with the trained target. Moreover, the sum of transfer effects for the same color target and the same orientation target in color-orientation conjunction search was algebraically equivalent to the learning effect for trained target, showing an additive transfer effect. The different transfer patterns in color-shape and color-orientation conjunction search learning might reflect the different complexity and discriminability between feature dimensions. These results suggested a feature-based attention enhancement mechanism rather than a unitization mechanism underlying the short-term PL of color-shape/orientation conjunction search.

  19. Short-term fasting promotes insulin expression in rat hypothalamus.

    Science.gov (United States)

    Dakic, Tamara B; Jevdjovic, Tanja V; Peric, Mina I; Bjelobaba, Ivana M; Markelic, Milica B; Milutinovic, Bojana S; Lakic, Iva V; Jasnic, Nebojsa I; Djordjevic, Jelena D; Vujovic, Predrag Z

    2017-07-01

    In the hypothalamus, insulin takes on many roles involved in energy homoeostasis. Therefore, the aim of this study was to examine hypothalamic insulin expression during the initial phase of the metabolic response to fasting. Hypothalamic insulin content was assessed by both radioimmunoassay and Western blot. The relative expression of insulin mRNA was examined by qPCR. Immunofluorescence and immunohistochemistry were used to determine the distribution of insulin immunopositivity in the hypothalamus. After 6-h fasting, both glucose and insulin levels were decreased in serum but not in the cerebrospinal fluid. Our study showed for the first time that, while the concentration of circulating glucose and insulin decreased, both insulin mRNA expression and insulin content in the hypothalamic parenchyma were increased after short-term fasting. Increased insulin immunopositivity was detected specifically in the neurons of the hypothalamic periventricular nucleus and in the ependymal cells of fasting animals. These novel findings point to the complexity of mechanisms regulating insulin expression in the CNS in general and in the hypothalamus in particular. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Short-term ionic plasticity at GABAergic synapses

    Directory of Open Access Journals (Sweden)

    Joseph Valentino Raimondo

    2012-10-01

    Full Text Available Fast synaptic inhibition in the brain is mediated by the pre-synaptic release of the neurotransmitter γ-Aminobutyric acid (GABA and the post-synaptic activation of GABA-sensitive ionotropic receptors. As with excitatory synapses, it is being increasinly appreciated that a variety of plastic processes occur at inhibitory synapses, which operate over a range of timescales. Here we examine a form of activity-dependent plasticity that is somewhat unique to GABAergic transmission. This involves short-lasting changes to the ionic driving force for the postsynaptic receptors, a process referred to as short-term ionic plasticity. These changes are directly related to the history of activity at inhibitory synapses and are influenced by a variety of factors including the location of the synapse and the post-synaptic cell’s ion regulation mechanisms. We explore the processes underlying this form of plasticity, when and where it can occur, and how it is likely to impact network activity.

  1. Coherent oscillatory networks supporting short-term memory retention.

    Science.gov (United States)

    Payne, Lisa; Kounios, John

    2009-01-09

    Accumulating evidence suggests that top-down processes, reflected by frontal-midline theta-band (4-8 Hz) electroencephalogram (EEG) oscillations, strengthen the activation of a memory set during short-term memory (STM) retention. In addition, the amplitude of posterior alpha-band (8-13 Hz) oscillations during STM retention is thought to reflect a mechanism that protects fragile STM activations from interference by gating bottom-up sensory inputs. The present study addressed two important questions about these phenomena. First, why have previous studies not consistently found memory set-size effects on frontal-midline theta? Second, how does posterior alpha participate in STM retention? To answer these questions, large-scale network connectivity during STM retention was examined by computing EEG wavelet coherence during the retention period of a modified Sternberg task using visually-presented letters as stimuli. The results showed (a) increasing theta-band coherence between frontal-midline and left temporal-parietal sites with increasing memory load, and (b) increasing alpha-band coherence between midline parietal and left temporal/parietal sites with increasing memory load. These findings support the view that theta-band coherence, rather than amplitude, is the key factor in selective top-down strengthening of the memory set and demonstrate that posterior alpha-band oscillations associated with sensory gating are involved in STM retention by participating in the STM network.

  2. Visual short-term memory load strengthens selective attention.

    Science.gov (United States)

    Roper, Zachary J J; Vecera, Shaun P

    2014-04-01

    Perceptual load theory accounts for many attentional phenomena; however, its mechanism remains elusive because it invokes underspecified attentional resources. Recent dual-task evidence has revealed that a concurrent visual short-term memory (VSTM) load slows visual search and reduces contrast sensitivity, but it is unknown whether a VSTM load also constricts attention in a canonical perceptual load task. If attentional selection draws upon VSTM resources, then distraction effects-which measure attentional "spill-over"-will be reduced as competition for resources increases. Observers performed a low perceptual load flanker task during the delay period of a VSTM change detection task. We observed a reduction of the flanker effect in the perceptual load task as a function of increasing concurrent VSTM load. These findings were not due to perceptual-level interactions between the physical displays of the two tasks. Our findings suggest that perceptual representations of distractor stimuli compete with the maintenance of visual representations held in memory. We conclude that access to VSTM determines the degree of attentional selectivity; when VSTM is not completely taxed, it is more likely for task-irrelevant items to be consolidated and, consequently, affect responses. The "resources" hypothesized by load theory are at least partly mnemonic in nature, due to the strong correspondence they share with VSTM capacity.

  3. Monkeys Rely on Recency of Stimulus Repetition When Solving Short-Term Memory Tasks

    Science.gov (United States)

    Wittig, John H., Jr.; Richmond, Barry J.

    2014-01-01

    Seven monkeys performed variants of two short-term memory tasks that others have used to differentiate between selective and nonselective memory mechanisms. The first task was to view a list of sequentially presented images and identify whether a test matched any image from the list, but not a distractor from a preceding list. Performance was best…

  4. Short-Term Memory for Serial Order: A Recurrent Neural Network Model

    Science.gov (United States)

    Botvinick, Matthew M.; Plaut, David C.

    2006-01-01

    Despite a century of research, the mechanisms underlying short-term or working memory for serial order remain uncertain. Recent theoretical models have converged on a particular account, based on transient associations between independent item and context representations. In the present article, the authors present an alternative model, according…

  5. Short-term stress enhances cellular immunity and increases early resistance to squamous cell carcinoma.

    Science.gov (United States)

    Dhabhar, Firdaus S; Saul, Alison N; Daugherty, Christine; Holmes, Tyson H; Bouley, Donna M; Oberyszyn, Tatiana M

    2010-01-01

    In contrast to chronic/long-term stress that suppresses/dysregulates immune function, an acute/short-term fight-or-flight stress response experienced during immune activation can enhance innate and adaptive immunity. Moderate ultraviolet-B (UV) exposure provides a non-invasive system for studying the naturalistic emergence, progression and regression of squamous cell carcinoma (SCC). Because SCC is an immunoresponsive cancer, we hypothesized that short-term stress experienced before UV exposure would enhance protective immunity and increase resistance to SCC. Control and short-term stress groups were treated identically except that the short-term stress group was restrained (2.5h) before each of nine UV-exposure sessions (minimum erythemal dose, 3-times/week) during weeks 4-6 of the 10-week UV exposure protocol. Tumors were measured weekly, and tissue collected at weeks 7, 20, and 32. Chemokine and cytokine gene expression was quantified by real-time PCR, and CD4+ and CD8+ T cells by flow cytometry and immunohistochemistry. Compared to controls, the short-term stress group showed greater cutaneous T-cell attracting chemokine (CTACK)/CCL27, RANTES, IL-12, and IFN-gamma gene expression at weeks 7, 20, and 32, higher skin infiltrating T cell numbers (weeks 7 and 20), lower tumor incidence (weeks 11-20) and fewer tumors (weeks 11-26). These results suggest that activation of short-term stress physiology increased chemokine expression and T cell trafficking and/or function during/following UV exposure, and enhanced Type 1 cytokine-driven cell-mediated immunity that is crucial for resistance to SCC. Therefore, the physiological fight-or-flight stress response and its adjuvant-like immuno-enhancing effects, may provide a novel and important mechanism for enhancing immune system mediated tumor-detection/elimination that merits further investigation.

  6. Impaired short-term memory for pitch in congenital amusia.

    Science.gov (United States)

    Tillmann, Barbara; Lévêque, Yohana; Fornoni, Lesly; Albouy, Philippe; Caclin, Anne

    2016-06-01

    Congenital amusia is a neuro-developmental disorder of music perception and production. The hypothesis is that the musical deficits arise from altered pitch processing, with impairments in pitch discrimination (i.e., pitch change detection, pitch direction discrimination and identification) and short-term memory. The present review article focuses on the deficit of short-term memory for pitch. Overall, the data discussed here suggest impairments at each level of processing in short-term memory tasks; starting with the encoding of the pitch information and the creation of the adequate memory trace, the retention of the pitch traces over time as well as the recollection and comparison of the stored information with newly incoming information. These impairments have been related to altered brain responses in a distributed fronto-temporal network, associated with decreased connectivity between these structures, as well as in abnormalities in the connectivity between the two auditory cortices. In contrast, amusic participants׳ short-term memory abilities for verbal material are preserved. These findings show that short-term memory deficits in congenital amusia are specific to pitch, suggesting a pitch-memory system that is, at least partly, separated from verbal memory. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Circadian modulation of short-term memory in Drosophila.

    Science.gov (United States)

    Lyons, Lisa C; Roman, Gregg

    2009-01-01

    Endogenous biological clocks are widespread regulators of behavior and physiology, allowing for a more efficient allocation of efforts and resources over the course of a day. The extent that different processes are regulated by circadian oscillators, however, is not fully understood. We investigated the role of the circadian clock on short-term associative memory formation using a negatively reinforced olfactory-learning paradigm in Drosophila melanogaster. We found that memory formation was regulated in a circadian manner. The peak performance in short-term memory (STM) occurred during the early subjective night with a twofold performance amplitude after a single pairing of conditioned and unconditioned stimuli. This rhythm in memory is eliminated in both timeless and period mutants and is absent during constant light conditions. Circadian gating of sensory perception does not appear to underlie the rhythm in short-term memory as evidenced by the nonrhythmic shock avoidance and olfactory avoidance behaviors. Moreover, central brain oscillators appear to be responsible for the modulation as cryptochrome mutants, in which the antennal circadian oscillators are nonfunctional, demonstrate robust circadian rhythms in short-term memory. Together these data suggest that central, rather than peripheral, circadian oscillators modulate the formation of short-term associative memory and not the perception of the stimuli.

  8. LANGUAGE REPETITION AND SHORT-TERM MEMORY: AN INTEGRATIVE FRAMEWORK

    Directory of Open Access Journals (Sweden)

    Steve eMajerus

    2013-07-01

    Full Text Available Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the nonword-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

  9. Language repetition and short-term memory: an integrative framework.

    Science.gov (United States)

    Majerus, Steve

    2013-01-01

    Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the non-word-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

  10. Short-term and working memory impairments in aphasia.

    Science.gov (United States)

    Potagas, Constantin; Kasselimis, Dimitrios; Evdokimidis, Ioannis

    2011-08-01

    The aim of the present study is to investigate short-term memory and working memory deficits in aphasics in relation to the severity of their language impairment. Fifty-eight aphasic patients participated in this study. Based on language assessment, an aphasia score was calculated for each patient. Memory was assessed in two modalities, verbal and spatial. Mean scores for all memory tasks were lower than normal. Aphasia score was significantly correlated with performance on all memory tasks. Correlation coefficients for short-term memory and working memory were approximately of the same magnitude. According to our findings, severity of aphasia is related with both verbal and spatial memory deficits. Moreover, while aphasia score correlated with lower scores in both short-term memory and working memory tasks, the lack of substantial difference between corresponding correlation coefficients suggests a possible primary deficit in information retention rather than impairment in working memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. The pedagogy of Short-Term Study-Abroad Programs

    Directory of Open Access Journals (Sweden)

    Jude Gonsalvez

    2013-10-01

    Full Text Available This paper focuses on establishing guidelines on the pedagogy of short term study abroad programs. This study follows 33 students who participated in a short-term study-abroad program to India with the researcher from 2006 through 2011. The study relies heavily on the student reflections and expressions as they experienced them. It is qualitative in nature. Focus groups were the main method of data collection, where participants were invited to reflect, express, and share their experiences with one another. This provided an opportunity for the participants to come together, relive their experiences, and help provide information as to how and what type of an influence this short-term study-abroad program provided.

  12. Model documentation report: Short-Term Hydroelectric Generation Model

    International Nuclear Information System (INIS)

    1993-08-01

    The purpose of this report is to define the objectives of the Short- Term Hydroelectric Generation Model (STHGM), describe its basic approach, and to provide details on the model structure. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with the Energy Information Administration's (AYE) legal obligation to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). The STHGM performs a short-term (18 to 27- month) forecast of hydroelectric generation in the United States using an autoregressive integrated moving average (UREMIA) time series model with precipitation as an explanatory variable. The model results are used as input for the short-term Energy Outlook

  13. Verbal short-term memory and vocabulary learning in polyglots.

    Science.gov (United States)

    Papagno, C; Vallar, G

    1995-02-01

    Polyglot and non-polyglot Italian subjects were given tests assessing verbal (phonological) and visuo-spatial short-term and long-term memory, general intelligence, and vocabulary knowledge in their native language. Polyglots had a superior level of performance in verbal short-term memory tasks (auditory digit span and nonword repetition) and in a paired-associate learning test, which assessed the subjects' ability to acquire new (Russian) words. By contrast, the two groups had comparable performance levels in tasks assessing general intelligence, visuo-spatial short-term memory and learning, and paired-associate learning of Italian words. These findings, which are in line with neuropsychological and developmental evidence, as well as with data from normal subjects, suggest a close relationship between the capacity of phonological memory and the acquisition of foreign languages.

  14. [Neuronal and hormonal regulatory mechanisms of tears production and secretion].

    Science.gov (United States)

    Mrugacz, Małgorzata; Zywalewska, Nella; Bakunowicz-Lazarczyk, Alina

    2005-01-01

    The ocular surface, tear film, lacrimal glands act as a functional unit to preserve the quality of the refractive surface of the eye, and to resist injury and protect the eye against bodily and environmental conditions. Homeostasis of this functional unit involves neuronal and hormonal regulatory mechanisms. The eye appears to be a target organ for sex hormones particulary the androgen, as they modulate the immune system and trophic functions of the lacrimal and Meibomian glands.

  15. A new ensemble model for short term wind power prediction

    DEFF Research Database (Denmark)

    Madsen, Henrik; Albu, Razvan-Daniel; Felea, Ioan

    2012-01-01

    As the objective of this study, a non-linear ensemble system is used to develop a new model for predicting wind speed in short-term time scale. Short-term wind power prediction becomes an extremely important field of research for the energy sector. Regardless of the recent advancements in the re-search...... of prediction models, it was observed that different models have different capabilities and also no single model is suitable under all situations. The idea behind EPS (ensemble prediction systems) is to take advantage of the unique features of each subsystem to detain diverse patterns that exist in the dataset...

  16. [Impulsiveness Among Short-Term Prisoners with Antisocial Personality Disorder].

    Science.gov (United States)

    Lang, Fabian U; Otte, Stefanie; Vasic, Nenad; Jäger, Markus; Dudeck, Manuela

    2015-07-01

    The study aimed to investigate the correlation between impulsiveness and the antisocial personality disorder among short-term prisoners. The impulsiveness was diagnosed by the Barratt Impulsiveness Scale (BIS). Short-term prisoners with antisocial personality disorder scored significant higher marks on the BIS total scale than those without any personality disorder. In detail, they scored higher marks on each subscale regarding attentional, motor and nonplanning impulsiveness. Moderate and high effects were calculated. It is to be considered to regard impulsivity as a conceptual component of antisociality. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Predicting short-term stock fluctuations by using processing fluency

    Science.gov (United States)

    Alter, Adam L.; Oppenheimer, Daniel M.

    2006-01-01

    Three studies investigated the impact of the psychological principle of fluency (that people tend to prefer easily processed information) on short-term share price movements. In both a laboratory study and two analyses of naturalistic real-world stock market data, fluently named stocks robustly outperformed stocks with disfluent names in the short term. For example, in one study, an initial investment of $1,000 yielded a profit of $112 more after 1 day of trading for a basket of fluently named shares than for a basket of disfluently named shares. These results imply that simple, cognitive approaches to modeling human behavior sometimes outperform more typical, complex alternatives. PMID:16754871

  18. Short-term memory binding deficits in Alzheimer's disease

    OpenAIRE

    Parra, Mario; Abrahams, S.; Fabi, K.; Logie, R.; Luzzi, S.; Della Sala, Sergio

    2009-01-01

    Alzheimer's disease impairs long term memories for related events (e.g. faces with names) more than for single events (e.g. list of faces or names). Whether or not this associative or ‘binding’ deficit is also found in short-term memory has not yet been explored. In two experiments we investigated binding deficits in verbal short-term memory in Alzheimer's disease. Experiment 1 : 23 patients with Alzheimer's disease and 23 age and education matched healthy elderly were recruited. Participants...

  19. Conceptual short term memory in perception and thought.

    Science.gov (United States)

    Potter, Mary C

    2012-01-01

    Conceptual short term memory (CSTM) is a theoretical construct that provides one answer to the question of how perceptual and conceptual processes are related. CSTM is a mental buffer and processor in which current perceptual stimuli and their associated concepts from long term memory (LTM) are represented briefly, allowing meaningful patterns or structures to be identified (Potter, 1993, 1999, 2009). CSTM is different from and complementary to other proposed forms of working memory: it is engaged extremely rapidly, has a large but ill-defined capacity, is largely unconscious, and is the basis for the unreflective understanding that is characteristic of everyday experience. The key idea behind CSTM is that most cognitive processing occurs without review or rehearsal of material in standard working memory and with little or no conscious reasoning. When one perceives a meaningful stimulus such as a word, picture, or object, it is rapidly identified at a conceptual level and in turn activates associated information from LTM. New links among concurrently active concepts are formed in CSTM, shaped by parsing mechanisms of language or grouping principles in scene perception and by higher-level knowledge and current goals. The resulting structure represents the gist of a picture or the meaning of a sentence, and it is this structure that we are conscious of and that can be maintained in standard working memory and consolidated into LTM. Momentarily activated information that is not incorporated into such structures either never becomes conscious or is rapidly forgotten. This whole cycle - identification of perceptual stimuli, memory recruitment, structuring, consolidation in LTM, and forgetting of non-structured material - may occur in less than 1 s when viewing a pictured scene or reading a sentence. The evidence for such a process is reviewed and its implications for the relation of perception and cognition are discussed.

  20. Conceptual Short Term Memory in perception and thought

    Directory of Open Access Journals (Sweden)

    Mary C. Potter

    2012-04-01

    Full Text Available Conceptual short term memory (CSTM is a theoretical construct that provides one answer to the question of how perceptual and conceptual processes are related. CSTM is a mental buffer and processor in which current perceptual stimuli and their associated concepts from long term memory (LTM are represented briefly, allowing meaningful patterns or structures to be identified (Potter, 1993, 1999, 2009. CSTM is different from and complementary to other proposed forms of working memory: it is engaged extremely rapidly, has a large but ill-defined capacity, is largely unconscious, and is the basis for the unreflective understanding that is characteristic of everyday experience. The key idea behind CSTM is that most cognitive processing occurs without review or rehearsal of material in standard working memory and with little or no conscious reasoning. When one perceives a meaningful stimulus such as a word, picture, or object, it is rapidly identified at a conceptual level and in turn activates associated information from long term memory. New links among concurrently active concepts are formed in CSTM, shaped by parsing mechanisms of language or grouping principles in scene perception and by higher-level knowledge and current goals. The resulting structure represents the gist of a picture or the meaning of a sentence, and it is this structure that we are conscious of and that can be maintained in standard working memory and consolidated into long term memory. Momentarily activated information that is not incorporated into such structures either never becomes conscious or is rapidly forgotten. This whole cycle--identification of perceptual stimuli, memory recruitment, structuring, consolidation in long term memory, and forgetting of nonstructured material--may occur in less than 1 second when viewing a pictured scene or reading a sentence. The evidence for such a process is reviewed and its implications for the relation of perception and cognition are

  1. Implementing a short-term loyalty program : case: Bosch Lawn & Garden and the Ventum short-term loyalty program

    OpenAIRE

    Logvinova, Veronika

    2015-01-01

    In 2015, one of the Bosch Home and Garden divisions, Bosch Lawn and Garden, has made a strategic decision to adopt a points-based short-term loyalty program called Ventum LG in the German supermarkets and petrol stations. It was decided that the base of this program will be completed Ventum PT short-term loyalty program which was managed by another division, Bosch Power Tools, and proved to be successful. This thesis aims to evaluate the worthiness of the Ventum LG loyalty program for Bosch L...

  2. Real-time energy resources scheduling considering short-term and very short-term wind forecast

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marco; Sousa, Tiago; Morais, Hugo; Vale, Zita [Polytechnic of Porto (Portugal). GECAD - Knowledge Engineering and Decision Support Research Center

    2012-07-01

    This paper proposes an energy resources management methodology based on three distinct time horizons: day-ahead scheduling, hour-ahead scheduling, and real-time scheduling. In each scheduling process the update of generation and consumption operation and of the storage and electric vehicles storage status are used. Besides the new operation conditions, the most accurate forecast values of wind generation and of consumption using results of short-term and very short-term methods are used. A case study considering a distribution network with intensive use of distributed generation and electric vehicles is presented. (orig.)

  3. Short-Term Effects of Playing Computer Games on Attention

    Science.gov (United States)

    Tahiroglu, Aysegul Yolga; Celik, Gonca Gul; Avci, Ayse; Seydaoglu, Gulsah; Uzel, Mehtap; Altunbas, Handan

    2010-01-01

    Objective: The main aim of the present study is to investigate the short-term cognitive effects of computer games in children with different psychiatric disorders and normal controls. Method: One hundred one children are recruited for the study (aged between 9 and 12 years). All participants played a motor-racing game on the computer for 1 hour.…

  4. The Precategorical Nature of Visual Short-Term Memory

    Science.gov (United States)

    Quinlan, Philip T.; Cohen, Dale J.

    2016-01-01

    We conducted a series of recognition experiments that assessed whether visual short-term memory (VSTM) is sensitive to shared category membership of to-be-remembered (tbr) images of common objects. In Experiment 1 some of the tbr items shared the same basic level category (e.g., hand axe): Such items were no better retained than others. In the…

  5. Pigeon visual short-term memory directly compared to primates.

    Science.gov (United States)

    Wright, Anthony A; Elmore, L Caitlin

    2016-02-01

    Three pigeons were trained to remember arrays of 2-6 colored squares and detect which of two squares had changed color to test their visual short-term memory. Procedures (e.g., stimuli, displays, viewing times, delays) were similar to those used to test monkeys and humans. Following extensive training, pigeons performed slightly better than similarly trained monkeys, but both animal species were considerably less accurate than humans with the same array sizes (2, 4 and 6 items). Pigeons and monkeys showed calculated memory capacities of one item or less, whereas humans showed a memory capacity of 2.5 items. Despite the differences in calculated memory capacities, the pigeons' memory results, like those from monkeys and humans, were all well characterized by an inverse power-law function fit to d' values for the five display sizes. This characterization provides a simple, straightforward summary of the fundamental processing of visual short-term memory (how visual short-term memory declines with memory load) that emphasizes species similarities based upon similar functional relationships. By closely matching pigeon testing parameters to those of monkeys and humans, these similar functional relationships suggest similar underlying processes of visual short-term memory in pigeons, monkeys and humans. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. SHORT-TERM MEMORY IS INDEPENDENT OF BRAIN PROTEIN SYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Hasker P.; Rosenzweig, Mark R.; Jones, Oliver W.

    1980-09-01

    Male Swiss albino CD-1 mice given a single injection of a cerebral protein synthesis inhibitor, anisomycin (ANI) (1 mg/animal), 20 min prior to single trial passive avoidance training demonstrated impaired retention at tests given 3 hr, 6 hr, 1 day, and 7 days after training. Retention was not significantly different from saline controls when tests were given 0.5 or 1.5 hr after training. Prolonging inhibition of brain protein synthesis by giving either 1 or 2 additional injections of ANI 2 or 2 and 4 hr after training did not prolong short-term retention performance. The temporal development of impaired retention in ANI treated mice could not be accounted for by drug dosage, duration of protein synthesis inhibition, or nonspecific sickness at test. In contrast to the suggestion that protein synthesis inhibition prolongs short-term memory (Quinton, 1978), the results of this experiment indicate that short-term memory is not prolonged by antibiotic drugs that inhibit cerebral protein synthesis. All evidence seems consistent with the hypothesis that short-term memory is protein synthesis independent and that the establishment of long-term memory depends upon protein synthesis during or shortly after training. Evidence for a role of protein synthesis in memory maintenance is discussed.

  7. Short-term robustness of production management systems

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; Gaury, E.G.A.

    1998-01-01

    Short-term performance of a production management system for make-to-stock factories may be quantified through the service rate per shift; long-term performance through the average monthly work in process (WIP). This may yield, for example, that WIP is minimized, while the probability of the service

  8. 22 CFR 62.21 - Short-term scholars.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Short-term scholars. 62.21 Section 62.21 Foreign Relations DEPARTMENT OF STATE PUBLIC DIPLOMACY AND EXCHANGES EXCHANGE VISITOR PROGRAM Specific... programs, confer on common problems and projects, and promote professional relationships and communications...

  9. Short-term energy outlook annual supplement, 1993

    International Nuclear Information System (INIS)

    1993-01-01

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the third quarter of 1993 through the fourth quarter of 1994. Values for the second quarter of 1993, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data are EIA data published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding

  10. Short-term feeding strategies and pork quality

    NARCIS (Netherlands)

    Geesink, G.H.; Buren, van R.G.C.; Savenije, B.; Verstegen, M.W.A.; Ducro, B.J.; Palen, van der J.G.P.; Hemke, G.

    2004-01-01

    Two experiments were done to determine whether short-term supplementation (5 days pre-slaughter) with magnesium acetate, or a combination of magnesium acetate, tryptophan, vitamin E and vitamin C would improve pork quality. In the first experiment the pigs (Pietrain x Yorkshire, n = 96) were fed a

  11. Decay uncovered in nonverbal short-term memory.

    Science.gov (United States)

    Mercer, Tom; McKeown, Denis

    2014-02-01

    Decay theory posits that memory traces gradually fade away over the passage of time unless they are actively rehearsed. Much recent work exploring verbal short-term memory has challenged this theory, but there does appear to be evidence for trace decay in nonverbal auditory short-term memory. Numerous discrimination studies have reported a performance decline as the interval separating two tones is increased, consistent with a decay process. However, most of this tone comparison research can be explained in other ways, without reference to decay, and these alternative accounts were tested in the present study. In Experiment 1, signals were employed toward the end of extended retention intervals to ensure that listeners were alert to the presence and frequency content of the memoranda. In Experiment 2, a mask stimulus was employed in an attempt to distinguish between a highly detailed sensory trace and a longer-lasting short-term memory, and the distinctiveness of the stimuli was varied. Despite these precautions, slow-acting trace decay was observed. It therefore appears that the mere passage of time can lead to forgetting in some forms of short-term memory.

  12. Managing Transit Ridership with Short-Term Economic Incentives

    Science.gov (United States)

    1982-08-01

    It is the purpose of this booklet to give the reader an overview of the variety, : type, and nature of short-term economic incentive programs that have been : introduced by transit properties over the past few years. 3054k, 55p.

  13. Short-Term Memory, Executive Control, and Children's Route Learning

    Science.gov (United States)

    Purser, Harry R. M.; Farran, Emily K.; Courbois, Yannick; Lemahieu, Axelle; Mellier, Daniel; Sockeel, Pascal; Blades, Mark

    2012-01-01

    The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11 years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and…

  14. Stacking Ensemble Learning for Short-Term Electricity Consumption Forecasting

    Directory of Open Access Journals (Sweden)

    Federico Divina

    2018-04-01

    Full Text Available The ability to predict short-term electric energy demand would provide several benefits, both at the economic and environmental level. For example, it would allow for an efficient use of resources in order to face the actual demand, reducing the costs associated to the production as well as the emission of CO 2 . To this aim, in this paper we propose a strategy based on ensemble learning in order to tackle the short-term load forecasting problem. In particular, our approach is based on a stacking ensemble learning scheme, where the predictions produced by three base learning methods are used by a top level method in order to produce final predictions. We tested the proposed scheme on a dataset reporting the energy consumption in Spain over more than nine years. The obtained experimental results show that an approach for short-term electricity consumption forecasting based on ensemble learning can help in combining predictions produced by weaker learning methods in order to obtain superior results. In particular, the system produces a lower error with respect to the existing state-of-the art techniques used on the same dataset. More importantly, this case study has shown that using an ensemble scheme can achieve very accurate predictions, and thus that it is a suitable approach for addressing the short-term load forecasting problem.

  15. Short-term outcomes following laparoscopic resection for colon cancer.

    LENUS (Irish Health Repository)

    Kavanagh, Dara O

    2011-03-01

    Laparoscopic resection for colon cancer has been proven to have a similar oncological efficacy compared to open resection. Despite this, it is performed by a minority of colorectal surgeons. The aim of our study was to evaluate the short-term clinical, oncological and survival outcomes in all patients undergoing laparoscopic resection for colon cancer.

  16. Scalable data-driven short-term traffic prediction

    NARCIS (Netherlands)

    Friso, K.; Wismans, L. J.J.; Tijink, M. B.

    2017-01-01

    Short-term traffic prediction has a lot of potential for traffic management. However, most research has traditionally focused on either traffic models-which do not scale very well to large networks, computationally-or on data-driven methods for freeways, leaving out urban arterials completely. Urban

  17. Labeling, Rehearsal, and Short-Term Memory in Retarded Children

    Science.gov (United States)

    Hagen, John W.; And Others

    1974-01-01

    A short-term memory task was used to explore the effects of verbal labeling and rehearsal on serial-position recall in mildly retarded 9-to 11-year-old children. Results support the view that verbal skills affect recall in mildly retarded children similarly to normal children. (Author/SDH)

  18. Short-Term Energy Outlook: Quarterly projections. Fourth quarter 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-05

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the fourth quarter of 1993 through the fourth quarter of 1994. Values for the third quarter of 1993, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data are EIA data published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications.

  19. Short-term variations of radiocarbon during the last century

    International Nuclear Information System (INIS)

    Burchuladze, A.A.; Pagava, S.V.; Jurina, V.; Povinec, P.; Usacev, S.

    1982-01-01

    Radiocarbon variations related to the 11-year solar cycle during the last century are discussed. Previous investigations on short term 14 C variations in tree rings are compared with 14 C measurements in Georgian wine samples. The amplitude of 14 C variations as obtained by various authors ranges from 0.2 to about 1%. (author)

  20. Proactive Interference in Short-Term Recognition and Recall Memory

    Science.gov (United States)

    Dillon, Richard F.; Petrusic, William M.

    1972-01-01

    Purpose of study was to (a) compare the rate of increase of proactive interference over the first few trials under recall and recognition memory test conditions, (2) determine the effects of two types of distractors on short-term recognition, and (3) test memory after proactive interference had reached a stable level under each of three test…

  1. Short-Term Effects of Televised Aggression on Children's Behavior.

    Science.gov (United States)

    Liebert, Robert M.; Baron, Robert A.

    Recently collected data appear to warrant advancing some tentative conslusions concerning the short-term effects of violence in television on children: 1) children are exposed to a substantial amount of violent content on television, and they can remember and learn from such exposure; 2) correlational studies have disclosed a regular association…

  2. Short term clinical outcome of children with rotavirus infection at ...

    African Journals Online (AJOL)

    Background: Rotavirus infection is the single most common cause of acute gastroenteritis in children under five years of age. Rotavirus gastroenteritis has a high morbidity and mortality in children in Kenya. Objectives: To determine the short term clinical outcome for children admitted to Kenyatta National Hospital with ...

  3. Short-term effects of radiation in gliolalstoma spheroids

    DEFF Research Database (Denmark)

    Petterson, Stine Asferg; Jakobsen, Ida Pind; Jensen, Stine Skov

    2016-01-01

    was to investigate the short-term effects of radiation of spheroids containing tumor-initiating stem-like cells. We used a patient-derived glioblastoma stem cell enriched culture (T76) and the standard glioblastoma cell line U87. Primary spheroids were irradiated with doses between 2 and 50 Gy and assessed after two...

  4. Panorama 2012 - Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2011-12-01

    Against the background of an energy market beset by the Fukushima crisis, the Arab spring and economic uncertainty, 2011 saw dynamic growth in demand for natural gas, although developments varied widely from region to region. New trends are emerging in the gas market, and these will have both short-term and longer-term impacts on how the industry develops. (author)

  5. Insulin Resistance Induced by Short term Fructose Feeding may not ...

    African Journals Online (AJOL)

    Fructose feeding causes insulin resistance and invariably Non-Insulin Dependent Diabetes Mellitus (NIDDM) in rats and genetically predisposed humans. The effect of insulin resistance induced by short term fructose feeding on fertility in female rats was investigated using the following parameters: oestrous phase and ...

  6. Histopathologic characteristics and short-term outcomes of ...

    African Journals Online (AJOL)

    Introduction: Colorectal carcinoma (CRC) is generally a disease of persons older than 40 years. Concerning younger patients, controversies still exist regarding features and prognosis of CRC. We performed this study to characterise CRC in young patients (≤40 years) as well as to evaluate short-term outcome in ...

  7. Short-term energy outlook: Quarterly projections, Third quarter 1992

    International Nuclear Information System (INIS)

    1992-08-01

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The principal users of the Outlook are managers and energy analysts in private industry and government. The forecast period for this issue of the Outlook extends from the third quarter of 1992 through the fourth quarter of 1993. Values for the second quarter of 1992, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data are EIA data published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding

  8. Panorama 2013 - Short term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2012-10-01

    The outlook for gas industry development in the short term is clouded by uncertainties (impact of the economic slowdown, competition between energies, price fluctuations, etc.). However, as in 2012, many favorable factors in terms of natural gas supply and demand point to sustained and sustainable growth of this energy. (author)

  9. Orienting attention to objects in visual short-term memory

    NARCIS (Netherlands)

    Dell'Acqua, Roberto; Sessa, Paola; Toffanin, Paolo; Luria, Roy; Joliccoeur, Pierre

    We measured electroencephalographic activity during visual search of a target object among objects available to perception or among objects held in visual short-term memory (VSTM). For perceptual search, a single shape was shown first (pre-cue) followed by a search-array and the task was to decide

  10. SHORT-TERM EFFECT OF DIESEL OIL ON PHYTOPLANKTON

    African Journals Online (AJOL)

    PROF. EKWEME

    Short-term effect of Nigerian diesel oil was tested on the phytoplankton species in Great Kwa River ... aquatic environment. Plant life is the basis of all food web in nature and hence constitutes the makes this fundamental contribution by photosynthesis, utilizing radiant energy to .... (2 cells/ml) re-colonized the area. The three ...

  11. Are there multiple visual short-term memory stores?

    NARCIS (Netherlands)

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

    2008-01-01

    Background: Classic work on visual short-term memory (VSTM) suggests that people store a limited amount of items for subsequent report. However, when human observers are cued to shift attention to one item in VSTM during retention, it seems as if there is a much larger representation, which keeps

  12. Short Term Group Counseling of Visually Impaired People by Telephone.

    Science.gov (United States)

    Jaureguy, Beth M.; Evans, Ron L.

    1983-01-01

    Short term group counseling via the telephone resulted in marked increases in activities of daily living among 12 legally blind veterans. Many subjects' personal coping goals were met as well, and social involvement also increased. No significant changes in levels of depression or agitation were noted. (CL)

  13. Relationship between short-term sexual strategies and sexual jealousy.

    Science.gov (United States)

    Mathes, Eugene W

    2005-02-01

    In a classic study, Buss, Larson, Westen, and Semmelroth reported that men were more distressed by the thought of a partner's sexual infidelity (sexual jealousy) and women were more distressed by the thought of a partner's emotional infidelity (emotional jealousy). Initially, Buss and his associates explained these results by suggesting that men are concerned about uncertainty of paternity, that is, the possibility of raising another man's child while believing the child is their own. However, later they explained the results in terms of men's preference for short-term sexual strategies. The purpose of this research was to test the explanation of short-term sexual strategies. Men and women subjects were instructed to imagine themselves in a relationship which was either short-term (primarily sexual) or long-term (involving commitment) and then respond to Buss's jealousy items. It was hypothesized that, when both men and women imagined a short-term relationship, they would be more threatened by a partner's sexual infidelity, and, when they imagined a long-term relationship, they would be more threatened by a partner's emotional infidelity. Support was found for this hypothesis.

  14. High-intensity exercise and recovery during short-term ...

    African Journals Online (AJOL)

    Objective. To determine the effect of short-term creatine supplementation plus a protein-carbohydrate formula on high-intensity exercise performance and recovery. Design. A repeated-measures, experimental study, employing a randomised, double-blind, placebo-controlled, group comparison design was used.

  15. Can Metabolic Factors be used Prognostically for Short.Term ...

    African Journals Online (AJOL)

    to be promising short.term mortality markers in HIV patients apart from established factors like low CD4 counts, co.morbid conditions, and opportunistic infections like M. tuberculosis infection. This study warrants further studies with a larger sample size to establish HDL and triglyceride as markers of disease progression and ...

  16. Short-term Treatment of Daumone Improves Hepatic Inflammation in Aged Mice.

    Science.gov (United States)

    Park, Jong Hee; Ha, Hunjoo

    2015-05-01

    Chronic inflammation has been proposed as one of the main molecular mechanisms of aging and age-related diseases. Although evidence in humans is limited, short-term calorie restriction (CR) has been shown to have anti-inflammatory effects in aged experimental animals. We reported on the long-term treatment of daumone, a synthetic pheromone secreted by Caenorhabditis elegans in an energy deficient environment, extends the life-span and attenuates liver injury in aged mice. The present study examined whether late onset short-term treatment of daumone exerts anti-inflammatory effects in the livers of aged mice. Daumone was administered orally at doses of 2 or 20 mg/kg/day for 5 weeks to 24-month-old male C57BL/6J mice. Increased liver macrophage infiltration and gene expression of proinflammatory cytokines in aged mice were significantly attenuated by daumone treatment, suggesting that short-term oral administration of daumone may have hepatoprotective effects. Daumone also dose-dependently suppressed tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB (NF-κB) phosphorylation in HepG2 cells. The present data demonstrated that short-term treatment of daumone has anti-inflammatory effects in aged mouse livers possibly through suppression of NF-κB signaling and suggest that daumone may become a lead compound targeting aging and age-associated diseases.

  17. A comparison of short-term dispersion estimates resulting from various atmospheric stability classification methods

    International Nuclear Information System (INIS)

    Mitchell, A.E. Jr.

    1982-01-01

    Four methods of classifying atmospheric stability class are applied at four sites to make short-term (1-h) dispersion estimates from a ground-level source based on a model consistent with U.S. Nuclear Regulatory Commission practice. The classification methods include vertical temperature gradient, standard deviation of horizontal wind direction fluctuations (sigma theta), Pasquill-Turner, and modified sigma theta which accounts for meander. Results indicate that modified sigma theta yields reasonable dispersion estimates compared to those produced using methods of vertical temperature gradient and Pasquill-Turner, and can be considered as a potential economic alternative in establishing onsite monitoring programs. (author)

  18. Ordered Short-Term Memory Differs in Signers and Speakers: Implications for Models of Short-Term Memory

    Science.gov (United States)

    Bavelier, Daphne; Newport, Elissa L.; Hall, Matt; Supalla, Ted; Boutla, Mrim

    2008-01-01

    Capacity limits in linguistic short-term memory (STM) are typically measured with forward span tasks in which participants are asked to recall lists of words in the order presented. Using such tasks, native signers of American Sign Language (ASL) exhibit smaller spans than native speakers ([Boutla, M., Supalla, T., Newport, E. L., & Bavelier, D.…

  19. Short-term pre- and post-operative stress prolongs incision-induced pain hypersensitivity without changing basal pain perception.

    Science.gov (United States)

    Cao, Jing; Wang, Po-Kai; Tiwari, Vinod; Liang, Lingli; Lutz, Brianna Marie; Shieh, Kun-Ruey; Zang, Wei-Dong; Kaufman, Andrew G; Bekker, Alex; Gao, Xiao-Qun; Tao, Yuan-Xiang

    2015-12-02

    Chronic stress has been reported to increase basal pain sensitivity and/or exacerbate existing persistent pain. However, most surgical patients have normal physiological and psychological health status such as normal pain perception before surgery although they do experience short-term stress during pre- and post-operative periods. Whether or not this short-term stress affects persistent postsurgical pain is unclear. In this study, we showed that pre- or post-surgical exposure to immobilization 6 h daily for three consecutive days did not change basal responses to mechanical, thermal, or cold stimuli or peak levels of incision-induced hypersensitivity to these stimuli; however, immobilization did prolong the duration of incision-induced hypersensitivity in both male and female rats. These phenomena were also observed in post-surgical exposure to forced swimming 25 min daily for 3 consecutive days. Short-term stress induced by immobilization was demonstrated by an elevation in the level of serum corticosterone, an increase in swim immobility, and a decrease in sucrose consumption. Blocking this short-term stress via intrathecal administration of a selective glucocorticoid receptor antagonist, RU38486, or bilateral adrenalectomy significantly attenuated the prolongation of incision-induced hypersensitivity to mechanical, thermal, and cold stimuli. Our results indicate that short-term stress during the pre- or post-operative period delays postoperative pain recovery although it does not affect basal pain perception. Prevention of short-term stress may facilitate patients' recovery from postoperative pain.

  20. False memory for face in short-term memory and neural activity in human amygdala.

    Science.gov (United States)

    Iidaka, Tetsuya; Harada, Tokiko; Sadato, Norihiro

    2014-12-03

    Human memory is often inaccurate. Similar to words and figures, new faces are often recognized as seen or studied items in long- and short-term memory tests; however, the neural mechanisms underlying this false memory remain elusive. In a previous fMRI study using morphed faces and a standard false memory paradigm, we found that there was a U-shaped response curve of the amygdala to old, new, and lure items. This indicates that the amygdala is more active in response to items that are salient (hit and correct rejection) compared to items that are less salient (false alarm), in terms of memory retrieval. In the present fMRI study, we determined whether the false memory for faces occurs within the short-term memory range (a few seconds), and assessed which neural correlates are involved in veridical and illusory memories. Nineteen healthy participants were scanned by 3T MRI during a short-term memory task using morphed faces. The behavioral results indicated that the occurrence of false memories was within the short-term range. We found that the amygdala displayed a U-shaped response curve to memory items, similar to those observed in our previous study. These results suggest that the amygdala plays a common role in both long- and short-term false memory for faces. We made the following conclusions: First, the amygdala is involved in detecting the saliency of items, in addition to fear, and supports goal-oriented behavior by modulating memory. Second, amygdala activity and response time might be related with a subject's response criterion for similar faces. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Maternal haemoglobin and short-term neonatal outcome in preterm neonates.

    Directory of Open Access Journals (Sweden)

    Elodie Savajols

    Full Text Available To determine whether there is a significant association between maternal haemoglobin measured before delivery and short-term neonatal outcome in very preterm neonates.We included prospectively all live births occurring from 25 to 32+6 weeks of gestation in a tertiary care centre between January 1(st 2009 and December 31(st 2011. Outborn infants and infants presenting with lethal malformations were excluded. Three hundred and thirty-nine mothers and 409 infants met the inclusion criteria. For each mother-infant pair a prospective record of epidemiologic data was performed and maternal haemoglobin concentration recorded within 24 hours before delivery was retrospectively researched. Maternal haemoglobin was divided into quartiles with the second and the third one regarded as reference as they were composed of normal haemoglobin values. Short-term outcome was defined as poor in case of death during hospital stay and/or grades III/IV intraventricular haemorrhage and/or periventricular leukomalacia and/or necessity of ventriculoperitoneal shunt.The global rate of poor short-term neonatal outcome was 11.4% and was significantly associated with low maternal haemoglobin values. This association remained significant after adjustment for antenatal corticosteroids therapy, gestational age, parity, mechanism of preterm birth, mode of delivery and birth weight (aOR = 2.97 CI 95% [1.36-6.47]. There was no relation between short-term neonatal outcome and high maternal haemoglobin concentration values.We show that low maternal haemoglobin concentration at delivery is an independent risk factor for poor short-term neonatal outcome in very preterm neonates. This study is one of the first to show such an association within the preterm population.

  2. Regulatory mechanisms of apoptosis in regularly dividing cells

    Directory of Open Access Journals (Sweden)

    Ribal S Darwish

    2010-08-01

    Full Text Available Ribal S DarwishDepartment of Anesthesiology, Division of Critical Care Medicine, University of Maryland Medical Center, Baltimore, Maryland, USAAbstract: The balance between cell survival and death is essential for normal development and homeostasis of organisms. Apoptosis is a distinct type of cell death with ultrastructural features that are consistent with an active, inherently controlled process. Abnormalities and ­dysregulation of apoptosis contribute to the pathophysiology of multiple disease processes. Apoptosis is strictly regulated by several positive and negative feedback mechanisms that regulate cell death and determine the final outcome after cell exposure to apoptotic stimuli. Mitochondria and caspases are central components of the regulatory mechanisms of ­apoptosis. Recently, noncaspase pathways of apoptosis have been explored through the studies of ­apoptosis-inducing factor and endonuclease G. Multiple difficulties in the apoptosis research relate to apoptosis detection and imaging. This article reviews current understanding of the regulatory mechanisms of apoptosis.Keywords: caspases, apoptosis-inducing factor, apoptosis inhibitory proteins, cytochrome c, mitochondria 

  3. Regulatory Mechanisms in the P4-ATPase Complex

    DEFF Research Database (Denmark)

    Costa, Sara

    . The functionality on the P4-ATPase complex is essential for several cellular processes, such as vesicle-mediated transport. However, the specific role of flippase activity in vesicle biogenesis and the regulatory mechanism behind this process is still poorly understood. In these studies, we identified...... affordable alternative using a microscope-based cytometer. This system can simultaneously provide information on flippase activity and expression levels. Taken together, the findings described in this thesis provide new tools for P4-ATPase characterization and valuable insights into the regulation...

  4. Vitamin D endocrine system after short-term space flight

    Science.gov (United States)

    Rhoten, William B. (Principal Investigator); Sergeev, Igor N. (Principal Investigator)

    1996-01-01

    The exposure of the body to microgravity during space flight causes a series of well-documented changes in Ca(2+) metabolism, yet the cellular/molecular mechanisms leading to these changes are poorly understood. There is some evidence for microgravity-induced alterations in the vitamin D endocrine system, which is known to be primarily involved in the regulation of Ca(2+) metabolism. Vitamin D-dependent Ca(2+) binding proteins, or calbindins, are believed to have a significant role in maintaining cellular Ca(2+) homeostasis. We used immunocytochemical, biochemical and molecular approaches to analyze the expression of calbindin-D(sub 28k) and calbindin-D(sub 9k) in kidneys and intestines of rats flown for 9 days aboard the Spacelab 3 mission. The effects of microgravity on calbindins in rats in space vs. 'grounded' animals (synchronous Animal Enclosure Module controls and tail suspension controls) were compared. Exposure to microgravity resulted in a significant decrease in calbindin-D(sub 28k) content in kidneys and calbindin-D(sub 9k) in the intestine of flight and suspended animals, as measured by enzyme-linked immunosorbent assay (ELISA). Immunocytochemistry (ICC) in combination with quantitative computer image analysis was used to measure in situ the expression of calbindins in kidneys and intestine, and insulin in pancreas. There was a large decrease in the distal tubular cell-associated calbindin-D(sub 28k) and absorptive cell-associated calbindin-D(sub 9k) immunoreactivity in the space and suspension kidneys and intestine, as compared with matched ground controls. No consistent differences in pancreatic insulin immunoreactivity between space, suspension and ground controls was observed. There were significant correlations between results by quantitative ICC and ELISA. Western blot analysis showed no consistent changes in the low levels of intestinal and renal vitamin D receptors. These findings suggest that a decreased expression of calbindins after a short-term

  5. Short-term Treatment of Daumone Improves Hepatic Inflammation in Aged Mice

    OpenAIRE

    Park, Jong Hee; Ha, Hunjoo

    2015-01-01

    Chronic inflammation has been proposed as one of the main molecular mechanisms of aging and age-related diseases. Although evidence in humans is limited, short-term calorie restriction (CR) has been shown to have anti-inflammatory effects in aged experimental animals. We reported on the long-term treatment of daumone, a synthetic pheromone secreted by Caenorhabditis elegans in an energy deficient environment, extends the life-span and attenuates liver injury in aged mice. The present study ex...

  6. Short-Term Changes in Respiratory Biomarkers after Swimming in a Chlorinated Pool

    OpenAIRE

    Font-Ribera, Laia; Kogevinas, Manolis; Zock, Jan-Paul; G?mez, Federico P.; Barreiro, Esther; Nieuwenhuijsen, Mark J.; Fernandez, Pilar; Lourencetti, Carolina; P?rez-Olabarr?a, Maitane; Bustamante, Mariona; Marcos, Ricard; Grimalt, Joan O.; Villanueva, Cristina M.

    2010-01-01

    Background Swimming in chlorinated pools involves exposure to disinfection by-products (DBPs) and has been associated with impaired respiratory health. Objectives We evaluated short-term changes in several respiratory biomarkers to explore mechanisms of potential lung damage related to swimming pool exposure. Methods We measured lung function and biomarkers of airway inflammation [fractional exhaled nitric oxide (FeNO), eight cytokines, and vascular endothelial growth factor (VEGF) in exhaled...

  7. Thermotolerance and Photosystem II Behaviour in Co-occuring Temperate Tree Species Exposed to Short-term Extreme Heat Waves

    Science.gov (United States)

    Guha, A.; Warren, J.; Cummings, C.; Han, J.

    2017-12-01

    Thermal stress can induce irreversible photodamage with longer consequences for plant metabolism. We focused on photosystem II (PSII) behaviour to understand how this complex responds in different co-occuring temperate trees exposed to short-term extreme heat waves. The study was designed for understanding complex heat tolerance mechanisms in trees. During manipulative heat-wave experiments, we monitored instantaneous PSII performance and tracked both transient and chronic PSII damages using chlorophyll a fluorescence characteristics. Fluorescence signals were used to simulate PSII bioenergetic processes. The light (Fv'/Fm') and dark-adapted (Fv/Fm) fluorescence traits including fast induction kinetics (OJIP), electron transport rate, PSII operating efficiency and quenching capacities were significantly affected by the heat treatments. Loss in PSII efficiency was more apparent in species like black cottonwood, yellow poplar, walnuts and conifers, whereas oaks maintained relatively better PSII functions. The post-heat recovery of Fv/Fm varied across the studied species showing differential carry over effects. PSII down-regulation was one of dominant factors for the loss in operational photosynthesis during extreme heat wave events. Both light and dark-adapted fluorescence characteristics showed loss in photo-regulatory functions and photodamage. Some resilient species showed rapid recovery from transient PSII damage, whereas fingerprints of chronic PSII damage were observed in susceptibles. Thresholds for Fv/Fm and non-photochemical quenching were identified for the studied species. PSII malfunctioning was largely associated with the observed photosynthetic down-regulation during heat wave treatments, however, its physiological recovery should be a key factor to determine species resilience to short-term extreme heat wave events.

  8. Short-term uranium price formation: a methodology

    International Nuclear Information System (INIS)

    Hsieh, L.Y.; de Graffenried, C.L.

    1987-01-01

    One of the major problems in analyzing the short-term uranium market is the lack of a well-defined spot market price. The two primary sources of price data covering the US uranium market are the series published by the US Dept. of Energy (DOE) and by the Nuclear Exchange Corporation (NUEXCO), a private brokerage firm. Because of the differences in both definition and coverage, these two series are not directly comparable. In this study, an econometric model was developed for analyzing the interrelationship between short-term uranium price (NUEXCO exchange value), supply, demand, and future price expectations formed by market participants. The validity of this model has been demonstrated by the fact that all simulation statistics derived are highly significant. Three forecasting scenarios were developed in this study

  9. Short-Term Wind Speed Forecasting for Power System Operations

    KAUST Repository

    Zhu, Xinxin

    2012-04-01

    The emphasis on renewable energy and concerns about the environment have led to large-scale wind energy penetration worldwide. However, there are also significant challenges associated with the use of wind energy due to the intermittent and unstable nature of wind. High-quality short-term wind speed forecasting is critical to reliable and secure power system operations. This article begins with an overview of the current status of worldwide wind power developments and future trends. It then reviews some statistical short-term wind speed forecasting models, including traditional time series approaches and more advanced space-time statistical models. It also discusses the evaluation of forecast accuracy, in particular, the need for realistic loss functions. New challenges in wind speed forecasting regarding ramp events and offshore wind farms are also presented. © 2012 The Authors. International Statistical Review © 2012 International Statistical Institute.

  10. Short-term fasting protects mice against γ ray radiation

    International Nuclear Information System (INIS)

    Zhu Shengnan; Gu Xiuling; Song Lian; Tong Jian; Li Jianxiang

    2012-01-01

    Objective: To investigate the antagonistic effects of short-term fasting against 60 Co γ ray radiation. Methods: After fasting ICR mice were irradiated for 3 min at a dose rate of 2.5 Gy/min and then returned to normal diet. General situation, body weight changes, food consumption and toxic status were observed. WBC, organ index and anti-oxidative ability (ROS, SOD, MDA, T-AOC) were analyzed. Results: After 60 Co γ ray radiation, the mice exhibited severe toxic symptoms before death. The survival rates were 0 for control and 12 h group, 12.5% for 48 h group and 50% for 72 h group respectively. ROS production of 72 h group was reduced compared with 0 h group (P<0.05). Conclusion: Short-term fasting may attenuate radiation induced injuries, evidenced by a significant increase in mice survival rate. (authors)

  11. Short-term synaptic plasticity and heterogeneity in neural systems

    Science.gov (United States)

    Mejias, J. F.; Kappen, H. J.; Longtin, A.; Torres, J. J.

    2013-01-01

    We review some recent results on neural dynamics and information processing which arise when considering several biophysical factors of interest, in particular, short-term synaptic plasticity and neural heterogeneity. The inclusion of short-term synaptic plasticity leads to enhanced long-term memory capacities, a higher robustness of memory to noise, and irregularity in the duration of the so-called up cortical states. On the other hand, considering some level of neural heterogeneity in neuron models allows neural systems to optimize information transmission in rate coding and temporal coding, two strategies commonly used by neurons to codify information in many brain areas. In all these studies, analytical approximations can be made to explain the underlying dynamics of these neural systems.

  12. The epidemiology of long- and short-term cancer survivors

    DEFF Research Database (Denmark)

    Jarlbæk, Lene; Christensen, Linda; Bruera, Eduardo

    2014-01-01

    Introduction. In this study, we present data from a population-based cohort of incident cancer patients separated in long- and short-term survivors. Our aim was to procure denominators for use in the planning of rehabilitation and palliative care programs. Material and methods. A registry......-linkage cohort study. All cancer patients, diagnosed from 1993 to 2003 from a 470 000 large population, were followed individually from diagnosis to death or until 31 December 2008. Long-term survivors lived five years or more after the time of the cancer diagnosis (TOCD). Short-term survivors died less than...... and sex. Two-year crude cancer survival seems as a clinically relevant cut point for characterizing potential "denominators" for rehabilitation or palliative care programs. From this cohort of incident cancer patients, and using two-year survival as a cut point, it could be estimated that 54% would...

  13. Short-term depression and transient memory in sensory cortex.

    Science.gov (United States)

    Gillary, Grant; Heydt, Rüdiger von der; Niebur, Ernst

    2017-12-01

    Persistent neuronal activity is usually studied in the context of short-term memory localized in central cortical areas. Recent studies show that early sensory areas also can have persistent representations of stimuli which emerge quickly (over tens of milliseconds) and decay slowly (over seconds). Traditional positive feedback models cannot explain sensory persistence for at least two reasons: (i) They show attractor dynamics, with transient perturbations resulting in a quasi-permanent change of system state, whereas sensory systems return to the original state after a transient. (ii) As we show, those positive feedback models which decay to baseline lose their persistence when their recurrent connections are subject to short-term depression, a common property of excitatory connections in early sensory areas. Dual time constant network behavior has also been implemented by nonlinear afferents producing a large transient input followed by much smaller steady state input. We show that such networks require unphysiologically large onset transients to produce the rise and decay observed in sensory areas. Our study explores how memory and persistence can be implemented in another model class, derivative feedback networks. We show that these networks can operate with two vastly different time courses, changing their state quickly when new information is coming in but retaining it for a long time, and that these capabilities are robust to short-term depression. Specifically, derivative feedback networks with short-term depression that acts differentially on positive and negative feedback projections are capable of dynamically changing their time constant, thus allowing fast onset and slow decay of responses without requiring unrealistically large input transients.

  14. Short-term electric load forecasting using computational intelligence methods

    OpenAIRE

    Jurado, Sergio; Peralta, J.; Nebot, Àngela; Mugica, Francisco; Cortez, Paulo

    2013-01-01

    Accurate time series forecasting is a key issue to support individual and organizational decision making. In this paper, we introduce several methods for short-term electric load forecasting. All the presented methods stem from computational intelligence techniques: Random Forest, Nonlinear Autoregressive Neural Networks, Evolutionary Support Vector Machines and Fuzzy Inductive Reasoning. The performance of the suggested methods is experimentally justified with several experiments carried out...

  15. The Development of Rehearsal in Verbal Short-Term Memory

    OpenAIRE

    Jarrold, Christopher; Hall, Debbora

    2013-01-01

    Verbal short-term memory, as indexed by immediate serial recall tasks (in which participants must recall several stimuli in order, immediately after presentation), develops considerably across middle childhood. One explanation for this age-related change is that children's ability to rehearse verbal material increases during this period, and one particularly influential version of this account is that only older children engage in any form of rehearsal. In this article, we critique evidence t...

  16. Short-term Forecasting Tools for Agricultural Nutrient Management.

    Science.gov (United States)

    Easton, Zachary M; Kleinman, Peter J A; Buda, Anthony R; Goering, Dustin; Emberston, Nichole; Reed, Seann; Drohan, Patrick J; Walter, M Todd; Guinan, Pat; Lory, John A; Sommerlot, Andrew R; Sharpley, Andrew

    2017-11-01

    The advent of real-time, short-term farm management tools is motivated by the need to protect water quality above and beyond the general guidance offered by existing nutrient management plans. Advances in high-performance computing and hydrologic or climate modeling have enabled rapid dissemination of real-time information that can assist landowners and conservation personnel with short-term management planning. This paper reviews short-term decision support tools for agriculture that are under various stages of development and implementation in the United States: (i) Wisconsin's Runoff Risk Advisory Forecast (RRAF) System, (ii) New York's Hydrologically Sensitive Area Prediction Tool, (iii) Virginia's Saturated Area Forecast Model, (iv) Pennsylvania's Fertilizer Forecaster, (v) Washington's Application Risk Management (ARM) System, and (vi) Missouri's Design Storm Notification System. Although these decision support tools differ in their underlying model structure, the resolution at which they are applied, and the hydroclimates to which they are relevant, all provide forecasts (range 24-120 h) of runoff risk or soil moisture saturation derived from National Weather Service Forecast models. Although this review highlights the need for further development of robust and well-supported short-term nutrient management tools, their potential for adoption and ultimate utility requires an understanding of the appropriate context of application, the strategic and operational needs of managers, access to weather forecasts, scales of application (e.g., regional vs. field level), data requirements, and outreach communication structure. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  17. Short-term marginal costs in French agriculture

    OpenAIRE

    Latruffe, Laure; LETORT, Elodie

    2011-01-01

    The paper investigates short-term marginal costs in French agriculture for field cropping, beef cattle, and dairy farms during the period 1995-2006. The multi-input multi-output Symmetric Generalised MacFadden cost function is used, with three variable inputs (crop-specific, animal-specific, energy costs), four outputs and three quasi-fixed inputs. Results indicate that marginal costs are on average lower for crop farms than for livestock samples. However, for crop farms, Common Agricultural ...

  18. Robust Short-Term Memory without Synaptic Learning

    OpenAIRE

    Johnson, Samuel; Marro, J.; Torres, Joaquin J.

    2013-01-01

    Short-term memory in the brain cannot in general be explained the way long-term memory can ??? as a gradual modification of synaptic weights ??? since it takes place too quickly. Theories based on some form of cellular bistability, however, do not seem able to account for the fact that noisy neurons can collectively store information in a robust manner. We show how a sufficiently clustered network of simple model neurons can be instantly induced into metastable states capable of retaining inf...

  19. INCAP - Applying short-term flexibility to control inventories

    OpenAIRE

    Lödding , Hermann; Lohmann , Steffen

    2011-01-01

    Abstract Inventory Based Capacity Control (INCAP) is a very simple method that allows inventory levels to be effectively controlled by using short-term capacity flexibility in make-to-stock settings. Moreover, INCAP can be used for finished goods inventories as well as for semi-finished goods inventories. The basic idea is to define upper and lower inventory limits and to adjust capacities if the inventory level reaches either limit. Should the inventory fall below the lower limit,...

  20. Short-term energy outlook. Quarterly projections, first quarter 1995

    International Nuclear Information System (INIS)

    1995-02-01

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). The forecast period for this issue of the Outlook extends from the first quarter of 1995 through the fourth quarter of 1996. Values for the fourth quarter of 1994, however, are preliminary EIA estimates or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data, compiled into the first quarter 1995 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service. The cases are produced using the Short-Term Integrated Forecasting System (STIFS). The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. The EIA model is available on computer tape from the National Technical Information Service

  1. Adult neurogenesis supports short-term olfactory memory.

    Science.gov (United States)

    Arenkiel, Benjamin R

    2010-06-01

    Adult neurogenesis has captivated neuroscientists for decades, with hopes that understanding the programs underlying this phenomenon may provide unique insight toward avenues for brain repair. Interestingly, however, despite intense molecular and cellular investigation, the evolutionary roles and biological functions for ongoing neurogenesis have remained elusive. Here I review recent work published in the Journal of Neuroscience that reveals a functional role for continued neurogenesis toward forming short-term olfactory memories.

  2. Determinants of Short-Term Export Performance in Pakistan

    OpenAIRE

    Subhani, Muhammad Imtiaz; Osman, Ms.Amber; Habib, Sukaina

    2010-01-01

    This research investigates the interdependency between independent (Increase of pricing strategy adaptation, Increase of export intensity, Firm's commitment to exporting, Export market development, Export market competition, Past Pricing Strategy Adaptation, Past Export Performance Satisfaction, Past Export Intensity, Export market distance) and dependent variables (i.e. Expected Short-Term Export Performance improvement) of export performance. The framework is tested via a survey through que...

  3. Frequency-specific insight into short-term memory capacity.

    Science.gov (United States)

    Feurra, Matteo; Galli, Giulia; Pavone, Enea Francesco; Rossi, Alessandro; Rossi, Simone

    2016-07-01

    The digit span is one of the most widely used memory tests in clinical and experimental neuropsychology for reliably measuring short-term memory capacity. In the forward version, sequences of digits of increasing length have to be reproduced in the order in which they are presented, whereas in the backward version items must be reproduced in the reversed order. Here, we assessed whether transcranial alternating current stimulation (tACS) increases the memory span for digits of young and midlife adults. Imperceptibly weak electrical currents in the alpha (10 Hz), beta (20 Hz), theta (5 Hz), and gamma (40 Hz) range, as well as a sham stimulation, were delivered over the left posterior parietal cortex, a cortical region thought to sustain maintenance processes in short-term memory through oscillatory brain activity in the beta range. We showed a frequency-specific effect of beta-tACS that robustly increased the forward memory span of young, but not middle-aged, healthy individuals. The effect correlated with age: the younger the subjects, the greater the benefit arising from parietal beta stimulation. Our results provide evidence of a short-term memory capacity improvement in young adults by online frequency-specific tACS application. Copyright © 2016 the American Physiological Society.

  4. Identity modulates short-term memory for facial emotion.

    Science.gov (United States)

    Galster, Murray; Kahana, Michael J; Wilson, Hugh R; Sekuler, Robert

    2009-12-01

    For some time, the relationship between processing of facial expression and facial identity has been in dispute. Using realistic synthetic faces, we reexamined this relationship for both perception and short-term memory. In Experiment 1, subjects tried to identify whether the emotional expression on a probe stimulus face matched the emotional expression on either of two remembered faces that they had just seen. The results showed that identity strongly influenced recognition short-term memory for emotional expression. In Experiment 2, subjects' similarity/dissimilarity judgments were transformed by multidimensional scaling (MDS) into a 2-D description of the faces' perceptual representations. Distances among stimuli in the MDS representation, which showed a strong linkage of emotional expression and facial identity, were good predictors of correct and false recognitions obtained previously in Experiment 1. The convergence of the results from Experiments 1 and 2 suggests that the overall structure and configuration of faces' perceptual representations may parallel their representation in short-term memory and that facial identity modulates the representation of facial emotion, both in perception and in memory. The stimuli from this study may be downloaded from http://cabn.psychonomic-journals.org/content/supplemental.

  5. Reinsurance by short-term reinsurers in South Africa

    Directory of Open Access Journals (Sweden)

    Fernhout, C. L. R.

    2016-02-01

    Full Text Available The short-term reinsurance process usually involves three parties, namely the insurer, the reinsurer and the original policyholder, as the insurer cedes a part of the covered risk of the policyholder to the reinsurer. This research however addresses the perceptions of reinsurers regarding their reinsurance activities, where the reinsurer sells reinsurance to other insurance entities (viz. insurers and reinsurers, as well as buys reinsurance from other insurance entities. The crux of short-term reinsurance is therefore mutually loss sharing between the various insurance entities. The objective of this research focuses on the improvement of financial decision-making regarding the reinsurance operations of the reinsurers. To achieve this objective a literature study was undertaken to provide adequate background to compile a questionnaire for the empirical survey. The primary study embodies the perceptions of the South African short-term reinsurers regarding the following aspects: the various reasons why reinsurance occurs; the contracts / methods of reinsurance; the bases / forms of reinsurance; and the factors which determine the retention levels of a reinsurer. South Africa is classified as a developing economy, is a member of the BRICS countries and has an emerging market economy. The empirical results should therefore also be valuable to other countries which are classified similarly

  6. Short-term indicators. Intensities as a proxy for savings

    Energy Technology Data Exchange (ETDEWEB)

    Boonekamp, P.G.M.; Gerdes, J. [ECN Policy Studies, Petten (Netherlands); Faberi, S. [Institute of Studies for the Integration of Systems ISIS, Rome (Italy)

    2013-12-15

    The ODYSSEE database on energy efficiency indicators (www.odyssee-indicators.org) has been set up to enable the monitoring and evaluation of realised energy efficiency improvements and related energy savings. The database covers the 27 EU countries as well as Norway and Croatia and data are available from 1990 on. This work contributes to the growing need for quantitative monitoring and evaluation of the impacts of energy policies and measures, both at the EU and national level, e.g. due to the Energy Services Directive and the proposed Energy Efficiency Directive. Because the underlying data become available only after some time, the savings figures are not always timely available. This is especially true for the ODEX efficiency indices per sector that rely on a number of indicators. Therefore, there is a need for so-called short-term indicators that become available shortly after the year has passed for which data are needed. The short term indicators do not replace the savings indicators but function as a proxy for the savings in the most recent year. This proxy value is faster available, but will be less accurate than the saving indicators themselves. The short term indicators have to be checked regularly with the ODEX indicators in order to see whether they can function still as a proxy.

  7. Does tonality boost short-term memory in congenital amusia?

    Science.gov (United States)

    Albouy, Philippe; Schulze, Katrin; Caclin, Anne; Tillmann, Barbara

    2013-11-06

    Congenital amusia is a neuro-developmental disorder of music perception and production. Recent findings have demonstrated that this deficit is linked to an impaired short-term memory for tone sequences. As it has been shown before that non-musicians' implicit knowledge of musical regularities can improve short-term memory for tone information, the present study investigated if this type of implicit knowledge could also influence amusics' short-term memory performance. Congenital amusics and their matched controls, who were non-musicians, had to indicate whether sequences of five tones, presented in pairs, were the same or different; half of the pairs respected musical regularities (tonal sequences) and the other half did not (atonal sequences). As previously reported for non-musician participants, the control participants showed better performance (as measured with d') for tonal sequences than for atonal ones. While this improvement was not observed in amusics, both control and amusic participants showed faster response times for tonal sequences than for atonal sequences. These findings suggest that some implicit processing of tonal structures is potentially preserved in congenital amusia. This observation is encouraging as it strengthens the perspective to exploit implicit knowledge to help reducing pitch perception and memory deficits in amusia. © 2013 Elsevier B.V. All rights reserved.

  8. FFT transformed quantitative EEG analysis of short term memory load.

    Science.gov (United States)

    Singh, Yogesh; Singh, Jayvardhan; Sharma, Ratna; Talwar, Anjana

    2015-07-01

    The EEG is considered as building block of functional signaling in the brain. The role of EEG oscillations in human information processing has been intensively investigated. To study the quantitative EEG correlates of short term memory load as assessed through Sternberg memory test. The study was conducted on 34 healthy male student volunteers. The intervention consisted of Sternberg memory test, which runs on a version of the Sternberg memory scanning paradigm software on a computer. Electroencephalography (EEG) was recorded from 19 scalp locations according to 10-20 international system of electrode placement. EEG signals were analyzed offline. To overcome the problems of fixed band system, individual alpha frequency (IAF) based frequency band selection method was adopted. The outcome measures were FFT transformed absolute powers in the six bands at 19 electrode positions. Sternberg memory test served as model of short term memory load. Correlation analysis of EEG during memory task was reflected as decreased absolute power in Upper alpha band in nearly all the electrode positions; increased power in Theta band at Fronto-Temporal region and Lower 1 alpha band at Fronto-Central region. Lower 2 alpha, Beta and Gamma band power remained unchanged. Short term memory load has distinct electroencephalographic correlates resembling the mentally stressed state. This is evident from decreased power in Upper alpha band (corresponding to Alpha band of traditional EEG system) which is representative band of relaxed mental state. Fronto-temporal Theta power changes may reflect the encoding and execution of memory task.

  9. Short-term energy outlook: Quarterly projections, fourth quarter 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-14

    The Energy Information Administration (EIA) prepares quarterly short-term energy supply, demand, and price projections for printed publication in January, April, July, and October in the Short-Term Energy Outlook. The details of these projections, as well as monthly updates on or about the 6th of each interim month, are available on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. The forecast period for this issue of the Outlook extends from the fourth quarter of 1997 through the fourth quarter of 1998. Values for the fourth quarter of 1997, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the fourth quarter 1997 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. 19 tabs.

  10. Short-term forecasting model for aggregated regional hydropower generation

    International Nuclear Information System (INIS)

    Monteiro, Claudio; Ramirez-Rosado, Ignacio J.; Fernandez-Jimenez, L. Alfredo

    2014-01-01

    Highlights: • Original short-term forecasting model for the hourly hydropower generation. • The use of NWP forecasts allows horizons of several days. • New variable to represent the capacity level for generating hydroelectric energy. • The proposed model significantly outperforms the persistence model. - Abstract: This paper presents an original short-term forecasting model of the hourly electric power production for aggregated regional hydropower generation. The inputs of the model are previously recorded values of the aggregated hourly production of hydropower plants and hourly water precipitation forecasts using Numerical Weather Prediction tools, as well as other hourly data (load demand and wind generation). This model is composed of three modules: the first one gives the prediction of the “monthly” hourly power production of the hydropower plants; the second module gives the prediction of hourly power deviation values, which are added to that obtained by the first module to achieve the final forecast of the hourly hydropower generation; the third module allows a periodic adjustment of the prediction of the first module to improve its BIAS error. The model has been applied successfully to the real-life case study of the short-term forecasting of the aggregated hydropower generation in Spain and Portugal (Iberian Peninsula Power System), achieving satisfactory results for the next-day forecasts. The model can be valuable for agents involved in electricity markets and useful for power system operations

  11. Transcriptional regulatory network triggered by oxidative signals configures the early response mechanisms of japonica rice to chilling stress

    Directory of Open Access Journals (Sweden)

    Wijaya Edward

    2010-01-01

    Full Text Available Abstract Background The transcriptional regulatory network involved in low temperature response leading to acclimation has been established in Arabidopsis. In japonica rice, which can only withstand transient exposure to milder cold stress (10°C, an oxidative-mediated network has been proposed to play a key role in configuring early responses and short-term defenses. The components, hierarchical organization and physiological consequences of this network were further dissected by a systems-level approach. Results Regulatory clusters responding directly to oxidative signals were prominent during the initial 6 to 12 hours at 10°C. Early events mirrored a typical oxidative response based on striking similarities of the transcriptome to disease, elicitor and wounding induced processes. Targets of oxidative-mediated mechanisms are likely regulated by several classes of bZIP factors acting on as1/ocs/TGA-like element enriched clusters, ERF factors acting on GCC-box/JAre-like element enriched clusters and R2R3-MYB factors acting on MYB2-like element enriched clusters. Temporal induction of several H2O2-induced bZIP, ERF and MYB genes coincided with the transient H2O2 spikes within the initial 6 to 12 hours. Oxidative-independent responses involve DREB/CBF, RAP2 and RAV1 factors acting on DRE/CRT/rav1-like enriched clusters and bZIP factors acting on ABRE-like enriched clusters. Oxidative-mediated clusters were activated earlier than ABA-mediated clusters. Conclusion Genome-wide, physiological and whole-plant level analyses established a holistic view of chilling stress response mechanism of japonica rice. Early response regulatory network triggered by oxidative signals is critical for prolonged survival under sub-optimal temperature. Integration of stress and developmental responses leads to modulated growth and vigor maintenance contributing to a delay of plastic injuries.

  12. Transcriptional regulatory network triggered by oxidative signals configures the early response mechanisms of japonica rice to chilling stress

    KAUST Repository

    Yun, Kil-Young

    2010-01-25

    Background: The transcriptional regulatory network involved in low temperature response leading to acclimation has been established in Arabidopsis. In japonica rice, which can only withstand transient exposure to milder cold stress (10C), an oxidative-mediated network has been proposed to play a key role in configuring early responses and short-term defenses. The components, hierarchical organization and physiological consequences of this network were further dissected by a systems-level approach.Results: Regulatory clusters responding directly to oxidative signals were prominent during the initial 6 to 12 hours at 10C. Early events mirrored a typical oxidative response based on striking similarities of the transcriptome to disease, elicitor and wounding induced processes. Targets of oxidative-mediated mechanisms are likely regulated by several classes of bZIP factors acting on as1/ocs/TGA-like element enriched clusters, ERF factors acting on GCC-box/JAre-like element enriched clusters and R2R3-MYB factors acting on MYB2-like element enriched clusters.Temporal induction of several H2O2-induced bZIP, ERF and MYB genes coincided with the transient H2O2spikes within the initial 6 to 12 hours. Oxidative-independent responses involve DREB/CBF, RAP2 and RAV1 factors acting on DRE/CRT/rav1-like enriched clusters and bZIP factors acting on ABRE-like enriched clusters. Oxidative-mediated clusters were activated earlier than ABA-mediated clusters.Conclusion: Genome-wide, physiological and whole-plant level analyses established a holistic view of chilling stress response mechanism of japonica rice. Early response regulatory network triggered by oxidative signals is critical for prolonged survival under sub-optimal temperature. Integration of stress and developmental responses leads to modulated growth and vigor maintenance contributing to a delay of plastic injuries. 2010 Yun et al; licensee BioMed Central Ltd.

  13. The uranium industry: long-term planning for short-term competition

    International Nuclear Information System (INIS)

    Vottero, X.; Georges Capus, G.

    2001-01-01

    Long term planning for short term competition Today, uranium producers face new challenges in terms of both production (new regulatory, environmental and social constraints) and market conditions (new sources of uranium supply, very low prices and tough competition). In such a context, long-term planning is not just a prerequisite to survive in the nuclear fuel cycle industry. In fact, it also contributes to sustaining nuclear electricity generation facing fierce competition from other energy sources in increasingly deregulated markets. Firstly, the risk of investing in new mining projects in western countries is growing because, on the one hand, of very erratic market conditions and, on the other hand, of increasingly lengthy, complex and unpredictable regulatory conditions. Secondly, the supply of other sources of uranium (uranium derived from nuclear weapons, uranium produced in CIS countries, ...) involve other risks, mainly related to politics and commercial restrictions. Consequently, competitive uranium supply requires not only technical competence but also financial strength and good marketing capabilities in order to anticipate long-term market trends, in terms of both demand and supply. It also requires taking into account new parameters such as politics, environment, regulations, etc. Today, a supplier dedicated to the sustainable production of nuclear electricity must manage a broad range of long-term risks inherent to the procurement of uranium. Taking into account all these parameters in a context of short-term, fast-changing market is a great challenge for the future generation. World Uranium Civilian Supply and Demand. (authors)

  14. Mercury simulations within GMOS: Analysis of short-term observational episodes

    Directory of Open Access Journals (Sweden)

    Travnikov O.

    2013-04-01

    Full Text Available A number of contemporary chemical transport models for mercury are applied within the framework of the EU GMOS project to study principal processes of mercury transport and transformations in the atmosphere. Each model is involved in simulation of short-term episodes corresponding to particular Hg measurement campaigns in Europe and other regions. In order to evaluate different physical and chemical mechanisms the models perform sensitivity runs with various parameterizations and/or combinations of considered processes. The modeling results are compared to detailed measurements of Hg species (Hg0/TGM, RGM, HgP with high temporal resolution (hours aiming at reproduction of short-term temporal variability of Hg air concentration.

  15. Ordered short-term memory differs in signers and speakers: Implications for models of short-term memory

    OpenAIRE

    Bavelier, Daphne; Newport, Elissa L.; Hall, Matt; Supalla, Ted; Boutla, Mrim

    2008-01-01

    Capacity limits in linguistic short-term memory (STM) are typically measured with forward span tasks in which participants are asked to recall lists of words in the order presented. Using such tasks, native signers of American Sign Language (ASL) exhibit smaller spans than native speakers (Boutla, Supalla, Newport, & Bavelier, 2004). Here, we test the hypothesis that this population difference reflects differences in the way speakers and signers maintain temporal order information in short-te...

  16. Short-term memory load and pronunciation rate

    Science.gov (United States)

    Schweickert, Richard; Hayt, Cathrin

    1988-01-01

    In a test of short-term memory recall, two subjects attempted to recall various lists. For unpracticed subjects, the time it took to read the list is a better predictor of immediate recall than the number of items on the list. For practiced subjects, the two predictors do about equally well. If the items that must be recalled are unfamiliar, it is advantageous to keep the items short to pronounce. On the other hand, if the same items will be encountered over and over again, it is advantageous to make them distinctive, even at the cost of adding to the number of syllables.

  17. Short-term memory, executive control, and children's route learning

    OpenAIRE

    Purser, H. R.; Farran, E. K.; Courbois, Y.; Lemahieu, A.; Mellier, D.; Sockeel, P.; Blades, M.

    2012-01-01

    The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and visuospatial long-term memory; the route-learning task was conducted using a maze in a virtual environment. In contrast to previous research, correlation...

  18. A Simple Hybrid Model for Short-Term Load Forecasting

    Directory of Open Access Journals (Sweden)

    Suseelatha Annamareddi

    2013-01-01

    Full Text Available The paper proposes a simple hybrid model to forecast the electrical load data based on the wavelet transform technique and double exponential smoothing. The historical noisy load series data is decomposed into deterministic and fluctuation components using suitable wavelet coefficient thresholds and wavelet reconstruction method. The variation characteristics of the resulting series are analyzed to arrive at reasonable thresholds that yield good denoising results. The constitutive series are then forecasted using appropriate exponential adaptive smoothing models. A case study performed on California energy market data demonstrates that the proposed method can offer high forecasting precision for very short-term forecasts, considering a time horizon of two weeks.

  19. Short-Term Memory and Its Biophysical Model

    Science.gov (United States)

    Wang, Wei; Zhang, Kai; Tang, Xiao-wei

    1996-12-01

    The capacity of short-term memory has been studied using an integrate-and-fire neuronal network model. It is found that the storage of events depend on the manner of the correlation between the events, and the capacity is dominated by the value of after-depolarization potential. There is a monotonic increasing relationship between the value of after-depolarization potential and the memory numbers. The biophysics relevance of the network model is discussed and different kinds of the information processes are studied too.

  20. Overwriting and intrusion in short-term memory.

    Science.gov (United States)

    Bancroft, Tyler D; Jones, Jeffery A; Ensor, Tyler M; Hockley, William E; Servos, Philip

    2016-04-01

    Studies of interference in working and short-term memory suggest that irrelevant information may overwrite the contents of memory or intrude into memory. While some previous studies have reported greater interference when irrelevant information is similar to the contents of memory than when it is dissimilar, other studies have reported greater interference for dissimilar distractors than for similar distractors. In the present study, we find the latter effect in a paradigm that uses auditory tones as stimuli. We suggest that the effects of distractor similarity to memory contents are mediated by the type of information held in memory, particularly the complexity or simplicity of information.

  1. Short-term memory for spatial, sequential and duration information.

    Science.gov (United States)

    Manohar, Sanjay G; Pertzov, Yoni; Husain, Masud

    2017-10-01

    Space and time appear to play key roles in the way that information is organized in short-term memory (STM). Some argue that they are crucial contexts within which other stored features are embedded, allowing binding of information that belongs together within STM. Here we review recent behavioral, neurophysiological and imaging studies that have sought to investigate the nature of spatial, sequential and duration representations in STM, and how these might break down in disease. Findings from these studies point to an important role of the hippocampus and other medial temporal lobe structures in aspects of STM, challenging conventional accounts of involvement of these regions in only long-term memory.

  2. Music Learning with Long Short Term Memory Networks

    OpenAIRE

    Colombo, Florian François

    2015-01-01

    Humans are able to learn and compose complex, yet beautiful, pieces of music as seen in e.g. the highly complicated works of J.S. Bach. However, how our brain is able to store and produce these very long temporal sequences is still an open question. Long short-term memory (LSTM) artificial neural networks have been shown to be efficient in sequence learning tasks thanks to their inherent ability to bridge long time lags between input events and their target signals. Here, I investigate the po...

  3. Short-term energy outlook, quarterly projections, second quarter 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    The Energy Information Administration (EIA) prepares quarterly short-term energy supply, demand, and price projections. The details of these projections, as well as monthly updates, are available on the Internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. The paper discusses outlook assumptions; US energy prices; world oil supply and the oil production cutback agreement of March 1998; international oil demand and supply; world oil stocks, capacity, and net trade; US oil demand and supply; US natural gas demand and supply; US coal demand and supply; US electricity demand and supply; US renewable energy demand; and US energy demand and supply sensitivities. 29 figs., 19 tabs.

  4. Short-term hydropower production planning by stochastic programming

    DEFF Research Database (Denmark)

    Fleten, Stein-Erik; Kristoffersen, Trine

    2008-01-01

    -term production planning a matter of spatial distribution among the reservoirs of the plant. Day-ahead market prices and reservoir inflows are, however, uncertain beyond the current operation day and water must be allocated among the reservoirs in order to strike a balance between current profits and expected......Within the framework of multi-stage mixed-integer linear stochastic programming we develop a short-term production plan for a price-taking hydropower plant operating under uncertainty. Current production must comply with the day-ahead commitments of the previous day which makes short...

  5. MHz gravitational waves from short-term anisotropic inflation

    International Nuclear Information System (INIS)

    Ito, Asuka; Soda, Jiro

    2016-01-01

    We reveal the universality of short-term anisotropic inflation. As a demonstration, we study inflation with an exponential type gauge kinetic function which is ubiquitous in models obtained by dimensional reduction from higher dimensional fundamental theory. It turns out that an anisotropic inflation universally takes place in the later stage of conventional inflation. Remarkably, we find that primordial gravitational waves with a peak amplitude around 10 −26 ∼10 −27 are copiously produced in high-frequency bands 10 MHz∼100 MHz. If we could detect such gravitational waves in future, we would be able to probe higher dimensional fundamental theory.

  6. Short-term bioconcentration studies of Np in freshwater biota

    International Nuclear Information System (INIS)

    Poston, T.M.; Klopfer, D.C.; Simmons, M.A.

    1990-01-01

    Short-term laboratory exposures were conducted to determine the potential accumulation of Np in aquatic organisms. Concentration factors were highest in green algae. Daphnia magna, a filter-feeding crustacean, accumulated Np at levels one order of magnitude greater than the amphipod Gammarus sp., an omnivorous substrate feeder. Accumulation of Np in juvenile rainbow trout (Oncorhynchus mykiss) was highest in carcass (generally greater than 78% of the total body burden) and lowest in fillets. Recommended concentration factors for Np, based on fresh weight, were 300 for green algae, 100 for filter-feeding invertebrates, for nonfilter-feeding invertebrates, 10 for whole fish, and one for fish flesh

  7. Short-Term Treatment of Children With Encopresis

    Science.gov (United States)

    FIREMAN, GARY; KOPLEWICZ, HAROLD S.

    1992-01-01

    To examine the effectiveness of a short-term behavioral treatment of encopresis, 52 encopretic children were evaluated and treated according to a standardized protocol. The treatment was highly effective, with a significant decrease in soiling during the first month (P < 0.01). Of the children who began treatment, 84.6% successfully reached the criterion of 2 consecutive weeks with no soiling accidents in a mean time of 28 days, and 78.8% successfully completed an additional 7-week phaseout period. The evaluations provided rich descriptive information regarding the characteristics of encopretic children. In agreement with the literature, no specific pattern of behavioral pathology was apparent. PMID:22700057

  8. Short-term load forecasting with increment regression tree

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jingfei; Stenzel, Juergen [Darmstadt University of Techonology, Darmstadt 64283 (Germany)

    2006-06-15

    This paper presents a new regression tree method for short-term load forecasting. Both increment and non-increment tree are built according to the historical data to provide the data space partition and input variable selection. Support vector machine is employed to the samples of regression tree nodes for further fine regression. Results of different tree nodes are integrated through weighted average method to obtain the comprehensive forecasting result. The effectiveness of the proposed method is demonstrated through its application to an actual system. (author)

  9. Impact of short-term severe accident management actions in a long-term perspective. Final Report

    International Nuclear Information System (INIS)

    2000-03-01

    The present systems for severe accident management are focused on mitigating the consequences of special severe accident phenomena and to reach a safe plant state. However, in the development of strategies and procedures for severe accident management, it is also important to consider the long-term perspective of accident management and especially to secure the safe state of the plant. The main reason for this is that certain short-term actions have an impact on the long-term scenario. Both positive and negative effects from short-term actions on the accident management in the long-term perspective have been included in this paper. Short-term actions are accident management measures taken within about 24 hours after the initiating event. The purpose of short-term actions is to reach a stable status of the plant. The main goal in the long-term perspective is to maintain the reactor in a stable state and prevent uncontrolled releases of activity. The purpose of this short Technical Note, deliberately limited in scope, is to draw attention to potential long-term problems, important to utilities and regulatory authorities, arising from the way a severe accident would be managed during the first hours. Its objective is to encourage discussions on the safest - and maybe also most economical - way to manage a severe accident in the long term by not making the situation worse through inappropriate short-term actions, and on the identification of short-term actions likely to make long-term management easier and safer. The Note is intended as a contribution to the knowledge base put at the disposal of Member countries through international collaboration. The scope of the work has been limited to a literature search. Useful further activities have been identified. However, there is no proposal, at this stage, for more detailed work to be undertaken under the auspices of the CSNI. Plant-specific applications would need to be developed by utilities

  10. Feature-Based Visual Short-Term Memory Is Widely Distributed and Hierarchically Organized.

    Science.gov (United States)

    Dotson, Nicholas M; Hoffman, Steven J; Goodell, Baldwin; Gray, Charles M

    2018-06-15

    Feature-based visual short-term memory is known to engage both sensory and association cortices. However, the extent of the participating circuit and the neural mechanisms underlying memory maintenance is still a matter of vigorous debate. To address these questions, we recorded neuronal activity from 42 cortical areas in monkeys performing a feature-based visual short-term memory task and an interleaved fixation task. We find that task-dependent differences in firing rates are widely distributed throughout the cortex, while stimulus-specific changes in firing rates are more restricted and hierarchically organized. We also show that microsaccades during the memory delay encode the stimuli held in memory and that units modulated by microsaccades are more likely to exhibit stimulus specificity, suggesting that eye movements contribute to visual short-term memory processes. These results support a framework in which most cortical areas, within a modality, contribute to mnemonic representations at timescales that increase along the cortical hierarchy. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Impact of long-term and short-term therapies on seminal parameters

    Directory of Open Access Journals (Sweden)

    Jlenia Elia

    2013-04-01

    Full Text Available Aim: The aim of this work was: i to evaluate the prevalence of male partners of subfertile couples being treated with long/short term therapies for non andrological diseases; ii to study their seminal profile for the possible effects of their treatments on spermatogenesis and/or epididymal maturation. Methods: The study group was made up of 723 subjects, aged between 25 and 47 years. Semen analysis was performed according to World Health Organization (WHO guidelines (1999. The Superimposed Image Analysis System (SIAS, which is based on the computerized superimposition of spermatozoa images, was used to assess sperm motility parameters. Results: The prevalence of subjects taking pharmacological treatments was 22.7% (164/723. The prevalence was 3.7% (27/723 for the Short-Term Group and 18.9% (137/723 for the Long-Term Group. The subjects of each group were also subdivided into subgroups according to the treatments being received. Regarding the seminal profile, we did not observe a significant difference between the Long-Term, Short-Term or the Control Group. However, regarding the subgroups, we found a significant decrease in sperm number and progressive motility percentage in the subjects receiving treatment with antihypertensive drugs compared with the other subgroups and the Control Group. Conclusions: In the management of infertile couples, the potential negative impact on seminal parameters of any drugs being taken as Long-Term Therapy should be considered. The pathogenic mechanism needs to be clarified.

  12. Psychomotor Ability and Short-term Memory, and Reading and Mathematics Achievement in Children.

    Science.gov (United States)

    Murrihy, Cherée; Bailey, Maria; Roodenburg, John

    2017-08-01

    The aim of our study was to examine whether the findings from previous research, indicating the role of short-term memory as a mediator of the relationship between motor coordination and academic achievement in adolescents, is also evident in a younger child population. The study utilized a quantative cross-sectional design involving 133 children aged 8-12. The McCarron Assessment of Neuromuscular Development (MAND) provided four indicators of psychomotor ability (Finger Nose, Walking, Balancing, and Jumping). The Woodcock-Johnson Cognitive battery and the Automated Working Memory Assessment (AWMA) provided two measures of short-term memory (Numbers Reversed and Digit Recall) and the WJIII Achievement battery provided two measures of reading achievement (Letter-word Identification and Passage Comprehension) and two measures of mathematics achievement (Applied Problems and Calculation). Structural equation modeling was used, controlling for age, processing speed, crystallized, and fluid intelligence where appropriate. The results found support for the hypothesis that short-term memory fully mediates the relationship between psychomotor ability and reading and mathematics achievement. These findings indicate the significant affect of psychomotor ability on learning outcomes and consequently the need to assess these in considering learning difficulties, and as such these findings also advance understanding of developmental neural mechanisms underpinning the relationships. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Attentional control constrains visual short-term memory: Insights from developmental and individual differences

    Science.gov (United States)

    Astle, D.E.; Nobre, A.C.; Scerif, G.

    2014-01-01

    The mechanisms by which attentional control biases mnemonic representations have attracted much interest but remain poorly understood. As attention and memory develop gradually over childhood and variably across individuals, assessing how participants of different ages and ability attend to mnemonic contents can elucidate their interplay. In Experiment 1, 7-, 10-year-olds and adults were asked to report whether a probe item had been part of a previously presented four-item array. The initial array could either be uncued, preceded (“pre-cued”) or followed (“retro-cued”) by a spatial cue orienting attention to one of the potential item locations. Performance across groups was significantly improved by both cue types and individual differences in children’s retrospective attentional control predicted their visual short-term and working memory span, whereas their basic ability to remember in the absence of cues did not. Experiment 2 imposed a variable delay between the array and the subsequent orienting cue. Cueing benefits were greater in adults compared to 10-year-olds, but they persisted even when cues followed the array by nearly 3 seconds, suggesting that orienting operated on durable short-term representations for both age groups. The findings indicate that there are substantial developmental and individual differences in the ability to control attention to memory and that in turn these differences constrain visual short-term memory capacity. PMID:20680889

  14. Factors Influencing Short-term Synaptic Plasticity in the Avian Cochlear Nucleus Magnocellularis

    Directory of Open Access Journals (Sweden)

    Jason Tait Sanchez Quinones

    2015-01-01

    Full Text Available Defined as reduced neural responses during high rates of activity, synaptic depression is a form of short-term plasticity important for the temporal filtering of sound. In the avian cochlear nucleus magnocellularis (NM, an auditory brainstem structure, mechanisms regulating short-term synaptic depression include pre-, post-, and extrasynaptic factors. Using varied paired-pulse stimulus intervals, we found that the time course of synaptic depression lasts up to four seconds at late-developing NM synapses. Synaptic depression was largely reliant on exogenous Ca 2+ -dependent probability of presynaptic neurotransmitter release, and to a lesser extent, on the desensitization of postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptor (AMPA-R. Interestingly, although extrasynaptic glutamate clearance did not play a significant role in regulating synaptic depression, blocking glutamate clearance at early-developing synapses altered synaptic dynamics, changing responses from depression to facilitation. These results suggest a developmental shift in the relative reliance on pre-, post-, and extrasynaptic factors in regulating short-term synaptic plasticity in NM.

  15. Direct current induced short-term modulation of the left dorsolateral prefrontal cortex while learning auditory presented nouns

    Directory of Open Access Journals (Sweden)

    Meyer Martin

    2009-07-01

    Full Text Available Abstract Background Little is known about the contribution of transcranial direct current stimulation (tDCS to the exploration of memory functions. The aim of the present study was to examine the behavioural effects of right or left-hemisphere frontal direct current delivery while committing to memory auditory presented nouns on short-term learning and subsequent long-term retrieval. Methods Twenty subjects, divided into two groups, performed an episodic verbal memory task during anodal, cathodal and sham current application on the right or left dorsolateral prefrontal cortex (DLPFC. Results Our results imply that only cathodal tDCS elicits behavioural effects on verbal memory performance. In particular, left-sided application of cathodal tDCS impaired short-term verbal learning when compared to the baseline. We did not observe tDCS effects on long-term retrieval. Conclusion Our results imply that the left DLPFC is a crucial area involved in short-term verbal learning mechanisms. However, we found further support that direct current delivery with an intensity of 1.5 mA to the DLPFC during short-term learning does not disrupt longer lasting consolidation processes that are mainly known to be related to mesial temporal lobe areas. In the present study, we have shown that the tDCS technique has the potential to modulate short-term verbal learning mechanism.

  16. Short-Term Monocular Deprivation Enhances Physiological Pupillary Oscillations

    Directory of Open Access Journals (Sweden)

    Paola Binda

    2017-01-01

    Full Text Available Short-term monocular deprivation alters visual perception in adult humans, increasing the dominance of the deprived eye, for example, as measured with binocular rivalry. This form of plasticity may depend upon the inhibition/excitation balance in the visual cortex. Recent work suggests that cortical excitability is reliably tracked by dilations and constrictions of the pupils of the eyes. Here, we ask whether monocular deprivation produces a systematic change of pupil behavior, as measured at rest, that is independent of the change of visual perception. During periods of minimal sensory stimulation (in the dark and task requirements (minimizing body and gaze movements, slow pupil oscillations, “hippus,” spontaneously appear. We find that hippus amplitude increases after monocular deprivation, with larger hippus changes in participants showing larger ocular dominance changes (measured by binocular rivalry. This tight correlation suggests that a single latent variable explains both the change of ocular dominance and hippus. We speculate that the neurotransmitter norepinephrine may be implicated in this phenomenon, given its important role in both plasticity and pupil control. On the practical side, our results indicate that measuring the pupil hippus (a simple and short procedure provides a sensitive index of the change of ocular dominance induced by short-term monocular deprivation, hence a proxy for plasticity.

  17. An accident diagnosis algorithm using long short-term memory

    Directory of Open Access Journals (Sweden)

    Jaemin Yang

    2018-05-01

    Full Text Available Accident diagnosis is one of the complex tasks for nuclear power plant (NPP operators. In abnormal or emergency situations, the diagnostic activity of the NPP states is burdensome though necessary. Numerous computer-based methods and operator support systems have been suggested to address this problem. Among them, the recurrent neural network (RNN has performed well at analyzing time series data. This study proposes an algorithm for accident diagnosis using long short-term memory (LSTM, which is a kind of RNN, which improves the limitation for time reflection. The algorithm consists of preprocessing, the LSTM network, and postprocessing. In the LSTM-based algorithm, preprocessed input variables are calculated to output the accident diagnosis results. The outputs are also postprocessed using softmax to determine the ranking of accident diagnosis results with probabilities. This algorithm was trained using a compact nuclear simulator for several accidents: a loss of coolant accident, a steam generator tube rupture, and a main steam line break. The trained algorithm was also tested to demonstrate the feasibility of diagnosing NPP accidents. Keywords: Accident Diagnosis, Long Short-term Memory, Recurrent Neural Network, Softmax

  18. Short term efficacy of interventional therapy for hilar biliary obstruction

    International Nuclear Information System (INIS)

    Zhai Renyou; Dai Dingke; Wang Jianfeng; Yu Ping; Wei Baojie

    2006-01-01

    Objective: To analyze the method and short term efficacy of interventional therapy for hilar biliary obstructive jaundice. Methods: 100 consecutive patients with perihilar biliary obstruction admitted before May 2004 were treated with percutaneous transhepatic biliary drainage (PTBD) or placement of metallic stents. Among them, 39 patients were found with bile duct cancer, 6 with adenocarcinoma of gallbladder, 22 with metastatic carcinoma, 15 with primary liver carcinoma and 18 with bile duct strait after liver transplantation. Serum total bilirubin before operation and 3-7 days, 8-14 days after procedure were analysed by t test. Results: 79 patients with PTBD (including simple external drainage and combined internal and external drainage), and 21 patients with stents placement (including 31 stents of 4 different kinds) were all carried out successfully. There were significant differences in serum total bilirubin before and 3-7 days, 8-14 days after the procedure, P<0.05 vs P<0.01. Conclusion: Interventional therapy is simple, safe, and effective for hilar biliary obstruction, the latter showed more significance than the former with short term satisfaction. (authors)

  19. Short-Term Lifestyle Strategies for Sustaining Cognitive Status

    Science.gov (United States)

    Morris, John N.; Steel, Knight; Strout, Kelley A.; Fries, Brant E.; Moore, Alice; Garms-Homolová, Vjenka

    2016-01-01

    Cognitive decline impacts older adults, particularly their independence. The goal of this project was to increase understanding of how short-term, everyday lifestyle options, including physical activity, help an older adult sustain cognitive independence. Using a secondary analysis of lifestyle choices, we drew on a dataset of 4,620 community-dwelling elders in the US, assessed at baseline and one year later using 2 valid and reliable tools, the interRAI Community Health Assessment and the interRAI Wellness tool. Decline or no decline on the Cognitive Performance Scale was the dependent variable. We examined sustaining one's status on this measure over a one-year period in relation to key dimensions of wellness through intellectual, physical, emotional, social, and spiritual variables. Engaging in physical activity, formal exercise, and specific recreational activities had a favorable effect on short-term cognitive decline. Involvement with computers, crossword puzzles, handicrafts, and formal education courses also were protective factors. The physical and intellectual domains of wellness are prominent aspects in protection from cognitive decline. Inherent in these two domains are mutable factors suitable for targeted efforts to promote older adult health and well-being. PMID:27891520

  20. Short term exposure to cooking fumes and pulmonary function

    Directory of Open Access Journals (Sweden)

    Qvenild Torgunn

    2009-05-01

    Full Text Available Abstract Background Exposure to cooking fumes may have different deleterious effects on the respiratory system. The aim of this study was to look at possible effects from inhalation of cooking fumes on pulmonary function. Methods Two groups of 12 healthy volunteers (A and B stayed in a model kitchen for two and four hours respectively, and were monitored with spirometry four times during twenty four hours, on one occasion without any exposure, and on another with exposure to controlled levels of cooking fumes. Results The change in spirometric values during the day with exposure to cooking fumes, were not statistically significantly different from the changes during the day without exposure, with the exception of forced expiratory time (FET. The change in FET from entering the kitchen until six hours later, was significantly prolonged between the exposed and the unexposed day with a 15.7% increase on the exposed day, compared to a 3.2% decrease during the unexposed day (p-value = 0.03. The same tendency could be seen for FET measurements done immediately after the exposure and on the next morning, but this was not statistically significant. Conclusion In our experimental setting, there seems to be minor short term spirometric effects, mainly affecting FET, from short term exposure to cooking fumes.

  1. Short-term memory for emotional faces in dysphoria.

    Science.gov (United States)

    Noreen, Saima; Ridout, Nathan

    2010-07-01

    The study aimed to determine if the memory bias for negative faces previously demonstrated in depression and dysphoria generalises from long- to short-term memory. A total of 29 dysphoric (DP) and 22 non-dysphoric (ND) participants were presented with a series of faces and asked to identify the emotion portrayed (happiness, sadness, anger, or neutral affect). Following a delay, four faces were presented (the original plus three distractors) and participants were asked to identify the target face. Half of the trials assessed memory for facial emotion, and the remaining trials examined memory for facial identity. At encoding, no group differences were apparent. At memory testing, relative to ND participants, DP participants exhibited impaired memory for all types of facial emotion and for facial identity when the faces featured happiness, anger, or neutral affect, but not sadness. DP participants exhibited impaired identity memory for happy faces relative to angry, sad, and neutral, whereas ND participants exhibited enhanced facial identity memory when faces were angry. In general, memory for faces was not related to performance at encoding. However, in DP participants only, memory for sad faces was related to sadness recognition at encoding. The results suggest that the negative memory bias for faces in dysphoria does not generalise from long- to short-term memory.

  2. Similarity as an organising principle in short-term memory.

    Science.gov (United States)

    LeCompte, D C; Watkins, M J

    1993-03-01

    The role of stimulus similarity as an organising principle in short-term memory was explored in a series of seven experiments. Each experiment involved the presentation of a short sequence of items that were drawn from two distinct physical classes and arranged such that item class changed after every second item. Following presentation, one item was re-presented as a probe for the 'target' item that had directly followed it in the sequence. Memory for the sequence was considered organised by class if probability of recall was higher when the probe and target were from the same class than when they were from different classes. Such organisation was found when one class was auditory and the other was visual (spoken vs. written words, and sounds vs. pictures). It was also found when both classes were auditory (words spoken in a male voice vs. words spoken in a female voice) and when both classes were visual (digits shown in one location vs. digits shown in another). It is concluded that short-term memory can be organised on the basis of sensory modality and on the basis of certain features within both the auditory and visual modalities.

  3. Short-Term Lifestyle Strategies for Sustaining Cognitive Status

    Directory of Open Access Journals (Sweden)

    Elizabeth P. Howard

    2016-01-01

    Full Text Available Cognitive decline impacts older adults, particularly their independence. The goal of this project was to increase understanding of how short-term, everyday lifestyle options, including physical activity, help an older adult sustain cognitive independence. Using a secondary analysis of lifestyle choices, we drew on a dataset of 4,620 community-dwelling elders in the US, assessed at baseline and one year later using 2 valid and reliable tools, the interRAI Community Health Assessment and the interRAI Wellness tool. Decline or no decline on the Cognitive Performance Scale was the dependent variable. We examined sustaining one’s status on this measure over a one-year period in relation to key dimensions of wellness through intellectual, physical, emotional, social, and spiritual variables. Engaging in physical activity, formal exercise, and specific recreational activities had a favorable effect on short-term cognitive decline. Involvement with computers, crossword puzzles, handicrafts, and formal education courses also were protective factors. The physical and intellectual domains of wellness are prominent aspects in protection from cognitive decline. Inherent in these two domains are mutable factors suitable for targeted efforts to promote older adult health and well-being.

  4. Short-term effects of playing computer games on attention.

    Science.gov (United States)

    Tahiroglu, Aysegul Yolga; Celik, Gonca Gul; Avci, Ayse; Seydaoglu, Gulsah; Uzel, Mehtap; Altunbas, Handan

    2010-05-01

    The main aim of the present study is to investigate the short-term cognitive effects of computer games in children with different psychiatric disorders and normal controls. One hundred one children are recruited for the study (aged between 9 and 12 years). All participants played a motor-racing game on the computer for 1 hour. The TBAG form of the Stroop task was administered to all participants twice, before playing and immediately after playing the game. Participants with improved posttest scores, compared to their pretest scores, used the computer on average 0.67 +/- 1.1 hr/day, while the average administered was measured at 1.6 +/- 1.4 hr/day and 1.3 +/- 0.9 hr/day computer use for participants with worse or unaltered scores, respectively. According to the regression model, male gender, younger ages, duration of daily computer use, and ADHD inattention type were found to be independent risk factors for worsened posttest scores. Time spent playing computer games can exert a short-term effect on attention as measured by the Stroop test.

  5. Morphological processing with deficient phonological short-term memory.

    Science.gov (United States)

    Kavé, Gitit; Ze'ev, Hagit Bar; Lev, Anita

    2007-07-01

    This paper investigates the processing of Hebrew derivational morphology in an individual (S.E.) with deficient phonological short-term memory. In comparison to 10 age- and education-matched men, S.E. was impaired on digit span tasks and demonstrated no recency effect in word list recall. S.E. had low word retention span, but he exhibited phonological similarity and word length effects. His ability to make lexical decisions was intact. In a paired-associate test S.E. successfully learned semantically and morphologically related pairs but not phonologically related pairs, and his learning of nonwords was facilitated by the presence of Hebrew consonant roots. Semantic and morphological similarity enhanced immediate word recall. Results show that S.E. is capable of conducting morphological decomposition of Hebrew-derived words despite his phonological deficit, suggesting that transient maintenance of morphological constituents is independent of temporary storage and rehearsal of phonological codes, and that each is processed separately within short-term memory.

  6. A method for short term electricity spot price forecasting

    International Nuclear Information System (INIS)

    Koreneff, G.; Seppaelae, A.; Lehtonen, M.; Kekkonen, V.; Laitinen, E.; Haekli, J.; Antila, E.

    1998-01-01

    In Finland, the electricity market was de-regulated in November 1995. For the electricity purchase of power companies this has caused big changes, since the old tariff based contracts of bulk power supply have been replaced by negotiated bilateral short term contracts and by power purchase from the spot market. In the spot market, in turn, there are at the present two strong actors: The electricity exchange of Finland and the Nordic power pool which is run by the Swedish and Norwegian companies. Today, the power companies in Finland have short term trade with both of the electricity exchanges. The aim of this chapter is to present methods for spot price forecasting in the electricity exchange. The main focus is given to the Finnish circumstances. In the beginning of the presentation, the practices of the electricity exchange of Finland are described, and a brief presentation is given on the different contracts, or electricity products, available in the spot market. For comparison, the practices of the Nordic electricity exchange are also outlined. A time series technique for spot price forecasting is presented. The structure of the model is presented, and its validity is tested using real case data obtained from the Finnish power market. The spot price forecasting model is a part of a computer system for distribution energy management (DEM) in a de-regulated power market

  7. A method for short term electricity spot price forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Koreneff, G; Seppaelae, A; Lehtonen, M; Kekkonen, V [VTT Energy, Espoo (Finland); Laitinen, E; Haekli, J [Vaasa Univ. (Finland); Antila, E [ABB Transmit Oy (Finland)

    1998-08-01

    In Finland, the electricity market was de-regulated in November 1995. For the electricity purchase of power companies this has caused big changes, since the old tariff based contracts of bulk power supply have been replaced by negotiated bilateral short term contracts and by power purchase from the spot market. In the spot market, in turn, there are at the present two strong actors: The electricity exchange of Finland and the Nordic power pool which is run by the Swedish and Norwegian companies. Today, the power companies in Finland have short term trade with both of the electricity exchanges. The aim of this chapter is to present methods for spot price forecasting in the electricity exchange. The main focus is given to the Finnish circumstances. In the beginning of the presentation, the practices of the electricity exchange of Finland are described, and a brief presentation is given on the different contracts, or electricity products, available in the spot market. For comparison, the practices of the Nordic electricity exchange are also outlined. A time series technique for spot price forecasting is presented. The structure of the model is presented, and its validity is tested using real case data obtained from the Finnish power market. The spot price forecasting model is a part of a computer system for distribution energy management (DEM) in a de-regulated power market

  8. The IEA Model of Short-term Energy Security

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Ensuring energy security has been at the centre of the IEA mission since its inception, following the oil crises of the early 1970s. While the security of oil supplies remains important, contemporary energy security policies must address all energy sources and cover a comprehensive range of natural, economic and political risks that affect energy sources, infrastructures and services. In response to this challenge, the IEA is currently developing a Model Of Short-term Energy Security (MOSES) to evaluate the energy security risks and resilience capacities of its member countries. The current version of MOSES covers short-term security of supply for primary energy sources and secondary fuels among IEA countries. It also lays the foundation for analysis of vulnerabilities of electricity and end-use energy sectors. MOSES contains a novel approach to analysing energy security, which can be used to identify energy security priorities, as a starting point for national energy security assessments and to track the evolution of a country's energy security profile. By grouping together countries with similar 'energy security profiles', MOSES depicts the energy security landscape of IEA countries. By extending the MOSES methodology to electricity security and energy services in the future, the IEA aims to develop a comprehensive policy-relevant perspective on global energy security. This Working Paper is intended for readers who wish to explore the MOSES methodology in depth; there is also a brochure which provides an overview of the analysis and results.

  9. Short term assays for risk evaluate of α irradiation

    International Nuclear Information System (INIS)

    Fritsch, P.; Beauvallet, M.; Masse, R.; Lafuma, J.

    1979-01-01

    The genetic effects induced by α irradiation were examined using short term assays in Procaryotes and Eucaryotes. Irradiation was produced by 239 Pu dissolved as a DTPA equimolar complex in the culture medium. Induced mutagenesis was not observed with Ames' test or when test for ouabain resistance in CHO cells was used: GTG resistance and chromosome aberrations in Eucaryote cells were increased at dose rate exposure down to 5 R.day -1 . Until an optimal delivered dose, these two biological effects have shown a linear increase as a function of the dose. In our experimental conditions α irradiation has appeared to be much more lethal than mutagenic. Using lower dose rate, corresponding to 1 and 3 R a day we could also demonstrate a linear increase with dose of the induced TG resistant cells. Efficiency per unit dose was 3 to 5 times superior to what was observed at 5 R.day -1 . This phenomenon could correspond to an induced cell sensitivity, and clearly pointed out that for chronic and low delivered doses, informations deduced from flash or short term α exposure are not valuable

  10. Short-term cortical plasticity induced by conditioning pain modulation

    DEFF Research Database (Denmark)

    Egsgaard, Line Lindhardt; Buchgreitz, Line; Wang, Li

    2012-01-01

    To investigate the effects of homotopic and heterotopic conditioning pain modulation (CPM) on short-term cortical plasticity. Glutamate (tonic pain) or isotonic saline (sham) was injected in the upper trapezius (homotopic) and in the thenar (heterotopic) muscles. Intramuscular electrical stimulat......To investigate the effects of homotopic and heterotopic conditioning pain modulation (CPM) on short-term cortical plasticity. Glutamate (tonic pain) or isotonic saline (sham) was injected in the upper trapezius (homotopic) and in the thenar (heterotopic) muscles. Intramuscular electrical......, and after homotopic and heterotopic CPM versus control. Peak latencies at N100, P200, and P300 were extracted and the location/strength of corresponding dipole current sources and multiple dipoles were estimated. Homotopic CPM caused hypoalgesia (P = 0.032, 30.6% compared to baseline) to electrical...... stimulation. No cortical changes were found for homotopic CPM. A positive correlation at P200 between electrical pain threshold after tonic pain and the z coordinate after tonic pain (P = 0.032) was found for homotopic CPM. For heterotopic CPM, no significant hypoalgesia was found and a dipole shift of the P...

  11. A fuzzy inference model for short-term load forecasting

    International Nuclear Information System (INIS)

    Mamlook, Rustum; Badran, Omar; Abdulhadi, Emad

    2009-01-01

    This paper is concerned with the short-term load forecasting (STLF) in power system operations. It provides load prediction for generation scheduling and unit commitment decisions, and therefore precise load forecasting plays an important role in reducing the generation cost and the spinning reserve capacity. Short-term electricity demand forecasting (i.e., the prediction of hourly loads (demand)) is one of the most important tools by which an electric utility/company plans, dispatches the loading of generating units in order to meet system demand. The accuracy of the dispatching system, which is derived from the accuracy of the forecasting algorithm used, will determine the economics of the operation of the power system. The inaccuracy or large error in the forecast simply means that load matching is not optimized and consequently the generation and transmission systems are not being operated in an efficient manner. In the present study, a proposed methodology has been introduced to decrease the forecasted error and the processing time by using fuzzy logic controller on an hourly base. Therefore, it predicts the effect of different conditional parameters (i.e., weather, time, historical data, and random disturbances) on load forecasting in terms of fuzzy sets during the generation process. These parameters are chosen with respect to their priority and importance. The forecasted values obtained by fuzzy method were compared with the conventionally forecasted ones. The results showed that the STLF of the fuzzy implementation have more accuracy and better outcomes

  12. Critical protein GAPDH and its regulatory mechanisms in cancer cells

    International Nuclear Information System (INIS)

    Zhang, Jin-Ying; Zhang, Fan; Hong, Chao-Qun; Giuliano, Armando E.; Cui, Xiao-Jiang; Zhou, Guang-Ji; Zhang, Guo-Jun; Cui, Yu-Kun

    2015-01-01

    Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), initially identified as a glycolytic enzyme and considered as a housekeeping gene, is widely used as an internal control in experiments on proteins, mRNA, and DNA. However, emerging evidence indicates that GAPDH is implicated in diverse functions independent of its role in energy metabolism; the expression status of GAPDH is also deregulated in various cancer cells. One of the most common effects of GAPDH is its inconsistent role in the determination of cancer cell fate. Furthermore, studies have described GAPDH as a regulator of cell death; other studies have suggested that GAPDH participates in tumor progression and serves as a new therapeutic target. However, related regulatory mechanisms of its numerous cellular functions and deregulated expression levels remain unclear. GAPDH is tightly regulated at transcriptional and posttranscriptional levels, which are involved in the regulation of diverse GAPDH functions. Several cancer-related factors, such as insulin, hypoxia inducible factor-1 (HIF-1), p53, nitric oxide (NO), and acetylated histone, not only modulate GAPDH gene expression but also affect protein functions via common pathways. Moreover, posttranslational modifications (PTMs) occurring in GAPDH in cancer cells result in new activities unrelated to the original glycolytic function of GAPDH. In this review, recent findings related to GAPDH transcriptional regulation and PTMs are summarized. Mechanisms and pathways involved in GAPDH regulation and its different roles in cancer cells are also described

  13. Multiple post-transcriptional regulatory mechanisms in ferritin gene expression

    International Nuclear Information System (INIS)

    Mattia, E.; Den Blaauwen, J.; Van Renswoude, J.; Ashwell, G.

    1989-01-01

    The authors have investigated the mechanisms involved in the regulation of ferritin biosynthesis in K562 human erythroleukemia cells during prolonged exposure to iron. They show that, upon addition of hemin (an efficient iron donor) to the cell culture, the rate of ferritin biosynthesis reaches a maximum after a few hours and then decreases. During a 24-hr incubation with the iron donor the concentrations of total ferritin heavy (H) and light (L) subunit mRNAs rise 2- to 5-fold and 2- to 3-fold, respectively, over the control values, while the amount of the protein increases 10- to 30-fold. The hemin-induced increment in ferritin subunit mRNA is not prevented by deferoxamine, suggesting that it is not directly mediated by chelatable iron. In vitro nuclear transcription analyses performed on nuclei isolated from control cells and cells grown in the presence of hemin indicate that the rates of synthesis of H- and L-subunit mRNAs remain constant. They conclude that iron-induced ferritin biosynthesis is governed by multiple post-transcriptional regulatory mechanisms. They propose that exposure of cells to iron leads to stabilization of ferritin mRNAs, in addition to activation and translation of stored H-and L-subunit mRNAs

  14. A conserved regulatory mechanism in bifunctional biotin protein ligases.

    Science.gov (United States)

    Wang, Jingheng; Beckett, Dorothy

    2017-08-01

    Class II bifunctional biotin protein ligases (BirA), which catalyze post-translational biotinylation and repress transcription initiation, are broadly distributed in eubacteria and archaea. However, it is unclear if these proteins all share the same molecular mechanism of transcription regulation. In Escherichia coli the corepressor biotinoyl-5'-AMP (bio-5'-AMP), which is also the intermediate in biotin transfer, promotes operator binding and resulting transcription repression by enhancing BirA dimerization. Like E. coli BirA (EcBirA), Staphylococcus aureus, and Bacillus subtilis BirA (Sa and BsBirA) repress transcription in vivo in a biotin-dependent manner. In this work, sedimentation equilibrium measurements were performed to investigate the molecular basis of this biotin-responsive transcription regulation. The results reveal that, as observed for EcBirA, Sa, and BsBirA dimerization reactions are significantly enhanced by bio-5'-AMP binding. Thus, the molecular mechanism of the Biotin Regulatory System is conserved in the biotin repressors from these three organisms. © 2017 The Protein Society.

  15. The Unexplored Mechanisms and Regulatory Functions of Ribosomal Translocation

    Science.gov (United States)

    Alejo, Jose Luis

    In every cell, protein synthesis is carried out by the ribosome, a complex macromolecular RNA-protein assembly. Decades of structural and kinetic studies have increased our understanding of ribosome initiation, decoding, translocation and termination. Yet, the underlying mechanism of these fundamental processes has yet to be fully delineated. Hence, the molecular basis of regulation remains obscure. Here, single-molecule fluorescence methods are applied to decipher the mechanism and regulatory roles of the multi-step process of directional substrate translocation on the ribosome that accompanies every round of protein synthesis. In Chapter 1, single-molecule fluorescence resonance energy transfer (smFRET) is introduced as a tool for studying bacterial ribosome translocation. Chapter 2 details the experimental methods. In Chapter 3, the elongation factor G(EF-G)-catalyzed movement of substrates through the ribosome is examined from several perspectives or signals reporting on various degrees of freedom of ribosome dynamics. Two ribosomal states interconvert in the presence of EF-G(GDP), displaying novel head domain motions, until relocking takes place. In Chapter 4, in order to test if the mentioned fluctuations leading to relocking are correlated to the engagement of the P-site by the peptidyl-tRNA, the translocation of miscoded tRNAs is studied. Severe defects in the relocking stages of translocation reveal the correlation between this new stage of translocation and P-site tRNA engagement.

  16. A Spiking Working Memory Model Based on Hebbian Short-Term Potentiation

    Science.gov (United States)

    Fiebig, Florian

    2017-01-01

    A dominant theory of working memory (WM), referred to as the persistent activity hypothesis, holds that recurrently connected neural networks, presumably located in the prefrontal cortex, encode and maintain WM memory items through sustained elevated activity. Reexamination of experimental data has shown that prefrontal cortex activity in single units during delay periods is much more variable than predicted by such a theory and associated computational models. Alternative models of WM maintenance based on synaptic plasticity, such as short-term nonassociative (non-Hebbian) synaptic facilitation, have been suggested but cannot account for encoding of novel associations. Here we test the hypothesis that a recently identified fast-expressing form of Hebbian synaptic plasticity (associative short-term potentiation) is a possible mechanism for WM encoding and maintenance. Our simulations using a spiking neural network model of cortex reproduce a range of cognitive memory effects in the classical multi-item WM task of encoding and immediate free recall of word lists. Memory reactivation in the model occurs in discrete oscillatory bursts rather than as sustained activity. We relate dynamic network activity as well as key synaptic characteristics to electrophysiological measurements. Our findings support the hypothesis that fast Hebbian short-term potentiation is a key WM mechanism. SIGNIFICANCE STATEMENT Working memory (WM) is a key component of cognition. Hypotheses about the neural mechanism behind WM are currently under revision. Reflecting recent findings of fast Hebbian synaptic plasticity in cortex, we test whether a cortical spiking neural network model with such a mechanism can learn a multi-item WM task (word list learning). We show that our model can reproduce human cognitive phenomena and achieve comparable memory performance in both free and cued recall while being simultaneously compatible with experimental data on structure, connectivity, and

  17. A Spiking Working Memory Model Based on Hebbian Short-Term Potentiation.

    Science.gov (United States)

    Fiebig, Florian; Lansner, Anders

    2017-01-04

    A dominant theory of working memory (WM), referred to as the persistent activity hypothesis, holds that recurrently connected neural networks, presumably located in the prefrontal cortex, encode and maintain WM memory items through sustained elevated activity. Reexamination of experimental data has shown that prefrontal cortex activity in single units during delay periods is much more variable than predicted by such a theory and associated computational models. Alternative models of WM maintenance based on synaptic plasticity, such as short-term nonassociative (non-Hebbian) synaptic facilitation, have been suggested but cannot account for encoding of novel associations. Here we test the hypothesis that a recently identified fast-expressing form of Hebbian synaptic plasticity (associative short-term potentiation) is a possible mechanism for WM encoding and maintenance. Our simulations using a spiking neural network model of cortex reproduce a range of cognitive memory effects in the classical multi-item WM task of encoding and immediate free recall of word lists. Memory reactivation in the model occurs in discrete oscillatory bursts rather than as sustained activity. We relate dynamic network activity as well as key synaptic characteristics to electrophysiological measurements. Our findings support the hypothesis that fast Hebbian short-term potentiation is a key WM mechanism. Working memory (WM) is a key component of cognition. Hypotheses about the neural mechanism behind WM are currently under revision. Reflecting recent findings of fast Hebbian synaptic plasticity in cortex, we test whether a cortical spiking neural network model with such a mechanism can learn a multi-item WM task (word list learning). We show that our model can reproduce human cognitive phenomena and achieve comparable memory performance in both free and cued recall while being simultaneously compatible with experimental data on structure, connectivity, and neurophysiology of the underlying

  18. Short-Term Sleep Disturbance-Induced Stress Does not Affect Basal Pain Perception, but Does Delay Postsurgical Pain Recovery.

    Science.gov (United States)

    Wang, Po-Kai; Cao, Jing; Wang, Hongzhen; Liang, Lingli; Zhang, Jun; Lutz, Brianna Marie; Shieh, Kun-Ruey; Bekker, Alex; Tao, Yuan-Xiang

    2015-11-01

    Chronic sleep disturbance-induced stress is known to increase basal pain sensitivity. However, most surgical patients frequently report short-term sleep disturbance/deprivation during the pre- and postoperation periods and have normal pain perception presurgery. Whether this short-term sleep disturbance affects postsurgical pain is elusive. Here, we report that pre- or postexposure to rapid eye movement sleep disturbance (REMSD) for 6 hours daily for 3 consecutive days did not alter basal responses to mechanical, heat, and cold stimuli, but did delay recovery in incision-induced reductions in paw withdrawal threshold to mechanical stimulation and paw withdrawal latencies to heat and cold stimuli on the ipsilateral side of male or female rats. This short-term REMSD led to stress shown by an increase in swim immobility time, a decrease in sucrose consumption, and an increase in the level of corticosterone in serum. Blocking this stress via intrathecal RU38486 or bilateral adrenalectomy abolished REMSD-caused delay in recovery of incision-induced reductions in behavioral responses to mechanical, heat, and cold stimuli. Moreover, this short-term REMSD produced significant reductions in the levels of mu opioid receptor and kappa opioid receptor, but not Kv1.2, in the ipsilateral L4/5 spinal cord and dorsal root ganglia on day 9 after incision (but not after sham surgery). Our findings show that short-term sleep disturbance either pre- or postsurgery does not alter basal pain perception, but does exacerbate postsurgical pain hypersensitivity. The latter may be related to the reductions of mu and kappa opioid receptors in the spinal cord and dorsal root ganglia caused by REMSD plus incision. Prevention of short-term sleep disturbance may help recovery from postsurgical pain in patients. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  19. Poplar physiology and short-term biomass production

    Energy Technology Data Exchange (ETDEWEB)

    Reimer, P.; Lannoye, R. (Universite Libre de Bruxelles (Belgium). Lab. de Physiologie Vegetale)

    1990-01-01

    This program comprised the establishment, on biochemical and physiological basis, of specific screening tests for the rapid evaluation of poplar adaptation to environmental conditions. The resistance of chloroplasts to several major environmental stresses affecting biomass production (light, heat, cold and water stress) has been assessed in leaves of five poplar (Populus sp.) clones by in vivo chlorophyll fluorescence and oxygen production measurements. These two chloroplastic activities are correlated to the photosynthetic activity of the plant and respond immediately to any changes affecting the organization and the functioning of the photosynthetic apparatus, including regulatory mechanisms. Test clones were grown as cuttings in a .80 {times} .80m planting pattern. In addition, some plants were grown hydroponically in containers under a plastic roof in controlled conditions to test their behavior toward hydric (drought), light (shadow and overlight) and temperature (cold and warm) stresses. A specific data capture system has been developed to analyze clone resistance to environmental stresses. The results indicated considerable genetic variation in tolerance of poplar clones toward environmental stresses. The application of the in vivo fluorescence method and of the photoacoustic method appears to be an easy and rapid method to estimate the reaction of poplar clones against some stresses and thus for detecting plant species adapted to environmental stresses. 59 refs., 27 figs., 5 tabs.

  20. Analysis of short-term reactor cavity transient

    International Nuclear Information System (INIS)

    Cheng, T.C.; Fischer, S.R.

    1981-01-01

    Following the transient of a hypothetical loss-of-coolant accident (LOCA) in a nuclear reactor, peak pressures are reached within the first 0.03 s at different locations inside the reactor cavity. Due to the complicated multidimensional nature of the reactor cavity, the short-term analysis of the LOCA transient cannot be performed by using traditional containment codes, such as CONTEMPT. The advanced containment code, BEACON/MOD3, developed at the Idaho National Engineering Laboratory (INEL), can be adapted for such analysis. This code provides Eulerian, one and two-dimensional, nonhomogeneous, nonequilibrium flow modeling as well as lumped parameter, homogeneous, equilibrium flow modeling for the solution of two-component, two-phase flow problems. The purpose of this paper is to demonstrate the capability of the BEACON code to analyze complex containment geometry such as a reactor cavity

  1. Short-term memory loss associated with rosuvastatin.

    Science.gov (United States)

    Galatti, Laura; Polimeni, Giovanni; Salvo, Francesco; Romani, Marcello; Sessa, Aurelio; Spina, Edoardo

    2006-08-01

    Memory loss and cognitive impairment have been reported in the literature in association with several 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), but we found no published case reports associated with rosuvastatin. To our knowledge, this is the first reported case of rosuvastatin-related short-term memory loss. A 53-year-old Caucasian man with hypercholesterolemia experienced memory loss after being treated with rosuvastatin 10 mg/day. He had no other concomitant conditions or drug therapies. After discontinuation of rosuvastatin, the neuropsychiatric adverse reaction resolved gradually, suggesting a probable drug association. During the following year, the patient remained free from neuropsychiatric disturbances. Clinicians should be aware of possible adverse cognitive reactions during statin therapy, including rosuvastatin.

  2. Short-term contracts: Descending the career ladder

    Science.gov (United States)

    Griffin, Elizabeth

    2002-12-01

    Elizabeth Griffin brings a personal insight to the hurdles that women seeking a scientific career face, arguing that the only gender differences are those of attitude, tradition and style. The policy of employing some but not all academic researchers through short-term contracts is highly divisive, in that it creates a two-tier system not only of opportunities and expectations but also of personal worth and value. Far more women than men are trapped in these career cul-de-sacs, and a seriously large fraction is unable to stay in research until retirement. It is the employment policy that is at fault, not the potential of the researchers or the quality of their research.

  3. Short-Term Planning of Hybrid Power System

    Science.gov (United States)

    Knežević, Goran; Baus, Zoran; Nikolovski, Srete

    2016-07-01

    In this paper short-term planning algorithm for hybrid power system consist of different types of cascade hydropower plants (run-of-the river, pumped storage, conventional), thermal power plants (coal-fired power plants, combined cycle gas-fired power plants) and wind farms is presented. The optimization process provides a joint bid of the hybrid system, and thus making the operation schedule of hydro and thermal power plants, the operation condition of pumped-storage hydropower plants with the aim of maximizing profits on day ahead market, according to expected hourly electricity prices, the expected local water inflow in certain hydropower plants, and the expected production of electrical energy from the wind farm, taking into account previously contracted bilateral agreement for electricity generation. Optimization process is formulated as hourly-discretized mixed integer linear optimization problem. Optimization model is applied on the case study in order to show general features of the developed model.

  4. Short-term memory impairment and arithmetical ability.

    Science.gov (United States)

    Butterworth, B; Cipolotti, L; Warrington, E K

    1996-02-01

    We document the dissociation of preserved calculation skills in a patient with impaired auditory short-term memory. The patient (MRF) had a memory span of three digits. Furthermore, he showed rapid decrement in performance of single digits and letters with both auditory and visual presentation in the Brown-Peterson forgetting task. Analysis of his calculation skills revealed a normal ability to solve auditorily presented multidigit addition and subtraction problems such as 173 + 68 and to execute the Paced Auditory Serial Addition Task (Sampson, 1956, 1958; Gronwall, 1977). In addition, his performance on other tests, including arithmetic manipulation of natural numbers, decimals and fractions, approximation, magnitude, ratio, and percentage, appeared to be normal (Hitch, 1978b). It is argued that these findings require a revision of Baddeley and Hitch's (1974) concept of the function of working memory.

  5. Short-term Power Load Forecasting Based on Balanced KNN

    Science.gov (United States)

    Lv, Xianlong; Cheng, Xingong; YanShuang; Tang, Yan-mei

    2018-03-01

    To improve the accuracy of load forecasting, a short-term load forecasting model based on balanced KNN algorithm is proposed; According to the load characteristics, the historical data of massive power load are divided into scenes by the K-means algorithm; In view of unbalanced load scenes, the balanced KNN algorithm is proposed to classify the scene accurately; The local weighted linear regression algorithm is used to fitting and predict the load; Adopting the Apache Hadoop programming framework of cloud computing, the proposed algorithm model is parallelized and improved to enhance its ability of dealing with massive and high-dimension data. The analysis of the household electricity consumption data for a residential district is done by 23-nodes cloud computing cluster, and experimental results show that the load forecasting accuracy and execution time by the proposed model are the better than those of traditional forecasting algorithm.

  6. Short-term capture of the Earth-Moon system

    Science.gov (United States)

    Qi, Yi; de Ruiter, Anton

    2018-06-01

    In this paper, the short-term capture (STC) of an asteroid in the Earth-Moon system is proposed and investigated. First, the space condition of STC is analysed and five subsets of the feasible region are defined and discussed. Then, the time condition of STC is studied by parameter scanning in the Sun-Earth-Moon-asteroid restricted four-body problem. Numerical results indicate that there is a clear association between the distributions of the time probability of STC and the five subsets. Next, the influence of the Jacobi constant on STC is examined using the space and time probabilities of STC. Combining the space and time probabilities of STC, we propose a STC index to evaluate the probability of STC comprehensively. Finally, three potential STC asteroids are found and analysed.

  7. Short-term facilitation may stabilize parametric working memory trace

    Directory of Open Access Journals (Sweden)

    Vladimir eItskov

    2011-10-01

    Full Text Available Networks with continuous set of attractors are considered to be a paradigmatic model for parametric working memory, but require fine-tuning of connections and are thus structurally unstable. Here we analyzed the network with ring attractor, where connections are not perfectly tuned and the activity state therefore drifts in the absence of the stabilizing stimulus. We derive an analytical expression for the drift dynamics and conclude that the network cannot function as working memory for a period of several seconds, a typical delay time in monkey memory experiments. We propose that short-term synaptic facilitation in recurrent connections significantly improves the robustness of the model by slowing down the drift of activity bump. Extending the calculation of the drift velocity to network with synaptic facilitation, we conclude that facilitation can slow down the drift by a large factor, rendering the network suitable as a model of working memory.

  8. Emulating short-term synaptic dynamics with memristive devices

    Science.gov (United States)

    Berdan, Radu; Vasilaki, Eleni; Khiat, Ali; Indiveri, Giacomo; Serb, Alexandru; Prodromakis, Themistoklis

    2016-01-01

    Neuromorphic architectures offer great promise for achieving computation capacities beyond conventional Von Neumann machines. The essential elements for achieving this vision are highly scalable synaptic mimics that do not undermine biological fidelity. Here we demonstrate that single solid-state TiO2 memristors can exhibit non-associative plasticity phenomena observed in biological synapses, supported by their metastable memory state transition properties. We show that, contrary to conventional uses of solid-state memory, the existence of rate-limiting volatility is a key feature for capturing short-term synaptic dynamics. We also show how the temporal dynamics of our prototypes can be exploited to implement spatio-temporal computation, demonstrating the memristors full potential for building biophysically realistic neural processing systems.

  9. Short-Term Market Risks Implied by Weekly Options

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Fusari, Nicola; Todorov, Viktor

    a direct way to study volatility and jump risks. Unlike longer-dated options, they are largely insensitive to the risk of intertemporal shifts in the economic environment. Adopting a novel semi-nonparametric approach, we uncover variation in the negative jump tail risk which is not spanned by market......We study short-term market risks implied by weekly S&P 500 index options. The introduction of weekly options has dramatically shifted the maturity profile of traded options over the last five years, with a substantial proportion now having expiry within one week. Such short-dated options provide......" by the level of market volatility and elude standard asset pricing models....

  10. Panorama 2011: Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, A.

    2011-01-01

    2009 was a particularly bad year for the natural gas industry, with demand falling dramatically by 2.8% as a result of the world economic crisis. However, 2010 appears to have been a very positive year for the industry, with a sustained increase in production and trade. Increased economic activity, together with harsh winters and competitive gas prices are the reasons for the markets having rediscovered their buoyancy. Although the economic recovery has shown signs of fragility in OECD countries, global natural gas demand should continue to grow rapidly in the short-term, driven by consumption in developing countries, suggesting that the gas bubble will be reabsorbed faster than expected on the international markets. (author)

  11. The Delicate Analysis of Short-Term Load Forecasting

    Science.gov (United States)

    Song, Changwei; Zheng, Yuan

    2017-05-01

    This paper proposes a new method for short-term load forecasting based on the similar day method, correlation coefficient and Fast Fourier Transform (FFT) to achieve the precision analysis of load variation from three aspects (typical day, correlation coefficient, spectral analysis) and three dimensions (time dimension, industry dimensions, the main factors influencing the load characteristic such as national policies, regional economic, holidays, electricity and so on). First, the branch algorithm one-class-SVM is adopted to selection the typical day. Second, correlation coefficient method is used to obtain the direction and strength of the linear relationship between two random variables, which can reflect the influence caused by the customer macro policy and the scale of production to the electricity price. Third, Fourier transform residual error correction model is proposed to reflect the nature of load extracting from the residual error. Finally, simulation result indicates the validity and engineering practicability of the proposed method.

  12. Visual short-term memory for sequential arrays.

    Science.gov (United States)

    Kumar, Arjun; Jiang, Yuhong

    2005-04-01

    The capacity of visual short-term memory (VSTM) for a single visual display has been investigated in past research, but VSTM for multiple sequential arrays has been explored only recently. In this study, we investigate the capacity of VSTM across two sequential arrays separated by a variable stimulus onset asynchrony (SOA). VSTM for spatial locations (Experiment 1), colors (Experiments 2-4), orientations (Experiments 3 and 4), and conjunction of color and orientation (Experiment 4) were tested, with the SOA across the two sequential arrays varying from 100 to 1,500 msec. We find that VSTM for the trailing array is much better than VSTM for the leading array, but when averaged across the two arrays VSTM has a constant capacity independent of the SOA. We suggest that multiple displays compete for retention in VSTM and that separating information into two temporally discrete groups does not enhance the overall capacity of VSTM.

  13. Attention restores discrete items to visual short-term memory.

    Science.gov (United States)

    Murray, Alexandra M; Nobre, Anna C; Clark, Ian A; Cravo, André M; Stokes, Mark G

    2013-04-01

    When a memory is forgotten, is it lost forever? Our study shows that selective attention can restore forgotten items to visual short-term memory (VSTM). In our two experiments, all stimuli presented in a memory array were designed to be equally task relevant during encoding. During the retention interval, however, participants were sometimes given a cue predicting which of the memory items would be probed at the end of the delay. This shift in task relevance improved recall for that item. We found that this type of cuing improved recall for items that otherwise would have been irretrievable, providing critical evidence that attention can restore forgotten information to VSTM. Psychophysical modeling of memory performance has confirmed that restoration of information in VSTM increases the probability that the cued item is available for recall but does not improve the representational quality of the memory. We further suggest that attention can restore discrete items to VSTM.

  14. Implementing a short-term family support group.

    Science.gov (United States)

    Koontz, E; Cox, D; Hastings, S

    1991-05-01

    1. Although family involvement has been increasingly recognized as a vital component in the treatment and care of the mentally ill, little has been written about efforts to provide education and support to the families of patients hospitalized for short-term evaluation and treatment. 2. The family education and support group provided emotional support and critical information to increase family members' coping and problem solving abilities, and enabled them to return to a pre-crisis or higher level of functioning. 3. The family education and support group not only enhances the assessment and planning phases of the nursing process, but it also can serve as a useful intervention for strengthening the patient's major support system.

  15. Pro short-term procurement - U.S. utility

    International Nuclear Information System (INIS)

    Thompson, R.D.

    1990-01-01

    The author expresses the opinion that rather than focusing market discussions around short-term versus long-term procurement strategies, the parties need to be focusing on how long it is going to take to get to a predominantly market-based price both in uranium and enrichment. Long-term contracts are going to be around and will always be an important part of buyers' and sellers' strategies. It is evident that the annual term contract price renegotiations around the world are resulting in continually lower prices. When these price negotiations finally arrive in the range of the market price, a commodity market that resembles other energy commodity markets can be obtained

  16. Pro short-term procurement - Broker/trader

    International Nuclear Information System (INIS)

    Hoellen, E.E.

    1990-01-01

    The author presents his opinion on the issue of short-term versus long-term procurement of uranium and enrichment and the impact on reliability of supply. The progression of the market has been one of increasing commoditization. Utility buyers have moved towards purchasing uranium on the spot market and linking long-term contracts to spot-market pricing. There is some logic to the argument that utilities and the industry in general would be best served by this approach. Inventories would be worked off much more quickly, and unnecessary supply would be shut off until prices recovered to profitable levels. The result would be a healthier market with no detriment to the reliability of supply

  17. Mark I containment, short term program. Safety evaluation report

    International Nuclear Information System (INIS)

    1977-12-01

    Presented is a Safety Evaluation Report (SER) prepared by the Office of Nuclear Reactor Regulation addressing the Short Term Program (STP) reassessment of the containment systems of operating Boiler Water Reactor (BWR) facilities with the Mark I containment system design. The information presented in this SER establishes the basis for the NRC staff's conclusion that licensed Mark I BWR facilities can continue to operate safely, without undue risk to the health and safety of the public, during an interim period of approximately two years while a methodical, comprehensive Long Term Program (LTP) is conducted. This SER also provides one of the basic foundations for the NRC staff review of the Mark I containment systems for facilities not yet licensed for operation

  18. Short-term variability of Cyg X-1

    International Nuclear Information System (INIS)

    Oda, M.; Doi, K.; Ogawara, Y.

    1976-01-01

    The short-term X-ray variability distinguishes Cyg X-1, which is the most likely candidate for a black hole, from other X-ray sources. The present status of our knowledge on this short-term variation, mainly from the UHURU, the MIT and the GSFC observations, is reviewed. The nature of impulsive variations which compose the time variation exceeding the statistical fluctuation is discussed. There are indications that the energy spectrum of large pulses is harder than the average spectrum, or that the large pulses are the characteristics of the hard component of the spectrum if it is composed of two, soft and hard, components. Features of the variations may be partly simulated by the superposition of random shot-noise pulses with a fraction of a second duration. However, the autocorrelation analysis and the dynamic spectrum analysis indicate that the correlation lasts for several seconds and in the variation are buried some regularities which exhibit power concentrations in several frequency bands; 0.2-0.3, 0.4-0.5, 0.8, 1.2-1.5 Hz. There are several possible interpretations of these results in terms of; e.g. (a) a mixture of shot-noise pulses with two or more constant durations, (b) the shape of the basic shot-noise pulse, (c) bunching of the pulses, (d) superposition of wave-packets or temporal oscillations. But we have not yet reached any definite understandings in the nature of the variabilities. The substructure of the fluctuations on a time scale of milliseconds suggested by two investigations is also discussed. (Auth.)

  19. Short-term variability of CYG X-1

    International Nuclear Information System (INIS)

    Oda, M.; Doi, K.; Ogawara, Y.; Takagishi, K.; Wada, M.

    1975-01-01

    The short-term X-ray variability distinguishes Cyg X-1, which is the most likely candidate of the black hole, from other X-ray sources. Present status of our knowledge on this short-term variation mainly from the Uhuru, the MIT and the GSFC observations is reviewed. The nature of impulsive variations which compose the time variation exceeding the statistical fluctuation is discussed. There are indications that the energy spectrum of large pulses is harder than the average spectrum or the large pulses are the characteristics of the hard component of the spectrum if it is composed of two, soft and hard, components. Features of the variations may be partly simulated by the superposition of random short-noise pulses with a fraction of a second duration. However, the autocorrelation analysis and the dynamic spectrum analysis indicate that the correlation lasts for several seconds and in the variation buried are some regularities which exhibit power concentrations in several frequency bands; 0.2 -- 0.3, 0.4 -- 0.5, 0.8, 1.2 -- 1.5 Hz. There are several possible interpretation of these results in terms of: e.g. a) a mixture of short-noise pulses with two or more constant durations, b) the shape of the basic shot-noise pulse, c) bunching of the pulses, d) superposition of wave-packets or temporal oscillations. But we have not yet reached any definite understandings in the nature of the variabilities. The sub-structure of the fluctuations on a time scale of milli-second suggested by two investigations is also discussed. (auth.)

  20. Short-term Variability of Vitamin D-Related Biomarkers.

    Science.gov (United States)

    Lutsey, Pamela L; Parrinello, Christina M; Misialek, Jeffrey R; Hoofnagle, Andy N; Henderson, Clark M; Laha, Thomas J; Michos, Erin D; Eckfeldt, John H; Selvin, Elizabeth

    2016-12-01

    Quantifying the variability of biomarkers is important, as high within-person variability can lead to misclassification of individuals. Short-term variability of important markers of vitamin D metabolism is relatively unknown. A repeatability study was conducted in 160 Atherosclerosis Risk in Communities study participants (60% female, 28% black, mean age 76 years). Fasting serum was drawn at 2 time points, a median of 6 (range 3-13) weeks apart. Vitamin D binding protein (VDBP) and 25-hydroxyvitamin D [25(OH)D] were measured by LC-MS, fibroblast growth factor (FGF23) and parathyroid hormone (PTH) by enzyme-linked immunoassay, and calcium and phosphorus by Roche Cobas 6000. Free and bioavailable 25(OH)D were calculated. We calculated the within-person CV (CV W ), intraclass correlation coefficient (ICC), Spearman rank correlation coefficient (r), and percent reclassified. The CV W was lowest for calcium (2.0%), albumin (3.6%), 25(OH)D (6.9%), VDBP (7.0%) and phosphorus (7.6%); intermediate for free 25(OH)D (9.0%) and bioavailable 25(OH)D (9.9%); and highest for PTH (16.7%) and FGF23 (17.8%). Reclassification was highest for PTH, VDBP, and phosphorus (all 7.5%). The ICC and r were highest (≥0.80) for 25(OH)D, free 25(OH)D, bioavailable 25(OH)D and PTH, but somewhat lower (approximately 0.60-0.75) for the other biomarkers. Six-week short-term variability, as assessed by CV W , was quite low for VDBP, calcium and phosphorus, but fairly high for FGF23 and PTH. As such, multiple measurements of FGF23 and PTH may be needed to minimize misclassification. These results provide insight into the extent of potential misclassification of vitamin D markers in research and clinical settings. © 2016 American Association for Clinical Chemistry.

  1. Short-term risk of falling after cochlear implantation.

    Science.gov (United States)

    Stevens, Madelyn N; Baudhuin, Jacqueline E; Hullar, Timothy E

    2014-01-01

    Cochlear implantation is a highly effective intervention for hearing loss, but insertion of an implant into the cochlea is often accompanied by loss of residual hearing function. Sometimes, postoperative testing also shows loss of function in the semicircular canals or otolith organs. The effect of this loss on equilibrium, particularly in the short term following surgery, and the risk of falling due to this loss is unknown. We prospectively measured balance in 16 consecutive adult cochlear implant patients before and 2 weeks after surgery. Subjects stood on a foam pad with eyes closed, feet together and arms at the side. The length of time over which this posture could be maintained was recorded up to a maximum value of 30 s indicating normal performance. Ten of 16 subjects reached a maximal time on preoperative testing. Nine of 16 subjects lost balance function after surgery. Four of the 10 subjects with normal preoperative balance function lost function. Subjects older than the age of 60 were more likely to lose balance function than younger subjects. We used previously published values relating balance performance on foam to risk of falling to calculate the fall risk among our subjects. The relative risk of falling increased after surgery by more than threefold in some patients. Imbalance after cochlear implantation may be much more common, particularly in the short term, than previously appreciated. This imbalance is accompanied by an increased risk of falling in many patients. Careful preoperative counseling before implantation and postoperative therapeutic intervention to improve comfort and reduce the chance of falling may be warranted, particularly in patients at a risk for injuries from falls (level of evidence: 2b). © 2014 S. Karger AG, Basel.

  2. Pediatric laparoscopic sleeve gastrectomy in Turkey: Short-term results.

    Science.gov (United States)

    Ates, Ufuk; Ergun, Ergun; Gollu, Gulnur; Sozduyar, Sumeyye; Can, Ozlem Selvi; Yagmurlu, Aydin

    2018-05-01

    Obesity is one of the most rapidly increasing health problems in children. Laparoscopic sleeve gastrectomy (LSG) is one of the best treatment options and is feasible and safe in children. The aim of this study was to present the short-term results of a laparoscopic sleeve gastrectomy series in children. Children who underwent LSG in 2014-2017 were included in the study. Charts were investigated retrospectively and short-term weight loss was analyzed. Patients who had surgery in 2014-2017 were included in the study. There were six girls and two boys, and the median age was 15 years (range, 11-18 years). Mean weight was 159.25 ± 19.78 kg, and mean body mass index was 61.05 ± 8.5 kg/m 2 . Mean operation time was 70 min (range, 65-90 min), mean hospital stay was 5.1 days (range, 3-7 days), and mean follow up was 19.2 months (range, 1-43 months). Of these patients, five had hypertension and were under medication and two of these five also had hyperinsulinemia. One of the five children had Bardet-Biedl syndrome and one had bronchial asthma. After operation, medication was stopped in four of the eight children. At the time of writing, six patients were doing well without postoperative complications, or the need for reoperation. Even though the follow-up period was short and the number of patients was small, LSG was a feasible and promising surgical method for morbidly obese children. A multidisciplinary approach and lifelong behavior therapy are key steps for success. © 2018 Japan Pediatric Society.

  3. Human short-term spatial memory: precision predicts capacity.

    Science.gov (United States)

    Banta Lavenex, Pamela; Boujon, Valérie; Ndarugendamwo, Angélique; Lavenex, Pierre

    2015-03-01

    Here, we aimed to determine the capacity of human short-term memory for allocentric spatial information in a real-world setting. Young adults were tested on their ability to learn, on a trial-unique basis, and remember over a 1-min interval the location(s) of 1, 3, 5, or 7 illuminating pads, among 23 pads distributed in a 4m×4m arena surrounded by curtains on three sides. Participants had to walk to and touch the pads with their foot to illuminate the goal locations. In contrast to the predictions from classical slot models of working memory capacity limited to a fixed number of items, i.e., Miller's magical number 7 or Cowan's magical number 4, we found that the number of visited locations to find the goals was consistently about 1.6 times the number of goals, whereas the number of correct choices before erring and the number of errorless trials varied with memory load even when memory load was below the hypothetical memory capacity. In contrast to resource models of visual working memory, we found no evidence that memory resources were evenly distributed among unlimited numbers of items to be remembered. Instead, we found that memory for even one individual location was imprecise, and that memory performance for one location could be used to predict memory performance for multiple locations. Our findings are consistent with a theoretical model suggesting that the precision of the memory for individual locations might determine the capacity of human short-term memory for spatial information. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Working memory training improves visual short-term memory capacity.

    Science.gov (United States)

    Schwarb, Hillary; Nail, Jayde; Schumacher, Eric H

    2016-01-01

    Since antiquity, philosophers, theologians, and scientists have been interested in human memory. However, researchers today are still working to understand the capabilities, boundaries, and architecture. While the storage capabilities of long-term memory are seemingly unlimited (Bahrick, J Exp Psychol 113:1-2, 1984), working memory, or the ability to maintain and manipulate information held in memory, seems to have stringent capacity limits (e.g., Cowan, Behav Brain Sci 24:87-185, 2001). Individual differences, however, do exist and these differences can often predict performance on a wide variety of tasks (cf. Engle What is working-memory capacity? 297-314, 2001). Recently, researchers have promoted the enticing possibility that simple behavioral training can expand the limits of working memory which indeed may also lead to improvements on other cognitive processes as well (cf. Morrison and Chein, Psychol Bull Rev 18:46-60 2011). However, initial investigations across a wide variety of cognitive functions have produced mixed results regarding the transferability of training-related improvements. Across two experiments, the present research focuses on the benefit of working memory training on visual short-term memory capacity-a cognitive process that has received little attention in the training literature. Data reveal training-related improvement of global measures of visual short-term memory as well as of measures of the independent sub-processes that contribute to capacity (Awh et al., Psychol Sci 18(7):622-628, 2007). These results suggest that the ability to inhibit irrelevant information within and between trials is enhanced via n-back training allowing for selective improvement on untrained tasks. Additionally, we highlight a potential limitation of the standard adaptive training procedure and propose a modified design to ensure variability in the training environment.

  5. Neural networks engaged in short-term memory rehearsal are disrupted by irrelevant speech in human subjects.

    Science.gov (United States)

    Kopp, Franziska; Schröger, Erich; Lipka, Sigrid

    2004-01-02

    Rehearsal mechanisms in human short-term memory are increasingly understood in the light of both behavioural and neuroanatomical findings. However, little is known about the cooperation of participating brain structures and how such cooperations are affected when memory performance is disrupted. In this paper we use EEG coherence as a measure of synchronization to investigate rehearsal processes and their disruption by irrelevant speech in a delayed serial recall paradigm. Fronto-central and fronto-parietal theta (4-7.5 Hz), beta (13-20 Hz), and gamma (35-47 Hz) synchronizations are shown to be involved in our short-term memory task. Moreover, the impairment in serial recall due to irrelevant speech was preceded by a reduction of gamma band coherence. Results suggest that the irrelevant speech effect has its neural basis in the disruption of left-lateralized fronto-central networks. This stresses the importance of gamma band activity for short-term memory operations.

  6. Short-Term Synaptic Plasticity Regulation in Solution-Gated Indium-Gallium-Zinc-Oxide Electric-Double-Layer Transistors.

    Science.gov (United States)

    Wan, Chang Jin; Liu, Yang Hui; Zhu, Li Qiang; Feng, Ping; Shi, Yi; Wan, Qing

    2016-04-20

    In the biological nervous system, synaptic plasticity regulation is based on the modulation of ionic fluxes, and such regulation was regarded as the fundamental mechanism underlying memory and learning. Inspired by such biological strategies, indium-gallium-zinc-oxide (IGZO) electric-double-layer (EDL) transistors gated by aqueous solutions were proposed for synaptic behavior emulations. Short-term synaptic plasticity, such as paired-pulse facilitation, high-pass filtering, and orientation tuning, was experimentally emulated in these EDL transistors. Most importantly, we found that such short-term synaptic plasticity can be effectively regulated by alcohol (ethyl alcohol) and salt (potassium chloride) additives. Our results suggest that solution gated oxide-based EDL transistors could act as the platforms for short-term synaptic plasticity emulation.

  7. Time-resolved neuroimaging of visual short term memory consolidation by post-perceptual attention shifts.

    Science.gov (United States)

    Hecht, Marcus; Thiemann, Ulf; Freitag, Christine M; Bender, Stephan

    2016-01-15

    Post-perceptual cues can enhance visual short term memory encoding even after the offset of the visual stimulus. However, both the mechanisms by which the sensory stimulus characteristics are buffered as well as the mechanisms by which post-perceptual selective attention enhances short term memory encoding remain unclear. We analyzed late post-perceptual event-related potentials (ERPs) in visual change detection tasks (100ms stimulus duration) by high-resolution ERP analysis to elucidate these mechanisms. The effects of early and late auditory post-cues (300ms or 850ms after visual stimulus onset) as well as the effects of a visual interference stimulus were examined in 27 healthy right-handed adults. Focusing attention with post-perceptual cues at both latencies significantly improved memory performance, i.e. sensory stimulus characteristics were available for up to 850ms after stimulus presentation. Passive watching of the visual stimuli without auditory cue presentation evoked a slow negative wave (N700) over occipito-temporal visual areas. N700 was strongly reduced by a visual interference stimulus which impeded memory maintenance. In contrast, contralateral delay activity (CDA) still developed in this condition after the application of auditory post-cues and was thereby dissociated from N700. CDA and N700 seem to represent two different processes involved in short term memory encoding. While N700 could reflect visual post processing by automatic attention attraction, CDA may reflect the top-down process of searching selectively for the required information through post-perceptual attention. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. International Short-Term Countermeasures Survey - 2012 Update

    International Nuclear Information System (INIS)

    Ingham, Grant

    2013-01-01

    Nuclear emergency planning, preparedness, response, and management, in general, are essential elements of any country's nuclear power programme. Part of nuclear emergency planning and preparedness is the implementation of national emergency plans, including detailed procedures for the implementation of short-term countermeasures, before during, and after the release of radioactive substances. The timely and appropriate implementation of short-term countermeasures, such as sheltering, evacuation, and iodine prophylaxis, can, in case of a nuclear emergency with a release of radioactive material, considerably reduce the doses to the public in the vicinity of the nuclear installation. Although international guidelines exist, national procedures and practices may differ due to different national habits, cultural specificity, and societal needs. Different national procedures and practices may, however, in the case of a radioactive release affecting two neighbouring countries, lead to different decisions in the implementation of countermeasures. In order to better understand existing approaches and to facilitate the comparison of national practices, the NEA decided to launch a questionnaire on current practices regarding short-term countermeasures, updating a similar survey performed in 1994 and 2003, as countries' practices have since evolved and been modified. In 2012, it was decided to reevaluate the country approaches in light of the early lessons learnt from the Fukushima Daiichi NPP accident. The information collected may be used to understand the basis for decisions in various countries, and, if deemed appropriate, as a basis for international harmonisation. This may also assist member countries to explain to the public affected by an emergency why the decisions in neighbouring countries may vary. This report summarises the information given by member countries and includes nine sections to explore the different aspects, covering the following topics: member

  9. Posttraumatic Stress Disorder Disturbs Coronary Tone and Its Regulatory Mechanisms.

    Science.gov (United States)

    Lazuko, Svetlana S; Kuzhel, Olga P; Belyaeva, Lyudmila E; Manukhina, Eugenia B; Fred Downey, H; Tseilikman, Olga B; Komelkova, Maria V; Tseilikman, Vadim E

    2018-01-01

    Posttraumatic stress disorder (PTSD) is associated with myocardial injury, but changes in coronary regulatory mechanisms in PTSD have not been investigated. This study evaluated the effect of PTSD-inducing stress on coronary tone and its regulation by nitric oxide (NO) and voltage-gated K + channels. PTSD was induced by exposing rats to predator stress, 15 min daily for 10 days, followed by 14 stress-free days. Presence of PTSD was confirmed by the elevated plus-maze test. Coronary tone was evaluated from changes in coronary perfusion pressure of Langendorff isolated hearts. Predator stress induced significant decreases in coronary tone of isolated hearts and in blood pressure of intact rats. L-NAME, a non-selective NO synthase (NOS) inhibitor, but not S-MT, a selective iNOS inhibitor, and increased coronary tone of control rats. In PTSD rats, both L-NAME and S-MT increased coronary tone. Therefore, the stress-induced coronary vasodilation resulted from NO overproduction by both iNOS and eNOS. NOS induction was apparently due to systemic inflammation as evidenced by increased serum interleukin-1β and C-reactive protein in PTSD rats. Decreased corticosterone in PTSD rats may have contributed to inflammation and its effect on coronary tone. PTSD was also associated with voltage-gated K + channel dysfunction, which would have also reduced coronary tone.

  10. Density-dependence as a size-independent regulatory mechanism.

    Science.gov (United States)

    de Vladar, Harold P

    2006-01-21

    The growth function of populations is central in biomathematics. The main dogma is the existence of density-dependence mechanisms, which can be modelled with distinct functional forms that depend on the size of the population. One important class of regulatory functions is the theta-logistic, which generalizes the logistic equation. Using this model as a motivation, this paper introduces a simple dynamical reformulation that generalizes many growth functions. The reformulation consists of two equations, one for population size, and one for the growth rate. Furthermore, the model shows that although population is density-dependent, the dynamics of the growth rate does not depend either on population size, nor on the carrying capacity. Actually, the growth equation is uncoupled from the population size equation, and the model has only two parameters, a Malthusian parameter rho and a competition coefficient theta. Distinct sign combinations of these parameters reproduce not only the family of theta-logistics, but also the van Bertalanffy, Gompertz and Potential Growth equations, among other possibilities. It is also shown that, except for two critical points, there is a general size-scaling relation that includes those appearing in the most important allometric theories, including the recently proposed Metabolic Theory of Ecology. With this model, several issues of general interest are discussed such as the growth of animal population, extinctions, cell growth and allometry, and the effect of environment over a population.

  11. Toxin-antitoxin systems and regulatory mechanisms in Mycobacterium tuberculosis.

    Science.gov (United States)

    Slayden, Richard A; Dawson, Clinton C; Cummings, Jason E

    2018-06-01

    There has been a significant reduction in annual tuberculosis incidence since the World Health Organization declared tuberculosis a global health threat. However, treatment of M. tuberculosis infections requires lengthy multidrug therapeutic regimens to achieve a durable cure. The development of new drugs that are active against resistant strains and phenotypically diverse organisms continues to present the greatest challenge in the future. Numerous phylogenomic analyses have revealed that the Mtb genome encodes a significantly expanded repertoire of toxin-antitoxin (TA) loci that makes up the Mtb TA system. A TA loci is a two-gene operon encoding a 'toxin' protein that inhibits bacterial growth and an interacting 'antitoxin' partner that neutralizes the inhibitory activity of the toxin. The presence of multiple chromosomally encoded TA loci in Mtb raises important questions in regard to expansion, regulation and function. Thus, the functional roles of TA loci in Mtb pathogenesis have received considerable attention over the last decade. The cumulative results indicate that they are involved in regulating adaptive responses to stresses associated with the host environment and drug treatment. Here we review the TA families encoded in Mtb, discuss the duplication of TA loci in Mtb, regulatory mechanism of TA loci, and phenotypic heterogeneity and pathogenesis.

  12. Visual short-term memory load suppresses temporo-parietal junction activity and induces inattentional blindness.

    Science.gov (United States)

    Todd, J Jay; Fougnie, Daryl; Marois, René

    2005-12-01

    The right temporo-parietal junction (TPJ) is critical for stimulus-driven attention and visual awareness. Here we show that as the visual short-term memory (VSTM) load of a task increases, activity in this region is increasingly suppressed. Correspondingly, increasing VSTM load impairs the ability of subjects to consciously detect the presence of a novel, unexpected object in the visual field. These results not only demonstrate that VSTM load suppresses TPJ activity and induces inattentional blindness, but also offer a plausible neural mechanism for this perceptual deficit: suppression of the stimulus-driven attentional network.

  13. The Development of Automaticity in Short-Term Memory Search: Item-Response Learning and Category Learning

    Science.gov (United States)

    Cao, Rui; Nosofsky, Robert M.; Shiffrin, Richard M.

    2017-01-01

    In short-term-memory (STM)-search tasks, observers judge whether a test probe was present in a short list of study items. Here we investigated the long-term learning mechanisms that lead to the highly efficient STM-search performance observed under conditions of consistent-mapping (CM) training, in which targets and foils never switch roles across…

  14. Early Extinction after Fear Conditioning Yields a Context-Independent and Short-Term Suppression of Conditional Freezing in Rats

    Science.gov (United States)

    Chang, Chun-hui; Maren, Stephen

    2009-01-01

    Extinction of Pavlovian fear conditioning in rats is a useful model for therapeutic interventions in humans with anxiety disorders. Recently, we found that delivering extinction trials soon (15 min) after fear conditioning yields a short-term suppression of fear, but little long-term extinction. Here, we explored the possible mechanisms underlying…

  15. Short-Term International Internship Experiences for Future Teachers and Other Child Development Professionals

    Science.gov (United States)

    Miller, Kari Knutson; Gonzalez, Amber M.

    2016-01-01

    This paper examines outcomes associated with participation in short-term, international internship experiences. Results suggest short-term international internship experiences contribute to rich personal and professional development outcomes. Findings highlight participant challenges associated with initial internship experiences, professional…

  16. Use of Short-term Circulatory Support as a Bridge in Pediatric Heart Transplantation

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Canêo

    2015-01-01

    Full Text Available Background: Heart transplantation is considered the gold standard therapy for the advanced heart failure, but donor shortage, especially in pediatric patients, is the main limitation for this procedure, so most sick patients die while waiting for the procedure. Objective: To evaluate the use of short-term circulatory support as a bridge to transplantation in end-stage cardiomyopathy. Methods: Retrospective clinical study. Between January 2011 and December 2013, 40 patients with cardiomyopathy were admitted in our Pediatric Intensive Care Unit, with a mean age of 4.5 years. Twenty patients evolved during hospitalization with clinical deterioration and were classified as Intermacs 1 and 2. One patient died within 24 hours and 19 could be stabilized and were listed. They were divided into 2 groups: A, clinical support alone and B, implantation of short-term circulatory support as bridge to transplantation additionally to clinical therapy. Results: We used short-term mechanical circulatory support as a bridge to transplantation in 9. In group A (n=10, eight died waiting and 2 patients (20% were transplanted, but none was discharged. In group B (n=9, 6 patients (66.7% were transplanted and three were discharged.The mean support time was 21,8 days (6 to 984h. The mean transplant waiting list time was 33,8 days. Renal failure and sepsis were the main complication and causeof death in group A while neurologic complications were more prevalent en group B. Conclusion: Mechanical circulatory support increases survival on the pediatric heart transplantation waiting list in patients classified as Intermacs 1 and 2.

  17. Long-term associative learning predicts verbal short-term memory performance

    OpenAIRE

    Jones, Gary; Macken, Bill

    2017-01-01

    Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term...

  18. The regulatory mechanism in the U.S. lessons learned

    International Nuclear Information System (INIS)

    Roberts, T.M.

    1987-01-01

    The U.S. Nuclear Regulatory Commission is responsible for the regulation of the commercial uses of nuclear power in the United States in order to protect the public health and safety. The NRC has undertaken a number of initiatives to incorporate the experience gained from the over 25 years of commercial nuclear power plant operation. These initiatives are aimed at improving the regulatory structure currently in place by providing for a more predictable and stable regulatory environment and by more efficiently and effectively focusing the activities of utilities on the safe operation of their facilities. (author)

  19. Short-Term Effects of Midseason Coach Turnover on Team Performance in Soccer

    Science.gov (United States)

    Balduck, Anne-Line; Buelens, Marc; Philippaerts, Renaat

    2010-01-01

    The present study addressed the issue of short-term performance effects of midseason coach turnover in soccer. The goal of this study was to examine this effect on subsequent short-term team performance. The purposes of this study were to (a) examine whether midseason coach turnover improved results in the short term, and (b) examine how team…

  20. Short-term fasting alters cytochrome P450-mediated drug metabolism in humans

    NARCIS (Netherlands)

    Lammers, Laureen A.; Achterbergh, Roos; de Vries, Emmely M.; van Nierop, F. Samuel; Klümpen, Heinz-Josef; Soeters, Maarten R.; Boelen, Anita; Romijn, Johannes A.; Mathôt, Ron A. A.

    2015-01-01

    Experimental studies indicate that short-term fasting alters drug metabolism. However, the effects of short-term fasting on drug metabolism in humans need further investigation. Therefore, the aim of this study was to evaluate the effects of short-term fasting (36 h) on P450-mediated drug

  1. Periodization of Carbohydrate Intake: Short-Term Effect on Performance

    Directory of Open Access Journals (Sweden)

    Laurie-Anne Marquet

    2016-11-01

    Full Text Available Background: “Sleep-low” consists of a sequential periodization of carbohydrate (CHO availability—low glycogen recovery after “train high” glycogen-depleting interval training, followed by an overnight-fast and light intensity training (“train low” the following day. This strategy leads to an upregulation of several exercise-responsive signaling proteins, but the chronic effect on performance has received less attention. We investigated the effects of short-term exposure to this strategy on endurance performance. Methods: Following training familiarization, 11 trained cyclists were divided into two groups for a one-week intervention—one group implemented three cycles of periodized CHO intake to achieve the sleep-low strategy over six training sessions (SL, CHO intake: 6 g·kg−1·day−1, whereas the control group consumed an even distribution of CHO over the day (CON. Tests were a 2 h submaximal ride and a 20 km time trial. Results: SL improved their performance (mean: +3.2%; p < 0.05 compared to CON. The improvement was associated with a change in pacing strategy with higher power output during the second part of the test. No change in substrate utilization was observed after the training period for either group. Conclusion: Implementing the “sleep-low” strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism.

  2. Short term solar radiation forecasting: Island versus continental sites

    International Nuclear Information System (INIS)

    Boland, John; David, Mathieu; Lauret, Philippe

    2016-01-01

    Due its intermittency, the large-scale integration of solar energy into electricity grids is an issue and more specifically in an insular context. Thus, forecasting the output of solar energy is a key feature to efficiently manage the supply-demand balance. In this paper, three short term forecasting procedures are applied to island locations in order to see how they perform in situations that are potentially more volatile than continental locations. Two continental locations, one coastal and one inland are chosen for comparison. At the two time scales studied, ten minute and hourly, the island locations prove to be more difficult to forecast, as shown by larger forecast errors. It is found that the three methods, one purely statistical combining Fourier series plus linear ARMA models, one combining clear sky index models plus neural net models, and a third using a clear sky index plus ARMA, give similar forecasting results. It is also suggested that there is great potential of merging modelling approaches on different horizons. - Highlights: • Solar energy forecasting is more difficult for insular than continental sites. • Fourier series plus linear ARMA models are one forecasting method tested. • Clear sky index models plus neural net models are also tested. • Clear sky index models plus linear ARMA is also an option. • All three approaches have similar skill.

  3. Tactile short-term memory in sensory-deprived individuals.

    Science.gov (United States)

    Papagno, Costanza; Minniti, Giovanna; Mattavelli, Giulia C; Mantovan, Lara; Cecchetto, Carlo

    2017-02-01

    To verify whether loosing a sense or two has consequences on a spared sensory modality, namely touch, and whether these consequences depend on practice or are biologically determined, we investigated 13 deafblind participants, 16 deaf participants, 15 blind participants, and 13 matched normally sighted and hearing controls on a tactile short-term memory task, using checkerboard matrices of increasing length in which half of the squares were made up of a rough texture and half of a smooth one. Time of execution of a fixed matrix, number of correctly reproduced matrices, largest matrix correctly reproduced and tactile span were recorded. The three groups of sensory-deprived individuals did not differ in any measure, while blind and deaf participants outscored controls in all parameters except time of execution; the difference approached significance for deafblind people compared to controls only in one measure, namely correctly reproduced matrices. In blind and deafblind participants, performance negatively correlated with age of Braille acquisition, the older being the subject when acquiring Braille, the lower the performance, suggesting that practice plays a role. However, the fact that deaf participants, who did not share tactile experience, performed similarly to blind participants and significantly better than controls highlights that practice cannot be the only contribution to better tactile memory.

  4. Short-term memory stores organized by information domain.

    Science.gov (United States)

    Noyce, Abigail L; Cestero, Nishmar; Shinn-Cunningham, Barbara G; Somers, David C

    2016-04-01

    Vision and audition have complementary affinities, with vision excelling in spatial resolution and audition excelling in temporal resolution. Here, we investigated the relationships among the visual and auditory modalities and spatial and temporal short-term memory (STM) using change detection tasks. We created short sequences of visual or auditory items, such that each item within a sequence arose at a unique spatial location at a unique time. On each trial, two successive sequences were presented; subjects attended to either space (the sequence of locations) or time (the sequence of inter item intervals) and reported whether the patterns of locations or intervals were identical. Each subject completed blocks of unimodal trials (both sequences presented in the same modality) and crossmodal trials (Sequence 1 visual, Sequence 2 auditory, or vice versa) for both spatial and temporal tasks. We found a strong interaction between modality and task: Spatial performance was best on unimodal visual trials, whereas temporal performance was best on unimodal auditory trials. The order of modalities on crossmodal trials also mattered, suggesting that perceptual fidelity at encoding is critical to STM. Critically, no cost was attributable to crossmodal comparison: In both tasks, performance on crossmodal trials was as good as or better than on the weaker unimodal trials. STM representations of space and time can guide change detection in either the visual or the auditory modality, suggesting that the temporal or spatial organization of STM may supersede sensory-specific organization.

  5. Short-term economics of virtual power plants

    International Nuclear Information System (INIS)

    Kok, J.K.

    2009-08-01

    The Virtual Power Plant (VPP) has gained an increasing interest over the last few years. A VPP is a flexible representation of a portfolio of Distributed Energy Resources (DER: distributed generation, demand response and electricity storage). One of the key activities of a VPP is the delivery of (near-)real-time balancing services. In order to operate such a (near-)real-time coordination activity optimally, the VPP needs to maintain a dynamic merit-order list of all DER participating in the VPP. In order to make optimal decisions based on this list, the merit order needs to be based on the true marginal cost (or marginal benefit in case of demand response) of the individual DER units. The marginal electricity costs of most types of DER are highly dependent on local context and, hence, change over time. From analysis of the short-term bid strategies of various DER units, the existence of a bid strategy spectrum becomes clear. On one end of the spectrum, bidding strategies are based straightforwardly on true marginal cost or benefit. Further along the spectrum, optimal bidding strategies become less dependent on marginal cost levels and more on the price dynamics in the (VPP) market context. These results are relevant for VPP operations both from business and technical perspectives.

  6. Short-term static corrosion tests in lead-bismuth

    Science.gov (United States)

    Soler Crespo, L.; Martín Muñoz, F. J.; Gómez Briceño, D.

    2001-07-01

    Martensitic steels have been proposed to be used as structural materials and as spallation target window in hybrid systems devoted to the transmutation of radioactive waste of long life and high activity. However, their compatibility with lead-bismuth in the operating conditions of these systems depends on the existence of a protective layer such as an oxide film. The feasibility of forming and maintaining an oxide layer or maintaining a pre-oxidised one has been studied. Martensitic steel F82Hmod. (8% Cr) has been tested in lead-bismuth under static and isothermal conditions at 400°C and 600°C. In order to study the first stages of the interaction between the steel and the eutectic, short-term tests (100 and 665 h) have been carried out. Pre-oxidised and as-received samples have been tested in atmospheres with different oxidant potential. For low oxygen concentration in lead-bismuth due to unexpected oxygen consumption in the experimental device, dissolution of as-received F82Hmod. occurs and pre-oxidation does not prevent the material dissolution. For high oxygen concentration, the pre-oxidation layer seems to improve the feasibility of protecting stainless steels controlling the oxygen potential of lead-bismuth with a gas phase.

  7. Short-term static corrosion tests in lead-bismuth

    International Nuclear Information System (INIS)

    Soler Crespo, L.; Martin Munoz, F.J.; Gomez Briceno, D.

    2001-01-01

    Martensitic steels have been proposed to be used as structural materials and as spallation target window in hybrid systems devoted to the transmutation of radioactive waste of long life and high activity. However, their compatibility with lead-bismuth in the operating conditions of these systems depends on the existence of a protective layer such as an oxide film. The feasibility of forming and maintaining an oxide layer or maintaining a pre-oxidised one has been studied. Martensitic steel F82Hmod. (8% Cr) has been tested in lead-bismuth under static and isothermal conditions at 400 o C and 600 o C. In order to study the first stages of the interaction between the steel and the eutectic, short-term tests (100 and 665 h) have been carried out. Pre-oxidised and as-received samples have been tested in atmospheres with different oxidant potential. For low oxygen concentration in lead-bismuth due to unexpected oxygen consumption in the experimental device, dissolution of as-received F82Hmod. occurs and pre-oxidation does not prevent the material dissolution. For high oxygen concentration, the pre-oxidation layer seems to improve the feasibility of protecting stainless steels controlling the oxygen potential of lead-bismuth with a gas phase

  8. Slave systems in verbal short-term memory.

    Science.gov (United States)

    Caplan, David; Waters, Gloria; Howard, David

    2012-01-01

    The model of performance in short-term memory (STM) tasks that has been most influential in cognitive neuropsychological work on deficits of STM is the "working memory" model mainly associated with the work of Alan Baddeley and his colleagues. This paper reviews the model. We examine the development of this theory in studies that account for STM performances in normal (non-brain-damaged) individuals, and then review the application of this theory to neuropsychological cases and specifications, modifications, and extensions of the theory that have been suggested on the basis of these cases. Our approach is to identify the major phenomena that have been discussed and to examine selected papers dealing with those phenomena in some detail. The main contribution is a review of the WM model that includes both normative and neuropsychological data. We conclude that the WM model has many inconsistencies and empirical inadequacies, and that cognitive neuropsychologists might benefit from considering other models when they attempt to describe and explain patients' performances on STM tasks.

  9. A New Strategy for Short-Term Load Forecasting

    Directory of Open Access Journals (Sweden)

    Yi Yang

    2013-01-01

    Full Text Available Electricity is a special energy which is hard to store, so the electricity demand forecasting remains an important problem. Accurate short-term load forecasting (STLF plays a vital role in power systems because it is the essential part of power system planning and operation, and it is also fundamental in many applications. Considering that an individual forecasting model usually cannot work very well for STLF, a hybrid model based on the seasonal ARIMA model and BP neural network is presented in this paper to improve the forecasting accuracy. Firstly the seasonal ARIMA model is adopted to forecast the electric load demand day ahead; then, by using the residual load demand series obtained in this forecasting process as the original series, the follow-up residual series is forecasted by BP neural network; finally, by summing up the forecasted residual series and the forecasted load demand series got by seasonal ARIMA model, the final load demand forecasting series is obtained. Case studies show that the new strategy is quite useful to improve the accuracy of STLF.

  10. Rhythmic Haptic Stimuli Improve Short-Term Attention.

    Science.gov (United States)

    Zhang, Shusheng; Wang, Dangxiao; Afzal, Naqash; Zhang, Yuru; Wu, Ruilin

    2016-01-01

    Brainwave entrainment using rhythmic visual and/or auditory stimulation has shown its efficacy in modulating neural activities and cognitive ability. In the presented study, we aim to investigate whether rhythmic haptic stimulation could enhance short-term attention. An experiment with sensorimotor rhythm (SMR) increasing protocol was performed in which participants were presented sinusoidal vibrotactile stimulus of 15 Hz on their palm. Test of Variables of Attention (T.O.V.A.) was performed before and after the stimulating session. Electroencephalograph (EEG) was recorded across the stimulating session and the two attention test sessions. SMR band power manifested a significant increase after stimulation. Results of T.O.V.A. tests indicated an improvement in the attention of participants who had received the stimulation compared to the control group who had not received the stimulation. The D prime score of T.O.V.A. reveals that participants performed better in perceptual sensitivity and sustaining attention level compared to their baseline performance before the stimulating session. These findings highlight the potential value of using haptics-based brainwave entrainment for cognitive training.

  11. Short term forecasting of petroleum product demand in France

    International Nuclear Information System (INIS)

    Cadren, M.

    1998-01-01

    The analysis of petroleum product demand became a privileged thrust of research following the modifications in terms of structure and level of the petroleum markets since eighties. The greatest importance to econometrics models of Energy demand, joint works about nonstationary data, explained the development of error-correction models and the co-integration. In this context, the short term econometrics modelling of petroleum product demand does not only focus on forecasts but also on the measure of the gain acquired from using error-correction techniques and co-integration. It's filling to take the influence of technical improvement and environment pressures into account in econometrics modelling of petroleum products demand. The first part presents the evolution of Energy Demand in France and more particularly the petroleum product demand since 1986. The objective is to determine the main characteristics of each product, which will help us to analyse and validate the econometrics models. The second part focus on the recent developments in times series modelling. We study the problem of nonstationary data and expose different unit root tests. We examine the main approaches to univariate and multivariate modelling with nonstationary data and distinguish the forecasts of the latter's. The third part is intended to applications; its objective is to illustrate the theoretic developments of the second part with a comparison between the performances of different approaches (approach Box and Jenkins, Johansen approach's and structural approach). The models will be applied to the main French petroleum market. The observed asymmetrical demand behaviour is also considered. (author)

  12. Short-term memory stores organized by information domain

    Science.gov (United States)

    Noyce, Abigail L.; Cestero, Nishmar; Shinn-Cunningham, Barbara G.; Somers, David C.

    2016-01-01

    Vision and audition have complementary affinities, with vision excelling in spatial resolution and audition excelling in temporal resolution. Here, we investigate the relationships among visual and auditory modalities and spatial and temporal short-term memory (STM) using change detection tasks. We created short sequences of visual or auditory items, such that each item within a sequence arose at a unique spatial location at a unique time. On each trial, two successive sequences were presented; subjects attended to either space (the sequence of locations), or time (the sequence of inter-item intervals), and reported whether the patterns of locations or intervals were identical. Each subject completed blocks of unimodal trials (both sequences presented in the same modality) and crossmodal trials (sequence 1 visual and sequence 2 auditory, or vice versa) for both spatial and temporal tasks. We found a strong interaction between modality and task: spatial performance was best on unimodal visual trials, while temporal performance was best on unimodal auditory trials. The order of modalities on crossmodal trials also mattered, suggesting that perceptual fidelity at encoding is critical to STM. Critically, there was no cost attributable to crossmodal comparison: in both tasks, performance on crossmodal trials was as good or better than on the weaker unimodal trials. STM representations of space and time can guide change detection in either the visual or the auditory modality, suggesting that temporal or spatial organization of STM may supersede sensory-specific organization. PMID:26791231

  13. Transcatheter arterial embolization for hepatoma; I. Short-term evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Heung Suk; Koh, Byung Hee; Cho, On Koo; Hahm, Chang Kok; Rhee, Jong Chul; Lee, Min Ho; Kee, Choon Suhk [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1985-12-15

    Anticancer effect and complications were evaluated after transcatheter arterial embolization (TAE) in 12 patients with hepatocellular carcinoma until 2 weeks and 4 weeks after TAE, respectively. The results were as follows; 1. Serum alpha-fetoprotein value decreased in 7 out of 9 patients with high value prior to TAE. 2. Loss of enhancement and better definition on enhanced computed tomography (CT) were seen in the tumors in all caes, and low density areas in 9/10.Gas bubbles were seen in low-density areas in 4/10 and high density areas caused by lipiodol in 6/10. 3. Post-embolization syndrome was developed in most patients but improved clinically within a week after TAE. 4. On laboratory examination, impairment of liver function was developed in most patients but improved within 4 weeks after TAE. 5. Complications on CT included splenic infarction and thickening of wall of the gallbladder, which didn't require specific treatment. The authors conclude that TAE for hepatocellular carcinoma reveals apparent anticancer effect on short-term evaluation, and resultant complications are transient and improved by conservative treatment.

  14. Transcatheter arterial embolization for hepatoma; I. Short-term evaluation

    International Nuclear Information System (INIS)

    Seo, Heung Suk; Koh, Byung Hee; Cho, On Koo; Hahm, Chang Kok; Rhee, Jong Chul; Lee, Min Ho; Kee, Choon Suhk

    1985-01-01

    Anticancer effect and complications were evaluated after transcatheter arterial embolization (TAE) in 12 patients with hepatocellular carcinoma until 2 weeks and 4 weeks after TAE, respectively. The results were as follows; 1. Serum alpha-fetoprotein value decreased in 7 out of 9 patients with high value prior to TAE. 2. Loss of enhancement and better definition on enhanced computed tomography (CT) were seen in the tumors in all caes, and low density areas in 9/10.Gas bubbles were seen in low-density areas in 4/10 and high density areas caused by lipiodol in 6/10. 3. Post-embolization syndrome was developed in most patients but improved clinically within a week after TAE. 4. On laboratory examination, impairment of liver function was developed in most patients but improved within 4 weeks after TAE. 5. Complications on CT included splenic infarction and thickening of wall of the gallbladder, which didn't require specific treatment. The authors conclude that TAE for hepatocellular carcinoma reveals apparent anticancer effect on short-term evaluation, and resultant complications are transient and improved by conservative treatment

  15. Slave systems in verbal short-term memory

    Science.gov (United States)

    Caplan, David; Waters, Gloria; Howard, David

    2013-01-01

    Background The model of performance in short-term memory (STM) tasks that has been most influential in cognitive neuropsychological work on deficits of STM is the “working memory” model mainly associated with the work of Alan Baddeley and his colleagues. Aim This paper reviews the model. We examine the development of this theory in studies that account for STM performances in normal (non-brain-damaged) individuals, and then review the application of this theory to neuropsychological cases and specifications, modifications, and extensions of the theory that have been suggested on the basis of these cases. Our approach is to identify the major phenomena that have been discussed and to examine selected papers dealing with those phenomena in some detail. Main Contribution The main contribution is a review of the WM model that includes both normative and neuropsychological data. Conclusions We conclude that the WM model has many inconsistencies and empirical inadequacies, and that cognitive neuropsychologists might benefit from considering other models when they attempt to describe and explain patients’ performances on STM tasks. PMID:24347786

  16. Short Term Memory, Working Memory, and Syntactic Comprehension in Aphasia

    Science.gov (United States)

    Caplan, David; Michaud, Jennifer; Hufford, Rebecca

    2013-01-01

    Sixty one people with aphasia were tested on ten tests of short term memory (STM) and for the ability to use syntactic structure to determine the meanings of eleven types of sentences in three tasks – object manipulation, picture matching and picture matching with self-paced listening. Multilevel models showed relationships between measures of the ability to retain and manipulate item and order information in STM and accuracy and RT, and a greater relationship between these STM measures and accuracy and RT for several more complex sentence types in individual tasks. There were no effects of measures of STM that reflect the use of phonological codes or rehearsal on comprehension. There was only one effect of STM measures on self-paced listening times. There were double dissociations between performance on STM and individual comprehension tasks, indicating that normal STM is not necessary to perform normally on these tasks. The results are most easily related to the view that STM plays a facilitatory role in supporting the use of the products of the comprehension process to accomplish operations related to tasks. PMID:23865692

  17. Short term load forecasting using neuro-fuzzy networks

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, M.; Hassan, A. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Martinez, D. [Black Hills Power and Light, Rapid City, SD (United States)

    2005-07-01

    Details of a neuro-fuzzy network-based short term load forecasting system for power utilities were presented. The fuzzy logic controller was used to fuzzify inputs representing historical temperature and load curves. The fuzzified inputs were then used to develop the fuzzy rules matrix. Output membership function values were determined by evaluating the fuzzified inputs with the fuzzy rules. Output membership function values were used as inputs for the neural network portion of the system. The training process used a back propagation gradient descent algorithm to adjust the weight values of the neural network in order to reduce the error between the neural network output and the desired output. The neural network was then used to predict future load values. Sample data were taken from a local power company's daily load curve to validate the system. A 10 per cent forecast error was introduced in the temperature values to determine the effect on load prediction. Results of the study suggest that the combined use of fuzzy logic and neural networks provide greater accuracy than studies where either approach is used alone. 6 refs., 6 figs.

  18. An information capacity limitation of visual short-term memory.

    Science.gov (United States)

    Sewell, David K; Lilburn, Simon D; Smith, Philip L

    2014-12-01

    Research suggests that visual short-term memory (VSTM) has both an item capacity, of around 4 items, and an information capacity. We characterize the information capacity limits of VSTM using a task in which observers discriminated the orientation of a single probed item in displays consisting of 1, 2, 3, or 4 orthogonally oriented Gabor patch stimuli that were presented in noise for 50 ms, 100 ms, 150 ms, or 200 ms. The observed capacity limitations are well described by a sample-size model, which predicts invariance of ∑(i)(d'(i))² for displays of different sizes and linearity of (d'(i))² for displays of different durations. Performance was the same for simultaneous and sequentially presented displays, which implicates VSTM as the locus of the observed invariance and rules out explanations that ascribe it to divided attention or stimulus encoding. The invariance of ∑(i)(d'(i))² is predicted by the competitive interaction theory of Smith and Sewell (2013), which attributes it to the normalization of VSTM traces strengths arising from competition among stimuli entering VSTM. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  19. Visual short term memory related brain activity predicts mathematical abilities.

    Science.gov (United States)

    Boulet-Craig, Aubrée; Robaey, Philippe; Lacourse, Karine; Jerbi, Karim; Oswald, Victor; Krajinovic, Maja; Laverdière, Caroline; Sinnett, Daniel; Jolicoeur, Pierre; Lippé, Sarah

    2017-07-01

    Previous research suggests visual short-term memory (VSTM) capacity and mathematical abilities are significantly related. Moreover, both processes activate similar brain regions within the parietal cortex, in particular, the intraparietal sulcus; however, it is still unclear whether the neuronal underpinnings of VSTM directly correlate with mathematical operation and reasoning abilities. The main objective was to investigate the association between parieto-occipital brain activity during the retention period of a VSTM task and performance in mathematics. The authors measured mathematical abilities and VSTM capacity as well as brain activity during memory maintenance using magnetoencephalography (MEG) in 19 healthy adult participants. Event-related magnetic fields (ERFs) were computed on the MEG data. Linear regressions were used to estimate the strength of the relation between VSTM related brain activity and mathematical abilities. The amplitude of parieto-occipital cerebral activity during the retention of visual information was related to performance in 2 standardized mathematical tasks: mathematical reasoning and calculation fluency. The findings show that brain activity during retention period of a VSTM task is associated with mathematical abilities. Contributions of VSTM processes to numerical cognition should be considered in cognitive interventions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Short-term ensemble radar rainfall forecasts for hydrological applications

    Science.gov (United States)

    Codo de Oliveira, M.; Rico-Ramirez, M. A.

    2016-12-01

    Flooding is a very common natural disaster around the world, putting local population and economy at risk. Forecasting floods several hours ahead and issuing warnings are of main importance to permit proper response in emergency situations. However, it is important to know the uncertainties related to the rainfall forecasting in order to produce more reliable forecasts. Nowcasting models (short-term rainfall forecasts) are able to produce high spatial and temporal resolution predictions that are useful in hydrological applications. Nonetheless, they are subject to uncertainties mainly due to the nowcasting model used, errors in radar rainfall estimation, temporal development of the velocity field and to the fact that precipitation processes such as growth and decay are not taken into account. In this study an ensemble generation scheme using rain gauge data as a reference to estimate radars errors is used to produce forecasts with up to 3h lead-time. The ensembles try to assess in a realistic way the residual uncertainties that remain even after correction algorithms are applied in the radar data. The ensembles produced are compered to a stochastic ensemble generator. Furthermore, the rainfall forecast output was used as an input in a hydrodynamic sewer network model and also in hydrological model for catchments of different sizes in north England. A comparative analysis was carried of how was carried out to assess how the radar uncertainties propagate into these models. The first named author is grateful to CAPES - Ciencia sem Fronteiras for funding this PhD research.

  1. Grouping and binding in visual short-term memory.

    Science.gov (United States)

    Quinlan, Philip T; Cohen, Dale J

    2012-09-01

    Findings of 2 experiments are reported that challenge the current understanding of visual short-term memory (VSTM). In both experiments, a single study display, containing 6 colored shapes, was presented briefly and then probed with a single colored shape. At stake is how VSTM retains a record of different objects that share common features: In the 1st experiment, 2 study items sometimes shared a common feature (either a shape or a color). The data revealed a color sharing effect, in which memory was much better for items that shared a common color than for items that did not. The 2nd experiment showed that the size of the color sharing effect depended on whether a single pair of items shared a common color or whether 2 pairs of items were so defined-memory for all items improved when 2 color groups were presented. In explaining performance, an account is advanced in which items compete for a fixed number of slots, but then memory recall for any given stored item is prone to error. A critical assumption is that items that share a common color are stored together in a slot as a chunk. The evidence provides further support for the idea that principles of perceptual organization may determine the manner in which items are stored in VSTM. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  2. Implications of short-term financial outlook for Canadian producers

    International Nuclear Information System (INIS)

    Shiry, J.

    1997-01-01

    The short-term outlook for the Western Canadian natural gas industry was reviewed. Based on the dramatic growth in the demand for gas, and the explosive growth of the industry in response to export opportunities, the outlook for the remainder of this decade remains good, notwithstanding low internal returns, below-average returns on equity, and increased competition for U.S. markets. The competition will come from offshore wells in the US Gulf, from offshore wells of Sable Island, and from offshore wells in the Gulf of Mexico. Despite the increasing sources of supply gas prices are actually expected to improve slightly in 1997 and beyond, giving rise to cautious optimism. Nevertheless, more favorable tax treatment is urgently required to head off the likelihood of investment dollars moving to Africa, the Middle East, South America, and most especially China and Russia. Once those countries open up for business in the not-too-distant future, the likelihood of them offering substantially better tax treatment than what is available in Canada could do serious damage to domestic gas industry development. 12 figs

  3. Biochemical and hematologic changes after short-term space flight

    Science.gov (United States)

    Leach, C. S.

    1992-01-01

    Clinical laboratory data from blood samples obtained from astronauts before and after 28 flights (average duration = 6 days) of the Space Shuttle were analyzed by the paired t-test and the Wilcoxon signed-rank test and compared with data from the Skylab flights (duration approximately 28, 59, and 84 days). Angiotensin I and aldosterone were elevated immediately after short-term space flights, but the response of angiotensin I was delayed after Skylab flights. Serum calcium was not elevated after Shuttle flights, but magnesium and uric acid decreased after both Shuttle and Skylab. Creatine phosphokinase in serum was reduced after Shuttle but not Skylab flights, probably because exercises to prevent deconditioning were not performed on the Shuttle. Total cholesterol was unchanged after Shuttle flights, but low density lipoprotein cholesterol increased and high density lipoprotein cholesterol decreased. The concentration of red blood cells was elevated after Shuttle flights and reduced after Skylab flights. Reticulocyte count was decreased after both short- and long-term flights, indicating that a reduction in red blood cell mass is probably more closely related to suppression of red cell production than to an increase in destruction of erythrocytes. Serum ferritin and number of platelets were also elevated after Shuttle flights. In determining the reasons for postflight differences between the shorter and longer flights, it is important to consider not only duration but also countermeasures, differences between spacecraft, and procedures for landing and egress.

  4. Audiovisual integration facilitates monkeys' short-term memory.

    Science.gov (United States)

    Bigelow, James; Poremba, Amy

    2016-07-01

    Many human behaviors are known to benefit from audiovisual integration, including language and communication, recognizing individuals, social decision making, and memory. Exceptionally little is known about the contributions of audiovisual integration to behavior in other primates. The current experiment investigated whether short-term memory in nonhuman primates is facilitated by the audiovisual presentation format. Three macaque monkeys that had previously learned an auditory delayed matching-to-sample (DMS) task were trained to perform a similar visual task, after which they were tested with a concurrent audiovisual DMS task with equal proportions of auditory, visual, and audiovisual trials. Parallel to outcomes in human studies, accuracy was higher and response times were faster on audiovisual trials than either unisensory trial type. Unexpectedly, two subjects exhibited superior unimodal performance on auditory trials, a finding that contrasts with previous studies, but likely reflects their training history. Our results provide the first demonstration of a bimodal memory advantage in nonhuman primates, lending further validation to their use as a model for understanding audiovisual integration and memory processing in humans.

  5. Short-Term Power Plant GHG Emissions Forecasting Model

    International Nuclear Information System (INIS)

    Vidovic, D.

    2016-01-01

    In 2010, the share of greenhouse gas (GHG) emissions from power generation in the total emissions at the global level was about 25 percent. From January 1st, 2013 Croatian facilities have been involved in the European Union Emissions Trading System (EU ETS). The share of the ETS sector in total GHG emissions in Croatia in 2012 was about 30 percent, where power plants and heat generation facilities contributed to almost 50 percent. Since 2013 power plants are obliged to purchase all emission allowances. The paper describes the short-term climate forecasting model of greenhouse gas emissions from power plants while covering the daily load diagram of the system. Forecasting is done on an hourly domain typically for one day, it is possible and more days ahead. Forecasting GHG emissions in this way would enable power plant operators to purchase additional or sell surplus allowances on the market at the time. Example that describes the operation of the above mentioned forecasting model is given at the end of the paper.(author).

  6. Short-term energy outlook, quarterly projections, first quarter 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    The forecast period for this issue of the Outlook extends from the first quarter of 1998 through the fourth quarter of 1999. Values for the fourth quarter of 1997, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the first quarter 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are adjusted by EIA to reflect EIA assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 24 figs., 19 tabs.

  7. VAN method of short-term earthquake prediction shows promise

    Science.gov (United States)

    Uyeda, Seiya

    Although optimism prevailed in the 1970s, the present consensus on earthquake prediction appears to be quite pessimistic. However, short-term prediction based on geoelectric potential monitoring has stood the test of time in Greece for more than a decade [VarotsosandKulhanek, 1993] Lighthill, 1996]. The method used is called the VAN method.The geoelectric potential changes constantly due to causes such as magnetotelluric effects, lightning, rainfall, leakage from manmade sources, and electrochemical instabilities of electrodes. All of this noise must be eliminated before preseismic signals are identified, if they exist at all. The VAN group apparently accomplished this task for the first time. They installed multiple short (100-200m) dipoles with different lengths in both north-south and east-west directions and long (1-10 km) dipoles in appropriate orientations at their stations (one of their mega-stations, Ioannina, for example, now has 137 dipoles in operation) and found that practically all of the noise could be eliminated by applying a set of criteria to the data.

  8. Short-term uptake of heavy metals by periphyton algae

    Energy Technology Data Exchange (ETDEWEB)

    Vymazal, J.

    1984-12-31

    The utilization of periphyton for the removal of heavy metals from enriched small streams has been examined. By means of short-term batch laboratory experiments the courses of metal uptake have been studied. For uptake study naturally growing periphyton community and periphytic filamentous algae Cladophora glomerata and Oedogonium rivulare have been used. Uptakes of nine heavy metals (Pb, Cd, Cu, Co, Cr, Ni, Zn, Fe and Mn) have been determined during four hours exposure. In addition the influence of humic substances on heavy metals uptake has been determined. Uptake of all metals increased during four hours exposure but not in the same way. Some metals were removed continuously (Ni, Cr, Fe and Mn), other metals were removed more rapidly during the first hour or first two hours of exposure and then only slight removal continued (Cu, Pb, Cd, Co). Uptake of Zn was rather unambiguous. Results of these experiments suggest that the course of uptake for individual metals could be similar for most periphyton algae. It was established that humic substances significantly reduce heavy metals uptake. The highest decrease of uptake was observed in Cu, Cr, Co and Cd. The results of model experiments are being tested in a pilot scale with respect to the demands of engineering practice. (J.R.)

  9. Short term mutagenicity tests and their application to irradiated foods

    International Nuclear Information System (INIS)

    Phillips, B.J.; Elias, P.S.

    1980-01-01

    Although traditional long-term animal tests are likely to continue to be required, these are not only extremely costly but are coming more and more to be recognised as an imprecise and unsatisfactory method of testing the safety of irradiated foods for human consumption. It is therefore clearly advisable to include a selection of quicker and more direct testing methods in any toxicological assessment procedures. The International Project has therefore undertaken a study of the feasibility of using the newer systems for investigation of irradiated foodstuffs. Although some work in this field has already been carried out, some shortcomings in the published work can be identified which justify a more detailed and intensive research programme. As expected, little difficulty has been encountered in testing food by methods involving mammals, but considerable effort has been required to adapt in vitro systems. The use of enzymatic digestion in vitro to provide food samples for testing in mammalian cell cultures has never been attempted before and the procedures developed by the Project represent a positive contribution to methodology in this field. A series of foodstuffs is being tested by a wide spectrum of short-term tests and the first results are now being obtained. (orig./MG) [de

  10. Short-term generation scheduling model of Fujian hydro system

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jinwen [School of Hydropower and Information Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)], E-mail: dr.jinwen.wang@gmail.com

    2009-04-15

    The Fujian hydropower system (FHS) is one of the provincial hydropower systems with the most complicated hydraulic topology in China. This paper describes an optimization program that is required by Fujian Electric Power Company Ltd. (FEPCL) to aid the shift engineers in making decisions with the short-term hydropower scheduling such that the generation benefit can be maximal. The problem involves 27 reservoirs and is formulated as a nonlinear and discrete programming. It is a very challenging task to solve such a large-scale problem. In this paper, the Lagrangian multipliers are introduced to decompose the primal problem into a hydro subproblem and many individual plant-based subproblems, which are respectively solved by the improved simplex-like method (SLM) and the dynamic programming (DP). A numerical example is given and the derived solution is very close to the optimal one, with the distance in benefit less than 0.004%. All the data needed for the numerical example are presented in detail for further tests and studies from more experts and researchers.

  11. Short-term generation scheduling model of Fujian hydro system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jinwen [School of Hydropower and Information Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2009-04-15

    The Fujian hydropower system (FHS) is one of the provincial hydropower systems with the most complicated hydraulic topology in China. This paper describes an optimization program that is required by Fujian Electric Power Company Ltd. (FEPCL) to aid the shift engineers in making decisions with the short-term hydropower scheduling such that the generation benefit can be maximal. The problem involves 27 reservoirs and is formulated as a nonlinear and discrete programming. It is a very challenging task to solve such a large-scale problem. In this paper, the Lagrangian multipliers are introduced to decompose the primal problem into a hydro subproblem and many individual plant-based subproblems, which are respectively solved by the improved simplex-like method (SLM) and the dynamic programming (DP). A numerical example is given and the derived solution is very close to the optimal one, with the distance in benefit less than 0.004%. All the data needed for the numerical example are presented in detail for further tests and studies from more experts and researchers. (author)

  12. Visual short-term memory guides infants' visual attention.

    Science.gov (United States)

    Mitsven, Samantha G; Cantrell, Lisa M; Luck, Steven J; Oakes, Lisa M

    2018-08-01

    Adults' visual attention is guided by the contents of visual short-term memory (VSTM). Here we asked whether 10-month-old infants' (N = 41) visual attention is also guided by the information stored in VSTM. In two experiments, we modified the one-shot change detection task (Oakes, Baumgartner, Barrett, Messenger, & Luck, 2013) to create a simplified cued visual search task to ask how information stored in VSTM influences where infants look. A single sample item (e.g., a colored circle) was presented at fixation for 500 ms, followed by a brief (300 ms) retention interval and then a test array consisting of two items, one on each side of fixation. One item in the test array matched the sample stimulus and the other did not. Infants were more likely to look at the non-matching item than at the matching item, demonstrating that the information stored rapidly in VSTM guided subsequent looking behavior. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Dimension-based attention in visual short-term memory.

    Science.gov (United States)

    Pilling, Michael; Barrett, Doug J K

    2016-07-01

    We investigated how dimension-based attention influences visual short-term memory (VSTM). This was done through examining the effects of cueing a feature dimension in two perceptual comparison tasks (change detection and sameness detection). In both tasks, a memory array and a test array consisting of a number of colored shapes were presented successively, interleaved by a blank interstimulus interval (ISI). In Experiment 1 (change detection), the critical event was a feature change in one item across the memory and test arrays. In Experiment 2 (sameness detection), the critical event was the absence of a feature change in one item across the two arrays. Auditory cues indicated the feature dimension (color or shape) of the critical event with 80 % validity; the cues were presented either prior to the memory array, during the ISI, or simultaneously with the test array. In Experiment 1, the cue validity influenced sensitivity only when the cue was given at the earliest position; in Experiment 2, the cue validity influenced sensitivity at all three cue positions. We attributed the greater effectiveness of top-down guidance by cues in the sameness detection task to the more active nature of the comparison process required to detect sameness events (Hyun, Woodman, Vogel, Hollingworth, & Luck, Journal of Experimental Psychology: Human Perception and Performance, 35; 1140-1160, 2009).

  14. Short-term carcinogenesis evaluation of Casearia sylvestris

    Directory of Open Access Journals (Sweden)

    Cleide A.S. Tirloni

    Full Text Available Abstract Casearia sylvestris Sw., Salicaceae, is an important medicinal plant widely used in Brazil for the treatment of various cardiovascular disorders. This species was included as of interest by Brazilian Unified Health System. Although preclinical studies described cardiovascular protective effects and apparent absence of toxicity, no studies have evaluated its carcinogenic potential. In this study, we proposed a short-term carcinogenesis evaluation of C. sylvestris in Wistar rats, aiming to check the safety of this species to use it as proposed by Brazilian Unified Health System. C. sylvestris leaves were obtained and the crude extract was prepared by maceration from methanol/water. Wistar rats were orally treated for 12 weeks with 50, 250 or 500 mg kg−1 of crude extract or vehicle. Body weight, daily morbidity and mortality were monitored. Blood and bone marrow samples were collect for micronucleus test, comet assay and tumor markers evaluation. Vital organs were removed to macro and histopathological analyses. The crude extract did not induce mutagenic and genotoxic effects and no alterations were observed in important tumor markers. Finally, no detectable signs of injury through gross pathology or histopathological examinations were observed. Our results certify the absence of the crude extract toxicity, indicating its safety, even at prolonged exposure as proposed by Brazilian Unified Health System.

  15. Periodization of Carbohydrate Intake: Short-Term Effect on Performance

    Science.gov (United States)

    Marquet, Laurie-Anne; Hausswirth, Christophe; Molle, Odeline; Hawley, John A.; Burke, Louise M.; Tiollier, Eve; Brisswalter, Jeanick

    2016-01-01

    Background: “Sleep-low” consists of a sequential periodization of carbohydrate (CHO) availability—low glycogen recovery after “train high” glycogen-depleting interval training, followed by an overnight-fast and light intensity training (“train low”) the following day. This strategy leads to an upregulation of several exercise-responsive signaling proteins, but the chronic effect on performance has received less attention. We investigated the effects of short-term exposure to this strategy on endurance performance. Methods: Following training familiarization, 11 trained cyclists were divided into two groups for a one-week intervention—one group implemented three cycles of periodized CHO intake to achieve the sleep-low strategy over six training sessions (SL, CHO intake: 6 g·kg−1·day−1), whereas the control group consumed an even distribution of CHO over the day (CON). Tests were a 2 h submaximal ride and a 20 km time trial. Results: SL improved their performance (mean: +3.2%; p < 0.05) compared to CON. The improvement was associated with a change in pacing strategy with higher power output during the second part of the test. No change in substrate utilization was observed after the training period for either group. Conclusion: Implementing the “sleep-low” strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism. PMID:27897989

  16. Short-term efficacy of surgical treatment of secondary hyperparathyroidism.

    Science.gov (United States)

    Liang, Y; Sun, Y; Ren, L; Qi, X-W; Li, Y; Zhang, F

    2015-10-01

    We wished to explore short-term efficacy of surgical treatment of secondary hyperparathyroidism in patients with the end-stage renal disease. The treatment methods were subtotal or total parathyroidectomy, or total parathyroidectomy and autotransplantation. 63 patients with secondary hyperparathyroidism were randomly divided into three groups which were respectively treated with subtotal parathyroidectomy (SPTX group), total parathyroidectomy (TPTX group), or total parathyroidectomy and autotransplantation (TPTX+AT group). The surgical outcomes included operating time, transoperative bleeding volume, length of stay, and cost of hospitalization. In addition, complication (e.g., postoperative wound infection, hematoma, hypocalcemia in perioperative period) rates were compared among groups. Blood levels of calcium and parathyroid hormone were assessed before the surgery, and 1 day, 1 months, 3 months and 6 months after the surgery. The follow-up period comprised 6 months. Surgical outcomes were the lowest in SPTX group and the highest in in TPTX+AT group. There were no significant differences among groups in treatment efficacy. Complication rates were also comparable among the three groups. The occurrence of hypocalcemia was the lowest in SPTX group (p < 0.05 vs. other groups). However, postoperative relapse rate was the highest in this group (p < 0.05 vs. other groups). There were no correlations between the levels of blood calcium and PTH preoperatively and postoperatively. Appropriate surgical treatment is selected in accordance with the patient's condition and willingness, with the attention paid to the prevention of hypocalcemia.

  17. Circulating sclerostin is elevated in short-term and reduced in long-term SCI.

    Science.gov (United States)

    Battaglino, Ricardo A; Sudhakar, Supreetha; Lazzari, Antonio A; Garshick, Eric; Zafonte, Ross; Morse, Leslie R

    2012-09-01

    Spinal cord injury (SCI) causes profound bone loss due to muscle paralysis resulting in the inability to walk. Sclerostin, a Wnt signaling pathway antagonist produced by osteocytes, is a potent inhibitor of bone formation. Short-term studies in rodent models have demonstrated increased sclerostin in response to mechanical unloading that is reversed with reloading. Although sclerostin inhibition has been proposed as a potential therapy for bone loss, it is not known if sclerostin levels vary with duration of SCI in humans. We analyzed circulating sclerostin in 155 men with varying degrees of SCI who were 1 year or more post-injury. We report that sclerostin levels are greatest in subjects with short-term SCI (≤5 years post-injury) and decrease significantly over the first 5 years post-injury. There was no association between sclerostin and injury duration in subjects with long-term SCI (>5 years post-injury). In subjects with long-term SCI, sclerostin levels were positively associated with lower extremity bone density and bone mineral content. These data suggest that sclerostin levels are initially increased after SCI in response to mechanical unloading. This response is time-limited and as bone loss progresses, circulating sclerostin is lowest in subjects with severe osteoporosis. These findings support a dual role for sclerostin after SCI: a therapeutic target in acute SCI, and a biomarker of osteoporosis severity in chronic SCI. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Inhibition of connexin43 hemichannels impairs spatial short-term memory without affecting spatial working memory

    Directory of Open Access Journals (Sweden)

    Laura Walrave

    2016-12-01

    Full Text Available Astrocytes are active players in higher brain function as they can release gliotransmitters, which are essential for synaptic plasticity. Various mechanisms have been proposed for gliotransmission, including vesicular mechanisms as well as non-vesicular ones, for example by passive diffusion via connexin hemichannels (HCs. We here investigated whether interfering with connexin43 (Cx43 HCs influenced hippocampal spatial memory. We made use of the peptide Gap19 that blocks HCs but not gap junction channels and is specific for Cx43. To this end, we microinfused transactivator of transcription linked Gap19 (TAT-Gap19 into the brain ventricle of male NMRI mice and assessed spatial memory in a Y maze. We found that the in vivo blockade of Cx43 HCs did not affect the locomotor activity or spatial working memory in a spontaneous alternation Y maze task. Cx43 blockade did however significantly impair the spatial short-term memory in a delayed spontaneous alternation Y maze task. These results indicate that Cx43 HCs play a role in spatial short-term memory.

  19. Short-term visual deprivation does not enhance passive tactile spatial acuity.

    Directory of Open Access Journals (Sweden)

    Michael Wong

    Full Text Available An important unresolved question in sensory neuroscience is whether, and if so with what time course, tactile perception is enhanced by visual deprivation. In three experiments involving 158 normally sighted human participants, we assessed whether tactile spatial acuity improves with short-term visual deprivation over periods ranging from under 10 to over 110 minutes. We used an automated, precisely controlled two-interval forced-choice grating orientation task to assess each participant's ability to discern the orientation of square-wave gratings pressed against the stationary index finger pad of the dominant hand. A two-down one-up staircase (Experiment 1 or a Bayesian adaptive procedure (Experiments 2 and 3 was used to determine the groove width of the grating whose orientation each participant could reliably discriminate. The experiments consistently showed that tactile grating orientation discrimination does not improve with short-term visual deprivation. In fact, we found that tactile performance degraded slightly but significantly upon a brief period of visual deprivation (Experiment 1 and did not improve over periods of up to 110 minutes of deprivation (Experiments 2 and 3. The results additionally showed that grating orientation discrimination tends to improve upon repeated testing, and confirmed that women significantly outperform men on the grating orientation task. We conclude that, contrary to two recent reports but consistent with an earlier literature, passive tactile spatial acuity is not enhanced by short-term visual deprivation. Our findings have important theoretical and practical implications. On the theoretical side, the findings set limits on the time course over which neural mechanisms such as crossmodal plasticity may operate to drive sensory changes; on the practical side, the findings suggest that researchers who compare tactile acuity of blind and sighted participants should not blindfold the sighted participants.

  20. Intact Acquisition and Short-Term Retention of Non-Motor Procedural Learning in Parkinson's Disease.

    Directory of Open Access Journals (Sweden)

    Muriel T N Panouillères

    Full Text Available Procedural learning is a form of memory where people implicitly acquire a skill through repeated practice. People with Parkinson's disease (PD have been found to acquire motor adaptation, a form of motor procedural learning, similarly to healthy older adults but they have deficits in long-term retention. A similar pattern of normal learning on initial exposure with a deficit in retention seen on subsequent days has also been seen in mirror-reading, a form of non-motor procedural learning. It is a well-studied fact that disrupting sleep will impair the consolidation of procedural memories. Given the prevalence of sleep disturbances in PD, the lack of retention on following days seen in these studies could simply be a side effect of this well-known symptom of PD. Because of this, we wondered whether people with PD would present with deficits in the short-term retention of a non-motor procedural learning task, when the test of retention was done the same day as the initial exposure. The aim of the present study was then to investigate acquisition and retention in the immediate short term of cognitive procedural learning using the mirror-reading task in people with PD. This task involved two conditions: one where triads of mirror-inverted words were always new that allowed assessing the learning of mirror-reading skill and another one where some of the triads were presented repeatedly during the experiment that allowed assessing the word-specific learning. People with PD both ON and OFF their normal medication were compared to healthy older adults and young adults. Participants were re-tested 50 minutes break after initial exposure to probe for short-term retention. The results of this study show that all groups of participants acquired and retained the two skills (mirror-reading and word-specific similarly. These results suggest that neither healthy ageing nor the degeneration within the basal ganglia that occurs in PD does affect the mechanisms

  1. Nutritional status in short-term overtraining boxers

    Directory of Open Access Journals (Sweden)

    Alexandrova Albena

    2017-03-01

    Full Text Available The diet is essential to the recovery process in athletes, especially those undergoing intensive training. The continuous imbalance between loading and recovery leads to development of overtraining syndrome. The purpose of this study was to establish the changes in the nutritional status of short-term overtrained athletes. Twelve boxers from the team of National Spoils Academy Sofia, Bulgaria during their preparation for the National Championship 2016 were studied. The measurements were conducted three times.in the beginning of preparation (T1, 22 days later (2 and 10 days after (32 days after first measurement, in the beginning of the recovery period, one week prior the competition (T3.The measurements included basic anthropometric data, overtraining questionnaire RESTO-Sport and nutrition questionnaire, plasma concentration of testosterone and cortisol.On the data of dietary survey the percent proportion and the amount of daily consumed proteins, fats and carbohydrates were defined and the energy intake of the tested athletes was calculated. According to the RESTO-Sport a significant decrease in the ratio stress/recovery was observed in the period with the heaviest training load T2, and an increase was estimated in the pre­competition recovery period T3. It was found a typical for the overtraining syndrome decrease in the concentration of testosterone and the ratio of testosterone/cortisol in T3. In some respondents a reduction in carbohydrates and proteins intake was observed in T2 and especially in T3, which correlates with the hormonal changes. In this work the diet changes was discussed as a possible consequence and/or a cause of the overtraining syndrome.

  2. Nutritional status in short-term overtraining boxers

    Science.gov (United States)

    Alexandrova, Albena; Petrov, Lubomir; Zaekov, Nikolay; Bozhkov, Borislav; Zsheliaskova-Koynova, Zshivka

    2017-03-01

    The diet is essential to the recovery process in athletes, especially those undergoing intensive training. The continuous imbalance between loading and recovery leads to development of overtraining syndrome. The purpose of this study was to establish the changes in the nutritional status of short-term overtrained athletes. Twelve boxers from the team of National Spoils Academy Sofia, Bulgaria during their preparation for the National Championship 2016 were studied. The measurements were conducted three times.in the beginning of preparation (T1), 22 days later (2) and 10 days after (32 days after first measurement), in the beginning of the recovery period, one week prior the competition (T3).The measurements included basic anthropometric data, overtraining questionnaire RESTO-Sport and nutrition questionnaire, plasma concentration of testosterone and cortisol.On the data of dietary survey the percent proportion and the amount of daily consumed proteins, fats and carbohydrates were defined and the energy intake of the tested athletes was calculated. According to the RESTO-Sport a significant decrease in the ratio stress/recovery was observed in the period with the heaviest training load T2, and an increase was estimated in the pre­competition recovery period T3. It was found a typical for the overtraining syndrome decrease in the concentration of testosterone and the ratio of testosterone/cortisol in T3. In some respondents a reduction in carbohydrates and proteins intake was observed in T2 and especially in T3, which correlates with the hormonal changes. In this work the diet changes was discussed as a possible consequence and/or a cause of the overtraining syndrome.

  3. Short-term effect of antibiotics on human gut microbiota.

    Directory of Open Access Journals (Sweden)

    Suchita Panda

    Full Text Available From birth onwards, the human gut microbiota rapidly increases in diversity and reaches an adult-like stage at three years of age. After this age, the composition may fluctuate in response to external factors such as antibiotics. Previous studies have shown that resilience is not complete months after cessation of the antibiotic intake. However, little is known about the short-term effects of antibiotic intake on the gut microbial community. Here we examined the load and composition of the fecal microbiota immediately after treatment in 21 patients, who received broad-spectrum antibiotics such as fluoroquinolones and β-lactams. A fecal sample was collected from all participants before treatment and one week after for microbial load and community composition analyses by quantitative PCR and pyrosequencing of the 16S rRNA gene, respectively. Fluoroquinolones and β-lactams significantly decreased microbial diversity by 25% and reduced the core phylogenetic microbiota from 29 to 12 taxa. However, at the phylum level, these antibiotics increased the Bacteroidetes/Firmicutes ratio (p = 0.0007, FDR = 0.002. At the species level, our findings unexpectedly revealed that both antibiotic types increased the proportion of several unknown taxa belonging to the Bacteroides genus, a Gram-negative group of bacteria (p = 0.0003, FDR<0.016. Furthermore, the average microbial load was affected by the treatment. Indeed, the β-lactams increased it significantly by two-fold (p = 0.04. The maintenance of or possible increase detected in microbial load and the selection of Gram-negative over Gram-positive bacteria breaks the idea generally held about the effect of broad-spectrum antibiotics on gut microbiota.

  4. Remedial measures at the short-term regulated rivers

    International Nuclear Information System (INIS)

    Soimakallio, H.

    1995-01-01

    Building up and producing hydro power causes environmental effects, which are directed at the geomorfology, hydrology, water quality, organisms and landscape of the water system. To reduce and eliminate these various effects there are available an abundance of technical remedial measures, many of which contribute to several effects at the same time. In Finland a lot of remedial measures have been carried out at voluntary or obligatory bases. The information concerning remedial measures implemented in large build-up rivers were collected as a part of the study of the effects of the short-term regulation of hydro power plants. Material for the study was collected via literature, postal inquiry and terrain visits. Measures handled in the study were protection and reinforcement of shores, boating projects, submerged weirs, improvement of water turnover, fishery, clearing of peat rafts and stubs, landscaping, maintaining ice roads and shaping river banks. Nowadays planning and implementation of the remedial measures varies greatly depending on the nature and extent of the project. Large projects, which are more expensive, are naturally planned more carefully and comprehensively than simple routine measures. Also the quality of follow-up of the sites changes and the main portion of the information is received through terrain checks and direct feed-back from the users of the water system. In the future there is a need for model plans of the different routine measures. Also a systemic method to evaluate and compare different actions is needed to help decision making and to solve possible conflicts between different interests. Fishery, which is generally managed well, must in the future utilize better possibilities offered by other measures. According to the study there is no particular need to develop the follow-up systems. However, if the follow-up information is going to be used to develop the measures further, more systematic systems are needed for follow-up. (author)

  5. Familiarity speeds up visual short-term memory consolidation.

    Science.gov (United States)

    Xie, Weizhen; Zhang, Weiwei

    2017-06-01

    Existing long-term memory (LTM) can boost the number of retained representations over a short delay in visual short-term memory (VSTM). However, it is unclear whether and how prior LTM affects the initial process of transforming fragile sensory inputs into durable VSTM representations (i.e., VSTM consolidation). The consolidation speed hypothesis predicts faster consolidation for familiar relative to unfamiliar stimuli. Alternatively, the perceptual boost hypothesis predicts that the advantage in perceptual processing of familiar stimuli should add a constant boost for familiar stimuli during VSTM consolidation. To test these competing hypotheses, the present study examined how the large variance in participants' prior multimedia experience with Pokémon affected VSTM for Pokémon. In Experiment 1, the amount of time allowed for VSTM consolidation was manipulated by presenting consolidation masks at different intervals after the onset of to-be-remembered Pokémon characters. First-generation Pokémon characters that participants were more familiar with were consolidated faster into VSTM as compared with recent-generation Pokémon characters that participants were less familiar with. These effects were absent in participants who were unfamiliar with both generations of Pokémon. Although familiarity also increased the number of retained Pokémon characters when consolidation was uninterrupted but still incomplete due to insufficient encoding time in Experiment 1, this capacity effect was absent in Experiment 2 when consolidation was allowed to complete with sufficient encoding time. Together, these results support the consolidation speed hypothesis over the perceptual boost hypothesis and highlight the importance of assessing experimental effects on both processing and representation aspects of VSTM. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Short-term landfill methane emissions dependency on wind.

    Science.gov (United States)

    Delkash, Madjid; Zhou, Bowen; Han, Byunghyun; Chow, Fotini K; Rella, Chris W; Imhoff, Paul T

    2016-09-01

    Short-term (2-10h) variations of whole-landfill methane emissions have been observed in recent field studies using the tracer dilution method for emissions measurement. To investigate the cause of these variations, the tracer dilution method is applied using 1-min emissions measurements at Sandtown Landfill (Delaware, USA) for a 2-h measurement period. An atmospheric dispersion model is developed for this field test site, which is the first application of such modeling to evaluate atmospheric effects on gas plume transport from landfills. The model is used to examine three possible causes of observed temporal emissions variability: temporal variability of surface wind speed affecting whole landfill emissions, spatial variability of emissions due to local wind speed variations, and misaligned tracer gas release and methane emissions locations. At this site, atmospheric modeling indicates that variation in tracer dilution method emissions measurements may be caused by whole-landfill emissions variation with wind speed. Field data collected over the time period of the atmospheric model simulations corroborate this result: methane emissions are correlated with wind speed on the landfill surface with R(2)=0.51 for data 2.5m above ground, or R(2)=0.55 using data 85m above ground, with emissions increasing by up to a factor of 2 for an approximately 30% increase in wind speed. Although the atmospheric modeling and field test are conducted at a single landfill, the results suggest that wind-induced emissions may affect tracer dilution method emissions measurements at other landfills. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. A novel economy reflecting short-term load forecasting approach

    International Nuclear Information System (INIS)

    Lin, Cheng-Ting; Chou, Li-Der

    2013-01-01

    Highlights: ► We combine MA line of TAIEX and SVR to overcome the load demands over-prediction problems caused by the economic downturn. ► The Taiwan island-wide electricity power system was used as the case study. ► Short- to middle-term MA lines of TAIEX are found to be good economic input variables for load forecasting models. - Abstract: The global economic downturn in 2008 and 2009, which was spurred by the bankruptcy of Lehman Brothers, sharply reduced the demand for electricity load. Conventional load-forecasting approaches were unable to respond to sudden changes in the economy, because these approaches do not consider the effect of economic factors. Therefore, the over-prediction problem occurred. To overcome this problem, this paper proposes a novel, economy-reflecting, short-term load forecasting (STLF) approach based on theories of moving average (MA) line of stock index and machine learning. In this approach, the stock indices decision model is designed to reflect fluctuations in the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) series, which is selected as an optimal input variable in support vector regression load forecasting model at an appropriate timing. The Taiwan island-wide hourly electricity load demands from 2008 to 2010 are used as the case study for performance benchmarking. Results show that the proposed approach with a 60-day MA of the TAIEX as economic learning pattern achieves good forecasting performance. It outperforms the conventional approach by 29.16% on average during economic downturn-affected days. Overall, the proposed approach successfully overcomes the over-prediction problems caused by the economic downturn. To the best of our knowledge, this paper is the first attempt to apply MA line theory of stock index on STLF.

  8. Autoradiographic thyroid evaluation in short-term experimental diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Nascimento-Saba C.C.A.

    1998-01-01

    Full Text Available Previous studies have shown that in vitro thyroid peroxidase (TPO iodide oxidation activity is decreased and thyroid T4-5'-deiodinase activity is increased 15 days after induction of experimental diabetes mellitus (DM. In the present study we used thyroid histoautoradiography, an indirect assay of in vivo TPO activity, to determine the possible parallelism between the in vitro and in vivo changes induced by experimental DM. DM was induced in male Wistar rats (about 250 g body weight by a single ip streptozotocin injection (45 mg/kg, while control (C animals received a single injection of the vehicle. Seven and 30 days after diabetes induction, each diabetic and control animal was given ip a tracer dose of 125I (2 µCi, 2.5 h before thyroid excision. The glands were counted, weighed, fixed in Bouin's solution, embedded in paraffin and cut. The sections were stained with HE and exposed to NTB-2 emulsion (Kodak. The autohistograms were developed and the quantitative distribution of silver grains was evaluated with a computerized image analyzer system. Thyroid radioiodine uptake was significantly decreased only after 30 days of DM (C: 0.38 ± 0.05 vs DM: 0.20 ± 0.04%/mg thyroid, P<0.05 while in vivo TPO activity was significantly decreased 7 and 30 days after DM induction (C: 5.3 and 4.5 grains/100 µm2 vs DM: 2.9 and 1.6 grains/100 µm2, respectively, P<0.05 . These data suggest that insulin deficiency first reduces in vivo TPO activity during short-term experimental diabetes mellitus

  9. Short-term load forecasting of power system

    Science.gov (United States)

    Xu, Xiaobin

    2017-05-01

    In order to ensure the scientific nature of optimization about power system, it is necessary to improve the load forecasting accuracy. Power system load forecasting is based on accurate statistical data and survey data, starting from the history and current situation of electricity consumption, with a scientific method to predict the future development trend of power load and change the law of science. Short-term load forecasting is the basis of power system operation and analysis, which is of great significance to unit combination, economic dispatch and safety check. Therefore, the load forecasting of the power system is explained in detail in this paper. First, we use the data from 2012 to 2014 to establish the partial least squares model to regression analysis the relationship between daily maximum load, daily minimum load, daily average load and each meteorological factor, and select the highest peak by observing the regression coefficient histogram Day maximum temperature, daily minimum temperature and daily average temperature as the meteorological factors to improve the accuracy of load forecasting indicators. Secondly, in the case of uncertain climate impact, we use the time series model to predict the load data for 2015, respectively, the 2009-2014 load data were sorted out, through the previous six years of the data to forecast the data for this time in 2015. The criterion for the accuracy of the prediction is the average of the standard deviations for the prediction results and average load for the previous six years. Finally, considering the climate effect, we use the BP neural network model to predict the data in 2015, and optimize the forecast results on the basis of the time series model.

  10. Short-term clinical experience with hip resurfacing arthroplasty.

    Science.gov (United States)

    Cieliński, Łukasz; Kusz, Damian; Wojciechowski, Piotr; Dziuba, Anna

    2007-01-01

    This paper discusses the authors' experience with hip resurfacing arthroplasty. Although introduced many years ago, the method did not gain wide popularity because of poor long-term outcomes. At present, owing to the introduction of metal-on-metal bearings and hybrid fixation techniques, short- and mid-term results are very good and encourage wider use of this technique, especially in the younger and more active patients whose results with standard total hip replacements would be unsatisfactory. We performed 13 hip resurfacing arthroplasties at our institution between August 1, 2005, and May 1, 2006. Twelve patients reported for the scheduled follow-up and were included in the study. Treatment outcomes were assessed according to the Harris Hip Score. The short-term outcomes of hip resurfacing arthroplasties are encouraging. In the study group there were no intraoperative complications, infections, peripheral nerve palsy, hip dislocations or clinically overt vein thrombosis. All of the patients reported complete or major pain relief. Clinical assessment according to the Harris Hip Score revealed improvement from an average of 57.7 (20.1) points preoperatively to an average of 87.7 (12) points after the surgery. Crutches were used for a maximum of 6 weeks postoperatively. All of the patients are currently able to walk without crutches with full weight-bearing. 1) Hip resurfacing arthroplasty seems to be an advisable method of operative management of younger, active patients, in whom standard THR would be associated with a high risk of failure; it allows THR to be postponed and carried out as a revision surgery with the acetabular component already in place. 2) Despite the good short- and mid-term results, the utility of this method should be evaluated with caution due to the lack of adequate long-term follow-up data.

  11. Understanding Coral's Short-term Adaptive Ability to Changing Environment

    Science.gov (United States)

    Tisthammer, K.; Richmond, R. H.

    2016-02-01

    Corals in Maunalua Bay, Hawaii are under chronic pressures from sedimentation and terrestrial runoffs containing multiple pollutants as a result of large scale urbanization that has taken place in the last 100 years. However, some individual corals thrive despite the prolonged exposure to these environmental stressors, which suggests that these individuals may have adapted to withstand such stressors. A recent survey showed that the lobe coral Porites lobata from the `high-stress' nearshore site had an elevated level of stress ixnduced proteins, compared to those from the `low-stress,' less polluted offshore site. To understand the genetic basis for the observed differential stress responses between the nearshore and offshore P. lobata populations, an analysis of the lineage-scale population genetic structure, as well as a reciprocal transplant experiment were conducted. The result of the genetic analysis revealed a clear genetic differentiation between P. lobata from the nearshore site and the offshore site. Following the 30- day reciprocal transplant experiment, protein expression profiles and other stress-related physiological characteristics were compared between the two populations. The experimental results suggest that the nearshore genotype can cope better with sedimentation/pollutants than the offshore genotype. This indicates that the observed genetic differentiation is due to selection for tolerance to these environmental stressors. Understanding the little-known, linage-scale genetic variation in corals offers a critical insight into their short-term adaptive ability, which is indispensable for protecting corals from impending environmental and climate change. The results of this study also offer a valuable tool for resource managers to make effective decisions on coral reef conservation, such as designing marine protected areas that incorporate and maintain such genetic diversity, and establishing acceptable pollution run-off levels.

  12. The Cellular and Molecular Mechanisms of Immuno-suppression by Human Type 1 Regulatory T cells

    Directory of Open Access Journals (Sweden)

    Silvia eGregori

    2012-02-01

    Full Text Available The immuno-regulatory mechanisms of IL-10-producing type 1 regulatory T (Tr1 cells have been widely studied over the years. However, several recent discoveries have shed new light on the cellular and molecular mechanisms that human Tr1 cells use to control immune responses and induce tolerance. In this review we outline the well-known and newly discovered regulatory properties of human Tr1 cells and provide an in-depth comparison of the known suppressor mechanisms of Tr1 cells with FOXP3+ Treg. We also highlight the role that Tr1 cells play in promoting and maintaining tolerance in autoimmunity, allergy, and transplantation.

  13. Verbal short-term memory in Down's syndrome: an articulatory loop deficit?

    Science.gov (United States)

    Vicari, S; Marotta, L; Carlesimo, G A

    2004-02-01

    Verbal short-term memory, as measured by digit or word span, is generally impaired in individuals with Down's syndrome (DS) compared to mental age-matched controls. Moving from the working memory model, the present authors investigated the hypothesis that impairment in some of the articulatory loop sub-components is at the base of the deficient maintenance and recall of phonological representations in individuals with DS. Two experiments were carried out in a group of adolescents with DS and in typically developing children matched for mental age. In the first experiment, the authors explored the reliance of these subjects on the subvocal rehearsal mechanism during a word-span task and the effects produced by varying the frequency of occurrence of the words on the extension of the word span. In the second experiment, they investigated the functioning of the phonological store component of the articulatory loop in more detail. A reduced verbal span in DS was confirmed. Neither individuals with DS nor controls engaged in spontaneous subvocal rehearsal. Moreover, the data provide little support for defective functioning of the phonological store in DS. No evidence was found suggesting that a dysfunction of the articulatory loop and lexical-semantic competence significantly contributed to verbal span reduction in subjects with DS. Alternative explanations of defective verbal short-term memory in DS, such as a central executive system impairment, must be considered.

  14. Order recall in verbal short-term memory: The role of semantic networks.

    Science.gov (United States)

    Poirier, Marie; Saint-Aubin, Jean; Mair, Ali; Tehan, Gerry; Tolan, Anne

    2015-04-01

    In their recent article, Acheson, MacDonald, and Postle (Journal of Experimental Psychology: Learning, Memory, and Cognition 37:44-59, 2011) made an important but controversial suggestion: They hypothesized that (a) semantic information has an effect on order information in short-term memory (STM) and (b) order recall in STM is based on the level of activation of items within the relevant lexico-semantic long-term memory (LTM) network. However, verbal STM research has typically led to the conclusion that factors such as semantic category have a large effect on the number of correctly recalled items, but little or no impact on order recall (Poirier & Saint-Aubin, Quarterly Journal of Experimental Psychology 48A:384-404, 1995; Saint-Aubin, Ouellette, & Poirier, Psychonomic Bulletin & Review 12:171-177, 2005; Tse, Memory 17:874-891, 2009). Moreover, most formal models of short-term order memory currently suggest a separate mechanism for order coding-that is, one that is separate from item representation and not associated with LTM lexico-semantic networks. Both of the experiments reported here tested the predictions that we derived from Acheson et al. The findings show that, as predicted, manipulations aiming to affect the activation of item representations significantly impacted order memory.

  15. Short-Term Load Forecasting Model Based on Quantum Elman Neural Networks

    Directory of Open Access Journals (Sweden)

    Zhisheng Zhang

    2016-01-01

    Full Text Available Short-term load forecasting model based on quantum Elman neural networks was constructed in this paper. The quantum computation and Elman feedback mechanism were integrated into quantum Elman neural networks. Quantum computation can effectively improve the approximation capability and the information processing ability of the neural networks. Quantum Elman neural networks have not only the feedforward connection but also the feedback connection. The feedback connection between the hidden nodes and the context nodes belongs to the state feedback in the internal system, which has formed specific dynamic memory performance. Phase space reconstruction theory is the theoretical basis of constructing the forecasting model. The training samples are formed by means of K-nearest neighbor approach. Through the example simulation, the testing results show that the model based on quantum Elman neural networks is better than the model based on the quantum feedforward neural network, the model based on the conventional Elman neural network, and the model based on the conventional feedforward neural network. So the proposed model can effectively improve the prediction accuracy. The research in the paper makes a theoretical foundation for the practical engineering application of the short-term load forecasting model based on quantum Elman neural networks.

  16. A comparison of serial order short-term memory effects across verbal and musical domains.

    Science.gov (United States)

    Gorin, Simon; Mengal, Pierre; Majerus, Steve

    2018-04-01

    Recent studies suggest that the mechanisms involved in the short-term retention of serial order information may be shared across short-term memory (STM) domains such as verbal and visuospatial STM. Given the intrinsic sequential organization of musical material, the study of STM for musical information may be particularly informative about serial order retention processes and their domain-generality. The present experiment examined serial order STM for verbal and musical sequences in participants with no advanced musical expertise and experienced musicians. Serial order STM for verbal information was assessed via a serial order reconstruction task for digit sequences. In the musical domain, serial order STM was assessed using a novel melodic sequence reconstruction task maximizing the retention of tone order information. We observed that performance for the verbal and musical tasks was characterized by sequence length as well as primacy and recency effects. Serial order errors in both tasks were characterized by similar transposition gradients and ratios of fill-in:infill errors. These effects were observed for both participant groups, although the transposition gradients and ratios of fill-in:infill errors showed additional specificities for musician participants in the musical task. The data support domain-general serial order STM effects but also suggest the existence of additional domain-specific effects. Implications for models of serial order STM in verbal and musical domains are discussed.

  17. Methods for short-term control of Imperata grass in Peruvian Amazon

    Directory of Open Access Journals (Sweden)

    Zbynek Polesny

    2011-06-01

    Full Text Available The traditional control of Imperata brasiliensis grasslands used by farmers in the Peruvian Amazon is to burn the grass. The objective of this study was to compare different methods of short-term control. Biological, mechanical, chemical and traditional methods of control were compared. Herbicide spraying and manual weeding have shown to be very effective in reducing above- and below-ground biomass growth in the first 45 days after slashing the grass, with effects persisting in the longer term, but both are expensive methods. Shading seems to be less effective in the short-term, whereas it influences the Imperata growth in the longer term. After one year shading, glyphosate application and weeding significantly reduced aboveground biomass by 94, 67 and 53%; and belowground biomass by 76, 65 and 58%, respectively, compared to control. We also found a significant decrease of Imperata rhizomes in soil during time under shading. Burning has proved to have no significant effect on Imperata growth. The use of shade trees in a kind of agroforestry system could be a suitable method for small farmers to control Imperata grasslands.

  18. Short-term memory and electrical restitution in the canine transmural ventricle

    International Nuclear Information System (INIS)

    Zhang, Hong; Ueyama, Takeshi; Lin, Shien-Fong; Wang, Juan; Wu, Rui-Juan

    2011-01-01

    Cardiac short-term memory is an intrinsic property of paced myocardium that reflects the influence of pacing history. Using an optical mapping method to record membrane voltage and intracellular calcium (Ca 2+ i ), this study investigated the properties and mechanisms of short-term memory in isolated and perfused canine wedge preparations. In addition to the dynamic and S1S2 pacing protocols, a perturbed downsweep pacing protocol was used to get a complete overview of the restitution portrait. Abrupt changes in basic cycle length (BCL) were applied to investigate the accommodation process of action potential duration (APD). The results showed unobvious differences of memory among the epi-, mid- and endo-myocytes, implying an insignificant memory-induced transient heterogeneity in APD across the transmural canine hearts. With the decrease of pacing rate S1, memory gradually elevated and achieved a maximum around 400 ms, and then reduced as S1 decreased further, indicating a non-monotonic relationship between memory and the pacing rate. After suppressing the Ca 2+ i transient with ryanodine (3 µmol l −1 ), the accommodation process of APD to a new BCL significantly abbreviated (τ = 37.41 ± 4.42 stimuli before ryanodine, τ = 15.84 ± 4.74 stimuli after ryanodine, p < 0.01). Therefore, Ca 2+ i cycling was suggested to play an important role in memory during dynamic pacing

  19. Hippocampal Protein Kinase C Signaling Mediates the Short-Term Memory Impairment Induced by Delta9-Tetrahydrocannabinol.

    Science.gov (United States)

    Busquets-Garcia, Arnau; Gomis-González, Maria; Salgado-Mendialdúa, Victòria; Galera-López, Lorena; Puighermanal, Emma; Martín-García, Elena; Maldonado, Rafael; Ozaita, Andrés

    2018-04-01

    Cannabis affects cognitive performance through the activation of the endocannabinoid system, and the molecular mechanisms involved in this process are poorly understood. Using the novel object-recognition memory test in mice, we found that the main psychoactive component of cannabis, delta9-tetrahydrocannabinol (THC), alters short-term object-recognition memory specifically involving protein kinase C (PKC)-dependent signaling. Indeed, the systemic or intra-hippocampal pre-treatment with the PKC inhibitors prevented the short-term, but not the long-term, memory impairment induced by THC. In contrast, systemic pre-treatment with mammalian target of rapamycin complex 1 inhibitors, known to block the amnesic-like effects of THC on long-term memory, did not modify such a short-term cognitive deficit. Immunoblot analysis revealed a transient increase in PKC signaling activity in the hippocampus after THC treatment. Thus, THC administration induced the phosphorylation of a specific Ser residue in the hydrophobic-motif at the C-terminal tail of several PKC isoforms. This significant immunoreactive band that paralleled cognitive performance did not match in size with the major PKC isoforms expressed in the hippocampus except for PKCθ. Moreover, THC transiently enhanced the phosphorylation of the postsynaptic calmodulin-binding protein neurogranin in a PKC dependent manner. These data demonstrate that THC alters short-term object-recognition memory through hippocampal PKC/neurogranin signaling.

  20. Specific deficit of colour-colour short-term memory binding in sporadic and familial Alzheimer's disease.

    Science.gov (United States)

    Parra, Mario A; Sala, Sergio Della; Abrahams, Sharon; Logie, Robert H; Méndez, Luis Guillermo; Lopera, Francisco

    2011-06-01

    Short-term memory binding of visual features which are processed across different dimensions (shape-colour) is impaired in sporadic Alzheimer's disease, familial Alzheimer's disease, and in asymptomatic carriers of familial Alzheimer's disease. This study investigated whether Alzheimer's disease also impacts on within-dimension binding processes. The study specifically explored whether visual short-term memory binding of features of the same type (colour-colour) is sensitive to Alzheimer's disease. We used a neuropsychological battery and a short-term memory binding task to assess patients with sporadic Alzheimer's disease (Experiment 1), familial Alzheimer's disease (Experiment 2) due to the mutation E280A of the Presenilin-1 gene and asymptomatic carriers of the mutation. The binding task assessed change detection within arrays of unicoloured objects (Colour Only) or bicoloured objects the colours of which had to be remembered separately (Unbound Colours) or together (Bound Colours). Performance on the Bound Colours condition (1) explained the largest proportion of variance between patients (sporadic and familial Alzheimer's disease), (2) combined more sensitivity and specificity for the disease than other more traditional neuropsychological tasks, (3) identified asymptomatic carriers of the mutation even when traditional neuropsychological measures and other measures of short-term memory did not and, (4) contrary to shape-colour binding, correlated with measures of hippocampal functions. Colour-colour binding and shape-colour binding both appear to be sensitive to AD even though they seem to rely on different brain mechanisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. The uranium industry: long term planning for short term competition

    International Nuclear Information System (INIS)

    Vottero, X.

    2000-01-01

    Today, uranium producers face new challenges in terms of both production (new regulatory, environmental and social constraints) and market conditions (new sources of uranium supply, very low prices and tough competition). In such a context, long-term planning is not just a prerequisite to survive in the nuclear fuel cycle industry. In fact, it also contributes to sustaining nuclear electricity generation facing fierce competition from other energy sources in increasingly deregulated markets. (authors)

  2. Evaluation of Drinking Water Disinfectant Byproducts Compliance Data as an Indirect Measure for Short-Term Exposure in Humans.

    Science.gov (United States)

    Parvez, Shahid; Frost, Kali; Sundararajan, Madhura

    2017-05-20

    In the absence of shorter term disinfectant byproducts (DBPs) data on regulated Trihalomethanes (THMs) and Haloacetic acids (HAAs), epidemiologists and risk assessors have used long-term annual compliance (LRAA) or quarterly (QA) data to evaluate the association between DBP exposure and adverse birth outcomes, which resulted in inconclusive findings. Therefore, we evaluated the reliability of using long-term LRAA and QA data as an indirect measure for short-term exposure. Short-term residential tap water samples were collected in peak DBP months (May-August) in a community water system with five separate treatment stations and were sourced from surface or groundwater. Samples were analyzed for THMs and HAAs per the EPA (U.S. Environmental Protection Agency) standard methods (524.2 and 552.2). The measured levels of total THMs and HAAs were compared temporally and spatially with LRAA and QA data, which showed significant differences ( p water stations showed higher levels than LRAA or QA. Significant numbers of samples in surface water stations exceeded regulatory permissible limits: 27% had excessive THMs and 35% had excessive HAAs. Trichloromethane, trichloroacetic acid, and dichloroacetic acid were the major drivers of variability. This study suggests that LRAA and QA data are not good proxies of short-term exposure. Further investigation is needed to determine if other drinking water systems show consistent findings for improved regulation.

  3. Short-term change detection for UAV video

    Science.gov (United States)

    Saur, Günter; Krüger, Wolfgang

    2012-11-01

    In the last years, there has been an increased use of unmanned aerial vehicles (UAV) for video reconnaissance and surveillance. An important application in this context is change detection in UAV video data. Here we address short-term change detection, in which the time between observations ranges from several minutes to a few hours. We distinguish this task from video motion detection (shorter time scale) and from long-term change detection, based on time series of still images taken between several days, weeks, or even years. Examples for relevant changes we are looking for are recently parked or moved vehicles. As a pre-requisite, a precise image-to-image registration is needed. Images are selected on the basis of the geo-coordinates of the sensor's footprint and with respect to a certain minimal overlap. The automatic imagebased fine-registration adjusts the image pair to a common geometry by using a robust matching approach to handle outliers. The change detection algorithm has to distinguish between relevant and non-relevant changes. Examples for non-relevant changes are stereo disparity at 3D structures of the scene, changed length of shadows, and compression or transmission artifacts. To detect changes in image pairs we analyzed image differencing, local image correlation, and a transformation-based approach (multivariate alteration detection). As input we used color and gradient magnitude images. To cope with local misalignment of image structures we extended the approaches by a local neighborhood search. The algorithms are applied to several examples covering both urban and rural scenes. The local neighborhood search in combination with intensity and gradient magnitude differencing clearly improved the results. Extended image differencing performed better than both the correlation based approach and the multivariate alternation detection. The algorithms are adapted to be used in semi-automatic workflows for the ABUL video exploitation system of Fraunhofer

  4. Brivaracetam augments short-term depression and slows vesicle recycling.

    Science.gov (United States)

    Yang, Xiaofeng; Bognar, Joseph; He, Tianyu; Mohammed, Mouhari; Niespodziany, Isabelle; Wolff, Christian; Esguerra, Manuel; Rothman, Steven M; Dubinsky, Janet M

    2015-12-01

    Brivaracetam (BRV) decreases seizure activity in a number of epilepsy models and binds to the synaptic vesicle glycoprotein 2A (SV2A) with a higher affinity than the antiepileptic drug levetiracetam (LEV). Experiments were performed to determine if BRV acted similarly to LEV to induce or augment short-term depression (STD) under high-frequency neuronal stimulation and slow synaptic vesicle recycling. Electrophysiologic field excitatory postsynaptic potential (fEPSP) recordings were made from CA1 synapses in rat hippocampal slices loaded with BRV or LEV during intrinsic activity or with BRV actively loaded during hypertonic stimulation. STD was examined in response to 5 or 40 Hz stimulus trains. Presynaptic release of FM1-43 was visualized using two-photon microscopy to assess drug effects upon synaptic vesicle mobilization. When hippocampal slices were incubated in 0.1-30 μm BRV or 30 μm-1 mm LEV for 3 h, the relative CA1 field EPSPs decreased over the course of a high-frequency train of stimuli more than for control slices. This STD was frequency- and concentration-dependent, with BRV being 100-fold more potent than LEV. The extent of STD depended on the length of the incubation time for both drugs. Pretreatment with LEV occluded the effects of BRV. Repeated hypertonic sucrose treatments and train stimulation successfully unloaded BRV from recycling vesicles and reversed BRVs effects on STD, as previously reported for LEV. At their maximal concentrations, BRV slowed FM1-43 release to a greater extent than in slices loaded with LEV during prolonged stimulation. BRV, similar to LEV, entered into recycling synaptic vesicles and produced a frequency-dependent decrement of synaptic transmission at 100-fold lower concentrations than LEV. In addition, BRV slowed synaptic vesicle mobilization more effectively than LEV, suggesting that these drugs may modify multiple functions of the synaptic vesicle protein SV2A to curb synaptic transmission and limit epileptic activity

  5. Are there multiple visual short-term memory stores?

    Science.gov (United States)

    Sligte, Ilja G; Scholte, H Steven; Lamme, Victor A F

    2008-02-27

    Classic work on visual short-term memory (VSTM) suggests that people store a limited amount of items for subsequent report. However, when human observers are cued to shift attention to one item in VSTM during retention, it seems as if there is a much larger representation, which keeps additional items in a more fragile VSTM store. Thus far, it is not clear whether the capacity of this fragile VSTM store indeed exceeds the traditional capacity limits of VSTM. The current experiments address this issue and explore the capacity, stability, and duration of fragile VSTM representations. We presented cues in a change-detection task either just after off-set of the memory array (iconic-cue), 1,000 ms after off-set of the memory array (retro-cue) or after on-set of the probe array (post-cue). We observed three stages in visual information processing 1) iconic memory with unlimited capacity, 2) a four seconds lasting fragile VSTM store with a capacity that is at least a factor of two higher than 3) the robust and capacity-limited form of VSTM. Iconic memory seemed to depend on the strength of the positive after-image resulting from the memory display and was virtually absent under conditions of isoluminance or when intervening light masks were presented. This suggests that iconic memory is driven by prolonged retinal activation beyond stimulus duration. Fragile VSTM representations were not affected by light masks, but were completely overwritten by irrelevant pattern masks that spatially overlapped the memory array. We find that immediately after a stimulus has disappeared from view, subjects can still access information from iconic memory because they can see an after-image of the display. After that period, human observers can still access a substantial, but somewhat more limited amount of information from a high-capacity, but fragile VSTM that is overwritten when new items are presented to the eyes. What is left after that is the traditional VSTM store, with a limit of

  6. Are there multiple visual short-term memory stores?

    Directory of Open Access Journals (Sweden)

    Ilja G Sligte

    Full Text Available BACKGROUND: Classic work on visual short-term memory (VSTM suggests that people store a limited amount of items for subsequent report. However, when human observers are cued to shift attention to one item in VSTM during retention, it seems as if there is a much larger representation, which keeps additional items in a more fragile VSTM store. Thus far, it is not clear whether the capacity of this fragile VSTM store indeed exceeds the traditional capacity limits of VSTM. The current experiments address this issue and explore the capacity, stability, and duration of fragile VSTM representations. METHODOLOGY/PRINCIPAL FINDINGS: We presented cues in a change-detection task either just after off-set of the memory array (iconic-cue, 1,000 ms after off-set of the memory array (retro-cue or after on-set of the probe array (post-cue. We observed three stages in visual information processing 1 iconic memory with unlimited capacity, 2 a four seconds lasting fragile VSTM store with a capacity that is at least a factor of two higher than 3 the robust and capacity-limited form of VSTM. Iconic memory seemed to depend on the strength of the positive after-image resulting from the memory display and was virtually absent under conditions of isoluminance or when intervening light masks were presented. This suggests that iconic memory is driven by prolonged retinal activation beyond stimulus duration. Fragile VSTM representations were not affected by light masks, but were completely overwritten by irrelevant pattern masks that spatially overlapped the memory array. CONCLUSIONS/SIGNIFICANCE: We find that immediately after a stimulus has disappeared from view, subjects can still access information from iconic memory because they can see an after-image of the display. After that period, human observers can still access a substantial, but somewhat more limited amount of information from a high-capacity, but fragile VSTM that is overwritten when new items are presented

  7. DMPD: The interferon regulatory factor family in host defense: mechanism of action. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17502370 The interferon regulatory factor family in host defense: mechanism of acti....html) (.csml) Show The interferon regulatory factor family in host defense: mechanism of action. PubmedID 1...7502370 Title The interferon regulatory factor family in host defense: mechanism

  8. Regulatory Mechanisms Controlling Maturation of Serotonin Neuron Identity and Function.

    Science.gov (United States)

    Spencer, William C; Deneris, Evan S

    2017-01-01

    The brain serotonin (5-hydroxytryptamine; 5-HT) system has been extensively studied for its role in normal physiology and behavior, as well as, neuropsychiatric disorders. The broad influence of 5-HT on brain function, is in part due to the vast connectivity pattern of 5-HT-producing neurons throughout the CNS. 5-HT neurons are born and terminally specified midway through embryogenesis, then enter a protracted period of maturation, where they functionally integrate into CNS circuitry and then are maintained throughout life. The transcriptional regulatory networks controlling progenitor cell generation and terminal specification of 5-HT neurons are relatively well-understood, yet the factors controlling 5-HT neuron maturation are only recently coming to light. In this review, we first provide an update on the regulatory network controlling 5-HT neuron development, then delve deeper into the properties and regulatory strategies governing 5-HT neuron maturation. In particular, we discuss the role of the 5-HT neuron terminal selector transcription factor (TF) Pet-1 as a key regulator of 5-HT neuron maturation. Pet-1 was originally shown to positively regulate genes needed for 5-HT synthesis, reuptake and vesicular transport, hence 5-HT neuron-type transmitter identity. It has now been shown to regulate, both positively and negatively, many other categories of genes in 5-HT neurons including ion channels, GPCRs, transporters, neuropeptides, and other transcription factors. Its function as a terminal selector results in the maturation of 5-HT neuron excitability, firing characteristics, and synaptic modulation by several neurotransmitters. Furthermore, there is a temporal requirement for Pet-1 in the control of postmitotic gene expression trajectories thus indicating a direct role in 5-HT neuron maturation. Proper regulation of the maturation of cellular identity is critical for normal neuronal functioning and perturbations in the gene regulatory networks controlling

  9. Big Five Traits Related to Short-Term Mating: From Personality to Promiscuity across 46 Nations

    Directory of Open Access Journals (Sweden)

    David P. Schmitt

    2008-04-01

    Full Text Available As part of the International Sexuality Description Project, 13,243 participants from 46 nations responded to self-report measures of personality and mating behavior. Several traits showed consistent links with short-term mating. Extraversion positively correlated with interest in short-term mating, unrestricted sociosexuality, having engaged in short-term mate poaching attempts, having succumbed to short-term poaching attempts of others, and lacking relationship exclusivity. Low levels of agreeableness and conscientiousness also related to short-term mating, especially with extra-pair mating. Neuroticism and openness were associated with short-term mating as well, but these links were less consistent across sex and nation. Nation-level links between personality and sexuality replicated within-region findings, such as the strong association between national extraversion and national sociosexuality. Discussion focuses on the origins of personality-sexuality links and their implications across nations.

  10. Short-Term Depression, Temporal Summation, and Onset Inhibition Shape Interval Tuning in Midbrain Neurons

    Science.gov (United States)

    Baker, Christa A.

    2014-01-01

    A variety of synaptic mechanisms can contribute to single-neuron selectivity for temporal intervals in sensory stimuli. However, it remains unknown how these mechanisms interact to establish single-neuron sensitivity to temporal patterns of sensory stimulation in vivo. Here we address this question in a circuit that allows us to control the precise temporal patterns of synaptic input to interval-tuned neurons in behaviorally relevant ways. We obtained in vivo intracellular recordings under multiple levels of current clamp from midbrain neurons in the mormyrid weakly electric fish Brienomyrus brachyistius during stimulation with electrosensory pulse trains. To reveal the excitatory and inhibitory inputs onto interval-tuned neurons, we then estimated the synaptic conductances underlying responses. We found short-term depression in excitatory and inhibitory pathways onto all interval-tuned neurons. Short-interval selectivity was associated with excitation that depressed less than inhibition at short intervals, as well as temporally summating excitation. Long-interval selectivity was associated with long-lasting onset inhibition. We investigated tuning after separately nullifying the contributions of temporal summation and depression, and found the greatest diversity of interval selectivity among neurons when both mechanisms were at play. Furthermore, eliminating the effects of depression decreased sensitivity to directional changes in interval. These findings demonstrate that variation in depression and summation of excitation and inhibition helps to establish tuning to behaviorally relevant intervals in communication signals, and that depression contributes to neural coding of interval sequences. This work reveals for the first time how the interplay between short-term plasticity and temporal summation mediates the decoding of temporal sequences in awake, behaving animals. PMID:25339741

  11. Qualitative similarities in the visual short-term memory of pigeons and people

    OpenAIRE

    Gibson, Brett; Wasserman, Edward; Luck, Steven J.

    2011-01-01

    Visual short-term memory plays a key role in guiding behavior, and individual differences in visual short-term memory capacity are strongly predictive of higher cognitive abilities. To provide a broader evolutionary context for understanding this memory system, we directly compared the behavior of pigeons and humans on a change detection task. Although pigeons had a lower storage capacity and a higher lapse rate than humans, both species stored multiple items in short-term memory and conforme...

  12. Maternal separation modulates short-term behavioral and physiological indices of the stress response.

    Science.gov (United States)

    Litvin, Yoav; Tovote, Philip; Pentkowski, Nathan S; Zeyda, Thomas; King, Lanikea B; Vasconcellos, Amy J; Dunlap, Christopher; Spiess, Joachim; Blanchard, D Caroline; Blanchard, Robert J

    2010-07-01

    olfactory-mediated freezing, not in mechanisms of learning and memory per se. These findings may have direct relevance for understanding the mechanisms by which early-life adverse experiences produce short-term and lasting psychopathologies. Copyright 2010 Elsevier Inc. All rights reserved.

  13. What are the differences between long-term, short-term, and working memory?

    OpenAIRE

    Cowan, Nelson

    2008-01-01

    In the recent literature there has been considerable confusion about the three types of memory: long-term, short-term, and working memory. This chapter strives to reduce that confusion and makes up-to-date assessments of these types of memory. Long- and short-term memory could differ in two fundamental ways, with only short-term memory demonstrating (1) temporal decay and (2) chunk capacity limits. Both properties of short-term memory are still controversial but the current literature is rath...

  14. An Artificial Neural Network Based Short-term Dynamic Prediction of Algae Bloom

    Directory of Open Access Journals (Sweden)

    Yao Junyang

    2014-06-01

    Full Text Available This paper proposes a method of short-term prediction of algae bloom based on artificial neural network. Firstly, principal component analysis is applied to water environmental factors in algae bloom raceway ponds to get main factors that influence the formation of algae blooms. Then, a model of short-term dynamic prediction based on neural network is built with the current chlorophyll_a values as input and the chlorophyll_a values in the next moment as output to realize short-term dynamic prediction of algae bloom. Simulation results show that the model can realize short-term prediction of algae bloom effectively.

  15. DYNAMICS OF THE ANXIETY DISORDERS IN THE COURSE OF SHORT-TERM PSYCHOTHERAPY

    Directory of Open Access Journals (Sweden)

    T.N. Hmylova

    2008-06-01

    Full Text Available The tendency of psychotherapy modern concepts referring to the short-term forms having been taken into account, we carried out the research aimed at the study of short-term form personality-oriented psychotherapy effect on the anxiety disorder dynamics. 103 patients with neurotic disorders were examined in the neurosis and psychotherapy department of the Bekhterev Psychoneurological Research Institute. The findings revealed the situational and personal anxiety level to be objectively decreased in the short-term group psychotherapy course. The short-term group psychotherapy was proved to bean effective method in anxiety disorders treatment considering indications and limitations.

  16. Glucose- and nitrogen sensing and regulatory mechanisms in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Rødkaer, Steven V; Færgeman, Nils J.

    2014-01-01

    Pro- and eukaryotic cells are constantly challenged by varying concentrations of nutrients in their environment. Perceiving and adapting to such changes are therefore crucial for cellular viability. Thus, numerous specialized cellular receptors continuously sense and react to the availability...... of nutrients such as glucose and nitrogen. When stimulated, these receptors initiate various cellular signaling pathways, which in concert constitute a complex regulatory network. To ensure a highly specific response, these pathways and networks cross-communicate with each other and are regulated at several...

  17. Plant Perception and Short-Term Responses to Phytophagous Insects and Mites

    Directory of Open Access Journals (Sweden)

    M. Estrella Santamaria

    2018-05-01

    Full Text Available Plant–pest relationships involve complex processes encompassing a network of molecules, signals, and regulators for overcoming defenses they develop against each other. Phytophagous arthropods identify plants mainly as a source of food. In turn, plants develop a variety of strategies to avoid damage and survive. The success of plant defenses depends on rapid and specific recognition of the phytophagous threat. Subsequently, plants trigger a cascade of short-term responses that eventually result in the production of a wide range of compounds with defense properties. This review deals with the main features involved in the interaction between plants and phytophagous insects and acari, focusing on early responses from the plant side. A general landscape of the diverse strategies employed by plants within the first hours after pest perception to block the capability of phytophagous insects to develop mechanisms of resistance is presented, with the potential of providing alternatives for pest control.

  18. Motor Habits in Visuo-manual Tracking: Manifestation of an Unconscious Short-Term Motor Memory?

    Directory of Open Access Journals (Sweden)

    Andreas Hufschmidt

    1990-01-01

    Full Text Available Normal subjects were tested in short, repetitive trials of a tracking task, with an identical shape of target movement being used throughout one session. Analysis of the net error curves (pursuit minus target movement revealed that subjects regularly exhibit a remoteness effect: neighbouring trials were more similar than distant ones. The effect is demonstrated to be stronger in the absence of visual cues, and was found to be absent in a patient with complete loss of proprioception when he was performing without visual feedback as well. The results are discussed in terms of a short term memory store contributing to unconscious movement habits in tracking. This may represent part of the motor learning process working together with conscious visuo-motor control mechanisms. Its function is probably related to the acquisition of automatic movements.

  19. Neural correlates of auditory short-term memory in rostral superior temporal cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer; Yin, Pingbo

    2014-12-01

    Auditory short-term memory (STM) in the monkey is less robust than visual STM and may depend on a retained sensory trace, which is likely to reside in the higher-order cortical areas of the auditory ventral stream. We recorded from the rostral superior temporal cortex as monkeys performed serial auditory delayed match-to-sample (DMS). A subset of neurons exhibited modulations of their firing rate during the delay between sounds, during the sensory response, or during both. This distributed subpopulation carried a predominantly sensory signal modulated by the mnemonic context of the stimulus. Excitatory and suppressive effects on match responses were dissociable in their timing and in their resistance to sounds intervening between the sample and match. Like the monkeys' behavioral performance, these neuronal effects differ from those reported in the same species during visual DMS, suggesting different neural mechanisms for retaining dynamic sounds and static images in STM. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. A transcriptome resource for Antarctic krill (Euphausia superba Dana) exposed to short-term stress

    KAUST Repository

    Martins, Maria João F

    2015-10-01

    Euphausia superba is a keystone species in Antarctic food webs. However, the continued decrease in stock density raises concerns over the resilience and adaptive potential of krill to withstand the current rate of environmental change. We undertook a transcriptome-scale approach (454 pyrosequencing) as a baseline for future studies addressing the physiological response of krill to short-term food shortage and natural UV-B stress. The final assembly resulted in a total of 26,415 contigs, 39.8% of which were putatively annotated. Exploratory analyses indicate an overall reduction in protein synthesis under food shortage while UV stress resulted in the activation of photo-protective mechanisms. © 2015.

  1. A transcriptome resource for Antarctic krill (Euphausia superba Dana) exposed to short-term stress

    KAUST Repository

    Martins, Maria Joã o F; Lago-Leston, Asuncion; Anjos, Antonio; Duarte, Carlos M.; Agusti, Susana; Serrã o, Ester A.; Pearson, Gareth A.

    2015-01-01

    Euphausia superba is a keystone species in Antarctic food webs. However, the continued decrease in stock density raises concerns over the resilience and adaptive potential of krill to withstand the current rate of environmental change. We undertook a transcriptome-scale approach (454 pyrosequencing) as a baseline for future studies addressing the physiological response of krill to short-term food shortage and natural UV-B stress. The final assembly resulted in a total of 26,415 contigs, 39.8% of which were putatively annotated. Exploratory analyses indicate an overall reduction in protein synthesis under food shortage while UV stress resulted in the activation of photo-protective mechanisms. © 2015.

  2. Feature-based and object-based attention orientation during short-term memory maintenance.

    Science.gov (United States)

    Ku, Yixuan

    2015-12-01

    Top-down attention biases the short-term memory (STM) processing at multiple stages. Orienting attention during the maintenance period of STM by a retrospective cue (retro-cue) strengthens the representation of the cued item and improves the subsequent STM performance. In a recent article, Backer et al. (Backer KC, Binns MA, Alain C. J Neurosci 35: 1307-1318, 2015) extended these findings from the visual to the auditory domain and combined electroencephalography to dissociate neural mechanisms underlying feature-based and object-based attention orientation. Both event-related potentials and neural oscillations explained the behavioral benefits of retro-cues and favored the theory that feature-based and object-based attention orientation were independent. Copyright © 2015 the American Physiological Society.

  3. Short-term changes in respiratory biomarkers after swimming in a chlorinated pool.

    Science.gov (United States)

    Font-Ribera, Laia; Kogevinas, Manolis; Zock, Jan-Paul; Gómez, Federico P; Barreiro, Esther; Nieuwenhuijsen, Mark J; Fernandez, Pilar; Lourencetti, Carolina; Pérez-Olabarría, Maitane; Bustamante, Mariona; Marcos, Ricard; Grimalt, Joan O; Villanueva, Cristina M

    2010-11-01

    Swimming in chlorinated pools involves exposure to disinfection by-products (DBPs) and has been associated with impaired respiratory health. We evaluated short-term changes in several respiratory biomarkers to explore mechanisms of potential lung damage related to swimming pool exposure. We measured lung function and biomarkers of airway inflammation [fractional exhaled nitric oxide (FeNO), eight cytokines, and vascular endothelial growth factor (VEGF) in exhaled breath condensate], oxidative stress (8-isoprostane in exhaled breath condensate), and lung permeability [surfactant protein D (SP-D) and the Clara cell secretory protein (CC16) in serum] in 48 healthy nonsmoking adults before and after they swam for 40 min in a chlorinated indoor swimming pool. We measured trihalomethanes in exhaled breath as a marker of individual exposure to DBPs. Energy expenditure during swimming, atopy, and CC16 genotype (rs3741240) were also determined. Median serum CC16 levels increased from 6.01 to 6.21 microg/L (average increase, 3.3%; paired Wilcoxon test p = 0.03), regardless of atopic status and CC16 genotype. This increase was explained both by energy expenditure and different markers of DBP exposure in multivariate models. FeNO was unchanged overall but tended to decrease among atopics. We found no significant changes in lung function, SP-D, 8-isoprostane, eight cytokines, or VEGF. We detected a slight increase in serum CC16, a marker of lung epithelium permeability, in healthy adults after they swam in an indoor chlorinated pool. Exercise and DBP exposure explained this association, without involving inflammatory mechanisms. Further research is needed to confirm the results, establish the clinical relevance of short-term serum CC16 changes, and evaluate the long-term health impacts.

  4. Simulating the Effects of Short-Term Synaptic Plasticity on Postsynaptic Dynamics in the Globus Pallidus

    Directory of Open Access Journals (Sweden)

    Moran eBrody

    2013-08-01

    Full Text Available The rat globus pallidus (GP is one of the nuclei of the basal ganglia and plays an important role in a variety of motor and cognitive processes. In vivo studies have shown that repetitive stimulation evokes complex modulations of GP activity. In vitro and computational studies have suggested that short-term synaptic plasticity (STP could be one of the underlying mechanisms. The current study used simplified single compartment modeling to explore the possible effect of STP on the activity of GP neurons during low and high frequency stimulation. To do this we constructed a model of a GP neuron connected to a small network of neurons from the three major input sources to GP neurons: striatum (Str, subthalamic nucleus (STN and GP collaterals. All synapses were implemented with a kinetic model of STP. The in vitro recordings of responses to low frequency repetitive stimulation were highly reconstructed, including rate changes and locking to the stimulus. Mainly involved were fast forms of plasticity which have been found at these synapses. . The simulations were qualitatively compared to a data set previously recorded in vitro in our lab. Reconstructions of experimental responses to high frequency stimulation required adding slower forms of plasticity to the STN and GP collateral synapses, as well as adding metabotropic receptors to the STN-GP synapses. These finding suggest the existence of as yet unreported slower short-term dynamics in the GP. The computational model made additional predictions about GP activity during low and high frequency stimulation that may further our understanding of the mechanisms underlying repetative stimulation of the GP.

  5. Distribution of Short-Term and Lifetime Predicted Risks of Cardiovascular Diseases in Peruvian Adults.

    Science.gov (United States)

    Quispe, Renato; Bazo-Alvarez, Juan Carlos; Burroughs Peña, Melissa S; Poterico, Julio A; Gilman, Robert H; Checkley, William; Bernabé-Ortiz, Antonio; Huffman, Mark D; Miranda, J Jaime

    2015-08-07

    Short-term risk assessment tools for prediction of cardiovascular disease events are widely recommended in clinical practice and are used largely for single time-point estimations; however, persons with low predicted short-term risk may have higher risks across longer time horizons. We estimated short-term and lifetime cardiovascular disease risk in a pooled population from 2 studies of Peruvian populations. Short-term risk was estimated using the atherosclerotic cardiovascular disease Pooled Cohort Risk Equations. Lifetime risk was evaluated using the algorithm derived from the Framingham Heart Study cohort. Using previously published thresholds, participants were classified into 3 categories: low short-term and low lifetime risk, low short-term and high lifetime risk, and high short-term predicted risk. We also compared the distribution of these risk profiles across educational level, wealth index, and place of residence. We included 2844 participants (50% men, mean age 55.9 years [SD 10.2 years]) in the analysis. Approximately 1 of every 3 participants (34% [95% CI 33 to 36]) had a high short-term estimated cardiovascular disease risk. Among those with a low short-term predicted risk, more than half (54% [95% CI 52 to 56]) had a high lifetime predicted risk. Short-term and lifetime predicted risks were higher for participants with lower versus higher wealth indexes and educational levels and for those living in urban versus rural areas (PPeruvian adults were classified as low short-term risk but high lifetime risk. Vulnerable adults, such as those from low socioeconomic status and those living in urban areas, may need greater attention regarding cardiovascular preventive strategies. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  6. Distribution of Short-Term and Lifetime Predicted Risks of Cardiovascular Diseases in Peruvian Adults

    Science.gov (United States)

    Quispe, Renato; Bazo-Alvarez, Juan Carlos; Burroughs Peña, Melissa S; Poterico, Julio A; Gilman, Robert H; Checkley, William; Bernabé-Ortiz, Antonio; Huffman, Mark D; Miranda, J Jaime

    2015-01-01

    Background Short-term risk assessment tools for prediction of cardiovascular disease events are widely recommended in clinical practice and are used largely for single time-point estimations; however, persons with low predicted short-term risk may have higher risks across longer time horizons. Methods and Results We estimated short-term and lifetime cardiovascular disease risk in a pooled population from 2 studies of Peruvian populations. Short-term risk was estimated using the atherosclerotic cardiovascular disease Pooled Cohort Risk Equations. Lifetime risk was evaluated using the algorithm derived from the Framingham Heart Study cohort. Using previously published thresholds, participants were classified into 3 categories: low short-term and low lifetime risk, low short-term and high lifetime risk, and high short-term predicted risk. We also compared the distribution of these risk profiles across educational level, wealth index, and place of residence. We included 2844 participants (50% men, mean age 55.9 years [SD 10.2 years]) in the analysis. Approximately 1 of every 3 participants (34% [95% CI 33 to 36]) had a high short-term estimated cardiovascular disease risk. Among those with a low short-term predicted risk, more than half (54% [95% CI 52 to 56]) had a high lifetime predicted risk. Short-term and lifetime predicted risks were higher for participants with lower versus higher wealth indexes and educational levels and for those living in urban versus rural areas (PPeruvian adults were classified as low short-term risk but high lifetime risk. Vulnerable adults, such as those from low socioeconomic status and those living in urban areas, may need greater attention regarding cardiovascular preventive strategies. PMID:26254303

  7. The effect of visual arrangement on visuospatial short-term memory: Insights from children with 22q11.2 deletion syndrome.

    Science.gov (United States)

    Attout, Lucie; Noël, Marie-Pascale; Rousselle, Laurence

    2018-04-11

    Recent models of visuospatial (VSSP) short-term memory postulate the existence of two dissociable mechanisms depending on whether VSSP information is presented simultaneously or sequentially. However, they do not specify to what extent VSSP short-term memory is under the influence of general VSSP processing. This issue was examined in people with 22q11.2 deletion syndrome, a genetic condition involving a VSSP deficit. The configuration of VSSP information was manipulated (structured vs. unstructured) to explore the impact of arrangement on VSSP short-term memory. Two presentation modes were used to see whether the VSSP arrangement has the same impact on simultaneous and sequential short-term memory. Compared to children matched on chronological age, children with 22q11.2 deletion syndrome showed impaired performance only for structured arrangement, regardless of the presentation mode, suggesting an influence of VSSP processing on VSSP short-term memory abilities. A revised cognitive architecture for a model of VSSP short-term memory is proposed.

  8. Regulatory Coherence and Standardization Mechanisms in the Trans-Pacific Partnership

    Directory of Open Access Journals (Sweden)

    Cai Phoenix X. F.

    2016-12-01

    Full Text Available This article posits a new taxonomy and framework for assessing regulatory coherence in the new generation of mega-regional, cross-cutting free trade agreements. Using the Trans-Pacific Partnership as the primary example, this article situates the rise of regulatory coherence within the current trade landscape, provides clear definitions of regulatory coherence, and argues that the real engine of regulatory coherence lies in the work of international standard setting organizations. This work has been little examined in the current literature. The article provides a detailed examination of the mechanics by which the Trans-Pacific Partnership promotes regulatory standardization and concludes with some normative implications and calls for future research.

  9. A simulation approach for analysis of short-term security of natural gas supply in Colombia

    International Nuclear Information System (INIS)

    Villada, Juan; Olaya, Yris

    2013-01-01

    Achieving security of gas supply implies diversifying gas sources, while having enough supply, transportation, and storage capacity to meet demand peaks and supply interruptions. Devising a strategy for securing gas supply is not straightforward because gas supply depends on complex interactions of production, demand and infrastructure, and it is exposed to economic, regulatory, political, environmental and technical risks. To address this complexity, we propose a simulation approach that replicates the structure of the gas supply chain, including transportation constraints and demand fluctuations. We build and calibrate a computer model for the Colombian gas sector, and run the model to assess the impact of expanding transportation capacity and increasing market flexibility on the security of supply. Our analysis focuses on the operation and planned and proposed expansions of the transportation infrastructure because adequate regulation and development of this infrastructure can contribute to increase the security of supply in the gas sector. We find that proposed import facilities, specifically LNG import terminals at Buenaventura, increase system's security under the current market structure. - Highlights: ► We build a simulation model for analyzing natural gas trade in Colombia. ► The model captures the structure of the gas network and on market rules. ► We simulate investment decisions to increase short-term security of supply. ► Securing supply would need LNG imports and expansion of pipeline capacity.

  10. Short-term variability of 10 trans-Neptunian objects

    Czech Academy of Sciences Publication Activity Database

    Thirouin, A.; Ortiz, J.L.; Campo Bagatin, A.; Pravec, Petr; Morales, N.; Hainaut, O.; Duffard, R.

    2012-01-01

    Roč. 424, č. 4 (2012), s. 3156-3177 ISSN 0035-8711 Institutional support: RVO:67985815 Keywords : photometric techniques * kuiper belt general Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.521, year: 2012

  11. Intact organism, short-term studies using 11C

    International Nuclear Information System (INIS)

    Spence, R.D.; Sharpe, P.J.H.

    1991-01-01

    Experimental investigation of biochemical pathways and biophysical mechanisms is difficult because in many cases more than one pathway or mechanism is involved. Ideally, a physiological tracer should be used to follow the uptake, transport, and assimilation of materials such as carbon and nitrogen to characterize the movements and mechanisms of physiological processes. Real-time measurements of net photosynthesis and dark respiration of plants have been possible since the development of the infrared gas analyzer (IRGA), allowing the intensive investigation of mechanisms and dynamics of CO 2 assimilation in green plants. Comparable research on the movement of carbon within the plant, however, requires another technique that allows real-time observations of carbon transport. This chapter describes how the short-lived radioisotope 11 C can be used to conduct plant physiological studies that are difficult or impossible to make using other isotopes such as 14 C

  12. Short-term hypoxia/reoxygenation activates the angiogenic pathway ...

    Indian Academy of Sciences (India)

    2013-04-20

    Apr 20, 2013 ... angiogenic pathway in the rat caudate putamen as a neuroprotective mechanism to hypoxia .... (1:3 w/v) with a homogenator (Pellet Pestle Motor Cordless, ..... showing that the capillary density in the rat cerebral cortex was.

  13. Community in a Hurry: Social Contracts and Social Covenants in Short-Term ESL Courses

    Science.gov (United States)

    Martinsen, Rob A.

    2009-01-01

    Like many adult ESL instructors, the author has felt firsthand the challenges of creating community in short-term courses. Through his experience, he has noticed that in order to successfully build community in short-term ESL courses, teachers need to lay a foundation for social contracts and social covenants from the first day of the course and…

  14. Short-Term Contract Work in Adult Education (I) and (II).

    Science.gov (United States)

    Hall, Dorothea; McMath, Patricia

    1986-01-01

    This two-part article discusses short-term project contracts for adult education staff. Part one covers implications of this trend for the service and for the staff involved. Part two looks at short-term contracts from the management viewpoint. (CH)

  15. Poor Phonemic Discrimination Does Not Underlie Poor Verbal Short-Term Memory in Down Syndrome

    Science.gov (United States)

    Purser, Harry R. M.; Jarrold, Christopher

    2013-01-01

    Individuals with Down syndrome tend to have a marked impairment of verbal short-term memory. The chief aim of this study was to investigate whether phonemic discrimination contributes to this deficit. The secondary aim was to investigate whether phonological representations are degraded in verbal short-term memory in people with Down syndrome…

  16. How Emotional Pictures Influence Visuospatial Binding in Short-Term Memory in Ageing and Alzheimer's Disease?

    Science.gov (United States)

    Borg, Celine; Leroy, Nicolas; Favre, Emilie; Laurent, Bernard; Thomas-Anterion, Catherine

    2011-01-01

    The present study examines the prediction that emotion can facilitate short-term memory. Nevertheless, emotion also recruits attention to process information, thereby disrupting short-term memory when tasks involve high attentional resources. In this way, we aimed to determine whether there is a differential influence of emotional information on…

  17. 34 CFR 664.11 - What is a short-term seminar project?

    Science.gov (United States)

    2010-07-01

    ... short-term seminar project is— (a) Designed to help integrate international studies into an institution... 34 Education 3 2010-07-01 2010-07-01 false What is a short-term seminar project? 664.11 Section 664.11 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF...

  18. Short-term adaptations as a response to travel time: results of a stated adaptation experimentincreases

    NARCIS (Netherlands)

    Psarra, I.; Arentze, T.A.; Timmermans, H.J.P.

    2016-01-01

    This study focused on short-term dynamics of activity-travel behavior as a response to travel time increases. It is assumed that short-term changes are triggered by stress, which is defined as the deviation between an individual’s aspirations and his or her daily experiences. When stress exceeds a

  19. Predicting Short-Term Subway Ridership and Prioritizing Its Influential Factors Using Gradient Boosting Decision Trees

    Directory of Open Access Journals (Sweden)

    Chuan Ding

    2016-10-01

    Full Text Available Understanding the relationship between short-term subway ridership and its influential factors is crucial to improving the accuracy of short-term subway ridership prediction. Although there has been a growing body of studies on short-term ridership prediction approaches, limited effort is made to investigate the short-term subway ridership prediction considering bus transfer activities and temporal features. To fill this gap, a relatively recent data mining approach called gradient boosting decision trees (GBDT is applied to short-term subway ridership prediction and used to capture the associations with the independent variables. Taking three subway stations in Beijing as the cases, the short-term subway ridership and alighting passengers from its adjacent bus stops are obtained based on transit smart card data. To optimize the model performance with different combinations of regularization parameters, a series of GBDT models are built with various learning rates and tree complexities by fitting a maximum of trees. The optimal model performance confirms that the gradient boosting approach can incorporate different types of predictors, fit complex nonlinear relationships, and automatically handle the multicollinearity effect with high accuracy. In contrast to other machine learning methods—or “black-box” procedures—the GBDT model can identify and rank the relative influences of bus transfer activities and temporal features on short-term subway ridership. These findings suggest that the GBDT model has considerable advantages in improving short-term subway ridership prediction in a multimodal public transportation system.

  20. Effect of short-term hyperglycemia on cerebral function in neurooncological patients

    International Nuclear Information System (INIS)

    Loginov, V.M.; Gnezditskij, V.V.; Emulyushina, O.N.; Mukhamedzhanov, N.Z.

    1991-01-01

    The paper is concerned with the results of investigation of the effect of short-term hyperglycemia on main cerebral functions in 13 neurooncological patients. Taking into account good tolerance of short-term hyperglycemia and the results of its effective use in general oncology, one can recommend it as a modifier in radiation therapy of brain gliomas

  1. Effect of Short-Term Study Abroad Programs on Students' Cultural Adaptability

    Science.gov (United States)

    Mapp, Susan C.

    2012-01-01

    The number of U.S. students studying abroad has been growing, particularly those participating in short-term trips. However, literature on the effect of these short-term trips is lacking. The purpose of this study was to assess quantitatively the effect on bachelor students' cross-cultural adaptability using a pre-post design. Significant changes…

  2. What are the differences between long-term, short-term, and working memory?

    Science.gov (United States)

    Cowan, Nelson

    2008-01-01

    In the recent literature there has been considerable confusion about the three types of memory: long-term, short-term, and working memory. This chapter strives to reduce that confusion and makes up-to-date assessments of these types of memory. Long- and short-term memory could differ in two fundamental ways, with only short-term memory demonstrating (1) temporal decay and (2) chunk capacity limits. Both properties of short-term memory are still controversial but the current literature is rather encouraging regarding the existence of both decay and capacity limits. Working memory has been conceived and defined in three different, slightly discrepant ways: as short-term memory applied to cognitive tasks, as a multi-component system that holds and manipulates information in short-term memory, and as the use of attention to manage short-term memory. Regardless of the definition, there are some measures of memory in the short term that seem routine and do not correlate well with cognitive aptitudes and other measures (those usually identified with the term "working memory") that seem more attention demanding and do correlate well with these aptitudes. The evidence is evaluated and placed within a theoretical framework depicted in Fig. 1.

  3. Cash Management and Short-Term Investments for Colleges and Universities.

    Science.gov (United States)

    Haag, Leonard H.

    Effective cash management and short-term investing are discussed in this "how to" guide designed to benefit most institutions of higher education. The following premises are examined: proper compensation for effective cash management is not an expense but an investment; effective cash management and short-term investment programs do not depend on…

  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. Short-term forecasting of turbidity in trunk main networks.

    Science.gov (United States)

    Meyers, Gregory; Kapelan, Zoran; Keedwell, Edward

    2017-11-01

    Water discolouration is an increasingly important and expensive issue due to rising customer expectations, tighter regulatory demands and ageing Water Distribution Systems (WDSs) in the UK and abroad. This paper presents a new turbidity forecasting methodology capable of aiding operational staff and enabling proactive management strategies. The turbidity forecasting methodology developed here is completely data-driven and does not require hydraulic or water quality network model that is expensive to build and maintain. The methodology is tested and verified on a real trunk main network with observed turbidity measurement data. Results obtained show that the methodology can detect if discolouration material is mobilised, estimate if sufficient turbidity will be generated to exceed a preselected threshold and approximate how long the material will take to reach the downstream meter. Classification based forecasts of turbidity can be reliably made up to 5 h ahead although at the expense of increased false alarm rates. The methodology presented here could be used as an early warning system that can enable a multitude of cost beneficial proactive management strategies to be implemented as an alternative to expensive trunk mains cleaning programs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Expectations impact short-term memory through changes in connectivity between attention- and task-related brain regions.

    Science.gov (United States)

    Sinke, Christopher; Forkmann, Katarina; Schmidt, Katharina; Wiech, Katja; Bingel, Ulrike

    2016-05-01

    Over the recent years, neuroimaging studies have investigated the neural mechanisms underlying the influence of expectations on perception. However, it seems equally reasonable to assume that expectations impact cognitive functions. Here we used fMRI to explore the role of expectations on task performance and its underlying neural mechanisms. 43 healthy participants were randomly assigned to two groups. Using verbal instructions, group 1 was led to believe that pain enhances task performance while group 2 was instructed that pain hampers their performance. All participants performed a Rapid-Serial-Visual-Presentation (RSVP) Task (target detection and short-term memory component) with or without concomitant painful heat stimulation during 3T fMRI scanning. As hypothesized, short-term memory performance showed an interaction between painful stimulation and expectation. Positive expectations induced stronger neural activation in the right inferior parietal cortex (IPC) during painful stimulation than negative expectation. Moreover, IPC displayed differential functional coupling with the left inferior occipital cortex under pain as a function of expectancy. Our data show that an individual's expectation can influence cognitive performance in a visual short-term memory task which is associated with activity and connectivity changes in brain areas implicated in attentional processing and task performance. Copyright © 2016. Published by Elsevier Ltd.

  7. Synaptic plasticity, neural circuits, and the emerging role of altered short-term information processing in schizophrenia

    Science.gov (United States)

    Crabtree, Gregg W.; Gogos, Joseph A.

    2014-01-01

    Synaptic plasticity alters the strength of information flow between presynaptic and postsynaptic neurons and thus modifies the likelihood that action potentials in a presynaptic neuron will lead to an action potential in a postsynaptic neuron. As such, synaptic plasticity and pathological changes in synaptic plasticity impact the synaptic computation which controls the information flow through the neural microcircuits responsible for the complex information processing necessary to drive adaptive behaviors. As current theories of neuropsychiatric disease suggest that distinct dysfunctions in neural circuit performance may critically underlie the unique symptoms of these diseases, pathological alterations in synaptic plasticity mechanisms may be fundamental to the disease process. Here we consider mechanisms of both short-term and long-term plasticity of synaptic transmission and their possible roles in information processing by neural microcircuits in both health and disease. As paradigms of neuropsychiatric diseases with strongly implicated risk genes, we discuss the findings in schizophrenia and autism and consider the alterations in synaptic plasticity and network function observed in both human studies and genetic mouse models of these diseases. Together these studies have begun to point toward a likely dominant role of short-term synaptic plasticity alterations in schizophrenia while dysfunction in autism spectrum disorders (ASDs) may be due to a combination of both short-term and long-term synaptic plasticity alterations. PMID:25505409

  8. Intensive short-term vasodilation effect in the pain area of sciatica patients--case study.

    Science.gov (United States)

    Skorupska, Elżbieta; Rychlik, Michał; Pawelec, Wiktoria; Bednarek, Agata; Samborski, Włodzimierz

    2014-09-09

    Varied and complicated etiology of low back pain radiating distally to the extremities is still causing disagreement and controversy around the issue of its diagnosis and treatment. Most clinicians believe that the source of that pain is generally radicular. While some of them postulate the clinical significance of the sacroiliac joint syndrome, others demonstrate that almost one in five people with back pain experience symptoms indicative of the neuropathic pain component. To date, neuropathic involvement has not been completely understood, and different mechanisms are thought to play an important role. It has been established that muscle pain (myofascial pain) e.g. active trigger points from the gluteus minimus, can mimic pain similar to sciatica, especially in the chronic stage. This paper describes patients presenting with radicular sciatica (case one and two) and sciatica-like symptoms (case three). For the first time, intensive short-term vasodilation in the pain area following needle infiltration of the gluteus minimus trigger point was recorded. Three Caucasian, European women suffering from radicular sciatica (case one and two) and sciatica-like symptoms (case three) at the age of 57, 49 and 47 respectively underwent infrared camera observation during needle infiltration of the gluteus minimus trigger point. The patients were diagnosed by a neurologist; they underwent magnetic resonance imaging, electromyography, neurography and blood test analysis. Apart from that, the patients were diagnosed by a clinician specializing in myofascial pain diagnosis. In the examined cases, trigger points-related short-term vasodilation was recorded. Confirmation of these findings in a controlled, blinded study would indicate the existence of a link between the pain of sciatica patients (radicular or sciatica-like pain) and the activity of the autonomic nervous system. Further studies on a bigger group of patients are still needed.

  9. [Short-term outcomes of lung transplant recipients using organs from brain death donors].

    Science.gov (United States)

    He, W X; Jiang, C; Liu, X G; Huang, W; Chen, C; Jiang, L; Yang, B; Wu, K; Chen, Q K; Yang, Y; Yu, Y M; Jiang, G N

    2016-12-01

    Objective: To assess short-term outcomes after lung transplantation with organs procured following brain death. Methods: Between April 2015 and July 2016, all 17 recipients after lung transplantation using organs from brain death donors (DBD) at Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine were enrolled in this study. All patients were male, aging (60±7) years, including 11 chronic obstructive pulmonary disease, 5 idiopathic pulmonary fibrosis, 1 silicosis. Seventeen donors were 16 males and 1 female, with 10 traumatic brain injury, 5 cerebrovascular accident and 2 sudden cardiac death. Of 17 recipients receiving DBD lung transplant, 16 were single lung transplant. Data were collected including intubation duration of mechanical ventilation, hospital length of stay, incidence of pulmonary infection bronchus anastomosis complications, primary graft dysfunction (PGD), and acute rejection, bronchiolitis obliterans syndrome (BOS) as well as mortality of 90-day after lung transplantation. Results: Median duration of intubation were 2 (2) days ( M ( Q R )) in recipients after lung transplantation. The incidence of pulmonary infection and bronchus anastomosis complications were 15/17 and 5/17, respectively. Median length of stay in hospital were 56 (19) days. The ratio of readmission 1 month after discharge were 10/17. Mortality of 90-day post-transplant were 2/17. The incidence of PGD and BOS were 1/17 and 2/17, respectively. Conclusion: Recipients with DBD lung transplantation have an acceptable survival during short-term follow-up, but with higher incidences of complications related to infection post-transplantation.

  10. Cerebral atrophy as outcome measure in short-term phase 2 clinical trials in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Elskamp, I.J. van den; Boden, B.; Barkhof, F. [VU University Medical Center, Department of Radiology, MS Center Amsterdam, Amsterdam (Netherlands); Dattola, V. [VU University Medical Center, Department of Radiology, MS Center Amsterdam, Amsterdam (Netherlands); University of Messina, Department of Neurosciences, Psychiatric and Anaesthesiological Sciences, Messina (Italy); Knol, D.L. [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Filippi, M. [Scientific Institute and University Ospedale San Raffaele, Neuroimaging Research Unit, Milan (Italy); Kappos, L. [University Hospital, University of Basel, Department of Neurology, Basel (Switzerland); Fazekas, F. [Medical University of Graz, Department of Neurology, Graz (Austria); Wagner, K. [Bayer-Schering Pharma, Berlin (Germany); Pohl, C. [Bayer-Schering Pharma, Berlin (Germany); University Hospital Bonn, Department of Neurology, Bonn (Germany); Sandbrink, R. [Bayer-Schering Pharma, Berlin (Germany); Heinrich-Heine-University Dusseldorf, Department of Neurology, Dusseldorf (Germany); Polman, C.H. [VU University Medical Center, Department of Neurology, MS Center Amsterdam, Amsterdam (Netherlands); Uitdehaag, B.M.J. [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); VU University Medical Center, Department of Neurology, MS Center Amsterdam, Amsterdam (Netherlands)

    2010-10-15

    Cerebral atrophy is a compound measure of the neurodegenerative component of multiple sclerosis (MS) and a conceivable outcome measure for clinical trials monitoring the effect of neuroprotective agents. In this study, we evaluate the rate of cerebral atrophy in a 6-month period, investigate the predictive and explanatory value of other magnetic resonance imaging (MRI) measures in relation to cerebral atrophy, and determine sample sizes for future short-term clinical trials using cerebral atrophy as primary outcome measure. One hundred thirty-five relapsing-remitting multiple sclerosis patients underwent six monthly MRI scans from which the percentage brain volume change (PBVC) and the number and volume of gadolinium (Gd)-enhancing lesions, T2 lesions, and persistent black holes (PBH) were determined. By means of multiple linear regression analysis, the relationship between focal MRI variables and PBVC was assessed. Sample size calculations were performed for all patients and subgroups selected for enhancement or a high T2 lesion load at baseline. A significant atrophy occurred over 6 months (PBVC = -0.33%, SE = 0.061, p < 0.0001). The number of baseline T2 lesions (p = 0.024), the on-study Gd-enhancing lesion volume (p = 0.044), and the number of on-study PBHs (p = 0.003) were associated with an increased rate of atrophy. For a 50% decrease in rate of atrophy, the sample size calculations showed that approximately 283 patients per arm are required in an unselected sampled population and 185 patients per arm are required in a selected population. Within a 6-month period, significant atrophy can be detected and on-study associations of PBVC and PBHs emphasizes axonal loss to be a driving mechanism. Application as primary outcome measure in short-term clinical trials with feasible sample size requires a potent drug to obtain sufficient power. (orig.)

  11. Short-term immobilization influences use-dependent cortical plasticity and fine motor performance.

    Science.gov (United States)

    Opie, George M; Evans, Alexandra; Ridding, Michael C; Semmler, John G

    2016-08-25

    Short-term immobilization that reduces muscle use for 8-10h is known to influence cortical excitability and motor performance. However, the mechanisms through which this is achieved, and whether these changes can be used to modify cortical plasticity and motor skill learning, are not known. The purpose of this study was to investigate the influence of short-term immobilization on use-dependent cortical plasticity, motor learning and retention. Twenty-one adults were divided into control and immobilized groups, both of which underwent two experimental sessions on consecutive days. Within each session, transcranial magnetic stimulation (TMS) was used to assess motor-evoked potential (MEP) amplitudes, short- (SICI) and long-interval intracortical inhibition (LICI), and intracortical facilitation (ICF) before and after a grooved pegboard task. Prior to the second training session, the immobilized group underwent 8h of left hand immobilization targeting the index finger, while control subjects were allowed normal limb use. Immobilization produced a reduction in MEP amplitudes, but no change in SICI, LICI or ICF. While motor performance improved for both groups in each session, the level of performance was greater 24-h later in control, but not immobilized subjects. Furthermore, training-related MEP facilitation was greater after, compared with before, immobilization. These results indicate that immobilization can modulate use-dependent plasticity and the retention of motor skills. They also suggest that changes in intracortical excitability are unlikely to contribute to the immobilization-induced modification of cortical excitability. Copyright © 2016. Published by Elsevier Ltd.

  12. Short term memory for single surface features and bindings in ageing: A replication study.

    Science.gov (United States)

    Isella, Valeria; Molteni, Federica; Mapelli, Cristina; Ferrarese, Carlo

    2015-06-01

    In the present study we replicated a previous experiment investigating visuo-spatial short term memory binding in young and older healthy individuals, in the attempt to verify the pattern of impairment that can be observed in normal elderly for short term memory for single items vs short term memory for bindings. Assessing a larger sample size (25 young and 25 older subjects), using a more appropriate measure of accuracy for a change detection task (A'), and adding the evaluation of speed of performance, we confirmed that old normals show a decline in short term memory for bindings of shape and colour that is of comparable extent, and not major, to the decline in memory for single shapes and single colours. The absence of a specific deficit of short term memory for conjunctions of surface features seems to distinguish cognitive ageing from Alzheimer's Disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Qualitative similarities in the visual short-term memory of pigeons and people.

    Science.gov (United States)

    Gibson, Brett; Wasserman, Edward; Luck, Steven J

    2011-10-01

    Visual short-term memory plays a key role in guiding behavior, and individual differences in visual short-term memory capacity are strongly predictive of higher cognitive abilities. To provide a broader evolutionary context for understanding this memory system, we directly compared the behavior of pigeons and humans on a change detection task. Although pigeons had a lower storage capacity and a higher lapse rate than humans, both species stored multiple items in short-term memory and conformed to the same basic performance model. Thus, despite their very different evolutionary histories and neural architectures, pigeons and humans have functionally similar visual short-term memory systems, suggesting that the functional properties of visual short-term memory are subject to similar selective pressures across these distant species.

  14. Structural imprints in vivo decode RNA regulatory mechanisms.

    Science.gov (United States)

    Spitale, Robert C; Flynn, Ryan A; Zhang, Qiangfeng Cliff; Crisalli, Pete; Lee, Byron; Jung, Jong-Wha; Kuchelmeister, Hannes Y; Batista, Pedro J; Torre, Eduardo A; Kool, Eric T; Chang, Howard Y

    2015-03-26

    Visualizing the physical basis for molecular behaviour inside living cells is a great challenge for biology. RNAs are central to biological regulation, and the ability of RNA to adopt specific structures intimately controls every step of the gene expression program. However, our understanding of physiological RNA structures is limited; current in vivo RNA structure profiles include only two of the four nucleotides that make up RNA. Here we present a novel biochemical approach, in vivo click selective 2'-hydroxyl acylation and profiling experiment (icSHAPE), which enables the first global view, to our knowledge, of RNA secondary structures in living cells for all four bases. icSHAPE of the mouse embryonic stem cell transcriptome versus purified RNA folded in vitro shows that the structural dynamics of RNA in the cellular environment distinguish different classes of RNAs and regulatory elements. Structural signatures at translational start sites and ribosome pause sites are conserved from in vitro conditions, suggesting that these RNA elements are programmed by sequence. In contrast, focal structural rearrangements in vivo reveal precise interfaces of RNA with RNA-binding proteins or RNA-modification sites that are consistent with atomic-resolution structural data. Such dynamic structural footprints enable accurate prediction of RNA-protein interactions and N(6)-methyladenosine (m(6)A) modification genome wide. These results open the door for structural genomics of RNA in living cells and reveal key physiological structures controlling gene expression.

  15. Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [ORNL; Olama, Mohammed M. [ORNL; Dong, Jin [ORNL; Djouadi, Seddik M. [ORNL; Zhang, Yichen [University of Tennessee, Knoxville (UTK), Department of Electrical Engineering and Computer Science

    2017-09-01

    The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed to estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.

  16. Upregulation of transcription factor NRF2-mediated oxidative stress response pathway in rat brain under short-term chronic hypobaric hypoxia.

    Science.gov (United States)

    Sethy, Niroj Kumar; Singh, Manjulata; Kumar, Rajesh; Ilavazhagan, Govindasamy; Bhargava, Kalpana

    2011-03-01

    Exposure to high altitude (and thus hypobaric hypoxia) induces electrophysiological, metabolic, and morphological modifications in the brain leading to several neurological clinical syndromes. Despite the known fact that hypoxia episodes in brain are a common factor for many neuropathologies, limited information is available on the underlying cellular and molecular mechanisms. In this study, we investigated the temporal effect of short-term (0-12 h) chronic hypobaric hypoxia on global gene expression of rat brain followed by detailed canonical pathway analysis and regulatory network identification. Our analysis revealed significant alteration of 33, 17, 53, 81, and 296 genes (p stress response pathway and genes were detected at all time points suggesting activation of NRF2-ARE antioxidant defense system. The results were further validated by assessing the expression levels of selected genes in temporal as well as brain regions with quantitative RT-PCR and western blot. In conclusion, our whole brain approach with temporal monitoring of gene expression patterns during hypobaric hypoxia has resulted in (1) deciphering sequence of pathways and signaling networks activated during onset of hypoxia, and (2) elucidation of NRF2-orchestrated antioxidant response as a major intrinsic defense mechanism. The results of this study will aid in better understanding and management of hypoxia-induced brain pathologies.

  17. The Role of Short-Term Memory in Operator Workload

    Science.gov (United States)

    1988-04-01

    Craik , F.I. and Lockhart , R.S., 1972, Levels of processing : A framework for memory research...examples of postcategorical selction models. Precategorical Selection Models Sperling’s Model. Unlike Craik and Lockhart’s levels -of- processing model...subdivided to contain a primary memory unit and a mechanism for the direction of conscious attention. Levels -of- Processing . Craik and Lockhart’s levels

  18. Global Lightning Response to Forbush Decreases in Short-term

    Science.gov (United States)

    Li, H.; Wu, Q.; Wang, C.

    2017-12-01

    During the past three decades, particular scientific attention has been drawn to the potential link between solar activities and global climate change. How the sun modulates the climate has always been controversial. There are three relatively widely accepted mechanisms illustrating this process: the total solar irradiance (TSI), the solar ultraviolet radiation (SUR), and the space weather mechanisms. As for space weather mechanism, the sun influences the microphysical process in cloud by modulating the cosmic ray flux and thus changes the cloud cover, which finally affects the earth's radiation balance. Unfortunately, the lack of related observations and some opposite research results make this mechanism rather debatable. In order to provide possible evidence for space weather mechanism, we study the influence of Forbush decreases (FDs) of galactic cosmic ray on global lightning activities, which to some extent represents the basic process of cosmic ray-atmospheric coupling. We use the daily lightning counts from 1998 to 2014 observed by LIS sensor aboard the TRMM satellite. Considering the "diurnal distribution" (occurring more in the afternoon than in the morning) and the "seasonal distribution" (occurring more in summer than in winter) of lightning activities as well as the 49-day precession of TRMM satellite, the daily lightning counts show an intricate periodic fluctuation. We propose a 3-step approach - latitude zone limitation, orbit branch selection and local time normalization - to eliminate it. As for FDs, we select them by checking the hourly neutron counts variation of each month of 17 years obtained from the Oulu Cosmic Ray Station. During the selection, we choose the FDs which are "strong" (decrease more than 6%) and "standard" (strongly decrease in a few hours to one day and gradually recover in about one week) to diminish the meteorological influence and other possible disturbance. For both case study and temporal superposition of several cases

  19. Genetic control and regulatory mechanisms of succinoglycan and curdlan biosynthesis in genus Agrobacterium.

    Science.gov (United States)

    Wu, Dan; Li, Ang; Ma, Fang; Yang, Jixian; Xie, Yutong

    2016-07-01

    Agrobacterium is a genus of gram-negative bacteria that can produce several typical exopolysaccharides with commercial uses in the food and pharmaceutical fields. In particular, succinoglycan and curdlan, due to their good quality in high yield, have been employed on an industrial scale comparatively early. Exopolysaccharide biosynthesis is a multiple-step process controlled by different functional genes, and various environmental factors cause changes in exopolysaccharide biosynthesis through regulatory mechanisms. In this mini-review, we focus on the genetic control and regulatory mechanisms of succinoglycan and curdlan produced by Agrobacterium. Some key functional genes and regulatory mechanisms for exopolysaccharide biosynthesis are described, possessing a high potential for application in metabolic engineering to modify exopolysaccharide production and physicochemical properties. This review may contribute to the understanding of exopolysaccharide biosynthesis and exopolysaccharide modification by metabolic engineering methods in Agrobacterium.

  20. Behavioural ratings of self-regulatory mechanisms and driving behaviour after an acquired brain injury.

    Science.gov (United States)

    Rike, Per-Ola; Ulleberg, Pål; Schultheis, Maria T; Lundqvist, Anna; Schanke, Anne-Kristine

    2014-01-01

    To explore whether measurements of self-regulatory mechanisms and cognition predict driving behaviour after an acquired brain injury (ABI). Consecutive follow-up study. At baseline participants included 77 persons with stroke and 32 persons with a traumatic brain injury (TBI), all of whom completed a multidisciplinary driving assessment (MDA). A follow-up cohort of 34 persons that succeeded the MDA was included. Baseline measurements: Neuropsychological tests and measurements of self-regulatory mechanisms (BRIEF-A and UPPS Impulsive Behaviour Scale), driving behaviour (DBQ) and pre-injury driving characteristics (mileage, compensatory driving strategies and accident rates). Follow-up measurements: Post-injury driving characteristics were collected by mailed questionnaires from the participants who succeeded the MDA. A MDA, which included a medical examination, neuropsychological testing and an on-road driving test, was considered in the decision for or against granting a driver's license. Self-regulatory mechanisms and driving behaviour were examined for research purposes only. At baseline, self-regulatory mechanisms were significantly associated to aberrant driving behaviour, but not with neuropsychological data or with the outcome of the on-road driving test. Aspects of self-regulation were associated to driving behaviour at follow-up. It is recommended that self-regulatory measurements should regularly be considered in the driving assessments after ABI.

  1. The beginning of a seed: regulatory mechanisms of double fertilization.

    Science.gov (United States)

    Bleckmann, Andrea; Alter, Svenja; Dresselhaus, Thomas

    2014-01-01

    THE LAUNCH OF SEED DEVELOPMENT IN FLOWERING PLANTS (ANGIOSPERMS) IS INITIATED BY THE PROCESS OF DOUBLE FERTILIZATION: two male gametes (sperm cells) fuse with two female gametes (egg and central cell) to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube toward the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy) to maximize their reproductive success.

  2. Glucose Homeostasis During Short-term and Prolonged Exposure to High Altitudes

    Science.gov (United States)

    Ader, Marilyn; Bergman, Richard N.

    2015-01-01

    Most of the literature related to high altitude medicine is devoted to the short-term effects of high-altitude exposure on human physiology. However, long-term effects of living at high altitudes may be more important in relation to human disease because more than 400 million people worldwide reside above 1500 m. Interestingly, individuals living at higher altitudes have a lower fasting glycemia and better glucose tolerance compared with those who live near sea level. There is also emerging evidence of the lower prevalence of both obesity and diabetes at higher altitudes. The mechanisms underlying improved glucose control at higher altitudes remain unclear. In this review, we present the most current evidence about glucose homeostasis in residents living above 1500 m and discuss possible mechanisms that could explain the lower fasting glycemia and lower prevalence of obesity and diabetes in this population. Understanding the mechanisms that regulate and maintain the lower fasting glycemia in individuals who live at higher altitudes could lead to new therapeutics for impaired glucose homeostasis. PMID:25675133

  3. Transcriptome Profiling of Watermelon Root in Response to Short-Term Osmotic Stress.

    Science.gov (United States)

    Yang, Yongchao; Mo, Yanling; Yang, Xiaozheng; Zhang, Haifei; Wang, Yongqi; Li, Hao; Wei, Chunhua; Zhang, Xian

    2016-01-01

    Osmotic stress adversely affects the growth, fruit quality and yield of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai). Increasing the tolerance of watermelon to osmotic stress caused by factors such as high salt and water deficit is an effective way to improve crop survival in osmotic stress environments. Roots are important organs in water absorption and are involved in the initial response to osmosis stress; however, few studies have examined the underlying mechanism of tolerance to osmotic stress in watermelon roots. For better understanding of this mechanism, the inbred watermelon accession M08, which exhibits relatively high tolerance to water deficits, was treated with 20% polyethylene glycol (PEG) 6000. The root samples were harvested at 6 h after PEG treatment and untreated samples were used as controls. Transcriptome analyses were carried out by Illumina RNA sequencing. A total of 5246 differentially expressed genes were identified. Gene ontology enrichment and biochemical pathway analyses of these 5246 genes showed that short-term osmotic stress affected osmotic adjustment, signal transduction, hormone responses, cell division, cell cycle and ribosome, and M08 may repress root growth to adapt osmotic stress. The results of this study describe the watermelon root transcriptome under osmotic stress and propose new insight into watermelon root responses to osmotic stress at the transcriptome level. Accordingly, these results allow us to better understand the molecular mechanisms of watermelon in response to drought stress and will facilitate watermelon breeding projects to improve drought tolerance.

  4. Consequence of preterm birth in early adolescence: the role of language on auditory short-term memory.

    Science.gov (United States)

    Fraello, David; Maller-Kesselman, Jill; Vohr, Betty; Katz, Karol H; Kesler, Shelli; Schneider, Karen; Reiss, Allan; Ment, Laura; Spann, Marisa N

    2011-06-01

    This study tested the hypothesis that preterm early adolescents' short-term memory is compromised when presented with increasingly complex verbal information and that associated neuroanatomical volumes would differ between preterm and term groups. Forty-nine preterm and 20 term subjects were evaluated at age 12 years with neuropsychological measures and magnetic resonance imaging (MRI). There were no differences between groups in simple short-term and working memory. Preterm subjects performed lower on learning and short-term memory tests that included increased verbal complexity. They had reduced right parietal, left temporal, and right temporal white matter volumes and greater bilateral frontal gray and right frontal white matter volumes. There was a positive association between complex working memory and the left hippocampus and frontal white matter in term subjects. While not correlated, memory scores and volumes of cortical regions known to subserve language and memory were reduced in preterm subjects. This study provides evidence of possible mechanisms for learning problems in former preterm infants.

  5. MEMANTINE ATTENUATES THE OKADAIC ACID INDUCED SHORT-TERM SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS IN RATS.

    Science.gov (United States)

    Dashniani, M; Chighladze, M; Burjanadze, M; Beselia, G; Kruashvili, L

    2016-03-01

    In the present study, the possible beneficial effect of memantine on the Okadaic Acid (OA) induced spatial short-term memory impairment was examined in spatial alternation task, and the neuroprotective potential of memantine on OA-induced structural changes in the hippocampus was evaluated by Nissl staining. OA was dissolved in artificial cerebrospinal fluid (aCSF) and injected intracerebroventriculary (ICV) 200 ng in a volume of 10 μl bilaterally. Vehicle control received aCSF ICV bilaterally. Control and OA injected rats were divided into 2 subgroups injected i.p. with saline or memantine (5 mg/kg). Memantine or saline were given daily for 13 days starting from the day of OA injection. Behavioral study showed that bilateral ICV microinjection of OA induced impairment in spatial short-term memory. Nissl staining in the present study showed that the ICV microinjection of OA significantly decreased the number of surviving pyramidal neurons in the CA1 region of the hippocampus. Chronic administration of memantine effectively attenuated OA induced spatial short-term memory impairment and the OA-induced neuropathological changes in the hippocampus. Therefore, ICV injection of OA can be used as an experimental model to study mechanisms of neurodegeneration and define novel therapeutics targets for AD pathology.

  6. Short-term memory of motor network performance via activity-dependent potentiation of Na+/K+ pump function.

    Science.gov (United States)

    Zhang, Hong-Yan; Sillar, Keith T

    2012-03-20

    Brain networks memorize previous performance to adjust their output in light of past experience. These activity-dependent modifications generally result from changes in synaptic strengths or ionic conductances, and ion pumps have only rarely been demonstrated to play a dynamic role. Locomotor behavior is produced by central pattern generator (CPG) networks and modified by sensory and descending signals to allow for changes in movement frequency, intensity, and duration, but whether or how the CPG networks recall recent activity is largely unknown. In Xenopus frog tadpoles, swim bout duration correlates linearly with interswim interval, suggesting that the locomotor network retains a short-term memory of previous output. We discovered an ultraslow, minute-long afterhyperpolarization (usAHP) in network neurons following locomotor episodes. The usAHP is mediated by an activity- and sodium spike-dependent enhancement of electrogenic Na(+)/K(+) pump function. By integrating spike frequency over time and linking the membrane potential of spinal neurons to network performance, the usAHP plays a dynamic role in short-term motor memory. Because Na(+)/K(+) pumps are ubiquitously expressed in neurons of all animals and because sodium spikes inevitably accompany network activity, the usAHP may represent a phylogenetically conserved but largely overlooked mechanism for short-term memory of neural network function. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Variation in Parasympathetic Dysregulation Moderates Short-term Memory Problems in Childhood Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Ward, Anthony R; Alarcón, Gabriela; Nigg, Joel T; Musser, Erica D

    2015-11-01

    Although attention deficit/hyperactivity disorder (ADHD) is associated with impairment in working memory and short-term memory, up to half of individual children with ADHD perform within a normative range. Heterogeneity in other ADHD-related mechanisms, which may compensate for or combine with cognitive weaknesses, is a likely explanation. One candidate is the robustness of parasympathetic regulation (as indexed by respiratory sinus arrhythmia; RSA). Theory and data suggest that a common neural network is likely tied to both heart-rate regulation and certain cognitive functions (including aspects of working and short-term memory). Cardiac-derived indices of parasympathetic reactivity were collected during short-term memory (STM) storage and rehearsal tasks from 243 children (116 ADHD, 127 controls). ADHD was associated with lower STM performance, replicating previous work. In addition, RSA reactivity moderated the association between STM and ADHD - both as a category and a dimension - independent of comorbidity. Specifically, conditional effects revealed that high levels of withdrawal interacted with weakened STM but high levels of augmentation moderated a positive association predicting ADHD. Thus, variations in parasympathetic reactivity may help explain neuropsychological heterogeneity in ADHD.

  8. Neuroticism and conscientiousness respectively constrain and facilitate short-term plasticity within the working memory neural network.

    Science.gov (United States)

    Dima, Danai; Friston, Karl J; Stephan, Klaas E; Frangou, Sophia

    2015-10-01

    Individual differences in cognitive efficiency, particularly in relation to working memory (WM), have been associated both with personality dimensions that reflect enduring regularities in brain configuration, and with short-term neural plasticity, that reflects task-related changes in brain connectivity. To elucidate the relationship of these two divergent mechanisms, we tested the hypothesis that personality dimensions, which reflect enduring aspects of brain configuration, inform about the neurobiological framework within which short-term, task-related plasticity, as measured by effective connectivity, can be facilitated or constrained. As WM consistently engages the dorsolateral prefrontal (DLPFC), parietal (PAR), and anterior cingulate cortex (ACC), we specified a WM network model with bidirectional, ipsilateral, and contralateral connections between these regions from a functional magnetic resonance imaging dataset obtained from 40 healthy adults while performing the 3-back WM task. Task-related effective connectivity changes within this network were estimated using Dynamic Causal Modelling. Personality was evaluated along the major dimensions of Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Only two dimensions were relevant to task-dependent effective connectivity. Neuroticism and Conscientiousness respectively constrained and facilitated neuroplastic responses within the WM network. These results suggest individual differences in cognitive efficiency arise from the interplay between enduring and short-term plasticity in brain configuration. © 2015 Wiley Periodicals, Inc.

  9. Cardiac complications associated with short-term mortality in schizophrenia patients hospitalized for pneumonia: a nationwide case-control study.

    Directory of Open Access Journals (Sweden)

    Ya-Tang Liao

    Full Text Available BACKGROUND: Pneumonia is one of most prevalent infectious diseases worldwide and is associated with considerable mortality. In comparison to general population, schizophrenia patients hospitalized for pneumonia have poorer outcomes. We explored the risk factors of short-term mortality in this population because the information is lacking in the literature. METHODS: In a nationwide schizophrenia cohort, derived from the National Health Insurance Research Database in Taiwan, that was hospitalized for pneumonia between 2000 and 2008 (n = 1,741, we identified 141 subjects who died during their hospitalizations or shortly after their discharges. Based on risk-set sampling in a 1∶4 ratio, 468 matched controls were selected from the study cohort (i.e., schizophrenia cohort with pneumonia. Physical illnesses were categorized as pre-existing and incident illnesses that developed after pneumonia respectively. Exposures to medications were categorized by type, duration, and defined daily dose. We used stepwise conditional logistic regression to explore the risk factors for short-term mortality. RESULTS: Pre-existing arrhythmia was associated with short-term mortality (adjusted risk ratio [RR] = 4.99, p<0.01. Several variables during hospitalization were associated with increased mortality risk, including incident arrhythmia (RR = 7.44, p<0.01, incident heart failure (RR = 5.49, p = 0.0183 and the use of hypoglycemic drugs (RR = 2.32, p<0.01. Furthermore, individual antipsychotic drugs (such as clozapine known to induce pneumonia were not significantly associated with the risk. CONCLUSIONS: Incident cardiac complications following pneumonia are associated with increased short-term mortality. These findings have broad implications for clinical intervention and future studies are needed to clarify the mechanisms of the risk factors.

  10. Understanding phonological memory deficits in boys with attention-deficit/hyperactivity disorder (ADHD): dissociation of short-term storage and articulatory rehearsal processes.

    Science.gov (United States)

    Bolden, Jennifer; Rapport, Mark D; Raiker, Joseph S; Sarver, Dustin E; Kofler, Michael J

    2012-08-01

    The current study dissociated and examined the two primary components of the phonological working memory subsystem--the short-term store and articulatory rehearsal mechanism--in boys with ADHD (n = 18) relative to typically developing boys (n = 15). Word lists of increasing length (2, 4, and 6 words per trial) were presented to and recalled by children following a brief (3 s) interval to assess their phonological short-term storage capacity. Children's ability to utilize the articulatory rehearsal mechanism to actively maintain information in the phonological short-term store was assessed using word lists at their established memory span but with extended rehearsal times (12 s and 21 s delays). Results indicate that both phonological shortterm storage capacity and articulatory rehearsal are impaired or underdeveloped to a significant extent in boys with ADHD relative to typically developing boys, even after controlling for age, SES, IQ, and reading speed. Larger magnitude deficits, however, were apparent in short-term storage capacity (ES = 1.15 to 1.98) relative to articulatory rehearsal (ES = 0.47 to 1.02). These findings are consistent with previous reports of deficient phonological short-term memory in boys with ADHD, and suggest that future attempts to develop remedial cognitive interventions for children with ADHD will need to include active components that require children to hold increasingly more information over longer time intervals.

  11. Attention biases visual activity in visual short-term memory.

    Science.gov (United States)

    Kuo, Bo-Cheng; Stokes, Mark G; Murray, Alexandra M; Nobre, Anna Christina

    2014-07-01

    In the current study, we tested whether representations in visual STM (VSTM) can be biased via top-down attentional modulation of visual activity in retinotopically specific locations. We manipulated attention using retrospective cues presented during the retention interval of a VSTM task. Retrospective cues triggered activity in a large-scale network implicated in attentional control and led to retinotopically specific modulation of activity in early visual areas V1-V4. Importantly, shifts of attention during VSTM maintenance were associated with changes in functional connectivity between pFC and retinotopic regions within V4. Our findings provide new insights into top-down control mechanisms that modulate VSTM representations for flexible and goal-directed maintenance of the most relevant memoranda.

  12. Dissociating Contents of Consciousness from Contents of Short-Term Memory

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Ásgeirsson, Árni Gunnar; Staugaard, Camilla Funch

    2014-01-01

    The contents of consciousness and of short-term memory are hard to disentangle. As it seems intuitive that we represent attended objects in short-term memory and in experience, to many, it also seems intuitive to equate this content. Here we investigated memory resolution for orientation......” to a “clear experience” of a probed target. To assess memory resolution we used a Landolt-variation on the visual short-term memory (VSTM) resolution paradigm (e.g. Wilken & Ma, 2004). Set-sizes in the memory display were varied between 1, 2, or 4 elements. With increasing set-size we found that both...

  13. Selective potentiation of the antitumor radiation effect by means of short-term hyperglycemia

    International Nuclear Information System (INIS)

    Yarmonenko, S.P.; Shapot, V.S.; Voloshina, E.A.; Gorozhanskaya, Eh.G.; Dyuskaliev, Zh.D.; Krimker, V.M.

    1981-01-01

    Experiments on mice have shown that short-term induced hyperglycemia caused by 5-fold intraperitoneal administration of glucose at a dose of 2.6 and 1.3 g/kg increases notably the radiation injury to a solid type of Ehrlich carcinoma. Short-term induced hyperglycemia is mostly effective after irradiation. During irradiation together with its antitumor effect enhanced in the presence of short-term induced hyperglycemia there is observed selective protection of the normal tissues resulting from a decrease of oxygen pressure in them

  14. Attention Problems, Phonological Short-Term Memory, and Visuospatial Short-Term Memory: Differential Effects on Near- and Long-Term Scholastic Achievement

    Science.gov (United States)

    Sarver, Dustin E.; Rapport, Mark D.; Kofler, Michael J.; Scanlan, Sean W.; Raiker, Joseph S.; Altro, Thomas A.; Bolden, Jennifer

    2012-01-01

    The current study examined individual differences in children's phonological and visuospatial short-term memory as potential mediators of the relationship among attention problems and near- and long-term scholastic achievement. Nested structural equation models revealed that teacher-reported attention problems were associated negatively with…

  15. A Probabilistic Palimpsest Model of Visual Short-term Memory

    Science.gov (United States)

    Matthey, Loic; Bays, Paul M.; Dayan, Peter

    2015-01-01

    Working memory plays a key role in cognition, and yet its mechanisms remain much debated. Human performance on memory tasks is severely limited; however, the two major classes of theory explaining the limits leave open questions about key issues such as how multiple simultaneously-represented items can be distinguished. We propose a palimpsest model, with the occurrent activity of a single population of neurons coding for several multi-featured items. Using a probabilistic approach to storage and recall, we show how this model can account for many qualitative aspects of existing experimental data. In our account, the underlying nature of a memory item depends entirely on the characteristics of the population representation, and we provide analytical and numerical insights into critical issues such as multiplicity and binding. We consider representations in which information about individual feature values is partially separate from the information about binding that creates single items out of multiple features. An appropriate balance between these two types of information is required to capture fully the different types of error seen in human experimental data. Our model provides the first principled account of misbinding errors. We also suggest a specific set of stimuli designed to elucidate the representations that subjects actually employ. PMID:25611204

  16. Short term post-partum heat stress in dairy cows

    Science.gov (United States)

    Fuquay, J. W.; Chapin, L. T.; Brown, W. H.

    1980-06-01

    Since many dairy cows calve during late summer, the objective was to determine if heat stress immediately post-partum would (1) alter metabolism, thus, increasing susceptibility to metabolic disorders, (2) affect lactation and/or (3) affect reproduction. Forty four cows, calving during late summer, were paired with one member of each pair stressed (HS) for the first 10 post-partum days in a hot barn. Controls (CC) were kept in a cooled section of the barn. Plasma drawn weekly for 7 weeks was analyzed in an autoanalyzer for calcium, inor. phosphorus, protein, glucose and cholesterol and by radioimmunoassay for cortisol and progesterone. Ovaries and uteri were palpated weekly. Rectal temperatures were significant higher for HS during the first 10 post-partum days. No significant effects on plasma constituents were observed during the 10-day treatment period. For the 7-week period, glucose and cholesterol were lower in HS, as were cyclic peaks of progesterone and cortisol. Both calcium and inorganic phosphorus remained clinically low for the 7 weeks, but no treatment effects were seen. Uteri of HS involuted more rapidly than the CC. Treatment did not affect reproductive efficiency. Lactation milk yields did not differ, but milk fat percent was lower in HS. Heat stress immediately post-partum altered lipid metabolism, but the animal's compensatory mechanisms prevented reduction in milk production or reproductive efficiency.

  17. Time manages interference in visual short-term memory.

    Science.gov (United States)

    Smith, Amy V; McKeown, Denis; Bunce, David

    2017-09-01

    Emerging evidence suggests that age-related declines in memory may reflect a failure in pattern separation, a process that is believed to reduce the encoding overlap between similar stimulus representations during memory encoding. Indeed, behavioural pattern separation may be indexed by a visual continuous recognition task in which items are presented in sequence and observers report for each whether it is novel, previously viewed (old), or whether it shares features with a previously viewed item (similar). In comparison to young adults, older adults show a decreased pattern separation when the number of items between "old" and "similar" items is increased. Yet the mechanisms of forgetting underpinning this type of recognition task are yet to be explored in a cognitively homogenous group, with careful control over the parameters of the task, including elapsing time (a critical variable in models of forgetting). By extending the inter-item intervals, number of intervening items and overall decay interval, we observed in a young adult sample (N = 35, M age  = 19.56 years) that the critical factor governing performance was inter-item interval. We argue that tasks using behavioural continuous recognition to index pattern separation in immediate memory will benefit from generous inter-item spacing, offering protection from inter-item interference.

  18. Regulatory design for RES-E support mechanisms: Learning curves, market structure, and burden-sharing

    International Nuclear Information System (INIS)

    Batlle, C.; Pérez-Arriaga, I.J.; Zambrano-Barragán, P.

    2012-01-01

    Drawing from relevant experiences in power systems around the world, this paper offers a review of existing policy support mechanisms for RES-E, with a detailed analysis of their regulatory implications. While recent studies provide an account of current RES-E support systems, in this paper we focus on some of the impacts these mechanisms have on the overall energy market structure and its performance. Given the rising importance of RES-E in systems everywhere, these impacts should no longer be overlooked. - Highlights: ► This paper offers a critical review of RES-E support mechanisms and their regulatory implications. ► The discussion focuses on how the different schemes impact the performance of the energy markets. ► We propose to redesign of current RES-E mechanisms to optimize incentives and market performance. ► Our recommendation is also to gradually move from price-based mechanisms to auctions.

  19. An Excitatory Neural Assembly Encodes Short-Term Memory in the Prefrontal Cortex

    Directory of Open Access Journals (Sweden)

    Yonglu Tian

    2018-02-01

    Full Text Available Short-term memory (STM is crucial for animals to hold information for a small period of time. Persistent or recurrent neural activity, together with neural oscillations, is known to encode the STM at the cellular level. However, the coding mechanisms at the microcircuitry level remain a mystery. Here, we performed two-photon imaging on behaving mice to monitor the activity of neuronal microcircuitry. We discovered a neuronal subpopulation in the medial prefrontal cortex (mPFC that exhibited emergent properties in a context-dependent manner underlying a STM-like behavior paradigm. These neuronal subpopulations exclusively comprise excitatory neurons and mainly represent a group of neurons with stronger functional connections. Microcircuitry plasticity was maintained for minutes and was absent in an animal model of Alzheimer’s disease (AD. Thus, these results point to a functional coding mechanism that relies on the emergent behavior of a functionally defined neuronal assembly to encode STM.

  20. Lack of color integration in visual short-term memory binding.

    Science.gov (United States)

    Parra, Mario A; Cubelli, Roberto; Della Sala, Sergio

    2011-10-01

    Bicolored objects are retained in visual short-term memory (VSTM) less efficiently than unicolored objects. This is unlike shape-color combinations, whose retention in VSTM does not differ from that observed for shapes only. It is debated whether this is due to a lack of color integration and whether this may reflect the function of separate memory mechanisms. Participants judged whether the colors of bicolored objects (each with an external and an internalcolor) were the same or different across two consecutive screens. Colors had to be remembered either individually or in combination. In Experiment 1, external colors in the combined colors condition were remembered better than the internal colors, and performance for both was worse than that in the individual colors condition. The lack of color integration observed in Experiment 1 was further supported by a reduced capacity of VSTM to retain color combinations, relative to individual colors (Experiment 2). An additional account was found in Experiment 3, which showed spared color-color binding in the presence of impaired shape-color binding in a brain-damaged patient, thus suggesting that these two memory mechanisms are different.