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Sample records for activation patterns underlying

  1. Spatial variability of microbial activity and substrate utilization patterns in top- and subsoils under European beech

    Niebuhr, Jana; Heinze, Stefanie; Mikutta, Robert; Mueller, Carsten W.; Preusser, Sebastian; Marschner, Bernd

    2014-05-01

    The role of subsoils in the global carbon cycle is poorly understood and probably underestimated. This is due to an incomplete understanding of processes and mechanisms that influence carbon storage and decomposition in deeper soil horizons. Microbial communities play an important role in these processes, as their presence, structure and function are crucial for the decomposition and/or stabilization of organic compounds. In this study, carried out in a European beech (Fagus sylvatica L.) forest on a podzolic Cambisol near Hannover, the spatial variability of microbial activity and substrate utilization patterns were investigated in the subsoil. For this purpose, samples were taken from regular grids at dm distances in three soil profiles of 1.85 m depth and 3.15 m length, totaling 192 soil samples. Activities of 9 extracellular enzymes of the C-, S-, P- and N-cycle were determined with a multi-substrate enzymatic assay and for substrate utilization patterns the MicroRespTM method was applied. The results showed a strong decline of microbial activity from topsoil to subsoil. Enzyme activities varied greatly at the dm scale. The correlation of the variability of both microbial activity and substrate utilization patterns with depth and soil parameters such as pH, soil water content, total and dissolved organic carbon was tested with a principal component analysis. Existing dependencies of the variabilities on these parameters help to verify the hypotheses that microbial activity is spatially highly variable in the subsoil and this variability is due to the existence of certain hot spots of substrate availability and that outside these 'hot spots' the microbial activity and thus the decomposition of SOM are mainly limited by substrate availability.

  2. Activity pattern and thermal biology of a day-flying hawkmoth (Macroglossum stellatarum) under Mediterranean summer conditions

    Herrera, Carlos M.

    1992-01-01

    1 The daily activity pattern and aspects of the thermal biology are described for the day-flying hawkmoth, Macroglossum stellatarum L. (Lepidoptera: Sphingidae), while foraging at a flowering population of Lavandula latifolia (Labiatae) under the dry-hot summer conditions of a southeastern Spanish locality. 2 The average abundance of M.stellatarum remained fairly constant from sunrise to about 17.00 hours (GMT), and a distinct peak occurred in the evening (18.00—20.00 hou...

  3. Activity Patterns of Wild Rabbit (Oryctolagus cuniculus, L.1758, under Semi-Freedom Conditions, during Autumn and Winter

    Díez, C.

    2005-06-01

    Full Text Available The main objective of this work is to assess the activity biorhythms of the European rabbit, under semi-freedom conditions between September and March. The study was carried out in a property located in the north of the County of Valladolid (Spain. Nine wild adult animals, 2 males and 7 females, were used. They were marked individually with a microchip (AVID(r. These animals were lodged in a 0.5 ha. enclosure. It was composed of two areas, one smaller where burrows were located and a bigger area, in which animals had fresh food and water. Both areas were separated by a metallic net provided of two passageways, in which, two microchips readers were placed to register animal activity. Each register indicated date, hour and code of the animal that had gone through the passageway. An activity rate was determined as the number of times that the total of the animals went through all the passageways, per hour of each day of the study. A monthly index of activity was also determined by the average of the daily activity rates during each month. It was observed that wild rabbits present a pronounced twilight and night-time activity, with two activity peaks which coincide with the sunrise and sunset. It was also determined that the activity of the animals in central hours of the day was practically null in both sexes. The activity pattern was changing, gradually, in function of the hour of sunrise and sunset on each month of the study. The activity index increased from September on, reaching a maximum peak during December, and decreased gradually until February when this index increased slightly until the finalization of the study on March. This pattern can be associated with the reproductive rhythms of the wild rabbit in the study area, during this period.

  4. Pattern Matching under Polynomial Transformation

    Butman, Ayelet; Clifford, Raphael; Jalsenius, Markus; Lewenstein, Noa; Porat, Benny; Porat, Ely; Sach, Benjamin

    2011-01-01

    We consider a class of pattern matching problems where a polynomial transformation can be applied to the pattern at every alignment. Given a pattern of length m and a longer text of length n where both are assumed to contain integer values only, we show O(n log m) algorithms for pattern matching under linear transformations even when wildcard symbols can occur in the input. We then show how to extend the technique to polynomial transformations of arbitrary degree. Next we consider the problem of finding the minimum Hamming distance under polynomial transformation. We show that, for any epsilon > 0, there cannot exist an O(nm^(1-epsilon)) algorithm for additive and linear transformations conditional on the hardness of the classic 3SUM problem. Finally, we consider a version of the Hamming distance problem under additive transformations with a bound k on the maximum distance that need be reported. We give a deterministic O(nk log k) time solution which we then improve by careful use of randomisation to O(n sqrt...

  5. Innovation patterns under the magnifying glass: Firm-level latent class analysis of innovation activities in services

    Trigo, Alexandre

    2009-01-01

    Innovation is still an obscure concept although many efforts have been made to improve the understanding and measurement of it. The growth of service activities throughout the economy has encouraged scholars, policy makers and executives to explore the determinants and features of the innovation developed by service enterprises. Many empirical studies that form the basis of recent literature on innovation in services have proved the existence of a wide range of innovation patterns, confuting ...

  6. Time history speckle pattern under statistical view

    Braga, R. A.; Silva, W. S.; Sáfadi, T.; Nobre, C. M. B.

    2008-05-01

    The dynamic speckle analysis has been done because speckle interference began to be evaluated as an important source of information, especially those related to biological samples under laser beam. The time history speckle pattern, a THSP image, is an approach to analyze, which allows a summary to represent the activity monitored. THSP adoption has compelled the research to evaluate the information and the reliability of its inner pattern. This study presents a statistical approach to analyze the data using white noise tests and cross-spectrum analysis. The data analyzed was a set of THSP from animal sperm samples. The evaluation of white noise among lines was conducted using the Fischer test over eight THSP and the cross-spectral approach has been conducted by comparing the information in each THSP. The results presented that the THSP of the sperm did not behave as a white noise in a global evaluation, and specifically in the Gaussian white noise test over 4096 lines; only six lines presented the behavior of a white noise pattern. The strong rejection of white noise test confirms that the THSP pattern allows reliable information. The results obtained with the cross-spectral analysis presented differences between lines within the same THSP, showing that the information of an inner pattern varies in relation to space, which is against the findings in literature.

  7. Interplanting Patterns of Cash Crops under Forest

    Renjie; DU; Yuejun; QU; Hu; JIN; Haibo; JIANG; Yunchang; DU; Dongyue; ZHOU; Jing; FU; Ping; SHI

    2014-01-01

    At the same time of tending forests,it is necessary to explore the under-forest economic development mode,bring into play production function of economic plants,establish cultivation mode of edible fungus,wild vegetables and medicinal plants under forest,to obtain certain economic benefit in short period. This paper made a preliminary study on significance and existing problems of the under-forest economy,and came up with several interplanting patterns,in the hope of providing a comprehensive operation and cultivation approach for developing the under-forest economy.

  8. Chimera patterns under the impact of noise

    Loos, Sarah A. M.; Claussen, Jens Christian; Schöll, Eckehard; Zakharova, Anna

    2015-01-01

    We investigate two types of chimera states, i.e., patterns consisting of coexisting spatially separated domains with coherent and incoherent dynamics, in ring networks of Stuart-Landau oscillators with symmetry-breaking coupling, under the influence of noise. Amplitude chimeras are characterized by temporally periodic dynamics throughout the whole network, but spatially incoherent behavior with respect to the amplitudes in a part of the system; they are long-living transients. Chimera death s...

  9. Chimera patterns under the impact of noise

    Loos, Sarah A. M.; Claussen, Jens Christian; Schöll, Eckehard; Zakharova, Anna

    2016-01-01

    We investigate two types of chimera states, patterns consisting of coexisting spatially separated domains with coherent and incoherent dynamics, in ring networks of Stuart-Landau oscillators with symmetry-breaking coupling, under the influence of noise. Amplitude chimeras are characterized by temporally periodic dynamics throughout the whole network, but spatially incoherent behavior with respect to the amplitudes in a part of the system; they are long-living transients. Chimera death states generalize chimeras to stationary inhomogeneous patterns (oscillation death), which combine spatially coherent and incoherent domains. We analyze the impact of random perturbations, addressing the question of robustness of chimera states in the presence of white noise. We further consider the effect of symmetries applied to random initial conditions.

  10. Universal patterns underlying ongoing wars and terrorism

    Johnson, N F; Restrepo, J A; Becerra, O; Bohorquez, J C; Suárez, N; Restrepo, E M; Zarama, R; Johnson, Neil F.; Spagat, Mike; Restrepo, Jorge A.; Becerra, Oscar; Bohorquez, Juan Camilo; Suarez, Nicolas; Restrepo, Elvira Maria; Zarama, Roberto

    2006-01-01

    We report a remarkable universality in the patterns of violence arising in three high-profile ongoing wars, and in global terrorism. Our results suggest that these quite different conflict arenas currently feature a common type of enemy, i.e. the various insurgent forces are beginning to operate in a similar way regardless of their underlying ideologies, motivations and the terrain in which they operate. We provide a microscopic theory to explain our main observations. This theory treats the insurgent force as a generic, self-organizing system which is dynamically evolving through the continual coalescence and fragmentation of its constituent groups.

  11. Primary succession seen through the shifted patterns of plant traits and soil macrofauna above/under-ground activity, a different ecological perspective towards post mining sites

    Moradi, Jabbar; Mudrak, Ondrej; Frouz, Jan

    2016-04-01

    to "late succession species" of the oldest ages such as legumes.We infer that by time passing, thru soil development in older sites, soil medium became more favorable for larval stages and endogeic lifestyle of fauna, in other words, environmental selection and consequently the successful colonization of fauna holding the similar trait (i.e. epigeic activity) ended up in an endogeic community shift towards developed soils under older sites. The shift in CWM value of fauna community clearly shows importance of soil development for a stable colonization and regeneration of migrated communities. Traits related to life history of fauna, e.g. epigeic and endogeic, as well as correlated plant traits instead of plant species communities, i.e. LDMC and plant forms, can be of great value for an enhanced perception of the community pattern dynamics through time and space. The incorporation of trait diversity in primary and secondary successional studies seems to be promising in order to gain a better understanding of the successional changes.

  12. NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION

    Wang, Lumin [Regents of the University of Michigan; Lu, Wei [Regents of the University of Michigan

    2013-01-31

    understanding of fundamental scientific basis for the irradiation-induced self-organization processes. The fundamental physical mechanisms underlying ordered pattern formation, which include defect production and migration, ion sputtering, redeposition, viscous flow and diffusion, are investigated through a combination of modeling and in situ and ex-situ observations [3,9,11]. In addition, these nanostructured materials exhibit considerable improvement of optical properties [9,12,13]. For example, patterned Ge with a hexagonally ordered, honeycomb-like structure of nanoscale holes possesses a high surface area and a considerably blue-shifted energy gap [9], and oxidation of ordered Ga droplets shows noticeable enhancement of optical transmission [12]. This research has addressed nanopattern formation in a variety of materials under ion bombardment and provided a fundamental understanding of the dynamic mechanisms involved. In addition, have also stared to systematically investigate pattern formation under ion irradiation for more systems with varied experimental conditions and computation, including the collaboration with Dr. Veena Tikare of Sandia National Laboratory with a hybrid computation method at the ending this grant. A more detailed relationship between nanostructure formation and experimental conditions will be revealed with our continued efforts.

  13. Under-forest Breeding Pattern and the Practice Form

    Shen, Zhong-ming

    2012-01-01

    Through the development in recent years, China's under-forest breeding pattern can be divided into four kinds of practice form of under-forest breeding pattern (the pattern of breeding driven by leading enterprises; the pattern of breeding driven by intermediary economic organizations; the pattern of breeding driven by the professional wholesale market; the pattern of breeding driven by the modern animal husbandry demonstration areas), according to difference in the main body participating in...

  14. Sow-activity classification from acceleration patterns

    Escalante, Hugo Jair; Rodriguez, Sara V.; Cordero, Jorge; Kristensen, Anders Ringgaard; Cornou, Cecile

    2013-01-01

    sow-activity classification can be approached with standard machine learning methods for pattern classification. Individual predictions for elements of times series of arbitrary length are combined to classify it as a whole. An extensive comparison of representative learning algorithms, including......This paper describes a supervised learning approach to sow-activity classification from accelerometer measurements. In the proposed methodology, pairs of accelerometer measurements and activity types are considered as labeled instances of a usual supervised classification task. Under this scenario...... neural networks, support vector machines, and ensemble methods, is presented. Experimental results are reported using a data set for sow-activity classification collected in a real production herd. The data set, which has been widely used in related works, includes measurements from active (Feeding...

  15. Earthquake networks based on similar activity patterns.

    Tenenbaum, Joel N; Havlin, Shlomo; Stanley, H Eugene

    2012-10-01

    Earthquakes are a complex spatiotemporal phenomenon, the underlying mechanism for which is still not fully understood despite decades of research and analysis. We propose and develop a network approach to earthquake events. In this network, a node represents a spatial location while a link between two nodes represents similar activity patterns in the two different locations. The strength of a link is proportional to the strength of the cross correlation in activities of two nodes joined by the link. We apply our network approach to a Japanese earthquake catalog spanning the 14-year period 1985-1998. We find strong links representing large correlations between patterns in locations separated by more than 1000 kilometers, corroborating prior observations that earthquake interactions have no characteristic length scale. We find network characteristics not attributable to chance alone, including a large number of network links, high node assortativity, and strong stability over time. PMID:23214652

  16. Under-forest Breeding Pattern and the Practice Form

    SHEN Zhong-ming

    2012-01-01

    Through the development in recent years, China’s under-forest breeding pattern can be divided into four kinds of practice form of under-forest breeding pattern (the pattern of breeding driven by leading enterprises; the pattern of breeding driven by intermediary economic organizations; the pattern of breeding driven by the professional wholesale market; the pattern of breeding driven by the modern animal husbandry demonstration areas), according to difference in the main body participating in signing the operation contract in breeding pattern. In the production practice of under-forest breeding pattern, the most widely used and successful pattern is the pattern of breeding driven by leading enterprises and its derivative forms.

  17. Behaviour of a few mode fiber modal pattern under stress

    Egalon, Claudio O.; Rogowski, Robert S.

    1991-01-01

    A numerical model was developed to calculate the interference pattern at the end of a multimode weakly guiding optical fiber under stress. Whenever an optical fiber is under stress, the modal phase in the interference term of the intensity formula changes. Plots of the simulated output of a stressed fiber are presented. For multimode fibers, very complicated patterns result. Under stress, lobes in the pattern are generated, displaced and power is exchanged among them.

  18. Variable pattern contamination control under positive pressure

    Philippi, H.M. [Chalk River Labs., Ontario (Canada)

    1997-08-01

    Airborne contamination control in nuclear and biological laboratories is traditionally achieved by directing the space ventilation air at subatmospheric pressures in one fixed flow pattern. However, biological and nuclear contamination flow control in the new Biological Research Facility, to be commissioned at the Chalk River Laboratories in 1996, will have the flexibility to institute a number of contamination control patterns, all achieved at positive (above atmospheric) pressures. This flexibility feature, made possible by means of a digitally controlled ventilation system, changes the facility ventilation system from being a relatively rigid building service operated by plant personnel into a flexible building service which can be operated by the facility research personnel. This paper focuses on and describes the application of these unique contamination control features in the design of the new Biological Research Facility. 3 refs., 7 figs.

  19. Pattern Activation/Recognition Theory of Mind

    Bertrand edu Castel

    2015-07-01

    Full Text Available In his 2012 book How to Create a Mind, Ray Kurzweil defines a Pattern Recognition Theory of Mind that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call Pattern Activation/Recognition Theory of Mind. While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation.

  20. Pattern activation/recognition theory of mind.

    du Castel, Bertrand

    2015-01-01

    In his 2012 book How to Create a Mind, Ray Kurzweil defines a "Pattern Recognition Theory of Mind" that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call "Pattern Activation/Recognition Theory of Mind." While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation. PMID:26236228

  1. Default activity patterns at the neocortical microcircuit level

    Artur Luczak

    2012-06-01

    Full Text Available Even in absence of sensory stimuli cortical networks exhibit complex, self-organized activity patterns. While the function of those spontaneous patterns of activation remains poorly understood, recent studies both in vivo and in vitro have demonstrated that neocortical neurons activate in a surprisingly similar sequential order both spontaneously and following input into cortex. For example, neurons that tend to fire earlier within spontaneous bursts of activity also fire earlier than other neurons in response to sensory stimuli. These 'default patterns' can last hundreds of milliseconds and are strongly conserved under a variety of conditions. In this paper we will review recent evidence for these default patterns at the local cortical level. We speculate that cortical architecture imposes common constraints on spontaneous and evoked activity flow, which result in the similarity of the patterns.

  2. Pattern Formation on Networks: from Localised Activity to Turing Patterns

    McCullen, Nick; Wagenknecht, Thomas

    2016-06-01

    Networks of interactions between competing species are used to model many complex systems, such as in genetics, evolutionary biology or sociology and knowledge of the patterns of activity they can exhibit is important for understanding their behaviour. The emergence of patterns on complex networks with reaction-diffusion dynamics is studied here, where node dynamics interact via diffusion via the network edges. Through the application of a generalisation of dynamical systems analysis this work reveals a fundamental connection between small-scale modes of activity on networks and localised pattern formation seen throughout science, such as solitons, breathers and localised buckling. The connection between solutions with a single and small numbers of activated nodes and the fully developed system-scale patterns are investigated computationally using numerical continuation methods. These techniques are also used to help reveal a much larger portion of of the full number of solutions that exist in the system at different parameter values. The importance of network structure is also highlighted, with a key role being played by nodes with a certain so-called optimal degree, on which the interaction between the reaction kinetics and the network structure organise the behaviour of the system.

  3. Pattern Formation on Networks: from Localised Activity to Turing Patterns.

    McCullen, Nick; Wagenknecht, Thomas

    2016-01-01

    Networks of interactions between competing species are used to model many complex systems, such as in genetics, evolutionary biology or sociology and knowledge of the patterns of activity they can exhibit is important for understanding their behaviour. The emergence of patterns on complex networks with reaction-diffusion dynamics is studied here, where node dynamics interact via diffusion via the network edges. Through the application of a generalisation of dynamical systems analysis this work reveals a fundamental connection between small-scale modes of activity on networks and localised pattern formation seen throughout science, such as solitons, breathers and localised buckling. The connection between solutions with a single and small numbers of activated nodes and the fully developed system-scale patterns are investigated computationally using numerical continuation methods. These techniques are also used to help reveal a much larger portion of of the full number of solutions that exist in the system at different parameter values. The importance of network structure is also highlighted, with a key role being played by nodes with a certain so-called optimal degree, on which the interaction between the reaction kinetics and the network structure organise the behaviour of the system. PMID:27273339

  4. High Performance Hierarchical Torus Network Under Adverse Traffic Patterns

    MM Hafizur Rahman

    2012-03-01

    Full Text Available A Hierarchical Torus Network (HTN is a 2D-torus network of multiple basic modules, in which the basic modules are 3D-torus networks that are hierarchically interconnected for higher level networks. The dynamic communication performance of the HTN using the dimension-order routing under common traffic patterns have been evaluated, and have been shown to be good. However, dynamic communication performance of HTN under adverse traffic patterns has not been evaluated yet. In this paper, we evaluate the dynamic communication performance of HTN using a deadlock-free dimension order routing with 3 virtual channels under adverse traffic patterns, and compare it with H3D-mesh, mesh, and torus networks. It is shown that even under adverse traffic patterns, the HTN yields high throughput and low average transfer time, which provide better dynamic communication performance than H3D-mesh, mesh, and torus networks.

  5. Variable Patterned Pudendal Nerve Stimuli Improves Reflex Bladder Activation

    Bruns, Tim M.; Bhadra, Narendra; Gustafson, Kenneth J.

    2008-01-01

    We evaluated variable patterns of pudendal nerve (PN) stimuli for reflex bladder excitation. Reflex activation of the bladder has been demonstrated previously with 20–33 Hz continuous stimulation of PN afferents. Neuronal circuits accessed by afferent mediated pathways may respond better to physiological patterned stimuli than continuous stimulation. Unilateral PN nerve cuffs were placed in neurologically intact male cats. PN stimulation (0.5–100 Hz) was performed under isovolumetric conditio...

  6. Signal Processing under Active Monitoring

    Mostovyi, Oleksii

    2005-01-01

    This paper describes a method of signal preprocessing under active monitoring. Suppose we want to solve the inverse problem of getting the response of a medium to one powerful signal, which is equivalent to obtaining the transmission function of the medium, but do not have an opportunity to conduct such an experiment (it might be too expensive or harmful for the environment). Practically the problem can be reduced to obtaining the transmission function of the medium. In this case ...

  7. Relationships between hippocampal activity and breathing patterns

    Harper, R M; Poe, G R; Rector, D M; Kristensen, Morten Pilgaard

    1998-01-01

    Single cell discharge, EEG activity, and optical changes accompanying alterations in breathing patterns, as well as the knowledge that respiratory musculature is heavily involved in movement and other behavioral acts, implicate hippocampal regions in some aspects of breathing control. The control...

  8. Patterned activity within the local cortical architecture

    Farran Briggs

    2010-01-01

    The cerebral cortex is a vastly complex structure consisting of multiple distinct populations of neurons residing in functionally specialized cortical compartments. A fundamental goal in systems neuroscience is to understand the interactions among cortical neurons and their relationship to behavior. It is hypothesized that dynamic activity patterns, such as oscillations in global neuronal activity, could span large, heterogeneous populations of cortical neurons in such a manner as to bind t...

  9. Interfacial pattern selection in miscible liquids under vibration.

    Gaponenko, Y; Torregrosa, M M; Yasnou, V; Mialdun, A; Shevtsova, V

    2015-11-14

    We explore the peculiar behaviour of an interface between two miscible liquids of similar (but non-identical) viscosities and densities under horizontal vibration with a frequency less than 25 Hz. Significant differences in the structure of the formed patterns were found between microgravity and ground experiments. In a gravity field, a spatially periodic saw-tooth frozen structure is generated in the interface which dissipates at long times. By contrast, under the low gravity conditions of a parabolic flight, the long lived pattern consists of a series of vertical columns of alternating liquids. PMID:26365134

  10. Perceptual similarity of visual patterns predicts dynamic neural activation patterns measured with MEG.

    Wardle, Susan G; Kriegeskorte, Nikolaus; Grootswagers, Tijl; Khaligh-Razavi, Seyed-Mahdi; Carlson, Thomas A

    2016-05-15

    Perceptual similarity is a cognitive judgment that represents the end-stage of a complex cascade of hierarchical processing throughout visual cortex. Previous studies have shown a correspondence between the similarity of coarse-scale fMRI activation patterns and the perceived similarity of visual stimuli, suggesting that visual objects that appear similar also share similar underlying patterns of neural activation. Here we explore the temporal relationship between the human brain's time-varying representation of visual patterns and behavioral judgments of perceptual similarity. The visual stimuli were abstract patterns constructed from identical perceptual units (oriented Gabor patches) so that each pattern had a unique global form or perceptual 'Gestalt'. The visual stimuli were decodable from evoked neural activation patterns measured with magnetoencephalography (MEG), however, stimuli differed in the similarity of their neural representation as estimated by differences in decodability. Early after stimulus onset (from 50ms), a model based on retinotopic organization predicted the representational similarity of the visual stimuli. Following the peak correlation between the retinotopic model and neural data at 80ms, the neural representations quickly evolved so that retinotopy no longer provided a sufficient account of the brain's time-varying representation of the stimuli. Overall the strongest predictor of the brain's representation was a model based on human judgments of perceptual similarity, which reached the limits of the maximum correlation with the neural data defined by the 'noise ceiling'. Our results show that large-scale brain activation patterns contain a neural signature for the perceptual Gestalt of composite visual features, and demonstrate a strong correspondence between perception and complex patterns of brain activity. PMID:26899210

  11. Spontaneous Plasticity of Multineuronal Activity Patterns in Activated Hippocampal Networks

    Atsushi Usami

    2008-01-01

    Full Text Available Using functional multineuron imaging with single-cell resolution, we examined how hippocampal networks by themselves change the spatiotemporal patterns of spontaneous activity during the course of emitting spontaneous activity. When extracellular ionic concentrations were changed to those that mimicked in vivo conditions, spontaneous activity was increased in active cell number and activity frequency. When ionic compositions were restored to the control conditions, the activity level returned to baseline, but the weighted spatial dispersion of active cells, as assessed by entropy-based metrics, did not. Thus, the networks can modify themselves by altering the internal structure of their correlated activity, even though they as a whole maintained the same level of activity in space and time.

  12. Circulation patterns in active lava lakes

    Redmond, T. C.; Lev, E.

    2014-12-01

    Active lava lakes provide a unique window into magmatic conduit processes. We investigated circulation patterns of 4 active lava lakes: Kilauea's Halemaumau crater, Mount Erebus, Erta Ale and Nyiragongo, and in an artificial "lava lake" constructed at the Syracuse University Lava Lab. We employed visual and thermal video recordings collected at these volcanoes and use computer vision techniques to extract time-dependent, two-dimensional surface velocity maps. The large amount of data available from Halemaumau enabled us to identify several characteristic circulation patterns. One such pattern is a rapid acceleration followed by rapid deceleration, often to a level lower than the pre-acceleration level, and then a slow recovery. Another pattern is periodic asymmetric peaks of gradual acceleration and rapid deceleration, or vice versa, previously explained by gas pistoning. Using spectral analysis, we find that the dominant period of circulation cycles at approximately 30 minutes, 3 times longer than the dominant period identified previously for Mount Erebus. Measuring a complete surface velocity field allowed us to map and follow locations of divergence and convergence, therefore upwelling and downwelling, thus connecting the surface flow with that at depth. At Nyiragongo, the location of main upwelling shifts gradually, yet is usually at the interior of the lake, for Erebus it is usually along the perimeter yet often there is catastrophic downwelling at the interior; For Halemaumau upwelling/downwelling position is almost always on the perimeter. In addition to velocity fields, we developed an automated tool for counting crustal plates at the surface of the lava lakes, and found a correlation, and a lag time, between changes if circulation vigor and the average size of crustal plates. Circulation in the artificial basaltic lava "lake" was limited by its size and degree of foaming, yet we measured surface velocities and identify patterns. Maximum surface velocity

  13. General Neutrino Mass Matrix Patterns and Its Underlying Family Symmetries

    Damanik, Asan; Anggraita, Pramudita; Muslim,

    2014-01-01

    Baseon on current experimental results, such as neutrino oscillations and the neutrinoless double beta decays (i.e. data from Super Kamiokande, KamLAND, SNO, etc.), the neutrino mixing matrix can be adequately determined. Though there are still certain parameters that have possibility limits, but based on the current experimental results it is possible to construct a general form of neutrino mass matrix. Starting from this general form of the neutrino mass matrix we put certain conditions in the context of the seesaw mechanism model to determine the possible pattern of the neutrino mass matrix that has a texture zero. From the obtained neutrino mass matrix pattern, there are three class of patterns, where two of the class are known to be realized in literature by the underlying family symmetries of the $D_{4}$ and $A_{4}$ groups, the dihedral and tetrahedral symmetry groups.

  14. Root activity pattern of eucalyptus camaldulensis dehnhardt

    The root activity pattern of a seven-year-old E. camaldulensis was studied by 32P capsule placement technique. The study revealed that nearly two-third of the roots of E. camaldulensis are confined to the top 60 cm of the soil layer. Laterally, one-third of the roots are confined within the 50 cm radial distance from the trunk of the tree and the remaining two-thirds are spread at a radial distance of 75 to 100 cm. (author)

  15. New activity pattern in human interactive dynamics

    Formentin, Marco; Lovison, Alberto; Maritan, Amos; Zanzotto, Giovanni

    2015-09-01

    We investigate the response function of human agents as demonstrated by written correspondence, uncovering a new pattern for how the reactive dynamics of individuals is distributed across the set of each agent’s contacts. In long-term empirical data on email, we find that the set of response times considered separately for the messages to each different correspondent of a given writer, generate a family of heavy-tailed distributions, which have largely the same features for all agents, and whose characteristic times grow exponentially with the rank of each correspondent. We furthermore show that this new behavioral pattern emerges robustly by considering weighted moving averages of the priority-conditioned response-time probabilities generated by a basic prioritization model. Our findings clarify how the range of priorities in the inputs from one’s environment underpin and shape the dynamics of agents embedded in a net of reactive relations. These newly revealed activity patterns might be universal, being present in other general interactive environments, and constrain future models of communication and interaction networks, affecting their architecture and evolution.

  16. A study on the operator's communication pattern characteristics under abnormal operating situation of nuclear power plants

    The quality of a probabilistic safety assessment (PSA) has become more important and a human reliability analysis (HRA) is known as a major contributor to the uncertainty of a PSA. As a part of enhancing the HRA quality, a study was initiated to find out characteristics of communication pattern and to evaluate communication quality of the operators of nuclear power plants. Korea Atomic Energy Research Institute (KAERI) is developing evaluation methods for the effect of human-induced events on risk/performance. This paper describes a study on the operator's communication pattern characteristics under abnormal operating situation of nuclear power plants. The study was carried out in four stages; 1) Video recording 2) Audio scripting 3) Message Classification 4) Communication Pattern Analysis. We recorded eight abnormal simulator training programs from Younggwang nuclear power plant training center. After that we performed message classification and carried out communication pattern analysis. We compared communication patterns of abnormal operating situation with emergency operating situation.As results of analysis, the role of SRO (senior reactor operator) under abnormal operating situation was decreased than the activities under emergency operating situation because each operator (reactor operator, turbine operator, safety supervisor) in main control room (MCR) performs the activity to control by himself with corresponding field engineers with his basic knowledge of the system. On the other hand, the operator's decision making processes and activities under abnormal operating situation were dramatically increased than the emergency operating situation. (authors)

  17. Root activity patterns of some tree crops

    A coordinated research programme was followed using a soil injection method which employed 32P-labelled superphosphate solution. The technique was applied for determining the root activity distribution of various crops. Field experiments were carried out in Uganda on bananas, Spain and Taiwan on citrus, Ghana on cocoa, Columbia and Kenya on coffee, and Ivory Coast and Malaysia on oil palms, to study the patterns of root activity as a function of depth and distance from the tree base, soil type, tree age and season. A few weeks after injection, leaf samples of similar age were taken from well-defined morphological positions on the tree and analyzed for 32P. The activity of the label in the sample reflects the root activity at the various positions in the soil. Some preliminary experiments were also carried out using 32P-superphosphate to evaluate the efficiency of different methods of fertilizer placement in relation to phosphate uptake by the plantation as a whole

  18. Pattern of crescendo TWA may disclose the underlying cardiac pathology.

    Nieminen, Tuomo; Verrier, Richard L; Nikus, Kjell; Viik, Jari; Lehtinen, Rami; Lehtimäki, Terho; Kaiser, Willi; Kähönen, Mika

    2010-01-01

    We present an exercise test case in which crescendo TWA preceded ventricular tachycardia (VT). The patient was examined due to suspicion of ischemic heart disease. The ST-segment became elevated simultaneously with a distinct alternation in the ST-segment and the first half of the T-wave, and the patient developed polymorphic VT. Coronary angiography disclosed marked stenoses. Earlier reports of TWA in patients with congenital long QT syndrome show a pattern in which the T wave frequently alternates above and below the isoelectric line without concomitant ST-segment changes. In Brugada syndrome patients, the signature ST-T wave pattern is the locus of alternation. Future investigation should elucidate whether specific TWA morphologies may expose underlying heart disease. PMID:20413129

  19. Early patterns of commercial activity in graphene

    Graphene, a novel nanomaterial consisting of a single layer of carbon atoms, has attracted significant attention due to its distinctive properties, including great strength, electrical and thermal conductivity, lightness, and potential benefits for diverse applications. The commercialization of scientific discoveries such as graphene is inherently uncertain, with the lag time between the scientific development of a new technology and its adoption by corporate actors revealing the extent to which firms are able to absorb knowledge and engage in learning to implement applications based on the new technology. From this perspective, we test for the existence of three different corporate learning and activity patterns: (1) a linear process where patenting follows scientific discovery; (2) a double-boom phenomenon where corporate (patenting) activity is first concentrated in technological improvements and then followed by a period of technology productization; and (3) a concurrent model where scientific discovery in publications occurs in parallel with patenting. By analyzing corporate publication and patent activity across country and application lines, we find that, while graphene as a whole is experiencing concurrent scientific development and patenting growth, country- and application-specific trends offer some evidence of the linear and double-boom models.

  20. West African spatial patterns of economic activities

    Walther, Olivier; Howard, Allen; Retaillé, Denis

    2015-01-01

    traders, and where their differences lie. Finally, we show how a combined approach can make a significant contribution to the scholarly study of space in West Africa. We argue that continuing dialogue among fields can contribute to a reassessment of development policies.......Over the last 30 years, two different bodies of literature developed by both US historians and francophone geographers have moved toward similar conclusions regarding West African economic spatial patterns. Despite their different backgrounds, both the ‘spatial factor’ approach promoted by...... historians and the ‘mobile space’ approach developed by geographers view exchange centres as nodes of transnational trade networks and places in production territories, and perceive spatial dynamics as highly dependent on shifts of trade flows and production activities. The objective of this article is to...

  1. Psychosocial factors underlying physical activity

    Ji Cheng-Ye; Middlestadt Susan E; Zhang Juan

    2007-01-01

    Abstract Background Given the increasing importance of obesity in China, prevention interventions encouraging physical activity by middle school students are needed. The purpose of this study is to illustrate how a rapid elicitation method can be used to identify salient consequences, referents, and circumstances about physical activity as perceived by middle school students and to provide suggestions for interventions and quantitative research. Method A theory-based qualitative study using a...

  2. Psychosocial factors underlying physical activity

    Ji Cheng-Ye

    2007-09-01

    Full Text Available Abstract Background Given the increasing importance of obesity in China, prevention interventions encouraging physical activity by middle school students are needed. The purpose of this study is to illustrate how a rapid elicitation method can be used to identify salient consequences, referents, and circumstances about physical activity as perceived by middle school students and to provide suggestions for interventions and quantitative research. Method A theory-based qualitative study using a self-completion elicitation was conducted with 155 students from two middle schools in Beijing, China. Following the Theory of Planned Behavior, six open-ended questions asked students for their perceptions about performing physical activity at least 60 minutes each day: advantages of participating in physical activity; disadvantages of doing so; people who approve of participation; people who disapprove; things that make it easy; and things that make it hard. Content analysis revealed categories of salient consequences, reference groups, and circumstances. Results While the three most frequently mentioned advantages elicited from the students were physical health consequences (e.g., will strengthen my body (58.7%, four of the salient advantages were not (e.g., will improve my grades (12.2%. Parents were the most frequently mentioned social referent (42.6% as approving; 27.7% as disapproving when students were asked who might approve or disapprove of their participation. Circumstances perceived to hinder daily physical activity included having too many assignments and not having enough time. Conclusion While many of the beliefs about physical activity elicited from this study were similar to those found with students from England and the US, several were unique to these students from Beijing. The results of this qualitative research suggest that interventions to encourage physical activity among middle school students should address: perceived consequences

  3. Categorizing Pedagogical Patterns by Teaching Activities and Pedagogical Values

    Bennedsen, Jens; Eriksen, Ole

    2006-01-01

    The main contribution of this paper is a proposal for a universal pedagogical pattern categorization based on teaching values and activities. This categorization would be more sustainable than the arbitrary categorization implied by pedagogical pattern language themes. Pedagogical patterns from two central patterns languages are analyzed and…

  4. Pattern formation in crystal growth under parabolic shear flow.

    Ueno, K

    2003-08-01

    Morphological instability of the solid-liquid interface occurring in a crystal growing from an undercooled thin liquid bounded on one side by a free surface and flowing down inclined plane, is investigated by a linear stability analysis under shear flow. It is found that restoring forces due to gravity and surface tension is an important factor for stabilization of the solid-liquid interface on long length scales. This is a stabilizing effect different from the Gibbs-Thomson effect. A particular long wavelength mode of about 1 cm of wavy pattern, observed on the surface of icicles covered with a thin layer of flowing water is obtained from the dispersion relation, including the effect of flow and restoring forces. PMID:14524982

  5. Passenger transport and household activity patterns

    Jørgensen, Kaj

    1997-01-01

    Review of Danish passenger transport patterns and analysis of energy consumption, emissions and safety impacts for selected typical households' travelling......Review of Danish passenger transport patterns and analysis of energy consumption, emissions and safety impacts for selected typical households' travelling...

  6. Air pollution exposure: An activity pattern approach for active transportation

    Adams, Matthew D.; Yiannakoulias, Nikolaos; Kanaroglou, Pavlos S.

    2016-09-01

    In this paper, we demonstrate the calculation of personal air pollution exposure during trips made by active transportation using activity patterns without personal monitors. We calculate exposure as the inhaled dose of particulate matter 2.5 μg or smaller. Two modes of active transportation are compared, and they include cycling and walking. Ambient conditions are calculated by combining mobile and stationary monitoring data in an artificial neural network space-time model. The model uses a land use regression framework and has a prediction accuracy of R2 = 0.78. Exposure is calculated at 10 m or shorter intervals during the trips using inhalation rates associated with both modes. The trips are children's routes between home and school. The average dose during morning cycling trips was 2.17 μg, during morning walking trips was 3.19 μg, during afternoon cycling trips was 2.19 μg and during afternoon walking trips was 3.23 μg. The cycling trip dose was significantly lower than the walking trip dose. The air pollution exposure during walking or cycling trips could not be strongly predicted by either the school or household ambient conditions, either individually or in combination. Multiple linear regression models regressing both the household and school ambient conditions against the dose were only able to account for, at most, six percent of the variance in the exposure. This paper demonstrates that incorporating activity patterns when calculating exposure can improve the estimate of exposure compared to its calculation from ambient conditions.

  7. Spatial patterns of European droughts under a moderate emission scenario

    Spinoni, J.; Naumann, G.; Vogt, J.

    2015-07-01

    Meteorological drought is generally defined as a prolonged deficiency of precipitation and is considered one of the most relevant natural hazards as the related impacts can involve many different sectors. In this study, we investigated the spatial patterns of European droughts for the periods 1981-2010, 2041-2070, and 2071-2100, focusing on the projections under a moderate emissions scenario. To do that, we used the outputs of the KNMI-RACMO2 model, which belongs to the A1B family and whose spatial resolution is 0.25° × 0.25°. By means of monthly precipitation and potential evapotranspiration (PET), we computed the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) at the 12-month accumulation scale. Thereafter, we separately obtained drought frequency, duration, severity, and intensity for the whole of Europe, excluding Iceland. According to both indicators, the spatial drought patterns are projected to follow what recently characterized Europe: southern Europe, who experienced many severe drought events in the last decades, is likely to be involved by longer, more frequent, severe, and intense droughts in the near future (2041-2070) and even more in the far future (2071-2100). This tendency is more evident using the SPEI, which also depends on temperature and consequently reflects the expected warming that will be highest for the Mediterranean area in Europe. On the other side, less severe and fewer drought events are likely to occur in northern Europe. This tendency is more evident using the SPI, because the precipitation increase is projected to outbalance the temperature (and PET) rise in particular in Scandinavia. Regarding the mid-latitudes, the SPEI-based analyses point at more frequent drought events, while the SPI-based ones point at less frequent events in these regions.

  8. Categorizing Pedagogical Patterns by Teaching Activities and Pedagogical Value

    Eriksen, Ole

    2006-01-01

    The main contribution of this paper is a proposal for a universal pedagogical pattern categorization based on teaching values and activities. This categorization would be more sustainable than the arbitrary categorization implied by pedagogical pattern language themes. Pedagogical patterns from two......-based categorization, we have combined it with a categorization based on teaching activities. The catalogue could be seen as a tool for combining pedagogical theories and patterns and it is a proposal for a solution to the problem of organizing pedagogical patterns....

  9. Pattern formation in directional solidification under shear flow. I. Linear stability analysis and basic patterns

    An asymptotic interface equation for directional solidification near the absolute stabiliy limit is extended by a nonlocal term describing a shear flow parallel to the interface. In the long-wave limit considered, the flow acts destabilizing on a planar interface. Moreover, linear stability analysis suggests that the morphology diagram is modified by the flow near onset of the Mullins-Sekerka instability. Via numerical analysis, the bifurcation structure of the system is shown to change. Besides the known hexagonal cells, structures consisting of stripes arise. Due to its symmetry-breaking properties, the flow term induces a lateral drift of the whole pattern, once the instability has become active. The drift velocity is measured numerically and described analytically in the framework of a linear analysis. At large flow strength, the linear description breaks down, which is accompanied by a transition to flow-dominated morphologies which is described in the following paper. Small and intermediate flows lead to increased order in the lattice structure of the pattern, facilitating the elimination of defects. Locally oscillating structures appear closer to the instability threshold with flow than without

  10. Active ultrasound pattern injection system (AUSPIS for interventional tool guidance.

    Xiaoyu Guo

    Full Text Available Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking.

  11. Pattern recognition to monitor Strombolian activity

    Cariolo, S.; Consorzio Cometa; La Via, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Mangiagli, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Reitano, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia

    2008-01-01

    The INGV (Catania Branch) camera network permits to monitor crater activity on Stromboli volcano. The goal of this work is monitoring strombolian activity in order to automatically classify different types of explosions and achieve real time identification of critical ones.

  12. Modeling of metal nanocluster growth on patterned substrates and surface pattern formation under ion bombardment

    Numazawa, Satoshi

    2012-11-01

    This work addresses the metal nanocluster growth process on prepatterned substrates, the development of atomistic simulation method with respect to an acceleration of the atomistic transition states, and the continuum model of the ion-beam inducing semiconductor surface pattern formation mechanism. Experimentally, highly ordered Ag nanocluster structures have been grown on pre-patterned amorphous SiO{sub 2} surfaces by oblique angle physical vapor deposition at room temperature. Despite the small undulation of the rippled surface, the stripe-like Ag nanoclusters are very pronounced, reproducible and well-separated. The first topic is the investigation of this growth process with a continuum theoretical approach to the surface gas condensation as well as an atomistic cluster growth model. The atomistic simulation model is a lattice-based kinetic Monte-Carlo (KMC) method using a combination of a simplified inter-atomic potential and experimental transition barriers taken from the literature. An effective transition event classification method is introduced which allows a boost factor of several thousand compared to a traditional KMC approach, thus allowing experimental time scales to be modeled. The simulation predicts a low sticking probability for the arriving atoms, millisecond order lifetimes for single Ag monomers and {approx}1 nm square surface migration ranges of Ag monomers. The simulations give excellent reproduction of the experimentally observed nanocluster growth patterns. The second topic specifies the acceleration scheme utilized in the metallic cluster growth model. Concerning the atomistic movements, a classical harmonic transition state theory is considered and applied in discrete lattice cells with hierarchical transition levels. The model results in an effective reduction of KMC simulation steps by utilizing a classification scheme of transition levels for thermally activated atomistic diffusion processes. Thermally activated atomistic movements

  13. Reverse inference of memory retrieval processes underlying metacognitive monitoring of learning using multivariate pattern analysis.

    Stiers, Peter; Falbo, Luciana; Goulas, Alexandros; van Gog, Tamara; de Bruin, Anique

    2016-05-15

    Monitoring of learning is only accurate at some time after learning. It is thought that immediate monitoring is based on working memory, whereas later monitoring requires re-activation of stored items, yielding accurate judgements. Such interpretations are difficult to test because they require reverse inference, which presupposes specificity of brain activity for the hidden cognitive processes. We investigated whether multivariate pattern classification can provide this specificity. We used a word recall task to create single trial examples of immediate and long term retrieval and trained a learning algorithm to discriminate them. Next, participants performed a similar task involving monitoring instead of recall. The recall-trained classifier recognized the retrieval patterns underlying immediate and long term monitoring and classified delayed monitoring examples as long-term retrieval. This result demonstrates the feasibility of decoding cognitive processes, instead of their content. PMID:26883066

  14. Synthetic reverberating activity patterns embedded in networks of cortical neurons

    Vardi, R.; Wallach, A.; Kopelowitz, E.; Abeles, M.; Marom, S.; Kanter, I.

    2012-03-01

    Synthetic reverberating activity patterns are experimentally generated by stimulation of a subset of neurons embedded in a spontaneously active network of cortical cells in vitro. The neurons are artificially connected by means of a conditional stimulation matrix, forming a synthetic local circuit with a predefined programmable connectivity and time delays. Possible uses of this experimental design are demonstrated, analyzing the sensitivity of these deterministic activity patterns to transmission delays and to the nature of ongoing network dynamics.

  15. Muscle activity pattern dependent pain development and alleviation

    Sjøgaard, Gisela; Søgaard, Karen

    2014-01-01

    Muscle activity is for decades considered to provide health benefits irrespectively of the muscle activity pattern performed and whether it is during e.g. sports, transportation, or occupational work tasks. Accordingly, the international recommendations for public health-promoting physical activity...... during physical activities at leisure and sport the motor recruitment patterns are more dynamic including regularly relatively high muscle forces - also activating type 2 muscles fibers - as well as periods of full relaxation even of the type 1 muscle fibers. Such activity is unrelated to muscle pain...

  16. Turing patterns and solitary structures under global control

    Pismen, L. M.

    1996-01-01

    Striped Turing patterns and solitary band and disk structures are constructed using a three-variable multiscale model with cubic nonlinearity and global control. The existence and stability conditions of regular structures are analysed using the equation of motion of curved boundaries between alternative states of the short-range component. The combined picture of transitions between striped and spotted patterns with changing level of global control is in qualitative agreement with the result...

  17. Preparation of activated carbon by chemical activation under vacuum.

    Juan, Yang; Ke-Qiang, Qiu

    2009-05-01

    Activated carbons especially used for gaseous adsorption were prepared from Chinesefir sawdust by zinc chloride activation under vacuum condition. The micropore structure, adsorption properties, and surface morphology of activated carbons obtained under atmosphere and vacuum were investigated. The prepared activated carbons were characterized by SEM, FTIR, and nitrogen adsorption. It was found that the structure of the starting material is kept after activation. The activated carbon prepared under vacuum exhibited higher values of the BET surface area (up to 1079 m2 g(-1)) and total pore volume (up to 0.5665 cm3 g(-1)) than those of the activated carbon obtained under atmosphere. This was attributed to the effect of vacuum condition that reduces oxygen in the system and limits the secondary reaction of the organic vapor. The prepared activated carbon has well-developed microstructure and high microporosity. According to the data obtained, Chinese fir sawdust is a suitable precursor for activated carbon preparation. The obtained activated carbon could be used as a low-cost adsorbent with favorable surface properties. Compared with the traditional chemical activation, vacuum condition demands less energy consumption, simultaneity, and biomass-oil is collected in the procedure more conveniently. FTIR analysis showed that heat treatment would result in the aromatization of the carbon structure. PMID:19534162

  18. Transcriptome analysis reveals novel patterning and pigmentation genes underlying Heliconius butterfly wing pattern variation

    Hines Heather M

    2012-06-01

    Full Text Available Abstract Background Heliconius butterfly wing pattern diversity offers a unique opportunity to investigate how natural genetic variation can drive the evolution of complex adaptive phenotypes. Positional cloning and candidate gene studies have identified a handful of regulatory and pigmentation genes implicated in Heliconius wing pattern variation, but little is known about the greater developmental networks within which these genes interact to pattern a wing. Here we took a large-scale transcriptomic approach to identify the network of genes involved in Heliconius wing pattern development and variation. This included applying over 140 transcriptome microarrays to assay gene expression in dissected wing pattern elements across a range of developmental stages and wing pattern morphs of Heliconius erato. Results We identified a number of putative early prepattern genes with color-pattern related expression domains. We also identified 51 genes differentially expressed in association with natural color pattern variation. Of these, the previously identified color pattern “switch gene” optix was recovered as the first transcript to show color-specific differential expression. Most differentially expressed genes were transcribed late in pupal development and have roles in cuticle formation or pigment synthesis. These include previously undescribed transporter genes associated with ommochrome pigmentation. Furthermore, we observed upregulation of melanin-repressing genes such as ebony and Dat1 in non-melanic patterns. Conclusions This study identifies many new genes implicated in butterfly wing pattern development and provides a glimpse into the number and types of genes affected by variation in genes that drive color pattern evolution.

  19. Classifying sows' activity types from acceleration patterns

    Cornou, Cecile; Lundbye-Christensen, Søren

    three-dimensional axes, plus the length of the acceleration vector) are selected for each activity. Each time series is modeled using a Dynamic Linear Model with cyclic components. The classification method, based on a Multi-Process Kalman Filter (MPKF), is applied to a total of 15 times series of 120...

  20. Spectral pattern recognition in under-sampled functions

    Shurtz, R.F.

    1988-08-01

    Fourier optics and an optical bench model are used to construct an ensemble of candidate functions representing variational patterns in an undersampled two dimensional function g(x,y). The known sample function s(x,y) is the product of g(x,y) and a set of unit impulses on the sample point pattern p(x,y) which, from the optical point of view, is an aperture imposing strict mathematical limits on what the sample can tell g(x,y). The laws of optics enforce much needed - and often lacking - conceptual discipline in reconstructing candidate variational patterns in g(x,y). The Fourier transform (FT) of s(x,y) is the convolution of the FT's of g(x,y) and p(x,y). If the convolution shows aliasing or confounding of frequencies undersampling is surely present and all reconstructions are indeterminate. Then information from outside s(x,y) is required and it is easily expressed in frequency terms so that the principles of optical filtering and image reconstruction can be applied. In the application described and pictured the FT of s(x,y) was filtered to eliminate unlikely or uninteresting high frequency amplitude maxima. A menu of the 100 strongest remaining terms was taken as indicating the principle variations patterns in g(x,y). Subsets of 10 terms from the menu were chosen using stepwise regression. By so restricting the subset size both the variance and the span of their inverse transforms were made consistent with those of the data. The amplitudes of the patterns being overdetermined, it was possible to estimate the phases also. The inverse transforms of 9 patterns so selected are regarded as ensembles of reconstructions, that is as stochastic process models, from which estimates of the mean and other moments can be calculated.

  1. Leisure Activity Patterns and Marital Conflict in Iran

    Ahmadi, Khodabakhsh; SAADAT, Hassan; Noushad, Siena

    2016-01-01

    Background: Over the past few decades, the association between leisure activity patterns and marital conflict or satisfaction has been studied extensively. However, most studies to date have been limited to middle-class families of developed societies, and an investigation of the issue, from a developing country perspective like Iran, is non-existent. Objectives: In an observational, analytical, cross-sectional study we aimed to investigate the relationship between leisure activity patterns a...

  2. Physical activity patterns in Greenland: A country in transition

    Dahl-Petersen, Inger; Jørgensen, Marit E; Bjerregaard, Peter

    2011-01-01

    To examine differences in physical activity patterns among Inuit in Greenland in relation to social transition. The Inuit in Greenland are an indigenous population in the circumpolar north who are experiencing rapid social transition.......To examine differences in physical activity patterns among Inuit in Greenland in relation to social transition. The Inuit in Greenland are an indigenous population in the circumpolar north who are experiencing rapid social transition....

  3. The pattern of genetic hitchhiking under recurrent mutation

    Hermisson, Joachim; Pfaffelhuber, Peter

    2008-01-01

    Genetic hitchhiking describes evolution at a neutral locus that is linked to a selected locus. If a beneficial allele rises to fixation at the selected locus, a characteristic polymorphism pattern (so-called selective sweep) emerges at the neutral locus. The classical model assumes that fixation of the beneficial allele occurs from a single copy of this allele that arises by mutation. However, recent theory (Pennings and Hermisson, 2006a; Pennings and Hermisson, 2006b) has shown that recurren...

  4. Distributed dynamical computation in neural circuits with propagating coherent activity patterns.

    Pulin Gong

    2009-12-01

    Full Text Available Activity in neural circuits is spatiotemporally organized. Its spatial organization consists of multiple, localized coherent patterns, or patchy clusters. These patterns propagate across the circuits over time. This type of collective behavior has ubiquitously been observed, both in spontaneous activity and evoked responses; its function, however, has remained unclear. We construct a spatially extended, spiking neural circuit that generates emergent spatiotemporal activity patterns, thereby capturing some of the complexities of the patterns observed empirically. We elucidate what kind of fundamental function these patterns can serve by showing how they process information. As self-sustained objects, localized coherent patterns can signal information by propagating across the neural circuit. Computational operations occur when these emergent patterns interact, or collide with each other. The ongoing behaviors of these patterns naturally embody both distributed, parallel computation and cascaded logical operations. Such distributed computations enable the system to work in an inherently flexible and efficient way. Our work leads us to propose that propagating coherent activity patterns are the underlying primitives with which neural circuits carry out distributed dynamical computation.

  5. Oral Electromyography Activation Patterns for Speech Are Similar in

    Walsh, Bridget; Smith, Anne

    2013-01-01

    Purpose: In this study, the authors determined whether basic patterns of muscle activation for speech were similar in preschool children who stutter and in their fluent peers. Method: Right and left lower lip muscle activity were recorded during conversational speech and sentence repetition in 64 preschool children diagnosed as stuttering (CWS)…

  6. Physical Activity Patterns of Youth with Down Syndrome

    Esposito, Phil E.; MacDonald, Megan; Hornyak, Joseph E.; Ulrich, Dale A.

    2012-01-01

    The purpose of this study was to examine the physical activity patterns of children with Down syndrome. A cross-sectional approach and accelerometry were used to measure the time children with Down syndrome (N = 104) spent in sedentary, light, and moderate-to-vigorous physical activity. Results indicated that adolescents from ages 14 to 15 years…

  7. Synaptic reverberation underlying mnemonic persistent activity.

    Wang, X J

    2001-08-01

    Stimulus-specific persistent neural activity is the neural process underlying active (working) memory. Since its discovery 30 years ago, mnemonic activity has been hypothesized to be sustained by synaptic reverberation in a recurrent circuit. Recently, experimental and modeling work has begun to test the reverberation hypothesis at the cellular level. Moreover, theory has been developed to describe memory storage of an analog stimulus (such as spatial location or eye position), in terms of continuous 'bump attractors' and 'line attractors'. This review summarizes new studies, and discusses insights and predictions from biophysically based models. The stability of a working memory network is recognized as a serious problem; stability can be achieved if reverberation is largely mediated by NMDA receptors at recurrent synapses. PMID:11476885

  8. Long term health implications of fitness and physical activity patterns.

    Riddoch, C; Savage, J M; N. Murphy; Cran, G W; Boreham, C

    1991-01-01

    Northern Ireland has the highest incidence of coronary heart disease (CHD) in the world. The physical fitness, activity patterns, health knowledge, attitudes, and dietary habits of a random, stratified sample of 3211 Northern Irish children, comprising 1540 boys and 1671 girls, age range 11-18 years were examined. At all ages boys were significantly more active than girls. The most important finding was an appreciable decline in physical activity levels after the age of 14 years reaching extr...

  9. Motor training increases the stability of activation patterns in the primary motor cortex.

    Yi Huang

    Full Text Available Learning to be skillful is an endowed talent of humans, but neural mechanisms underlying behavioral improvement remain largely unknown. Some studies have reported that the mean magnitude of neural activation is increased after learning, whereas others have instead shown decreased activation. In this study, we used functional magnetic resonance imaging (fMRI to investigate learning-induced changes in the neural activation in the human brain with a classic motor training task. Specifically, instead of comparing the mean magnitudes of activation before and after training, we analyzed the learning-induced changes in multi-voxel spatial patterns of neural activation. We observed that the stability of the activation patterns, or the similarity of the activation patterns between the even and odd runs of the fMRI scans, was significantly increased in the primary motor cortex (M1 after training. By contrast, the mean magnitude of neural activation remained unchanged. Therefore, our study suggests that learning shapes the brain by increasing the stability of the activation patterns, therefore providing a new perspective in understanding the neural mechanisms underlying learning.

  10. [Runoff Pollution Experiments of Paddy Fields Under Different Irrigation Patterns].

    Zhou, Jing-wen; Su, Bao-lin; Huang, Ning-bo; Guan, Yu-tang; Zhao, Kun

    2016-03-15

    To study runoff and non-point source pollution of paddy fields and to provide a scientific basis for agricultural water management of paddy fields, paddy plots in the Jintan City and the Liyang City were chosen for experiments on non-point source pollution, and flood irrigation and intermittent irrigation patterns were adopted in this research. The surface water level and rainfall were observed during the growing season of paddies, and the runoff amount from paddy plots and loads of total nitrogen (TN) and total phosphorus (TP) were calculated by different methods. The results showed that only five rain events of totally 27 rainfalls and one artificially drainage formed non-point source pollution from flood irrigated paddy plot, which resulted in a TN export coefficient of 49.4 kg · hm⁻² and a TP export coefficient of 1.0 kg · hm⁻². No any runoff event occurred from the paddy plot with intermittent irrigation even in the case of maximum rainfall of 95.1 mm. Runoff from paddy fields was affected by water demands of paddies and irrigation or drainage management, which was directly correlated to surface water level, rainfall amount and the lowest ridge height of outlets. Compared with the flood irrigation, intermittent irrigation could significantly reduce non-point source pollution caused by rainfall or artificial drainage. PMID:27337888

  11. Agricultural activity shapes the communication and migration patterns in Senegal

    Martin-Gutierrez, S.; Borondo, J.; Morales, A. J.; Losada, J. C.; Tarquis, A. M.; Benito, R. M.

    2016-06-01

    The communication and migration patterns of a country are shaped by its socioeconomic processes. The economy of Senegal is predominantly rural, as agriculture employs over 70% of the labor force. In this paper, we use mobile phone records to explore the impact of agricultural activity on the communication and mobility patterns of the inhabitants of Senegal. We find two peaks of phone calls activity emerging during the growing season. Moreover, during the harvest period, we detect an increase in the migration flows throughout the country. However, religious holidays also shape the mobility patterns of the Senegalese people. Hence, in the light of our results, agricultural activity and religious holidays are the primary drivers of mobility inside the country.

  12. PHYSIOLOGIC PATTERNS OF SLEEP ON EEG, MASKING OF EPILEPTIFORM ACTIVITY

    L. Yu. Glukhova

    2013-01-01

    Full Text Available Physiologic patterns of sleep on EEG can sometimes be similar to epileptiform activity and even to the EEG pattern of epileptic seizures, but they have no connection to epilepsy and their incorrect interpretation may lead to overdiagnosis of epilepsy. These sleep patterns include vertex transients, K-complexes, hypnagogic hypersynchrony, 14 and 6 Hz positive bursts, wicket-potentials, etc. The main distinctive features of acute physiological phenomena of sleep unlike epileptiform activity are stereotyped, monomorphic morphology of waves, which frequently has rhythmic, arcuate pattern, often with change of lateralization, mainly dominated in the first stages of sleep (N1-N2, with their reduction in the deeper stages and transition to delta sleep (N3. The correct interpretation of physiological sharp-wave phenomena of sleep on EEG requires considerable training and experience of the physician. Our review includes a variety of physiological sleep patterns, which can mimic epileptiform activity on EEG, their criteria of diagnostic with demonstration of own illustrations of EEG.

  13. Physical Activity Patterns among U.S. Adults with Disabilities

    Chiu, Chung-Yi; An, Ruopeng

    2016-01-01

    Purpose: To characterize physical activity patterns among people with disabilities using data from a nationally representative health survey. Method: Individual-level data came from the Behavioral Risk Factor Surveillance System 2011 survey. Pearson's chi-squared tests were conducted to assess the difference in the proportion distribution of…

  14. Invading the Mediterranean Sea: biodiversity patterns shaped by human activities

    Katsanevakis, Stelios; Coll, Marta; Piroddi, Chiara; STEENBEEK Jeroen; Ben Rais Lasram, Frida; Zenetos, Argyro; Cardoso, Ana Cristina

    2014-01-01

    Human activities, such as shipping, aquaculture, and the opening of the Suez Canal, have caused the introduction of nearly 1,000 alien species in the Mediterranean Sea. We investigated how human activities, offering pathways for the introduction of alien species, may shape the biodiversity patterns in the Mediterranean. Richness of Red Sea species introduced through the Suez Canal (Lessepsian species) is very high along the eastern Mediterranean coastline, reaching a maximum of 129 species pe...

  15. Extraembryonic signals under the control of MGA, Max, and Smad4 are required for dorsoventral patterning.

    Sun, Yuhua; Tseng, Wei-Chia; Fan, Xiang; Ball, Rebecca; Dougan, Scott T

    2014-02-10

    In vertebrates, extraembryonic tissues can act as signaling centers that impose a reproducible pattern of cell types upon the embryo. Here, we show that the zebrafish yolk syncytial layer (YSL) secretes a ventralizing signal during gastrulation. This activity is mediated by Bmp2b/Swirl (Swr) expressed under the control of Max's giant associated protein (MGA) and its binding partners, Max and Smad4. MGA coimmunoprecipitates with both Max and Smad4 in embryo extracts, and the three proteins form a complex in vitro. Furthermore, all three proteins bind to a DNA fragment upstream of the bmp2b transcription start site. Targeted depletion of MGA, its binding partners, or Bmp2b/Swr from the YSL reduces BMP signaling throughout the embryo, resulting in a mildly dorsalized phenotype. We conclude that MGA, Max, and Smad4 act in the extraembryonic YSL to initiate a positive feedback loop of Bmp signaling within the embryo. PMID:24525188

  16. Active Curved Polymers Form Vortex Patterns on Membranes

    Denk, Jonas; Huber, Lorenz; Reithmann, Emanuel; Frey, Erwin

    2016-04-01

    Recent in vitro experiments with FtsZ polymers show self-organization into different dynamic patterns, including structures reminiscent of the bacterial Z ring. We model FtsZ polymers as active particles moving along chiral, circular paths by Brownian dynamics simulations and a Boltzmann approach. Our two conceptually different methods point to a generic phase behavior. At intermediate particle densities, we find self-organization into vortex structures including closed rings. Moreover, we show that the dynamics at the onset of pattern formation is described by a generalized complex Ginzburg-Landau equation.

  17. Activity Patterns and Pollution Exposure. A Case Study of Melbourne

    In recent times there has been increasing interest in modelling policies to limit impacts of air pollution due to motor vehicles. Impacts of air pollution on human health and comfort depend on the relationship between the distribution of pollutants and the spatial distribution of the urban population. As emissions, weather conditions and the location of the population vary with time of day, day of month and season of the year, the problem is complex. Travel demand models with activity-based approaches and a focus on the overall structure of activity/travel relations, not only spatially, but temporally can make a valuable contribution. They are often used to estimate emissions due to the travel patterns of city populations but may equally be used to provide distributions of urban populations during the day. A case study for Melbourne, Australia demonstrates the use of activity data in the estimation of population exposure. Additionally the study shows some marked differences in activity between seasons and even greater the differences in effect of that activity on exposure to air pollution. Numbers of cities will have seasonal pollutant patterns similar to Melbourne and others will benefit from exploring such patterns

  18. Objectively Measured Activity Patterns among Adults in Residential Aged Care

    Natasha Reid

    2013-12-01

    Full Text Available Objectives: To determine the feasibility of using the activPAL3TM activity monitor, and, to describe the activity patterns of residential aged care residents. Design: Cross-sectional. Setting: Randomly selected aged care facilities within 100 km of the Gold Coast, Queensland, Australia. Participants: Ambulatory, older (≥60 years residential aged care adults without cognitive impairment. Measurements: Feasibility was assessed by consent rate, sleep/wear diary completion, and through interviews with staff/participants. Activity patterns (sitting/lying, standing, and stepping were measured via activPAL3TM monitors worn continuously for seven days. Times spent in each activity were described and then compared across days of the week and hours of the day using linear mixed models. Results: Consent rate was 48% (n = 41. Activity patterns are described for the 31 participants (mean age 84.2 years who provided at least one day of valid monitor data. In total, 14 (45% completed the sleep/wear diary. Participants spent a median (interquartile range of 12.4 (1.7 h sitting/lying (with 73% of this accumulated in unbroken bouts of ≥30 min, 1.9 (1.3 h standing, and 21.4 (36.7 min stepping during their monitored waking hours per day. Activity did not vary significantly by day of the week (p ≥ 0.05; stepping showed significant hourly variation (p = 0.018. Conclusions: Older adults in residential aged care were consistently highly sedentary. Feasibility considerations for objective activity monitoring identified for this population include poor diary completion and lost monitors.

  19. Circadian pattern and burstiness in human communication activity

    Jo, Hang-Hyun; Kertész, János; Kaski, Kimmo

    2011-01-01

    The temporal pattern of human communication is inhomogeneous and bursty, as reflected by the heavy tail distribution of the inter-event times. For the origin of this behavior two main mechanisms have been suggested: a) Externally driven inhomogeneities due to the circadian and weekly activity patterns and b) intrinsic correlation based inhomogeneity rooted deeply in the task handling strategies of humans. Here we address this question by providing systematic de-seasoning methods to remove the circadian and weekly patterns from the time series of communication events. We find that the heavy tails of the inter-event time distributions are robust with respect to this procedure indicating that burstiness is mostly caused by the latter mechanism b). Moreover, we find that our de-seasoning procedure improves the scaling behavior of the distribution.

  20. Communities in Neuronal Complex Networks Revealed by Activation Patterns

    Costa, Luciano da Fontoura

    2008-01-01

    Recently, it has been shown that the communities in neuronal networks of the integrate-and-fire type can be identified by considering patterns containing the beginning times for each cell to receive the first non-zero activation. The received activity was integrated in order to facilitate the spiking of each neuron and to constrain the activation inside the communities, but no time decay of such activation was considered. The present article shows that, by taking into account exponential decays of the stored activation, it is possible to identify the communities also in terms of the patterns of activation along the initial steps of the transient dynamics. The potential of this method is illustrated with respect to complex neuronal networks involving four communities, each of a different type (Erd\\H{o}s-R\\'eny, Barab\\'asi-Albert, Watts-Strogatz as well as a simple geographical model). Though the consideration of activation decay has been found to enhance the communities separation, too intense decays tend to y...

  1. Instabilities and patterns in an active nematic film

    Srivastava, Pragya; Marchetti, Cristina

    2015-03-01

    Experiments on microtubule bundles confined to an oil-water interface have motivated extensive theoretical studies of two-dimensional active nematics. Theoretical models taking into account the interplay between activity, flow and order have remarkably reproduced several experimentally observed features of the defect-dynamics in these ``living'' nematics. Here, we derive minimal description of a two-dimensional active nematic film confined between walls. At high friction, we eliminate the flow to obtain closed equations for the nematic order parameter, with renormalized Frank elastic constants. Active processes can render the ``Frank'' constants negative, resulting in the instability of the uniformly ordered nematic state. The minimal model yields emergent patterns of growing complexity with increasing activity, including bands and turbulent dynamics with a steady density of topological defects, as obtained with the full hydrodynamic equations. We report on the scaling of the length scales of these patterns and of the steady state number of defects with activity and system size. National Science Foundation grant DMR-1305184 and Syracuse Soft Matter Program.

  2. Patterns of adolescent physical activity and dietary behaviours

    Gorely Trish

    2009-07-01

    Full Text Available Abstract Background The potential synergistic effects of multiple dietary and physical activity behaviours on the risk of chronic conditions and health outcomes is a key issue for public health. This study examined the prevalence and clustering patterns of multiple health behaviours among a sample of adolescents in the UK. Methods Cross-sectional survey of 176 adolescents aged 12–16 years (49% boys. Adolescents wore accelerometers for seven days and completed a questionnaire assessing fruit, vegetable, and breakfast consumption. The prevalence of adolescents meeting the physical activity (≥ 60 minutes moderate-to-vigorous physical activity/day, fruit and vegetable (≥ 5 portions of FV per day and breakfast recommendations (eating breakfast on ≥ 5 days per week, and clustering patterns of these health behaviours are described. Results Boys were more active than girls (p Conclusion Many adolescents fail to meet multiple diet and physical activity recommendations, highlighting that physical activity and dietary behaviours do not occur in isolation. Future research should investigate how best to achieve multiple health behaviour change in adolescent boys and girls.

  3. Differences of fire activity and their underlying factors among vegetation formations in Greece

    Xystrakis F; Koutsias N

    2013-01-01

    Climate and weather play an important role in shaping fire activity patterns by controlling fuel productivity and fire spread, respectively. Additionally, climate is a key factor controlling primary productivity while different climate zones are expected to support different vegetation formations, that on their turn, include different fuel types. The use, therefore, of an underlying phytogeographical framework would provide more comprehensive outputs in exploring fire activity patterns at nat...

  4. Habitat Selection and Activity Pattern of GPS Collared Sumateran Tigers

    Dolly Priatna; Yanto Santosa; Lilik Budi Prasetyo; Agus Priyono Kartono

    2012-01-01

    Although translocation has been used in mitigating human-carnivore conflict for decades, few studies have been conducted on the behavioral ecology of released animals. Such information is necessary in the context of sustainable forest management. In this study we determine the type of land cover used as main habitat and examine the activity pattern of translocated tigers. Between 2008 and 2010 we captured six conflict tigers and translocated them 74-1,350 km from their capture sites in Sumate...

  5. Patterns of adolescent physical activity and dietary behaviours

    Gorely Trish; Biddle Stuart JH; Atkin Andrew J; Pearson Natalie; Edwardson Charlotte

    2009-01-01

    Abstract Background The potential synergistic effects of multiple dietary and physical activity behaviours on the risk of chronic conditions and health outcomes is a key issue for public health. This study examined the prevalence and clustering patterns of multiple health behaviours among a sample of adolescents in the UK. Methods Cross-sectional survey of 176 adolescents aged 12–16 years (49% boys). Adolescents wore accelerometers for seven days and completed a questionnaire assessing fruit,...

  6. Distributed patterns of brain activity that lead to forgetting

    Ilke eOztekin; David eBadre

    2011-01-01

    HUMAN NEUROSCIENCE Distributed patterns of brain activity that lead to forgetting Ilke Öztekin1* and David Badre2,3 1 Department of Psychology, Koç University, Istanbul, Turkey 2 Department of Cognitive, Linguistic and Psychological Sciences, Brown University, Providence, RI, USA 3 Brown Institute for Brain Sciences, Brown University, Providence, RI, USA Proactive interference (PI), in which irrelevant information from prior learning disrupts memory performance, is widely...

  7. The muscle activation patterns of lower limb during stair climbing at different backpack load.

    Yali, Han; Aiguo, Song; Haitao, Gao; Songqing, Zhu

    2015-01-01

    Stair climbing under backpack load condition is a challenging task. Understanding muscle activation patterns of lower limb during stair climbing with load furthers our understanding of the factors involved in joint pathology and the effects of treatment. At the same time, stair climbing under backpack load requires adjustments of muscle activations and increases joint moment compared to level walking, which with muscle activation patterns are altered as a result of using an assistive technology, such as a wearable exoskeleton leg for human walking power augmentation. Therefore, the aim of this study was to analyze lower limb muscles during stair climbing under different backpack load. Nine healthy volunteers ascended a four-step staircase at different backpack load (0 kg, 10 kg, 20 kg, 30 kg). Electromyographic (EMG) signals were recorded from four lower limb muscles (gastrocnemius, tibialis anterior, hamstring, rectus femoris). The results showed that muscle activation amplitudes of lower limb increase with increasing load during stair climbing, the maximum RMS of gastrocnemius are greater than tibialis anterior, hamstring and rectus femoris whether stair climbing or level walking under the same load condition. However, the maximum RMS of hamstring are smaller than gastrocnemius, tibialis anterior and rectus femoris. The study of muscle activation under different backpack load during stair climbing can be used to design biomechanism and explore intelligent control based on EMG for a wearable exoskeleton leg for human walking power augmentation. PMID:26899302

  8. a Multidisciplinary Analytical Framework for Studying Active Mobility Patterns

    Orellana, D.; Hermida, C.; Osorio, P.

    2016-06-01

    Intermediate cities are urged to change and adapt their mobility systems from a high energy-demanding motorized model to a sustainable low-motorized model. In order to accomplish such a model, city administrations need to better understand active mobility patterns and their links to socio-demographic and cultural aspects of the population. During the last decade, researchers have demonstrated the potential of geo-location technologies and mobile devices to gather massive amounts of data for mobility studies. However, the analysis and interpretation of this data has been carried out by specialized research groups with relatively narrow approaches from different disciplines. Consequently, broader questions remain less explored, mainly those relating to spatial behaviour of individuals and populations with their geographic environment and the motivations and perceptions shaping such behaviour. Understanding sustainable mobility and exploring new research paths require an interdisciplinary approach given the complex nature of mobility systems and their social, economic and environmental impacts. Here, we introduce the elements for a multidisciplinary analytical framework for studying active mobility patterns comprised of three components: a) Methodological, b) Behavioural, and c) Perceptual. We demonstrate the applicability of the framework by analysing mobility patterns of cyclists and pedestrians in an intermediate city integrating a range of techniques, including: GPS tracking, spatial analysis, auto-ethnography, and perceptual mapping. The results demonstrated the existence of non-evident spatial behaviours and how perceptual features affect mobility. This knowledge is useful for developing policies and practices for sustainable mobility planning.

  9. Habitat Selection and Activity Pattern of GPS Collared Sumateran Tigers

    Dolly Priatna

    2012-12-01

    Full Text Available Although translocation has been used in mitigating human-carnivore conflict for decades, few studies have been conducted on the behavioral ecology of released animals. Such information is necessary in the context of sustainable forest management. In this study we determine the type of land cover used as main habitat and examine the activity pattern of translocated tigers. Between 2008 and 2010 we captured six conflict tigers and translocated them 74-1,350 km from their capture sites in Sumatera. All tigers were fitted with global positioning system (GPS collars. The collars were set to fix 24-48 location coordinates per day.  All translocated tigers showed a preference for a certain habitat type within their new home range, and tended to select the majority of natural land cover type within the landscape as their main habitat, but the availability of natural forest habitat within the landscape remains essensial for their survival. The activity of male translocated tigers differed significantly between the six time intervals of 24 hours, and their most active periods were in the afternoon (14:00-18:00 hours and in the evening (18:00-22:00 hours. Despite being preliminary, the findings of this study-which was the first such study conducted in Sumatera-highlight the conservation value of tiger translocation and provide valuable information for improving future management of conflict tigers.Keywords: activity pattern, GPS collars, habitat selection, sumateran tiger, translocation

  10. National youth sedentary behavior and physical activity daily patterns using latent class analysis applied to accelerometry

    Evenson, Kelly R.; Wen, Fang; Hales, Derek; Herring, Amy H.

    2016-01-01

    Background Applying latent class analysis (LCA) to accelerometry can help elucidated underlying patterns. This study described the patterns of accelerometer-determined sedentary behavior and physical activity among youth by applying LCA to a nationally representative United States (US) sample. Methods Using 2003–2006 National Health and Nutrition Examination Survey data, 3998 youths 6–17 years wore an ActiGraph 7164 accelerometer for one week, providing > =3 days of wear for > =8 h/day from 6...

  11. Optical imaging of the propagation patterns of neural responses in the rat sensory cortex: comparison under two different anesthetic conditions.

    Hama, N; Ito, S-I; Hirota, A

    2015-01-22

    Although many studies have reported the influence of anesthetics on the shape of somatic evoked potential, none has evaluated the influence on the spatio-temporal pattern of neural activity in detail. It is practically impossible to analyze neural activities spatially, using conventional electrophysiological methods. Applying our multiple-site optical recording technique for measuring membrane potential from multiple-sites with a high time resolution, we compared the spatio-temporal pattern of the evoked activity under two different anesthetic conditions induced by urethane or α-chloralose. The somatic cortical response was evoked by electrical stimulation of the hindlimb, and the optical signals were recorded from the rat sensorimotor cortex stained with a voltage-sensitive dye (RH414). The evoked activity emerged in a restricted area and propagated in a concentric manner. The spatio-temporal pattern of the evoked activity was analyzed using isochrone maps. There were significant differences in the latency and propagation velocity of the evoked activity, as well as the full width at half maximum of optical signal between the two anesthetic conditions. Differences in the amplitude and the slope of the rising phase were not significant. PMID:25301752

  12. Stress and physiological, behavioral and performance patterns of children under varied air ion levels

    Fornof, K. T.; Gilbert, G. O.

    1988-12-01

    The possibility that individual differences in reactivity to stressors are a major factor underlying discordant results reported for air ion studies prompted an investigation of response patterns in school children under both normal indoor air ion levels and moderately increased negative air ion levels (4000±500/cm3). It was hypothesized that the impact of stressors is reduced with high negative air ionization, and that resultant changes in stress effects would be differentially exhibited according to the children's normal degree of stimulus reactivity. A counter-balanced, replicative, withinssubject design was selected, and the subjects were 12 environmentally sensitive, 1st 4th grade school children. In addition to monitoring stress effects on activity level, attention span, concentration to task and conceptual performance, measures were also made of urinary 5-hydroxyindole acetic acid levels and skin resistance response (SRR) to determine if changes extended to the physiological state. The cold water test was used to add physical stress and enable calculations of Lacey's autonomic lability scores (ALS) as indicators of individual reactivity. The results show main effects for air ions on both physiological parameters, with 48% less change in %SRR ( Pstress tolerance. Strong interactive effects for ALS x air ion condition appeared, with high and low ALS children reacting oppositely to negative air ions in measures of skin resistance level ( P<0.01), wrist activity ( P<0.01) and digit span backwards ( P<0.004). Thus individual differences in autonomic reactivity and the presence or absence of stressors appear as critical elements for internal validity, and in preventing consequent skewed results from obscuring progress in air ion research.

  13. Turing patterns in network-organized activator-inhibitor systems

    Nakao, Hiroya; Mikhailov, Alexander S.

    2010-07-01

    Turing instability in activator-inhibitor systems provides a paradigm of non-equilibrium self-organization; it has been extensively investigated for biological and chemical processes. Turing instability should also be possible in networks, and general mathematical methods for its treatment have been formulated previously. However, only examples of regular lattices and small networks were explicitly considered. Here we study Turing patterns in large random networks, which reveal striking differences from the classical behaviour. The initial linear instability leads to spontaneous differentiation of the network nodes into activator-rich and activator-poor groups. The emerging Turing patterns become furthermore strongly reshaped at the subsequent nonlinear stage. Multiple coexisting stationary states and hysteresis effects are observed. This peculiar behaviour can be understood in the framework of a mean-field theory. Our results offer a new perspective on self-organization phenomena in systems organized as complex networks. Potential applications include ecological metapopulations, synthetic ecosystems, cellular networks of early biological morphogenesis, and networks of coupled chemical nanoreactors.

  14. Atrial natriuretic peptide and feeding activity patterns in rats

    Oliveira M.H.A.

    1997-01-01

    Full Text Available This review presents historical data about atrial natriuretic peptide (ANP from its discovery as an atrial natriuretic factor (ANF to its role as an atrial natriuretic hormone (ANH. As a hormone, ANP can interact with the hypothalamic-pituitary-adrenal axis (HPA-A and is related to feeding activity patterns in the rat. Food restriction proved to be an interesting model to investigate this relationship. The role of ANP must be understood within a context of peripheral and central interactions involving different peptides and pathways

  15. Pattern matching based active optical sorting of colloids/cells

    We report active optical sorting of colloids/cells by employing a cross correlation based pattern matching technique for selection of the desired objects and thereafter sorting using dynamically controllable holographic optical traps. The problem of possible collision between the different sets of objects during sorting was avoided by raising one set of particles to a different plane. We also present the results obtained on using this approach for some representative applications such as sorting of silica particles of two different sizes, of closely packed colloids and of white blood cells and red blood cells from a mixture of the two. (paper)

  16. Patterns of wildfires and emissions under future climate conditions across the conterminous United States

    Hawbaker, T. J.; Zhu, Z.; Finney, M.; Riley, K. L.; Jolly, W. M.; Keane, R. E.; Reinhardt, E.

    2013-12-01

    Climate change is expected to result in increased wildfire occurrence and greenhouse gas emissions in the conterminous United States. To better understand potential changes and their impacts, we asked: How might such expected changes vary over space and time in the conterminous United States, and across different climate-change scenarios? We quantified baseline patterns of burned area and emissions using burn scars from 2001-2008. Then, we developed a simulation model to assess the influence of climate change on patterns of wildfire ignitions, spread, and emissions. The simulation model was calibrated using historic fire, weather, and climate data and then used to generate projections under the A1B, A2, and B1 climate-change scenarios. We defined typical fire years and extreme fire years as the 50th and 95th percentile of decadal area burned or emissions. Then, we evaluated simulated changes in burned area and emissions among the 2001-2010 and 2041-2050 decades. Across the conterminous United States, our simulations results showed that during a typical fire year, area burned increased 25-52% from 15,700 km2 and emissions increased 20-48% from a baseline level of 56.0 TgCO2-eq. Extreme fire years in the 2041-2050 decade were more extreme than in the baseline period, and area burned increased 65-85% from 31,700 km2 and emissions increased 49-142% from 92.7 TgCO2-eq. Projected changes in fire occurrence and emissions were minimal for the Great Plains, but substantial for the West and certain ecoregions in the East. These results suggest that future wildfire activities could play a larger role in terms of socioeconomic risks and the health and productivity of ecosystems, and that efforts designed to reduce greenhouse gas emissions will compete with potential carbon losses due to climate-driven increases in wildfire occurrence.

  17. Landscape pattern and transition under natural and anthropogenic disturbance in an arid region of northwestern China

    Zhang, Yu; Wang, Tianwei; Cai, Chongfa; Li, Chongguang; Liu, Yaojun; Bao, Yuze; Guan, Wuhong

    2016-02-01

    There is a pressing need to determine the relationships between driving variables and landscape transformations. Human activities shape landscapes and turn them into complex assemblages of highly diverse structures. Other factors, including climate and topography, also play significant roles in landscape transitions, and identifying the interactions among the variables is critical to environmental management. This study analyzed the configurations and spatial-temporal processes of landscape changes from 1998 to 2011 under different anthropogenic disturbances, identified the main variables that determine the landscape patterns and transitions, and quantified the relationships between pairs of driver sets. Landsat images of Baicheng and Tekes from 1998, 2006 and 2011 were used to classify landscapes by supervised classification. Redundancy analysis (RDA) and variation partitioning were performed to identify the main driving forces and to quantify the unique, shared, and total explained variation of the sets of variables. The results indicate that the proportions of otherwise identical landscapes in Baicheng and Tekes were very different. The area of the grassland in Tekes was much larger than that of the cropland; however, the differences between the grassland and cropland in Baicheng were not as pronounced. Much of the grassland in Tekes was located in an area that was near residents, whereas most of the grassland in Baicheng was far from residents. The slope, elevation, annual precipitation, annual temperature, and distance to the nearest resident were strong driving forces influencing the patterns and transitions of the landscapes. The results of the variation partitioning indicated complex interrelationships among all of the pairs of driver sets. All of the variable sets had significant explanatory roles, most of which had both unique and shared variations with the others. The results of this study can assist policy makers and planners in implementing sustainable

  18. Active spectral sensor evaluation under varying conditions

    Plant stress has been estimated by spectral signature using both passive and active sensors. As optical sensors measure reflected light from a target, changes in illumination characteristics critically affect sensor response. Active sensors are of benefit in minimizing uncontrolled illumination effe...

  19. Mechanisms underlying spontaneous glutamatergic activity in developing mouse retina

    Firl, Alana

    2014-01-01

    Throughout the developing nervous system, spontaneous oscillatory patterns of activity have been observed. The developing murine retina is no exception, where spontaneous activity manifests as spatially correlated waves of depolarizations. These retinal waves propagate between neighboring neurons within retinal layers during the two postnatal weeks just prior to eye-opening and development of the light response. Waves are necessary for the normal patterning of connections of the retinal proje...

  20. Homogeneous temporal activity patterns in a large online communication space

    Kaltenbrunner, Andreas; Moghnieh, Ayman; Meza, Rodrigo; Blat, Josep; López, Vicente

    2007-01-01

    The many-to-many social communication activity on the popular technology-news website Slashdot has been studied. We have concentrated on the dynamics of message production without considering semantic relations and have found regular temporal patterns in the reaction time of the community to a news-post as well as in single user behavior. The statistics of these activities follow log-normal distributions. Daily and weekly oscillatory cycles, which cause slight variations of this simple behavior, are identified. A superposition of two log-normal distributions can account for these variations. The findings are remarkable since the distribution of the number of comments per users, which is also analyzed, indicates a great amount of heterogeneity in the community. The reader may find surprising that only a few parameters allow a detailed description, or even prediction, of social many-to-many information exchange in this kind of popular public spaces.

  1. Turing Patterns in Estuarine Sediments by Microbiological Activity

    De Morais Mendonca Teles, Antonio

    2016-07-01

    The use of Turing mechanisms and lattice Lotka-Volterra model (LLV), also by means of the non-extensive statistical mechanics, can mathematically describe well the phenomena of clustering and their associated boundaries with fractal dimensionality, which occurs in various natural situations, among them, biogeochemical processes via microorganisms in estuarine and marine sediments on the planet Earth. The author did an experimental analysis in field work which took into account the spatial and temporal behavior of Turing patterns, in the form of microbial activity within estuarine subsurface sediments. We show we can find the characteristics of clustering and fractallity which are present in the dynamical LLV model and Turing patterns mechanisms, and the non-extensive statistical mechanics could be used to find the q-entropy (Sq), and other non-equilibrium statistical parameters of the studied estuarine (Caraís lagoon) subsurface biogeochemical system. In this paper, the author suggests that such kinds of subsurface ecological systems are of interest to Astrobiology because if we find Turing-type clustered geomorphological patterns, below meter scale, on the near subsurface and inside rocks at the surface of planet Mars, and also find non-equilibrium statistical parameters (temperature, [F], [C], [S], etc.), displaying Turing-type mechanism, in the aquatic environments of the internal seas of planets Jupiter's moon Europa and the internal global ocean of Saturn's moon Enceladus, that could mean that possible hypothetical biogeochemical activities are present in such places. This could be a bio-indicator tool. And with further studies we could find the q-entropy Sq to establish better defined statistical mechanical parameters for such environments and to refine models for their evolution, as we do on planet Earth.

  2. Elevational gradients in bird diversity in the Eastern Himalaya: An evaluation of distribution patterns and their underlying mechanisms

    Acharya, Bhoj Kumar; Sanders, Nathan J.; Vijayan, Lalitha; Chettri, Basundhara; Sanders, Nate

    2011-01-01

    BACKGROUND: Understanding diversity patterns and the mechanisms underlying those patterns along elevational gradients is critically important for conservation efforts in montane ecosystems, especially those that are biodiversity hotspots. Despite recent advances, consensus on the underlying causes......, or even the relative influence of a suite of factors on elevational diversity patterns has remained elusive.\

  3. Developmental regulation of spatio-temporal patterns of cortical circuit activation

    Trevor Charles Griffen

    2013-01-01

    Full Text Available Neural circuits are refined in an experience-dependent manner during early postnatal development. How development modulates the spatio-temporal propagation of activity through cortical circuits is poorly understood. Here we use voltage sensitive dye imaging (VSD to show that there are significant changes in the spatio-temporal patterns of intracortical signals in primary visual cortex from postnatal day 13 (P13, eye opening, to P28, the peak of the critical period for rodent visual cortical plasticity. Upon direct stimulation of layer 4 (L4, activity spreads to L2/3 and to L5 at all ages. However, while from eye opening to the peak of the critical period, the amplitude and persistence of the voltage signal decrease, peak activation is reached more quickly and the interlaminar gain increases with age. The lateral spread of activation within layers remains unchanged throughout the time window under analysis. These developmental changes in spatio-temporal patterns of intracortical circuit activation are mediated by differences in the contributions of excitatory and inhibitory synaptic components. Our results demonstrate that after eye opening the circuit in primary visual cortex is refined through a progression of changes that shape the spatio-temporal patterns of circuit activation. Signals become more efficiently propagated across layers through developmentally regulated changes in interlaminar gain.

  4. Evolutionary patterns of proteinase activity in attine ant fungus gardens

    Semenova, Tatyana; Hughes, David Peter; Boomsma, Jacobus Jan;

    2011-01-01

    of evolutionary more derived fungal symbionts. This notion is also supported by buffering capacities of fungus gardens at pH 5.2 being remarkably high, and suggests that the fungal symbiont actively helps to maintain garden acidity at this specific level. Metalloproteinases dominated the activity profiles....... Conclusions: Proteinase pH optima and buffering capacities of fungal symbionts appear to have evolved remarkable adaptations to living in obligate symbiosis with farming ants. Although the functional roles of serine and metalloproteinases in fungus gardens are unknown, the differential production...... hypothesized that fungal proteinase activity may have been under selection for efficiency and that different classes of proteinases might be involved. Results: We determined proteinase activity profiles across a wide pH range for fungus gardens of 14 Panamanian species of fungus-growing ants, representing...

  5. Root activity distribution pattern of Ganesh pomegranate (Punica granatum) seedlings

    In one-year old Ganesh pomegranate seedlings raised on a loamy sand (Typic Haplustalf) under rain fed conditions, during winter (January-March) one-half of the active roots (44-51%) resided at 50 cm radial distance. Depth wise, bulk (44-78%) of the roots were found at 15 cm depth. The results indicate that the zone of high root activity is located around 50 cm distance from trunk and applications of fertilizers in this zone may lead to enhanced use efficiency of fertilizers. (author)

  6. A novel meta-analytic approach: mining frequent co-activation patterns in neuroimaging databases.

    Caspers, Julian; Zilles, Karl; Beierle, Christoph; Rottschy, Claudia; Eickhoff, Simon B

    2014-04-15

    In recent years, coordinate-based meta-analyses have become a powerful and widely used tool to study co-activity across neuroimaging experiments, a development that was supported by the emergence of large-scale neuroimaging databases like BrainMap. However, the evaluation of co-activation patterns is constrained by the fact that previous coordinate-based meta-analysis techniques like Activation Likelihood Estimation (ALE) and Multilevel Kernel Density Analysis (MKDA) reveal all brain regions that show convergent activity within a dataset without taking into account actual within-experiment co-occurrence patterns. To overcome this issue we here propose a novel meta-analytic approach named PaMiNI that utilizes a combination of two well-established data-mining techniques, Gaussian mixture modeling and the Apriori algorithm. By this, PaMiNI enables a data-driven detection of frequent co-activation patterns within neuroimaging datasets. The feasibility of the method is demonstrated by means of several analyses on simulated data as well as a real application. The analyses of the simulated data show that PaMiNI identifies the brain regions underlying the simulated activation foci and perfectly separates the co-activation patterns of the experiments in the simulations. Furthermore, PaMiNI still yields good results when activation foci of distinct brain regions become closer together or if they are non-Gaussian distributed. For the further evaluation, a real dataset on working memory experiments is used, which was previously examined in an ALE meta-analysis and hence allows a cross-validation of both methods. In this latter analysis, PaMiNI revealed a fronto-parietal "core" network of working memory and furthermore indicates a left-lateralization in this network. Finally, to encourage a widespread usage of this new method, the PaMiNI approach was implemented into a publicly available software system. PMID:24365675

  7. Patterns of Activity in a Global Model of a Solar Active Region

    Bradshaw, S. J.; Viall, N. M.

    2016-04-01

    In this work we investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of frequencies. What differs is the average frequency of the distributions. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine hydrodynamic and forward modeling codes with a magnetic field extrapolation to create a model active region and apply the time lag method to synthetic observations. Our aim is not to reproduce a particular set of observations in detail, but to recover some typical properties and patterns observed in active regions. Our key findings are the following. (1) Cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. (2) Shorter coronal loops in the core cool more quickly than longer loops at the periphery. (3) All channel pairs show zero time lag when the line of sight passes through coronal loop footpoints. (4) There is strong evidence that plasma must be re-energized on a timescale comparable to the cooling timescale to reproduce the observed coronal activity, but it is likely that a relatively broad spectrum of heating frequencies are operating across active regions. (5) Due to their highly dynamic nature, we find nanoflare trains produce zero time lags along entire flux tubes in our model active region that are seen between the same channel pairs in observed active regions.

  8. Self-organization of voids, gas bubbles and dislocation patterns under irradiation

    In the present paper three examples of self-organization in solids under irradiation are considered on the basis of original mechanisms, namely, the ordering of voids in void lattices under high temperature irradiation, the alignment of gas bubbles in bubble lattices under low-temperature gas atom implantation, and the formation of superdislocations (one-dimensional pile-ups of dislocation loops) and other dislocation patterns in the regimes of medium and high temperature irradiation. The ordering of cavities (i.e.voids or gas bubbles) is shown to arise due to a dissipative interaction between cavities induced by the interstitial dislocation loop absorption and punching, respectively, which represent anisotropic mechanisms of atomic transport. The dislocation patterning is shown to be driven by the dependence of dislocation bias for absorption of self-interstitial atoms on the dislocation arrangement. (author). 57 refs., 1 tab., 12 figs

  9. Spatial-Temporal Patterns in a Dielectric Barrier Discharge under Narrow Boundary Conditions in Argon at Atmospheric Pressure

    LI Xue-Chen; JIA Peng-Ying; ZHAO Na

    2011-01-01

    @@ Pattern formation phenomena are investigated in a dielectric barrier discharge under narrow boundary conditions in argon at atmospheric pressure.The discharge shows various scenarios with the increasing applied voltage.This is the first observation of alternating single spot and pair spots pattern and of a moving striation pattern in a dielectric barrier discharge system.The spatial-temporal correlations between discharge filaments in these patterns are measured by an optical method.The results show that the zigzag pattern is an interleaving of two sub-structure patterns, which ignites once for each sub-pattern per half cycle of the applied voltage.There is a temporal sequence inversion in consecutive half-cycles for the two sub-patterns.The pattern of alternating single spot and pair spots is also an interleaving of two sub-structure patterns.However, the pair spots sub-pattern ignites twice and the single spot sub-pattern ignites once per half cycle of the applied voltage.%Pattern formation phenomena are investigated in a dielectric barrier discharge under narrow boundary conditions in argon at atmospheric pressure. The discharge shows various scenarios with the increasing applied voltage.This is the first observation of alternating single spot and pair spots pattern and of a moving striation pattern in a dielectric barrier discharge system. The spatial-temporal correlations between discharge filaments in these patterns are measured by an optical method. The results show that the zigzag pattern is an interleaving of two sub-structure patterns, which ignites once for each sub-pattern per half cycle of the applied voltage. There is a temporal sequence inversion in consecutive half-cycles for the two sub-patterns. The pattern of alternating single spot and pair spots is also an interleaving of two sub-structure patterns. However, the pair spots sub-pattern ignites twice and the single spot sub-pattern ignites once per half cycle of the applied voltage.

  10. Market rewards to patterns of increasing earnings: effects of cash flow patterns, accruals manipulation, real activities manipulation and conservative accounting

    Liu, Su-Ping

    2013-01-01

    In this dissertation I investigate whether market rewards to a pattern of increasing earnings vary with certain signals of whether the pattern is genuine or fabricated. Among these signals, I examine growth in cash flows, accrual-based earnings management, earnings management through the manipulation of real operating activities, and conservative accounting. The findings show that market participants assign higher price-earnings multiples to firms when their pattern of increasi...

  11. Surface patterning of GaAs under irradiation with very heavy polyatomic Au ions

    Bischoff, L., E-mail: l.bischoff@hzdr.de; Böttger, R.; Heinig, K.-H.; Facsko, S.; Pilz, W.

    2014-08-15

    Self-organization of surface patterns on GaAs under irradiation with heavy polyatomic Au ions has been observed. The patterns depend on the ion mass, and the substrate temperature as well as the incidence angle of the ions. At room temperature, under normal incidence the surface remains flat, whereas above 200 °C nanodroplets of Ga appear after irradiation with monatomic, biatomic as well as triatomic Au ions of kinetic energies in the range of 10–30 keV per atom. In the intermediate temperature range of 100–200 °C meander- and dot-like patterns form, which are not related to Ga excess. Under oblique ion incidence up to 45° from the surface normal, at room temperature the surface remains flat for mon- and polyatomic Au ions. For bi- and triatomic ions in the range of 60° ≤ α ≤ 70° ripple patterns have been found, which become shingle-like for α ≥ 80°, whereas the surface remains flat for monatomic ions.

  12. Core regulatory network motif underlies the ocellar complex patterning in Drosophila melanogaster

    Aguilar-Hidalgo, D.; Lemos, M. C.; Córdoba, A.

    2015-03-01

    During organogenesis, developmental programs governed by Gene Regulatory Networks (GRN) define the functionality, size and shape of the different constituents of living organisms. Robustness, thus, is an essential characteristic that GRNs need to fulfill in order to maintain viability and reproducibility in a species. In the present work we analyze the robustness of the patterning for the ocellar complex formation in Drosophila melanogaster fly. We have systematically pruned the GRN that drives the development of this visual system to obtain the minimum pathway able to satisfy this pattern. We found that the mechanism underlying the patterning obeys to the dynamics of a 3-nodes network motif with a double negative feedback loop fed by a morphogenetic gradient that triggers the inhibition in a French flag problem fashion. A Boolean modeling of the GRN confirms robustness in the patterning mechanism showing the same result for different network complexity levels. Interestingly, the network provides a steady state solution in the interocellar part of the patterning and an oscillatory regime in the ocelli. This theoretical result predicts that the ocellar pattern may underlie oscillatory dynamics in its genetic regulation.

  13. Spike Train Dynamics Underlying Pattern Formation in Integrate-and-Fire Oscillator Networks

    Bressloff, P. C.; Coombes, S.

    1998-09-01

    A dynamical mechanism underlying pattern formation in a spatially extended network of integrate-and-fire oscillators with synaptic interactions is identified. It is shown how in the strong coupling regime the network undergoes a discrete Turing-Hopf bifurcation of the firing times from a synchronous state to a state with periodic or quasiperiodic variations of the interspike intervals on closed orbits. The separation of these orbits in phase space results in a spatially periodic pattern of mean firing rate across the network that is modulated by deterministic fluctuations of the instantaneous firing rate.

  14. Relative humidity and activity patterns of Ixodes scapularis (Acari: Ixodidae)

    Berger, K.A.; Ginsberg, Howard S.; Gonzalez, L.; Mather, T.N.

    2014-01-01

    Laboratory studies have shown clear relationships between relative humidity (RH) and the activity and survival of Ixodes scapularis Say (blacklegged tick). However, field studies have produced conflicting results. We examined this relationship using weekly tick count totals and hourly RH observations at three field sites, stratified by latitude, within the state of Rhode Island. Records of nymphal tick abundance were compared with several RH-related variables (e.g., RH at time of sampling and mean weekly daytime RH). In total, 825 nymphs were sampled in 2009, a year of greater precipitation, with a weighted average leaf litter RH recorded at time of sampling of 85.22%. Alternatively, 649 nymphs were collected in 2010, a year of relatively low precipitation, and a weighted average RH recorded at time of sampling was 75.51%. Negative binomial regression analysis of tick count totals identified cumulative hours <82% RH threshold as a significant factor observed in both years (2009: P = 0.0037; 2010: P < 0.0001). Mean weekly daytime RH did not significantly predict tick activity in either year. However, mean weekly daytime RH recorded with 1-wk lag before sample date was a significant variable (P = 0.0016) in 2010. These results suggest a lag effect between moisture availability and patterns of tick activity and abundance. Differences in the relative importance of each RH variable between years may have been due to abnormally wet summer conditions in 2009.

  15. Guiding catalytically active particles with chemically patterned surfaces

    Uspal, W E; Dietrich, S; Tasinkevych, M

    2016-01-01

    Catalytically active Janus particles suspended in solution create gradients in the chemical composition of the solution along their surfaces, as well as along any nearby container walls. The former leads to self-phoresis, while the latter gives rise to chemi-osmosis, providing an additional contribution to self-motility. Chemi-osmosis strongly depends on the molecular interactions between the diffusing chemical species and the wall. We show analytically, using an approximate "point-particle" approach, that by chemically patterning a planar substrate one can direct the motion of Janus particles: the induced chemi-osmotic flows can cause particles to either "dock" at the chemical step between the two materials, or to follow a chemical stripe. These theoretical predictions are confirmed by full numerical calculations. Generically, docking occurs for particles which tend to move away from their catalytic caps, while stripe-following occurs in the opposite case. Our analysis reveals the physical mechanisms governi...

  16. Decoding subjective mental states from fMRI activity patterns

    In recent years, functional magnetic resonance imaging (fMRI) decoding has emerged as a powerful tool to read out detailed stimulus features from multi-voxel brain activity patterns. Moreover, the method has been extended to perform a primitive form of 'mind-reading,' by applying a decoder 'objectively' trained using stimulus features to more 'subjective' conditions. In this paper, we first introduce basic procedures for fMRI decoding based on machine learning techniques. Second, we discuss the source of information used for decoding, in particular, the possibility of extracting information from subvoxel neural structures. We next introduce two experimental designs for decoding subjective mental states: the 'objective-to-subjective design' and the 'subjective-to-subjective design.' Then, we illustrate recent studies on the decoding of a variety of mental states, such as, attention, awareness, decision making, memory, and mental imagery. Finally, we discuss the challenges and new directions of fMRI decoding. (author)

  17. Agro-economic performance of mungbean intercropped in sesame under different planting patterns

    The performance of mungbean intercropped in sesame under different geometric arrangements was determined o sandy-clay loam soil at the university of Agriculture, Faisalabad for two consecutive years (2001-02). The planting patterns consisted of 40 cm spaced single rows, 60 cm spaced 3-row strips and 100 cm spaced 4-row strip while mungbean was intercropped in all the three planting patterns and also grown as a sole crop. The result evinced that planting sesame in 100 cm spaced 4-row strips explored the intercropping in sesame. It not only permitted convenient intercropping but also facilitated the harvesting and handling of intercrop without doing any damage to the base crop. Intercropping sesame with mungbean in the pattern of 100 cm spaced 4-row strips appeared to be more convenient, productive and profitable than the monocropped sesame. (author)

  18. Pattern formation in liquid-vapor systems under periodic potential and shear.

    Coclite, A; Gonnella, G; Lamura, A

    2014-06-01

    In this paper the phase behavior and pattern formation in a sheared nonideal fluid under a periodic potential is studied. An isothermal two-dimensional formulation of a lattice Boltzmann scheme for a liquid-vapor system with the van der Waals equation of state is presented and validated. Shear is applied by moving walls and the periodic potential varies along the flow direction. A region of the parameter space, where in the absence of flow a striped phase with oscillating density is stable, will be considered. At low shear rates the periodic patterns are preserved and slightly distorted by the flow. At high shear rates the striped phase loses its stability and traveling waves on the interface between the liquid and vapor regions are observed. These waves spread over the whole system with wavelength only depending on the length of the system. Velocity field patterns, characterized by a single vortex, will also be shown. PMID:25019908

  19. [Activity patterns and foraging behavior of Apis cerana cerana in the urban gardens in winter].

    Chen, Fa-jun; Yang, Qing-qing; Long, Li; Hu, Hong-mei; Duan, Bin; Chen, Wen-nian

    2016-01-01

    Bees and other pollinating insects are the important parts of biodiversity due to their great role in plant reproduction and crop production. To explore the role of city garden in native bees conservation, activity patterns, visiting behaviors and flowering plants with nectar or pollen were recorded in south Sichuan in winter. The results showed that, worker bees (Apis cerana cerana) were active to collect food out hive under suitable weather conditions, the duration of working was long. Peaks of the number of outgoing, entrance and foragers without pollen appeared at 14:00-15:00, and bimodal patterns were observed. While, peak of bees with pollen appeared at 11:00, and a unimodal pattern was observed. Time significantly affected the activity of workers. The workload of honey bees on nectar and pollen collection were different, just less than twenty percent foragers carrying pollen. Temperature and humidity also affected flights of bees to some degree, and bee activities showed similar patterns on different days. However, the activities had diverse characteristics in some time. Though a less number of plants were in flowering, most of them could be utilized by A. cerana cerana, and colonies could effectively get the food resource by behavior adjustment. In addition, visiting activities of bees on the flowers of main garden plants, such as Camellia japonica, showed obvious rhythm. Increasing the flowering plants with nectar and pollen in winter by scientific management of urban gardens would facilitate the creation of suitable habitats for A. cerana cerana and maintaining the wild population. PMID:27228619

  20. Pattern formation in directional solidification under shear flow. II. Morphologies and their characterization

    In the preceding paper, we have established an interface equation for directional solidification under the influence of a shear flow parallel to the interface. This equation is asymptotically valid near the absolute stability limit. The flow, described by a nonlocal term, induces a lateral drift of the whole pattern due to its symmetry-breaking properties. We find that at not-too-large flow strengths, the transcritical nature of the transition to hexagonal patterns shows up via a hexagonal modulation of the stripe pattern even when the linear instability threshold of the flowless case has not yet been attained. When the flow term is large, the linear description of the drift velocity breaks down and transitions to flow-dominated morphologies take place. The competition between flow-induced and diffusion-induced patterns (controlled by the temperature gradient) leads to new phenomena such as the transition to a different lattice structure in an array of hexagonal cells. Several methods to characterize the morphologies and their transitions are investigated and compared. In particular, we consider two different ways of defining topological defects useful in the description of patterns and we discuss how they are related to each other

  1. Exotic high activity surface patterns in PtAu nanoclusters

    Mokkath, Junais Habeeb

    2013-05-09

    The structure and chemical ordering of PtAu nanoclusters of 79, 135, and 201 atoms are studied via a combination of a basin hopping atom-exchange technique (to locate the lowest energy homotops at fixed composition), a symmetry orbit technique (to find the high symmetry isomers), and density functional theory local reoptimization (for determining the most stable homotop). The interatomic interactions between Pt and Au are derived from the empirical Gupta potential. The lowest energy structures show a marked tendency toward PtcoreAushell chemical ordering by enrichment of the more cohesive Pt in the core region and of Au in the shell region. We observe a preferential segregation of Pt atoms to (111) facets and Au atoms to (100) facets of the truncated octahedron cluster motif. Exotic surface patterns are obtained particularly for Pt-rich compositions, where Pt atoms are being surrounded by Au atoms. These surface arrangements boost the catalytic activity by creating a large number of active sites. © 2013 American Chemical Society.

  2. Duration in and Pattern of Utilization Under Children's Health Insurance Programs

    Lin, Chyongchiou J.; Lave, Judith R.

    1998-01-01

    This article provides information on duration of enrollment and utilization under children's health insurance programs for States planning to expand such programs in response to the Balanced Budget Act of 1997. Using data from children's health insurance programs in Pennsylvania, we find that there is a significant turnover among enrollees and the pattern of use following enrollment suggests considerable pent-up demand for medical services. The annual payment per child for services with a com...

  3. A scanning electron microscopic study of the patterns of external root resorption under different conditions

    Ravindran Sreeja; Chaudhary Minal; Tumsare Madhuri; Patil Swati; Wadhwan Vijay

    2009-01-01

    Objective: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. Material and Methods: A total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging fr...

  4. Connectivity, excitability and activity patterns in neuronal networks

    Extremely synchronized firing patterns such as those observed in brain diseases like epilepsy may result from excessive network excitability. Although network excitability is closely related to (excitatory) connectivity, a direct measure for network excitability remains unavailable. Several methods currently exist for estimating network connectivity, most of which are related to cross-correlation. An example is the conditional firing probability (CFP) analysis which calculates the pairwise probability (CFPi,j) that electrode j records an action potential at time t = τ, given that electrode i recorded a spike at t = 0. However, electrode i often records multiple spikes within the analysis interval, and CFP values are biased by the on-going dynamic state of the network. Here we show that in a linear approximation this bias may be removed by deconvoluting CFPi,j with the autocorrelation of i (i.e. CFPi,i), to obtain the single pulse response (SPRi,j)—the average response at electrode j to a single spike at electrode i. Thus, in a linear system SPRs would be independent of the dynamic network state. Nonlinear components of synaptic transmission, such as facilitation and short term depression, will however still affect SPRs. Therefore SPRs provide a clean measure of network excitability. We used carbachol and ghrelin to moderately activate cultured cortical networks to affect their dynamic state. Both neuromodulators transformed the bursting firing patterns of the isolated networks into more dispersed firing. We show that the influence of the dynamic state on SPRs is much smaller than the effect on CFPs, but not zero. The remaining difference reflects the alteration in network excitability. We conclude that SPRs are less contaminated by the dynamic network state and that mild excitation may decrease network excitability, possibly through short term synaptic depression. (papers)

  5. Differential Activation Patterns of fMRI in Sleep-Deprived Brain: Restoring Effects of Acupuncture

    Lei Gao

    2014-01-01

    Full Text Available Previous studies suggested a remediation role of acupuncture in insomnia, and acupuncture also has been used in insomnia empirically and clinically. In this study, we employed fMRI to test the role of acupuncture in sleep deprivation (SD. Sixteen healthy volunteers (8 males were recruited and scheduled for three fMRI scanning procedures, one following the individual’s normal sleep and received acupuncture SP6 (NOR group and the other two after 24 h of total SD with acupuncture on SP6 (SD group or sham (Sham group. The sessions were counterbalanced approximately two weeks apart. Acupuncture stimuli elicited significantly different activation patterns of three groups. In NOR group, the right superior temporal lobe, left inferior parietal lobule, and left postcentral gyrus were activated; in SD group, the anterior cingulate cortex, bilateral insula, left basal ganglia, and thalamus were significantly activated while, in Sham group, the bilateral thalamus and left cerebellum were activated. Different activation patterns suggest a unique role of acupuncture on SP6 in remediation of SD. SP6 elicits greater and anatomically different activations than those of sham stimuli; that is, the salience network, a unique interoceptive autonomic circuit, may indicate the mechanism underlying acupuncture in restoring sleep deprivation.

  6. Predicting brain activation patterns associated with individual lexical concepts based on five sensory-motor attributes.

    Fernandino, Leonardo; Humphries, Colin J; Seidenberg, Mark S; Gross, William L; Conant, Lisa L; Binder, Jeffrey R

    2015-09-01

    While major advances have been made in uncovering the neural processes underlying perceptual representations, our grasp of how the brain gives rise to conceptual knowledge remains relatively poor. Recent work has provided strong evidence that concepts rely, at least in part, on the same sensory and motor neural systems through which they were acquired, but it is still unclear whether the neural code for concept representation uses information about sensory-motor features to discriminate between concepts. In the present study, we investigate this question by asking whether an encoding model based on five semantic attributes directly related to sensory-motor experience - sound, color, visual motion, shape, and manipulation - can successfully predict patterns of brain activation elicited by individual lexical concepts. We collected ratings on the relevance of these five attributes to the meaning of 820 words, and used these ratings as predictors in a multiple regression model of the fMRI signal associated with the words in a separate group of participants. The five resulting activation maps were then combined by linear summation to predict the distributed activation pattern elicited by a novel set of 80 test words. The encoding model predicted the activation patterns elicited by the test words significantly better than chance. As expected, prediction was successful for concrete but not for abstract concepts. Comparisons between encoding models based on different combinations of attributes indicate that all five attributes contribute to the representation of concrete concepts. Consistent with embodied theories of semantics, these results show, for the first time, that the distributed activation pattern associated with a concept combines information about different sensory-motor attributes according to their respective relevance. Future research should investigate how additional features of phenomenal experience contribute to the neural representation of conceptual

  7. Patterns of Activity in a Global Model of a Solar Active Region

    Bradshaw, Stephen J

    2016-01-01

    In this work we investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of frequencies. What differs is the average frequency of the distributions. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine hydrodynamic and forward modeling codes with a magnetic field extrapolation to create a model active region and apply the time lag method to synthetic observations. Our aim is not to reproduce a particular set of observations in detail, but to recover some typical properties and patterns observed in active regions. Our key findings are the following. 1. cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. 2. shorter coronal loops in the core cool more quickly than longer loops at the periphery. 3. all channel pairs show zero time lag when the line-of-sight passes through coronal loop foot-points. 4. there ...

  8. Use of a relational reinforcement learning algorithm to generate dynamic activity-travel patterns

    VANHULSEL, Marlies; Janssens, Davy; Wets, Geert

    2007-01-01

    In the course of the past decade activity-based models have entered the area of transportation modelling. Such models simulate the generation of individual activity-travel patterns while deciding simultaneously on the different dimensions of activity-travel behaviour, such as the type of activity, the activity location, the transport mode used to reach this location, the starting time and duration of the activity, etc. However, as real-world activity-travel patterns prove not to be static due...

  9. Activity patterns of predator and prey : a simultaneous study of GPS-collared wolves and moose

    Eriksen, Ane; Wabakken, Petter; Zimmermann, Barbara; Andreassen, Harry P.; Arnemo, Jon Martin; Gundersen, Hege; Liberg, Olof; Linnell, John; Milner, Jos M.; Pedersen, Hans Christian; Sand, Håkan; Solberg, Erling J.; Storaas, Torstein

    2011-01-01

    We studied the simultaneous activity patterns of a breeding wolf, Canis lupus, pair and five adult moose, Alces alces, cows from April to November 2004 in a wolf territory in southeastern Norway. All study animals were GPS collared, and we used a total of 8297 fixes to analyse their temporal activity patterns. We examined the daily activity rhythm of the two species and how this varied seasonally through the study period, and investigated the association in activity patterns between the two s...

  10. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Jia, Guodong; Yu, Xinxiao; Fan, Dengxing; Jia, Jianbo

    2016-01-01

    Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r) functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono) and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined. PMID:27028757

  11. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Guodong Jia

    Full Text Available Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined.

  12. Patterns of Spontaneous Local Network Activity in Developing Cerebral Cortex: Relationship to Adult Cognitive Function.

    Alejandro Peinado

    potential underlying mechanism that could explain the observed differences in early spontaneous activity patterns.

  13. Patterned graphene functionalization via mask-free scanning of micro-plasma jet under ambient condition

    Ye, Dong; Yu, Yao, E-mail: ensiyu@mail.hust.edu.cn; Liu, Lin [School of Materials Science and Engineering, Huazhong University of Science and Technology, 430074 Wuhan (China); Wu, Shu-Qun; Lu, Xin-Pei [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, 430074 Wuhan (China); Wu, Yue [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3255 (United States)

    2014-03-10

    In this work, a mask-free method is introduced for patterned nitrogen doping of graphene using a micro-plasma jet under ambient condition. Raman and X-ray photoelectron spectroscopy spectra indicate that nitrogen atoms are incorporated into the graphene lattice with the two-dimensional spatial distribution precisely controlled in the range of mm down to 10 μm. Since the chemistry of the micro-plasma jet can be controlled by the choice of the gas mixture, this direct writing process with micro-plasma jet can be a versatile approach for patterned functionalization of graphene with high spatial resolution. This could have promising applications in graphene-based electronics.

  14. Effects of Levy Flights Mobility Pattern on Epidemic Spreading under Limited Energy Constraint

    Hu, Yanqing; Xu, Xiaoke; Han, Zhangang; Di, Zengru

    2010-01-01

    Recently, many empirical studies uncovered that animal foraging, migration and human traveling obey Levy flights with an exponent around -2. Inspired by the deluge of H1N1 this year, in this paper, the effects of Levy flights' mobility pattern on epidemic spreading is studied from a network perspective. We construct a spatial weighted network which possesses Levy flight spatial property under a restriction of total energy. The energy restriction is represented by the limitation of total travel distance within a certain time period of an individual. We find that the exponent -2 is the epidemic threshold of SIS spreading dynamics. Moreover, at the threshold the speed of epidemics spreading is highest. The results are helpful for the understanding of the effect of mobility pattern on epidemic spreading.

  15. Documenting Western Burrowing Owl Reproduction and Activity Patterns Using Motion-Activated Cameras

    Hall, Derek B. [NSTec; Greger, Paul D. [NSTec

    2014-08-01

    We used motion-activated cameras to monitor the reproduction and patterns of activity of the Burrowing Owl (Athene cunicularia) above ground at 45 burrows in south-central Nevada during the breeding seasons of 1999, 2000, 2001, and 2005. The 37 broods, encompassing 180 young, raised over the four years represented an average of 4.9 young per successful breeding pair. Young and adult owls were detected at the burrow entrance at all times of the day and night, but adults were detected more frequently during afternoon/early evening than were young. Motion-activated cameras require less effort to implement than other techniques. Limitations include photographing only a small percentage of owl activity at the burrow; not detecting the actual number of eggs, young, or number fledged; and not being able to track individual owls over time. Further work is also necessary to compare the accuracy of productivity estimates generated from motion-activated cameras with other techniques.

  16. A bacterial tyrosine phosphatase inhibits plant pattern recognition receptor activation

    Perception of pathogen-associated molecular patterns (PAMPs) by surface-localised pattern-recognition receptors (PRRs) is a key component of plant innate immunity. Most known plant PRRs are receptor kinases and initiation of PAMP-triggered immunity (PTI) signalling requires phosphorylation of the PR...

  17. Short communication: Assessment of activity patterns of growing rabbits in a flux-controlled chamber

    Irene Olivas

    2013-06-01

    Full Text Available Flux-controlled and metabolic chambers are often used for nutritional and environmental studies. However, the potential alterations of animal behaviour and welfare are so far not fully understood. In consequence, this study had 2 main objectives: to assess potential alterations of animal activity pattern and time budget inside a flux chamber, and to assess the importance of the “rearing up” behaviour. To this end, 10 growing rabbits of different ages (from 1 to 5 wk of the growing period were housed inside a flux chamber. Their activity was continuously recorded and assessed, determining the frequency and duration of 8 different behaviours: lying, sleeping, sitting, eating, drinking, walking, rearing up and others. Nocturnal rabbit behaviour and time budget were not altered inside the chamber if compared to previously described rabbit activity under conventional cages. In addition, rabbits in this experiment presented a tendency to perform “rearing up” when housed inside the flux chamber.

  18. Integrative Inferences on Pattern Geometries of Grapes Grown under Water Stress and Their Resulting Wines

    Hsieh, Fushing; Hsueh, Chih-Hsin; Heitkamp, Constantin; Matthews, Mark

    2016-01-01

    Multiple datasets of two consecutive vintages of replicated grape and wines from six different deficit irrigation regimes are characterized and compared. The process consists of four temporal-ordered signature phases: harvest field data, juice composition, wine composition before bottling and bottled wine. A new computing paradigm and an integrative inferential platform are developed for discovering phase-to-phase pattern geometries for such characterization and comparison purposes. Each phase is manifested by a distinct set of features, which are measurable upon phase-specific entities subject to the common set of irrigation regimes. Throughout the four phases, this compilation of data from irrigation regimes with subsamples is termed a space of media-nodes, on which measurements of phase-specific features were recoded. All of these collectively constitute a bipartite network of data, which is then normalized and binary coded. For these serial bipartite networks, we first quantify patterns that characterize individual phases by means of a new computing paradigm called “Data Mechanics”. This computational technique extracts a coupling geometry which captures and reveals interacting dependence among and between media-nodes and feature-nodes in forms of hierarchical block sub-matrices. As one of the principal discoveries, the holistic year-factor persistently surfaces as the most inferential factor in classifying all media-nodes throughout all phases. This could be deemed either surprising in its over-arching dominance or obvious based on popular belief. We formulate and test pattern-based hypotheses that confirm such fundamental patterns. We also attempt to elucidate the driving force underlying the phase-evolution in winemaking via a newly developed partial coupling geometry, which is designed to integrate two coupling geometries. Such partial coupling geometries are confirmed to bear causal and predictive implications. All pattern inferences are performed with

  19. Urban-rural differences in daily time-activity patterns, occupational activity and housing characteristics

    Matz, Carlyn J.; Stieb, David M.; Brion, Orly

    2015-01-01

    Background There is evidence that rural residents experience a health disadvantage compared to urban residents, associated with a greater prevalence of health risk factors and socioeconomic differences. We examined differences between urban and rural Canadians using data from the Canadian Human Activity Pattern Survey (CHAPS) 2. Methods Data were collected from 1460 respondents in two rural areas (Haldimand-Norfolk, Ontario and Annapolis Valley-Kings County, Nova Scotia) and 3551 respondents ...

  20. Quorum activation at a distance: spatiotemporal patterns of gene regulation from diffusion of an autoinducer signal

    Dilanji, Gabriel; Langebrake, Jessica; Deleenheer, Patrick; Hagen, Stephen J.

    2012-02-01

    Bacteria in colonies coordinate gene regulation through the exchange of diffusible signal molecules known as autoinducers (AI). This ``quorum signaling'' often occurs in physically heterogeneous and spatially extended environments such as biofilms. Under these conditions the space and time scales for diffusion of the signal limit the range and timing of effective gene regulation. We expect that spatial and temporal patterns of gene expression will reflect physical environmental constraints as well as nonlinear transcriptional activation and feedback within the gene regulatory system. We have combined experiments and modeling to investigate how these spatiotemporal patterns develop. We embed engineered plasmid/GFP quorum sensor strains or wild type strains in a long narrow agar lane, and then introduce AI signal at one terminus of the lane. Diffusion of the AI initiates reporter expression along the length of the lane, extending to macroscopic distances of mm-cm. Resulting patterns are captured quantitatively by a mathematical model that incorporates logistic growth of the population, diffusion of AI, and nonlinear transcriptional activation. Our results show that a diffusing quorum signal can coordinate gene expression over distances of order 1cm on time scales of order 10 hrs.

  1. Interface dynamics under nonequilibrium conditions: from a self-propelled droplet to dynamic pattern evolution

    Chen, Yong-Jun

    2012-01-01

    In this article, we describe the instability of a contact line under nonequilibrium conditions mainly based on the results of our recent studies. Two experimental examples are presented: the self-propelled motion of a liquid droplet and spontaneous dynamic pattern formation. For the self-propelled motion of a droplet, we introduce an experiment in which a droplet of aniline sitting on an aqueous layer moves spontaneously at an air-water interface. The spontaneous symmetry breaking of Marangoni-driven spreading causes regular motion. In a circular Petri dish, the droplet exhibits either beeline motion or circular motion. On the other hand, we show the emergence of a dynamic labyrinthine pattern caused by dewetting of a metastable thin film from the air-water interface. The contact line between the organic phase and aqueous phase forms a unique spatio-temporal pattern characterized as a dynamic labyrinthine. Motion of the contact line is controlled by diffusion processes. We propose a theoretical model to inter...

  2. Optical properties of 2D fractional Talbot patterns under coherent EUV illumination

    We investigate optical properties of (2D) fractional Talbot patterns under illumination with EUV laser light. The fractional Talbot effect, due to spatial frequency multiplication, can enable patterning of micro and nano-structures with various feature sizes using a micro-scale pitch mask. The experiment is performed with a free-standing mask fabricated by focused ion beam milling and a highly coherent illumination at 46.9 nm wavelength generated by a compact capillary discharge Ne-like Argon laser. As a result of spatial frequency multiplication, structure density of a square array of apertures in the mask was increased by a factor of up to 9 at the recording plane. The depth of field of the fractional Talbot images has been investigated using Fresnel diffraction analysis. Added field distribution complexity caused by asymmetry of the 2D arrays was observed both in simulation and in the experiment. This approach could be useful for sub-micron structuring of 2D patterns for various applications including among others the fabrication of photonic crystals, quantum dots, and also of submicron-electronic devices. (paper)

  3. Characterisation of Evolving Patterns and Underlying Regimes of Hydroclimatic Extremes in Europe

    Hall, J.; Perdigão, R. A. P.

    2015-12-01

    The dominant factors influencing hydroclimatic extreme events in Europe vary considerably across both time and space. Therefore, it is difficult to discern the dominant processes that govern floods and droughts in Europe. However, by focusing on large-scale physical processes that span beyond the catchment scale and on associated scale interactions, new insights can be gained on the resulting regional spatial patters. By assembling and thoroughly analysing a new unique database, with over 5000 discharge gauging stations in Europe, with key physical principles in mind, a better understanding of the driving processes underlying hydroclimatic extreme events is obtained. For example, by taking into account different time scales, different regimes of the extreme hydrological patterns are identified and linked to large-scale climatic controls. The improved understanding of how hydroclimatic extremes respond to their underlying controls in space and time paves the way for progress in the estimation of regimes and changes in floods and droughts.

  4. Time Use Patterns between Maintenance, Subsistence and Leisure Activities: A Case Study in China

    Hui-fen, Zhou; Zhen-shan, Li; Dong-qian, Xue; Yang, Lei

    2012-01-01

    The Chinese government conducted its first time use survey of the activities of Chinese individuals in 2008. Activities were classified into three broad types, maintenance activities, subsistence activities and leisure activities. Time use patterns were defined by an individuals' time spent on maintenance, subsistence and leisure activities each…

  5. Spatio-temporal patterns of soil water storage under dryland agriculture at the watershed scale

    Ibrahim, Hesham M.; Huggins, David R.

    2011-07-01

    SummarySpatio-temporal patterns of soil water are major determinants of crop yield potential in dryland agriculture and can serve as the basis for delineating precision management zones. Soil water patterns can vary significantly due to differences in seasonal precipitation, soil properties and topographic features. In this study we used empirical orthogonal function (EOF) analysis to characterize the spatial variability of soil water at the Washington State University Cook Agronomy Farm (CAF) near Pullman, WA. During the period 1999-2006, the CAF was divided into three roughly equal blocks (A, B, and C), and soil water at 0.3 m intervals to a depth of 1.5 m measured gravimetrically at approximately one third of the 369 geo-referenced points on the 37-ha watershed. These data were combined with terrain attributes, soil bulk density and apparent soil conductivity (EC a). The first EOF generated from the three blocks explained 73-76% of the soil water variability. Field patterns of soil water based on EOF interpolation varied between wet and dry conditions during spring and fall seasons. Under wet conditions, elevation and wetness index were the dominant factors regulating the spatial patterns of soil water. As soil dries out during summer and fall, soil properties (EC a and bulk density) become more important in explaining the spatial patterns of soil water. The EOFs generated from block B, which represents average topographic and soil properties, provided better estimates of soil water over the entire watershed with larger Nash-Sutcliffe Coefficient of Efficiency (NSCE) values, especially when the first two EOFs were retained. Including more than the first two EOFs did not significantly increase the NSCE of soil water estimate. The EOF interpolation method to estimate soil water variability worked slightly better during spring than during fall, with average NSCE values of 0.23 and 0.20, respectively. The predictable patterns of stored soil water in the spring could

  6. [Soil physical and chemical characteristics under different vegetation restoration patterns in China south subtropical area].

    Kang, Bing; Liu, Shi-rong; Cai, Dao-xiong; Lu, Li-hua; He, Ri-ming; Gao, Yan-xia; Di, Wei-zhi

    2010-10-01

    This paper studied the change of soil physical and chemical properties under eleven vegetation restoration patterns (1 kind of secondary forest, 2 kinds of pure coniferous plantations, 5 kinds of evergreen broad-leaved plantations, 2 kinds of conifer and broad-leaved mixed plantations, and 1 kind of shrub) typical in Daqingshan of Guangxi. Obvious differences were observed in the soil physical and chemical properties under different vegetation restoration patterns. The soil physical properties were better in secondary forest but poorer in pure conifer plantations. Conifer and broad-leaved mixed plantations had lower soil bulk density, and their soil total porosity and water-holding capacity were higher than those in pure plantations. There were no significant differences in the soil porosity among the 5 evergreen broad-leaved plantations. Except that of soil total K, the contents of soil nutrients in secondary forest were higher than those in plantations, and the soil C/N ratio and pH value were relatively lower. Comparing with shrub, the 9 plantations had an obvious change in their soil nutrient contents, e. g. , the increase of soil total N and available K. The 2 pure coniferous plantations had lower soil nutrient contents, but after mixed planted with evergreen broad-leaved trees, their soil nutrient contents increased markedly, and the soil C/N ratio decreased. PMID:21328932

  7. Perfusion patterns of metastatic gastrointestinal stromal tumor lesions under specific molecular therapy

    Schlemmer, Marcus [Department of Internal Medicine III, University Hospitals-Grosshadern, Ludwig Maximilians University Munich, Marchioninistr. 15, 81377 Munich (Germany); Sourbron, Steven P. [Institute of Clinical Radiology, University Hospitals-Grosshadern, Ludwig Maximilians University Munich, Marchioninistr. 15, 81377 Munich (Germany); Schinwald, Nicole [Department of Internal Medicine III, University Hospitals-Grosshadern, Ludwig Maximilians University Munich, Marchioninistr. 15, 81377 Munich (Germany); Nikolaou, Konstantin; Becker, Christoph R.; Reiser, Maximilian F. [Institute of Clinical Radiology, University Hospitals-Grosshadern, Ludwig Maximilians University Munich, Marchioninistr. 15, 81377 Munich (Germany); Berger, Frank, E-mail: Frank.Berger@med.uni-muenchen.de [Institute of Clinical Radiology, University Hospitals-Grosshadern, Ludwig Maximilians University Munich, Marchioninistr. 15, 81377 Munich (Germany)

    2011-02-15

    Rationale and objective: The aim of this pilot study was the evaluation of CT perfusion patterns in metastatic GIST lesions under specific molecular therapy with sunitinib or imatinib both in responders and non-responders. Patients and methods: 24 patients with metastatic GIST under tyrosine kinase inhibition were retrospectively evaluated. A total of 46 perfusion and venous phase CT scans were acquired. Volume of distribution, blood flow, blood volume, permeability and hepatic perfusion index measurements of metastatic lesions were carried out. Lesions were classified as 'good response' or 'poor response' to therapy, and perfusion parameters were compared for these two types of lesions. Results: 24 patients were evaluated. In the extrahepatic abdominal lesions (N = 15), good responders showed significant lower perfusion values than poor responders (volume of distribution: 3.3 {+-} 2.0 vs. 13.0 {+-} 1.8 ml/100 ml, p = 0.001). The same tendency was observed in intrahepatic lesions (N = 31) (liver volume of distribution: 2.1 {+-} 0.3 vs. 7.1 {+-} 1.3 ml/100 ml, p = 0.003); (hepatic perfusion index: 24.3 {+-} 7.9 vs. 76.1 {+-} 1.5%, p = 0.0001). Conclusion: Our data indicate that there are characteristic perfusion patterns of metastatic GIST lesions showing a good or poor response to molecular pharmacotherapy. Perfusion should be further evaluated in cross-sectional imaging studies as a possible biomarker for treatment response in targeted therapies of GIST.

  8. The measurement of sedentary patterns and behaviors using the activPAL™ Professional physical activity monitor

    Epidemiological studies have associated the negative effects of sedentary time and sedentary patterns on health indices. However, these studies have used methodologies that do not directly measure the sedentary state. Recent technological developments in the area of motion sensors have incorporated inclinometers, which can measure the inclination of the body directly, without relying on self-report or count thresholds. This paper aims to provide a detailed description of methodologies used to examine a range of relevant variables, including sedentary levels and patterns from an inclinometer-based motion sensor. The activPAL Professional physical activity logger provides an output which can be interpreted and used without the need for further processing and additional variables were derived using a custom designed MATLAB® computer program. The methodologies described have been implemented on a sample of 44 adolescent females, and the results of a range of daily physical activity and sedentary variables are described and presented. The results provide a range of objectively measured and objectively processed variables, including total time spent sitting/lying, standing and stepping, number and duration of daily sedentary bouts and both bed hours and non-bed hours, which may be of interest when making association between physical activity, sedentary behaviors and health indices. (paper)

  9. Complement activation by ligand-driven juxtaposition of discrete pattern recognition complexes

    Degn, Søren E.; Kjaer, Troels R.; Kidmose, Rune T.; Jensen, Lisbeth; Hansen, Annette G.; Tekin, Mustafa; Jensenius, Jens C.; Andersen, Gregers R.; Thiel, Steffen

    2014-01-01

    Defining mechanisms governing translation of molecular binding events into immune activation is central to understanding immune function. In the lectin pathway of complement, the pattern recognition molecules (PRMs) mannan-binding lectin (MBL) and ficolins complexed with the MBL-associated serine proteases (MASP)-1 and MASP-2 cleave C4 and C2 to generate C3 convertase. MASP-1 was recently found to be the exclusive activator of MASP-2 under physiological conditions, yet the predominant oligomeric forms of MBL carry only a single MASP homodimer. This prompted us to investigate whether activation of MASP-2 by MASP-1 occurs through PRM-driven juxtaposition on ligand surfaces. We demonstrate that intercomplex activation occurs between discrete PRM/MASP complexes. PRM ligand binding does not directly escort the transition of MASP from zymogen to active enzyme in the PRM/MASP complex; rather, clustering of PRM/MASP complexes directly causes activation. Our results support a clustering-based mechanism of activation, fundamentally different from the conformational model suggested for the classical pathway of complement. PMID:25197071

  10. Transnational Islamic activism and radicalization : patterns, trends, and prognosticators.

    Colbaugh, Richard; Engi, Dennis; LaViolette, Randall A.; Spomer, Judith E.

    2010-06-01

    The research described in this report developed the theoretical and conceptual framework for understanding, recognizing, and anticipating the origins, dynamic mechanisms, perceptions, and social structures of Islamic social reform movements in the Muslim homeland and in diaspora communities. This research has revealed valuable insights into the dynamic mechanisms associated with reform movements and, as such, offers the potential to provide indications and warnings of impending violence. This study produced the following significant findings: (1) A framework for understanding Islamic radicalization in the context of Social Movement Theory was developed and implemented. This framework provides a causal structure for the interrelationships among the myriad features of a social movement. (2) The degree to which movement-related activity shows early diffusion across multiple social contexts is a powerful distinguisher of successful and unsuccessful social movements. Indeed, this measurable appears to have significantly more predictive power than volume of such activity and also more power than various system intrinsics. (3) Significant social movements can occur only if both the intra-context 'infectivity' of the movement exceeds a certain threshold and the inter-context interactions associated with the movement occur with a frequency that is larger than another threshold. Note that this is reminiscent of, and significantly extends, well-known results for epidemic thresholds in disease propagation models. (4) More in-depth content analysis of blogs through the lens of Argumentation Theory has the potential to reveal new insights into radicalization in the context of Social Movement Theory. This connection has the potential to be of value from two important perspectives - first, this connection has the potential to provide more in depth insights into the forces underlying the emergence of radical behavior and second, this connection may provide insights into

  11. Weighted Local Active Pixel Pattern (WLAPP for Face Recognition in Parallel Computation Environment

    Gundavarapu Mallikarjuna Rao

    2013-10-01

    Full Text Available Abstract  - The availability of multi-core technology resulted totally new computational era. Researchers are keen to explore available potential in state of art-machines for breaking the bearer imposed by serial computation. Face Recognition is one of the challenging applications on so ever computational environment. The main difficulty of traditional Face Recognition algorithms is lack of the scalability. In this paper Weighted Local Active Pixel Pattern (WLAPP, a new scalable Face Recognition Algorithm suitable for parallel environment is proposed.  Local Active Pixel Pattern (LAPP is found to be simple and computational inexpensive compare to Local Binary Patterns (LBP. WLAPP is developed based on concept of LAPP. The experimentation is performed on FG-Net Aging Database with deliberately introduced 20% distortion and the results are encouraging. Keywords — Active pixels, Face Recognition, Local Binary Pattern (LBP, Local Active Pixel Pattern (LAPP, Pattern computing, parallel workers, template, weight computation.  

  12. Muscle activation patterns in patients with recurrent shoulder instability

    Anju Jaggi

    2012-01-01

    Conclusion: The DEMG results suggest that increased activation of LD may play a role in both anterior and posterior shoulder instability; increased activation of PM may play a role in anterior instability.

  13. Large-scale climate patterns and precipitation in an arid endorheic region: linkage and underlying mechanism

    Shi, Pengfei; Yang, Tao; Zhang, Ke; Tang, Qiuhong; Yu, Zhongbo; Zhou, Xudong

    2016-04-01

    The interactions between a range of large-scale climate oscillations and their quantitative links with precipitation are basic prerequisites to understand the hydrologic cycle. Restricted by the current limited knowledge on underlying mechanisms, statistical methods (e.g. correlation methods) are often used rather than a physical-based model. However, available correlation methods generally fail to explain the interactions among a wide range of climate oscillations and associated effects on the water cycle. This study presents a new probabilistic analysis approach by means of a state-of-the-art Copula-based joint probability distribution to characterize the aggregated behaviors for large-scale climate patterns and their connections to precipitation. We applied this method to identify the complex connections between climate patterns (westerly circulation (WEC), El Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO)) and seasonal precipitation over a typical endorheic region, the Tarim River Basin in central Asia. Results show that the interactions among multiple climate oscillations are non-uniform in most seasons and phases. Certain joint extreme phases can significantly trigger extremes (flood and drought) owing to the amplification effect among climate oscillations. We further find that the connection is mainly due to the complex effects of climatic and topographical factors.

  14. Retinal waves coordinate patterned activity throughout the developing visual system

    Ackman, James B.; Burbridge, Timothy J.; Crair, Michael C.

    2012-01-01

    The morphologic and functional development of the vertebrate nervous system is initially governed by genetic factors and subsequently refined by neuronal activity. However, fundamental features of the nervous system emerge before sensory experience is possible. Thus, activity-dependent development occurring before the onset of experience must be driven by spontaneous activity, but the origin and nature of activity in vivo remains largely untested. Here we use optical methods to demonstrate in...

  15. Quantitative Assessment of Soil Health Under Different Planting Patterns and Soil Types

    BI Chun-Juan; CHEN Zhen-Lou; WANG Jun; ZHOU Dong

    2013-01-01

    Soil health assessment is an important step toward understanding the potential effects of agricultural practices on crop yield,quality and human health.The objectives of this study were to select a minimum data set for soil health evaluation from the physical,chemical and biological properties and environmental pollution characteristics of agricultural soil and to develop a soil health diagnosis model for determining the soil health status under different planting patterns and soil types in Chongming Island of Shanghai,China.The results showed that the majority of the farmland soils in Chongming Island were in poor soil health condition,accounting for 48.9% of the survey samples,followed by the medium healthy soil,accounting for 32.2% of the survey samples and mainly distributed in the central and mid-eastern regions of the island.The indicators of pH,total organic carbon,microbial biomass carbon and Cd exerted less influence on soil health,while the soil salinization and nitrate accumulation under a greenhouse cropping pattern and phosphate fertilizer shortage in the paddy field had limited the development of soil health.Dichlorodiphenyltrichloroethanes,hexachlorocyclohexanes and Hg contributed less to soil health index (SHI) and showed no significant difference among paddy field,greenhouse and open-air vegetable/watermelon fields.The difference of the SHI of the three soil types was significant at P=0.05.The paddy soil had the highest SHI values,followed by the gray alluvial soil,and the coastal saline soil was in a poor soil health condition,indicating a need to plant some salt-tolerant crops to effectively improve soil quality.

  16. Patterns of metabolic activity in the treatment of schizophrenia

    Six patients with chronic schizophrenia were studied with positron emission tomography (PET) before and after neuroleptic treatment, using fluorine-18-labeled fluorodeoxyglucose. After treatment, the mean whole-slice glucose metabolic rate at the level of the basal ganglia showed a 25% increase. However, patterns of frontal hypometabolism observed with the schizophrenic patients were not altered by medication. Pattern analysis using the fast Fourier transform was applied to a set of 422 images from a mixed group of normal, depressed, and schizophrenic subjects. Reconstruction of the images with low-frequency coefficients was excellent, reducing considerably the number of variables needed to characterize each image. Hierarchical cluster analysis categorized the transformed images according to anatomical level and subject group (patient versus control). The results suggest the utility of this procedure for the classification and characterization of metabolic PET images from psychiatric patients. 8 references, 3 figures, 1 table

  17. Mining Emerging Sequential Patterns for Activity Recognition in Body Sensor Networks

    Gu, Tao; Wang, Liang; Chen, Hanhua;

    2010-01-01

    Body Sensor Networks oer many applications in healthcare, well-being and entertainment. One of the emerging applications is recognizing activities of daily living. In this paper, we introduce a novel knowledge pattern named Emerging Sequential Pattern (ESP)|a sequential pattern that discovers...... signicant class dierences|to recognize both simple (i.e., sequential) and complex (i.e., interleaved and concurrent) activities. Based on ESPs, we build our complex activity models directly upon the sequential model to recognize both activity types. We conduct comprehensive empirical studies to evaluate and...

  18. Altered lower leg muscle activation patterns in patients with cerebral palsy during cycling on an ergometer

    Alves-Pinto, Ana; Blumenstein, Tobias; Turova, Varvara; Lampe, Renée

    2016-01-01

    Objective Cycling on a recumbent ergometer constitutes one of the most popular rehabilitation exercises in cerebral palsy (CP). However, no control is performed on how muscles are being used during training. Given that patients with CP present altered muscular activity patterns during cycling or walking, it is possible that an incorrect pattern of muscle activation is being promoted during rehabilitation cycling. This study investigated patterns of muscular activation during cycling on a recumbent ergometer in patients with CP and whether those patterns are determined by the degree of spasticity and of mobility. Methods Electromyographic (EMG) recordings of lower leg muscle activation during cycling on a recumbent ergometer were performed in 14 adult patients diagnosed with CP and five adult healthy participants. EMG recordings were done with an eight-channel EMG system built in the laboratory. The activity of the following muscles was recorded: Musculus rectus femoris, Musculus biceps femoris, Musculus tibialis anterior, and Musculus gastrocnemius. The degree of muscle spasticity and mobility was assessed using the Modified Ashworth Scale and the Gross Motor Function Classification System, respectively. Muscle activation patterns were described in terms of onset and duration of activation as well as duration of cocontractions. Results Muscle activation in CP was characterized by earlier onsets, longer periods of activation, a higher occurrence of agonist–antagonist cocontractions, and a more variable cycling tempo in comparison to healthy participants. The degree of altered muscle activation pattern correlated significantly with the degree of spasticity. Conclusion This study confirmed the occurrence of altered lower leg muscle activation patterns in patients with CP during cycling on a recumbent ergometer. There is a need to develop feedback systems that can inform patients and therapists of an incorrect muscle activation during cycling and support the training

  19. Companies’ market penetration and activity patterns in european market

    Liviu NEAMTU; Adina Claudia NEAMTU

    2007-01-01

    The strategy type at the company level has an impact upon the selection and implementation of the strategy at the business level. The international strategy at the company level is different from the international strategy at the business level through the diversification extension degree (both under the products aspect and under the geographic area aspect). The need to adopt an international strategy at the company level appears when the products or services level increases in the sense of i...

  20. Gene Expression Patterns Underlying the Reinstatement of Plasticity in the Adult Visual System

    Ettore Tiraboschi

    2013-01-01

    Full Text Available The nervous system is highly sensitive to experience during early postnatal life, but this phase of heightened plasticity decreases with age. Recent studies have demonstrated that developmental-like plasticity can be reactivated in the visual cortex of adult animals through environmental or pharmacological manipulations. These findings provide a unique opportunity to study the cellular and molecular mechanisms of adult plasticity. Here we used the monocular deprivation paradigm to investigate large-scale gene expression patterns underlying the reinstatement of plasticity produced by fluoxetine in the adult rat visual cortex. We found changes, confirmed with RT-PCRs, in gene expression in different biological themes, such as chromatin structure remodelling, transcription factors, molecules involved in synaptic plasticity, extracellular matrix, and excitatory and inhibitory neurotransmission. Our findings reveal a key role for several molecules such as the metalloproteases Mmp2 and Mmp9 or the glycoprotein Reelin and open up new insights into the mechanisms underlying the reopening of the critical periods in the adult brain.

  1. Physical Activity Patterns Among Latinos in the United States: Putting the Pieces Together

    Sandra A. Ham, MS

    2007-10-01

    Full Text Available IntroductionEstimates of participation in physical activity among Latinos are inconsistent across studies. To obtain better estimates and examine possible reasons for inconsistencies, we assessed 1 patterns of participation in various categories of physical activity among Latino adults, 2 changes in their activity patterns with acculturation, and 3 variations in their activity patterns by region of origin.MethodsUsing data from four national surveillance systems (the National Health and Nutrition Examination Survey, 1999–2002; the Behavioral Risk Factor Surveillance System, 2003; the National Household Travel Survey, 2001; and the National Health Interview Survey Cancer Supplement, 2000, we estimated the percentage of Latinos who participated at least once per week in leisure-time, household, occupational, or transportation-related physical activity, as well as in an active pattern of usual daily activity. We reported prevalences by acculturation measures and region of origin.ResultsThe percentage of Latinos who participated in the various types of physical activity ranged from 28.7% for having an active level of usual daily activity (usually walking most of the day and usually carrying or lifting objects to 42.8% for participating in leisure-time physical activity at least once per week. The percentage who participated in leisure-time and household activities increased with acculturation, whereas the percentage who participated in occupational and transportation-related activities decreased with acculturation. Participation in an active level of usual daily activity did not change significantly. The prevalence of participation in transportation-related physical activity and of an active level of usual daily activity among Latino immigrants varied by region of origin.ConclusionPhysical activity patterns among Latinos vary with acculturation and region of origin. To assess physical activity levels in Latino communities, researchers should

  2. Summary reports of activities under visiting research program (1994)

    This summary reports of activities under visiting research program in the Research Reactor Institute, Kyoto University, in fiscal year 1993 are included. In this report, 126 summaries of researches using the Kyoto University Reactor (KUR) and 12 summaries of the researches using the Kyoto University Critical Assembly (KUCA) are collected. (J.P.N.)

  3. Summary reports of activities under visiting research program (1993)

    The summary reports of activities under visiting research program in the Research Reactor Institute, Kyoto University, in fiscal year 1992 are included. In this report, 104 summaries of researches using the Kyoto University Reactor (KUR) and 9 summaries of the researches using the Kyoto University Critical Assembly (KUCA) are collected. (J.P.N.)

  4. epSICAR: An Emerging Patterns based Approach to Sequential, Interleaved and Concurrent Activity Recognition

    Gu, Tao; Wu, Zhanqing; Tao, Xianping; Pung, Hung Keng; Lu, Jian

    2009-01-01

    upon the training dataset for complex activities, we build our activity models by mining a set of Emerging Patterns from the sequential activity trace only and apply our models in recognizing sequential, interleaved and concurrent activities. We conduct our empirical studies in a real smart home...

  5. Object Relevance Weight Pattern Mining for Activity Recognition and Segmentation

    Palmes, Paulito Pedregosa; Pung, Hung Keng; Gu, Tao;

    2010-01-01

    Monitoring daily activities of a person has many potential benefits in pervasive computing. These include providing proactive support for the elderly and monitoring anomalous behaviors. A typical approach in existing research on activity detection is to construct sequence-based models of low-leve...

  6. The precise temporal pattern of pre-hearing spontaneous activity is necessary for tonotopic map refinement

    Clause, Amanda; Kim, Gunsoo; Sonntag, Mandy; Weisz, Catherine J.C.; Vetter, Douglas E.; Rübsamen, Rudolf; Kandler, Karl

    2014-01-01

    Patterned spontaneous activity is a hallmark of developing sensory systems. In the auditory system, rhythmic bursts of spontaneous activity are generated in cochlear hair cells and propagated along central auditory pathways. The role of these activity patterns in the development of central auditory circuits has remained speculative. Here we demonstrate that blocking efferent cholinergic neurotransmission to developing hair cells in mice that lack the α9 subunit of nicotinic acetylcholine rece...

  7. A comparative Study of Circulation Patterns at Active Lava Lakes

    Lev, Einat; Oppenheimer, Clive; Spampinato, Letizia; Hernandez, Pedro; Unglert, Kathi

    2016-04-01

    Lava lakes present a rare opportunity to study magma dynamics in a large scaled-up "crucible" and provide a unique natural laboratory to ground-truth dynamic models of magma circulation. The persistence of lava lakes allows for long-term observations of flow dynamics and of lava properties, especially compared to surface lava flows. There are currently five persistent lava lakes in the world: Halemaumau in Kilauea (Hawaii, USA), Erta Ale (Ethiopia), Nyiragongo (Congo), Erebus (Antarctica), and Villarica (Chile). Marum and Benbow craters of Ambrym volcano (Vanuatu) and Masaya (Nicaragua) have often hosted lava lakes as well. We use visible-light and thermal infrared time-lapse and video footage collected at all above lakes (except Villarica, where the lake is difficult to observe), and compare the circulation patterns recorded. We calculate lake surface motion from the footage using the optical flow method (Lev et al., 2012) to produce 2D velocity fields. We mined both the surface temperature field and the surface velocity field for patterns using machine learning techniques such as "self-organizing maps (SOMs)" and "principle component analysis (PCA)". We use automatic detection technique to study the configuration of crustal plates at the lakes' surface. We find striking differences among the lakes, in flow direction, flow speed, frequency of changes in flow direction and speed, location and consistency of upwelling and downwelling, and crustal plate configuration. We relate the differences to lake size, shallow conduit geometry, lava viscosity, crystal and gas content, and crust integrity.

  8. Patterns for election of active computing nodes in high availability distributed data acquisition systems

    Computer based systems for power plant and research reactors are expected to have high availability. Redundancy is a common approach to improve the availability of a system. In redundant configuration the challenge is to select one node as active, and in case of failure of current active node provide automatic fast switchover by electing another node to function as active and restore normal operation. Additional constraints include: exactly one node should be elected as active in an n-way redundant architecture. This paper discusses various high availability configurations developed by Electronics Division and deployed in power and research reactors and patterns followed to elect active nodes of distributed data acquisition systems. The systems are categorized into two: Active/Passive where changeover takes effect only on the failure of Active node, and Active/Active, where changeover is effective in alternate cycles. A novel concept of priority driven state based Active (Master) node election pattern is described for Active/Passive systems which allows multiple redundancy and dynamic election of single master. The paper also discusses the Active/Active pattern, which uncovers failure early by activating all the nodes alternatively in a redundant system. This pattern can be extended to multiple redundant nodes. (author)

  9. Cognitive load and autonomic response patterns under negative priming demand in depersonalization-derealization disorder.

    Lemche, Erwin; Sierra-Siegert, Mauricio; David, Anthony S; Phillips, Mary L; Gasston, David; Williams, Steven C R; Giampietro, Vincent P

    2016-04-01

    Previous studies have yielded evidence for cognitive processing abnormalities and alterations of autonomic functioning in depersonalization-derealization disorder (DPRD). However, multimodal neuroimaging and psychophysiology studies have not yet been conducted to test for functional and effective connectivity under cognitive stress in patients with DPRD. DPRD and non-referred control subjects underwent a combined Stroop/negative priming task, and the neural correlates of Stroop interference effect, negative priming effect, error rates, cognitive load span and average amplitude of skin conductance responses were ascertained for both groups. Evoked haemodynamic responses for basic Stroop/negative priming activations were compared. For basic Stroop to neutral contrast, patients with DPRD differed in the location (inferior vs. superior lobule) of the parietal region involved, but showed similar activations in the left frontal region. In addition, patients with DPRD also co-activated the dorsomedial prefrontal cortex (BA9) and posterior cingulate cortex (BA31), which were also found to be the main between-group difference regions. These regions furthermore showed connectivity with frequency of depersonalization states. Evoked haemodynamic responses drawn from regions of interest indicated significant between-group differences in 30-40% of time points. Brain-behaviour correlations differed mainly in laterality, yet only slightly in regions. A reversal of autonomic patterning became evident in patients with DPRD for cognitive load spans, indicating less effective arousal suppression under cognitive stress - patients with DPRD showed positive associations of cognitive load with autonomic responses, whereas controls exhibit respective inverse association. Overall, the results of the present study show only minor executive cognitive peculiarities, but further support the notion of abnormalities in autonomic functioning in patients with DPRD. PMID:26791018

  10. Physical Activity Patterns in the Elderly Kashan Population

    Sadrollahi, Ali; Hosseinian, Masoumeh; Masoudi Alavi, Negin; Khalili, Zahra; Esalatmanesh, Sophia

    2016-01-01

    Background Physical activity is an important component of health in old age that provides personal independence, physical ability, and quality of life. Objectives The current study aimed to evaluate physical activity and associated factors among the elderly population in Kashan, Iran. Patients and Methods This is a descriptive cross-sectional study. The sample was 400 elderly people (aged more than 60 years) living in Kashan, Iran in 2014. The subjects randomly selected via multi-stage cluster sampling from healthcare centers in three regions of Kashan. The sample size differed by gender and residence type. Each participant’s demographic characteristics and level of physical activity were recorded in a questionnaire, and the data were analyzed by SPSS version 16. Descriptive statistics, chi-square tests, Pearson correlations, and ordinal regression were used in the data analysis. The significance level for all the tests was P occupation (P health care planning for the elderly. PMID:27621923

  11. Modelling the emergence of spatial patterns of economic activity

    Yang, Jung-Hun; Frenken, Koen

    2012-01-01

    Understanding how spatial configurations of economic activity emerge is important when formulating spatial planning and economic policy. A simple model was proposed by Simon, who assumed that firms grow at a rate proportional to their size, and that new divisions of firms with certain probabilities relocate to other firms or to new centres of economic activity. Simon's model produces realistic results in the sense that the sizes of economic centres follow a Zipf distribution, which is also observed in reality. It lacks realism in the sense that mechanisms such as cluster formation, congestion (defined as an overly high density of the same activities) and dependence on the spatial distribution of external parties (clients, labour markets) are ignored. The present paper proposed an extension of the Simon model that includes both centripetal and centrifugal forces. Centripetal forces are included in the sense that firm divisions are more likely to settle in locations that offer a higher accessibility to other fi...

  12. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    De Fine Licht Henrik H

    2012-06-01

    Full Text Available Abstract Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae, wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily

  13. Gully Growth Patterns and Soil Loss under Rainfall at Urban Underground Drainage Construction Site, Uyo

    O.E. Essien

    2012-08-01

    Full Text Available This study investigated, evaluated and modeled patterns of growth of gully morphometric dimension and soil loss volume under prevailing rainfall on the slopes of land graded for the construction of underground drainage at Uyo but delayed in completion. Land grading at underground (tunnel drainage construction site rendered the exposed surface very impervious but young ephemeral gullies developed due to delays in completion. Data on gully morphometric dimension, soil loss and depth of rainfall were analyzed using SPSS ver. 17 statistical package. Mean gully growth in length, width and depth were different at 2.54±0.86, 0.923±0.29 and 0.41±0.11 m, respectively, yielding 3.87±0.08 m2 as mean volume of soil loss at full stage. Cubic polynomial was best-fit model for growth in length (R2 = 79% and width (R2 = 69% using weekly rainfall for an annual season. All gully sites had constant depth change, better predicted by quadratic (R2 = 13% than linear (R2 = 9% functions. Mean volume of soil loss per unit rainfall amount varied with low, medium and high rainfall amount and was highest at slope bottom (33 cm3/cm and least at the crest (6.99 cm3/cm with R2 = 38-34%. Land grading to impervious sublayer produced constant depth change in all gullies at the sites. The models for morphometric incremental growth and soil loss volume under the rainfall effect was significantly improved (p<0.05 by bifurcating the lumped annual curve into two growth periods in a year: the periods for increasing rainfall (from week 10-30 and for receding rainfall (from week 31-43 in a year and applying quadratic regressing functions on each (R2 = 91-99%. Rainfall was the principal gully factor and construction delays should be avoided.

  14. Adaptation of Salmonella enterica Hadar under static magnetic field: effects on outer membrane protein pattern

    Snoussi Sarra

    2012-02-01

    Full Text Available Abstract Background Salmonella enterica serovar Hadar (S. Hadar is a highly prevalent foodborne pathogen and therefore a major cause of human gastroenteritis worldwide. Outer membrane proteins whose production is often regulated by environmental conditions also play important roles in the adaptability of bacterial pathogens to various environments. Results The present study investigated the adaptation of S. Hadar under the effect of acute static magnetic field exposure (200 mT, 9 h and the impact on the outer membrane protein pattern. Via two-dimensional electrophoresis (2-DE and LC-MS/MS spectrometry, we compared the proteome of enriched-outer membrane fraction before and after exposure to a magnetic field. A total of 11 proteins, displaying more than a two-fold change, were differentially expressed in exposed cells, among which 7 were up-regulated and 4 down-regulated. These proteins were involved in the integrity of cell envelope (TolB, Pal, in the response to oxidative stress (OmpW, dihydrolipoamide dehydrogenase, UspF, in the oxidative stress status (bacterioferritin, in virulence (OmpX, Yfgl or in motility (FlgE and UspF. Complementary experiments associated the down-regulation of FlgE and UspF with an alteration of swarming, a flagella-driven motility, under SMF. Furthermore, the antibiotic disc diffusion method confirmed a decrease of gentamicin susceptibility in exposed cells. This decrease could be partly associated with the up-regulation of TolC, outer membrane component of an efflux pump. OmpA, a multifunctional protein, was up-regulated. Conclusions SMF (200 mT seems to maintain the cell envelope integrity and to submit the exposed cells to an oxidative stress. Some alterations suggest an increase of the ability of exposed cells to form biofilms.

  15. Identification of naphthoylindoles acting on cannabinoid receptors based on their fragmentation patterns under ESI-QTOFMS.

    Sekuła, Karolina; Zuba, Dariusz; Stanaszek, Roman

    2012-05-01

    'Herbal highs' have been advertised as legal and natural substitutes to cannabis, but a detailed examination of these products has revealed that the herbal matrix is laced with synthetic substances that mimic the effects of marijuana. Producers select the ingredients based on the results of scientific studies on the affinities of different chemicals to cannabinoid receptors. Naphthoylindoles have turned out to be the most popular class of substances identified in the products. Legal actions taken in order to tackle the problem of uncontrolled access to one substance have usually resulted in the marketing of derivatives or analogues. In the study, the mass spectral behavior of twelve synthetic cannabinoids from the naphthoylindole family under electrospray ionization (ESI) was investigated. LC-QTOFMS experiments were performed in three modes (low fragmentor voltage, high fragmentor voltage with/without collision energy), and they enabled the identification of protonated molecules and main ions. A general fragmentation pattern under this ionization method was proposed, and mechanisms of ion formation were discussed. The developed procedure allowed the determination of substituent groups of the core naphthoylindole structure and distinction between positional isomers. The obtained results were used for the prediction of the ESI-MS spectra for many naphthoylindoles with a high affinity to cannabinoid receptors. Similarities and differences between ESI-MS and electron impact-MS spectra of naphthoylindoles were discussed. The developed identification process was presented on an example of an analysis of an unknown herbal material, in which JWH-007 was finally identified. Knowledge of the fragmentation mechanisms of naphthoylindoles could also be used by other researchers for identification of unknown substances in this chemical family. PMID:22576877

  16. Proton nuclear magnetic resonance and pattern recognition analysis of liver extracts from rats under different anesthetics

    Although general anesthesia is widely used in the surgical arena, the mechanisms by which general anesthetics act remain unclear. We previously described alterations in gene expression ratios in hepatic tissue taken from rats treated with anesthetics. Consequently, it is considered that anesthetics influence liver metabolism. Thus, the goal of this study was to use pattern recognition analysis of proton nuclear magnetic resonance spectra to visualize changes in liver metabolic phenotypes in response to widely used intravenous anesthetics (propofol and dexmedetomidine) and inhalational anesthetics (sevoflurane and isoflurane). Rats were randomized into 13 groups (n = 6 in each group), and each group received one of following agents: propofol, dexmedetomidine, sevoflurane, isoflurane, or no anesthetic (control group). The liver was directly removed from rats immediately after or 24 h or 48 h after a 6-h period of anesthesia. Hydrophilic compounds were extracted from the liver and were analyzed with proton nuclear magnetic resonance spectroscopy. All spectral data were processed and analyzed by principal component analysis for comparison of metabolite profiles. Data were visualized by plotting principal component (PC) scores. In the plots, each point represents an individual sample. Each group was clustered separately on the plots, and the PC scores of the propofol group were clearly distinct from those of the control group and other anesthetic groups. The difference in PC scores was more pronounced immediately after completion of anesthesia when compared with 24 or 48 h after completion of anesthesia. Although the effect of intravenous anesthetics on the liver dissipated over time, the effect of inhalational anesthetics persisted. Propofol, dexmedetomidine, sevoflurane and isoflurane exert different effects on liver metabolism. In particular, liver metabolism was markedly altered after exposure to propofol. The effect of anesthesia on the liver under propofol or

  17. Activity patterns of cultured neural networks on micro electrode arrays

    Rutten, W.L.C.; Pelt, van J.

    2001-01-01

    A hybrid neuro-electronic interface is a cell-cultured micro electrode array, acting as a neural information transducer for stimulation and/or recording of neural activity in the brain or the spinal cord (ventral motor region or dorsal sensory region). It consists of an array of micro electrodes on

  18. Modeling Temporal Activity Patterns in Dynamic Social Networks

    Raghavan, Vasanthan; Galstyan, Aram; Tartakovsky, Alexander G

    2013-01-01

    The focus of this work is on developing probabilistic models for user activity in social networks by incorporating the social network influence as perceived by the user. For this, we propose a coupled Hidden Markov Model, where each user's activity evolves according to a Markov chain with a hidden state that is influenced by the collective activity of the friends of the user. We develop generalized Baum-Welch and Viterbi algorithms for model parameter learning and state estimation for the proposed framework. We then validate the proposed model using a significant corpus of user activity on Twitter. Our numerical studies show that with sufficient observations to ensure accurate model learning, the proposed framework explains the observed data better than either a renewal process-based model or a conventional uncoupled Hidden Markov Model. We also demonstrate the utility of the proposed approach in predicting the time to the next tweet. Finally, clustering in the model parameter space is shown to result in dist...

  19. Dietary and Physical Activity Pattern in Fars Province, National Plan of Chronic

    Mahin Farahmand

    2013-03-01

    Full Text Available Background: Changes in lifestyle, especially in different aspects of nutrition and physical activity, have been associated with change in the patterns of diseases, from contagious diseases to non-communicable diseases, and with the prevalence of chronic diseases. Accordingly, this study is carried out within the framework of National Plan to Care for Risk Factors of Non-communicable Diseases with the aim of comparing the dietary patterns and physical activity of people under study in Fars province during 2006-2007. Materials and Methods: Using the WHO Step-by-step Evaluation Model for Risky Factors, the present study determined fifty 20-person clusters, totally 1,000 people within the age group of 15-64 for each year as the research population. After identifying the applicable people, they were visited at their homes and the questionnaires were filled out for them. The necessary analysis was carried out using Version 6 of EPI-info and Version 10 of STATA software.Results: The findings of the present study indicated that men have more intense physical activity than women (p=0.001. The results also indicated a significant increase in consumption of fruit (p=0.01, vegetable (p=0.001, and fish (p=0.001 in 2007 as compared with 2006. The average number of the consumed vegetable units in women was higher than that of men (p=0.01.Conclusion: The findings of this study indicated that the average number of daily consumed units of fruit and vegetable as well as the frequencies of fish consumption per week was lower than the recommended amounts.

  20. Evaluation of Force Degradation Pattern of Elastomeric Ligatures and Elastomeric Separators in Active Tieback State

    Mohammadi, Amir; Mahmoodi, Farhang

    2015-01-01

    Background and aims. The purpose of this study was to evaluate initial force and force decay of commercially available elastomeric ligatures and elastomeric separators in active tieback state in a simulated oral environment. Materials and methods. A total of 288 elastomeric ligatures and elastomeric separators from three manufacturers (Dentaurum, RMO, 3M Unitek) were stretched to 100% and 150% of their original inner diameter. Force levels were measured initially and at 3-minute, 24-hour, and 1-, 2-, 3- and 4-week intervals. Data were analyzed by univariate analysis of variance and a post hoc Tukey test. Results. The means of initial forces of elastomeric ligatures and separators from three above-mentioned companies, when stretched to 100% of their inner diameters, were 199, 305 and 284 g, and 330, 416, 330 g; when they were stretched to 150% of their inner diameters the values were 286, 422 and 375 g, and 433, 540 and 504 g, respectively. In active tieback state, 11-18% of the initial force of the specimens was lost within the first 3 minutes and 29-63% of the force decay occurred in the first 24 hours; then force decay rate decreased. 62-81% of the initial force was lost in 4 weeks. Although force decay pattern was identical in all the products, the initial force and force decay of Dentaurum elastomeric products were less than the similar products of other companies (P<0.05). Under the same conditions, the force of elastomeric separators was greater than elastomeric ligatures of the same company. Conclusion. Regarding the force pattern of elastomeric ligatures and separators and optimal force for tooth movement, many of these products can be selected for applying orthodontic forces in active tieback state. PMID:26889363

  1. Dynamical pattern formation in a low-concentration magnetorheological fluid under two orthogonal sinusoidal fields

    Yépez, L. D.; Carrillo, J. L.; Donado, F.; Sausedo-Solorio, J. M.; Miranda-Romagnoli, P.

    2016-06-01

    The dynamical pattern formation of clusters of magnetic particles in a low-concentration magnetorheological fluid, under the influence of a superposition of two perpendicular sinusoidal fields, is studied experimentally. By varying the frequency and phase shift of the perpendicular fields, this configuration enables us to experimentally analyze a wide range of field configurations, including the case of a pure rotating field and the case of an oscillating unidirectional field. The fields are applied parallel to the horizontal plane where the fluid lies or in the vertical plane. For fields applied in the horizontal plane, we observed that, when the ratio of the frequencies increases, the average cluster size exhibits a kind of periodic resonances. When the phase shift between the fields is varied, the average chain length reaches maximal values for the cases of the rotating field and the unidirectional case. We analyze and discuss these results in terms of a weighted average of the time-dependent Mason number. In the case of a rotating field on the vertical plane, we also observe that the competition between the magnetic and the viscous forces determines the average cluster size. We show that this configuration generates a series of physically meaningful self-organization of clusters and transport phenomena.

  2. Concentration Dependent Ion-Protein Interaction Patterns Underlying Protein Oligomerization Behaviours

    Batoulis, Helena; Schmidt, Thomas H.; Weber, Pascal; Schloetel, Jan-Gero; Kandt, Christian; Lang, Thorsten

    2016-01-01

    Salts and proteins comprise two of the basic molecular components of biological materials. Kosmotropic/chaotropic co-solvation and matching ion water affinities explain basic ionic effects on protein aggregation observed in simple solutions. However, it is unclear how these theories apply to proteins in complex biological environments and what the underlying ionic binding patterns are. Using the positive ion Ca2+ and the negatively charged membrane protein SNAP25, we studied ion effects on protein oligomerization in solution, in native membranes and in molecular dynamics (MD) simulations. We find that concentration-dependent ion-induced protein oligomerization is a fundamental chemico-physical principle applying not only to soluble but also to membrane-anchored proteins in their native environment. Oligomerization is driven by the interaction of Ca2+ ions with the carboxylate groups of aspartate and glutamate. From low up to middle concentrations, salt bridges between Ca2+ ions and two or more protein residues lead to increasingly larger oligomers, while at high concentrations oligomers disperse due to overcharging effects. The insights provide a conceptual framework at the interface of physics, chemistry and biology to explain binding of ions to charged protein surfaces on an atomistic scale, as occurring during protein solubilisation, aggregation and oligomerization both in simple solutions and membrane systems. PMID:27052788

  3. Driving under the influence of alcohol in Cali, Colombia: prevalence and consumption patterns, 2013.

    Bonilla-Escobar, Francisco J; Herrera-López, Martha L; Ortega-Lenis, Delia; Medina-Murillo, Jhon J; Fandiño-Losada, Andrés; Jaramillo-Molina, Ciro; Naranjo-Lujan, Salome; Izquierdo, Edda P; Vanlaar, Ward; Gutiérrez-Martínez, María I

    2016-06-01

    This study's goal was to establish the prevalence of driving under the influence of alcohol (DUI) and alcohol consumption patterns among drivers in Cali, Colombia, in 2013. A cross-sectional study based on a roadside survey using a stratified and multi-stage sampling design was developed. Thirty-two sites were chosen randomly for the selection of drivers who were then tested for blood alcohol concentration (BAC) and asked to participate in the survey. The prevalence of DUI was 0.88% (95% confidence intervals [95% CI] 0.26%-1.49%) with a lower prevalence when BAC was increasing. In addition, a higher prevalence was found during non-typical checkpoint hours (1.28, 95% CI -0.001%-0.03%). The overall prevalence is considered high, given the low alcohol consumption and vehicles per capita. Prevention measures are needed to reduce DUI during non-typical checkpoints and ongoing studies are required to monitor the trends and enable the assessment of interventions. PMID:25563805

  4. Concentration Dependent Ion-Protein Interaction Patterns Underlying Protein Oligomerization Behaviours.

    Batoulis, Helena; Schmidt, Thomas H; Weber, Pascal; Schloetel, Jan-Gero; Kandt, Christian; Lang, Thorsten

    2016-01-01

    Salts and proteins comprise two of the basic molecular components of biological materials. Kosmotropic/chaotropic co-solvation and matching ion water affinities explain basic ionic effects on protein aggregation observed in simple solutions. However, it is unclear how these theories apply to proteins in complex biological environments and what the underlying ionic binding patterns are. Using the positive ion Ca(2+) and the negatively charged membrane protein SNAP25, we studied ion effects on protein oligomerization in solution, in native membranes and in molecular dynamics (MD) simulations. We find that concentration-dependent ion-induced protein oligomerization is a fundamental chemico-physical principle applying not only to soluble but also to membrane-anchored proteins in their native environment. Oligomerization is driven by the interaction of Ca(2+) ions with the carboxylate groups of aspartate and glutamate. From low up to middle concentrations, salt bridges between Ca(2+) ions and two or more protein residues lead to increasingly larger oligomers, while at high concentrations oligomers disperse due to overcharging effects. The insights provide a conceptual framework at the interface of physics, chemistry and biology to explain binding of ions to charged protein surfaces on an atomistic scale, as occurring during protein solubilisation, aggregation and oligomerization both in simple solutions and membrane systems. PMID:27052788

  5. Changing pattern of heavy rainstorms in the Indus basin of India under global warming scenarios

    N R Deshpande; B D Kulkarni

    2015-06-01

    Estimation of extremely high rainfall (point or areal) is one of the major components of design storm derivation. The estimation of Probable Maximum Precipitation (PMP) involves selection of heavy rain-storms and its maximization for the moisture content during the rainstorm period. These heavy rain-storms are nothing but the widespread heavy rainfall exceeding a certain threshold value. The present study examines the characteristics of heavy rainstorms in the Indus basin selected from present climate and future scenarios simulated by the regional climate model. Such information on heavy rainfall forms the basis for the hydrologic design projects and also for the water management of a river basin. Emphasis is given to severe rainstorms of 1-day duration covering an area of at least 40,000 km2 with spatial average rainfall of at least 5cm. This analysis also provides the information on the temporal changes in the storm factors such as shape, orientation, and movement, and shows that the model can well simulate the rainstorm pattern in terms of its intensity, orientation, and shape of the rainstorm, but overestimates the frequency of such heavy rainstorms. The future scenario indicates increase in rainfall intensity at the center of the rainstorm with decreasing areal spread. Decrease in the frequency of rainstorms is projected under the global warming conditions.

  6. Morphogenetic characteristics and demographic patterns of tillers on andropogon grass under different forage allowances

    Daniel Louçana da Costa Araújo

    2015-10-01

    Full Text Available The objective of this study was to evaluate the morphogenetic and structural characteristics and the demographic patterns of tillering in the grass Andropogon gayanus Kunth var. Bisquamulatus (Hochst Hack. cv. Planaltina subjected to three forage allowances: 11, 15 and 19% of the LW, under continuous grazing by goats. The experimental design for the evaluation of the pasture morphogenetic characteristics was set in (two random blocks, with six replications (tussocks within the block. To evaluate the tillering dynamics and population density, we adopted the experimental design of (two random blocks, in a split-plot arrangement. In the plots, we evaluated the effect of forage allowances and in the subplots, the months of April, May and June. Forage allowances did not affect the leaf elongation rate, leaf senescence or the number of live leaves. The leaf appearance rate was highest at the masses of 11 and 15% of the LW. Managing the pasture with a forage allowance of 19% of the LW increases the stem elongation rate, leaf lifespan and the lengths of leaf and stem. The number of vegetative tillers and the tiller appearance and survival rates are not affected by the forage allowances from 11 to 19% of the LW.

  7. Catalyst dispersion and activity under conditions of temperature- staged liquefaction

    Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

    1992-02-01

    The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experimental program will focus upon the development of effective methods of impregnating coal with catalysts, evaluating the conditions under which the catalysts are most active and establishing the relative impact of improved impregnation on conversion and product distributions obtained from coal hydrogenation.

  8. Analysis of volcanic activity patterns using MODIS thermal alerts

    Rothery, Dave A.; Coppola, Diego; Saunders, Charlotte

    2005-01-01

    We investigate eruptive activity by analysis of thermal-alert data from the MODIS (Moderate Resolution Imaging Spectrometer) thermal infrared satellite instrument, detected by the MODVOLC (MODIS Volcano alert) algorithm. These data are openly available on a website, and easy to use. We show how such data can plug major gaps in the conventional monitoring record of volcanoes in an otherwise generally poorly-documented region (Melanesia), including: characterising the mechanism of lava effusion...

  9. Activity Patterns in Latissimus Dorsi and Sternocleidomastoid in Classical Singers

    Watson, Alan H.D.; Williams, Caitlin; James, Buddug V.

    2012-01-01

    Summary Objectives The aim of this study was to investigate and compare the roles of the accessory respiratory muscles, latissimus dorsi (LD), and sternocleidomastoid, in classical singing. Methods Electromyography was used to record the activity of these muscles in six classically trained female singers carrying out a number of singing and nonsinging tasks. Movements of the chest and abdominal walls were monitored simultaneously using inductive plethysmography, and the sound of the phonation...

  10. Exergy Analysis of Human Respiration Under Physical Activity

    Albuquerque Neto, Cyro; Pellegrini, Luiz Felipe; Ferreira, Maurício Silva; DE OLIVEIRA JR., SILVIO; Yanagihara, Jurandir Itizo

    2010-01-01

    This paper presents an exergy analysis of the human body under physical activity. A model of the respiratory system and a model of the thermal system were used for this purpose. These models consider heat and mass transfers in lungs, tissues and blood. Each component of these models is represented by a uniform compartment governed by equations for diffusion, convection, O2 consumption, CO2/heat generation and heat and mass transfer with the environment. The models allow the calculation of the...

  11. Active and thermal imaging performance under bad weather conditions

    Bernard, Erwan; Rivière, Nicolas; Renaudat, Mathieu; Pealat, Michel; Zenou, Emmanuel

    2014-01-01

    Thermal imaging cameras are widely used in military contexts for their night vision capabilities and their observation range; there are based on passive infrared sensors (e.g. MWIR or LWIR range). Under bad weather conditions or when the target is partially hidden (e.g. foliage, military camouflage) they are more and more complemented by active imaging systems, a key technology to perform target identification at long range. The 2D flash imaging technique is based on a high powered pulsed las...

  12. A specific metabolic pattern related to the hallucinatory activity in schizophrenia

    A clinical and PEI study using 18F- fluorodesoxyglucose for measuring local cerebral glucose metabolism with the aim of showing a specific pattern related to the hallucinatory activity, is presented in schizophrenic patients all experiencing hallucinations or pseudo-halluccinations

  13. Using visual information analysis to explore complex patterns in the activity of designers

    Cash, Philip; Stanković, Tino; Štorga, Mario

    2014-01-01

    The analysis of complex interlinked datasets poses a significant problem for design researchers. This is addressed by proposing an information visualisation method for analysing patterns of design activity, qualitatively and quantitatively, with respect to time. This method visualises the tempora...

  14. Issues related to a programme of activities under the CDM

    Ellis, J.

    2006-05-15

    Emissions of CO2 from the energy and land-use change and forestry sectors are responsible for the majority of emissions in non-Annex I Parties to the UNFCCC. Tackling greenhouse gas (GHG) emissions from these sectors is a key to slowing the growth in GHG emissions in non-Annex I countries. Implementing Clean Development Mechanism (CDM) projects can help achieve this aim, while also assisting non-Annex I countries to move towards sustainable development and Annex I countries achieve their emission commitments under the Kyoto Protocol. There has been rapid progress in the CDM over the last year - in terms of the number of projects in the pipeline and registered, and in terms of credits issued. However, some important sectors are notable by their small share in the CDM portfolio. Several countries have also called attention to the need to accelerate the process of approving CDM methodologies and projects. In order to improve the effectiveness of the CDM to achieve its dual objectives, the COP/MOP agreed a decision on 'further guidance relating to the clean development mechanism. This decision lays out guidance on how to improve the operation of the CDM, and includes provisions that allow: (1) Bundling of project activities; and (2) Project activities under a programme of activities, to be registered as a CDM project activity. At present, of the 172 currently registered CDM project activities, 27 involve programmes or bundles. These project activities can include more than one project type, be implemented in several locations, and/or occur in more than one sector. This paper assesses how project activities under a programme of activities under the CDM (referred to here as PCDM) could help to increase the effectiveness of the CDM by encouraging a wide spread of emission mitigation activities. This paper also explores the key issues that may need to be considered for the PCDM concept to be further implemented. The paper concludes that: (1) Key concepts and issues

  15. Pattern of coronary artery disease with no risk factors under age 35 years

    Coronary artery disease (CAD) is no more deemed to be an ailment of the 4 or 5 decade; rather an earlier age incidence is not infrequently encountered in our population. However, there are a few data regarding CAD in young adults, and much about its underlying pathology still remains undetermined. The objective of this study was to delineate the coronary arterial disease pattern in adults under the age of 35 years, but having no known coronary risk factors. Methods: This prospective study was conducted at the Cardiology Departments of all 3 public sector tertiary care hospitals in Peshawar from Jun 2008 to Dec 2009. After having excluded the traditional risk factors for CAD, patients under the age of 35 years with objective evidence of CAD were subjected to percutaneous coronary angiography. Results: Out of a total of 104 patients, 85 (81.73%) patients were men, and 19 (18.27%) were women. The mean age of the whole group was 32.66 +- 3.237 (22-35) years. Significant CAD (>50% diameter narrowing of at least one major coronary artery) was found in 87 (83.7%) patients while 17 (16.3%) patients had non-atherosclerotic coronary artery disease, including 12 (11.53%) patients having normal coronary arteries, 1 (1%) patient had anomalous origin of right coronary artery (RCA), 1 (1%) patient had coronary arteritis, 2 (1.92%) patients had coronary artery ectasia, and 1 (1%) patient had a myocardial bridge over left anterior descending artery (LAD). Among the patients with significant CAD, the prevalence rate of one, two and three vessel disease was 54 (51.9%), 22 (21.2%) and 11 (10.6%) respectively. Almost 50% of the lesions occurred in LAD followed by 25% in RCA and 20% in circumflex, while only one patient (1%) had isolated significant CAD of left main coronary artery. Osteal segments were involved in 10%, proximal in 61%, mid in 21% and distal segments in 7% of the lesions. Conclusion: In the younger age group, CAD is mostly a disease of men, single vessel CAD

  16. Food Patterns According to Sociodemographics, Physical Activity, Sleeping and Obesity in Portuguese Children

    Carla Lopes

    2010-03-01

    Full Text Available Our study aimed to describe the association between food patterns and gender, parental education, physical activity, sleeping and obesity in 1976 children aged 5−10 years old. Dietary intake was measured by a semi quantitative food frequency questionnaire; body mass index was calculated and categorized according to the IOTF classification. Factor analysis and generalized linear models were applied to identify food patterns and their associations. TV viewing and male gender were significant positive predictors for fast-food, sugar sweetened beverages and pastry pattern, while a higher level of maternal education and longer sleeping duration were positively associated with a dietary patterns that included fruit and vegetables.

  17. Objective measurements of daily physical activity patterns and sedentary behaviour in older adults

    Arnardottir, Nanna Yr; Koster, Annemarie; Van Domelen, Dane R; Brychta, Robert J; Caserotti, Paolo; Eiriksdottir, Gudny; Sverrisdottir, Johanna Eyrun; Launer, Lenore J; Gudnason, Vilmundur; Johannsson, Erlingur; Harris, Tamara B; Chen, Kong Y; Sveinsson, Thorarinn

    2013-01-01

    objectively measured population physical activity (PA) data from older persons is lacking. The aim of this study was to describe free-living PA patterns and sedentary behaviours in Icelandic older men and women using accelerometer.......objectively measured population physical activity (PA) data from older persons is lacking. The aim of this study was to describe free-living PA patterns and sedentary behaviours in Icelandic older men and women using accelerometer....

  18. Seasonal activity patterns and diet divergence of three sympatric Afrotropical tortoise species (genus Kinixys)

    Luiselli, Luca

    2003-01-01

    Three species of hinge-back tortoises ( (Kinixys belliana nogueyi, Kinixys erosa, Kinixys homeana) are found in simpatry in the rainforests of the Niger Delta, southern Nigeria (west Africa). The seasonal activity patterns and food habits of these tortoises are studied in the present paper. K. erosa and K. homeana have similar activity patterns, with peaks occurring during the wet season. Kinixys belliana was found only during the wet months. There was no evidence of any specific effect of hu...

  19. Summer movements and activity patterns of river otters in Northeastern Ohio, USA

    David A. Helon; Chris P. Dwyer; Mark D. Witt, et al.

    2013-01-01

    It is important to understand river otter (Lontra canadensis) movement and activity patterns for successful management and reintroduction plans. As part of a river otter study conducted in the Killbuck Watershed, the largest wetland complex in Ohio, USA outside of the Lake Erie marshes, 11 river otters were radio-tagged and monitored for movements and activity patterns. Twenty-seven 24-hour monitoring surveys were conducted during summer months (June-July) of 2002 and 2003. The mean movement ...

  20. Mining Emerging Patterns for Recognizing Activities of Multiple Users in Pervasive Computing

    Gu, Tao; Wu, Zhanqing; Wang, Liang;

    2009-01-01

    sensor readings in a home environment, and propose a novel pattern mining approach to recognize both single-user and multi-user activities in a unified solution. We exploit Emerging Pattern – a type of knowledge pattern that describes significant changes between classes of data – for constructing our......Understanding and recognizing human activities from sensor readings is an important task in pervasive computing. Existing work on activity recognition mainly focuses on recognizing activities for a single user in a smart home environment. However, in real life, there are often multiple inhabitants...... live in such an environment. Recognizing activities of not only a single user, but also multiple users is essential to the development of practical context-aware applications in pervasive computing. In this paper, we investigate the fundamental problem of recognizing activities for multiple users from...

  1. Identifying variably saturated water-flow patterns in a steep hillslope under intermittent heavy rainfall

    El-Kadi, A. I.; Torikai, J.D.

    2001-01-01

    The objective of this paper is to identify water-flow patterns in part of an active landslide, through the use of numerical simulations and data obtained during a field study. The approaches adopted include measuring rainfall events and pore-pressure responses in both saturated and unsaturated soils at the site. To account for soil variability, the Richards equation is solved within deterministic and stochastic frameworks. The deterministic simulations considered average water-retention data, adjusted retention data to account for stones or cobbles, retention functions for a heterogeneous pore structure, and continuous retention functions for preferential flow. The stochastic simulations applied the Monte Carlo approach which considers statistical distribution and autocorrelation of the saturated conductivity and its cross correlation with the retention function. Although none of the models is capable of accurately predicting field measurements, appreciable improvement in accuracy was attained using stochastic, preferential flow, and heterogeneous pore-structure models. For the current study, continuum-flow models provide reasonable accuracy for practical purposes, although they are expected to be less accurate than multi-domain preferential flow models.

  2. Sociocultural patterning of neural activity during self-reflection

    Ma, Yina; Bang, Dan; Wang, Chenbo;

    2014-01-01

    Chinese than in Danish participants. Moreover, the group difference in TPJ activity was mediated by a measure of a cultural value (i.e., interdependence of self-construal). Our findings suggest that individuals in different sociocultural contexts may learn and/or adopt distinct strategies for self......Western cultures encourage self-construals independent of social contexts whereas East Asian cultures foster interdependent self-construals that rely on how others perceive the self. How are culturally specific self-construals mediated by the human brain? Using functional MRI, we monitored neural......-reflection by changing the weight of the mPFC and TPJ in the social brain network....

  3. Aerobic storage under dynamic conditions in activated sludge processes

    Majone, M.; Dircks, K.

    1999-01-01

    In activated sludge processes, several plant configurations (like plug-flow configuration of the aeration tanks, systems with selectors, contact-stabilization processes or SBR processes) impose a concentration gradient of the carbon sources to the biomass. As a consequence, the biomass grows under...... main reference to its relevance on population dynamics in the activated sludge. Possible conceptual approaches to storage modelling are also presented, including both structured and unstructured modelling. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved....... mechanisms can also contribute to substrate removal, depending on the microbial composition and the previous "history" of the biomass. In this paper the type and the extent of this dynamic response is discussed by review of experimental studies on pure cultures, mixed cultures and activated sludges and with...

  4. Physical activity patterns, aerobic fitness and body composition in Norwegian children and adolescents : The Physical Activity among Norwegian Children Study

    Kolle, Elin

    2009-01-01

    Regular physical activity is important for children and adolescent’s healthy growth and for their physical, social and mental health. Therefore, comprehensive knowledge is needed on levels and patterns of physical activity, as well as factors influencing physical activity participation. PURPOSE: The overall purpose was to increase the knowledge regarding 9- and 15-year-olds physical activity level, aerobic fitness and their body composition. Further, to gain increased insight w...

  5. Immature pattern of brain activity in Rett syndrome

    Nielsen, J B; Friberg, L; Lou, H;

    1990-01-01

    Seven girls with Rett syndrome, a progressive degenerative encephalopathy affecting girls, were studied with single photon emission computed tomography and compared with an aged-matched control group of nine normal children. Global cerebral blood flow was significantly lower in Rett syndrome (54 vs...... 69 mL/100 g per minute), and the flows in prefrontal and temporoparietal association regions of the telencephalon were markedly reduced, whereas the primary sensorimotor regions were relatively spared. The flow distribution in Rett syndrome is very similar to the distribution of brain metabolic...... activity in infants of a few months of age. The abnormal regional cerebral blood flow distribution most likely reflects the widespread functional disturbances in the brain of patients with Rett syndrome, whereas computed tomographic and neuropathologic examination only reveal slight changes when compared...

  6. Nonlinear analysis of the change points between A and B phases during the Cyclic Alternating Pattern under normal sleep.

    Chouvarda, I; Mendez, M O; Alba, A; Bianchi, A M; Grassi, A; Arce-Santana, E; Rosso, V; Terzano, M G; Parrino, L

    2012-01-01

    This study analyzes the nonlinear properties of the EEG at transition points of the sequences that build the Cyclic Alternating Pattern (CAP). CAP is a sleep phenomenon built up by consecutive sequences of activations and non-activations observed during the sleep time. The sleep condition can be evaluated from the patterns formed by these sequences. Eleven recordings from healthy and good sleepers were included in this study. We investigated the complexity properties of the signal at the onset and offset of the activations. The results show that EEG signals present significant differences (p<0.05) between activations and non-activations in the Sample Entropy and Tsallis Entropy indices. These indices could be useful in the development of automatic methods for detecting the onset and offset of the activations, leading to significant savings of the physician's time by simplifying the manual inspection task. PMID:23366075

  7. Water supply patterns in two agricultural areas of Central Germany under climate change conditions

    M. H. Tölle

    2012-04-01

    Full Text Available Increasing emissions of greenhouse gases and increasing prices for fossil fuels have highlighted the demand for CO2 "neutral" renewable energy sources, e.g. short rotation forestry systems used for bioenergy. These systems might be vulnerable to changes in temperature, precipitation and occurrence of extreme weather events. To estimate success or failure of such short rotation coppices in a certain area we need regional climate projections and risk assessment. Changes of water supply patterns in two agriculturally extensively used regions in Central Germany (around Göttingen and Großfahner with different climate conditions but both in the temperate climate zone are explored. The study is carried out under present conditions as well as under projected climate change conditions (1971–2100 using A1B and B1 climate scenarios downscaled for Europe. Analysis of precipitation bias shows regional differences: a strong bias in Göttingen area and a weaker bias in the Großfahner area. A bias correction approach, Quantile mapping, is applied to the ensemble results for both areas for winter and summer seasons. By using quantile regression on the seasonal Standardized Precipitation Indices (SPIs as indicator for water supply conditions we found that precipitation is expected to increase in winter in all quantiles of the distribution for Göttingen area during the 21th century. Heavy precipitation is also expected to increase for Großfahner area suggesting a trend to wetter extremes in winter for the future. This winter precipitation increase could trigger runoff and soil erosion risk enhancing the severity of floods. Increasing winter availability of water could enhance local water supply in spring. For both areas no significant change in summer was found over the whole time period. Although the climate change signal of the SPI indicate mild dryer conditions in summer at the end of the 21st century which may trigger water shortage and

  8. Size effects on the wave propagation and deformation pattern in copper nanobars under symmetric longitudinal impact loading

    Molecular dynamics simulations were performed to study the influence of system size on wave propagation and deformation patterns in 〈100〉/{100} copper nanobars with square cross-section under symmetric longitudinal impact loading. Nanobars of longitudinal length 100a with cross-sectional edge lengths h = 10a, 20a, and 40a were impacted on both ends by flyers of size 20a × h × h, where a is the Cu unit cell length, and impact speed 500 m s-1. For reference, quasi-infinite slab samples with periodic cross-sectional edge lengths 10a and 40a were also studied. It was found that the wave propagation speed increases with increasing cross-sectional area and eventually approaches the value obtained for a quasi-infinite sample. Extensive plasticity occurs across the entire length of the nanobars, whereas the quasi-infinite samples remain in the elastic regime and exhibit a vibrating (ringing) behaviour. The deformation pattern in the nanobars is strongly dependent on the cross-sectional area. For the nanobar with h = 10a the material fully reorients from 〈100〉/{100} to 〈110〉/{111} with few stacking faults and twins. Material in the nanobar with h = 20a does not reorient completely; the local crystal deformation is mediated mainly by a partial dislocation activity leading to predominantly non-intersecting stacking faults and twins. Nanobars with h = 40a exhibit behaviour similar to that for the h = 20a case but with greater propensity for intersecting stacking faults.

  9. Chronic osteomyelitis: bone and gallium scan patterns associated with active disease

    Bone and gallium scans are used to assess osteomyelitis patients with prior bone disease. To refine the criteria for interpreting these scans, the data from 136 consecutive patients with clinically suspected osteomyelitis were reviewed. Active osteomyelitis was diagnosed with surgery or biopsy and culture in 49 patients, excluded with the same criteria in 16, and excluded by clinical follow-up for at least 6 months in 71. Five different scintigraphic patterns were found. The true-positive and false-positive ratios, the likelihood ratios, and posterior probabilities for active osteomyelitis in each pattern were calculated. Only one pattern (gallium uptake exceeding bone-seeking radiopharmaceutical uptake) was indicative of active disease. Other patterns slightly raised or decreased the probability of disease. The extent of these changes varies directly with the prior probability of disease, determined from patient-specific factors (e.g., clinical data, laboratory data, findings on plain films) known best by the referring clinician

  10. Peak-valley-peak pattern of histone modifications delineates active regulatory elements and their directionality.

    Pundhir, Sachin; Bagger, Frederik O; Lauridsen, Felicia B; Rapin, Nicolas; Porse, Bo T

    2016-05-19

    Formation of nucleosome free region (NFR) accompanied by specific histone modifications at flanking nucleosomes is an important prerequisite for enhancer and promoter activity. Due to this process, active regulatory elements often exhibit a distinct shape of histone signal in the form of a peak-valley-peak (PVP) pattern. However, different features of PVP patterns and their robustness in predicting active regulatory elements have never been systematically analyzed. Here, we present PARE, a novel computational method that systematically analyzes the H3K4me1 or H3K4me3 PVP patterns to predict NFRs. We show that NFRs predicted by H3K4me1 and me3 patterns are associated with active enhancers and promoters, respectively. Furthermore, asymmetry in the height of peaks flanking the central valley can predict the directionality of stable transcription at promoters. Using PARE on ChIP-seq histone modifications from four ENCODE cell lines and four hematopoietic differentiation stages, we identified several enhancers whose regulatory activity is stage specific and correlates positively with the expression of proximal genes in a particular stage. In conclusion, our results demonstrate that PVP patterns delineate both the histone modification landscape and the transcriptional activities governed by active enhancers and promoters, and therefore can be used for their prediction. PARE is freely available at http://servers.binf.ku.dk/pare. PMID:27095194

  11. A Pattern Mining Approach to Sensor-based Human Activity Recognition

    Gu, Tao; Wang, Liang; Wu, Zhanqing;

    2011-01-01

    Recognizing human activities from sensor readings has recently attracted much research interest in pervasive computing due to its potential in many applications such as assistive living and healthcare. This task is particularly challenging because human activities are often performed in not only a...... real life because activities can be interleaved and performed concurrently in many different ways. In this paper, we propose a novel pattern mining approach to recognize sequential, interleaved and concurrent activities in a unified framework. We exploit Emerging Pattern—a discriminative pattern that...... describes significant changes between classes of data—to identify sensor features for classifying activities. Different from existing learning-based approaches which require different training datasets for building activity models, our activity models are built upon the sequential activity trace only and...

  12. Muscle activation patterns when passively stretching spastic lower limb muscles of children with cerebral palsy.

    Lynn Bar-On

    Full Text Available The definition of spasticity as a velocity-dependent activation of the tonic stretch reflex during a stretch to a passive muscle is the most widely accepted. However, other mechanisms are also thought to contribute to pathological muscle activity and, in patients post-stroke and spinal cord injury can result in different activation patterns. In the lower-limbs of children with spastic cerebral palsy (CP these distinct activation patterns have not yet been thoroughly explored. The aim of the study was to apply an instrumented assessment to quantify different muscle activation patterns in four lower-limb muscles of children with CP. Fifty-four children with CP were included (males/females n = 35/19; 10.8 ± 3.8 yrs; bilateral/unilateral involvement n =  32/22; Gross Motor Functional Classification Score I-IV of whom ten were retested to evaluate intra-rater reliability. With the subject relaxed, single-joint, sagittal-plane movements of the hip, knee, and ankle were performed to stretch the lower-limb muscles at three increasing velocities. Muscle activity and joint motion were synchronously recorded using inertial sensors and electromyography (EMG from the adductors, medial hamstrings, rectus femoris, and gastrocnemius. Muscles were visually categorised into activation patterns using average, normalized root mean square EMG (RMS-EMG compared across increasing position zones and velocities. Based on the visual categorisation, quantitative parameters were defined using stretch-reflex thresholds and normalized RMS-EMG. These parameters were compared between muscles with different activation patterns. All patterns were dominated by high velocity-dependent muscle activation, but in more than half, low velocity-dependent activation was also observed. Muscle activation patterns were found to be both muscle- and subject-specific (p<0.01. The intra-rater reliability of all quantitative parameters was moderate to good. Comparing RMS-EMG between

  13. Summary reports of activities under visiting research program, 1995

    This report contains summary reports of activities under visiting research program, 1995 carried out in the Research Reactor Institute, Kyoto University in 1995. As cooperative activities of KUR, 9 projects and 91 ordinary researches are described in their summaries, with 10 ordinary researches in KUCA cooperative activities. Titles of the 9 projects are development of biological effect analysis of monochromatic neutron spectrum field, study on optimization of bottle condition in ultra cold neutron fission experiment, feature improvement of KUR-ISOL and nuclear spectroscopy and nuclear physics using it, fundamental study on development of new compound for thermal neutron trapping therapy and expansion of its adopting illness, study on properties of synthetic metal using nuclear procedure, neutron diffraction of magnetic substances under the extreme conditions (high pressure, high magnetic field), study on movement in environment of harmful substances, fundamental study on radiation protection against controllable radiation in KUR, and dynamic property study of metal materials using low speed neutron scattering method. (G.K.)

  14. Activity patterns of terrestrial gamebirds in the Willem Pretorius Game reserve, Orange Free State

    C. W. Jubelius; O. B. Kok

    1985-01-01

    Activity patterns of the Natal francolin (Francolinus natalensis), Swaison’s francolin (F. swaisoni) and the crowned guinea-fowl (Numida meleagris) appear to be influenced mainly by climatic conditions, either directly or indirectly. Diurnal activities are characterised by early-morning and late-afternoon peaks and long periods of rest during the middle of the day. Feeding is the most important activity of the birds, followed by maintenance and strenuous activities. Seasonal and species-speci...

  15. LEISURE ACTIVITY PATTERNS AND THEIR ASSOCIATIONS WITH OVERWEIGHT: A PROSPECTIVE STUDY AMONG ADOLESCENTS

    Lajunen, Hanna-Reetta; Keski-Rahkonen, Anna; Pulkkinen, Lea; Rose, Richard J.; Rissanen, Aila; Kaprio, Jaakko

    2009-01-01

    We examined longitudinal associations between individual leisure activities (television viewing, video viewing, computer games, listening to music, board games, musical instrument playing, reading, arts, crafts, socializing, clubs or scouts, sports, outdoor activities) and being overweight using logistic regression and latent class analysis in a cohort of Finnish twins responding to self-report questionnaires at 11–12 (N=5184), 14, and 17 years. We also studied activity patterns (“Active and ...

  16. Pattern of physical activity among persons with type 2 diabetes with special consideration to daily routine

    Arshad, Rozina; Younis, Bilal Bin; Masood, Junaid; Tahira, Maham; Khurhsid, Saima

    2016-01-01

    Objective: Physical activity is essential in maintaining a healthy lifestyle. Physical activity can improve general health, quality of life and diabetes management. The aim and objective of the study was to assess the physical activity trends in daily routine of people with type 2 diabetes. Methods: Two hundred persons with diabetes from four different clinical settings were included to access the trends of physical activity using a customized questionnaire EPIC-2. Pattern of physical activit...

  17. The comparition of Personality Patterns, irrational beliefs and impulsivity in males with with drug abuse disorder under Treatment

    samere asadi; Majid Mahmod allilo; jafar bahadorikhosroahhi; maryam KHORSAND

    2015-01-01

    Objective: the aim of this research was to determine the difference between personality Patterns, irrational beliefs and impulsivity in men with drug abuse disorder under Treatment. Method: in this casual- comparative research, 80 men ( 40 males with drug abuse under Treatment and 40 of normal males) that were selected with available sampling .Groups were matched in terms of demoghraphy characteristics ( age, sexuality, education level and marital status) and were valued with means of Eysenk ...

  18. Dynamics of firing patterns, synchronization and resonances in neuronal electrical activities: experiments and analysis

    Qishao Lu; Huaguang Gu; Zhuoqin Yang; Xia Shi; Lixia Duan; Yanhong Zheng

    2008-01-01

    Recent advances in the experimental and theore-tical study of dynamics of neuronal electrical firing activi-ties are reviewed. Firstly, some experimental phenomena of neuronal irregular firing patterns, especially chaotic and sto-chastic firing patterns, are presented, and practical nonlinear time analysis methods are introduced to distinguish deter-ministic and stochastic mechanism in time series. Secondly, the dynamics of electrical firing activities in a single neu-ron is concerned, namely, fast-slow dynamics analysis for classification and mechanism of various bursting patterns, one- or two-parameter bifurcation analysis for transitions of firing patterns, and stochastic dynamics of firing activities (stochastic and coherence resonances, integer multiple and other firing patterns induced by noise, etc.). Thirdly, different types of synchronization of coupled neurons with electri-cal and chemical synapses are discussed. As noise and time delay are inevitable in nervous systems, it is found that noise and time delay may induce or enhance synchronization and change firing patterns of coupled neurons. Noise-induced resonance and spatiotemporal patterns in coupled neuronal networks are also demonstrated. Finally, some prospects are presented for future research. In consequence, the idea and methods of nonlinear dynamics are of great significance in exploration of dynamic processes and physiological func-tions of nervous systems.

  19. Foraging Activity Pattern Is Shaped by Water Loss Rates in a Diurnal Desert Rodent.

    Levy, Ofir; Dayan, Tamar; Porter, Warren P; Kronfeld-Schor, Noga

    2016-08-01

    Although animals fine-tune their activity to avoid excess heat, we still lack a mechanistic understanding of such behaviors. As the global climate changes, such understanding is particularly important for projecting shifts in the activity patterns of populations and communities. We studied how foraging decisions vary with biotic and abiotic pressures. By tracking the foraging behavior of diurnal desert spiny mice in their natural habitat and estimating the energy and water costs and benefits of foraging, we asked how risk management and thermoregulatory requirements affect foraging decisions. We found that water requirements had the strongest effect on the observed foraging decisions. In their arid environment, mice often lose water while foraging for seeds and cease foraging even at high energetic returns when water loss is high. Mice also foraged more often when energy expenditure was high and for longer times under high seed densities and low predation risks. Gaining insight into both energy and water balance will be crucial to understanding the forces exerted by changing climatic conditions on animal energetics, behavior, and ecology. PMID:27420785

  20. Spike Pattern Structure Influences Synaptic Efficacy Variability under STDP and Synaptic Homeostasis. II: Spike Shuffling Methods on LIF Networks.

    Bi, Zedong; Zhou, Changsong

    2016-01-01

    Synapses may undergo variable changes during plasticity because of the variability of spike patterns such as temporal stochasticity and spatial randomness. Here, we call the variability of synaptic weight changes during plasticity to be efficacy variability. In this paper, we investigate how four aspects of spike pattern statistics (i.e., synchronous firing, burstiness/regularity, heterogeneity of rates and heterogeneity of cross-correlations) influence the efficacy variability under pair-wise additive spike-timing dependent plasticity (STDP) and synaptic homeostasis (the mean strength of plastic synapses into a neuron is bounded), by implementing spike shuffling methods onto spike patterns self-organized by a network of excitatory and inhibitory leaky integrate-and-fire (LIF) neurons. With the increase of the decay time scale of the inhibitory synaptic currents, the LIF network undergoes a transition from asynchronous state to weak synchronous state and then to synchronous bursting state. We first shuffle these spike patterns using a variety of methods, each designed to evidently change a specific pattern statistics; and then investigate the change of efficacy variability of the synapses under STDP and synaptic homeostasis, when the neurons in the network fire according to the spike patterns before and after being treated by a shuffling method. In this way, we can understand how the change of pattern statistics may cause the change of efficacy variability. Our results are consistent with those of our previous study which implements spike-generating models on converging motifs. We also find that burstiness/regularity is important to determine the efficacy variability under asynchronous states, while heterogeneity of cross-correlations is the main factor to cause efficacy variability when the network moves into synchronous bursting states (the states observed in epilepsy). PMID:27555816

  1. Damage pattern and damage progression on breakwater roundheads under multidirectional waves

    Comola, F.; Andersen, Thomas Lykke; Martinelli, L.;

    2014-01-01

    An experimental model test study is carried out to investigate damage pattern and progression on a rock armoured breakwater roundhead subjected to multidirectional waves. Concerning damage pattern, the most critical sector is observed to shift leeward with increasing wave period. Taking angles...... characteristics. The damage progression is observed dependent on significant wave height and peak wave period, but not on the directional spreading and the spectral width of the incident waves. Combining the results of both damage pattern and damage progression, a stability formula for the distribution of damage...

  2. Size-resolved particle number emission patterns under real-world driving conditions using positive matrix factorization

    Domínguez-Sáez, A.; Viana, M.; Barrios, C.C.; Rubio, J.R.; Amato, F.; Pujadas, M.; Querol, X.

    2012-01-01

    A novel on-board system was tested to characterize size-resolved particle number emission patterns under real-world driving conditions, running in a EURO4 diesel vehicle and in a typical urban circuit in Madrid (Spain). Emission profiles were determined as a function of driving conditions. Source ap

  3. Implications of climatic seasonality on activity patterns and resource use by sympatric peccaries in northern Pantanal

    Hofmann, Gabriel Selbach; Coelho, Igor Pfeifer; Bastazini, Vinicius Augusto Galvão; Cordeiro, José Luís Passos; de Oliveira, Luiz Flamarion Barbosa

    2016-03-01

    We evaluated the effects of climate seasonality from a thermal and water availability perspective on the activity patterns and resource use of Pecari tajacu and Tayassu pecari during wet and dry seasons in the northeastern Brazilian Pantanal. We used camera traps and temperature sensors to record species activity patterns in relation to temperature, established five habitat categories based on flooding intensity and local vegetation characteristics, assessed the activity patterns of each species in dry and wet periods and in artificial water bodies using circular statistical metrics, and calculated niche amplitude and overlap on three axes (temperature, time, and habitat) in both periods. Peccaries shared a strong resemblance in resource use and in their responses to seasonal variations in the tested gradients. The activity patterns of both species exhibited a significant correlation with air temperature on all the evaluated measures, and both species strongly reduced their activity when the air temperature exceeded 35 °C. High temperatures associated with low water availability were most likely responsible for the changes in species activity patterns, which resulted in an increased temporal overlap in habitat use throughout the dry season. However, the peccaries avoided intensively flooded habitats; therefore, the habitat gradient overlap was greater during the wet period. Our results show that an increase in niche overlap on the environmental gradient as a result of climatic seasonality may be partially compensated by a reduction in other niche dimensions. In this case, temporal partitioning appears to be an important, viable mechanism to reduce competition by potentially competing species.

  4. Patterns of regional brain activation associated with different forms of motor learning.

    Ghilardi, M; Ghez, C; Dhawan, V; Moeller, J; Mentis, M; Nakamura, T; Antonini, A; Eidelberg, D

    2000-07-14

    To examine the variations in regional cerebral blood flow during execution and learning of reaching movements, we employed a family of kinematically and dynamically controlled motor tasks in which cognitive, mnemonic and executive features of performance were differentiated and characterized quantitatively. During 15O-labeled water positron emission tomography (PET) scans, twelve right-handed subjects moved their dominant hand on a digitizing tablet from a central location to equidistant targets displayed with a cursor on a computer screen in synchrony with a tone. In the preceding week, all subjects practiced three motor tasks: 1) movements to a predictable sequence of targets; 2) learning of new visuomotor transformations in which screen cursor motion was rotated by 30 degrees -60 degrees; 3) learning new target sequences by trial and error, by using previously acquired routines in a task placing heavy load on spatial working memory. The control condition was observing screen and audio displays. Subtraction images were analyzed with Statistical Parametric Mapping to identify significant brain activation foci. Execution of predictable sequences was characterized by a modest decrease in movement time and spatial error. The underlying pattern of activation involved primary motor and sensory areas, cerebellum, basal ganglia. Adaptation to a rotated reference frame, a form of procedural learning, was associated with decrease in the imposed directional bias. This task was associated with activation in the right posterior parietal cortex. New sequences were learned explicitly. Significant activation was found in dorsolateral prefrontal and anterior cingulate cortices. In this study, we have introduced a series of flexible motor tasks with similar kinematic characteristics and different spatial attributes. These tasks can be used to assess specific aspects of motor learning with imaging in health and disease. PMID:10882792

  5. Longitudinal variability of time-location/activity patterns of population at different ages: a longitudinal study in California

    Cassady Diana L

    2011-09-01

    Full Text Available Abstract Background Longitudinal time-activity data are important for exposure modeling, since the extent to which short-term time-activity data represent long-term activity patterns is not well understood. This study was designed to evaluate longitudinal variations in human time-activity patterns. Method We report on 24-hour recall diaries and questionnaires collected via the internet from 151 parents of young children (mostly under age 55, and from 55 older adults of ages 55 and older, for both a weekday and a weekend day every three months over an 18-month period. Parents also provided data for their children. The self-administrated diary and questionnaire distinguished ~30 frequently visited microenvironments and ~20 activities which we selected to represent opportunities for exposure to toxic environmental compounds. Due to the non-normal distribution of time-location/activity data, we employed generalized linear mixed-distribution mixed-effect models to examine intra- and inter-individual variations. Here we describe variation in the likelihood of and time spent engaging in an activity or being in a microenvironment by age group, day-type (weekday/weekend, season (warm/cool, sex, employment status, and over the follow-up period. Results As expected, day-type and season influence time spent in many location and activity categories. Longitudinal changes were also observed, e.g., young children slept less with increasing follow-up, transit time increased, and time spent on working and shopping decreased during the study, possibly related to human physiological changes with age and changes in macro-economic factors such as gas prices and the economic recession. Conclusions This study provides valuable new information about time-activity assessed longitudinally in three major age groups and greatly expands our knowledge about intra- and inter-individual variations in time-location/activity patterns. Longitudinal variations beyond weekly and

  6. Comparing Activity Patterns, Biological, and Family Factors in Children with and without Developmental Coordination Disorder

    Beutum, Monique Natalie; Cordier, Reinie; Bundy, Anita

    2013-01-01

    The association between motor proficiency and moderate to vigorous physical activity (MVPA) suggests children with developmental coordination disorder (DCD) may be susceptible to inactivity-related conditions such as cardiovascular diseases. The aim of this study was to compare children with and without DCD on physical activity patterns, activity…

  7. Motives for Using Facebook, Patterns of Facebook Activities, and Late Adolescents' Social Adjustment to College

    Yang, Chia-chen; Brown, B. Bradford

    2013-01-01

    Previous studies have confirmed that Facebook, the leading social networking site among young people, facilitates social connections among college students, but the specific activities and motives that foster social adjustment remain unclear. This study examined associations between patterns of Facebook activity, motives for using Facebook, and…

  8. Twenty-four hour activity budgets and patterns of behavior in captive ocelots (Leopardus pardalis).

    Weller, S H.; Bennett, C L.

    2001-02-16

    Activity budgets of captive ocelots (Leopardus pardalis) were assessed from over 547h of observational data obtained from six ocelots; two females at the Dallas Zoo (Dallas, TX), two females at the Caldwell Zoo (Tyler, TX) and a male and female at the Fossil Rim Wildlife Center (Glen Rose, TX). Data were examined for the percentage of active behaviors exhibited during the day and nighttime hours; temporal patterns of active, pace, exploratory and marking behavior, and for significance in pacing behavior between pre- and post-feeding times. The captive cats had a bimodal pattern of active behavior similar to field studies of wild ocelots, except that the timing of the active peaks were closer to the diurnal hours for the captive cats. The captive ocelots were less active than wild ocelots, and more diurnal. Also, the captive cats exhibited stereotypic pacing. When the percentage of time of active behavior was assessed for each cat, a strong variation between individuals and institution was not seen. Pacing behavior was highest prior to the feeding times for the cats. In assessing patterns of behavior, peaks in marking and exploratory behavior in the cats did not occur at the same time as the peaks in active behavior. However, we did see institutional differences in the pattern of exploratory and marking behavior, which may have been influenced by differing management practices. PMID:11179560

  9. The activity pattern of shoulder muscles in subjects with and without subacromial impingement

    Diederichsen, Louise Pyndt; Nørregaard, Jesper; Dyhre-Poulsen, Poul; Winther, Annika; Tufekovic, Goran; Bandholm, Thomas; Rasmussen, Lars Raundal; Krogsgaard, Michael

    2009-01-01

    Altered shoulder muscle activity is frequently believed to be a pathogenetic factor of subacromial impingement (SI) and therapeutic interventions have been directed towards restoring normal motor patterns. Still, there is a lack of scientific evidence regarding the changes in muscle activity in p...

  10. Patterns of Attendance of Children Under 12 Years at School Dental Service in Western Australia

    Lam, SPL; Baros, H; O’Grady, MJ; Kendall, GE; Messer, LB; Slack-Smith, LM

    2012-01-01

    The aim of this study was to investigate the patterns of attendance at School Dental Service (SDS) and reasons for attendance (treatment or prevention) for children in the Perth Metropolitan Area, in particular investigating the first year of SDS attendance and attendance until the year the child turned 12. The first 150 SDS records located for children from the Western Australian Pregnancy Cohort (Raine) Study were used for this study. Patterns of attendance of children at SDS were described...

  11. Mining frequent patterns for AMP-activated protein kinase regulation on skeletal muscle

    Chen Yi-Ping

    2006-08-01

    Full Text Available Abstract Background AMP-activated protein kinase (AMPK has emerged as a significant signaling intermediary that regulates metabolisms in response to energy demand and supply. An investigation into the degree of activation and deactivation of AMPK subunits under exercise can provide valuable data for understanding AMPK. In particular, the effect of AMPK on muscle cellular energy status makes this protein a promising pharmacological target for disease treatment. As more AMPK regulation data are accumulated, data mining techniques can play an important role in identifying frequent patterns in the data. Association rule mining, which is commonly used in market basket analysis, can be applied to AMPK regulation. Results This paper proposes a framework that can identify the potential correlation, either between the state of isoforms of α, β and γ subunits of AMPK, or between stimulus factors and the state of isoforms. Our approach is to apply item constraints in the closed interpretation to the itemset generation so that a threshold is specified in terms of the amount of results, rather than a fixed threshold value for all itemsets of all sizes. The derived rules from experiments are roughly analyzed. It is found that most of the extracted association rules have biological meaning and some of them were previously unknown. They indicate direction for further research. Conclusion Our findings indicate that AMPK has a great impact on most metabolic actions that are related to energy demand and supply. Those actions are adjusted via its subunit isoforms under specific physical training. Thus, there are strong co-relationships between AMPK subunit isoforms and exercises. Furthermore, the subunit isoforms are correlated with each other in some cases. The methods developed here could be used when predicting these essential relationships and enable an understanding of the functions and metabolic pathways regarding AMPK.

  12. Extraction and characterization of essential discharge patterns from multisite recordings of spiking ongoing activity.

    Riccardo Storchi

    Full Text Available BACKGROUND: Neural activation patterns proceed often by schemes or motifs distributed across the involved cortical networks. As neurons are correlated, the estimate of all possible dependencies quickly goes out of control. The complex nesting of different oscillation frequencies and their high non-stationariety further hamper any quantitative evaluation of spiking network activities. The problem is exacerbated by the intrinsic variability of neural patterns. METHODOLOGY/PRINCIPAL FINDINGS: Our technique introduces two important novelties and enables to insulate essential patterns on larger sets of spiking neurons and brain activity regimes. First, the sampling procedure over N units is based on a fixed spike number k in order to detect N-dimensional arrays (k-sequences, whose sum over all dimension is k. Then k-sequences variability is greatly reduced by a hierarchical separative clustering, that assigns large amounts of distinct k-sequences to few classes. Iterative separations are stopped when the dimension of each cluster comes to be smaller than a certain threshold. As threshold tuning critically impacts on the number of classes extracted, we developed an effective cost criterion to select the shortest possible description of our dataset. Finally we described three indexes (C,S,R to evaluate the average pattern complexity, the structure of essential classes and their stability in time. CONCLUSIONS/SIGNIFICANCE: We validated this algorithm with four kinds of surrogated activity, ranging from random to very regular patterned. Then we characterized a selection of ongoing activity recordings. By the S index we identified unstable, moderatly and strongly stable patterns while by the C and the R indices we evidenced their non-random structure. Our algorithm seems able to extract interesting and non-trivial spatial dynamics from multisource neuronal recordings of ongoing and potentially stimulated activity. Combined with time-frequency analysis of

  13. Catalyst dispersion and activity under conditions of temperature- staged liquefaction

    Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

    1991-09-01

    The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experimental program will focus upon the development of effective methods of impregnating coal with catalysts, evaluating the conditions under which the catalysts are most active and establishing the relative impact of improved impregnation on conversion and product distributions obtained from coal hydrogenation. Liquefaction experiments of solvent-treated and untreated Blind Canyon (DECS-6) and Texas lignite (DECS-1) have been performed using ammonium tetrathiomolybdate (ATTM) and bis (dicarbonylcyclopentadienyl) iron (CPI) as catalyst precursors using temperature-staged conditions (275{degrees}C, 30 min; 425{degrees}C, 30 min). Solid state {sup 13}C NMR analysis was carried out for each coal and for selected residues. 12 refs., 14 figs., 9 tabs.

  14. Hippocampal CA2 activity patterns change over time to a larger extent than between spatial contexts.

    Mankin, Emily A; Diehl, Geoffrey W; Sparks, Fraser T; Leutgeb, Stefan; Leutgeb, Jill K

    2015-01-01

    The hippocampal CA2 subregion has a different anatomical connectivity pattern within the entorhino-hippocampal circuit than either the CA1 or CA3 subregion. Yet major differences in the neuronal activity patterns of CA2 compared with the other CA subregions have not been reported. We show that standard spatial and temporal firing patterns of individual hippocampal principal neurons in behaving rats, such as place fields, theta modulation, and phase precession, are also present in CA2, but that the CA2 subregion differs substantially from the other CA subregions in its population coding. CA2 ensembles do not show a persistent code for space or for differences in context. Rather, CA2 activity patterns become progressively dissimilar over time periods of hours to days. The weak coding for a particular context is consistent with recent behavioral evidence that CA2 circuits preferentially support social, emotional, and temporal rather than spatial aspects of memory. PMID:25569350

  15. Relationship between BOLD amplitude and pattern classification of orientation-selective activity in the human visual cortex

    Tong, Frank; Harrison, Stephenie A.; Dewey, John A.; Kamitani, Yukiyasu

    2012-01-01

    Orientation-selective responses can be decoded from fMRI activity patterns in the human visual cortex, using multivariate pattern analysis (MVPA). To what extent do these feature-selective activity patterns depend on the strength and quality of the sensory input, and might the reliability of these activity patterns be predicted by the gross amplitude of the stimulus-driven BOLD response? Observers viewed oriented gratings that varied in luminance contrast (4, 20 or 100%) or spatial frequency ...

  16. Pattern, Growth and Aging in a Colony of Clustering Active Swimmers

    Das, Subir K.

    2016-01-01

    Via molecular dynamics simulations, we study the kinetics in a phase separating active matter model. Quantitative results for the isotropic bicontinuous pattern formation, its growth and aging, studied, respectively, via the two-point equal-time density-density correlation function, the average domain length and the two-time density autocorrelation function, are presented. Both the correlation functions exhibit basic scaling properties, implying self-similarity in the pattern dynamics, for wh...

  17. Food Patterns According to Sociodemographics, Physical Activity, Sleeping and Obesity in Portuguese Children

    Carla Lopes; André Moreira; Vanessa Mitchell; Vitor Teixeira; Renata Barros; Hugo Valente; Mariana Bessa; Tânia Cordeiro; Patrícia Padrão; Susana Santos; Pedro Moreira

    2010-01-01

    Our study aimed to describe the association between food patterns and gender, parental education, physical activity, sleeping and obesity in 1976 children aged 5−10 years old. Dietary intake was measured by a semi quantitative food frequency questionnaire; body mass index was calculated and categorized according to the IOTF classification. Factor analysis and generalized linear models were applied to identify food patterns and their associations. TV viewing and male gender were significant po...

  18. Seasonal variation in daily activity patterns of free-ranging European ground squirrels (Spermophilus citellus).

    Everts, Lammina G; Strijkstra, Arjen M; Hut, Roelof A; Hoffmann, Ilse E; Millesi, Eva

    2004-01-01

    Daily aboveground activity of European ground squirrels (Spermophilus citellus) in their natural habitat was recorded with a visual scanning procedure during the active seasons of 1992 and 1993. Activity patterns were analyzed with respect to time of year and to the animal's reproductive state. Aboveground activity started on average 3.9 h (SD 0.6 h, n = 37 days) after civil twilight at dawn and ended on average 3.2 h (SD 0.9 h, n = 37 days) before civil twilight at dusk. Between onset and offset of activity, 54% was spent aboveground, of which 73% was spent foraging. Activity patterns were influenced by photoperiod, rainfall, and by reproductive state. During mating, reproductively active males started activity earlier than females and reproductively inactive males. For females, time spent foraging was high during lactation. The midpoint of daily activity was at 12:16 h (SD 0.37 h, n = 37 days). Activity patterns of European ground squirrels thus appear robustly positioned in the middle of the photoperiod. PMID:15129824

  19. Adaptive integration of local region information to detect fine-scale brain activity patterns

    2008-01-01

    With the rapid development of functional magnetic resonance imaging (fMRI) technology, the spatial resolution of fMRI data is continuously growing. This pro- vides us the possibility to detect the fine-scale patterns of brain activities. The es- tablished univariate and multivariate methods to analyze fMRI data mostly focus on detecting the activation blobs without considering the distributed fine-scale pat- terns within the blobs. To improve the sensitivity of the activation detection, in this paper, multivariate statistical method and univariate statistical method are com- bined to discover the fine-grained activity patterns. For one voxel in the brain, a local homogenous region is constructed. Then, time courses from the local ho- mogenous region are integrated with multivariate statistical method. Univariate statistical method is finally used to construct the interests of statistic for that voxel. The approach has explicitly taken into account the structures of both activity pat- terns and existing noise of local brain regions. Therefore, it could highlight the fine-scale activity patterns of the local regions. Experiments with simulated and real fMRI data demonstrate that the proposed method dramatically increases the sensitivity of detection of fine-scale brain activity patterns which contain the subtle information about experimental conditions.

  20. Global feedback control of Turing patterns in network-organized activator-inhibitor systems

    Hata, S.; Nakao, H.; Mikhailov, A. S.

    2012-06-01

    Results of the first systematic study on feedback control of nonequilibrium pattern formation in networks are reported. Effects of global feedback control on Turing patterns in network-organized activator-inhibitor system have been investigated. The feedback signal was introduced into one of the parameters of the system and was proportional to the amplitude of the developing Turing pattern. Without the control, the Turing instability corresponded to a subcritical bifurcation and hysteresis effects were observed. Sufficiently strong feedback control rendered, however, the bifurcation supercritical and eliminated the hysteresis effects.

  1. Soil Enzyme Activities under Agroforestry Systems in Northern Jiangsu Province

    Wan Fuxu; Chen Ping

    2004-01-01

    The authors presented the enzyme characteristics of catalase, sucrase, urease and alkaline phosphatase under agroforestry systems in northern Jiangsu Province. The results show that soil enzyme activities reduce gradually from top to bottom layer of the soil profile, and the fluctuations of catalase and urease are smaller than those of sucrase and alkaline phosphatase. Soil enzyme activities differe significantly in different samples, and the order is arranged as poplar-crop intercropping segment (A, D) > paulownia-crop intercropping segment (B, C) > CK. Furthermore, soil enzyme activities increase with intercropping age. On the other hand, in the same plot, there are closer relationships between enzymes in the soil samples. Catalase, alkaline phosphatase and urease are negatively related, while alkaline phosphatase and urease are positively related (except in samples B and C). In addition, the enzyme activities have a close relationship with the fertilizers. Catalase is positively correlated with the soil pH value (r = 0.854, 0.804, 0.078 and 0.082, respectively), and is negatively correlated with total N (r = -0.201, -0.529, -0.221 and -0.821, respectively), total P (r = -0.143, -0.213, -0.362 and -0.751, respectively) and available P (r = -0.339, -0.351, -0.576, and -0.676, respectively). Sucrase, urease and alkaline phosphatase are negatively correlated with the pH value, while positively correlated with the other fertilizers (r ≈ 1). The authors suggest that enzyme activity will be a great potential as an indicator of soil quality.

  2. Exergy performance of human body under physical activities

    The aim of this work is to apply performance indicators for individuals under physical activity based on the concepts of exergy destroyed and exergy efficiency. The cardiopulmonary exercise test is one of the most used tests to assess the functional capacity of individuals with varying degrees of physical training. To perform the exergy analysis during the test, it is necessary to calculate heat and mass flow rates, associated with radiation, convection, vaporization and respiration, determined from the measurements and some relations found in the literature. The energy balance allowed the determination of the internal temperature over time and the exergy variation of the body along the experiment. Eventually, it was possible to calculate the destroyed exergy and the exergy efficiency from the exergy analysis. The exergy rates and flow rates are dependent of the exercise level and the body metabolism. The results show that the relation between the destroyed exergy and the metabolism is almost constant during the test, furthermore its value has a great dependence of the subject age. From the exergy analysis it was possible to divide the subjects according to their training level, for the same destroyed exergy, subjects with higher lactate threshold can perform more work. - Highlights: • Exergy analysis was applied to the human body under physical activities. • Concept of maximum available work from ATP hydrolysis was compared with exergy analysis results. • For the same destroyed exergy, subjects with higher lactate threshold can perform more work. • Runners during physical activities tend to a state of minimum destroyed exergy and maximum exergy efficiency

  3. Mirrored patterns of lateralized neuronal activation reflect old and new memories in the avian auditory cortex.

    Olson, Elizabeth M; Maeda, Rie K; Gobes, Sharon M H

    2016-08-25

    In monolingual humans, language-related brain activation shows a distinct lateralized pattern, in which the left hemisphere is often dominant. Studies are not as conclusive regarding the localization of the underlying neural substrate for language in sequential language learners. Lateralization of the neural substrate for first and second language depends on a number of factors including proficiency and early experience with each language. Similar to humans learning speech, songbirds learn their vocalizations from a conspecific tutor early in development. Here, we show mirrored patterns of lateralization in the avian analog of the mammalian auditory cortex (the caudomedial nidopallium [NCM]) in sequentially tutored zebra finches (Taeniopygia guttata​) in response to their first tutor song, learned early in development, and their second tutor song, learned later in development. The greater the retention of song from their first tutor, the more right-dominant the birds were when exposed to that song; the more birds learned from their second tutor, the more left-dominant they were when exposed to that song. Thus, the avian auditory cortex may preserve lateralized neuronal traces of old and new tutor song memories, which are dependent on proficiency of song learning. There is striking resemblance in humans: early-formed language representations are maintained in the brain even if exposure to that language is discontinued. The switching of hemispheric dominance related to the acquisition of early auditory memories and subsequent encoding of more recent memories may be an evolutionary adaptation in vocal learners necessary for the behavioral flexibility to acquire novel vocalizations, such as a second language. PMID:27288718

  4. Wet and Dry Tribological Behaviors of Circular Islandic Protrusion Patterns on M2 Steel Discs under Spinning Condition

    Hing-Yin MA; DONG Guangneng; LI Jian; MENG HUA; Chiu-Kam MOK

    2008-01-01

    Under spinning conditions, lubricant on islandic spot patterned M2 steel disc experiences centrifugal and tangential force components. Depending upon the relative position of the spots and the flow of lubricant, accumulation of lubricant in front of patterned islandic spots creates thrusting to mating part and subsequently reduces contact between the mating couple. Whilst wear debris is likely to be spun off the plateau of the spots to their neighbouring valleys so as to reduce wear.Hence, it gives favorable tribological characteristics. Aiming at verifying such mechanisms, studies were performed on M2 steel disc specimens slid with ASSAB 17 tool steel pin. The M2 steel disc specimens were respectively (I) machined with non-patterned (NP), (ii) etched to produce in-lined (INE) islandic patterns, and (iii) etched to produce staggered (STE) islandic spot patterns. Results indicated that the INE patterned discs gave most favorable wear characteristics, the NP of the worse characteristics whilst the STE ranged in the middle. However, the actual contact mechanism leads to the descending sequence of favorable friction behaviors nominally as: NP, INE and STE.

  5. Unsupervised classification of neocortical activity patterns in neonatal and pre-juvenile rodents

    Nicole eCichon

    2014-05-01

    Full Text Available Flexible communication within the brain, which relies on oscillatory activity, is not confined to adult neuronal networks. Experimental evidence has documented the presence of discontinuous patterns of oscillatory activity already during early development. Their highly variable spatial and time-frequency organization has been related to region specificity. However, it might be equally due to the absence of unitary criteria for classifying the early activity patterns, since they have been mainly characterized by visual inspection. Therefore, robust and unbiased methods for categorizing these discontinuous oscillations are needed for increasingly complex data sets from different labs. Here, we introduce an unsupervised detection and classification algorithm for the discontinuous activity patterns of rodents during early development. For this, firstly time windows with discontinuous oscillations vs. epochs of network silence were identified. In a second step, the major features of detected events were identified and processed by principal component analysis for deciding on their contribution to the classification of different oscillatory patterns. Finally, these patterns were categorized using an unsupervised cluster algorithm. The results were validated on manually characterized neonatal spindle bursts, which ubiquitously entrain neocortical areas of rats and mice, and prelimbic nested gamma spindle bursts. Moreover, the algorithm led to satisfactory results for oscillatory events that, due to increased similarity of their features, were more difficult to classify, e.g. during the pre-juvenile developmental period. Based on a linear classification, the optimal number of features to consider increased with the difficulty of detection. This algorithm allows the comparison of neonatal and pre-juvenile oscillatory patterns in their spatial and temporal organization. It might represent a first step for the unbiased elucidation of activity patterns

  6. Unsupervised classification of neocortical activity patterns in neonatal and pre-juvenile rodents.

    Cichon, Nicole B; Denker, Michael; Grün, Sonja; Hanganu-Opatz, Ileana L

    2014-01-01

    Flexible communication within the brain, which relies on oscillatory activity, is not confined to adult neuronal networks. Experimental evidence has documented the presence of discontinuous patterns of oscillatory activity already during early development. Their highly variable spatial and time-frequency organization has been related to region specificity. However, it might be equally due to the absence of unitary criteria for classifying the early activity patterns, since they have been mainly characterized by visual inspection. Therefore, robust and unbiased methods for categorizing these discontinuous oscillations are needed for increasingly complex data sets from different labs. Here, we introduce an unsupervised detection and classification algorithm for the discontinuous activity patterns of rodents during early development. For this, in a first step time windows with discontinuous oscillations vs. epochs of network "silence" were identified. In a second step, the major features of detected events were identified and processed by principal component analysis for deciding on their contribution to the classification of different oscillatory patterns. Finally, these patterns were categorized using an unsupervised cluster algorithm. The results were validated on manually characterized neonatal spindle bursts (SB), which ubiquitously entrain neocortical areas of rats and mice, and prelimbic nested gamma spindle bursts (NG). Moreover, the algorithm led to satisfactory results for oscillatory events that, due to increased similarity of their features, were more difficult to classify, e.g., during the pre-juvenile developmental period. Based on a linear classification, the optimal number of features to consider increased with the difficulty of detection. This algorithm allows the comparison of neonatal and pre-juvenile oscillatory patterns in their spatial and temporal organization. It might represent a first step for the unbiased elucidation of activity patterns

  7. Behavioral daily rhythmic activity pattern of adolescent female rat is modulated by acute and chronic cocaine

    Min J. Lee; Keith D. Burau; Dafny, Nachum

    2013-01-01

    Cocaine is one of well-known drugs of abuse, and many children experience early exposure to cocaine. Because of an immature neuronal system in adolescents, they may react differently to repeated cocaine administration compared to adults. Most of the published papers report the effect of cocaine on adult male rats and this paper focused on the effects of cocaine on the 24 h locomotor activity rhythm patterns activity of adolescent Sprague Dawley (SD) female rats. Changes in the locomotor activ...

  8. Summary reports of activities under visiting research program

    Technical Report of the Research Reactor Institute, Kyoto University, is published any time as a prompt report as occasion requires. In this report, the title, names of reporters and summary of each of 53 researches which were carried out under the visiting research program in the first half of 1983 are given. The titles are, for example, a mechanism for the anodic oxidation of GaAs, gamma-gamma perturbed angular correlation study of relaxation phenomena, the studies on the genesis of volcanic rocks by partition of trace elements, neutron activation analysis of geochemical standard rock samples, studies on the changes of elements in the fur of rats with various disease, neutron activation analysis on glacier ice strata and glaciegla lake sediments in Nepal Himalayas, low temperature irradiation effects on bcc metals, organ and its subcellular distribution of manganese ion in animals, structure analysis of orthorhombic BaTiO3 by profile analysis method, regional distribution of Mn, Zn and Cu in human brain, neutron diffraction study of Mn-Ni alloy, structural change of KCoF3 in the vicinity of the critical region, activation analysis of trace elements in tumor tissues (thyroid) and so on. (Kako, I.)

  9. Sleeping under the Ocean: Despite Total Isolation, Nuclear Submariners Maintain Their Sleep and Wake Patterns throughout Their Under Sea Mission.

    Marion Trousselard

    Full Text Available To assess the effects of isolation, inadequate exposure to light and specific shift work on the subjective and objective measurements of sleep and alertness of submariners.A strictly controlled randomized crossover study with the polysomnography recorded twice during the mission.Setting: Shift and night work with prolonged (70 days social isolation from the real world (with no phone or Internet contact with families or friends during a routine mission aboard the "Téméraire" French Strategic Submarine with Ballistic Nuclear missiles (SSBN. Participants: 19 submariners working on a 24-hour shift for three days in a row schedule. Interventions: The participants attended two polysomnographic (PSG recordings of night sleep on Day 21 (D21 and Day 51 (D51 of the 70-day patrol; urine cortisol levels were also taken after sleep, and subjective assessments of sleep, sleepiness, mood and anxiety on D21 and D51. The light and temperature on board were also recorded.PSG analyses showed that sleep did not significantly vary in length (total sleep time or in quality between D21 and D51. The mariners reported the same subjective sleep, sleepiness, anxiety or mood (except for a slightly worse score for confusion on D51. Blood cortisol levels did not vary significantly.These results show that humans living in an isolated environment for more than two months with this specific shift schedule do not suffer from any significant effects on sleep, sleepiness and confusion between D21 and D51, when they follow an organized regular shift pattern with controlled light and temperature.

  10. Multivoxel Patterns Reveal Functionally Differentiated Networks Underlying Auditory Feedback Processing of Speech

    Zheng, Zane Z.; Vicente-Grabovetsky, Alejandro; MacDonald, Ewen N.;

    2013-01-01

    human participants were vocalizing monosyllabic words, and to present the same auditory stimuli while participants were passively listening. Whole-brain analysis of neural-pattern similarity revealed three functional networks that were differentially sensitive to distorted auditory feedback during...... vocalization, compared with during passive listening. One network of regions appears to encode an “error signal” regardless of acoustic features of the error: this network, including right angular gyrus, right supplementary motor area, and bilateral cerebellum, yielded consistent neural patterns across...... presented as auditory concomitants of vocalization. A third network, showing a distinct functional pattern from the other two, appears to capture aspects of both neural response profiles. Together, our findings suggest that auditory feedback processing during speech motor control may rely on multiple...