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Sample records for cultured neocortical networks

  1. Effect of acute stretch injury on action potential and network activity of rat neocortical neurons in culture.

    Science.gov (United States)

    Magou, George C; Pfister, Bryan J; Berlin, Joshua R

    2015-10-22

    The basis for acute seizures following traumatic brain injury (TBI) remains unclear. Animal models of TBI have revealed acute hyperexcitablility in cortical neurons that could underlie seizure activity, but studying initiating events causing hyperexcitability is difficult in these models. In vitro models of stretch injury with cultured cortical neurons, a surrogate for TBI, allow facile investigation of cellular changes after injury but they have only demonstrated post-injury hypoexcitability. The goal of this study was to determine if neuronal hyperexcitability could be triggered by in vitro stretch injury. Controlled uniaxial stretch injury was delivered to a spatially delimited region of a spontaneously active network of cultured rat cortical neurons, yielding a region of stretch-injured neurons and adjacent regions of non-stretched neurons that did not directly experience stretch injury. Spontaneous electrical activity was measured in non-stretched and stretch-injured neurons, and in control neuronal networks not subjected to stretch injury. Non-stretched neurons in stretch-injured cultures displayed a three-fold increase in action potential firing rate and bursting activity 30-60 min post-injury. Stretch-injured neurons, however, displayed dramatically lower rates of action potential firing and bursting. These results demonstrate that acute hyperexcitability can be observed in non-stretched neurons located in regions adjacent to the site of stretch injury, consistent with reports that seizure activity can arise from regions surrounding the site of localized brain injury. Thus, this in vitro procedure for localized neuronal stretch injury may provide a model to study the earliest cellular changes in neuronal function associated with acute post-traumatic seizures. Copyright © 2015. Published by Elsevier B.V.

  2. The Sub-Regional Functional Organization of Neocortical Irritative Epileptic Networks in Pediatric Epilepsy

    Czech Academy of Sciences Publication Activity Database

    Janča, R.; Kršek, P.; Ježdík, P.; Čmejla, R.; Tomášek, M.; Komárek, V.; Marusič, P.; Jiruška, Přemysl

    2018-01-01

    Roč. 9, Mar 23 (2018), č. článku 184. ISSN 1664-2295 R&D Projects: GA MZd(CZ) NV15-29835A Institutional support: RVO:67985823 Keywords : interictal epileptiform discharges * brain networks * epilepsy surgery * irritative zone * propagation * neocortical epilepsy Subject RIV: FH - Neurology OBOR OECD: Neurosciences (including psychophysiology Impact factor: 3.552, year: 2016

  3. Uptake of SPECT radiopharmaceuticals in neocortical brain cultures

    Energy Technology Data Exchange (ETDEWEB)

    Jong, B.M. de; Royen, E.A. van

    1989-01-01

    The uptake, retention and uptake antagonism of /sup 201/Tl-DDC, /sup 201/Tl-Cl, /sup 123/I-IMP, /sup 99m/Tc-HMPAO and /sup 99m/Tc-O4/sup -/ were compared in rat neocortex cultures. /sup 201/Tl-DDC and /sup 123/I-IP revealed the highest uptake of radioactivity in the cultures. /sup 99m/Tc-HMPAO and /sup 123/I-IMP showed the highest retention of radioactivity within the tissue in washout experiments. Blocking of bioelectric activity by tetrodotoxin did not significantly affect the uptake of the radiopharmaceuticals (RPHA). Inhibition of Na K ATPase by ouabain inhibited the uptake of /sup 201/Tl-Cl (77%) and /sup 201/Tl-DDC (27%). Imipramine showed a significantly stronger inhibitory effect on /sup 123/I-IMP uptake in comparison with the effect on other RPHA. /sup 99m/Tc-O4/sup -/ was not concentrated within the cultured tissue. Under the in vitro conditions used in this study, the various RPHA were characterised by distinct differences in their interaction with cortical brain tissue.

  4. Localization and pharmacological characterization of voltage dependent calcium channels in cultured neocortical neurons

    DEFF Research Database (Denmark)

    Timmermann, D B; Lund, Trine Meldgaard; Belhage, B

    2001-01-01

    The physiological significance and subcellular distribution of voltage dependent calcium channels was defined using calcium channel blockers to inhibit potassium induced rises in cytosolic calcium concentration in cultured mouse neocortical neurons. The cytosolic calcium concentration was measured...... channels were differentially distributed in somata, neurites and nerve terminals. omega-conotoxin MVIIC (omega-CgTx MVIIC) inhibited approximately 40% of the Ca(2+)-rise in both somata and neurites and 60% of the potassium induced [3H]GABA release, indicating that the Q-type channel is the quantitatively...... most important voltage dependent calcium channel in all parts of the neuron. After treatment with thapsigargin the increase in cytosolic calcium was halved, indicating that calcium release from thapsigargin sensitive intracellular calcium stores is an important component of the potassium induced rise...

  5. Oscillatory activity in neocortical networks during tactile discrimination near the limit of spatial acuity.

    Science.gov (United States)

    Adhikari, Bhim M; Sathian, K; Epstein, Charles M; Lamichhane, Bidhan; Dhamala, Mukesh

    2014-05-01

    Oscillatory interactions within functionally specialized but distributed brain regions are believed to be central to perceptual and cognitive functions. Here, using human scalp electroencephalography (EEG) recordings combined with source reconstruction techniques, we study how oscillatory activity functionally organizes different neocortical regions during a tactile discrimination task near the limit of spatial acuity. While undergoing EEG recordings, blindfolded participants felt a linear three-dot array presented electromechanically, under computer control, and reported whether the central dot was offset to the left or right. The average brain response differed significantly for trials with correct and incorrect perceptual responses in the timeframe approximately between 130 and 175ms. During trials with correct responses, source-level peak activity appeared in the left primary somatosensory cortex (SI) at around 45ms, in the right lateral occipital complex (LOC) at 130ms, in the right posterior intraparietal sulcus (pIPS) at 160ms, and finally in the left dorsolateral prefrontal cortex (dlPFC) at 175ms. Spectral interdependency analysis of activity in these nodes showed two distinct distributed networks, a dominantly feedforward network in the beta band (12-30Hz) that included all four nodes and a recurrent network in the gamma band (30-100Hz) that linked SI, pIPS and dlPFC. Measures of network activity in both bands were correlated with the accuracy of task performance. These findings suggest that beta and gamma band oscillatory networks coordinate activity between neocortical regions mediating sensory and cognitive processing to arrive at tactile perceptual decisions. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Development of calcium-permeable alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors in cultured neocortical neurons visualized by cobalt staining

    DEFF Research Database (Denmark)

    Jensen, J B; Schousboe, A; Pickering, D S

    1998-01-01

    The developmental expression of calcium (Ca2+)-permeable alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptors in cultured neocortical neurons was evaluated by using cobalt uptake, a histochemical method that identifies cells expressing Ca2+-permeable, non-N-methyl-D-aspartate...

  7. The neocortical network representing associative memory reorganizes with time in a process engaging the anterior temporal lobe.

    Science.gov (United States)

    Nieuwenhuis, Ingrid L C; Takashima, Atsuko; Oostenveld, Robert; McNaughton, Bruce L; Fernández, Guillén; Jensen, Ole

    2012-11-01

    During encoding, the distributed neocortical representations of memory components are presumed to be associatively linked by the hippocampus. With time, a reorganization of brain areas supporting memory takes place, which can ultimately result in memories becoming independent of the hippocampus. While it is theorized that with time, the neocortical representations become linked by higher order neocortical association areas, this remains to be experimentally supported. In this study, 24 human participants encoded sets of face-location associations, which they retrieved 1 or 25 h later ("recent" and "remote" conditions, respectively), while their brain activity was recorded using whole-head magnetoencephalography. We investigated changes in the functional interactions between the neocortical representational areas emerging over time. To assess functional interactions, trial-by-trial high gamma (60-140 Hz) power correlations were calculated between the neocortical representational areas relevant to the encoded information, namely the fusiform face area (FFA) and posterior parietal cortex (PPC). With time, both the FFA and the PPC increased their functional interactions with the anterior temporal lobe (ATL). Given that the ATL is involved in semantic representation of paired associates, our results suggest that, already within 25 h after acquiring new memory associations, neocortical functional links are established via higher order semantic association areas.

  8. Role of desensitization and subunit expression for kainate receptor-mediated neurotoxicity in murine neocortical cultures

    DEFF Research Database (Denmark)

    Jensen, J B; Schousboe, A; Pickering, D S

    1999-01-01

    ) toxicity mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors, and (3) toxicity that can be mediated by kainate receptors when desensitization of the receptors is blocked. The indirect action at NMDA receptors was discovered because (5R, 10S)-(+)-5-methyl-10,11-dihydro-5H...... nedioxy-5H-2,3-benzodiazepine (GYKI 53655), a selective AMPA receptor antagonist, abolished the remaining toxicity. These results indicated that kainate- and domoate-mediated toxicity involves both the NMDA and the AMPA receptors. Pretreatment of the cultures with concanavalin A to prevent desensitization...

  9. Determination of the phospholipid precursor of anandamide and other N- acylethanolamine phospholipids before and after sodium azide-induced toxicity in cultured neocortical neurons

    DEFF Research Database (Denmark)

    Hansen, H.H.; Schousboe, A.; Hansen, Harald S.

    2000-01-01

    Phospholipase D-mediated hydrolysis of N-acylethanolamine phospholipids (NAPEs) releases anandamide and other N-acylethanolamines, resulting in different actions at cellular targets in the CNS. Recently, we have demonstrated that these N-acyl lipids accumulate in cultured neocortical neurons subj...... method, neuronal NAPE species can be identified and quantified with respect to N-acyl composition, including a trans-isomer of the anandamide precursor. The anandamide precursor is up-regulated to the same extent as other NAPEs upon neuronal injury....

  10. Dynamic Network Drivers of Seizure Generation, Propagation and Termination in Human Neocortical Epilepsy

    Science.gov (United States)

    Khambhati, Ankit N.; Davis, Kathryn A.; Oommen, Brian S.; Chen, Stephanie H.; Lucas, Timothy H.; Litt, Brian; Bassett, Danielle S.

    2015-01-01

    The epileptic network is characterized by pathologic, seizure-generating ‘foci’ embedded in a web of structural and functional connections. Clinically, seizure foci are considered optimal targets for surgery. However, poor surgical outcome suggests a complex relationship between foci and the surrounding network that drives seizure dynamics. We developed a novel technique to objectively track seizure states from dynamic functional networks constructed from intracranial recordings. Each dynamical state captures unique patterns of network connections that indicate synchronized and desynchronized hubs of neural populations. Our approach suggests that seizures are generated when synchronous relationships near foci work in tandem with rapidly changing desynchronous relationships from the surrounding epileptic network. As seizures progress, topographical and geometrical changes in network connectivity strengthen and tighten synchronous connectivity near foci—a mechanism that may aid seizure termination. Collectively, our observations implicate distributed cortical structures in seizure generation, propagation and termination, and may have practical significance in determining which circuits to modulate with implantable devices. PMID:26680762

  11. Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator.

    Science.gov (United States)

    Drewes, Rich; Zou, Quan; Goodman, Philip H

    2009-01-01

    Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading "glue" tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS.

  12. Brainlab: a Python toolkit to aid in the design, simulation, and analysis of spiking neural networks with the NeoCortical Simulator

    Directory of Open Access Journals (Sweden)

    Richard P Drewes

    2009-05-01

    Full Text Available Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading ``glue'' tool for managing all sorts of complex programmatictasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS environment in particular. Brainlab is an integrated model building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS (the NeoCortical Simulator.

  13. Characterization of glutamate-induced formation of N- acylphosphatidylethanolamine and N-acylethanolamine in cultured neocortical neurons

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Lauritzen, L.; Strand, A.M.

    1997-01-01

    ) assay). The increase in NAPE and NAE could be detected earlier than the neuronal death. Neither cyclic AMP, cyclic GMP, nitric oxide, protein kinase C, nor peroxidation appears to be involved in the formation of NAPE and NAE, as assessed by the use of different pharmacological agents. Exposure to 5 m...... receptors as seen by the inhibitory action of the NMDA-selective receptor antagonists D(-)-2-amino-5-phosphonovalerate and N- (1-(2-thienyl)-cyclohexyl)piperidine and the lack of effect of the a-amino- 3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)/kainate-receptor antagonist 6-cyano-7-nitro......-quinoxaline-2,3-dione (CNQX). In 6-day-old cultures, exposure to NMDA (100 µM for 24 h) induced a linear increase in the formation of NAPE and NAE as well as a 40-50% neuronal death, as measured by a decrease in cellular formazan formation [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT...

  14. Influence of Pyrethroid Insecticides on Sodium and Calcium Influx in Neocortical Neurons

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    Pyrethroid insecticides bind to voltage-gated sodium channels and modify their gating kinetics, thereby disrupting neuronal function. Using murine neocortical neurons in primary culture, we have compared the ability of 11 structurally diverse pyrethroid insecticides to evoke Na+ ...

  15. Can Cultural Worldviews Influence Network Composition?

    Science.gov (United States)

    Vaisey, Stephen; Lizardo, Omar

    2010-01-01

    Most sociological research assumes that social network composition shapes individual beliefs. Network theory and research has not adequately considered that internalized cultural worldviews might affect network composition. Drawing on a synthetic, dual-process theory of culture and two waves of nationally-representative panel data, this article…

  16. Organizational Culture and Network Embeddedness

    NARCIS (Netherlands)

    Noorderhaven, N.G.; Koen, C.I.; Beugelsdijk, S.

    2002-01-01

    A question that has been neglected in network research is where differences in network embeddedness come from.The network literature reveals that there are three key characteristics of embedded relationships: trust, open communication, and joint problem solving.On the basis of the sparse empirical

  17. Effects of gap junction blockers on human neocortical synchronization.

    Science.gov (United States)

    Gigout, S; Louvel, J; Kawasaki, H; D'Antuono, M; Armand, V; Kurcewicz, I; Olivier, A; Laschet, J; Turak, B; Devaux, B; Pumain, R; Avoli, M

    2006-06-01

    Field potentials and intracellular recordings were obtained from human neocortical slices to study the role of gap junctions (GJ) in neuronal network synchronization. First, we examined the effects of GJ blockers (i.e., carbenoxolone, octanol, quinine, and quinidine) on the spontaneous synchronous events (duration = 0.2-1.1 s; intervals of occurrence = 3-27 s) generated by neocortical slices obtained from temporal lobe epileptic patients during application of 4-aminopyridine (4AP, 50 muM) and glutamatergic receptor antagonists. The synchronicity of these potentials (recorded at distances up to 5 mm) was decreased by GJ blockers within 20 min of application, while prolonged GJ blockers treatment at higher doses made them disappear with different time courses. Second, we found that slices from patients with focal cortical dysplasia (FCD) could generate in normal medium spontaneous synchronous discharges (duration = 0.4-8 s; intervals of occurrence = 0.5-90 s) that were (i) abolished by NMDA receptor antagonists and (ii) slowed down by carbenoxolone. Finally, octanol or carbenoxolone blocked 4AP-induced ictal-like discharges (duration = up to 35 s) in FCD slices. These data indicate that GJ play a role in synchronizing human neocortical networks and may implement epileptiform activity in FCD.

  18. Mobile Social Network in a Cultural Context

    DEFF Research Database (Denmark)

    Liu, Jun

    2010-01-01

    , and mobile phone rumours, this study observes that mobile social networks are a way that Chinese people cultivate, maintain and strengthen their guanxi networks. Embedding the reliability of guanxi, the message spreading via mobile communication always enjoys high credibility, while mutual obligation...... of mobile social network in China therefore emanate not only from Information and Communication Technologies, but also from the socio-cultural source - guanxi - deeply rooted in Chinese society.......the chapter “Mobile Social Network in a Cultural Context” examines the guanxi-embedded mobile social network in China. By focusing on three concrete case studies with 56 in-depth interviews, including New Year text message greetings, mobile social networks for job allocations among migrant workers...

  19. Convergent microRNA actions coordinate neocortical development.

    Science.gov (United States)

    Barca-Mayo, Olga; De Pietri Tonelli, Davide

    2014-08-01

    Neocortical development is a complex process that, at the cellular level, involves tight control of self-renewal, cell fate commitment, survival, differentiation and delamination/migration. These processes require, at the molecular level, the precise regulation of intrinsic signaling pathways and extrinsic factors with coordinated action in a spatially and temporally specific manner. Transcriptional regulation plays an important role during corticogenesis; however, microRNAs (miRNAs) are emerging as important post-transcriptional regulators of various aspects of central nervous system development. miRNAs are a class of small, single-stranded noncoding RNA molecules that control the expression of the majority of protein coding genes (i.e., targets). How do different miRNAs achieve precise control of gene networks during neocortical development? Here, we critically review all the miRNA-target interactions validated in vivo, with relevance to the generation and migration of pyramidal-projection glutamatergic neurons, and for the initial formation of cortical layers in the embryonic development of rodent neocortex. In particular, we focus on convergent miRNA actions, which are still a poorly understood layer of complexity in miRNA signaling, but potentially one of the keys to disclosing how miRNAs achieve the precise coordination of complex biological processes such as neocortical development.

  20. Neocortical layer 6, a review

    Directory of Open Access Journals (Sweden)

    Alex M Thomson

    2010-03-01

    Full Text Available This review attempts to summarise some of the major areas of neocortical research as it pertains to layer 6. After a brief summary of the development of this intriguing layer, the major pyramidal cell classes to be found in layer 6 are described and compared. The connections made and received by these different classes of neurones are then discussed and the possible functions of these connections, with particular reference to the shaping of responses in visual cortex and thalamus. Inhibition in layer 6 is discussed where appropriate, but not in great detail. Many types of interneurones are to be found in each cortical layer and layer 6 is no exception, but the functions of each type remain to be elucidated.

  1. Memory in cultured cortical networks

    NARCIS (Netherlands)

    le Feber, Jakob; Witteveen, T.; Stoyanova, Irina; Rutten, Wim

    2012-01-01

    Tetanic stimulation was applied to affect network connectivity, as assessed by conditional firing probabilities. We showed that the first period(s) of titanic stimulation at a certain electrode significantly alters functional connectivity, but subsequent, identical stimuli do not. These findings

  2. Safety culture and networks of influence

    International Nuclear Information System (INIS)

    Pereira, Carlos Henrique V.; Barroso, Antonio C.O.; Vieira Neto, Antonio S.

    2011-01-01

    This paper analyzes the social networks that influence the formation and maintenance of the safety culture within the Institute of Energy and Nuclear Research (IPEN-CNEN/SP). From the mapping and analysis of social networks, actors with a significant degree of influence were identified. Later using a questionnaire, the beliefs of the population sample were mapped. Thus, the importance of key actors in the network analysis could be confirmed statistically. Therefore, based on the mentioned methods we could demonstrate our hypothesis, that there are some social networks that are important in the formation of safety culture, as well as the fact that the influence of some distinguished actors plays an essential role in this amalgam. (author)

  3. Safety culture and networks of influence

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Carlos Henrique V.; Barroso, Antonio C.O.; Vieira Neto, Antonio S., E-mail: carloshvp@usp.br, E-mail: barroso@ipen.br, E-mail: asvneto@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    This paper analyzes the social networks that influence the formation and maintenance of the safety culture within the Institute of Energy and Nuclear Research (IPEN-CNEN/SP). From the mapping and analysis of social networks, actors with a significant degree of influence were identified. Later using a questionnaire, the beliefs of the population sample were mapped. Thus, the importance of key actors in the network analysis could be confirmed statistically. Therefore, based on the mentioned methods we could demonstrate our hypothesis, that there are some social networks that are important in the formation of safety culture, as well as the fact that the influence of some distinguished actors plays an essential role in this amalgam. (author)

  4. Lipopolysaccharide (LPS Accumulates in Neocortical Neurons of Alzheimer’s Disease (AD Brain and Impairs Transcription in Human Neuronal-Glial Primary Co-cultures

    Directory of Open Access Journals (Sweden)

    Yuhai Zhao

    2017-12-01

    Full Text Available Several independent laboratories have recently reported the detection of bacterial nucleic acid sequences or bacterial-derived neurotoxins, such as highly inflammatory lipopolysaccharide (LPS, within Alzheimer’s disease (AD affected brain tissues. Whether these bacterial neurotoxins originate from the gastrointestinal (GI tract microbiome, a possible brain microbiome or some dormant pathological microbiome is currently not well understood. Previous studies indicate that the co-localization of pro-inflammatory LPS with AD-affected brain cell nuclei suggests that there may be a contribution of this neurotoxin to genotoxic events that support inflammatory neurodegeneration and failure in homeostatic gene expression. In this report we provide evidence that in sporadic AD, LPS progressively accumulates in neuronal parenchyma and appears to preferentially associate with the periphery of neuronal nuclei. Run-on transcription studies utilizing [α-32P]-uridine triphosphate incorporation into newly synthesized total RNA further indicates that human neuronal-glial (HNG cells in primary co-culture incubated with LPS exhibit significantly reduced output of DNA transcription products. These studies suggest that in AD LPS may impair the efficient readout of neuronal genetic information normally required for the homeostatic operation of brain cell function and may contribute to a progressive disruption in the read-out of genetic information.

  5. Entrepreneurial networks as culturally embedded phenomena

    Directory of Open Access Journals (Sweden)

    Vlatka Skokic

    2015-06-01

    Full Text Available Entrepreneurship research concerning networks has largely focused on network structure, content and governance. We believe that further research is required in order to gain a richer understanding of why specific network forms and types originated. The purpose of this paper is to explore the existence, importance, values and meanings of both the informal and formal networks and networking behaviours of small-scale hotel owner-managers embedded in the socio-economic context of Croatia. In order to gain richer and more detailed understanding of entrepreneurial networks and to understand the influence of socio-economic setting on entrepreneurial networking, we have employed qualitative, in-depth study with small hotel owners. Results suggest that entrepreneurs do not establish strong personal and firm-to-firm ties, but rather focus on formal associations. Reported findings identify socio-cultural factors apparently unique to the context of former socialist economy which have the potential to explain the reported networking behaviour. The adopted research approach brings another dimension to existing theoretical underpinnings, which can encourage researchers to extend or revise theories with new contextual variables.

  6. Is attentional blink a byproduct of neocortical attractors?

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    David N Silverstein

    2011-05-01

    Full Text Available This study proposes a computational model for attentional blink or blink of the mind, a phenomenon where a human subject misses perception of a later expected visual pattern as two expected visual patterns are presented less than 500 ms apart. A neocortical patch modeled as an attractor network is stimulated with a sequence of 14 patterns 100 ms apart, two of which are expected targets. Patterns that become active attractors are considered recognized. A neocortical patch is represented as a square matrix of hypercolumns, each containing a set of minicolumns with synaptic connections within and across both minicolumns and hypercolumns. Each minicolumn consists of locally connected layer 2/3 pyramidal cells with interacting basket cells and layer 4 pyramidal cells for input stimulation. All neurons are implemented using the Hodgkin-Huxley multi-compartmental cell formalism and include calcium dynamics, and they interact via saturating and depressing AMPA / NMDA and GABAA synapses. Stored patterns are encoded with global connectivity of minicolumns across hypercolumns and active patterns compete as the result of lateral inhibition in the network. Stored patterns were stimulated over time intervals to create attractor interference measurable with synthetic spike traces. This setup corresponds with item presentations in human visual attentional blink studies. Stored target patterns were depolarized while distractor patterns where hyperpolarized to represent expectation of items in working memory. Additionally, studies on the inhibitory effect of benzodiazopines on attentional blink in human subjects were compared with neocortical simulations where the GABAA receptor conductance and decay time were increased. Simulations showed increases in the attentional blink duration, agreeing with observations in human studies.

  7. Neocortical arealization: evolution, mechanisms, and open questions.

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    Alfano, Christian; Studer, Michèle

    2013-06-01

    The mammalian neocortex is a structure with no equals in the vertebrates and is the seat of the highest cerebral functions, such as thoughts and consciousness. It is radially organized into six layers and tangentially subdivided into functional areas deputed to the elaboration of sensory information, association between different stimuli, and selection and triggering of voluntary movements. The process subdividing the neocortical field into several functional areas is called "arealization". Each area has its own cytoarchitecture, connectivity, and peculiar functions. In the last century, several neuroscientists have investigated areal structure and the mechanisms that have led during evolution to the rising of the neocortex and its organization. The extreme conservation in the positioning and wiring of neocortical areas among different mammalian families suggests a conserved genetic program orchestrating neocortical patterning. However, the impressive plasticity of the neocortex, which is able to rewire and reorganize areal structures and connectivity after impairments of sensory pathways, argues for a more complex scenario. Indeed, even if genetics and molecular biology helped in identifying several genes involved in the arealization process, the logic underlying the neocortical bauplan is still beyond our comprehension. In this review, we will introduce the present knowledge and hypotheses on the ontogenesis and evolution of neocortical areas. Then, we will focus our attention on some open issues, which are still unresolved, and discuss some recent studies that might open new directions to be explored in the next few years. Copyright © 2012 Wiley Periodicals, Inc.

  8. An essential role for neuregulin-4 in the growth and elaboration of developing neocortical pyramidal dendrites.

    Science.gov (United States)

    Paramo, Blanca; Wyatt, Sean; Davies, Alun M

    2018-04-01

    Neuregulins, with the exception of neuregulin-4 (NRG4), have been shown to be extensively involved in many aspects of neural development and function and are implicated in several neurological disorders, including schizophrenia, depression and bipolar disorder. Here we provide the first evidence that NRG4 has a crucial function in the developing brain. We show that both the apical and basal dendrites of neocortical pyramidal neurons are markedly stunted in Nrg4 -/- neonates in vivo compared with Nrg4 +/+ littermates. Neocortical pyramidal neurons cultured from Nrg4 -/- embryos had significantly shorter and less branched neurites than those cultured from Nrg4 +/+ littermates. Recombinant NRG4 rescued the stunted phenotype of embryonic neocortical pyramidal neurons cultured from Nrg4 -/- mice. The majority of cultured wild type embryonic cortical pyramidal neurons co-expressed NRG4 and its receptor ErbB4. The difference between neocortical pyramidal dendrites of Nrg4 -/- and Nrg4 +/+ mice was less pronounced, though still significant, in juvenile mice. However, by adult stages, the pyramidal dendrite arbors of Nrg4 -/- and Nrg4 +/+ mice were similar, suggesting that compensatory changes in Nrg4 -/- mice occur with age. Our findings show that NRG4 is a major novel regulator of dendritic arborisation in the developing cerebral cortex and suggest that it exerts its effects by an autocrine/paracrine mechanism. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Neocortical glial cell numbers in human brains

    DEFF Research Database (Denmark)

    Pelvig, D.P.; Pakkenberg, H.; Stark, A.K.

    2008-01-01

    Stereological cell counting was applied to post-mortem neocortices of human brains from 31 normal individuals, age 18-93 years, 18 females (average age 65 years, range 18-93) and 13 males (average age 57 years, range 19-87). The cells were differentiated in astrocytes, oligodendrocytes, microglia...... while the total astrocyte number is constant through life; finally males have a 28% higher number of neocortical glial cells and a 19% higher neocortical neuron number than females. The overall total number of neocortical neurons and glial cells was 49.3 billion in females and 65.2 billion in males...... and neurons and counting were done in each of the four lobes. The study showed that the different subpopulations of glial cells behave differently as a function of age; the number of oligodendrocytes showed a significant 27% decrease over adult life and a strong correlation to the total number of neurons...

  10. Hamlet, Performance and Chaotic Cultural Networks

    Directory of Open Access Journals (Sweden)

    Emil Rybczak

    2015-10-01

    Full Text Available Since the 1960s, chaos theory has become an important but controversial tool used by scientists and mathematicians to describe physical or theoretical systems or networks. It explains how the simple can generate the complex. Its central tenets can also provide an alternative language and means of literary interpretation. This article will explore how the principles of chaos theory can be used to close read and systematise various aspects of the language and performance of Shakespeare. The argument is built upon an analysis of Hamlet, in an effort to understand the play and its reproduction as the evolution of interconnected complex networks. Various aspects of the text will be discussed, including its language, structural and character patterning, and its reproduction through performance and cinematic adaptation. Each of these topics, and the characters, devices or ideas they discuss, constitute nodes of the complex network of Hamlet as both text and idea. Responding to the cultural analysis of other scholars, this article uses Hamlet as an ideal example of how the appropriation of scientific language can defamiliarise a particular literary or dramatic artefact. This allows fresh interpretation and understanding of its location within the broader networks of theatre and culture. I suggest the possibilities of close reading literary works through the lens of chaos and suggest how they might be applied and developed in conjunction with other texts, media or performances.

  11. Spike Code Flow in Cultured Neuronal Networks.

    Science.gov (United States)

    Tamura, Shinichi; Nishitani, Yoshi; Hosokawa, Chie; Miyoshi, Tomomitsu; Sawai, Hajime; Kamimura, Takuya; Yagi, Yasushi; Mizuno-Matsumoto, Yuko; Chen, Yen-Wei

    2016-01-01

    We observed spike trains produced by one-shot electrical stimulation with 8 × 8 multielectrodes in cultured neuronal networks. Each electrode accepted spikes from several neurons. We extracted the short codes from spike trains and obtained a code spectrum with a nominal time accuracy of 1%. We then constructed code flow maps as movies of the electrode array to observe the code flow of "1101" and "1011," which are typical pseudorandom sequence such as that we often encountered in a literature and our experiments. They seemed to flow from one electrode to the neighboring one and maintained their shape to some extent. To quantify the flow, we calculated the "maximum cross-correlations" among neighboring electrodes, to find the direction of maximum flow of the codes with lengths less than 8. Normalized maximum cross-correlations were almost constant irrespective of code. Furthermore, if the spike trains were shuffled in interval orders or in electrodes, they became significantly small. Thus, the analysis suggested that local codes of approximately constant shape propagated and conveyed information across the network. Hence, the codes can serve as visible and trackable marks of propagating spike waves as well as evaluating information flow in the neuronal network.

  12. Spike Code Flow in Cultured Neuronal Networks

    Directory of Open Access Journals (Sweden)

    Shinichi Tamura

    2016-01-01

    Full Text Available We observed spike trains produced by one-shot electrical stimulation with 8 × 8 multielectrodes in cultured neuronal networks. Each electrode accepted spikes from several neurons. We extracted the short codes from spike trains and obtained a code spectrum with a nominal time accuracy of 1%. We then constructed code flow maps as movies of the electrode array to observe the code flow of “1101” and “1011,” which are typical pseudorandom sequence such as that we often encountered in a literature and our experiments. They seemed to flow from one electrode to the neighboring one and maintained their shape to some extent. To quantify the flow, we calculated the “maximum cross-correlations” among neighboring electrodes, to find the direction of maximum flow of the codes with lengths less than 8. Normalized maximum cross-correlations were almost constant irrespective of code. Furthermore, if the spike trains were shuffled in interval orders or in electrodes, they became significantly small. Thus, the analysis suggested that local codes of approximately constant shape propagated and conveyed information across the network. Hence, the codes can serve as visible and trackable marks of propagating spike waves as well as evaluating information flow in the neuronal network.

  13. Exporting embedded in culture and transnational networks around entrepreneurs

    DEFF Research Database (Denmark)

    Ashourizadeh, Shayegheh; Schøtt, Thomas

    2016-01-01

    from networking in the market, professions and work-place, but is impeded by networking for advice in the private sphere. Exporting is embedded in culture in the way that benefits of transnational networking for exporting are higher in secular-rational culture than in traditional culture. This study....... This dynamic unfolds in the context of culture, which expectedly moderates benefit of networks for exporting. Networking for advice was surveyed in the Global Entrepreneurship Monitor in 61 societies with 52,968 entrepreneurs. Exporting greatly benefits from transnational networks around entrepreneurs and also...... generalises to the entrepreneurs in the world, and is a first to account for embedding of exporting in transnational advisory networks in combination with culture....

  14. Neocortical Development in Brain of Young Children

    DEFF Research Database (Denmark)

    Kjaer, Majken; Fabricius, Katrine; Sigaard, Rasmus Krarup

    2017-01-01

    The early postnatal development of neuron and glia numbers is poorly documented in human brain. Therefore we estimated using design-based stereological methods the regional volumes of neocortex and the numbers of neocortical neurons and glial cells for 10 children (4 girls and 6 boys), ranging from...... neonate to 3 years of age. The 10 infants had a mean of 20.7 × 109 neocortical neurons (range 18.0-24.8 × 109) estimated with a coefficient of variation (CV) = 0.11; this range is similar to adult neuron numbers. The glia populations were 10.5 × 109 oligodendrocytes (range 5.0-16.0 × 109; CV = 0.40); 5...

  15. Incorporating rapid neocortical learning of new schema-consistent information into complementary learning systems theory.

    Science.gov (United States)

    McClelland, James L

    2013-11-01

    The complementary learning systems theory of the roles of hippocampus and neocortex (McClelland, McNaughton, & O'Reilly, 1995) holds that the rapid integration of arbitrary new information into neocortical structures is avoided to prevent catastrophic interference with structured knowledge representations stored in synaptic connections among neocortical neurons. Recent studies (Tse et al., 2007, 2011) showed that neocortical circuits can rapidly acquire new associations that are consistent with prior knowledge. The findings challenge the complementary learning systems theory as previously presented. However, new simulations extending those reported in McClelland et al. (1995) show that new information that is consistent with knowledge previously acquired by a putatively cortexlike artificial neural network can be learned rapidly and without interfering with existing knowledge; it is when inconsistent new knowledge is acquired quickly that catastrophic interference ensues. Several important features of the findings of Tse et al. (2007, 2011) are captured in these simulations, indicating that the neural network model used in McClelland et al. has characteristics in common with neocortical learning mechanisms. An additional simulation generalizes beyond the network model previously used, showing how the rate of change of cortical connections can depend on prior knowledge in an arguably more biologically plausible network architecture. In sum, the findings of Tse et al. are fully consistent with the idea that hippocampus and neocortex are complementary learning systems. Taken together, these findings and the simulations reported here advance our knowledge by bringing out the role of consistency of new experience with existing knowledge and demonstrating that the rate of change of connections in real and artificial neural networks can be strongly prior-knowledge dependent. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  16. Neocortical glial cell numbers in human brains.

    Science.gov (United States)

    Pelvig, D P; Pakkenberg, H; Stark, A K; Pakkenberg, B

    2008-11-01

    Stereological cell counting was applied to post-mortem neocortices of human brains from 31 normal individuals, age 18-93 years, 18 females (average age 65 years, range 18-93) and 13 males (average age 57 years, range 19-87). The cells were differentiated in astrocytes, oligodendrocytes, microglia and neurons and counting were done in each of the four lobes. The study showed that the different subpopulations of glial cells behave differently as a function of age; the number of oligodendrocytes showed a significant 27% decrease over adult life and a strong correlation to the total number of neurons while the total astrocyte number is constant through life; finally males have a 28% higher number of neocortical glial cells and a 19% higher neocortical neuron number than females. The overall total number of neocortical neurons and glial cells was 49.3 billion in females and 65.2 billion in males, a difference of 24% with a high biological variance. These numbers can serve as reference values in quantitative studies of the human neocortex.

  17. Default activity patterns at the neocortical microcircuit level

    Directory of Open Access Journals (Sweden)

    Artur eLuczak

    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.

  18. Analysis of organizational culture with social network models

    OpenAIRE

    Titov, S.

    2015-01-01

    Organizational culture is nowadays an object of numerous scientific papers. However, only marginal part of existing research attempts to use the formal models of organizational cultures. The lack of organizational culture models significantly limits the further research in this area and restricts the application of the theory to practice of organizational culture change projects. The article consists of general views on potential application of network models and social network analysis to th...

  19. Cultural Ecosystem of Creative Place: Creative Class, Creative Networks and Participation in Culture

    Directory of Open Access Journals (Sweden)

    Anders-Morawska Justyna

    2017-06-01

    Full Text Available The scope of this paper is to conceptualise a data-based research framework for the role of creative networks in cultural exchange. Participation in culture measured as audience per 1000 residents and expenditures on culture-related activities were analysed in relation to such territorial assets as accessibility to creative infrastructure, the economic status of residents, the governance networks of civil society, and cultural capital. The results indicate how accessibility, governance networks, and cultural capital contribute to participation measured via audience indicators while a low poverty rate has explanatory value with respect to expenditures on culture.

  20. Functional clustering in hippocampal cultures: relating network structure and dynamics

    International Nuclear Information System (INIS)

    Feldt, S; Dzakpasu, R; Olariu, E; Żochowski, M; Wang, J X; Shtrahman, E

    2010-01-01

    In this work we investigate the relationship between gross anatomic structural network properties, neuronal dynamics and the resultant functional structure in dissociated rat hippocampal cultures. Specifically, we studied cultures as they developed under two conditions: the first supporting glial cell growth (high glial group), and the second one inhibiting it (low glial group). We then compared structural network properties and the spatio-temporal activity patterns of the neurons. Differences in dynamics between the two groups could be linked to the impact of the glial network on the neuronal network as the cultures developed. We also implemented a recently developed algorithm called the functional clustering algorithm (FCA) to obtain the resulting functional network structure. We show that this new algorithm is useful for capturing changes in functional network structure as the networks evolve over time. The FCA detects changes in functional structure that are consistent with expected dynamical differences due to the impact of the glial network. Cultures in the high glial group show an increase in global synchronization as the cultures age, while those in the low glial group remain locally synchronized. We additionally use the FCA to quantify the amount of synchronization present in the cultures and show that the total level of synchronization in the high glial group is stronger than in the low glial group. These results indicate an interdependence between the glial and neuronal networks present in dissociated cultures

  1. Exploration of Online Culture Through Network Analysis of Wikipedia.

    Science.gov (United States)

    Park, Sung Joo; Kim, Jong Woo; Lee, Hong Joo; Park, Hyunjung; Han, Deugcheon; Gloor, Peter

    2015-11-01

    Understanding online culture is becoming crucial in the global and connected world. Contrary to conventional attitudinal surveys used in cultural research, this study uses the approach of directly observing culture-specific behavior that emerges from online collaboration on the Internet. The editing data of Wikipedia were analyzed in 12 languages. Distinctive cultural dimensions were identified, including collectivism, extraversion, boldness, and egalitarianism. Using network analysis, the language-framed cultural factors were extracted as an emergent phenomenon in the virtual world.

  2. Education for a Culture of Peace: The Culture of Peace News Network as a Case Study

    Science.gov (United States)

    Adams, David

    2013-01-01

    The Culture of Peace News Network, an internet news service, is analyzed in the framework of a general approach to education for a culture of peace. Its format reflects the eight program areas for a culture of peace as adopted by the UN General Assembly. Among its other operating principles are universality of news with all cultures and regions of…

  3. Global Diffusion of Interactive Networks. The Impact of Culture

    OpenAIRE

    Maitland, Carleen

    1998-01-01

    The Internet and other interactive networks are diffusing across the globe at rates that vary from country to country. Typically, economic and market structure variables are used to explain these differences. The addition of culture to these variables will provide a more robust understanding of the differences in Internet and interactive network diffusion. Existing analyses that identify culture as a predictor of diffusion do not adequately specificy the dimensions of culture and their imp...

  4. Levels, Linkages, and Networks in Cross-Cultural Innovation.

    Science.gov (United States)

    Kennedy, Judith; Kennedy, Chris

    1998-01-01

    Individuals belong to different cultural networks, and these networks and connections between them play an important role in success or failure of educational innovation and should be included in any model of the management or evaluation of innovation. Looks at functions of the different networks to which individuals belong at three levels,…

  5. Functional Maps of Neocortical Local Circuitry

    Science.gov (United States)

    Thomson, Alex M.; Lamy, Christophe

    2007-01-01

    This review aims to summarize data obtained with different techniques to provide a functional map of the local circuit connections made by neocortical neurones, a reference for those interested in cortical circuitry and the numerical information required by those wishing to model the circuit. A brief description of the main techniques used to study circuitry is followed by outline descriptions of the major classes of neocortical excitatory and inhibitory neurones and the connections that each layer makes with other cortical and subcortical regions. Maps summarizing the projection patterns of each class of neurone within the local circuit and tables of the properties of these local circuit connections are provided. This review relies primarily on anatomical studies that have identified the classes of neurones and their local and long distance connections and on paired intracellular and whole-cell recordings which have documented the properties of the connections between them. A large number of different types of synaptic connections have been described, but for some there are only a few published examples and for others the details that can only be obtained with paired recordings and dye-filling are lacking. A further complication is provided by the range of species, technical approaches and age groups used in these studies. Wherever possible the range of available data are summarised and compared. To fill some of the more obvious gaps for the less well-documented cases, data obtained with other methods are also summarized. PMID:18982117

  6. Closed Loop Brain Model of Neocortical Information Based Exchange

    Directory of Open Access Journals (Sweden)

    James eKozloski

    2016-01-01

    Full Text Available Here we describe an information based exchange' model of brain function that ascribes to neocortex, basal ganglia, and thalamus distinct network functions. The model allows us to analyze whole brain system set point measures, such as the rate and heterogeneity of transitions in striatum and neocortex, in the context of neuromodulation and other perturbations. Our closed-loop model is grounded in neuroanatomical observations, proposing a novel Grand Loop through neocortex, and invokes different forms of plasticity at specific tissue interfaces and their principle cell synapses to achieve these transitions. By implementing a system for maximum information based exchange of action potentials between modeled neocortical areas, we observe changes to these measures in simulation. We hypothesize that similar dynamic set points and modulations exist in the brain's resting state activity, and that different modifications to information based exchange may shift the risk profile of different component tissues, resulting in different neurodegenerative diseases. This model is targeted for further development using IBM's Neural Tissue Simulator, which allows scalable elaboration of networks, tissues, and their neural and synaptic components towards ever greater complexity and biological realism.

  7. Maintenance of cultural diversity: social roles, social networks, and cognitive networks.

    Science.gov (United States)

    Abrams, Marshall

    2014-06-01

    Smaldino suggests that patterns that give rise to group-level cultural traits can also increase individual-level cultural diversity. I distinguish social roles and related social network structures and discuss ways in which each might maintain diversity. I suggest that cognitive analogs of "cohesion," a property of networks that helps maintenance of diversity, might mediate the effects of social roles on diversity.

  8. Neocortical gamma oscillations in idiopathic generalized epilepsy

    DEFF Research Database (Denmark)

    Benedek, Krisztina; Berenyi, Antal; Gombkoto, Peter

    2016-01-01

    Objective: Absence seizures in patients with idiopathic generalized epilepsy (IGE) may in part be explained by a decrease in phasic GABAA (type-A c-aminobutyric acid) receptor function, but the mechanisms are only partly understood. Here we studied the relation between ictal and interictal spike......-wave discharges (SWDs) and electroencephalography (EEG) gamma oscillatory activity (30-60 Hz) in patients with IGE. Methods: EEG recordings were obtained of 14 children with IGE (mean age, 8.5 +/- 5 years) and 14 age-and sex-matched controls. Time-frequency analysis of each seizure and seizure-free control epochs...... was performed and cross-coherences of neocortical gamma oscillations were calculated to describe interictal and ictal characteristics of generalized seizures. Results: SWDs were characterized with an abrupt increase of oscillatory activity of 34 and 13-60 Hz, peaking at 3-4 and 30-60 Hz, and with a simultaneous...

  9. Community-centred Networks and Networking among Companies, Educational and Cultural Institutions and Research

    DEFF Research Database (Denmark)

    Konnerup, Ulla; Dirckinck-Holmfeld, Lone

    2010-01-01

    This article presents visions for community-centred networks and networking among companies, educational and cultural institutions and research based on blended on- and off-line collaboration and communication. Our point of departure is the general vision of networking between government, industry...... and research as formulated in the Triple Helix Model (Etzkowitz 2008). The article draws on a case study of NoEL, a network on e-learning among business, educational and cultural institutions and research, all in all 21 partners from all around Denmark. Focus is how networks and networking change character......’ in Networked Learning, Wenger et al. 2009; The analysis concerns the participation structure and how the network activities connect local work practices and research, and how technology and online communication contribute to a change from participation in offline and physical network activities into online...

  10. Coevolutionary network approach to cultural dynamics controlled by intolerance

    Science.gov (United States)

    Gracia-Lázaro, Carlos; Quijandría, Fernando; Hernández, Laura; Floría, Luis Mario; Moreno, Yamir

    2011-12-01

    Starting from Axelrod's model of cultural dissemination, we introduce a rewiring probability, enabling agents to cut the links with their unfriendly neighbors if their cultural similarity is below a tolerance parameter. For low values of tolerance, rewiring promotes the convergence to a frozen monocultural state. However, intermediate tolerance values prevent rewiring once the network is fragmented, resulting in a multicultural society even for values of initial cultural diversity in which the original Axelrod model reaches globalization.

  11. NETWORK CULTURE - INTEGRAL PART OF NEW VALUES OF CIVIL SOCIETY

    OpenAIRE

    Vyacheslav Vladimirovich Sukhanov

    2014-01-01

    New technologies not only improve working conditions or communication, they are also bringing new values to  the society. This article discusses the concept of «network culture», which is now perceived by society as an integral part of values that can only exist in a civil society. We can research ( find)   this kind of society in modern time period in Russia. The article analyzes the meaning of communication, how to use it, development processes in network media.  Nowadays network culture an...

  12. Social networks and family violence in cross-cultural perspective.

    Science.gov (United States)

    Korbin, J E

    1995-01-01

    The purpose of this chapter was twofold. First, the chapter put forward a brief cross-cultural perspective indicating that multiple types of intrafamilial violence occur cross-culturally. Second, the chapter placed social networks at the core of a complex etiology of intrafamilial violence. The purpose of giving centrality to social networks is not to suggest that social networks are the sole or primary agent contributing to family violence but to broaden the context in which family violence is viewed beyond that of the perpetrator, the victim/survivor, or the violent dyad.

  13. Learning by Knowledge Networking across Cultures

    DEFF Research Database (Denmark)

    Wangel, Arne; Stærdahl, Jens; Bransholm Pedersen, Kirsten

    2005-01-01

    Engineers and planners working in trans-national production and aid project interventions in Third World countries must be able to 're-invent' technological systems across cultures and plan and build the capacities of their counterparts. A series of joint courses on cleaner production (CP......) and environmental impact assessment (EIA) in Malaysia 1998-2003 has sought to address these needs for new competences. Differences in educational background and the work culture of the participants have presented difficulties during these courses, in particular in terms of achieving a mixed team building to turn...... some of the obstacles into resources for knowledge sharing. However, students have stressed their positive experience of cross-cultural communication. While a joint course of three week duration by itself may involve only limited cross-cultural learning, serving primarily as an introduction to a long...

  14. Cultural competence and social relationships: a social network analysis.

    Science.gov (United States)

    Dauvrin, M; Lorant, V

    2017-06-01

    This study investigated the role of social relationships in the sharing of cultural competence by testing two hypotheses: cultural competence is a socially shared behaviour; and central healthcare professionals are more culturally competent than non-central healthcare professionals. Sustaining cultural competence in healthcare services relies on the assumption that being culturally competent is a socially shared behaviour among health professionals. This assumption has never been tested. Organizational aspects surrounding cultural competence are poorly considered. This therefore leads to a heterogeneous implementation of cultural competence - especially in continental Europe. We carried out a social network analysis in 24 Belgian inpatient and outpatient health services. All healthcare professionals (ego) were requested to fill in a questionnaire (Survey on social relationships of health care professionals) on their level of cultural competence and to identify their professional relationships (alter). We fitted regression models to assess whether (1) at the dyadic level, ego cultural competence was associated with alter cultural competence, and (2) health professionals of greater centrality had greater cultural competence. At the dyadic level, no significant associations were found between ego cultural competence and alter cultural competence, with the exception of subjective exposure to intercultural situations. No significant associations were found between centrality and cultural competence, except for subjective exposure to intercultural situations. Being culturally competent is not a shared behaviour among health professionals. The most central healthcare professionals are not more culturally competent than less central health professionals. Culturally competent health care is not yet a norm in health services. Health care and training authorities should either make cultural competent health care a licensing criteria or reward culturally competent health care

  15. Networking - concepts and dimensions of the cross-cultural comparative study

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2000-01-01

    The litarature about networking is weak regarding precise definitions of networking and methodologies to analyse how networking is carried out in practice. Besides, the croos cultural dimension is often underestimated.......The litarature about networking is weak regarding precise definitions of networking and methodologies to analyse how networking is carried out in practice. Besides, the croos cultural dimension is often underestimated....

  16. Hidden neuronal correlations in cultured networks

    International Nuclear Information System (INIS)

    Segev, Ronen; Baruchi, Itay; Hulata, Eyal; Ben-Jacob, Eshel

    2004-01-01

    Utilization of a clustering algorithm on neuronal spatiotemporal correlation matrices recorded during a spontaneous activity of in vitro networks revealed the existence of hidden correlations: the sequence of synchronized bursting events (SBEs) is composed of statistically distinguishable subgroups each with its own distinct pattern of interneuron spatiotemporal correlations. These findings hint that each of the SBE subgroups can serve as a template for coding, storage, and retrieval of a specific information

  17. Networked Cultures in the Collaborative Economy

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia

    2017-01-01

    , and together open up for multidimensional interpretations of social exchange in the collaborative economy. The chapter concludes with a critical reflection on the challenges of understanding the collaborative economy in tourism, particularly when discourses are dominated by a communitarian logic......This chapter charts diverse approaches to conceptualizing the cultures of connection characterizing the collaborative economy. To decode the “we-conomy”, we revisit classic notions of coexistence, collaboration and bonding in communities. Informed by a multidisciplinary review (touching upon human...... ecology, sociology, anthropology and cultural theory), the chapter identifies distinct theoretical frameworks to describe the constitution of communities and discusses their relevance to the collaborative economy. These frameworks explain the drivers of communitarian behavior and resource circulation...

  18. Network bursts in cortical neuronal cultures: 'noise - versus pacemaker'- driven neural network simulations

    NARCIS (Netherlands)

    Gritsun, T.; Stegenga, J.; le Feber, Jakob; Rutten, Wim

    2009-01-01

    In this paper we address the issue of spontaneous bursting activity in cortical neuronal cultures and explain what might cause this collective behavior using computer simulations of two different neural network models. While the common approach to acivate a passive network is done by introducing

  19. PET imaging of neocortical monoaminergic terminals in Parkinson's disease

    International Nuclear Information System (INIS)

    Marie, R.M.; Barre, L.; Rioux, P.; Allain, P.; Lechevalier, B.; Baron, J.C.

    1995-01-01

    Post-mortem neurochemical studies in Parkinson's disease (PD) have shown that, in addition to the typical nigro-striatal dopamine denervation, there exists a concomitant neocortical monoamine fibre deafferentation (of variable severity) whose role in motor, and especially in associated cognitive and affective impairment, remains elusive. We have extensively examined whether PET imaging with 11 C-S-Nomifensine ( 11 C-NMF), a radioligand of the dopamine and norepinephrine presynaptic reuptake sites which has been used so far to investigate the striatum, could provide a method for assessing in vivo the neocortical monoamine terminal loss in PD; previously, this has been a little addressed and controversial issue. To this end, we prospectively selected a highly homogeneous sample of nine non-demented, non-depressed idiopathic PD patients with mild to marked side-to-side asymmetry in motor impairment. In addition to recovering the previously-reported correlations with putaminal 11 C-NMF specific uptake asymmetries, the clinical motor asymmetries also significantly correlated in the clinically expected direction to neocortical (especially frontal) 11 C-NMF asymmetries. suggesting the monoamine neocortical denervation might play a direct role in motor impairment in PD. These results demonstrate that it is possible to assess in vivo the neocortical monoamine terminal loss. and to elucidate its potential role in the complex cognitive and affective impairment, in both PD and atypical degenerative parkinsonism. (author)

  20. Patterns of hippocampal-neocortical interactions in the retrieval of episodic autobiographical memories across the entire life-span of aged adults

    Science.gov (United States)

    Viard, Armelle; Lebreton, Karine; Chételat, Gaël; Desgranges, Béatrice; Landeau, Brigitte; Young, Alan; De La Sayette, Vincent; Eustache, Francis; Piolino, Pascale

    2010-01-01

    We previously demonstrated that Episodic Autobiographical Memories (EAMs) rely on a network of brain regions comprising the medial temporal lobe (MTL) and distributed neocortical regions regardless of their remoteness. The findings supported the model of memory consolidation which proposes a permanent role of MTL during EAM retrieval (Multiple-Trace Theory or MTT) rather than a temporary role (standard model). Our present aim was to expand the results by examining the interactions between the MTL and neocortical regions (or MTL-neocortical links) during EAM retrieval with varying retention intervals. We used an experimental paradigm specially designed to engage aged participants in the recollection of EAMs, extracted from five different time-periods, covering their whole life-span, in order to examine correlations between activation in the MTL and neocortical regions. The nature of the memories was checked at debriefing by means of behavioral measures to control the degree of episodicity and properties of memories. Targeted correlational analyses carried out on the MTL, frontal, lateral temporal and posterior regions revealed strong links between the MTL and neocortex during the retrieval of both recent and remote EAMs, challenging the standard model of memory consolidation and supporting MTT instead. Further confirmation was given by results showing that activation in the left and right hippocampi significantly correlated during the retrieval of both recent and remote memories. Correlations among extra-MTL neocortical regions also emerged for all time-periods, confirming the critical role of the prefrontal, temporal (lateral temporal cortex and temporal pole), precuneus and posterior cingulate regions in EAM retrieval. Overall, this paper emphasizes the role of a bilateral network of MTL and neocortical areas whose activation correlate during the recollection of rich phenomenological recent and remote EAMs. PMID:19338022

  1. The United States Culture Collection Network (USCCN): Enhancing Microbial Genomics Research through Living Microbe Culture Collections

    Science.gov (United States)

    Boundy-Mills, Kyria; Hess, Matthias; Bennett, A. Rick; Ryan, Matthew; Kang, Seogchan; Nobles, David; Eisen, Jonathan A.; Inderbitzin, Patrik; Sitepu, Irnayuli R.; Torok, Tamas; Brown, Daniel R.; Cho, Juliana; Wertz, John E.; Mukherjee, Supratim; Cady, Sherry L.

    2015-01-01

    The mission of the United States Culture Collection Network (USCCN; http://usccn.org) is “to facilitate the safe and responsible utilization of microbial resources for research, education, industry, medicine, and agriculture for the betterment of human kind.” Microbial culture collections are a key component of life science research, biotechnology, and emerging global biobased economies. Representatives and users of several microbial culture collections from the United States and Europe gathered at the University of California, Davis, to discuss how collections of microorganisms can better serve users and stakeholders and to showcase existing resources available in public culture collections. PMID:26092453

  2. Quality of Service in Networks Supporting Cultural Multimedia Applications

    Science.gov (United States)

    Kanellopoulos, Dimitris N.

    2011-01-01

    Purpose: This paper aims to provide an overview of representative multimedia applications in the cultural heritage sector, as well as research results on quality of service (QoS) mechanisms in internet protocol (IP) networks that support such applications. Design/methodology/approach: The paper's approach is a literature review. Findings: Cultural…

  3. Memory in cultured cortical networks: experiment and modeling

    NARCIS (Netherlands)

    Witteveen, Tim; van Veenendaal, Tamar; le Feber, Jakob; Sergeev, A.

    The mechanism behind memory is one of the mysteries in neuroscience. Here we unravel part of the mechanism by showing that cultured neuronal networks develop an activity connectivity balance. External inputs disturb this balance and induce connectivity changes. The new connectivity is no longer

  4. Consumer culture theory (re)visits actor-network theory

    DEFF Research Database (Denmark)

    Bajde, Domen

    2013-01-01

    The vocabulary and tactics developed by actor-network theory (ANT) can shed light on several ontological and epistemological challenges faced by consumer culture theory. Rather than providing ready-made theories or methods, our translation of ANT puts forward a series of questions and propositions...

  5. NETWORK CULTURE - INTEGRAL PART OF NEW VALUES OF CIVIL SOCIETY

    Directory of Open Access Journals (Sweden)

    Vyacheslav Vladimirovich Sukhanov

    2014-06-01

    Full Text Available New technologies not only improve working conditions or communication, they are also bringing new values to  the society. This article discusses the concept of «network culture», which is now perceived by society as an integral part of values that can only exist in a civil society. We can research ( find   this kind of society in modern time period in Russia. The article analyzes the meaning of communication, how to use it, development processes in network media.  Nowadays network culture and its influence on society are almost in all spheres of state and society, as well as changes in perception of information and content generation process. Development of the Internet and Internet technologies largely set the tone for  the development of popular culture and allows you to store or to influence the national culture. Internet press today is and example which shows us, how this kind of tool can be used to influence on citizens.DOI: http://dx.doi.org/10.12731/2218-7405-2014-3-6

  6. Spreadable media: Creating value and meaning in a networked culture

    Directory of Open Access Journals (Sweden)

    Moderated by Louisa Stein

    2014-09-01

    Full Text Available Online Roundtable on Spreadable Media, by Henry Jenkins, Sam Ford, and Joshua Green, with participants Paul Booth, Kristina Busse, Melissa Click, Sam Ford, Henry Jenkins, Xiaochang Li, and Sharon Ross. Section 1 first published as the article "Spreadable Media: Creating Value and Meaning in a Networked Culture", by Louisa Stein, from Cinema Journal Volume 53 Issue 3, pp152-177. Copyright 2014 by The University of Texas Press. All rights reserved.

  7. Cultured Neural Networks: Optimization of Patterned Network Adhesiveness and Characterization of their Neural Activity

    Directory of Open Access Journals (Sweden)

    W. L. C. Rutten

    2006-01-01

    Full Text Available One type of future, improved neural interface is the “cultured probe”. It is a hybrid type of neural information transducer or prosthesis, for stimulation and/or recording of neural activity. It would consist of a microelectrode array (MEA on a planar substrate, each electrode being covered and surrounded by a local circularly confined network (“island” of cultured neurons. The main purpose of the local networks is that they act as biofriendly intermediates for collateral sprouts from the in vivo system, thus allowing for an effective and selective neuron–electrode interface. As a secondary purpose, one may envisage future information processing applications of these intermediary networks. In this paper, first, progress is shown on how substrates can be chemically modified to confine developing networks, cultured from dissociated rat cortex cells, to “islands” surrounding an electrode site. Additional coating of neurophobic, polyimide-coated substrate by triblock-copolymer coating enhances neurophilic-neurophobic adhesion contrast. Secondly, results are given on neuronal activity in patterned, unconnected and connected, circular “island” networks. For connected islands, the larger the island diameter (50, 100 or 150 μm, the more spontaneous activity is seen. Also, activity may show a very high degree of synchronization between two islands. For unconnected islands, activity may start at 22 days in vitro (DIV, which is two weeks later than in unpatterned networks.

  8. 77 FR 37730 - Culturally Significant Objects Imported for Exhibition Determinations: “Nomads and Networks: The...

    Science.gov (United States)

    2012-06-22

    ... DEPARTMENT OF STATE [Public Notice 7928] Culturally Significant Objects Imported for Exhibition Determinations: ``Nomads and Networks: The Ancient Art and Culture of Kazakhstan'' SUMMARY: Notice is hereby... objects to be included in the exhibition ``Nomads and Networks: The Ancient Art and Culture of Kazakhstan...

  9. 77 FR 7229 - Culturally Significant Objects Imported for Exhibition Determinations: “Nomads and Networks: The...

    Science.gov (United States)

    2012-02-10

    ... DEPARTMENT OF STATE [Public Notice 7794] Culturally Significant Objects Imported for Exhibition Determinations: ``Nomads and Networks: The Ancient Art and Culture of Kazakhstan'' SUMMARY: Notice is hereby... objects to be included in the exhibition ``Nomads and Networks: The Ancient Art and Culture of Kazakhstan...

  10. Epigenome profiling and editing of neocortical progenitor cells during development.

    Science.gov (United States)

    Albert, Mareike; Kalebic, Nereo; Florio, Marta; Lakshmanaperumal, Naharajan; Haffner, Christiane; Brandl, Holger; Henry, Ian; Huttner, Wieland B

    2017-09-01

    The generation of neocortical neurons from neural progenitor cells (NPCs) is primarily controlled by transcription factors binding to DNA in the context of chromatin. To understand the complex layer of regulation that orchestrates different NPC types from the same DNA sequence, epigenome maps with cell type resolution are required. Here, we present genomewide histone methylation maps for distinct neural cell populations in the developing mouse neocortex. Using different chromatin features, we identify potential novel regulators of cortical NPCs. Moreover, we identify extensive H3K27me3 changes between NPC subtypes coinciding with major developmental and cell biological transitions. Interestingly, we detect dynamic H3K27me3 changes on promoters of several crucial transcription factors, including the basal progenitor regulator Eomes We use catalytically inactive Cas9 fused with the histone methyltransferase Ezh2 to edit H3K27me3 at the Eomes locus in vivo , which results in reduced Tbr2 expression and lower basal progenitor abundance, underscoring the relevance of dynamic H3K27me3 changes during neocortex development. Taken together, we provide a rich resource of neocortical histone methylation data and outline an approach to investigate its contribution to the regulation of selected genes during neocortical development. © 2017 The Authors.

  11. Neocortical development as an evolutionary platform for intragenomic conflict

    Directory of Open Access Journals (Sweden)

    Eric eLewitus

    2013-04-01

    Full Text Available Embryonic development in mammals has evolved a platform for genomic conflict between mothers and embryos and, by extension, between maternal and paternal genomes. The evolutionary interests of the mother and embryo may be maximized through the promotion of sex-chromosome genes and imprinted alleles, resulting in the rapid evolution of postzygotic phenotypes preferential to either the maternal or paternal genome. In eutherian mammals, extraordinary in utero maternal investment in the brain, and neocortex especially, suggests that convergent evolution of an expanded mammalian neocortex along divergent lineages may be explained, in part, by parent-of-origin-linked gene expression arising from parent-offspring conflict. The influence of this conflict on neocortical development and evolution, however, has not been investigated at the genomic level. In this hypothesis and theory article, we provide preliminary evidence for positive selection in humans in the regions of two platforms of intragenomic conflict – chromosomes 15q11-q13 and X – and explore the potential relevance of cis-regulated imprinted domains to neocortical expansion in mammalian evolution. We present the hypothesis that maternal- and paternal-specific pressures on the developing neocortex compete intragenomically to influence neocortical expansion in mammalian evolution.

  12. Three-dimensional neural cultures produce networks that mimic native brain activity.

    Science.gov (United States)

    Bourke, Justin L; Quigley, Anita F; Duchi, Serena; O'Connell, Cathal D; Crook, Jeremy M; Wallace, Gordon G; Cook, Mark J; Kapsa, Robert M I

    2018-02-01

    Development of brain function is critically dependent on neuronal networks organized through three dimensions. Culture of central nervous system neurons has traditionally been limited to two dimensions, restricting growth patterns and network formation to a single plane. Here, with the use of multichannel extracellular microelectrode arrays, we demonstrate that neurons cultured in a true three-dimensional environment recapitulate native neuronal network formation and produce functional outcomes more akin to in vivo neuronal network activity. Copyright © 2017 John Wiley & Sons, Ltd.

  13. The interplay between social networks and culture: theoretically and among whales and dolphins

    OpenAIRE

    Cantor, Mauricio; Whitehead, Hal

    2013-01-01

    Culture is increasingly being understood as a driver of mammalian phenotypes. Defined as group-specific behaviour transmitted by social learning, culture is shaped by social structure. However, culture can itself affect social structure if individuals preferentially interact with others whose behaviour is similar, or cultural symbols are used to mark groups. Using network formalism, this interplay can be depicted by the coevolution of nodes and edges together with the coevolution of network t...

  14. Production and organization of neocortical interneurons

    Directory of Open Access Journals (Sweden)

    Khadeejah T Sultan

    2013-11-01

    Full Text Available Inhibitory GABA (γ-aminobutyric acid-ergic interneurons are a vital component of the neocortex responsible for shaping its output through a variety of inhibitions. Consisting of many flavors, interneuron subtypes are predominantly defined by their morphological, physiological, and neurochemical properties that help to determine their functional role within the neocortex. During development, these cells are born in the subpallium where they then tangentially migrate over long distances before being radially positioned to their final location in the cortical laminae. As development progresses into adolescence, these cells mature and form chemical and electrical connections with both glutamatergic excitatory neurons and other interneurons ultimately establishing the cortical network. The production, migration, and organization of these cells are determined by vast array of extrinsic and intrinsic factors that work in concert in order to assemble a proper functioning cortical inhibitory network. Failure of these cells to undergo these processes results in abnormal positioning and cortical function. In humans, this can bring about several neurological disorders including schizophrenia, epilepsy and autism spectrum disorders. In this article, we will review previous literature that has revealed the framework for interneuron neurogenesis and migratory behavior as well as discuss recent findings that aim to elucidate the spatial and functional organization of interneurons within the neocortex.

  15. Neocortical electrical stimulation for epilepsy : Closed-loop versus open-loop

    NARCIS (Netherlands)

    Vassileva, Albena; van Blooijs, Dorien; Leijten, Frans; Huiskamp, Geertjan

    2018-01-01

    The aim of this review is to evaluate whether open-loop or closed-loop neocortical electrical stimulation should be the preferred approach to manage seizures in intractable epilepsy. Twenty cases of open-loop neocortical stimulation with an implanted device have been reported, in 5 case studies.

  16. Animal social networks as substrate for cultural behavioural diversity.

    Science.gov (United States)

    Whitehead, Hal; Lusseau, David

    2012-02-07

    We used individual-based stochastic models to examine how social structure influences the diversity of socially learned behaviour within a non-human population. For continuous behavioural variables we modelled three forms of dyadic social learning, averaging the behavioural value of the two individuals, random transfer of information from one individual to the other, and directional transfer from the individual with highest behavioural value to the other. Learning had potential error. We also examined the transfer of categorical behaviour between individuals with random directionality and two forms of error, the adoption of a randomly chosen existing behavioural category or the innovation of a new type of behaviour. In populations without social structuring the diversity of culturally transmitted behaviour increased with learning error and population size. When the populations were structured socially either by making individuals members of permanent social units or by giving them overlapping ranges, behavioural diversity increased with network modularity under all scenarios, although the proportional increase varied considerably between continuous and categorical behaviour, with transmission mechanism, and population size. Although functions of the form e(c)¹(m)⁻(c)² + (c)³(Log(N)) predicted the mean increase in diversity with modularity (m) and population size (N), behavioural diversity could be highly unpredictable both between simulations with the same set of parameters, and within runs. Errors in social learning and social structuring generally promote behavioural diversity. Consequently, social learning may be considered to produce culture in populations whose social structure is sufficiently modular. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Artificial spatiotemporal touch inputs reveal complementary decoding in neocortical neurons.

    Science.gov (United States)

    Oddo, Calogero M; Mazzoni, Alberto; Spanne, Anton; Enander, Jonas M D; Mogensen, Hannes; Bengtsson, Fredrik; Camboni, Domenico; Micera, Silvestro; Jörntell, Henrik

    2017-04-04

    Investigations of the mechanisms of touch perception and decoding has been hampered by difficulties in achieving invariant patterns of skin sensor activation. To obtain reproducible spatiotemporal patterns of activation of sensory afferents, we used an artificial fingertip equipped with an array of neuromorphic sensors. The artificial fingertip was used to transduce real-world haptic stimuli into spatiotemporal patterns of spikes. These spike patterns were delivered to the skin afferents of the second digit of rats via an array of stimulation electrodes. Combined with low-noise intra- and extracellular recordings from neocortical neurons in vivo, this approach provided a previously inaccessible high resolution analysis of the representation of tactile information in the neocortical neuronal circuitry. The results indicate high information content in individual neurons and reveal multiple novel neuronal tactile coding features such as heterogeneous and complementary spatiotemporal input selectivity also between neighboring neurons. Such neuronal heterogeneity and complementariness can potentially support a very high decoding capacity in a limited population of neurons. Our results also indicate a potential neuroprosthetic approach to communicate with the brain at a very high resolution and provide a potential novel solution for evaluating the degree or state of neurological disease in animal models.

  18. Facilitation of neocortical presynaptic terminal development by NMDA receptor activation

    Directory of Open Access Journals (Sweden)

    Sceniak Michael P

    2012-02-01

    Full Text Available Abstract Background Neocortical circuits are established through the formation of synapses between cortical neurons, but the molecular mechanisms of synapse formation are only beginning to be understood. The mechanisms that control synaptic vesicle (SV and active zone (AZ protein assembly at developing presynaptic terminals have not yet been defined. Similarly, the role of glutamate receptor activation in control of presynaptic development remains unclear. Results Here, we use confocal imaging to demonstrate that NMDA receptor (NMDAR activation regulates accumulation of multiple SV and AZ proteins at nascent presynaptic terminals of visual cortical neurons. NMDAR-dependent regulation of presynaptic assembly occurs even at synapses that lack postsynaptic NMDARs. We also provide evidence that this control of presynaptic terminal development is independent of glia. Conclusions Based on these data, we propose a novel NMDAR-dependent mechanism for control of presynaptic terminal development in excitatory neocortical neurons. Control of presynaptic development by NMDARs could ultimately contribute to activity-dependent development of cortical receptive fields.

  19. CLASP2 Links Reelin to the Cytoskeleton during Neocortical Development.

    Science.gov (United States)

    Dillon, Gregory M; Tyler, William A; Omuro, Kerilyn C; Kambouris, John; Tyminski, Camila; Henry, Shawna; Haydar, Tarik F; Beffert, Uwe; Ho, Angela

    2017-03-22

    The Reelin signaling pathway plays a crucial role in regulating neocortical development. However, little is known about how Reelin controls the cytoskeleton during neuronal migration. Here, we identify CLASP2 as a key cytoskeletal effector in the Reelin signaling pathway. We demonstrate that CLASP2 has distinct roles during neocortical development regulating neuron production and controlling neuron migration, polarity, and morphogenesis. We found downregulation of CLASP2 in migrating neurons leads to mislocalized cells in deeper cortical layers, abnormal positioning of the centrosome-Golgi complex, and aberrant length/orientation of the leading process. We discovered that Reelin regulates several phosphorylation sites within the positively charged serine/arginine-rich region that constitute consensus GSK3β phosphorylation motifs of CLASP2. Furthermore, phosphorylation of CLASP2 regulates its interaction with the Reelin adaptor Dab1 and this association is required for CLASP2 effects on neurite extension and motility. Together, our data reveal that CLASP2 is an essential Reelin effector orchestrating cytoskeleton dynamics during brain development. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Hippocampal-neocortical functional reorganization underlies children's cognitive development.

    Science.gov (United States)

    Qin, Shaozheng; Cho, Soohyun; Chen, Tianwen; Rosenberg-Lee, Miriam; Geary, David C; Menon, Vinod

    2014-09-01

    The importance of the hippocampal system for rapid learning and memory is well recognized, but its contributions to a cardinal feature of children's cognitive development-the transition from procedure-based to memory-based problem-solving strategies-are unknown. Here we show that the hippocampal system is pivotal to this strategic transition. Longitudinal functional magnetic resonance imaging (fMRI) in 7-9-year-old children revealed that the transition from use of counting to memory-based retrieval parallels increased hippocampal and decreased prefrontal-parietal engagement during arithmetic problem solving. Longitudinal improvements in retrieval-strategy use were predicted by increased hippocampal-neocortical functional connectivity. Beyond childhood, retrieval-strategy use continued to improve through adolescence into adulthood and was associated with decreased activation but more stable interproblem representations in the hippocampus. Our findings provide insights into the dynamic role of the hippocampus in the maturation of memory-based problem solving and establish a critical link between hippocampal-neocortical reorganization and children's cognitive development.

  1. Cultural intelligence and network organizations in society: Case of Tehran neighborhood councils

    Directory of Open Access Journals (Sweden)

    Salamzadeh Yashar

    2016-01-01

    Full Text Available Network communications is one of the modern ideas in the field of organizational behavior. On the other hand, the ability to communicate with employees and understand the cultural differences between them in a multicultural environment is one of the key skills that managers and employees need them in the nowadays organizations. These skills are introduced as cultural intelligence in organizations that have ability to respond to many challenges in multicultural environments. This article was aimed to analysis the relationship between cultural intelligence and network communication. These questionnaires were distributed between 134 members at the Tehran neighborhood councils. In order to analyzing data and concluding results, SPSS, and then Pearson correlation test were used. The research was done based on structural equation modeling (SEM. The result indicated that there was significant positive relationship between cultural intelligence and network communication. Also there was significant positive relationship between each dimension of cultural intelligence and network communication. Findings show that cultural intelligence is a basic factor in network communication and confirm the main hypothesis of this study which represents the existence of a positive and meaningful relation between cultural intelligence and network communication. Furthermore, the results show that considering this kind of intelligence, especially in network organizations which has a high ethnic and cultural variety, could be very useful for improve employees and managers communications.

  2. Neocortical inhibitory activities and long-range afferents contribute to the synchronous onset of silent states of the neocortical slow oscillation.

    Science.gov (United States)

    Lemieux, Maxime; Chauvette, Sylvain; Timofeev, Igor

    2015-02-01

    During slow-wave sleep, neurons of the thalamocortical network are engaged in a slow oscillation (<1 Hz), which consists of an alternation between the active and the silent states. Several studies have provided insights on the transition from the silent, which are essentially periods of disfacilitation, to the active states. However, the conditions leading to the synchronous onset of the silent state remain elusive. We hypothesized that a synchronous input to local inhibitory neurons could contribute to the transition to the silent state in the cat suprasylvian gyrus during natural sleep and under ketamine-xylazine anesthesia. After partial and complete deafferentation of the cortex, we found that the silent state onset was more variable among remote sites. We found that the transition to the silent state was preceded by a reduction in excitatory postsynaptic potentials and firing probability in cortical neurons. We tested the impact of chloride-mediated inhibition in the silent-state onset. We uncovered a long-duration (100-300 ms) inhibitory barrage occurring about 250 ms before the silent state onset in 3-6% of neurons during anesthesia and in 12-15% of cases during natural sleep. These inhibitory activities caused a decrease in cortical firing that reduced the excitatory drive in the neocortical network. That chain reaction of disfacilitation ends up on the silent state. Electrical stimuli could trigger a network silent state with a maximal efficacy in deep cortical layers. We conclude that long-range afferents to the neocortex and chloride-mediated inhibition play a role in the initiation of the silent state. Copyright © 2015 the American Physiological Society.

  3. Understanding and Influencing Teaching and Learning Cultures at University: A Network Approach

    Science.gov (United States)

    Roxa, Torgny; Martensson, Katarina; Alveteg, Mattias

    2011-01-01

    Academic cultures might be perceived as conservative, at least in terms of development of teaching and learning. Through a lens of network theory this conceptual article analyses the pattern of pathways in which culture is constructed through negotiation of meaning. The perspective contributes to an understanding of culture construction and…

  4. Structural and Functional Alterations in Neocortical Circuits after Mild Traumatic Brain Injury

    Science.gov (United States)

    Vascak, Michal

    National concern over traumatic brain injury (TBI) is growing rapidly. Recent focus is on mild TBI (mTBI), which is the most prevalent injury level in both civilian and military demographics. A preeminent sequelae of mTBI is cognitive network disruption. Advanced neuroimaging of mTBI victims supports this premise, revealing alterations in activation and structure-function of excitatory and inhibitory neuronal systems, which are essential for network processing. However, clinical neuroimaging cannot resolve the cellular and molecular substrates underlying such changes. Therefore, to understand the full scope of mTBI-induced alterations it is necessary to study cortical networks on the microscopic level, where neurons form local networks that are the fundamental computational modules supporting cognition. Recently, in a well-controlled animal model of mTBI, we demonstrated in the excitatory pyramidal neuron system, isolated diffuse axonal injury (DAI), in concert with electrophysiological abnormalities in nearby intact (non-DAI) neurons. These findings were consistent with altered axon initial segment (AIS) intrinsic activity functionally associated with structural plasticity, and/or disturbances in extrinsic systems related to parvalbumin (PV)-expressing interneurons that form GABAergic synapses along the pyramidal neuron perisomatic/AIS domains. The AIS and perisomatic GABAergic synapses are domains critical for regulating neuronal activity and E-I balance. In this dissertation, we focus on the neocortical excitatory pyramidal neuron/inhibitory PV+ interneuron local network following mTBI. Our central hypothesis is that mTBI disrupts neuronal network structure and function causing imbalance of excitatory and inhibitory systems. To address this hypothesis we exploited transgenic and cre/lox mouse models of mTBI, employing approaches that couple state-of-the-art bioimaging with electrophysiology to determine the structuralfunctional alterations of excitatory and

  5. Exploring Educational and Cultural Adaptation through Social Networking Sites

    Science.gov (United States)

    Ryan, Sherry D.; Magro, Michael J.; Sharp, Jason H.

    2011-01-01

    Social networking sites have seen tremendous growth and are widely used around the world. Nevertheless, the use of social networking sites in educational contexts is an under explored area. This paper uses a qualitative methodology, autoethnography, to investigate how social networking sites, specifically Facebook[TM], can help first semester…

  6. Social Networking Sites Use and Cross Cultural Adaptation of Muslim Indonesian Students in Australian Universities: Valuing Cultural Diversity

    OpenAIRE

    Nuraryo, Imam

    2016-01-01

    Muslim Asian students have diverse specific needs when undertaking education in western country universities. Many international students use social networking sites as media for distance communication and helping in their adjustment.This study attempts to investigate the impact of using new social networking sites on the cross cultural adaptation process. Qualitative methodology was used for the study. Individual in-depth interviews were conducted for data collection. The study investigates ...

  7. Cultural Routes and Networks of Knowledge: the Identity and Promotion of Cultural Heritage. The Case Study of Piedmont

    OpenAIRE

    Silvia Beltramo

    2013-01-01

    The European project called “PER VIAM Pilgrims’ Routes In Action”, funded by the European Commission in 2012, is a significant opportunity of cultural and economic development for the whole Europe and also for the territory of Piedmont Region. The certainty of the need for transnational cooperation, which should create a network amongst the different territories in a perspective of working together and exchange of traveling, economic and cultural experiences – as well as best practices - nowa...

  8. Identification of neuronal network properties from the spectral analysis of calcium imaging signals in neuronal cultures.

    Science.gov (United States)

    Tibau, Elisenda; Valencia, Miguel; Soriano, Jordi

    2013-01-01

    Neuronal networks in vitro are prominent systems to study the development of connections in living neuronal networks and the interplay between connectivity, activity and function. These cultured networks show a rich spontaneous activity that evolves concurrently with the connectivity of the underlying network. In this work we monitor the development of neuronal cultures, and record their activity using calcium fluorescence imaging. We use spectral analysis to characterize global dynamical and structural traits of the neuronal cultures. We first observe that the power spectrum can be used as a signature of the state of the network, for instance when inhibition is active or silent, as well as a measure of the network's connectivity strength. Second, the power spectrum identifies prominent developmental changes in the network such as GABAA switch. And third, the analysis of the spatial distribution of the spectral density, in experiments with a controlled disintegration of the network through CNQX, an AMPA-glutamate receptor antagonist in excitatory neurons, reveals the existence of communities of strongly connected, highly active neurons that display synchronous oscillations. Our work illustrates the interest of spectral analysis for the study of in vitro networks, and its potential use as a network-state indicator, for instance to compare healthy and diseased neuronal networks.

  9. Mild prenatal protein malnutrition increases alpha2C-adrenoceptor density in the cerebral cortex during postnatal life and impairs neocortical long-term potentiation and visuo-spatial performance in rats.

    Science.gov (United States)

    Soto-Moyano, Rubén; Valladares, Luis; Sierralta, Walter; Pérez, Hernán; Mondaca, Mauricio; Fernández, Victor; Burgos, Héctor; Hernández, Alejandro

    2005-06-01

    Mild reduction in the protein content of the mother's diet from 25 to 8% casein, calorically compensated by carbohydrates, does not alter body and brain weights of rat pups at birth, but leads to significant enhancements in the concentration and release of cortical noradrenaline during early postnatal life. Since central noradrenaline and some of its receptors are critically involved in long-term potentiation (LTP) and memory formation, this study evaluated the effect of mild prenatal protein malnutrition on the alpha2C-adrenoceptor density in the frontal and occipital cortices, induction of LTP in the same cortical regions and the visuo-spatial memory. Pups born from rats fed a 25% casein diet throughout pregnancy served as controls. At day 8 of postnatal age, prenatally malnourished rats showed a threefold increase in neocortical alpha2C-adrenoceptor density. At 60 days-of-age, alpha2C-adrenoceptor density was still elevated in the neocortex, and the animals were unable to maintain neocortical LTP and presented lower visuo-spatial memory performance. Results suggest that overexpression of neocortical alpha2C-adrenoceptors during postnatal life, subsequent to mild prenatal protein malnutrition, could functionally affect the synaptic networks subserving neocortical LTP and visuo-spatial memory formation.

  10. Organizational Culture and Firms’ Internationalization, Innovativeness and Networking Behaviour: Hofstede Approach

    OpenAIRE

    Maja Szymura-Tyc; Michał Kucia

    2016-01-01

    Objective: The objective of this paper is to describe the features of firms’ organizational culture within four of Hofstede’s national culture dimensions and their potential relationships with internationalization, innovativeness and networking behaviour of firms. Research Design & Methods: This explorative quantitative research refers to results of an earlier study on internationalization, innovativeness and networking of firms in Poland. Descriptive statistics are used to depict the...

  11. Safety culture and subcontractor network governance in a complex safety critical project

    International Nuclear Information System (INIS)

    Oedewald, Pia; Gotcheva, Nadezhda

    2015-01-01

    In safety critical industries many activities are currently carried out by subcontractor networks. Nevertheless, there are few studies where the core dimensions of resilience would have been studied in safety critical network activities. This paper claims that engineering resilience into a system is largely about steering the development of culture of the system towards better ability to anticipate, monitor, respond and learn. Thus, safety culture literature has relevance in resilience engineering field. This paper analyzes practical and theoretical challenges in applying the concept of safety culture in a complex, dynamic network of subcontractors involved in the construction of a new nuclear power plant in Finland, Olkiluoto 3. The concept of safety culture is in focus since it is widely used in nuclear industry and bridges the scientific and practical interests. This paper approaches subcontractor networks as complex systems. However, the management model of the Olkiluoto 3 project is to a large degree a traditional top-down hierarchy, which creates a mismatch between the management approach and the characteristics of the system to be managed. New insights were drawn from network governance studies. - Highlights: • We studied a relevant topical subject safety culture in nuclear new build project. • We integrated safety science challenges and network governance studies. • We produced practicable insights in managing safety of subcontractor networks

  12. Culture, agency and power: Theoretical reflections on informal economic networks and political process

    OpenAIRE

    Meagher, Kate

    2009-01-01

    Do network theory really offer a suitable concept for the theorization of informal processes of economic regulation and institutional change? This working paper challenges both essentialist and skeptical attitudes to networks through an examination of the positive and negative effects of network governance in contemporary societies in a range of regional contexts. The analysis focuses on three broad principles of non-state organization - culture, agency and power - and their role in shaping p...

  13. A Cross-Cultural Comparison of Korean and American Social Network Sites: Exploring Cultural Differences in Social Relationships and Self-Presentation

    Science.gov (United States)

    Cho, Seong Eun

    2010-01-01

    National culture is being challenged as societies evolve from their homogeneous origins. The theoretical base of this study uses two cultural dimensions, individualism-collectivism (Hofstede, 2001) and high-and low-context cultures (Hall, 1976), to unpack the effects of national culture on social network sites (SNSs). This study explores cultural…

  14. Network Events on Multiple Space and Time Scales in Cultured Neural Networks and in a Stochastic Rate Model.

    Directory of Open Access Journals (Sweden)

    Guido Gigante

    2015-11-01

    Full Text Available Cortical networks, in-vitro as well as in-vivo, can spontaneously generate a variety of collective dynamical events such as network spikes, UP and DOWN states, global oscillations, and avalanches. Though each of them has been variously recognized in previous works as expression of the excitability of the cortical tissue and the associated nonlinear dynamics, a unified picture of the determinant factors (dynamical and architectural is desirable and not yet available. Progress has also been partially hindered by the use of a variety of statistical measures to define the network events of interest. We propose here a common probabilistic definition of network events that, applied to the firing activity of cultured neural networks, highlights the co-occurrence of network spikes, power-law distributed avalanches, and exponentially distributed 'quasi-orbits', which offer a third type of collective behavior. A rate model, including synaptic excitation and inhibition with no imposed topology, synaptic short-term depression, and finite-size noise, accounts for all these different, coexisting phenomena. We find that their emergence is largely regulated by the proximity to an oscillatory instability of the dynamics, where the non-linear excitable behavior leads to a self-amplification of activity fluctuations over a wide range of scales in space and time. In this sense, the cultured network dynamics is compatible with an excitation-inhibition balance corresponding to a slightly sub-critical regime. Finally, we propose and test a method to infer the characteristic time of the fatigue process, from the observed time course of the network's firing rate. Unlike the model, possessing a single fatigue mechanism, the cultured network appears to show multiple time scales, signalling the possible coexistence of different fatigue mechanisms.

  15. Social Network Culture Needs the Lens of Critical Trust Research

    OpenAIRE

    Dwyer , Natasha; Marsh , Stephen

    2015-01-01

    Part 2: Full Papers; International audience; Trust is essential to the success of the social networks that are aggregating and applying masses of information about us. In this position paper, we argue that a critical approach to exploring trust and social networks is required; this entails genuinely working in the interests of users and acknowledging the power relations and wider social context of this form of technology that is impacting more and more of our everyday life. Without a critical...

  16. The interplay between social networks and culture: theoretically and among whales and dolphins.

    Science.gov (United States)

    Cantor, Mauricio; Whitehead, Hal

    2013-05-19

    Culture is increasingly being understood as a driver of mammalian phenotypes. Defined as group-specific behaviour transmitted by social learning, culture is shaped by social structure. However, culture can itself affect social structure if individuals preferentially interact with others whose behaviour is similar, or cultural symbols are used to mark groups. Using network formalism, this interplay can be depicted by the coevolution of nodes and edges together with the coevolution of network topology and transmission patterns. We review attempts to model the links between the spread, persistence and diversity of culture and the network topology of non-human societies. We illustrate these processes using cetaceans. The spread of socially learned begging behaviour within a population of bottlenose dolphins followed the topology of the social network, as did the evolution of the song of the humpback whale between breeding areas. In three bottlenose dolphin populations, individuals preferentially associated with animals using the same socially learned foraging behaviour. Homogeneous behaviour within the tight, nearly permanent social structures of the large matrilineal whales seems to result from transmission bias, with cultural symbols marking social structures. We recommend the integration of studies of culture and society in species for which social learning is an important determinant of behaviour.

  17. Persistent schema-dependent hippocampal-neocortical connectivity during memory encoding and postencoding rest in humans.

    Science.gov (United States)

    van Kesteren, Marlieke T R; Fernández, Guillén; Norris, David G; Hermans, Erno J

    2010-04-20

    The hippocampus is thought to promote gradual incorporation of novel information into long-term memory by binding, reactivating, and strengthening distributed cortical-cortical connections. Recent studies implicate a key role in this process for hippocampally driven crosstalk with the (ventro)medial prefrontal cortex (vmPFC), which is proposed to become a central node in such representational networks over time. The existence of a relevant prior associative network, or schema, may moreover facilitate this process. Thus, hippocampal-vmPFC crosstalk may support integration of new memories, particularly in the absence of a relevant prior schema. To address this issue, we used functional magnetic resonance imaging (fMRI) and prior schema manipulation to track hippocampal-vmPFC connectivity during encoding and postencoding rest. We manipulated prior schema knowledge by exposing 30 participants to the first part of a movie that was temporally scrambled for 15 participants. The next day, participants underwent fMRI while encoding the movie's final 15 min in original order and, subsequently, while resting. Schema knowledge and item recognition performance show that prior schema was successfully and selectively manipulated. Intersubject synchronization (ISS) and interregional partial correlation analyses furthermore show that stronger prior schema was associated with more vmPFC ISS and less hippocampal-vmPFC interregional connectivity during encoding. Notably, this connectivity pattern persisted during postencoding rest. These findings suggest that additional crosstalk between hippocampus and vmPFC is required to compensate for difficulty integrating novel information during encoding and provide tentative support for the notion that functionally relevant hippocampal-neocortical crosstalk persists during off-line periods after learning.

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

    Directory of Open Access Journals (Sweden)

    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

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

    NARCIS (Netherlands)

    Rutten, Wim; van Pelt, 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

  20. The co-evolution of cultures, social network communities, and agent locations in an extension of Axelrod’s model of cultural dissemination

    Science.gov (United States)

    Pfau, Jens; Kirley, Michael; Kashima, Yoshihisa

    2013-01-01

    We introduce a variant of the Axelrod model of cultural dissemination in which agents change their physical locations, social links, and cultures. Numerical simulations are used to investigate the evolution of social network communities and the cultural diversity within and between these communities. An analysis of the simulation results shows that an initial peak in the cultural diversity within network communities is evident before agents segregate into a final configuration of culturally homogeneous communities. Larger long-range interaction probabilities facilitate the initial emergence of culturally diverse network communities, which leads to a more pronounced initial peak in cultural diversity within communities. At equilibrium, the number of communities, and hence cultures, increases when the initial cultural diversity increases. However, the number of communities decreases when the lattice size or population density increases. A phase transition between two regimes of initial cultural diversity is evident. For initial diversities below a critical value, a single network community and culture emerges that dominates the population. For initial diversities above the critical value, multiple culturally homogeneous communities emerge. The critical value of initial diversity at which this transition occurs increases with increasing lattice size and population density and generally with increasing absolute population size. We conclude that larger initial diversities promote cultural heterogenization, while larger lattice sizes, population densities, and in fact absolute population sizes promote homogenization.

  1. Effect of seizure on hippocampus in mesial temporal lobe epilepsy and neocortical epilepsy: an MRS study

    International Nuclear Information System (INIS)

    Lee, S.K.; Kim, D.W.; Kim, K.K.; Chung, C.K.; Song, I.C.; Chang, K.H.

    2005-01-01

    This study was performed to evaluate the effect of seizures on the bilateral hippocampus in mesial temporal lobe epilepsy (mTLE) and neocortical epilepsy by single voxel proton magnetic resonance spectroscopy (MRS). Forty-one patients with mTLE having unilateral hippocampal sclerosis and 43 patients with a neocortical epilepsy who underwent subsequent epilepsy surgery were recruited. Ninety-five percent confidence intervals of N-acetyl aspartate/choline (NAA/Cho) and NAA/creatine (NAA/Cr) ratios in 20 healthy control subjects were used as threshold values to determine abnormal NAA/Cho and NAA/Cr. NAA/Cho and NAA/Cr were significantly lower in the ipsilateral hippocampus of mTLE and neocortical epilepsy. Using asymmetry indices for patients with bilaterally abnormal ratios of NAA/Cho and NAA/Cr in addition to using unilateral abnormal ratio, the seizure focus was correctly lateralized in 65.9% of patients with mTLE and 48.8% of neocortical epilepsy patients. Bilateral NAA/Cho abnormality was significantly related to a poor surgical outcome in mTLE. No significant relationship was found between the results of NAA/Cho or NAA/Cr and surgical outcome in neocortical epilepsy. The mean contralateral NAA/Cr ratio of the hippocampus in mTLE was significantly lower in patients with a history of secondary generalized tonic-clonic seizure (SGTCS) than in those without. (orig.)

  2. Effect of seizure on hippocampus in mesial temporal lobe epilepsy and neocortical epilepsy: an MRS study

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.K.; Kim, D.W.; Kim, K.K. [Seoul National University College of Medicine, Seoul National University Hospital, Department of Neurology, Chongno ku, Seoul (Korea); Chung, C.K. [Seoul National University College of Medicine, Seoul National University Hospital, Department of Neurosurgery, Chongno ku, Seoul (Korea); Song, I.C.; Chang, K.H. [Seoul National University College of Medicine, Seoul National University Hospital, Department of Radiology, Chongno ku, Seoul (Korea)

    2005-12-01

    This study was performed to evaluate the effect of seizures on the bilateral hippocampus in mesial temporal lobe epilepsy (mTLE) and neocortical epilepsy by single voxel proton magnetic resonance spectroscopy (MRS). Forty-one patients with mTLE having unilateral hippocampal sclerosis and 43 patients with a neocortical epilepsy who underwent subsequent epilepsy surgery were recruited. Ninety-five percent confidence intervals of N-acetyl aspartate/choline (NAA/Cho) and NAA/creatine (NAA/Cr) ratios in 20 healthy control subjects were used as threshold values to determine abnormal NAA/Cho and NAA/Cr. NAA/Cho and NAA/Cr were significantly lower in the ipsilateral hippocampus of mTLE and neocortical epilepsy. Using asymmetry indices for patients with bilaterally abnormal ratios of NAA/Cho and NAA/Cr in addition to using unilateral abnormal ratio, the seizure focus was correctly lateralized in 65.9% of patients with mTLE and 48.8% of neocortical epilepsy patients. Bilateral NAA/Cho abnormality was significantly related to a poor surgical outcome in mTLE. No significant relationship was found between the results of NAA/Cho or NAA/Cr and surgical outcome in neocortical epilepsy. The mean contralateral NAA/Cr ratio of the hippocampus in mTLE was significantly lower in patients with a history of secondary generalized tonic-clonic seizure (SGTCS) than in those without. (orig.)

  3. Are the users of social networking sites homogeneous? A cross-cultural study.

    Science.gov (United States)

    Alarcón-Del-Amo, María-Del-Carmen; Gómez-Borja, Miguel-Ángel; Lorenzo-Romero, Carlota

    2015-01-01

    The growing use of Social Networking Sites (SNS) around the world has made it necessary to understand individuals' behaviors within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain), a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviors in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers.

  4. Are the users of social networking sites homogeneous? A cross-cultural study

    Science.gov (United States)

    Alarcón-del-Amo, María-del-Carmen; Gómez-Borja, Miguel-Ángel; Lorenzo-Romero, Carlota

    2015-01-01

    The growing use of Social Networking Sites (SNS) around the world has made it necessary to understand individuals' behaviors within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain), a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviors in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers. PMID:26321971

  5. Are the users of Social Networking Sites homogeneous? A cross-cultural study

    Directory of Open Access Journals (Sweden)

    MARÍA-DEL-CARMEN eALARCÓN-DEL-AMO

    2015-08-01

    Full Text Available The growing use of Social Networking Sites (SNS around the world has made it necessary to understand individuals’ behaviours within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain, a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviours in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers.

  6. Ethanol affects network activity in cultured rat hippocampus: mediation by potassium channels.

    Directory of Open Access Journals (Sweden)

    Eduard Korkotian

    Full Text Available The effects of ethanol on neuronal network activity were studied in dissociated cultures of rat hippocampus. Exposure to low (0.25-0.5% ethanol concentrations caused an increase in synchronized network spikes, and a decrease in the duration of individual spikes. Ethanol also caused an increase in rate of miniature spontaneous excitatory postsynaptic currents. Higher concentrations of ethanol eliminated network spikes. These effects were reversible upon wash. The effects of the high, but not the low ethanol were blocked by the GABA antagonist bicuculline. The enhancing action of low ethanol was blocked by apamin, an SK potassium channel antagonist, and mimicked by 1-EBIO, an SK channel opener. It is proposed that in cultured hippocampal networks low concentration of ethanol is associated with SK channel activity, rather than the GABAergic receptor.

  7. THE PREPARATION OF A SPECIALIST IN NETWORKING CULTURAL-EDUCATIONAL SPACE OF UNIVERSITY

    Directory of Open Access Journals (Sweden)

    Zinaida Kekeeva

    2015-12-01

    Full Text Available The article deals with specialist preparation problems in networking cultural-educational space of the University. The authors consider the role of networking technologies in quality improvement of educational services in the conditions of the international cooperation. They also substantiate the process of entering the future experts in the working environment, the formation of their professional and personal competencies. The article reveals priority areas of training new generation specialists in the cultural and educational space of the university taking into account modern educational trends in the world.

  8. A combined Bodian-Nissl stain for improved network analysis in neuronal cell culture.

    Science.gov (United States)

    Hightower, M; Gross, G W

    1985-11-01

    Bodian and Nissl procedures were combined to stain dissociated mouse spinal cord cells cultured on coverslips. The Bodian technique stains fine neuronal processes in great detail as well as an intracellular fibrillar network concentrated around the nucleus and in proximal neurites. The Nissl stain clearly delimits neuronal cytoplasm in somata and in large dendrites. A combination of these techniques allows the simultaneous depiction of neuronal perikarya and all afferent and efferent processes. Costaining with little background staining by either procedure suggests high specificity for neurons. This procedure could be exploited for routine network analysis of cultured neurons.

  9. Networking and cultural differences in Human Resource Management: The Case of Kazakhstan

    OpenAIRE

    Altynbekov, Mardan

    2014-01-01

    The new emerging markets are becoming significant players in global market in recent decade. This study follows current pace in employing institutional theory to explore the specific pressures and factors makes networking essential in Human Resource Management in different countries. The study is a detailed qualitative analysis of networking and cultural differences in Kazakhstan, a country with very different value and government structure. Contrary to simplistic expectations, Kazakhstan sho...

  10. Spectroscopic evidence of hippocampal abnormalities in neocortical epilepsy

    Science.gov (United States)

    Mueller, S. G.; Laxer, K. D.; Cashdollar, N.; Lopez, R. C.; Weiner, M. W.

    2009-01-01

    Lesional neocortical epilepsy (NE) can be associated with hippocampal sclerosis or hippocampal spectroscopic abnormalities without atrophy (dual pathology). In this study, magnetic resonance spectroscopic imaging (MRSI) was used to determine the frequency of hippocampal damage/dysfunction in NE with and without structural lesion. Sixteen patients with NE [seven temporal NE (NE-T), nine extratemporal (NE-ET)] and 16 controls were studied with a 2D MRSI sequence (Repetition time/echo time (TR/TE) = 1800/135 ms) covering both hippocampi. Seven NE patients had MR visible lesions (NE-Les), nine had normal MRI (NE-no). In each hippocampus, 12 voxels were uniformly selected. In controls, mean (± SD) NAA/(Cr + Cho) values for each voxel were calculated and voxels with NAA/(Cr + Cho) ≤ (mean in controls – 2SD in controls) were defined as ‘pathological’ in patients. Eight of 16 NE patients had at least two ‘pathological’ voxel (mean 2.5, range 2–5) in one hippocampus. Four were NE-Les and four NE-no. Three (43%) NE-T patients, had evidence for hippocampal damage/dysfunction and five (56%) had NE-ET. The ipsilateral hippocampus was affected in six of eight NE patients. Evidence for unilateral hippocampal damage/dysfunction was demonstrated in 50% of the NE patients. The type of NE, i.e. NE-Les or NE-no, NE-T or NE-ET, had no influence on the occurrence of hippocampal damage/dysfunction. PMID:16618342

  11. Primary cellular meningeal defects cause neocortical dysplasia and dyslamination

    Science.gov (United States)

    Hecht, Jonathan H.; Siegenthaler, Julie A.; Patterson, Katelin P.; Pleasure, Samuel J.

    2010-01-01

    Objective Cortical malformations are important causes of neurological morbidity, but in many cases their etiology is poorly understood. Mice with Foxc1 mutations have cellular defects in meningeal development. We use hypomorphic and null alleles of Foxc1 to study the effect of meningeal defects on neocortical organization. Methods Embryos with loss of Foxc1 activity were generated using the hypomorphic Foxc1hith allele and the null Foxc1lacZ allele. Immunohistologic analysis was used to assess cerebral basement membrane integrity, marginal zone heterotopia formation, neuronal overmigration, meningeal defects, and changes in basement membrane composition. Dysplasia severity was quantified using two measures. Results Cortical dysplasia resembling cobblestone cortex, with basement membrane breakdown and lamination defects, is seen in Foxc1 mutants. As Foxc1 activity was reduced, abnormalities in basement membrane integrity, heterotopia formation, neuronal overmigration, and meningeal development appeared earlier in gestation and were more severe. Surprisingly, the basement membrane appeared intact at early stages of development in the face of severe deficits in meningeal development. Prominent defects in basement membrane integrity appeared as development proceeded. Molecular analysis of basement membrane laminin subunits demonstrated that loss of the meninges led to changes in basement membrane composition. Interpretation Cortical dysplasia can be caused by cellular defects in the meninges. The meninges are not required for basement membrane establishment but are needed for remodeling as the brain expands. Specific changes in basement membrane composition may contribute to subsequent breakdown. Our study raises the possibility that primary meningeal defects may cortical dysplasia in some cases. PMID:20976766

  12. Growth dynamics explain the development of spatiotemporal burst activity of young cultured neuronal networks in detail.

    Directory of Open Access Journals (Sweden)

    Taras A Gritsun

    Full Text Available A typical property of isolated cultured neuronal networks of dissociated rat cortical cells is synchronized spiking, called bursting, starting about one week after plating, when the dissociated cells have sufficiently sent out their neurites and formed enough synaptic connections. This paper is the third in a series of three on simulation models of cultured networks. Our two previous studies [26], [27] have shown that random recurrent network activity models generate intra- and inter-bursting patterns similar to experimental data. The networks were noise or pacemaker-driven and had Izhikevich-neuronal elements with only short-term plastic (STP synapses (so, no long-term potentiation, LTP, or depression, LTD, was included. However, elevated pre-phases (burst leaders and after-phases of burst main shapes, that usually arise during the development of the network, were not yet simulated in sufficient detail. This lack of detail may be due to the fact that the random models completely missed network topology .and a growth model. Therefore, the present paper adds, for the first time, a growth model to the activity model, to give the network a time dependent topology and to explain burst shapes in more detail. Again, without LTP or LTD mechanisms. The integrated growth-activity model yielded realistic bursting patterns. The automatic adjustment of various mutually interdependent network parameters is one of the major advantages of our current approach. Spatio-temporal bursting activity was validated against experiment. Depending on network size, wave reverberation mechanisms were seen along the network boundaries, which may explain the generation of phases of elevated firing before and after the main phase of the burst shape.In summary, the results show that adding topology and growth explain burst shapes in great detail and suggest that young networks still lack/do not need LTP or LTD mechanisms.

  13. Inferring cultural regions from correlation networks of given baby names

    Science.gov (United States)

    Pomorski, Mateusz; Krawczyk, Małgorzata J.; Kułakowski, Krzysztof; Kwapień, Jarosław; Ausloos, Marcel

    2016-03-01

    We report investigations on the statistical characteristics of the baby names given between 1910 and 2010 in the United States of America. For each year, the 100 most frequent names in the USA are sorted out. For these names, the correlations between the names profiles are calculated for all pairs of states (minus Hawaii and Alaska). The correlations are used to form a weighted network which is found to vary mildly in time. In fact, the structure of communities in the network remains quite stable till about 1980. The goal is that the calculated structure approximately reproduces the usually accepted geopolitical regions: the Northeast, the South, and the "Midwest + West" as the third one. Furthermore, the dataset reveals that the name distribution satisfies the Zipf law, separately for each state and each year, i.e. the name frequency f ∝r-α, where r is the name rank. Between 1920 and 1980, the exponent α is the largest one for the set of states classified as 'the South', but the smallest one for the set of states classified as "Midwest + West". Our interpretation is that the pool of selected names was quite narrow in the Southern states. The data is compared with some related statistics of names in Belgium, a country also with different regions, but having quite a different scale than the USA. There, the Zipf exponent is low for young people and for the Brussels citizens.

  14. The role of “network of cities” in construction of global urban culture

    OpenAIRE

    Baycan-Levent, Tüzin; Kundak, Seda; Gülümser, Aliye Ahu

    2004-01-01

    The globalization process has led to an increased interaction between cities and to a new urban system/network in which they need to be competitive and complementary at the same time. “Network of cities”, such as World Cities, Eurocities or Sister Cities are among the well known examples of interaction and cooperation of the cities at the regional and global level. The cities of different regions and countries tend to share their experiences and their cultures within these networks in order t...

  15. The Effect of Facebook Social Network on Cultural Identity of Youth in Isfahan

    Directory of Open Access Journals (Sweden)

    Samad Alipour

    2014-06-01

    Full Text Available By expanding the access to the Internet and the Internet social networks and increasing use which the youth represents of different types of issues and the content of these modern media, the cultural identity has transformed into one of the main concerns related to social coherence and national unity. Therefore, the present study investigates the relationship between the presence and interaction in Facebook social network and the youth's cultural identity. The main question of this study is what influence using Facebook has on cultural identity of users? Is Facebook as one of the tools of globalization attenuator of cultural identity? The present study is in the form of a survey one and is conducted using the method ofvolunteer and available sampling and employing the internet researcher-made questionnaire by focusing Giddens' Cultivation and Strucration theories. The population of the present study includes young users of Facebook in Isfahan in 2012 and the sample is equal 424 participants. The results of the present study indicate that there is a significant and reverse correlation between the length of membership, users' amount of se and participation and activities in Facebook and their cultural identities and also there is a significant and positive correlation between considering Facebook contents as real and users' cultural identities. It means that the more the length of membership is, the more the users' amount of use and participation and activity in Facebook and the weaker users' cultural identities.

  16. Young Diplomats' Socialization to the Networked Professional Cultures of Their Workplace Communities

    Science.gov (United States)

    Hytönen, Kaisa; Hakkarainen, Kai; Palonen, Tuire

    2011-01-01

    The purpose of the present investigation was to examine young diplomats' socialization to the professional expert culture of the Ministry for Foreign Affairs of Finland over a six-month on-job training period, as part of their preparation for service in the diplomatic corps. Using social network analysis, we analyzed departments' internal social…

  17. Phase-dependent effects of stimuli locked to oscillatory activity in cultured cortical networks

    NARCIS (Netherlands)

    Stegenga, J.; le Feber, Jakob; Marani, Enrico; Rutten, Wim

    The archetypal activity pattern in cultures of dissociated neurons is spontaneous network-wide bursting. Bursts may interfere with controlled activation of synaptic plasticity, but can be suppressed by the application of stimuli at a sufficient rate. We sinusoidally modulated (4 Hz) the pulse rate

  18. Repeated Stimulation of Cultured Networks of Rat Cortical Neurons Induces Parallel Memory Traces

    Science.gov (United States)

    le Feber, Joost; Witteveen, Tim; van Veenendaal, Tamar M.; Dijkstra, Jelle

    2015-01-01

    During systems consolidation, memories are spontaneously replayed favoring information transfer from hippocampus to neocortex. However, at present no empirically supported mechanism to accomplish a transfer of memory from hippocampal to extra-hippocampal sites has been offered. We used cultured neuronal networks on multielectrode arrays and…

  19. A methodology for a quantitative assessment of safety culture in NPPs based on Bayesian networks

    International Nuclear Information System (INIS)

    Kim, Young Gab; Lee, Seung Min; Seong, Poong Hyun

    2017-01-01

    Highlights: • A safety culture framework and a quantitative methodology to assess safety culture were proposed. • The relation among Norm system, Safety Management System and worker's awareness was established. • Safety culture probability at NPPs was updated by collecting actual organizational data. • Vulnerable areas and the relationship between safety culture and human error were confirmed. - Abstract: For a long time, safety has been recognized as a top priority in high-reliability industries such as aviation and nuclear power plants (NPPs). Establishing a safety culture requires a number of actions to enhance safety, one of which is changing the safety culture awareness of workers. The concept of safety culture in the nuclear power domain was established in the International Atomic Energy Agency (IAEA) safety series, wherein the importance of employee attitudes for maintaining organizational safety was emphasized. Safety culture assessment is a critical step in the process of enhancing safety culture. In this respect, assessment is focused on measuring the level of safety culture in an organization, and improving any weakness in the organization. However, many continue to think that the concept of safety culture is abstract and unclear. In addition, the results of safety culture assessments are mostly subjective and qualitative. Given the current situation, this paper suggests a quantitative methodology for safety culture assessments based on a Bayesian network. A proposed safety culture framework for NPPs would include the following: (1) a norm system, (2) a safety management system, (3) safety culture awareness of worker, and (4) Worker behavior. The level of safety culture awareness of workers at NPPs was reasoned through the proposed methodology. Then, areas of the organization that were vulnerable in terms of safety culture were derived by analyzing observational evidence. We also confirmed that the frequency of events involving human error

  20. Collectivism culture, HIV stigma and social network support in Anhui, China: a path analytic model.

    Science.gov (United States)

    Zang, Chunpeng; Guida, Jennifer; Sun, Yehuan; Liu, Hongjie

    2014-08-01

    HIV stigma is rooted in culture and, therefore, it is essential to investigate it within the context of culture. The objective of this study was to examine the interrelationships among individualism-collectivism, HIV stigma, and social network support. A social network study was conducted among 118 people living with HIVAIDS in China, who were infected by commercial plasma donation, a nonstigmatized behavior. The Individualism-Collectivism Interpersonal Assessment Inventory (ICIAI) was used to measure cultural norms and values in the context of three social groups, family members, friends, and neighbors. Path analyses revealed (1) a higher level of family ICIAI was significantly associated with a higher level of HIV self-stigma (β=0.32); (2) a higher level of friend ICIAI was associated with a lower level of self-stigma (β=-035); (3) neighbor ICIAI was associated with public stigma (β=-0.61); (4) self-stigman was associated with social support from neighbors (β=-0.27); and (5) public stigma was associated with social support from neighbors (β=-0.24). This study documents that HIV stigma may mediate the relationship between collectivist culture and social network support, providing an empirical basis for interventions to include aspects of culture into HIV intervention strategies.

  1. Dearfield Dream Project: Developing an Interdisciplinary Historical/Cultural Research Network

    Directory of Open Access Journals (Sweden)

    Robert Brunswig

    2013-08-01

    Full Text Available The Dearfield Dream Project is a collaborative research initiative to conduct historical, cultural, archaeological, and environmental studies on the early 20th Century African-American colony site of Dearfield, Colorado, USA. Because the breadth and significance of the Dearfield Project requires an interdisciplinary research team, a network of research collaborators has been assembled. This research network seeks to discover, preserve, and disseminate knowledge of the site and its surrounding farmsteads’ economic, social, political, and environmental history for better understanding and interpretation of its contributions to Colorado and U.S. history. Herein, we detail progress that has been made on this important historical/cultural research project. Further, we outline the future of the Dearfield research network along with our current and anticipated subjects of inquiry.

  2. A study of epileptogenic network structures in rat hippocampal cultures using first spike latencies during synchronization events

    International Nuclear Information System (INIS)

    Raghavan, Mohan; Amrutur, Bharadwaj; Srinivas, Kalyan V; Sikdar, Sujit K

    2012-01-01

    Study of hypersynchronous activity is of prime importance for combating epilepsy. Studies on network structure typically reconstruct the network by measuring various aspects of the interaction between neurons and subsequently measure the properties of the reconstructed network. In sub-sampled networks such methods lead to significant errors in reconstruction. Using rat hippocampal neurons cultured on a multi-electrode array dish and a glutamate injury model of epilepsy in vitro, we studied synchronous activity in neuronal networks. Using the first spike latencies in various neurons during a network burst, we extract various recurring spatio-temporal onset patterns in the networks. Comparing the patterns seen in control and injured networks, we observe that injured networks express a wide diversity in their foci (origin) and activation pattern, while control networks show limited diversity. Furthermore, we note that onset patterns in glutamate injured networks show a positive correlation between synchronization delay and physical distance between neurons, while control networks do not. (paper)

  3. Voltage-sensitive dye recording from networks of cultured neurons

    Science.gov (United States)

    Chien, Chi-Bin

    This thesis describes the development and testing of a sensitive apparatus for recording electrical activity from microcultures of rat superior cervical ganglion (SCG) neurons by using voltage-sensitive fluorescent dyes.The apparatus comprises a feedback-regulated mercury arc light source, an inverted epifluorescence microscope, a novel fiber-optic camera with discrete photodiode detectors, and low-noise preamplifiers. Using an NA 0.75 objective and illuminating at 10 W/cm2 with the 546 nm mercury line, a typical SCG neuron stained with the styryl dye RH423 gives a detected photocurrent of 1 nA; the light source and optical detectors are quiet enough that the shot noise in this photocurrent--about.03% rms--dominates. The design, theory, and performance of this dye-recording apparatus are discussed in detail.Styryl dyes such as RH423 typically give signals of 1%/100 mV on these cells; the signals are linear in membrane potential, but do not appear to arise from a purely electrochromic mechanism. Given this voltage sensitivity and the noise level of the apparatus, it should be possible to detect both action potentials and subthreshold synaptic potentials from SCG cell bodies. In practice, dye recording can easily detect action potentials from every neuron in an SCG microculture, but small synaptic potentials are obscured by dye signals from the dense network of axons.In another microculture system that does not have such long and complex axons, this dye-recording apparatus should be able to detect synaptic potentials, making it possible to noninvasively map the synaptic connections in a microculture, and thus to study long-term synaptic plasticity.

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

    Science.gov (United States)

    Ingber, Lester

    1995-10-01

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

  5. Experience-Dependent Regulation of Presynaptic NMDARs Enhances Neurotransmitter Release at Neocortical Synapses

    Science.gov (United States)

    Urban-Ciecko, Joanna; Wen, Jing A.; Parekh, Puja K.; Barth, Alison L.

    2015-01-01

    Sensory experience can selectively alter excitatory synaptic strength at neocortical synapses. The rapid increase in synaptic strength induced by selective whisker stimulation (single-row experience/SRE, where all but one row of whiskers has been removed from the mouse face) is due, at least in part, to the trafficking of AMPA receptors (AMPARs)…

  6. Reduced cell number in the neocortical part of the human fetal brain in Down syndrome

    DEFF Research Database (Denmark)

    Larsen, K.B.; Laursen, H.; Graem, N.

    2008-01-01

    Mental retardation is seen in all individuals with Down syndrome (DS) and different brain abnormalities are reported. The aim of this study was to investigate if mental retardation at least in part is a result of a lower cell number in the neocortical part of the human fetal forebrain. We therefore...

  7. Locally Applied Valproate Enhances Survival in Rats after Neocortical Treatment with Tetanus Toxin and Cobalt Chloride

    Directory of Open Access Journals (Sweden)

    Dirk-Matthias Altenmüller

    2013-01-01

    Full Text Available Purpose. In neocortical epilepsies not satisfactorily responsive to systemic antiepileptic drug therapy, local application of antiepileptic agents onto the epileptic focus may enhance treatment efficacy and tolerability. We describe the effects of focally applied valproate (VPA in a newly emerging rat model of neocortical epilepsy induced by tetanus toxin (TeT plus cobalt chloride (CoCl2. Methods. In rats, VPA ( or sodium chloride (NaCl ( containing polycaprolactone (PCL implants were applied onto the right motor cortex treated before with a triple injection of 75 ng TeT plus 15 mg CoCl2. Video-EEG monitoring was performed with intracortical depth electrodes. Results. All rats randomized to the NaCl group died within one week after surgery. In contrast, the rats treated with local VPA survived significantly longer (. In both groups, witnessed deaths occurred in the context of seizures. At least of the rats surviving the first postoperative day developed neocortical epilepsy with recurrent spontaneous seizures. Conclusions. The novel TeT/CoCl2 approach targets at a new model of neocortical epilepsy in rats and allows the investigation of local epilepsy therapy strategies. In this vehicle-controlled study, local application of VPA significantly enhanced survival in rats, possibly by focal antiepileptic or antiepileptogenic mechanisms.

  8. Assessing the permeability of engineered capillary networks in a 3D culture.

    Directory of Open Access Journals (Sweden)

    Stephanie J Grainger

    Full Text Available Many pathologies are characterized by poor blood vessel growth and reduced nutrient delivery to the surrounding tissue, introducing a need for tissue engineered blood vessels. Our lab has developed a 3D co-culture method to grow interconnected networks of pericyte-invested capillaries, which can anastamose with host vasculature following implantation to restore blood flow to ischemic tissues. However, if the engineered vessels contain endothelial cells (ECs that are misaligned or contain wide junctional gaps, they may function improperly and behave more like the pathologic vessels that nourish tumors. The purpose of this study was to test the resistance to permeability of these networks in vitro, grown with different stromal cell types, as a metric of vessel functionality. A fluorescent dextran tracer was used to visualize transport across the endothelium and the pixel intensity was quantified using a customized MATLAB algorithm. In fibroblast-EC co-cultures, the dextran tracer easily penetrated through the vessel wall and permeability was high through the first 5 days of culture, indicative of vessel immaturity. Beyond day 5, dextran accumulated at the periphery of the vessel, with very little transported across the endothelium. Quantitatively, permeability dropped from initial levels of 61% to 39% after 7 days, and to 7% after 2 weeks. When ECs were co-cultured with bone marrow-derived mesenchymal stem cells (MSCs or adipose-derived stem cells (AdSCs, much tighter control of permeability was achieved. Relative to the EC-fibroblast co-cultures, permeabilities were reduced 41% for the EC-MSC co-cultures and 50% for the EC-AdSC co-cultures after 3 days of culture. By day 14, these permeabilities decreased by 68% and 77% over the EC-fibroblast cultures. Co-cultures containing stem cells exhibit elevated VE-cadherin levels and more prominent EC-EC junctional complexes when compared to cultures containing fibroblasts. These data suggest the stromal

  9. Acceptance and Quality Perceptions of Social Network Services in Cultural Context: Vkontakte as a Case Study

    Directory of Open Access Journals (Sweden)

    Katsiaryna S. Baran

    2015-06-01

    Full Text Available In terms of network economics, as well as other information services, a social network service (SNS has two chances–either it gains acceptance ("success breeds success" and will become standard or it slowly dies. Nowadays, Facebook is the standard in the social network world, however, not in Russia's and the neighboring countries' social network communities. Here, Vkontakte, the domestic SNS, dominates. What are the reasons for this success of the regional SNS and the failure of the global giant? We answer this research question while we empirically studied both SNSs, Facebook as well as Vkontakte, among Russian users. In the evaluation, based on the Information Service Evaluation (ISE Model, we found out that Vkontakte is perceived as more useful than Facebook, is much more trustworthy, and more enjoyable to use. The cultural environment of the Russian community plays an important role as well.

  10. Negotiating Intra-Asian Games Networks: On Cultural Proximity, East Asian Games Design, and Chinese Farmers

    Directory of Open Access Journals (Sweden)

    Dean Chan

    2006-01-01

    Full Text Available A key feature of networked games in East Asia is the relationship between the adaptation of regional Asian aesthetic and narrative forms in game content, and the parallel growth in more regionally-focused marketing and distribution initiatives. This essay offers a contextual analysis of intra-Asian games networks, with reference to the production, marketing and circulation of Asian MMORPGs. My discussion locates these networks as part of broader discourses on regionalism, East Asian cultural production and Asian modernity. At the same time, I consider how these networks highlight structural asymmetry and uneven power relations within the region; and I examine the emergent use of gamer-workers known as Chinese farmers in the digital game-items trade.

  11. Undergraduate students' development of social, cultural, and human capital in a networked research experience

    Science.gov (United States)

    Thompson, Jennifer Jo; Conaway, Evan; Dolan, Erin L.

    2016-12-01

    Recent calls for reform in undergraduate biology education have emphasized integrating research experiences into the learning experiences of all undergraduates. Contemporary science research increasingly demands collaboration across disciplines and institutions to investigate complex research questions, providing new contexts and models for involving undergraduates in research. In this study, we examined the experiences of undergraduates participating in a multi-institution and interdisciplinary biology research network. Unlike the traditional apprenticeship model of research, in which a student participates in research under the guidance of a single faculty member, students participating in networked research have the opportunity to develop relationships with additional faculty and students working in other areas of the project, at their own and at other institutions. We examined how students in this network develop social ties and to what extent a networked research experience affords opportunities for students to develop social, cultural, and human capital. Most studies of undergraduate involvement in science research have focused on documenting student outcomes rather than elucidating how students gain access to research experiences or how elements of research participation lead to desired student outcomes. By taking a qualitative approach framed by capital theories, we have identified ways that undergraduates utilize and further develop various forms of capital important for success in science research. In our study of the first 16 months of a biology research network, we found that undergraduates drew upon a combination of human, cultural, and social capital to gain access to the network. Within their immediate research groups, students built multidimensional social ties with faculty, peers, and others, yielding social capital that can be drawn upon for information, resources, and support. They reported developing cultural capital in the form of learning to

  12. New Challenges for Urban History: Culture, Networks, Globalization

    Directory of Open Access Journals (Sweden)

    Hietala, Marjatta

    2012-12-01

    Full Text Available Urban history is a very lively and dynamic research field, showing strict parallelism with the fast increasing of the urban population. Today, competitiveness is one of the key aims for cities in the globalized world. Factors such as accessibility and infrastructure, industry, human capital, innovation, and investment, green spaces, affordable housing, business support and quality of education are necessaries. However, the OECD recognizes three dilemmas in this strategic vision, concerning the spill over of metro-regions, the public strategic vision, and the relationship between economic dynamism and the liveable city. Today urban historians are facing some general challenges: comparative aspects are needed; also interdisciplinarity to develop cooperation between disciplines; and for maintaining the professional status of academic urban history. The expanding networks between towns and cities, and the meeting places as conferences and exhibitions are considered, as they are the multitudinous challenges and threats, especially for those cities suffering continuously of major natural and man-made disasters. Moreover, new amalgams of hazard are being created in metropolitan areas with overlapping natural, technological, biological and social risks, exposing more people and places, needing safety and security.

    La historia urbana es un campo de investigación muy vivo y dinámico, mostrando un paralelismo estricto con el rápido incremento de la población urbana. La competencia es hoy uno de los objetivos claves para las ciudades en el mundo globalizado. Factores tales como la accesibilidad y las infraestructuras, la industria, el capital humano, la innovación y la inversión, los espacios verdes, la vivienda accesible, el apoyo a los negocios y la calidad de la educación son necesarios. Sin embargo, la OCDE reconoce tres dilemas en esa visión estratégica, el desarrollo de las metrópolis, la visión estratégica pública y la relaci

  13. Statistical mechanics of neocortical interactions: A scaling paradigm applied to electroencephalography

    Science.gov (United States)

    Ingber, Lester

    1991-09-01

    A series of papers has developed a statistical mechanics of neocortical interactions (SMNI), deriving aggregate behavior of experimentally observed columns of neurons from statistical electrical-chemical properties of synaptic interactions. While not useful to yield insights at the single-neuron level, SMNI has demonstrated its capability in describing large-scale properties of short-term memory and electroencephalographic (EEG) systematics. The necessity of including nonlinear and stochastic structures in this development has been stressed. In this paper, a more stringent test is placed on SMNI: The algebraic and numerical algorithms previously developed in this and similar systems are brought to bear to fit large sets of EEG and evoked-potential data being collected to investigate genetic predispositions to alcoholism and to extract brain ``signatures'' of short-term memory. Using the numerical algorithm of very fast simulated reannealing, it is demonstrated that SMNI can indeed fit these data within experimentally observed ranges of its underlying neuronal-synaptic parameters, and the quantitative modeling results are used to examine physical neocortical mechanisms to discriminate high-risk and low-risk populations genetically predisposed to alcoholism. Since this study is a control to span relatively long time epochs, similar to earlier attempts to establish such correlations, this discrimination is inconclusive because of other neuronal activity which can mask such effects. However, the SMNI model is shown to be consistent with EEG data during selective attention tasks and with neocortical mechanisms describing short-term memory previously published using this approach. This paper explicitly identifies similar nonlinear stochastic mechanisms of interaction at the microscopic-neuronal, mesoscopic-columnar, and macroscopic-regional scales of neocortical interactions. These results give strong quantitative support for an accurate intuitive picture, portraying

  14. Word-of-Mouth of Cultural Products through Institutional Social Networks

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    Eun Ea Lee

    2017-05-01

    Full Text Available Recently, a number of cultural institutions such as museums, galleries, art auctions, events, and performance centers have been utilizing social network sites (SNS for promoting and marketing their culture, art content, and events. The online social space is appropriate for cultural products to be viral, since users of SNS mainly share personal interest and spread hedonic consumption with close friends and acquaintances. If viral content drives strong emotions such as joy, arousal, pleasure, sorrow, or horror, it will be transmitted to more people, and rapidly. This study investigates how a certain type of motivation for using a social network service such as Facebook influences trust in art and culture exhibition information providers and the content of the information itself. Results show that people who have an informational motivation for using social media expressed a higher degree of trust in exhibition information provided by institutions such as museums. On the contrary, those who have relational motivation for using social media credited acquaintances such as friends, families, and colleagues more. Trust in the information provider resulted in trust in the content itself, and hence, increased the possibility of word-of-mouth for the corresponding information. An empirical survey was implemented, using followers of the Facebook page of a national museum and users who clicked “Like” on postings of exhibitions. Finally, the potential applications of the result for promotion and marketing of exhibitions of art and culture for public will be discussed.

  15. Minimal Camera Networks for 3D Image Based Modeling of Cultural Heritage Objects

    Science.gov (United States)

    Alsadik, Bashar; Gerke, Markus; Vosselman, George; Daham, Afrah; Jasim, Luma

    2014-01-01

    3D modeling of cultural heritage objects like artifacts, statues and buildings is nowadays an important tool for virtual museums, preservation and restoration. In this paper, we introduce a method to automatically design a minimal imaging network for the 3D modeling of cultural heritage objects. This becomes important for reducing the image capture time and processing when documenting large and complex sites. Moreover, such a minimal camera network design is desirable for imaging non-digitally documented artifacts in museums and other archeological sites to avoid disturbing the visitors for a long time and/or moving delicate precious objects to complete the documentation task. The developed method is tested on the Iraqi famous statue “Lamassu”. Lamassu is a human-headed winged bull of over 4.25 m in height from the era of Ashurnasirpal II (883–859 BC). Close-range photogrammetry is used for the 3D modeling task where a dense ordered imaging network of 45 high resolution images were captured around Lamassu with an object sample distance of 1 mm. These images constitute a dense network and the aim of our study was to apply our method to reduce the number of images for the 3D modeling and at the same time preserve pre-defined point accuracy. Temporary control points were fixed evenly on the body of Lamassu and measured by using a total station for the external validation and scaling purpose. Two network filtering methods are implemented and three different software packages are used to investigate the efficiency of the image orientation and modeling of the statue in the filtered (reduced) image networks. Internal and external validation results prove that minimal image networks can provide highly accurate records and efficiency in terms of visualization, completeness, processing time (>60% reduction) and the final accuracy of 1 mm. PMID:24670718

  16. Minimal camera networks for 3D image based modeling of cultural heritage objects.

    Science.gov (United States)

    Alsadik, Bashar; Gerke, Markus; Vosselman, George; Daham, Afrah; Jasim, Luma

    2014-03-25

    3D modeling of cultural heritage objects like artifacts, statues and buildings is nowadays an important tool for virtual museums, preservation and restoration. In this paper, we introduce a method to automatically design a minimal imaging network for the 3D modeling of cultural heritage objects. This becomes important for reducing the image capture time and processing when documenting large and complex sites. Moreover, such a minimal camera network design is desirable for imaging non-digitally documented artifacts in museums and other archeological sites to avoid disturbing the visitors for a long time and/or moving delicate precious objects to complete the documentation task. The developed method is tested on the Iraqi famous statue "Lamassu". Lamassu is a human-headed winged bull of over 4.25 m in height from the era of Ashurnasirpal II (883-859 BC). Close-range photogrammetry is used for the 3D modeling task where a dense ordered imaging network of 45 high resolution images were captured around Lamassu with an object sample distance of 1 mm. These images constitute a dense network and the aim of our study was to apply our method to reduce the number of images for the 3D modeling and at the same time preserve pre-defined point accuracy. Temporary control points were fixed evenly on the body of Lamassu and measured by using a total station for the external validation and scaling purpose. Two network filtering methods are implemented and three different software packages are used to investigate the efficiency of the image orientation and modeling of the statue in the filtered (reduced) image networks. Internal and external validation results prove that minimal image networks can provide highly accurate records and efficiency in terms of visualization, completeness, processing time (>60% reduction) and the final accuracy of 1 mm.

  17. Barriers of Culture, Networks, and Language in International Migration: A Review

    Directory of Open Access Journals (Sweden)

    Zhiling Wang

    2018-05-01

    Full Text Available Along with the increasing pace of globalization, recent decades faced a dramatically increase in international migrant flows as well. Compared to the flows of trade, capital and knowledge, we observe that contemporaneous complex institutional differences, historical backgrounds, and individuals' diverse socio-demographic characteristics make the migrant workers' choice of destination arguably much more uncontrollable. This study shows that migration is in a complex way intertwined with culture, networks and language, (i by reviewing related studies on the barriers of culture, networks and language in international labor mobility, and (ii by exploring missing gaps and prospective avenues for research. Nowadays, the migration pressure on Europe and the United states has created substantial challenges, leading to an urgent need to address the economic assimilation and social integration of migrants. Against this background, we emphasize that these non-economic factors have played an increasingly critical role in shaping international migration and its future socio-economic consequences for destination countries.

  18. The role of learning analytics in networking for business and leisure: A study of culture and gender differences in social platform users

    OpenAIRE

    Benson, Vladlena; Filippaios, Fragkiskos

    2018-01-01

    Engagement with social networking sites is influenced by the cognitive and learning processes which in turn is influenced by culture. This paper aims at unbundling the effect of culture on the use of social network sites and thus contributes to our understanding on the way cognitive and learning processes influence the engagement with social networks. The study of over 600 social networking users addresses how professional and leisure use of social networks differs across cultures, gender and...

  19. Cultural Routes and Networks of Knowledge: the Identity and Promotion of Cultural Heritage. The Case Study of Piedmont

    Directory of Open Access Journals (Sweden)

    Silvia Beltramo

    2013-07-01

    Full Text Available The European project called “PER VIAM Pilgrims’ Routes In Action”, funded by the European Commission in 2012, is a significant opportunity of cultural and economic development for the whole Europe and also for the territory of Piedmont Region. The certainty of the need for transnational cooperation, which should create a network amongst the different territories in a perspective of working together and exchange of traveling, economic and cultural experiences – as well as best practices - nowadays calls for implementation tools such as European projects supported and sought for by the local authorities.The Piedmont is nowadays crossed by various cultural itineraries, many of which are certificated by the European Council: Via Francigena, the Route of the Cistercian Abbeys, the Transromanica, the itinerary of the historical thermal cities and the Saint Michael's way. Starting from a survey on the meaning of "cultural itinerary" expressed by the different European institutions (i.e. ICOMOS, UNESCO, Council of Europe and European Commission, this essay is proposing an analysis of the current status of such territory, highlighting the public policies in progress, the role and activities of the local associations and the valorisation of implemented projects as related to those itineraries which have already been recognized by the Council of Europe.This paper presents some significant experiences and best practices in the study of religious tourism, as they have been defined on the regional territory throughout the last few years, which can contribute to the debate and to the overall awareness on management and valorization of sustainable tourism. 

  20. A moveable feast: Contemporary relational food cultures emerging from local food networks.

    Science.gov (United States)

    O'Kane, Gabrielle

    2016-10-01

    Although the globalised food system delivers unparalleled food variety and quantity to most in the developed world it also disconnects consumers from where, how and by whom food is grown. This change in the food system has resulted in an acceptance of an anonymous and homogeneous food supply, which has contributed to over-consumption and the rise in diet-related diseases. 'Nutritionism' responds to this issue by maintaining that a 'healthy diet' can be achieved by consuming the correct balance of energy and nutrients, but with limited success. Yet, some food cultures can moderate the effects of the environmental drivers of increasing global obesity rates. This paper draws on this premise and presents an alternative eco-dietetic response, exploring people's meaning-making of food and food culture through local food networks. This research used narrative inquiry methodology and purposive sampling to gather stories through focus group conversations. Twenty people attended focus groups comprised of food procurers from one of three local food networks in the Canberra region: community gardens, a modified Community Supported Agriculture (CSA) and farmers' markets. The findings showed that those using local food networks enjoyed a 'contemporary relational food culture' that highlighted the importance of people, place and time, in their visceral experiences of food. The community gardeners made meaning of food through their connections to the earth and to others. The farmers' market and CSA food procurers valued the seasonal, local and ethical food produced by their beloved farmer(s). This paper provides qualitative evidence that local food networks enable people to enjoy multi-dimensional relationships to food. Further research is required to examine whether experiencing a contemporary relational food culture can lead to improved health outcomes for people and the planet. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Adaptive enhancement of learning protocol in hippocampal cultured networks grown on multielectrode arrays

    Science.gov (United States)

    Pimashkin, Alexey; Gladkov, Arseniy; Mukhina, Irina; Kazantsev, Victor

    2013-01-01

    Learning in neuronal networks can be investigated using dissociated cultures on multielectrode arrays supplied with appropriate closed-loop stimulation. It was shown in previous studies that weakly respondent neurons on the electrodes can be trained to increase their evoked spiking rate within a predefined time window after the stimulus. Such neurons can be associated with weak synaptic connections in nearby culture network. The stimulation leads to the increase in the connectivity and in the response. However, it was not possible to perform the learning protocol for the neurons on electrodes with relatively strong synaptic inputs and responding at higher rates. We proposed an adaptive closed-loop stimulation protocol capable to achieve learning even for the highly respondent electrodes. It means that the culture network can reorganize appropriately its synaptic connectivity to generate a desired response. We introduced an adaptive reinforcement condition accounting for the response variability in control stimulation. It significantly enhanced the learning protocol to a large number of responding electrodes independently on its base response level. We also found that learning effect preserved after 4–6 h after training. PMID:23745105

  2. Graph-based unsupervised segmentation algorithm for cultured neuronal networks' structure characterization and modeling.

    Science.gov (United States)

    de Santos-Sierra, Daniel; Sendiña-Nadal, Irene; Leyva, Inmaculada; Almendral, Juan A; Ayali, Amir; Anava, Sarit; Sánchez-Ávila, Carmen; Boccaletti, Stefano

    2015-06-01

    Large scale phase-contrast images taken at high resolution through the life of a cultured neuronal network are analyzed by a graph-based unsupervised segmentation algorithm with a very low computational cost, scaling linearly with the image size. The processing automatically retrieves the whole network structure, an object whose mathematical representation is a matrix in which nodes are identified neurons or neurons' clusters, and links are the reconstructed connections between them. The algorithm is also able to extract any other relevant morphological information characterizing neurons and neurites. More importantly, and at variance with other segmentation methods that require fluorescence imaging from immunocytochemistry techniques, our non invasive measures entitle us to perform a longitudinal analysis during the maturation of a single culture. Such an analysis furnishes the way of individuating the main physical processes underlying the self-organization of the neurons' ensemble into a complex network, and drives the formulation of a phenomenological model yet able to describe qualitatively the overall scenario observed during the culture growth. © 2014 International Society for Advancement of Cytometry.

  3. Differential antiepileptic effects of the organic calcium antagonists verapamil and flunarizine in neurons of organotypic neocortical explants from newborn rats

    NARCIS (Netherlands)

    Bingmann, D; Speckmann, E J; Baker, R E; Ruijter, J; de Jong, B. M.

    1988-01-01

    Effects of the organic calcium antagonists verapamil and flunarizine on pentylenetetrazol induced paroxysmal depolarizations were tested in organotypic neocortical explants taken from neonatal rats. In these in vitro experiments the papaverin derivative verapamil depressed, and finally abolished,

  4. Accuracy of typical photogrammetric networks in cultural heritage 3D modeling projects

    Directory of Open Access Journals (Sweden)

    E. Nocerino

    2014-06-01

    Full Text Available The easy generation of 3D geometries (point clouds or polygonal models with fully automated image-based methods poses nontrivial problems on how to check a posteriori the quality of the achieved results. Clear statements and procedures on how to plan the camera network, execute the survey and use automatic tools to achieve the prefixed requirements are still an open issue. Although such issues had been discussed and solved some years ago, the importance of camera network geometry is today often underestimated or neglected in the cultural heritage field. In this paper different camera network geometries, with normal and convergent images, are analyzed and the accuracy of the produced results are compared to ground truth measurements.

  5. The neural correlates of persuasion: a common network across cultures and media.

    Science.gov (United States)

    Falk, Emily B; Rameson, Lian; Berkman, Elliot T; Liao, Betty; Kang, Yoona; Inagaki, Tristen K; Lieberman, Matthew D

    2010-11-01

    Persuasion is at the root of countless social exchanges in which one person or group is motivated to have another share its beliefs, desires, or behavioral intentions. Here, we report the first three functional magnetic resonance imaging studies to investigate the neurocognitive networks associated with feeling persuaded by an argument. In the first two studies, American and Korean participants, respectively, were exposed to a number of text-based persuasive messages. In both Study 1 and Study 2, feeling persuaded was associated with increased activity in posterior superior temporal sulcus bilaterally, temporal pole bilaterally, and dorsomedial prefrontal cortex. The findings suggest a discrete set of underlying mechanisms in the moment that the persuasion process occurs, and are strengthened by the fact that the results replicated across two diverse linguistic and cultural groups. Additionally, a third study using region-of-interest analyses demonstrated that neural activity in this network was also associated with persuasion when a sample of American participants viewed video-based messages. In sum, across three studies, including two different cultural groups and two types of media, persuasion was associated with a consistent network of regions in the brain. Activity in this network has been associated with social cognition and mentalizing and is consistent with models of persuasion that emphasize the importance of social cognitive processing in determining the efficacy of persuasive communication.

  6. Developing a culturally competent health network: a planning framework and guide.

    Science.gov (United States)

    Gertner, Eric J; Sabino, Judith N; Mahady, Erica; Deitrich, Lynn M; Patton, Jarret R; Grim, Mary Kay; Geiger, James F; Salas-Lopez, Debbie

    2010-01-01

    The number of cultural competency initiatives in healthcare is increasing due to many factors, including changing demographics, quality improvement and regulatory requirements, equitable care missions, and accreditation standards. To facilitate organization-wide transformation, a hospital or healthcare system must establish strategic goals, objectives, and implementation tasks for culturally competent provision of care. This article reports the largely successful results of a cultural competency program instituted at a large system in eastern Pennsylvania. Prior to the development of its cultural competency initiative, Lehigh Valley Health Network, Allentown, Pennsylvania, saw isolated activities producing innovative solutions to diversity and culture issues in the provision of equitable care. But it took a transformational event to support an organization-wide program in cultural competency by strengthening leadership buy-in and providing a sense of urgency, excitement, and shared vision among multiple stakeholders. A multidisciplinary task force, including senior leaders and a diverse group of employees, was created with the authority and responsibility to enact changes. Through a well-organized strategic planning process, existing patient and community demographic data were reviewed to describe existing disparities, a baseline assessment was completed, a mission statement was created, and clear metrics were developed. The strategic plan, which focused on five key areas (demographics, language-appropriate services, employees, training, and education/communication), was approved by the network's chief executive officer and senior managers to demonstrate commitment prior to implementation. Strategic plan implementation proceeded through a project structure consisting of subproject teams charged with achieving the following specific objectives: develop a cultural material repository, enhance employee recruitment/retention, establish a baseline assessment

  7. Relations, interactions and networks of cultural tourism stakeholders in rural areas of Vojvodina

    Directory of Open Access Journals (Sweden)

    Pavlović Nataša

    2015-01-01

    Full Text Available Contemporary trends, which are characterized by a very strong level of competition and the maturity of the market, become more than ever essential for success of tourist destinations. Rural areas in Vojvodina, because of its authentic atmosphere and multiculturalism, have significant advantages for cultural tourism. Each participant who creates a tourism product in toda y's competitive environment aims to have a strong focus on customer satisfaction, which indicates the necessity of adopting the concept of total relationship marketing. The aim of this paper is to show how cultural institutions, souvenir craftsmen, tourism organizations, travel agencies and other stakeholders achieve cooperation and apply modern concept of total relationship marketing for the purposes of satisfying the needs of tourists. The paper will explore the fundamental postulates of relationship marketing applied by key stakeholders of cultural tourism in rural areas, and will get reference results on relations, interactions and networks.

  8. Surgical Treatment of Nonlesional Neocortical Epilepsy: Long-term Longitudinal Study.

    Science.gov (United States)

    Kim, Dong Wook; Lee, Sang Kun; Moon, Hye-Jin; Jung, Ki-Young; Chu, Kon; Chung, Chun-Ki

    2017-03-01

    The proportion of surgery for nonlesional neocortical epilepsy has recently increased, with a decrease in surgery for mesial temporal lobe epilepsy. However, there are only a few studies regarding the long-term surgical outcome and the potential prognostic factors for patients with nonlesional neocortical epilepsy. To evaluate the long-term surgical outcome and to identify possible prognostic factors in patients with nonlesional neocortical epilepsy. In a surgical cohort from September 1995 to December 2005 at the Seoul National University Hospital, we included 109 consecutive patients without lesions identifiable by magnetic resonance imaging who underwent focal surgical resection for drug-resistant neocortical epilepsy. Follow-up information for at least 10 years was available for all but 1 patient. Univariate and standard multiple logistic regression analyses were performed to identify the predictors of surgical outcomes, and a generalized estimation equation model was used for the longitudinal multiple logistic regression analysis of up to 21 years of follow-up. The patients consisted of 64 men and 45 women with ages at surgery ranging from 7 to 56 years (mean [SD], 27.1 [7.8] years). At 1 year after surgery, 59 of 109 patients (54.1%) achieved seizure freedom, and 64 of 108 patients (59.3%) achieved seizure freedom at the last follow-up. Only 11 of 108 patients (10.2%) experienced definite changes in postoperative seizure status. Localizing patterns in functional neuroimaging (strongest odds ratio [OR], 0.30 [95% CI, 0.14-0.66] for fluorodeoxyglucose-positron emission tomography; 0.37 [95% CI, 0.15-0.87] for ictal single-photon emission computed tomography), concordant results in presurgical diagnostic evaluations (OR, 3.15 [95% CI, 1.42-7.02]), the presence of aura (OR, 3.49 [95% CI, 1.54-7.92]), and complete resection of areas of ictal onset with frequent interictal spikes during the intracranial electroencephalographic study (OR, 0.37 [95% CI, 0

  9. Characterizing steady states of genome-scale metabolic networks in continuous cell cultures.

    Directory of Open Access Journals (Sweden)

    Jorge Fernandez-de-Cossio-Diaz

    2017-11-01

    Full Text Available In the continuous mode of cell culture, a constant flow carrying fresh media replaces culture fluid, cells, nutrients and secreted metabolites. Here we present a model for continuous cell culture coupling intra-cellular metabolism to extracellular variables describing the state of the bioreactor, taking into account the growth capacity of the cell and the impact of toxic byproduct accumulation. We provide a method to determine the steady states of this system that is tractable for metabolic networks of arbitrary complexity. We demonstrate our approach in a toy model first, and then in a genome-scale metabolic network of the Chinese hamster ovary cell line, obtaining results that are in qualitative agreement with experimental observations. We derive a number of consequences from the model that are independent of parameter values. The ratio between cell density and dilution rate is an ideal control parameter to fix a steady state with desired metabolic properties. This conclusion is robust even in the presence of multi-stability, which is explained in our model by a negative feedback loop due to toxic byproduct accumulation. A complex landscape of steady states emerges from our simulations, including multiple metabolic switches, which also explain why cell-line and media benchmarks carried out in batch culture cannot be extrapolated to perfusion. On the other hand, we predict invariance laws between continuous cell cultures with different parameters. A practical consequence is that the chemostat is an ideal experimental model for large-scale high-density perfusion cultures, where the complex landscape of metabolic transitions is faithfully reproduced.

  10. The Genetic Association Between Neocortical Volume and General Cognitive Ability Is Driven by Global Surface Area Rather Than Thickness.

    Science.gov (United States)

    Vuoksimaa, Eero; Panizzon, Matthew S; Chen, Chi-Hua; Fiecas, Mark; Eyler, Lisa T; Fennema-Notestine, Christine; Hagler, Donald J; Fischl, Bruce; Franz, Carol E; Jak, Amy; Lyons, Michael J; Neale, Michael C; Rinker, Daniel A; Thompson, Wesley K; Tsuang, Ming T; Dale, Anders M; Kremen, William S

    2015-08-01

    Total gray matter volume is associated with general cognitive ability (GCA), an association mediated by genetic factors. It is expectable that total neocortical volume should be similarly associated with GCA. Neocortical volume is the product of thickness and surface area, but global thickness and surface area are unrelated phenotypically and genetically in humans. The nature of the genetic association between GCA and either of these 2 cortical dimensions has not been examined. Humans possess greater cognitive capacity than other species, and surface area increases appear to be the primary driver of the increased size of the human cortex. Thus, we expected neocortical surface area to be more strongly associated with cognition than thickness. Using multivariate genetic analysis in 515 middle-aged twins, we demonstrated that both the phenotypic and genetic associations between neocortical volume and GCA are driven primarily by surface area rather than thickness. Results were generally similar for each of 4 specific cognitive abilities that comprised the GCA measure. Our results suggest that emphasis on neocortical surface area, rather than thickness, could be more fruitful for elucidating neocortical-GCA associations and identifying specific genes underlying those associations. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Investigation of global and local network properties of music perception with culturally different styles of music.

    Science.gov (United States)

    Li, Yan; Rui, Xue; Li, Shuyu; Pu, Fang

    2014-11-01

    Graph theoretical analysis has recently become a popular research tool in neuroscience, however, there have been very few studies on brain responses to music perception, especially when culturally different styles of music are involved. Electroencephalograms were recorded from ten subjects listening to Chinese traditional music, light music and western classical music. For event-related potentials, phase coherence was calculated in the alpha band and then constructed into correlation matrices. Clustering coefficients and characteristic path lengths were evaluated for global properties, while clustering coefficients and efficiency were assessed for local network properties. Perception of light music and western classical music manifested small-world network properties, especially with a relatively low proportion of weights of correlation matrices. For local analysis, efficiency was more discernible than clustering coefficient. Nevertheless, there was no significant discrimination between Chinese traditional and western classical music perception. Perception of different styles of music introduces different network properties, both globally and locally. Research into both global and local network properties has been carried out in other areas; however, this is a preliminary investigation aimed at suggesting a possible new approach to brain network properties in music perception. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    OpenAIRE

    Ingber, Lester

    1984-01-01

    A theory developed by the author to describe macroscopic neocortical interactions demonstrates that empirical values of chemical and electrical parameters of synaptic interactions establish several minima of the path-integral Lagrangian as a function of excitatory and inhibitory columnar firings. The number of possible minima, their time scales of hysteresis and probable reverberations, and their nearest-neighbor columnar interactions are all consistent with well-established empirical rules o...

  13. Functional Stem Cell Integration into Neural Networks Assessed by Organotypic Slice Cultures.

    Science.gov (United States)

    Forsberg, David; Thonabulsombat, Charoensri; Jäderstad, Johan; Jäderstad, Linda Maria; Olivius, Petri; Herlenius, Eric

    2017-08-14

    Re-formation or preservation of functional, electrically active neural networks has been proffered as one of the goals of stem cell-mediated neural therapeutics. A primary issue for a cell therapy approach is the formation of functional contacts between the implanted cells and the host tissue. Therefore, it is of fundamental interest to establish protocols that allow us to delineate a detailed time course of grafted stem cell survival, migration, differentiation, integration, and functional interaction with the host. One option for in vitro studies is to examine the integration of exogenous stem cells into an existing active neural network in ex vivo organotypic cultures. Organotypic cultures leave the structural integrity essentially intact while still allowing the microenvironment to be carefully controlled. This allows detailed studies over time of cellular responses and cell-cell interactions, which are not readily performed in vivo. This unit describes procedures for using organotypic slice cultures as ex vivo model systems for studying neural stem cell and embryonic stem cell engraftment and communication with CNS host tissue. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  14. Culture-related differences in default network activity during visuo-spatial judgments.

    Science.gov (United States)

    Goh, Joshua O S; Hebrank, Andrew C; Sutton, Bradley P; Chee, Michael W L; Sim, Sam K Y; Park, Denise C

    2013-02-01

    Studies on culture-related differences in cognition have shown that Westerners attend more to object-related information, whereas East Asians attend more to contextual information. Neural correlates of these different culture-related visual processing styles have been reported in the ventral-visual and fronto-parietal regions. We conducted an fMRI study of East Asians and Westerners on a visuospatial judgment task that involved relative, contextual judgments, which are typically more challenging for Westerners. Participants judged the relative distances between a dot and a line in visual stimuli during task blocks and alternated finger presses during control blocks. Behaviorally, East Asians responded faster than Westerners, reflecting greater ease of the task for East Asians. In response to the greater task difficulty, Westerners showed greater neural engagement compared to East Asians in frontal, parietal, and occipital areas. Moreover, Westerners also showed greater suppression of the default network-a brain network that is suppressed under condition of high cognitive challenge. This study demonstrates for the first time that cultural differences in visual attention during a cognitive task are manifested both by differences in activation in fronto-parietal regions as well as suppression in default regions.

  15. The Performance of Ictal Brain SPECT Localizing for Epileptogenic Zone in Neocortical Epilepsy

    International Nuclear Information System (INIS)

    Kim, Eun Sik; Lee, Dong Soo; Hyun, In Young; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Lee, Sang Kun; Chang, Kee Hyun

    1995-01-01

    The epileptogenic zones should be localized precisely before surgical resection of these zones in intractable epilepsy. The localization is more difficult in patients with neocortical epilepsy than in patients with temporal lobe epilepsy. This study aimed at evaluation of the usefulness of ictal brain perfusion SPECT for the localization of epileptogenic zones in neocortical epilepsy. We compared the performance of ictal SPECT with MRI referring to ictal scalp electroencephalography (sEEG). Ictal 99m Tc-HMPAO SPECT were done in twenty-one patients. Ictal EEG were also obtained during video monitoring. MRI were reviewed. According to the ictal sEEG and semiology, 8 patients were frontal lobe epilepsy, 7 patients were lateral temporal lobe epilepsy, 2 patients were parietal lobe epilepsy, and 4 patients were occipital lobe epilepsy. Ictal SPECT showed hyperperfusion in 14 patients(67%) in the zones which were suspected to be epileptogenic according to ictal EEG and semiology. MRI found morphologic abnormalities in 9 patients(43%). Among the 12 patients, in whom no epileptogenic zones were revealed by MR1, ictal SPECT found zones of hyperperfusion concordant with ictal sEEG in 9 patients(75%). However, no zones of hyperperfusion were found in 4 among 9 patients who were found to have cerebromalacia, abnormal calcification and migration anomaly in MRI. We thought that ictal SPECT was useful for localization of epileptogenic zones in neocortical epilepsy and especially in patients with negative findings in MRI.

  16. Enhancement of Neocortical-Medial Temporal EEG Correlations during Non-REM Sleep

    Directory of Open Access Journals (Sweden)

    Nikolai Axmacher

    2008-01-01

    Full Text Available Interregional interactions of oscillatory activity are crucial for the integrated processing of multiple brain regions. However, while the EEG in virtually all brain structures passes through substantial modifications during sleep, it is still an open question whether interactions between neocortical and medial temporal EEG oscillations also depend on the state of alertness. Several previous studies in animals and humans suggest that hippocampal-neocortical interactions crucially depend on the state of alertness (i.e., waking state or sleep. Here, we analyzed scalp and intracranial EEG recordings during sleep and waking state in epilepsy patients undergoing presurgical evaluation. We found that the amplitudes of oscillations within the medial temporal lobe and the neocortex were more closely correlated during sleep, in particular during non-REM sleep, than during waking state. Possibly, the encoding of novel sensory inputs, which mainly occurs during waking state, requires that medial temporal dynamics are rather independent from neocortical dynamics, while the consolidation of memories during sleep may demand closer interactions between MTL and neocortex.

  17. Divergence and inheritance of neocortical heterotopia in inbred and genetically-engineered mice.

    Science.gov (United States)

    Toia, Alyssa R; Cuoco, Joshua A; Esposito, Anthony W; Ahsan, Jawad; Joshi, Alok; Herron, Bruce J; Torres, German; Bolivar, Valerie J; Ramos, Raddy L

    2017-01-18

    Cortical function emerges from the intrinsic properties of neocortical neurons and their synaptic connections within and across lamina. Neurodevelopmental disorders affecting migration and lamination of the neocortex result in cognitive delay/disability and epilepsy. Molecular layer heterotopia (MLH), a dysplasia characterized by over-migration of neurons into layer I, are associated with cognitive deficits and neuronal hyperexcitability in humans and mice. The breadth of different inbred mouse strains that exhibit MLH and inheritance patterns of heterotopia remain unknown. A neuroanatomical survey of numerous different inbred mouse strains, 2 first filial generation (F1) hybrids, and one consomic strain (C57BL/6J-Chr 1 A/J /NaJ) revealed MLH only in C57BL/6 mice and the consomic strain. Heterotopia were observed in numerous genetically-engineered mouse lines on a congenic C57BL/6 background. These data indicate that heterotopia formation is a weakly penetrant trait requiring homozygosity of one or more C57BL/6 alleles outside of chromosome 1. These data are relevant toward understanding neocortical development and disorders affecting neocortical lamination. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Humans and great apes share increased neocortical neuropeptide Y innervation compared to other haplorhine primates

    Directory of Open Access Journals (Sweden)

    Mary Ann eRaghanti

    2014-02-01

    Full Text Available Neuropeptide Y (NPY plays a role in a variety of basic physiological functions and has also been implicated in regulating cognition, including learning and memory. A decrease in neocortical NPY has been reported for Alzheimer’s disease, schizophrenia, bipolar disorder, and depression, potentially contributing to associated cognitive deficits. The goal of the present analysis was to examine variation in neocortical NPY-immunoreactive axon and varicosity density among haplorhine primates (monkeys, apes, and humans. Stereologic methods were used to measure the ratios of NPY-expressing axon length density to total neuron density (ALv/Nv and NPY-immunoreactive varicosity density to neuron density (Vv/Nv, as well as the mean varicosity spacing in neocortical areas 10, 24, 44, and 22 (Tpt of humans, African great apes, New World monkeys, and Old World monkeys. Humans and great apes showed increased cortical NPY innervation relative to monkey species for ALv/Nv and Vv/Nv. Furthermore, humans and great apes displayed a conserved pattern of varicosity spacing across cortical areas and layers, with no differences between cortical layers or among cortical areas. These phylogenetic differences may be related to shared life history variables and may reflect specific cognitive abilities.

  19. Transcriptional and Post-Transcriptional Mechanisms of the Development of Neocortical Lamination

    Directory of Open Access Journals (Sweden)

    Tatiana Popovitchenko

    2017-11-01

    Full Text Available The neocortex is a laminated brain structure that is the seat of higher cognitive capacity and responses, long-term memory, sensory and emotional functions, and voluntary motor behavior. Proper lamination requires that progenitor cells give rise to a neuron, that the immature neuron can migrate away from its mother cell and past other cells, and finally that the immature neuron can take its place and adopt a mature identity characterized by connectivity and gene expression; thus lamination proceeds through three steps: genesis, migration, and maturation. Each neocortical layer contains pyramidal neurons that share specific morphological and molecular characteristics that stem from their prenatal birth date. Transcription factors are dynamic proteins because of the cohort of downstream factors that they regulate. RNA-binding proteins are no less dynamic, and play important roles in every step of mRNA processing. Indeed, recent screens have uncovered post-transcriptional mechanisms as being integral regulatory mechanisms to neocortical development. Here, we summarize major aspects of neocortical laminar development, emphasizing transcriptional and post-transcriptional mechanisms, with the aim of spurring increased understanding and study of its intricacies.

  20. Democratization or else vulgarization of cultural capital? The role of social networks in theater’s audience behavior

    OpenAIRE

    Carmela Milano

    2015-01-01

    This paper investigates the participation in social networks of theater's audiences. Our purpose is to observe, describe and understand the role of social networks in the consumption behavior of the theater field. In particular, we put the accent on the concept of cultural capital with its social dimension. We realize an exploratory study that consists in a dozen of qualitative semi-structured interviews with theater’s audiences that participate in social networks. We provide an analytical fr...

  1. Networking: a study in planning and developing cross-cultural collaboration

    Directory of Open Access Journals (Sweden)

    Sanjeev Singh

    2002-12-01

    Full Text Available This paper reports on a collaboration between the authors at the University of Brighton (UK and the University of Delhi, South Campus. The collaboration came about as a result of the EU-India Cross-Cultural Innovation Network collaboration programme, a project involving several universities and organizations across Europe and India. The authors of this paper both lecture in the area of computer networking. Following meetings in Delhi, they agreed to work together to produce a Web-based networking resource to be generated by the students of both institutions. The first phase of development involved the mounting of Web-based tutorials and documents produced by the students. The second phase will centre on the development of a knowledge base generated by the interaction of the students within an asynchronous forum. Running alongside these phases will be a collaborative bookmarking system, a database in which the students will post URLs of Web-based resources that they find useful in their studies. This system incorporates a form of collaborative filtering, an evolutionary mechanism which seeks to embody the qualities that students value in resources to provide a dynamic set of ratings to assist in the selection of those of most use. The planning of such a system raises some unusual issues, not least in the process of collaboration itself, with concerns as diverse as technical compatibility, institutional and cultural differences, timezones and the reliability of email. Limited bandwidth between our institutions causes special problems with the interactive elements of the resource. We present the methods we are investigating to reduce the impact of this. The fact that the students share an intellectual discipline but are otherwise separated by a cultural and geographical divide is expected to lead to fruitful diversity in thinking and approaches to problem-solving.

  2. Modulation of cultured neural networks using neurotrophin release from hydrogel-coated microelectrode arrays

    Science.gov (United States)

    Jun, Sang Beom; Hynd, Matthew R.; Dowell-Mesfin, Natalie M.; Al-Kofahi, Yousef; Roysam, Badrinath; Shain, William; Kim, Sung June

    2008-06-01

    Polyacrylamide and poly(ethylene glycol) diacrylate hydrogels were synthesized and characterized for use as drug release and substrates for neuron cell culture. Protein release kinetics was determined by incorporating bovine serum albumin (BSA) into hydrogels during polymerization. To determine if hydrogel incorporation and release affect bioactivity, alkaline phosphatase was incorporated into hydrogels and a released enzyme activity determined using the fluorescence-based ELF-97 assay. Hydrogels were then used to deliver a brain-derived neurotrophic factor (BDNF) from hydrogels polymerized over planar microelectrode arrays (MEAs). Primary hippocampal neurons were cultured on both control and neurotrophin-containing hydrogel-coated MEAs. The effect of released BDNF on neurite length and process arborization was investigated using automated image analysis. An increased spontaneous activity as a response to the released BDNF was recorded from the neurons cultured on the top of hydrogel layers. These results demonstrate that proteins of biological interest can be incorporated into hydrogels to modulate development and function of cultured neural networks. These results also set the stage for development of hydrogel-coated neural prosthetic devices for local delivery of various biologically active molecules.

  3. Growth-expectations among women entrepreneurs: embedded in networks and culture in Algeria, Morocco, Tunisia and in Belgium and France

    DEFF Research Database (Denmark)

    Cheraghi, Maryam; Setti, Zakia; Schøtt, Thomas

    2014-01-01

    Entrepreneurship Monitor, randomly sampling 39,336 women, including 2,306 entrepreneurs. Analyses show that women entrepreneurs have growth-expectations based on their background and increased by their competence and opportunity-motive, which also promote business networks around their firms. Formation......An entrepreneur usually has an expectation for the firm, expecting expansion, stability or contraction. Expectation is influenced by the entrepreneur's attributes, but expectation is also embedded in the micro-environment of networking and the macro-environment of culture. Traditional culture...... and secular-rational culture differ in roles for women, which influence women entrepreneurs' networking and expectations. The design compares cultures, with data from three traditional societies, Algeria, Morocco and Tunisia and two secular-rational societies, France and Belgium, surveyed in the Global...

  4. OPTIMAL CAMERA NETWORK DESIGN FOR 3D MODELING OF CULTURAL HERITAGE

    Directory of Open Access Journals (Sweden)

    B. S. Alsadik

    2012-07-01

    Full Text Available Digital cultural heritage documentation in 3D is subject to research and practical applications nowadays. Image-based modeling is a technique to create 3D models, which starts with the basic task of designing the camera network. This task is – however – quite crucial in practical applications because it needs a thorough planning and a certain level of expertise and experience. Bearing in mind todays computational (mobile power we think that the optimal camera network should be designed in the field, and, therefore, making the preprocessing and planning dispensable. The optimal camera network is designed when certain accuracy demands are fulfilled with a reasonable effort, namely keeping the number of camera shots at a minimum. In this study, we report on the development of an automatic method to design the optimum camera network for a given object of interest, focusing currently on buildings and statues. Starting from a rough point cloud derived from a video stream of object images, the initial configuration of the camera network assuming a high-resolution state-of-the-art non-metric camera is designed. To improve the image coverage and accuracy, we use a mathematical penalty method of optimization with constraints. From the experimental test, we found that, after optimization, the maximum coverage is attained beside a significant improvement of positional accuracy. Currently, we are working on a guiding system, to ensure, that the operator actually takes the desired images. Further next steps will include a reliable and detailed modeling of the object applying sophisticated dense matching techniques.

  5. The challenges of cross-cultural research and teaching in family medicine: How can professional networks help?

    Directory of Open Access Journals (Sweden)

    Amanda Caroline Howe

    2016-05-01

    Full Text Available Modern medical training emphasizes the value of understanding the patient’s ideas, concerns and expectations, and the use of their personal perspective to assist communication, diagnosis, and uptake of all appropriate health and treatment options. This requires doctors to be ‘culturally sensitive’, which “… involves an awareness and acceptance of cultural differences, self-awareness, knowledge of a patient’s culture, and adaptation of skills”. Yet most of us work in one country, and often one community, for much of our professional careers. Those who enter into academic pursuits will similarly be constrained by our own backgrounds and experiences, even though universities and medical schools often attract a multicultural membership. We therefore rely on our professional training and networks to extend our scope and understanding of how cultural issues impact upon our research and its relevance to our discipline and curricula. This article uses a reflexive narrative approach to examine the role and value of international networks through the lens of one individual and one organisation. It explores the extent to which such networks assist cross cultural sensitivity, using examples from its networks, and how these can (and have impacted on greater cross-culturalism in our teaching and research outputs.

  6. Osteogenic stimulatory conditions enhance growth and maturation of endothelial cell microvascular networks in culture with mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Torbjorn O Pedersen

    2012-12-01

    Full Text Available To optimize culture conditions for in vitro prevascularization of tissue-engineered bone constructs, the development of organotypic blood vessels under osteogenic stimulatory conditions (OM was investigated. Coculture of endothelial cells and mesenchymal stem cells was used to assess proangiogenic effects of mesenchymal stem cells on endothelial cells. Four different culture conditions were evaluated for their effect on development of microvascular endothelial cell networks. Mineralization, deposition of extracellular matrix, and perivascular gene expression were studied in OM. After 3 days, endothelial cells established elongated capillary-like networks, and upregulated expression of vascular markers was seen. After 15 days, all parameters evaluated were significantly increased for cultures in OM. Mature networks developed in OM presented lumens enveloped by basement membrane-like collagen IV, with obvious mineralization and upregulated perivascular gene expression from mesenchymal stem cells. Our results suggest osteogenic stimulatory conditions to be appropriate for in vitro development of vascularized bone implants for tissue engineering.

  7. The Use of Social Networking Sites in Job Related Activities: A Cross-cultural Comparison

    Directory of Open Access Journals (Sweden)

    Małgorzata Bartosik-Purgat

    2017-06-01

    Full Text Available Objective: The main objective of the paper is to identify the use of Social Networking Sites (SNSs in job related activities and indicate the interdependencies between these activities and age, gender, as well as education in culturally diversified markets (China, Poland, Turkey, the United States. Research Design & Methods: In the exploratory empirical study the authors used two research methods: PAPI (Paper and Pen Personal Interview and CAWI (Computer Assisted Web Interview. The empirical data were collected in 2016 and the total number of respondents from four culturally diversified countries was 1246. Findings: The analysis with the use of Kruskal-Wallis and Dunn post-hoc tests showed that the Turkish respondents most often use SNSs for job related activities, while it is the least often done by the studied Americans. Moreover, from among the studied factors (gender, age and education level that differentiate the SNSs usage for job related activities in a statistically significant way age is of greatest importance. Implications & Recommendations: The results of the research provide implications for the recruitment policy of multinational enterprises (MNEs. Since more and more enterprises use SNSs in order to look for new employees and advertise themselves as employers (employer branding, the identified interdependencies between the SNSs activities and the analysed factors can support firm attempts to develop the proper recruitment policy taking into account the cultural diversity of potential workers. Contribution & Value Added: There are not many studies in the literature which present the usage of SNSs for job related activities from the perspective of individual users in the cross-cultural approach. The majority of studies are related to the usage of SNSs by enterprises in the recruitment process.

  8. Neocortical layers I and II of the hedgehog (Erinaceus europaeus). I. Intrinsic organization.

    Science.gov (United States)

    Valverde, F; Facal-Valverde, M V

    1986-01-01

    The intrinsic organization and interlaminar connections in neocortical layers I and II have been studied in adult hedgehogs (Erinaceus europaeus) using the Golgi method. Layer I contains a dense plexus of horizontal fibers, the terminal dendritic bouquets of pyramidal cells of layer II and of underlying layers, and varieties of intrinsic neurons. Four main types of cells were found in layer I. Small horizontal cells represent most probably persisting foetal horizontal cells described for other mammals. Large horizontal cells, tufted cells, and spinous horizontal cells were also found in this layer. Layer II contains primitive pyramidal cells representing the most outstanding feature of the neocortex of the hedgehog. Most pyramidal cells in layer II have two, three or more apical dendrites, richly covered by spines predominating over the basal dendrites. These cells resemble pyramidal cells found in the piriform cortex, hippocampus and other olfactory areas. It is suggested that the presence of these neurons reflects the retention of a primitive character in neocortical evolution. Cells with intrinsic axons were found among pyramidal cells in layer II. These have smooth dendrites penetrating layer I and local axons forming extremely complex terminal arborizations around the bodies and proximal dendritic portions of pyramidal cells. They most probably effect numerous axo-somatic contacts resembling basket cells. The similarity of some axonal terminals with the chandelier type of axonal arborization is discussed. Other varieties of cells located in deep cortical layers and having ascending axons for layers I and II were also studied. It is concluded that the two first neocortical layers represent a level of important integration in this primitive mammal.

  9. Bio-physically plausible visualization of highly scattering fluorescent neocortical models for in silico experimentation

    KAUST Repository

    Abdellah, Marwan

    2017-02-15

    Background We present a visualization pipeline capable of accurate rendering of highly scattering fluorescent neocortical neuronal models. The pipeline is mainly developed to serve the computational neurobiology community. It allows the scientists to visualize the results of their virtual experiments that are performed in computer simulations, or in silico. The impact of the presented pipeline opens novel avenues for assisting the neuroscientists to build biologically accurate models of the brain. These models result from computer simulations of physical experiments that use fluorescence imaging to understand the structural and functional aspects of the brain. Due to the limited capabilities of the current visualization workflows to handle fluorescent volumetric datasets, we propose a physically-based optical model that can accurately simulate light interaction with fluorescent-tagged scattering media based on the basic principles of geometric optics and Monte Carlo path tracing. We also develop an automated and efficient framework for generating dense fluorescent tissue blocks from a neocortical column model that is composed of approximately 31000 neurons. Results Our pipeline is used to visualize a virtual fluorescent tissue block of 50 μm3 that is reconstructed from the somatosensory cortex of juvenile rat. The fluorescence optical model is qualitatively analyzed and validated against experimental emission spectra of different fluorescent dyes from the Alexa Fluor family. Conclusion We discussed a scientific visualization pipeline for creating images of synthetic neocortical neuronal models that are tagged virtually with fluorescent labels on a physically-plausible basis. The pipeline is applied to analyze and validate simulation data generated from neuroscientific in silico experiments.

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

    Science.gov (United States)

    Ingber, Lester

    1984-06-01

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

  11. Designing 3ERP to meet use and users - methods to handle cultural diversity and collaborative networking in SMEs

    DEFF Research Database (Denmark)

    Dirckinck-Holmfeld, Lone; Nielsen, Janni

    2007-01-01

    The purpose is to describe a project the aim of which is to develop and validate the scientific methodological foundation for design of user friendly and usable, flexible and configurable global Enterprise Resource Planning system for Small and Medium sized Enterprises (SMEs) which are adoptable ...... to cultural diversity and support the collaborative networking tasks embedded in 3gERP. Focus is on Human Centered Design methods and tools which must be developed to handle cultural diversity....

  12. CULTURAL ISSUES OF SOCIAL NETWORKS, THEIR PRINCIPLES AND VALUES IN SOCIAL INCLUSION

    Directory of Open Access Journals (Sweden)

    Alessandro Marco Rosini

    2015-09-01

    Full Text Available This article aims to show the importance of a samba school for the local community (in relation to social inclusion and redemption of human values, reflect on the application of this learning created at community to a (organization and discuss the role of people in organizational and cultural strengthening in a social networking environment. It also shows how the use of information technology and communication (ITC can contribute to the evolution of educational scenario of those communities. The scientific method for this is case study, using Delphi technique, where the main community stakeholders are interviewed. Care, respect and consideration for the people who are part of the community are important factors in these social communities. The learning generated by the community and their leaders’ effort are determining for them. ITC can help this learning.

  13. Culture.

    Science.gov (United States)

    Smith, Timothy B; Rodríguez, Melanie Domenech; Bernal, Guillermo

    2011-02-01

    This article summarizes the definitions, means, and research of adapting psychotherapy to clients' cultural backgrounds. We begin by reviewing the prevailing definitions of cultural adaptation and providing a clinical example. We present an original meta-analysis of 65 experimental and quasi-experimental studies involving 8,620 participants. The omnibus effect size of d = .46 indicates that treatments specifically adapted for clients of color were moderately more effective with that clientele than traditional treatments. The most effective treatments tended to be those with greater numbers of cultural adaptations. Mental health services targeted to a specific cultural group were several times more effective than those provided to clients from a variety of cultural backgrounds. We recommend a series of research-supported therapeutic practices that account for clients' culture, with culture-specific treatments being more effective than generally culture-sensitive treatments. © 2010 Wiley Periodicals, Inc.

  14. Women Favour Dyadic Relationships, but Men Prefer Clubs: Cross-Cultural Evidence from Social Networking

    Science.gov (United States)

    David-Barrett, Tamas; Rotkirch, Anna; Carney, James; Behncke Izquierdo, Isabel; Krems, Jaimie A.; Townley, Dylan; McDaniell, Elinor; Byrne-Smith, Anna; Dunbar, Robin I. M.

    2015-01-01

    The ability to create lasting, trust-based friendships makes it possible for humans to form large and coherent groups. The recent literature on the evolution of sociality and on the network dynamics of human societies suggests that large human groups have a layered structure generated by emotionally supported social relationships. There are also gender differences in adult social style which may involve different trade-offs between the quantity and quality of friendships. Although many have suggested that females tend to focus on intimate relations with a few other females, while males build larger, more hierarchical coalitions, the existence of such gender differences is disputed and data from adults is scarce. Here, we present cross-cultural evidence for gender differences in the preference for close friendships. We use a sample of ∼112,000 profile pictures from nine world regions posted on a popular social networking site to show that, in self-selected displays of social relationships, women favour dyadic relations, whereas men favour larger, all-male cliques. These apparently different solutions to quality-quantity trade-offs suggest a universal and fundamental difference in the function of close friendships for the two sexes. PMID:25775258

  15. Women favour dyadic relationships, but men prefer clubs: cross-cultural evidence from social networking.

    Directory of Open Access Journals (Sweden)

    Tamas David-Barrett

    Full Text Available The ability to create lasting, trust-based friendships makes it possible for humans to form large and coherent groups. The recent literature on the evolution of sociality and on the network dynamics of human societies suggests that large human groups have a layered structure generated by emotionally supported social relationships. There are also gender differences in adult social style which may involve different trade-offs between the quantity and quality of friendships. Although many have suggested that females tend to focus on intimate relations with a few other females, while males build larger, more hierarchical coalitions, the existence of such gender differences is disputed and data from adults is scarce. Here, we present cross-cultural evidence for gender differences in the preference for close friendships. We use a sample of ∼112,000 profile pictures from nine world regions posted on a popular social networking site to show that, in self-selected displays of social relationships, women favour dyadic relations, whereas men favour larger, all-male cliques. These apparently different solutions to quality-quantity trade-offs suggest a universal and fundamental difference in the function of close friendships for the two sexes.

  16. Barbed channels enhance unidirectional connectivity between neuronal networks cultured on multi electrode arrays

    Science.gov (United States)

    le Feber, Joost; Postma, Wybren; de Weerd, Eddy; Weusthof, Marcel; Rutten, Wim L. C.

    2015-01-01

    Cultured neurons on multi electrode arrays (MEAs) have been widely used to study various aspects of neuronal (network) functioning. A possible drawback of this approach is the lack of structure in these networks. At the single cell level, several solutions have been proposed to enable directed connectivity, and promising results were obtained. At the level of connected sub-populations, a few attempts have been made with promising results. First assessment of the designs' functionality, however, suggested room for further improvement. We designed a two chamber MEA aiming to create a unidirectional connection between the networks in both chambers (“emitting” and “receiving”). To achieve this unidirectionality, all interconnecting channels contained barbs that hindered axon growth in the opposite direction (from receiving to emitting chamber). Visual inspection showed that axons predominantly grew through the channels in the promoted direction. This observation was confirmed by spontaneous activity recordings. Cross-correlation between the signals from two electrodes inside the channels suggested signal propagation at ≈2 m/s from emitting to receiving chamber. Cross-correlation between the firing patterns in both chambers indicated that most correlated activity was initiated in the emitting chamber, which was also reflected by a significantly lower fraction of partial bursts (i.e., a one-chamber-only burst) in the emitting chamber. Finally, electrical stimulation in the emitting chamber induced a fast response in that chamber, and a slower response in the receiving chamber. Stimulation in the receiving chamber evoked a fast response in that chamber, but no response in the emitting chamber. These results confirm the predominantly unidirectional nature of the connecting channels from emitting to receiving chamber. PMID:26578869

  17. Barbed channels enhance unidirectional connectivity between neuronal networks cultured on multi electrode arrays.

    Directory of Open Access Journals (Sweden)

    Joost eLe Feber

    2015-11-01

    Full Text Available Cultured neurons on multi electrode arrays (MEAs have been widely used to study various as-pects of neuronal (network functioning. A possible drawback of this approach is the lack of structure in these networks. At the single cell level, several solutions have been proposed to ena-ble directed connectivity, and promising results were obtained. At the level of connected sub-populations, a few attempts have been made with promising results. First assessment of the de-signs’ functionality, however, suggested room for further improvement.We designed a two chamber MEA aiming to create a unidirectional connection between the net-works in both chambers (‘emitting’ and ‘receiving’. To achieve this unidirectionality, all inter-connecting channels contained barbs that hindered axon growth in the opposite direction (from receiving to emitting chamber. Visual inspection showed that axons predominantly grew through the channels in the promoted direction . This observation was confirmed by spontaneous activity recordings. Cross-correlation between the signals from two electrodes inside the channels suggested signal propagation at ≈2 m/s from emitting to receiving chamber. Cross-correlation between the firing patterns in both chambers indicated that most correlated activity was initiated in the emitting chamber, which was also reflected by a significantly lower fraction of partial bursts (e. a one-chamber-only burst in the emitting chamber. Finally, electrical stimulation in the emitting chamber induced a fast response in that chamber, and a slower response in the receiving chamber. Stimulation in the receiving chamber evoked a fast response in that chamber, but no response in the emitting chamber. These results confirm the predominantly unidirectional nature of the connecting channels from emitting to receiving chamber.

  18. GABA action in immature neocortical neurons directly depends on the availability of ketone bodies.

    Science.gov (United States)

    Rheims, Sylvain; Holmgren, Carl D; Chazal, Genevieve; Mulder, Jan; Harkany, Tibor; Zilberter, Tanya; Zilberter, Yuri

    2009-08-01

    In the early postnatal period, energy metabolism in the suckling rodent brain relies to a large extent on metabolic pathways alternate to glucose such as the utilization of ketone bodies (KBs). However, how KBs affect neuronal excitability is not known. Using recordings of single NMDA and GABA-activated channels in neocortical pyramidal cells we studied the effects of KBs on the resting membrane potential (E(m)) and reversal potential of GABA-induced anionic currents (E(GABA)), respectively. We show that during postnatal development (P3-P19) if neocortical brain slices are adequately supplied with KBs, E(m) and E(GABA) are both maintained at negative levels of about -83 and -80 mV, respectively. Conversely, a KB deficiency causes a significant depolarization of both E(m) (>5 mV) and E(GABA) (>15 mV). The KB-mediated shift in E(GABA) is largely determined by the interaction of the NKCC1 cotransporter and Cl(-)/HCO3 transporter(s). Therefore, by inducing a hyperpolarizing shift in E(m) and modulating GABA signaling mode, KBs can efficiently control the excitability of neonatal cortical neurons.

  19. Melatonin administration impairs visuo-spatial performance and inhibits neocortical long-term potentiation in rats.

    Science.gov (United States)

    Soto-Moyano, Rubén; Burgos, Héctor; Flores, Francisco; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Pérez, Hernán; Hernández, Paula; Hernández, Alejandro

    2006-10-01

    Melatonin has been shown to inhibit long-term potentiation (LTP) in hippocampal slices of rats. Since LTP may be one of the main mechanisms by which memory traces are encoded and stored in the central nervous system, it is possible that melatonin could modulate cognitive performance by interfering with the cellular and/or molecular mechanisms involved in LTP. We investigated in rats the effects of intraperitoneally-administered melatonin (0.1, 1 and 10 mg/kg), its saline-ethanol solvent, or saline alone, on the acquisition of visuo-spatial memory as well as on the ability of the cerebral cortex to develop LTP in vivo. Visuo-spatial performance was assessed daily in rats, for 10 days, in an 8-arm radial maze, 30 min after they received a single daily dose of melatonin. Visual cortex LTP was determined in sodium pentobarbital anesthetized rats (65 mg/kg i.p.), by potentiating transcallosal evoked responses with a tetanizing train (312 Hz, 500 ms duration) 30 min after administration of a single dose of melatonin. Results showed that melatonin impaired visuo-spatial performance in rats, as revealed by the greater number of errors committed and time spent to solve the task in the radial maze. Melatonin also prevented the induction of neocortical LTP. It is concluded that melatonin, at the doses utilized in this study, could alter some forms of neocortical plasticity involved in short- and long-term visuo-spatial memories in rats.

  20. Neural mechanisms of transient neocortical beta rhythms: Converging evidence from humans, computational modeling, monkeys, and mice

    Science.gov (United States)

    Sherman, Maxwell A.; Lee, Shane; Law, Robert; Haegens, Saskia; Thorn, Catherine A.; Hämäläinen, Matti S.; Moore, Christopher I.; Jones, Stephanie R.

    2016-01-01

    Human neocortical 15–29-Hz beta oscillations are strong predictors of perceptual and motor performance. However, the mechanistic origin of beta in vivo is unknown, hindering understanding of its functional role. Combining human magnetoencephalography (MEG), computational modeling, and laminar recordings in animals, we present a new theory that accounts for the origin of spontaneous neocortical beta. In our MEG data, spontaneous beta activity from somatosensory and frontal cortex emerged as noncontinuous beta events typically lasting drive targeting proximal and distal dendrites of pyramidal neurons, where the defining feature of a beta event was a strong distal drive that lasted one beta period (∼50 ms). This beta mechanism rigorously accounted for the beta event profiles; several other mechanisms did not. The spatial location of synaptic drive in the model to supragranular and infragranular layers was critical to the emergence of beta events and led to the prediction that beta events should be associated with a specific laminar current profile. Laminar recordings in somatosensory neocortex from anesthetized mice and awake monkeys supported these predictions, suggesting this beta mechanism is conserved across species and recording modalities. These findings make several predictions about optimal states for perceptual and motor performance and guide causal interventions to modulate beta for optimal function. PMID:27469163

  1. Volumetric MRI for evaluation of regional pattern and progression of neocortical degeneration in Alzheimer's disease

    International Nuclear Information System (INIS)

    Leinsinger, G.; Teipel, S.; Pruessner, J.; Hampel, H.; Wismueller, A.; Born, C.; Meindl, T.; Flatz, W.; Schoenberg, S.; Reiser, M.

    2003-01-01

    Volumetric analysis of the corpus callosum and hippocampus using MRI in Alzheimer's disease (AD) to evaluate the regional pattern and progression of neocortical neurodegeneration. In subsequent studies we investigated patients with AD and healthy controls. Volumetry was based on MRI-data from a sagittal 3D T1w-gradient echo sequence. The corpus callosum (CC) was measured in a midsagittal slice, and subdivided into 5 subregions. Volumetry of the hippocampus/amygdala-formation (HAF) was performed by segmentation in coronary reoriented slices. In AD patients we found a significant atrophy in the rostrum und splenium of CC. The atrophy was correlated with the severity of dementia, but no correlation was found with the load of white matter lesions. In comparison with 18 FDG-PET, we found a significant correlation of regional CC-atrophy with the regional decline of cortical glucose metabolism. A ROC-analysis demonstrated no significant differences in the diagostic accuracy of HAF volumetry and regional CC volumetry of the splenium (region C5) even in mild stages of dementia. Regional atrophy of CC can be used as a marker of neocortical degeneration even in early stages of dementia in AD. (orig.) [de

  2. Layer-specific morphological and molecular differences in neocortical astrocytes and their dependence on neuronal layers.

    Science.gov (United States)

    Lanjakornsiripan, Darin; Pior, Baek-Jun; Kawaguchi, Daichi; Furutachi, Shohei; Tahara, Tomoaki; Katsuyama, Yu; Suzuki, Yutaka; Fukazawa, Yugo; Gotoh, Yukiko

    2018-04-24

    Non-pial neocortical astrocytes have historically been thought to comprise largely a nondiverse population of protoplasmic astrocytes. Here we show that astrocytes of the mouse somatosensory cortex manifest layer-specific morphological and molecular differences. Two- and three-dimensional observations revealed that astrocytes in the different layers possess distinct morphologies as reflected by differences in cell orientation, territorial volume, and arborization. The extent of ensheathment of synaptic clefts by astrocytes in layer II/III was greater than that by those in layer VI. Moreover, differences in gene expression were observed between upper-layer and deep-layer astrocytes. Importantly, layer-specific differences in astrocyte properties were abrogated in reeler and Dab1 conditional knockout mice, in which neuronal layers are disturbed, suggesting that neuronal layers are a prerequisite for the observed morphological and molecular differences of neocortical astrocytes. This study thus demonstrates the existence of layer-specific interactions between neurons and astrocytes, which may underlie their layer-specific functions.

  3. Cultural specificity of socioemotional selectivity: age differences in social network composition among Germans and Hong Kong Chinese.

    Science.gov (United States)

    Fung, Helene H; Stoeber, Franziska S; Yeung, Dannii Yuen-lan; Lang, Frieder R

    2008-05-01

    We examined age differences in social network composition among 330 Germans and 330 Hong Kong Chinese, aged 20 to 91 years. We measured social network composition with the Social Convoy Questionnaire. In both cultures, older age was associated with the same number of close social partners and fewer peripheral social partners than was younger age. However, the patterns of age differences in specific relationships differed across cultures: Age was negatively associated with the proportion of nuclear family members among Germans but the association was positive among Hong Kong Chinese. Age was positively associated with the proportion of acquaintances among Germans but the association was negative among Hong Kong Chinese. We discuss the findings in terms of whether the socioemotional selectivity theory holds in both cultures.

  4. Networks, narratives and territory in anthropological race classification: towards a more comprehensive historical geography of Europe's culture.

    Science.gov (United States)

    McMahon, Richard

    2011-01-01

    This article aims to integrate discourse analysis of politically instrumental imagined identity geographies with the relational and territorial geography of the communities of praxis and interpretation that produce them. My case study is the international community of nationalist scientists who classified Europe's biological races in the 1820s-1940s. I draw on network analysis, relational geography, historical sociology and the historical turn to problematize empirically how spatial patterns of this community's shifting disciplinary and political coalitions, communication networks and power relations emerged, were structured, persisted, changed, interacted and disappeared. I focus especially on core-periphery relations. I argue that if local historical spatial patterns affect those of later phenomena, geographies like that of European integration should be understood in the context of Europe's complex historical cultural geography. Unlike discourse deconstruction alone, this complementary relational de-essentialization of geography can identify large-scale, enduring associations of cultural patterns as well as cultural flux and ambiguity.

  5. Resection of individually identified high-rate high-frequency oscillations region is associated with favorable outcome in neocortical epilepsy

    Czech Academy of Sciences Publication Activity Database

    Cho, J.R.; Koo, D.L.; Joo, E.Y.; Seo, D.W.; Hong, S.-Ch.; Jiruška, Přemysl; Hong, S.B.

    2014-01-01

    Roč. 55, č. 11 (2014), s. 1872-1883 ISSN 0013-9580 R&D Projects: GA MZd(CZ) NT14489 Institutional support: RVO:67985823 Keywords : epilepsy surgery * high-frequency oscillations * neocortical epilepsy Subject RIV: FH - Neurology Impact factor: 4.571, year: 2014

  6. Structural-functional connectivity deficits of neocortical circuits in the Fmr1 (-/y) mouse model of autism

    NARCIS (Netherlands)

    Haberl, M.G.; Zerbi, V.; Veltien, A.A.; Ginger, M.; Heerschap, A.; Frick, A.

    2015-01-01

    Fragile X syndrome (FXS), the most common inherited form of intellectual disability disorder and a frequent cause of autism spectrum disorder (ASD), is characterized by a high prevalence of sensory symptoms. Perturbations in the anatomical connectivity of neocortical circuits resulting in their

  7. Response of Cultured Neuronal Network Activity After High-Intensity Power Frequency Magnetic Field Exposure

    Directory of Open Access Journals (Sweden)

    Atsushi Saito

    2018-03-01

    Full Text Available High-intensity and low frequency (1–100 kHz time-varying electromagnetic fields stimulate the human body through excitation of the nervous system. In power frequency range (50/60 Hz, a frequency-dependent threshold of the external electric field-induced neuronal modulation in cultured neuronal networks was used as one of the biological indicator in international guidelines; however, the threshold of the magnetic field-induced neuronal modulation has not been elucidated. In this study, we exposed rat brain-derived neuronal networks to a high-intensity power frequency magnetic field (hPF-MF, and evaluated the modulation of synchronized bursting activity using a multi-electrode array (MEA-based extracellular recording technique. As a result of short-term hPF-MF exposure (50–400 mT root-mean-square (rms, 50 Hz, sinusoidal wave, 6 s, the synchronized bursting activity was increased in the 400 mT-exposed group. On the other hand, no change was observed in the 50–200 mT-exposed groups. In order to clarify the mechanisms of the 400 mT hPF-MF exposure-induced neuronal response, we evaluated it after blocking inhibitory synapses using bicuculline methiodide (BMI; subsequently, increase in bursting activity was observed with BMI application, and the response of 400 mT hPF-MF exposure disappeared. Therefore, it was suggested that the response of hPF-MF exposure was involved in the inhibitory input. Next, we screened the inhibitory pacemaker-like neuronal activity which showed autonomous 4–10 Hz firing with CNQX and D-AP5 application, and it was confirmed that the activity was reduced after 400 mT hPF-MF exposure. Comparison of these experimental results with estimated values of the induced electric field (E-field in the culture medium revealed that the change in synchronized bursting activity occurred over 0.3 V/m, which was equivalent to the findings of a previous study that used the external electric fields. In addition, the results suggested that

  8. Automated Interpretation of Blood Culture Gram Stains by Use of a Deep Convolutional Neural Network.

    Science.gov (United States)

    Smith, Kenneth P; Kang, Anthony D; Kirby, James E

    2018-03-01

    Microscopic interpretation of stained smears is one of the most operator-dependent and time-intensive activities in the clinical microbiology laboratory. Here, we investigated application of an automated image acquisition and convolutional neural network (CNN)-based approach for automated Gram stain classification. Using an automated microscopy platform, uncoverslipped slides were scanned with a 40× dry objective, generating images of sufficient resolution for interpretation. We collected 25,488 images from positive blood culture Gram stains prepared during routine clinical workup. These images were used to generate 100,213 crops containing Gram-positive cocci in clusters, Gram-positive cocci in chains/pairs, Gram-negative rods, or background (no cells). These categories were targeted for proof-of-concept development as they are associated with the majority of bloodstream infections. Our CNN model achieved a classification accuracy of 94.9% on a test set of image crops. Receiver operating characteristic (ROC) curve analysis indicated a robust ability to differentiate between categories with an area under the curve of >0.98 for each. After training and validation, we applied the classification algorithm to new images collected from 189 whole slides without human intervention. Sensitivity and specificity were 98.4% and 75.0% for Gram-positive cocci in chains and pairs, 93.2% and 97.2% for Gram-positive cocci in clusters, and 96.3% and 98.1% for Gram-negative rods. Taken together, our data support a proof of concept for a fully automated classification methodology for blood-culture Gram stains. Importantly, the algorithm was highly adept at identifying image crops with organisms and could be used to present prescreened, classified crops to technologists to accelerate smear review. This concept could potentially be extended to all Gram stain interpretive activities in the clinical laboratory. Copyright © 2018 American Society for Microbiology.

  9. Multiple non-cell-autonomous defects underlie neocortical callosal dysgenesis in Nfib-deficient mice

    Directory of Open Access Journals (Sweden)

    Sunn Nana

    2009-12-01

    Full Text Available Abstract Background Agenesis of the corpus callosum is associated with many human developmental syndromes. Key mechanisms regulating callosal formation include the guidance of axons arising from pioneering neurons in the cingulate cortex and the development of cortical midline glial populations, but their molecular regulation remains poorly characterised. Recent data have shown that mice lacking the transcription factor Nfib exhibit callosal agenesis, yet neocortical callosal neurons express only low levels of Nfib. Therefore, we investigate here how Nfib functions to regulate non-cell-autonomous mechanisms of callosal formation. Results Our investigations confirmed a reduction in glial cells at the midline in Nfib-/- mice. To determine how this occurs, we examined radial progenitors at the cortical midline and found that they were specified correctly in Nfib mutant mice, but did not differentiate into mature glia. Cellular proliferation and apoptosis occurred normally at the midline of Nfib mutant mice, indicating that the decrease in midline glia observed was due to deficits in differentiation rather than proliferation or apoptosis. Next we investigated the development of callosal pioneering axons in Nfib-/- mice. Using retrograde tracer labelling, we found that Nfib is expressed in cingulate neurons and hence may regulate their development. In Nfib-/- mice, neuropilin 1-positive axons fail to cross the midline and expression of neuropilin 1 is diminished. Tract tracing and immunohistochemistry further revealed that, in late gestation, a minor population of neocortical axons does cross the midline in Nfib mutants on a C57Bl/6J background, forming a rudimentary corpus callosum. Finally, the development of other forebrain commissures in Nfib-deficient mice is also aberrant. Conclusion The formation of the corpus callosum is severely delayed in the absence of Nfib, despite Nfib not being highly expressed in neocortical callosal neurons. Our

  10. Damaged Neocortical Perineuronal Nets Due to Experimental Focal Cerebral Ischemia in Mice, Rats and Sheep

    Directory of Open Access Journals (Sweden)

    Wolfgang Härtig

    2017-08-01

    Full Text Available As part of the extracellular matrix (ECM, perineuronal nets (PNs are polyanionic, chondroitin sulfate proteoglycan (CSPG-rich coatings of certain neurons, known to be affected in various neural diseases. Although these structures are considered as important parts of the neurovascular unit (NVU, their role during evolution of acute ischemic stroke and subsequent tissue damage is poorly understood and only a few preclinical studies analyzed PNs after acute ischemic stroke. By employing three models of experimental focal cerebral ischemia, this study was focused on histopathological alterations of PNs and concomitant vascular, glial and neuronal changes according to the NVU concept. We analyzed brain tissues obtained 1 day after ischemia onset from: (a mice after filament-based permanent middle cerebral artery occlusion (pMCAO; (b rats subjected to thromboembolic MACO; and (c sheep at 14 days after electrosurgically induced focal cerebral ischemia. Multiple fluorescence labeling was applied to explore simultaneous alterations of NVU and ECM. Serial mouse sections labeled with the net marker Wisteria floribunda agglutinin (WFA displayed largely decomposed and nearly erased PNs in infarcted neocortical areas that were demarcated by up-regulated immunoreactivity for vascular collagen IV (Coll IV. Subsequent semi-quantitative analyses in mice confirmed significantly decreased WFA-staining along the ischemic border zone and a relative decrease in the directly ischemia-affected neocortex. Triple fluorescence labeling throughout the three animal models revealed up-regulated Coll IV and decomposed PNs accompanied by activated astroglia and altered immunoreactivity for parvalbumin, a calcium-binding protein in fast-firing GABAergic neurons which are predominantly surrounded by neocortical PNs. Furthermore, ischemic neocortical areas in rodents simultaneously displayed less intense staining of WFA, aggrecan, the net components neurocan, versican and the

  11. Identifying socio-ecological networks in rural-urban gradients: Diagnosis of a changing cultural landscape.

    Science.gov (United States)

    Arnaiz-Schmitz, C; Schmitz, M F; Herrero-Jáuregui, C; Gutiérrez-Angonese, J; Pineda, F D; Montes, C

    2018-01-15

    Socio-ecological systems maintain reciprocal interactions between biophysical and socioeconomic structures. As a result of these interactions key essential services for society emerge. Urban expansion is a direct driver of land change and cause serious shifts in socio-ecological relationships and the associated lifestyles. The framework of rural-urban gradients has proved to be a powerful tool for ecological research about urban influences on ecosystems and on sociological issues related to social welfare. However, to date there has not been an attempt to achieve a classification of municipalities in rural-urban gradients based on socio-ecological interactions. In this paper, we developed a methodological approach that allows identifying and classifying a set of socio-ecological network configurations in the Region of Madrid, a highly dynamic cultural landscape considered one of the European hotspots in urban development. According to their socio-ecological links, the integrated model detects four groups of municipalities, ordered along a rural-urban gradient, characterized by their degree of biophysical and socioeconomic coupling and different indicators of landscape structure and social welfare. We propose the developed model as a useful tool to improve environmental management schemes and land planning from a socio-ecological perspective, especially in territories subject to intense urban transformations and loss of rurality. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Digital media sport technology, power and culture in the network society

    CERN Document Server

    Hutchins, Brett; Morris, Peter; Therivel, Riki

    2013-01-01

    Live broadband streaming of the 2008 Beijing Olympics accounted for 2,200 of the estimated 3,600 total hours shown by the American NBC-Universal networks. At the 2012 London Olympics, unprecedented multi-platforming embraced online, mobile devices, game consoles and broadcast television, with the BBC providing 2,500 hours of live coverage, including every competitive event, much in high definition and some in 3D. The BBC also had 12 million requests for video on mobile phones and 9.2 million browsers on its mobile Olympics website and app. This pattern will only intensify at future sport mega events like the 2014 FIFA World Cup and 2016 Summer Olympics, both of which will take place in Brazil. Increasingly, when people talk of the screen that delivers footage of their favorite professional sport, they are describing desktop, laptop, and tablet computer screens as well as television and mobile handsets. Digital Media Sport analyzes the intersecting issues of technological change, market power, and cultural pra...

  13. THE PAN AFRICAN E-NETWORK PROJECT: A New Learning Culture

    Directory of Open Access Journals (Sweden)

    Nundoo-Ghoorah SUNITI

    2012-07-01

    Full Text Available This paper sets out to explore the paradigm shift in learning culture brought about by the advent of online learning in the mostly print-based ODL system at the Mauritius College of the Air (MCA. It delves into the perceptions of learners and MCA staff involved in a range of undergraduate to Master’s programmes forming part of the Pan African e- Network Project that wires 23 African countries with top-ranking Indian universities through synchronous and interactive state of the art technology. Learners across five of the disciplines offered through tele-learning and a team of MCA staff participating in programme delivery were surveyed through questionnaires and interviews to collect both quantitative and qualitative data. For most of the respondents this new learning ethos has induced an acculturation process requiring radical reconceptualisation of prior notions about teaching/learning. MCA staff, too, have had to learn conducive behavior patterns to consolidate existing support services. Survival in this new learning environment where the tutor is a remote on-screen entity, where e-books replace printed material, where connectivity can be a daily struggle, demands another mindset, another set of values enabling learning and fine-tuned ICT skills. Socialisation with tutors and fellow learners is possible through links in Facebook and Twitter. However, learners still tend to feel somewhat isolated. It is proposed that an e-platform be set up to link up learners as a mutually supportive learning community engaged in the construction of knowledge.

  14. The Influence of Culture on the Expression of Emotions in Online Social Networks

    Directory of Open Access Journals (Sweden)

    Cathia PAPI

    2016-12-01

    Full Text Available Seeking to understand the influence of culture on the expression of emotions in online social networks, we analyzed four Facebook groups – two from Quebec, Canada and two from Colombia – created following unexpected deaths. Comparison of the messages posted in these groups reveals a stronger tendency to maintain a virtual relationship with the deceased by Canadians than by Columbians. Among the former, the deceased is more often asked to and thanked for watching over the living, and testimonies of love addressed to the deceased are more numerous than among the latter. Among the latter, the strength of the links maintained with the deceased justifying the present pain and evocation of the mourners’ Catholic beliefs are relatively more frequent. Finally, while the Canadian Quebecers’ messages would presumably be written in French and those of Colombians in Spanish, it is interesting to observe a certain presence of English to express feelings of loss and love in the four groups, as well as a certain affinity between North American virtual bereavement practices and those seemingly more characteristic of women, the main contributors in all four groups.

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

    Science.gov (United States)

    Ingber, Lester

    1994-05-01

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

  16. Hyperconnectivity of local neocortical microcircuitry induced by prenatal exposure to valproic acid

    DEFF Research Database (Denmark)

    Rinaldi, Tania; Silberberg, Gilad; Markram, Henry

    2008-01-01

    Exposure to valproic acid (VPA) during embryogenesis can cause several teratogenic effects, including developmental delays and in particular autism in humans if exposure occurs during the third week of gestation. We examined the postnatal effects of embryonic exposure to VPA on microcircuit...... properties of juvenile rat neocortex using in vitro electrophysiology. We found that a single prenatal injection of VPA on embryonic day 11.5 causes a significant enhancement of the local recurrent connectivity formed by neocortical pyramidal neurons. The study of the biophysical properties...... of these connections revealed weaker excitatory synaptic responses. A marked decrease of the intrinsic excitability of pyramidal neurons was also observed. Furthermore, we demonstrate a diminished number of putative synaptic contacts in connection between layer 5 pyramidal neurons. Local hyperconnectivity may render...

  17. Prdm8 regulates the morphological transition at multipolar phase during neocortical development.

    Directory of Open Access Journals (Sweden)

    Mayuko Inoue

    Full Text Available Here, we found that the PR domain protein Prdm8 serves as a key regulator of the length of the multipolar phase by controlling the timing of morphological transition. We used a mouse line with expression of Prdm8-mVenus reporter and found that Prdm8 is predominantly expressed in the middle and upper intermediate zone during both the late and terminal multipolar phases. Prdm8 expression was almost coincident with Unc5D expression, a marker for the late multipolar phase, although the expression of Unc5D was found to be gradually down-regulated to the point at which mVenus expression was gradually up-regulated. This expression pattern suggests the possible involvement of Prdm8 in the control of the late and terminal multipolar phases, which controls the timing for morphological transition. To test this hypothesis, we performed gain- and loss-of-function analysis of neocortical development by using in utero electroporation. We found that the knockdown of Prdm8 results in premature change from multipolar to bipolar morphology, whereas the overexpression of Prdm8 maintained the multipolar morphology. Additionally, the postnatal analysis showed that the Prdm8 knockdown stimulated the number of early born neurons, and differentiated neurons located more deeply in the neocortex, however, majority of those cells could not acquire molecular features consistent with laminar location. Furthermore, we found the candidate genes that were predominantly utilized in both the late and terminal multipolar phases, and these candidate genes included those encoding for guidance molecules. In addition, we also found that the expression level of these guidance molecules was inhibited by the introduction of the Prdm8 expression vector. These results indicate that the Prdm8-mediated regulation of morphological changes that normally occur during the late and terminal multipolar phases plays an important role in neocortical development.

  18. Effects of Cultural Tightness-Looseness and Social Network Density on Expression of Positive and Negative Emotions: A Large-Scale Study of Impression Management by Facebook Users.

    Science.gov (United States)

    Liu, Pan; Chan, David; Qiu, Lin; Tov, William; Tong, Victor Joo Chuan

    2018-05-01

    Using data from 13,789 Facebook users across U.S. states, this study examined the main effects of societal-level cultural tightness-looseness and its interaction effects with individuals' social network density on impression management (IM) in terms of online emotional expression. Results showed that individuals from culturally tight (vs. loose) states were more likely to express positive emotions and less likely to express negative emotions. Meanwhile, for positive emotional expression, there was a tightness-looseness by social network density interaction effect. In culturally tight states, individuals with dense (vs. sparse) networks were more likely to express positive emotions, while in culturally loose states this pattern was reversed. For negative emotional expression, however, no such interaction was observed. Our findings highlight the influence of cultural norms and social network structure on emotional expressions as IM strategies.

  19. Artificial neural network-based model for the prediction of optimal growth and culture conditions for maximum biomass accumulation in multiple shoot cultures of Centella asiatica.

    Science.gov (United States)

    Prasad, Archana; Prakash, Om; Mehrotra, Shakti; Khan, Feroz; Mathur, Ajay Kumar; Mathur, Archana

    2017-01-01

    An artificial neural network (ANN)-based modelling approach is used to determine the synergistic effect of five major components of growth medium (Mg, Cu, Zn, nitrate and sucrose) on improved in vitro biomass yield in multiple shoot cultures of Centella asiatica. The back propagation neural network (BPNN) was employed to predict optimal biomass accumulation in terms of growth index over a defined culture duration of 35 days. The four variable concentrations of five media components, i.e. MgSO 4 (0, 0.75, 1.5, 3.0 mM), ZnSO 4 (0, 15, 30, 60 μM), CuSO 4 (0, 0.05, 0.1, 0.2 μM), NO 3 (20, 30, 40, 60 mM) and sucrose (1, 3, 5, 7 %, w/v) were taken as inputs for the ANN model. The designed model was evaluated by performing three different sets of validation experiments that indicated a greater similarity between the target and predicted dataset. The results of the modelling experiment suggested that 1.5 mM Mg, 30 μM Zn, 0.1 μM Cu, 40 mM NO 3 and 6 % (w/v) sucrose were the respective optimal concentrations of the tested medium components for achieving maximum growth index of 1654.46 with high centelloside yield (62.37 mg DW/culture) in the cultured multiple shoots. This study can facilitate the generation of higher biomass of uniform, clean, good quality C. asiatica herb that can efficiently be utilized by pharmaceutical industries.

  20. How the Internet Facilitates the Activity within a Consumer Culture : - A Study of the Online Vinyl Record Network

    OpenAIRE

    Söderlindh, Stefan; Broman, David

    2009-01-01

    The purpose of this thesis is to describe and analyze how the online vinyl record network functions from both a consumer and retailer perspective, in order to gain an understanding of how the Internet facilitates the activity within a consumer culture. The vinyl record industry is experiencing a revival, with an upswing in sales and media attention and a significant increase in the amount of online trading. This inductive study contains data from qualitative interviews with ten vinyl record c...

  1. The Power of Social Networks: A Model for Weaving the Scholarship of Teaching and Learning into Institutional Culture

    Directory of Open Access Journals (Sweden)

    Andrea L. Williams

    2013-09-01

    micro, the meso, and the macro. The authors argue that for SoTL to take root in organizational cultures, there must be 1 effective communication and dissemination of SoTL activity across all levels, 2 well established social networks and links between these levels (nodes, and 3 sustained support by senior administrationThe authors conclude by suggesting ways their model could be tested.

  2. Development of an Evaluation Method for Team Safety Culture Competencies using Social Network Analysis

    International Nuclear Information System (INIS)

    Han, Sang Min; Kim, Ar Ryum; Seong, Poong Hyun

    2016-01-01

    In this study, team safety culture competency of a team was estimated through SNA, as a team safety culture index. To overcome the limit of existing safety culture evaluation methods, the concept of competency and SNA were adopted. To estimate team safety culture competency, we defined the definition, range and goal of team safety culture competencies. Derivation of core team safety culture competencies is performed and its behavioral characteristics were derived for each safety culture competency, from the procedures used in NPPs and existing criteria to assess safety culture. Then observation was chosen as a method to provide the input data for the SNA matrix of team members versus insufficient team safety culture competencies. Then through matrix operation, the matrix was converted into the two meaningful values, which are density of team members and degree centralities of each team safety culture competency. Density of tem members and degree centrality of each team safety culture competency represent the team safety culture index and the priority of team safety culture competency to be improved

  3. Development of an Evaluation Method for Team Safety Culture Competencies using Social Network Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Min; Kim, Ar Ryum; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    In this study, team safety culture competency of a team was estimated through SNA, as a team safety culture index. To overcome the limit of existing safety culture evaluation methods, the concept of competency and SNA were adopted. To estimate team safety culture competency, we defined the definition, range and goal of team safety culture competencies. Derivation of core team safety culture competencies is performed and its behavioral characteristics were derived for each safety culture competency, from the procedures used in NPPs and existing criteria to assess safety culture. Then observation was chosen as a method to provide the input data for the SNA matrix of team members versus insufficient team safety culture competencies. Then through matrix operation, the matrix was converted into the two meaningful values, which are density of team members and degree centralities of each team safety culture competency. Density of tem members and degree centrality of each team safety culture competency represent the team safety culture index and the priority of team safety culture competency to be improved.

  4. A spatially resolved network spike in model neuronal cultures reveals nucleation centers, circular traveling waves and drifting spiral waves.

    Science.gov (United States)

    Paraskevov, A V; Zendrikov, D K

    2017-03-23

    We show that in model neuronal cultures, where the probability of interneuronal connection formation decreases exponentially with increasing distance between the neurons, there exists a small number of spatial nucleation centers of a network spike, from where the synchronous spiking activity starts propagating in the network typically in the form of circular traveling waves. The number of nucleation centers and their spatial locations are unique and unchanged for a given realization of neuronal network but are different for different networks. In contrast, if the probability of interneuronal connection formation is independent of the distance between neurons, then the nucleation centers do not arise and the synchronization of spiking activity during a network spike occurs spatially uniform throughout the network. Therefore one can conclude that spatial proximity of connections between neurons is important for the formation of nucleation centers. It is also shown that fluctuations of the spatial density of neurons at their random homogeneous distribution typical for the experiments in vitro do not determine the locations of the nucleation centers. The simulation results are qualitatively consistent with the experimental observations.

  5. Altered Loyalties of Neuronal Markers in Cultured Slices of Resected Human Brain Tissue

    NARCIS (Netherlands)

    Verwer, Ronald W. H.; Sluiter, Arja A.; Balesar, Rawien A.; Baayen, Johannes C.; Speijer, Dave; Idema, Sander; Swaab, Dick F.

    2016-01-01

    Organotypic cultures from normal neocortical tissue obtained at epilepsy surgery show a severe injury response. This response involves both neuronal degeneration and the proliferation of reactive cells. A salient feature of the reactive cells is the co-expression of microglial and astrocytic

  6. Utah optrode array customization using stereotactic brain atlases and 3-D CAD modeling for optogenetic neocortical interrogation in small rodents and nonhuman primates.

    Science.gov (United States)

    Boutte, Ronald W; Merlin, Sam; Yona, Guy; Griffiths, Brandon; Angelucci, Alessandra; Kahn, Itamar; Shoham, Shy; Blair, Steve

    2017-10-01

    As the optogenetic field expands, the need for precise targeting of neocortical circuits only grows more crucial. This work demonstrates a technique for using Solidworks ® computer-aided design (CAD) and readily available stereotactic brain atlases to create a three-dimensional (3-D) model of the dorsal region of area visual cortex 4 (V4D) of the macaque monkey ( Macaca fascicularis ) visual cortex. The 3-D CAD model of the brain was used to customize an [Formula: see text] Utah optrode array (UOA) after it was determined that a high-density ([Formula: see text]) UOA caused extensive damage to marmoset ( Callithrix jacchus ) primary visual cortex as assessed by electrophysiological recording of spiking activity through a 1.5-mm-diameter through glass via. The [Formula: see text] UOA was customized for optrode length ([Formula: see text]), optrode width ([Formula: see text]), optrode pitch ([Formula: see text]), backplane thickness ([Formula: see text]), and overall form factor ([Formula: see text]). Two [Formula: see text] UOAs were inserted into layer VI of macaque V4D cortices with minimal damage as assessed in fixed tissue cytochrome oxidase staining in nonrecoverable surgeries. Additionally, two [Formula: see text] arrays were implanted in mice ( Mus musculus ) motor cortices, providing early evidence for long-term tolerability (over 6 months), and for the ability to integrate the UOA with a Holobundle light delivery system toward patterned optogenetic stimulation of cortical networks.

  7. Study on team characteristics influencing on nuclear safety culture in Korea based on Bayesian networks

    Energy Technology Data Exchange (ETDEWEB)

    Young-gab, K.; Chan-ho, S.; Jeong-jin, P., E-mail: iamkyg@khnp.co.kr, E-mail: chsung@khnp.co.kr, E-mail: jjpark82@khnp.co.kr [Korea Hydro & Nuclear Power Co., Central Research Inst., Yuseong-gu, Daejeon (Korea, Republic of)

    2014-07-01

    The safety culture of Korean nuclear power plants has been settled down as an organizational culture since the Chernobyl accident in 1986. Reason (1997) proposed that safety culture is a sub-culture of corporate culture and sub-culture is a term that can be used interchangeably to a sub-group of people (i.e., department, workgroup). Therefore, the safety culture of organization comprised of various teams can be told as a culture to reflect team characteristics and interact with each other. Team characteristics have something to do with a successful task performance and task efficiency. However, the team characteristics in nuclear power plant have to consider safety preferentially rather than performance. Team characteristics for a safety are necessary to ensure and enhance the safety of safety-critical system. This paper proposed team characteristics for a safety which influence on the strong and vulnerable area of safety culture. These characteristics were analyzed on the basis of the safety culture evaluation which was performed to measure the level of plant workers' safety culture in 2013. The model of team characteristics was constructed considering Bayesian inference and the result was proposed according to workers' awareness. Safety team characteristics have a direct or indirect effect on the safety of nuclear power plants. Therefore, if they are improved and trained continuously, the safety of nuclear power plants might be enhanced. (author)

  8. Study on team characteristics influencing on nuclear safety culture in Korea based on Bayesian networks

    International Nuclear Information System (INIS)

    Young-gab, K.; Chan-ho, S.; Jeong-jin, P.

    2014-01-01

    The safety culture of Korean nuclear power plants has been settled down as an organizational culture since the Chernobyl accident in 1986. Reason (1997) proposed that safety culture is a sub-culture of corporate culture and sub-culture is a term that can be used interchangeably to a sub-group of people (i.e., department, workgroup). Therefore, the safety culture of organization comprised of various teams can be told as a culture to reflect team characteristics and interact with each other. Team characteristics have something to do with a successful task performance and task efficiency. However, the team characteristics in nuclear power plant have to consider safety preferentially rather than performance. Team characteristics for a safety are necessary to ensure and enhance the safety of safety-critical system. This paper proposed team characteristics for a safety which influence on the strong and vulnerable area of safety culture. These characteristics were analyzed on the basis of the safety culture evaluation which was performed to measure the level of plant workers' safety culture in 2013. The model of team characteristics was constructed considering Bayesian inference and the result was proposed according to workers' awareness. Safety team characteristics have a direct or indirect effect on the safety of nuclear power plants. Therefore, if they are improved and trained continuously, the safety of nuclear power plants might be enhanced. (author)

  9. Preparing culture change agents for academic medicine in a multi-institutional consortium: the C - change learning action network.

    Science.gov (United States)

    Pololi, Linda H; Krupat, Edward; Schnell, Eugene R; Kern, David E

    2013-01-01

    Research suggests an ongoing need for change in the culture of academic medicine. This article describes the structure, activities and evaluation of a culture change project: the C - Change Learning Action Network (LAN) and its impact on participants. The LAN was developed to create the experience of a culture that would prepare participants to facilitate a culture in academic medicine that would be more collaborative, inclusive, relational, and that supports the humanity and vitality of faculty. Purposefully diverse faculty, leaders, and deans from 5 US medical schools convened in 2 1/2-day meetings biannually over 4 years. LAN meetings employed experiential, cognitive, and affective learning modes; innovative dialogue strategies; and reflective practice aimed at facilitating deep dialogue, relationship formation, collaboration, authenticity, and transformative learning to help members experience the desired culture. Robust aggregated qualitative and quantitative data collected from the 5 schools were used to inform and stimulate culture-change plans. Quantitative and qualitative evaluation methods were used. Participants indicated that a safe, supportive, inclusive, collaborative culture was established in LAN and highly valued. LAN members reported a deepened understanding of organizational change, new and valued interpersonal connections, increased motivation and resilience, new skills and approaches, increased self-awareness and personal growth, emotional connection to the issues of diversity and inclusion, and application of new learnings in their work. A carefully designed multi-institutional learning community can transform the way participants experience and view institutional culture. It can motivate and prepare them to be change agents in their own institutions. Copyright © 2013 The Alliance for Continuing Education in the Health Professions, the Society for Academic Continuing Medical Education, and the Council on CME, Association for Hospital Medical

  10. Culture, social networks, and information sharing: An exploratory study of Japanese aerospace engineers' information-seeking processes and habits in light of cultural factors

    Science.gov (United States)

    Sato, Yuko

    The purpose of this study was to investigate the effects of culture and language on Japanese aerospace engineers' information-seeking processes by both quantitative and qualitative approaches. The Japanese sample consisted of 162 members of the Japan Society for Aeronautical and Space Sciences (JSASS). U.S. aerospace engineers served as a reference point, consisting of 213 members of the American Institute of Aeronautics and Astronautics (AIAA). The survey method was utilized in gathering data using self-administered mail questionnaires in order to explore the following eight areas: (1) the content and use of information resources; (2) production and use of information products; (3) methods of accessing information service providers; (4) foreign language skills; (5) studying/researching/collaborating abroad as a tool in expanding information resources; (6) scientific and technical societies as networking tools; (7) alumni associations (school/class reunions) as networking tools; and (8) social, corporate, civic and health/fitness clubs as networking tools. Nine Japanese cultural factors expressed as statements about Japanese society are as follows: (1) information is neither autonomous, objective, nor independent of the subject of cognition; (2) information and knowledge are not readily accessible to the public; (3) emphasis on groups is reinforced in a hierarchical society; (4) social networks thrive as information-sharing vehicles; (5) high context is a predominant form of communication in which most of the information is already in the person, while very little is in the coded, transmitted part of the message; (6) obligations based on mutual trust dictate social behaviors instead of contractual agreements; (7) a surface message is what is presented while a bottom-line message is true feeling privately held; (8) various religious beliefs uphold a work ethic based on harmony; (9) ideas from outside are readily assimilated into its own society. The result of the

  11. Predictive values of F-18-FDG PET and ictal SPECT to find epileptogenic zones in cryptogenic neocortical epilepsies

    International Nuclear Information System (INIS)

    Lee, D. S.; Lee, S. K.; Jeong, Z. K.; Kim, H. Z.; Lee, M. C.; Ko, C. S.

    1997-01-01

    Though cumulated reported sensitivity were 33% (F-18-FDG PET) and 81%(ictal SPECT) in neocortical epilepsy, positive predictive values rather than sensitivity should be referred if we wish to know the reliability of positive findings to predict epileptogenic zones. In cryptogenic neocortical epilepsy which did not have structural lesions on MR, we tried to find performance of F-18-FDG PET and ictal SPECT to find epileptogenic zones. In 77 patients who had no lesion on MR and who were suspected to have neocortical epilepsy on video monitored EEG, ictal SPECT were done in 44 patients and F-18-FDG PET were done in 70 patients. Invasive study and operation was done in 24 patients. The most hyper perfused area or prominently hypometabolic area was suspected to be epileptogenic on ictal SPECT or F-18-FDG PET, respectively. We could find zones of ictal hyperperfusion in 34/44(78%) patients. Positive predictive values of ictal hyperperfusion were 58%, 60%, and 12.5% in frontal lobes (n=12), lateral temporal lobes (20), and parietal lobes (8). We could find hypometabolic areas in 50/70(76%) patients. Positive predictive values of hypometabolism were 78%, 71%, 33%, and 25% in frontal lobes (9), lateral temporal lobes (28), parietal lobes (3) and occipital lobes (4). Among 24 patients who were operated, 17 patients were followed up more than 7 months (15 ± 5). Thirteen patients improved (10 : Engel class I or II, 2: 90% reduction, 1: 75% reduction but multifocal). Five among 11 PET studies were correct, 3 among 10 SPECT studies, and 6 among 11 PET/SPECT studies (55%) were correct for localization. In conclusion, three fourths of patients gave positive results to localized epileptogenic zones in cryptogenic neocortical epilepsy, and predictive values of ictal hyperperfusion or interictal hypometabolism were highest in frontal or lateral temporal lobes if these lobes were found to be culprit though rapid ictal propagation of cortical hyperperfusion confounded the exact

  12. The HIV-1 viral protein Tat increases glutamate and decreases GABA exocytosis from human and mouse neocortical nerve endings.

    Science.gov (United States)

    Musante, Veronica; Summa, Maria; Neri, Elisa; Puliti, Aldamaria; Godowicz, Tomasz T; Severi, Paolo; Battaglia, Giuseppe; Raiteri, Maurizio; Pittaluga, Anna

    2010-08-01

    Human immunodeficiency virus-1 (HIV-1)-encoded transactivator of transcription (Tat) potentiated the depolarization-evoked exocytosis of [(3)H]D-aspartate ([(3)H]D-ASP) from human neocortical terminals. The metabotropic glutamate (mGlu) 1 receptor antagonist 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester (CPCCOEt) prevented this effect, whereas the mGlu5 receptor antagonist 2-methyl-6-(phenylethynyl) pyridine hydrochloride (MPEP) was ineffective. Western blot analysis showed that human neocortex synaptosomes possess mGlu1 and mGlu5 receptors. Tat potentiated the K(+)-evoked release of [(3)H]D-ASP or of endogenous glutamate from mouse neocortical synaptosomes in a CPCCOEt-sensitive and MPEP-insensitive manner. Deletion of mGlu1 receptors (crv4/crv4 mice) or mGlu5 receptors (mGlu5(-/-)mouse) silenced Tat effects. Tat enhanced inositol 1,4,5-trisphosphate production in human and mouse neocortical synaptosomes, consistent with the involvement of group I mGlu receptors. Tat inhibited the K(+)-evoked release of [(3)H]gamma-aminobutyric acid ([(3)H]GABA) from human synaptosomes and that of endogenous GABA or [(3)H]GABA from mouse nerve terminals; the inhibition was insensitive to CPCCOEt or MPEP. Tat-induced effects were retained by Tat(37-72) but not by Tat(48-85). In mouse neocortical slices, Tat facilitated the K(+)- and the veratridine-induced release of [(3)H]D-ASP in a CPCCOEt-sensitive manner and was ineffective in crv4/crv4 mouse slices. These observations are relevant to the comprehension of the pathophysiological effects of Tat in central nervous system and may suggest new potential therapeutic approaches to the cure of HIV-1-associated dementia.

  13. Conical expansion of the outer subventricular zone and the role of neocortical folding in evolution and development

    Directory of Open Access Journals (Sweden)

    Eric eLewitus

    2013-08-01

    Full Text Available There is a basic rule to mammalian neocortical expansion: as it expands, so does it fold. The degree to which it folds, however, cannot strictly be attributed to its expansion. Across species, cortical volume does not keep pace with cortical surface area, but rather folds appear more rapidly than expected. As a result, larger brains quickly become disproportionately more convoluted than smaller brains. Both the absence (lissencephaly and presence (gyrencephaly of cortical folds is observed in all mammalian orders and, while there is likely some phylogenetic signature to the evolutionary appearance of gyri and sulci, there are undoubtedly universal trends to the acquisition of folds in an expanding neocortex. Whether these trends are governed by conical expansion of neocortical germinal zones, the distribution of cortical connectivity, or a combination of growth- and connectivity-driven forces remains an open question. But the importance of cortical folding for evolution of the uniquely mammalian neocortex, as well as for the incidence of neuropathologies in humans, is undisputed. In this hypothesis and theory article, we will summarize the development of cortical folds in the neocortex, consider the relative influence of growth- versus connectivity-driven forces for the acquisition of cortical folds between and within species, assess the genetic, cell-biological, and mechanistic implications for neocortical expansion, and discuss the significance of these implications for human evolution, development, and disease. We will argue that evolutionary increases in the density of neuron production, achieved via maintenance of a basal proliferative niche in the neocortical germinal zones, drive the conical migration of neurons towards the cortical surface and ultimately lead to the establishment of cortical folds in large-brained mammal species.

  14. Uptake and metabolism of fructose by rat neocortical cells in vivo and by isolated nerve terminals in vitro.

    Science.gov (United States)

    Hassel, Bjørnar; Elsais, Ahmed; Frøland, Anne-Sofie; Taubøll, Erik; Gjerstad, Leif; Quan, Yi; Dingledine, Raymond; Rise, Frode

    2015-05-01

    Fructose reacts spontaneously with proteins in the brain to form advanced glycation end products (AGE) that may elicit neuroinflammation and cause brain pathology, including Alzheimer's disease. We investigated whether fructose is eliminated by oxidative metabolism in neocortex. Injection of [(14) C]fructose or its AGE-prone metabolite [(14) C]glyceraldehyde into rat neocortex in vivo led to formation of (14) C-labeled alanine, glutamate, aspartate, GABA, and glutamine. In isolated neocortical nerve terminals, [(14) C]fructose-labeled glutamate, GABA, and aspartate, indicating uptake of fructose into nerve terminals and oxidative fructose metabolism in these structures. This was supported by high expression of hexokinase 1, which channels fructose into glycolysis, and whose activity was similar with fructose or glucose as substrates. By contrast, the fructose-specific ketohexokinase was weakly expressed. The fructose transporter Glut5 was expressed at only 4% of the level of neuronal glucose transporter Glut3, suggesting transport across plasma membranes of brain cells as the limiting factor in removal of extracellular fructose. The genes encoding aldose reductase and sorbitol dehydrogenase, enzymes of the polyol pathway that forms glucose from fructose, were expressed in rat neocortex. These results point to fructose being transported into neocortical cells, including nerve terminals, and that it is metabolized and thereby detoxified primarily through hexokinase activity. We asked how the brain handles fructose, which may react spontaneously with proteins to form 'advanced glycation end products' and trigger inflammation. Neocortical cells took up and metabolized extracellular fructose oxidatively in vivo, and isolated nerve terminals did so in vitro. The low expression of fructose transporter Glut5 limited uptake of extracellular fructose. Hexokinase was a main pathway for fructose metabolism, but ketohexokinase (which leads to glyceraldehyde formation) was

  15. cultural

    Directory of Open Access Journals (Sweden)

    Irene Kreutz

    2006-01-01

    Full Text Available Es un estudio cualitativo que adoptó como referencial teorico-motodológico la antropología y la etnografía. Presenta las experiencias vivenciadas por mujeres de una comunidad en el proceso salud-enfermedad, con el objetivo de comprender los determinantes sócio-culturales e históricos de las prácticas de prevención y tratamiento adoptados por el grupo cultural por medio de la entrevista semi-estructurada. Los temas que emergieron fueron: la relación entre la alimentación y lo proceso salud-enfermedad, las relaciones con el sistema de salud oficial y el proceso salud-enfermedad y lo sobrenatural. Los dados revelaron que los moradores de la comunidad investigada tienen un modo particular de explicar sus procedimientos terapéuticos. Consideramos que es papel de los profesionales de la salud en sus prácticas, la adopción de abordajes o enfoques que consideren al individuo en su dimensión sócio-cultural e histórica, considerando la enorme diversidad cultural en nuestro país.

  16. Large-scale, high-resolution multielectrode-array recording depicts functional network differences of cortical and hippocampal cultures.

    Directory of Open Access Journals (Sweden)

    Shinya Ito

    Full Text Available Understanding the detailed circuitry of functioning neuronal networks is one of the major goals of neuroscience. Recent improvements in neuronal recording techniques have made it possible to record the spiking activity from hundreds of neurons simultaneously with sub-millisecond temporal resolution. Here we used a 512-channel multielectrode array system to record the activity from hundreds of neurons in organotypic cultures of cortico-hippocampal brain slices from mice. To probe the network structure, we employed a wavelet transform of the cross-correlogram to categorize the functional connectivity in different frequency ranges. With this method we directly compare, for the first time, in any preparation, the neuronal network structures of cortex and hippocampus, on the scale of hundreds of neurons, with sub-millisecond time resolution. Among the three frequency ranges that we investigated, the lower two frequency ranges (gamma (30-80 Hz and beta (12-30 Hz range showed similar network structure between cortex and hippocampus, but there were many significant differences between these structures in the high frequency range (100-1000 Hz. The high frequency networks in cortex showed short tailed degree-distributions, shorter decay length of connectivity density, smaller clustering coefficients, and positive assortativity. Our results suggest that our method can characterize frequency dependent differences of network architecture from different brain regions. Crucially, because these differences between brain regions require millisecond temporal scales to be observed and characterized, these results underscore the importance of high temporal resolution recordings for the understanding of functional networks in neuronal systems.

  17. Productive Tensions in a Cross-Cultural Peer Mentoring Women's Network: A Social Capital Perspective

    Science.gov (United States)

    Esnard, Talia; Cobb-Roberts, Deirdre; Agosto, Vonzell; Karanxha, Zorka; Beck, Makini; Wu, Ke; Unterreiner, Ann

    2015-01-01

    A growing body of researchers documents the unique barriers women face in their academic career progression and the significance of mentoring networks for advancement of their academic trajectories as faculty. However, few researchers explore the embedded tensions and conflicts in the social processes and relations of mentoring networks, and the…

  18. Visual social network analysis: effective approach to model complex human social, behaviour & culture.

    Science.gov (United States)

    Ahram, Tareq Z; Karwowski, Waldemar

    2012-01-01

    The advent and adoption of internet-based social networking has significantly altered our daily lives. The educational community has taken notice of the positive aspects of social networking such as creation of blogs and to support groups of system designers going through the same challenges and difficulties. This paper introduces a social networking framework for collaborative education, design and modeling of the next generation of smarter products and services. Human behaviour modeling in social networking application aims to ensure that human considerations for learners and designers have a prominent place in the integrated design and development of sustainable, smarter products throughout the total system lifecycle. Social networks blend self-directed learning and prescribed, existing information. The self-directed element creates interest within a learner and the ability to access existing information facilitates its transfer, and eventual retention of knowledge acquired.

  19. The Spirit in the Network: Models for Spirituality in a Technological Culture.

    NARCIS (Netherlands)

    Coeckelbergh, Mark

    2010-01-01

    Can a technological culture accommodate spiritual experience and spiritual thinking? If so, what kind of spirituality? I explore the relation between technology and spirituality by constructing and discussing several models for spirituality in a technological culture. I show that although gnostic

  20. Impedance Spectroscopic Characterisation of Porosity in 3D Cell Culture Scaffolds with Different Channel Networks

    DEFF Research Database (Denmark)

    Canali, Chiara; Mohanty, Soumyaranjan; Heiskanen, Arto

    2015-01-01

    We present the application of electrochemical impedance spectroscopy (EIS) as a method for discriminating between different polydimethylsiloxane (PDMS) scaffolds for three-dimensional (3D) cell cultures. The validity of EIS characterisation for scaffolds having different degree of porosity...... serve as means of single-frequency measurements for fast scaffold characterization combined with in vitro monitoring of 3D cell cultures....

  1. Immune Regulator MCPIP1 Modulates TET Expression during Early Neocortical Development

    Directory of Open Access Journals (Sweden)

    Huihui Jiang

    2016-09-01

    Full Text Available MCPIP1 is a recently identified immune regulator that plays critical roles in preventing immune disorders, and is also present in the brain. Currently an unresolved question remains as to how MCPIP1 performs its non-immune functions in normal brain development. Here, we report that MCPIP1 is abundant in neural progenitor cells (NPCs and newborn neurons during the early stages of neurogenesis. The suppression of MCPIP1 expression impairs normal neuronal differentiation, cell-cycle exit, and concomitant NPC proliferation. MCPIP1 is important for maintenance of the NPC pool. Notably, we demonstrate that MCPIP1 reduces TET (TET1/TET2/TET3 levels and then decreases 5-hydroxymethylcytosine levels. Furthermore, the MCPIP1 interaction with TETs is involved in neurogenesis and in establishing the proper number of NPCs in vivo. Collectively, our findings not only demonstrate that MCPIP1 plays an important role in early cortical neurogenesis but also reveal an unexpected link between neocortical development, immune regulators, and epigenetic modification.

  2. Medial temporal and neocortical contributions to remote memory for semantic narratives: evidence from amnesia.

    Science.gov (United States)

    Verfaellie, Mieke; Bousquet, Kathryn; Keane, Margaret M

    2014-08-01

    Studies of remote memory for semantic facts and concepts suggest that hippocampal lesions lead to a temporally graded impairment that extends no more than ten years prior to the onset of amnesia. Such findings have led to the notion that once consolidated, semantic memories are represented neocortically and are no longer dependent on the hippocampus. Here, we examined the fate of well-established semantic narratives following medial temporal lobe (MTL) lesions. Seven amnesic patients, five with lesions restricted to the MTL and two with lesions extending into lateral temporal cortex (MTL+), were asked to recount fairy tales and bible stories that they rated as familiar. Narratives were scored for number and type of details, number of main thematic elements, and order in which the main thematic elements were recounted. In comparison to controls, patients with MTL lesions produced fewer details, but the number and order of main thematic elements generated was intact. By contrast, patients with MTL+ lesions showed a pervasive impairment, affecting not only the generation of details, but also the generation and ordering of main steps. These findings challenge the notion that, once consolidated, semantic memories are no longer dependent on the hippocampus for retrieval. Possible hippocampal contributions to the retrieval of detailed semantic narratives are discussed. Published by Elsevier Ltd.

  3. Neocortical dynamics at multiple scales: EEG standing waves, statistical mechanics, and physical analogs.

    Science.gov (United States)

    Ingber, Lester; Nunez, Paul L

    2011-02-01

    The dynamic behavior of scalp potentials (EEG) is apparently due to some combination of global and local processes with important top-down and bottom-up interactions across spatial scales. In treating global mechanisms, we stress the importance of myelinated axon propagation delays and periodic boundary conditions in the cortical-white matter system, which is topologically close to a spherical shell. By contrast, the proposed local mechanisms are multiscale interactions between cortical columns via short-ranged non-myelinated fibers. A mechanical model consisting of a stretched string with attached nonlinear springs demonstrates the general idea. The string produces standing waves analogous to large-scale coherent EEG observed in some brain states. The attached springs are analogous to the smaller (mesoscopic) scale columnar dynamics. Generally, we expect string displacement and EEG at all scales to result from both global and local phenomena. A statistical mechanics of neocortical interactions (SMNI) calculates oscillatory behavior consistent with typical EEG, within columns, between neighboring columns via short-ranged non-myelinated fibers, across cortical regions via myelinated fibers, and also derives a string equation consistent with the global EEG model. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. POMT1-associated walker-warburg syndrome: a disorder of dendritic development of neocortical neurons.

    Science.gov (United States)

    Judas, M; Sedmak, G; Rados, M; Sarnavka, V; Fumić, K; Willer, T; Gross, C; Hehr, U; Strahl, S; Cuk, M; Barić, I

    2009-02-01

    We have analyzed the morphology and dendritic development of neocortical neurons in a 2.5-month-old infant with Walker-Warburg syndrome homozygotic for a novel POMT1 gene mutation, by Golgi methods. We found that pyramidal neurons frequently displayed abnormal (oblique, horizontal, or inverted) orientation. A novel finding of this study is that members of the same population of pyramidal neurons display different stages of development of their dendritic arborizations: some neurons had poorly developed dendrites and thus resembled pyramidal neurons of the late fetal cortex; for some neurons, the level of differentiation corresponded to that in the newborn cortex; finally, some neurons had quite elaborate dendritic trees as expected for the cortex of 2.5-month-old infant. In addition, apical dendrites of many pyramidal neurons were conspiciously bent to one side, irrespective to the general orientation of the pyramidal neuron. These findings suggest that Walker-Warburg lissencephaly is characterized by two hitherto unnoticed pathogenetic changes in the cerebral cortex: (a) heterochronic decoupling of dendritic maturation within the same neuronal population (with some members significantly lagging behind the normal maturational schedule) and (b) anisotropically distorted shaping of dendritic trees, probably caused by patchy displacement of molecular guidance cues for dendrites in the malformed cortex. Copyright Georg Thieme Verlag KG Stuttgart New York.

  5. Using Cultural Historical Activity Theory (CHAT) to Frame `SuperclubsPLUS', an Online Social Network for Children

    Science.gov (United States)

    Masters, Jennifer

    This paper uses a Cultural Historical Activity Theory framework to describe a social-networking online community project, “SuperclubsPLUS”, for children aged 6-12. The use of the CHAT frame enables a detailed description of connections within the project as participants work together to achieve individual and common goals. Application of this structure to the SuperclubsPLUS environment supports the concept that the community is continually changing, shaped by the interactions of the participants. It is anticipated that this snapshot of the project will provide a tangible base in order to further develop and map ongoing patterns of interaction for research.

  6. The U.S. Culture Collection Network Responding to the Requirements of the Nagoya Protocol on Access and Benefit Sharing

    Directory of Open Access Journals (Sweden)

    Kevin McCluskey

    2017-08-01

    Full Text Available The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity (CBD. The meeting included representatives of many culture collections and other biological collections, the U.S. Department of State, U.S. Department of Agriculture, Secretariat of the CBD, interested scientific societies, and collection groups, including Scientific Collections International and the Global Genome Biodiversity Network. The participants learned about the policies of the United States and other countries regarding access to genetic resources, the definition of genetic resources, and the status of historical materials and genetic sequence information. Key topics included what constitutes access and how the CBD Access and Benefit-Sharing Clearing-House can help guide researchers through the process of obtaining Prior Informed Consent on Mutually Agreed Terms. U.S. scientists and their international collaborators are required to follow the regulations of other countries when working with microbes originally isolated outside the United States, and the local regulations required by the Nagoya Protocol vary by the country of origin of the genetic resource. Managers of diverse living collections in the United States described their holdings and their efforts to provide access to genetic resources. This meeting laid the foundation for cooperation in establishing a set of standard operating procedures for U.S. and international culture collections in response to the Nagoya Protocol.

  7. Effect of correlating adjacent neurons for identifying communications: Feasibility experiment in a cultured neuronal network

    OpenAIRE

    Yoshi Nishitani; Chie Hosokawa; Yuko Mizuno-Matsumoto; Tomomitsu Miyoshi; Shinichi Tamura

    2017-01-01

    Neuronal networks have fluctuating characteristics, unlike the stable characteristics seen in computers. The underlying mechanisms that drive reliable communication among neuronal networks and their ability to perform intelligible tasks remain unknown. Recently, in an attempt to resolve this issue, we showed that stimulated neurons communicate via spikes that propagate temporally, in the form of spike trains. We named this phenomenon “spike wave propagation”. In these previous studies, using ...

  8. Changing the culture of academic medicine: the C-Change learning action network and its impact at participating medical schools.

    Science.gov (United States)

    Krupat, Edward; Pololi, Linda; Schnell, Eugene R; Kern, David E

    2013-09-01

    The culture of academic medicine has been described as hierarchical, competitive, and not highly supportive of female or minority faculty. In response to this, the authors designed the Learning Action Network (LAN), which was part of the National Initiative on Gender, Culture and Leadership in Medicine (C-Change). The LAN is a five-school consortium aimed at changing the organizational culture of its constituent institutions. The authors selected LAN schools to be geographically diverse and representative of U.S. medical schools. Institutional leaders and faculty representatives from constituent schools met twice yearly for four years (2006-2010), forming a cross-institutional learning community. Through their quarterly listing of institutional activities, schools reported a wide array of actions. Most common were increased faculty development and/or mentoring, new approaches to communication, and adoption of new policies and procedures. Other categories included data collection/management, engagement of key stakeholders, education regarding gender/diversity, and new/expanded leadership positions. Through exit interviews, most participants reported feeling optimistic about maintaining the momentum of change. However, some, especially in schools with leadership changes, expressed uncertainty. Participants reported that they felt that the LAN enabled, empowered, facilitated, and/or caused the reported actions.For others who might want to work toward changing the culture of academic medicine, the authors offer several lessons learned from their experiences with C-Change. Most notably, people, structures, policies, and reward systems must be put into place to support cultural values, and broad-based support should be created in order for changes to persist when inevitable transitions in leadership occur.

  9. Distribution and function of HCN channels in the apical dendritic tuft of neocortical pyramidal neurons.

    Science.gov (United States)

    Harnett, Mark T; Magee, Jeffrey C; Williams, Stephen R

    2015-01-21

    The apical tuft is the most remote area of the dendritic tree of neocortical pyramidal neurons. Despite its distal location, the apical dendritic tuft of layer 5 pyramidal neurons receives substantial excitatory synaptic drive and actively processes corticocortical input during behavior. The properties of the voltage-activated ion channels that regulate synaptic integration in tuft dendrites have, however, not been thoroughly investigated. Here, we use electrophysiological and optical approaches to examine the subcellular distribution and function of hyperpolarization-activated cyclic nucleotide-gated nonselective cation (HCN) channels in rat layer 5B pyramidal neurons. Outside-out patch recordings demonstrated that the amplitude and properties of ensemble HCN channel activity were uniform in patches excised from distal apical dendritic trunk and tuft sites. Simultaneous apical dendritic tuft and trunk whole-cell current-clamp recordings revealed that the pharmacological blockade of HCN channels decreased voltage compartmentalization and enhanced the generation and spread of apical dendritic tuft and trunk regenerative activity. Furthermore, multisite two-photon glutamate uncaging demonstrated that HCN channels control the amplitude and duration of synaptically evoked regenerative activity in the distal apical dendritic tuft. In contrast, at proximal apical dendritic trunk and somatic recording sites, the blockade of HCN channels decreased excitability. Dynamic-clamp experiments revealed that these compartment-specific actions of HCN channels were heavily influenced by the local and distributed impact of the high density of HCN channels in the distal apical dendritic arbor. The properties and subcellular distribution pattern of HCN channels are therefore tuned to regulate the interaction between integration compartments in layer 5B pyramidal neurons. Copyright © 2015 the authors 0270-6474/15/351024-14$15.00/0.

  10. [Pathological neocortical findings in patients with medication-resistant medial temporal lobe epilepsy submitted to surgery].

    Science.gov (United States)

    Estupiñán-Díaz, B; Morales-Chacón, L M; Lorigados-Pedre, L; García-Maeso, I; Bender-del Busto, J E; Trápaga-Quincoses, O; Hidalgo-Portal, L; García-Navarro, M E; Sánchez-Coroneaux, A; Orozco-Suárez, S

    The dual pathology consisting of hippocampal sclerosis plus focal cortical dysplasia (FCD) is often reported in patients with medication-resistant medial temporal lobe epilepsy (MTLE). To determine the histopathological changes that take place in the neocortex of patients with medication-resistant MTLE submitted to surgery and to evaluate the relation between the histopathological changes, pathological background and the clinical course of patients who had received surgical treatment. Tissue obtained by en bloc resection from the neocortex of 18 patients with MTLE refractory to medical treatment was processed histologically and a tailored temporal lobectomy was performed with electrocorticography. Dual pathology was diagnosed in 13 patients (72.2%). Imaging studies confirmed the existence of mesial sclerosis of the temporal in 100% of cases and there was no evidence of neocortical lesions. Histologically, 46.15% and 38.46% of the patients were diagnosed as belonging to FCD type 1a and FCD type 1b, respectively. Only one patient presented FCD type 2a. A statistically significant relation was found between the presence of dual pathology and the existence of an early precipitating injury (p = 0.04). One year after surgery, 72.7% (8/11) patients with dual pathology were classified as belonging to Engel class I. In patients with MTLE there are microscopic FCD-type alterations in the neocortex. There is an association between these alterations and the existence of an initial precipitating injury. Complete resection of the epileptogenic area, which is guaranteed by the lobectomy tailored by electrocorticography, allows patients to enjoy a favourable post-surgical progression one year after surgery.

  11. [A surgical case of mesial temporal lobe epilepsy associated with hippocampal sclerosis and traumatic neocortical lesion].

    Science.gov (United States)

    Kitazawa, Yu; Jin, Kazutaka; Iwasaki, Masaki; Suzuki, Hiroyoshi; Tanaka, Fumiaki; Nakasato, Nobukazu

    2017-11-25

    A 26-year-old right-handed woman, with a history of left temporal lobe contusion caused by a fall at the age of 9 months, started to have complex partial seizures with oral automatism at the age of 7 years. The seizures occurred once or twice a month despite combination therapy with several antiepileptic agents. Her history and imaging studies suggested the diagnosis of epilepsy arising from traumatic neocortical temporal lesion. Comprehensive assessment including long-term video EEG monitoring, MRI, FDG-PET, MEG, and neuropsychological evaluation was performed at the age of 26 years. The diagnosis was left mesial temporal lobe epilepsy associated with hippocampal atrophy and traumatic temporal cortical lesion. The patient was readmitted for surgical treatment at the age of 27 years. Intracranial EEG monitoring showed that ictal discharges started in the left hippocampus and spread to the traumatic lesion in the left posterior superior temporal gyrus 10 seconds after the onset. This case could not be classified as dual pathology exactly, because the traumatic left temporal cortical lesion did not show independent epileptogenicity. However, the traumatic lesion was highly likely to be the source of the epileptogenicity, and she had right hemispheric dominance for language and functional deterioration in the whole temporal cortex. Therefore, left amygdalo-hippocampectomy and left temporal lobectomy including the traumatic lesion were performed according to the diagnosis of dual pathology. Subsequently, she remained seizure-free for 3 years. Comprehensive assessment of seizure semiology, neurophysiology, neuroradiology, and neuropsychology is important to determine the optimum therapeutic strategies for drug-resistant epilepsy.

  12. Neocortical neuron types in Xenarthra and Afrotheria: implications for brain evolution in mammals.

    Science.gov (United States)

    Sherwood, Chet C; Stimpson, Cheryl D; Butti, Camilla; Bonar, Christopher J; Newton, Alisa L; Allman, John M; Hof, Patrick R

    2009-02-01

    Interpreting the evolution of neuronal types in the cerebral cortex of mammals requires information from a diversity of species. However, there is currently a paucity of data from the Xenarthra and Afrotheria, two major phylogenetic groups that diverged close to the base of the eutherian mammal adaptive radiation. In this study, we used immunohistochemistry to examine the distribution and morphology of neocortical neurons stained for nonphosphorylated neurofilament protein, calbindin, calretinin, parvalbumin, and neuropeptide Y in three xenarthran species-the giant anteater (Myrmecophaga tridactyla), the lesser anteater (Tamandua tetradactyla), and the two-toed sloth (Choloepus didactylus)-and two afrotherian species-the rock hyrax (Procavia capensis) and the black and rufous giant elephant shrew (Rhynchocyon petersi). We also studied the distribution and morphology of astrocytes using glial fibrillary acidic protein as a marker. In all of these species, nonphosphorylated neurofilament protein-immunoreactive neurons predominated in layer V. These neurons exhibited diverse morphologies with regional variation. Specifically, high proportions of atypical neurofilament-enriched neuron classes were observed, including extraverted neurons, inverted pyramidal neurons, fusiform neurons, and other multipolar types. In addition, many projection neurons in layers II-III were found to contain calbindin. Among interneurons, parvalbumin- and calbindin-expressing cells were generally denser compared to calretinin-immunoreactive cells. We traced the evolution of certain cortical architectural traits using phylogenetic analysis. Based on our reconstruction of character evolution, we found that the living xenarthrans and afrotherians show many similarities to the stem eutherian mammal, whereas other eutherian lineages display a greater number of derived traits.

  13. Electroconvulsive therapy and structural neuroplasticity in neocortical, limbic and paralimbic cortex

    Science.gov (United States)

    Pirnia, T; Joshi, S H; Leaver, A M; Vasavada, M; Njau, S; Woods, R P; Espinoza, R; Narr, K L

    2016-01-01

    Electroconvulsive therapy (ECT) is a highly effective and rapidly acting treatment for severe depression. To understand the biological bases of therapeutic response, we examined variations in cortical thickness from magnetic resonance imaging (MRI) data in 29 patients scanned at three time points during an ECT treatment index series and in 29 controls at two time points. Changes in thickness across time and with symptom improvement were evaluated at high spatial resolution across the cortex and within discrete cortical regions of interest. Patients showed increased thickness over the course of ECT in the bilateral anterior cingulate cortex (ACC), inferior and superior temporal, parahippocampal, entorhinal and fusiform cortex and in distributed prefrontal areas. No changes across time occurred in controls. In temporal and fusiform regions showing significant ECT effects, thickness differed between patients and controls at baseline and change in thickness related to therapeutic response in patients. In the ACC, these relationships occurred in treatment responders only, and thickness measured soon after treatment initiation predicted the overall ECT response. ECT leads to widespread neuroplasticity in neocortical, limbic and paralimbic regions and changes relate to the extent of antidepressant response. Variations in ACC thickness, which discriminate treatment responders and predict response early in the course of ECT, may represent a biomarker of overall clinical outcome. Because post-mortem studies show focal reductions in glial density and neuronal size in patients with severe depression, ECT-related increases in thickness may be attributable to neuroplastic processes affecting the size and/or density of neurons and glia and their connections. PMID:27271858

  14. beta1 integrin maintains integrity of the embryonic neocortical stem cell niche.

    Directory of Open Access Journals (Sweden)

    Karine Loulier

    2009-08-01

    to the ventricular surface and maintaining the physical integrity of the neocortical niche, with even transient perturbations resulting in long-lasting cortical defects.

  15. Opening up the solar box: Cultural resource management and actor network theory in solar energy projects in the Mojave Desert

    Science.gov (United States)

    Gorrie, Bryan F.

    This project considers the ways that Actor-Network Theory (ANT) can be brought to bear upon Cultural Resource Management (CRM) practices on renewable energy projects. ANT is a way of making inquiry into scientific knowledge practices and as CRM is intended to preserve environmental, historic, and prehistoric resources, it necessarily involves certain kinds of knowledge generation about regions in which projects are being developed. Because the practice of CRM is complex, involving a range of actors from developers to biologists, native peoples to academics, private landholders to environmental and cultural activists, it is imperative to account for the interests of all stakeholders and to resist devolving into the polemical relations of winners and losers, good and bad participants, or simple situations of right and wrong. This project intends to account for the "matters of concern" of various actors, both primary and secondary, by examining the case study of a single solar installation project in the Mojave Desert. A theoretical description of ANT is provided at the beginning and the concerns of this theory are brought to bear upon the case study project through describing the project, discussing the laws governing CRM on federal lands and in the state of California, and providing the points of view of various interviewees who worked directly or indirectly on various aspects of CRM for the solar project. The creators of ANT claim that it is not a methodology but it does speak to ethnomethodologies in that it insists that there is always something more to learn from inquiring into and describing any given situation. These descriptions avoid generalizations, providing instead various points of entry, from diverse perspectives to the project. There is an invitation to avoid assuming that one knows all there is to know about a given situation and to choose instead to continue investigating and thus give voice to the more obscure, often marginalized, voices in the

  16. Culture, Role and Group Work: A Social Network Analysis Perspective on an Online Collaborative Course

    Science.gov (United States)

    Stepanyan, Karen; Mather, Richard; Dalrymple, Roger

    2014-01-01

    This paper discusses the patterns of network dynamics within a multicultural online collaborative learning environment. It analyses the interaction of participants (both students and facilitators) within a discussion board that was established as part of a 3-month online collaborative course. The study employs longitudinal probabilistic social…

  17. A Cross-cultural Qualitative Examination of Social-networking Sites and Academic Performance

    NARCIS (Netherlands)

    Ozer, Ipek; Karpinski, Aryn; Kirschner, Paul A.

    2018-01-01

    Social-networking site (SNS) use, specifically Facebook®, has remained a controversial subject for many educators and media. Recent studies discuss the negative and positive impacts of SNSs on students’ academic performance. This qualitative study examines the impact of SNSs on students’ academic

  18. Synaptic potentiation facilitates memory-like attractor dynamics in cultured in vitro hippocampal networks.

    Directory of Open Access Journals (Sweden)

    Mark Niedringhaus

    Full Text Available Collective rhythmic dynamics from neurons is vital for cognitive functions such as memory formation but how neurons self-organize to produce such activity is not well understood. Attractor-based computational models have been successfully implemented as a theoretical framework for memory storage in networks of neurons. Additionally, activity-dependent modification of synaptic transmission is thought to be the physiological basis of learning and memory. The goal of this study is to demonstrate that using a pharmacological treatment that has been shown to increase synaptic strength within in vitro networks of hippocampal neurons follows the dynamical postulates theorized by attractor models. We use a grid of extracellular electrodes to study changes in network activity after this perturbation and show that there is a persistent increase in overall spiking and bursting activity after treatment. This increase in activity appears to recruit more "errant" spikes into bursts. Phase plots indicate a conserved activity pattern suggesting that a synaptic potentiation perturbation to the attractor leaves it unchanged. Lastly, we construct a computational model to demonstrate that these synaptic perturbations can account for the dynamical changes seen within the network.

  19. Conserving agrobiodiversity amid global change, migration, and nontraditional livelihood networks: the dynamic uses of cultural landscape knowledge

    Directory of Open Access Journals (Sweden)

    Karl S. Zimmerer

    2014-06-01

    agrobiodiversity between 2006 and 2012 is shown to have occurred amid a transition toward the integral roles of multiple migration-related groups, namely women farmers, consumers, and local business owners; migrants; field caretakers; and local in-migrant laborers. The nontraditional social networks among these livelihood groups must be incorporated into analysis and planning of the design, participation, and monitoring of management and policy options for cultural landscapes ensuring the use, in situ conservation, and sustainability, including ecosystem services, of food plant landraces in global agrobiodiversity hot spots.

  20. Socio-cultural valuation of ecosystem services in a transhumance social-ecological network

    DEFF Research Database (Denmark)

    Oteros-Rozas, E.; Martín-López, B.; González, J.A.

    2014-01-01

    the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services...

  1. Traditional music and the anatomy of the festival network between Yugoslavian cultural politics and vernacular values

    Directory of Open Access Journals (Sweden)

    Jakovljević Rastko

    2012-01-01

    Full Text Available As official policies in the post-war Yugoslavia were oriented towards economy, mainly tied to towns, rural areas were focused on agriculture to a large extent, as it had been before. However, the Party was determined to revive villages, being of the opinion that life in those areas should be purified from “primitivism” so that it could be set to a higher level concerning issues of education, political structure, local organization and cultural life. Since people in villages felt determined to maintain their local culture, customs and music, the State officials had to find ways to articulate uncanny social behaviors. At the time, folklore and vernacular creative impulse in Serbia was sustained as a “hard cultural form” that by accident or on purpose converted into “soft cultural form” through a wide range of festival activities in Yugoslavia. This significant turn permitted “relatively easy separation of embodied performance from meaning and value, and relatively successful transformation at each level” (Appadurai 1996: 90. The discussion of this paper intends to form a dialogue on the transformation of social structure and politics, which gradually led to severe changes in the areas of traditional musical practice.

  2. Statistical mechanics of neocortical interactions: Stability and duration of the 7±2 rule of short-term-memory capacity

    Science.gov (United States)

    Ingber, Lester

    1985-02-01

    This paper is an essential addendum to a previous paper [L. Ingber, Phys. Rev. A 29, 3346 (1984)]. Calculations are presented here to support the claim made in the previous paper that there exists an approximate one-dimensional solution to the two-dimensional neocortical Fokker-Planck equation. This solution is extremely useful, not only for obtaining a closed algebraic expression for the time of first passage, but also for establishing that minima of the associated path-integral stationary Lagrangian are indeed stable points of the transient dynamic system. Also, a relatively nontechnical summary is given of the basic theory.

  3. Estimation of network structure for signal propagations by the analysis of multichannel action potentials in cultured neural networks; Ta channel katsudo den`i kaiseki ni yoru baiyo shinkei kairomonai kofun denpa keiro no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Konno, N.; Fukami, T.; Shiina, T. [University of Tsukuba, Tsukuba (Japan); Jinbo, Y. [Nippon Telegraph and Telephone Corp., Tokyo (Japan)

    1998-07-01

    We have fabricated a 64 embedded microelectrode-array substrate using semiconductor technology to investigate the biological signal processing in brain by using cultured neural networks of fetal rat neocortex in vitro. We analyzed temporal and spatial neural networks patterns cultured on electrode-array substrate and attempted to examine the network structure constituted by neurons and the propagating patterns of electrical activity induced by the electric stimulus. In the experiments, each microelectrode size was 30 {mu}m squared and 150{mu} m spaced. For stimulation, one of the electrodes was selected and current pulses were applied through an isolated circuit. After the network was cultured in about 50 days, responses of neurons to electric stimulus were monitored extracellularly through 64-channel electrode array. Data recorded at each electrode consist of several spike trains generated by different cells. Therefore, these trains were separated by using wavelet transform and template matching for each electrode. We referred the temporal patterns of generated spikes for each electrode to as `spike sequences`. Next, we compared With the spike sequences among multichannel data and visualized the Cultured neural networks structure by identifying the directions of propagations and cell connections. 15 refs., 9 figs.

  4. Knowledge-Sharing Networks in Hunter-Gatherers and the Evolution of Cumulative Culture.

    Science.gov (United States)

    Salali, Gul Deniz; Chaudhary, Nikhil; Thompson, James; Grace, Olwen Megan; van der Burgt, Xander M; Dyble, Mark; Page, Abigail E; Smith, Daniel; Lewis, Jerome; Mace, Ruth; Vinicius, Lucio; Migliano, Andrea Bamberg

    2016-09-26

    Humans possess the unique ability for cumulative culture [1, 2]. It has been argued that hunter-gatherer's complex social structure [3-9] has facilitated the evolution of cumulative culture by allowing information exchange among large pools of individuals [10-13]. However, empirical evidence for the interaction between social structure and cultural transmission is scant [14]. Here we examine the reported co-occurrence of plant uses between individuals in dyads (which we define as their "shared knowledge" of plant uses) in BaYaka Pygmies from Congo. We studied reported uses of 33 plants of 219 individuals from four camps. We show that (1) plant uses by BaYaka fall into three main domains: medicinal, foraging, and social norms/beliefs; (2) most medicinal plants have known bioactive properties, and some are positively associated with children's BMI, suggesting that their use is adaptive; (3) knowledge of medicinal plants is mainly shared between spouses and biological and affinal kin; and (4) knowledge of plant uses associated with foraging and social norms is shared more widely among campmates, regardless of relatedness, and is important for camp-wide activities that require cooperation. Our results show the interdependence between social structure and knowledge sharing. We propose that long-term pair bonds, affinal kin recognition, exogamy, and multi-locality create ties between unrelated families, facilitating the transmission of medicinal knowledge and its fitness implications. Additionally, multi-family camps with low inter-relatedness between camp members provide a framework for the exchange of functional information related to cooperative activities beyond the family unit, such as foraging and regulation of social life. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Social Networking Sites and Self-Promotional Culture. Notes for a Theory of the Mosaic Identity

    Directory of Open Access Journals (Sweden)

    Lucía Caro Castaño

    2017-05-01

    Full Text Available This exploratory work theorizes about how social networking sites favor, as identity technologies, a way of conceiving and presenting individual identity in self-promotional terms. As a result of the normalization of this logic –which is coherent with the late capitalism’ promotional culture–, it is growing the incorporation of self-branding practices in the users's daily communication. Besides, it is increasing the perception of the social profiles as micro-media and the interpretation of the own network as a personal audience. In brief, four main trends in the presentation of identity which are promoted by these web services are identified: a distributed and fragmented conception of the self, where the tiles from mass media become key content to express subjectivity; a tendency to quantify relationships and affections; the perception of being in an unavoidable competition with others; and standardization of the audiovisual presentation of self as a communicative material capable of attracting attention and communicate authenticity.

  6. Dependence of synchronized bursting activity on medium stirring and the perfusion rate in a cultured network of neurons

    Science.gov (United States)

    Heo, Ryoun; Kim, Hyun; Lee, Kyoung J.

    2016-05-01

    A cultured network of neurons coupled with a multi-electrode-array (MEA) recording system has been a useful platform for investigating various issues in neuroscience and engineering. The neural activity supported by the system can be sensitive to environmental fluctuations, for example, in the medium's nutrient composition, ph, and temperature, and to mechanical disturbances, yet this issue has not been the subject. Especially, a normal practice in maintaining neuronal cell cultures involves an intermittent sequence of medium exchanges, typically at a time interval of a few days, and one such sudden medium exchange is unavoidably accompanied by many unintended disturbances. Here, based on a quantitative time-series analysis of synchronized bursting events, we explicitly demonstrate that such a medium exchange can, indeed, bring a huge change in the existing neural activity. Subsequently, we develop a medium perfusion-stirring system and an ideal protocol that can be used in conjunction with a MEA recording system, providing long-term stability. Specifically, we systematically evaluate the effects of medium stirring and perfusion rates. Unexpectedly, even some vigorous mechanical agitations do not have any impacts on neural activity. On the other hand, too much replenishment ( e.g., 1.8 ml/day for a 1.8-ml dish) of neurobasal medium results in an excitotoxicity.

  7. HEPES activates a MiT/TFE-dependent lysosomal-autophagic gene network in cultured cells: A call for caution.

    Science.gov (United States)

    Tol, Marc J; van der Lienden, Martijn J C; Gabriel, Tanit L; Hagen, Jacob J; Scheij, Saskia; Veenendaal, Tineke; Klumperman, Judith; Donker-Koopman, Wilma E; Verhoeven, Arthur J; Overkleeft, Hermen; Aerts, Johannes M; Argmann, Carmen A; van Eijk, Marco

    2018-01-01

    In recent years, the lysosome has emerged as a highly dynamic, transcriptionally regulated organelle that is integral to nutrient-sensing and metabolic rewiring. This is coordinated by a lysosome-to-nucleus signaling nexus in which MTORC1 controls the subcellular distribution of the microphthalmia-transcription factor E (MiT/TFE) family of "master lysosomal regulators". Yet, despite the importance of the lysosome in cellular metabolism, the impact of traditional in vitro culture media on lysosomal dynamics and/or MiT/TFE localization has not been fully appreciated. Here, we identify HEPES, a chemical buffering agent that is broadly applied in cell culture, as a potent inducer of lysosome biogenesis. Supplementation of HEPES to cell growth media is sufficient to decouple the MiT/TFE family members-TFEB, TFE3 and MITF-from regulatory mechanisms that control their cytosolic retention. Increased MiT/TFE nuclear import in turn drives the expression of a global network of lysosomal-autophagic and innate host-immune response genes, altering lysosomal dynamics, proteolytic capacity, autophagic flux, and inflammatory signaling. In addition, siRNA-mediated MiT/TFE knockdown effectively blunted HEPES-induced lysosome biogenesis and gene expression profiles. Mechanistically, we show that MiT/TFE activation in response to HEPES requires its macropinocytic ingestion and aberrant lysosomal storage/pH, but is independent of MTORC1 signaling. Altogether, our data underscore the cautionary use of chemical buffering agents in cell culture media due to their potentially confounding effects on experimental results.

  8. RELIGIOUS NETWORKS IN MADURA Pesantren, Nahdlatul Ulama and Kiai as the Core of Santri Culture

    Directory of Open Access Journals (Sweden)

    Yanwar Pribadi

    2013-07-01

    Full Text Available This paper addresses three institutions in Madurese santri culture: the pesantren (Islamic traditional education system, the Nahdlatul Ulama, and the kiai (tradisional Islamic authority. These three elements have characterised and become central part of both Islam and politics in Madura. The issues are raised in this paper: the nature of pesantren, the role of Nahdlatul Ulama, and kiais within the whole tradition of santri Islam in Madura. How does each of these elements form relationships with the others? These questions lead to answer the main question: Is Islam in Madura different from Islam in other places in Indonesia? Today, it seems clear that despite their rather changed perceptions of modern education, Islamic associations, and men of religion, Madurese people continue to preserve their sacred values, as the main three elements of the santri culture in Madura which have had a great influence on society, in both religious and worldly domains. The people share the view that Islamic law (shari’a is fundamental to daily life and thus must be integrated in all aspects of life. However, like Islam in other places in Indonesia, the characteristic of Islam in Madura emphasises primarily, but not exclusively, on aspects such as mysticism and local cultures. [Artikel ini menjelaskan tiga elemen penting budaya santri yang melekat pada masyarakat Madura, yaitu pesantren, mewakili elemen pendidikan Islam tradisional, Nahdlatul Ulama, mewakili organisasi Islam, dan kiai, merepresentasikan tokoh Islam. Ketiga elemen tersebut berjalin-kelindan dan membentuk relasi yang kompleks antara Islam dan politik sebagaimana dipraktikkan dalam masyarakat Madura. Dua persoalan penting yang hendak dijawab melalui artikel ini yaitu bagaimana karakter pesantren, Nahdlatul Ulama, dan kiai yang menjadi dasar Islam-santri di Madura dan bagaimana ketiga elemen tersebut saling terkait satu sama lain. Persoalan ini kemudian mengantarkan pada pertanyaan penting lainnya

  9. The public space of social media connected cultures of the network society

    CERN Document Server

    Tierney, Therese

    2013-01-01

    Social media is restructuring urban practices-through ad-hoc experimentation, commercial software development, and communities of participation. This book is the first to consider how practices contained within social media are situated within a larger genealogy of public space, including theories of communal identity, civitas and democracy, the fete, and self-expression. Through empirical research, the actual social practices of participants of networked publics are described and analyzed. Documenting how online counterpublics use the Internet to transmit classified photos, mobilize activists, and challenge the status quo, Tierney argues that online activities do not stop in online conversations; they are physically grounded through mobile GPS coordinates which are then transformed into activities in physical space-the street, the plaza, the places where people have traditionally gathered to demonstrate and express their opinions publicly.

  10. Electrical responses and spontaneous activity of human iPS-derived neuronal networks characterized for three-month culture with 4096-electrode arrays

    Directory of Open Access Journals (Sweden)

    Hayder eAmin

    2016-03-01

    Full Text Available The recent availability of human induced pluripotent stem cells (hiPSCs holds great promise as a novel source of human-derived neurons for cell and tissue therapies as well as for in vitro drug screenings that might replace the use of animal models. However, there is still a considerable lack of knowledge on the functional properties of hiPSC-derived neuronal networks, thus limiting their application. Here, upon optimization of cell culture protocols, we demonstrate that both spontaneous and evoked electrical spiking activities of these networks can be characterized on-chip by taking advantage of the resolution provided by CMOS multielectrode arrays (CMOS-MEAs. These devices feature a large and closely-spaced array of 4096 simultaneously recording electrodes and multi-site on-chip electrical stimulation. Our results show that networks of human-derived neurons can respond to electrical stimulation with a physiological repertoire of spike waveforms after three months of cell culture, a period of time during which the network undergoes the expression of developing patterns of spontaneous spiking activity. To achieve this, we have investigated the impact on the network formation and on the emerging network-wide functional properties induced by different biochemical substrates, i.e. poly-dl-ornithine (PDLO, poly-l-ornithine (PLO, and polyethylenimine (PEI, that were used as adhesion promoters for the cell culture. Interestingly, we found that neuronal networks grown on PDLO coated substrates show significantly higher spontaneous firing activity, reliable responses to low-frequency electrical stimuli, and an appropriate level of PSD-95 that may denote a physiological neuronal maturation profile and synapse stabilization. However, our results also suggest that even three-month culture might not be sufficient for human-derived neuronal network maturation. Taken together, our results highlight the tight relationship existing between substrate coatings

  11. Networking

    OpenAIRE

    Rauno Lindholm, Daniel; Boisen Devantier, Lykke; Nyborg, Karoline Lykke; Høgsbro, Andreas; Fries, de; Skovlund, Louise

    2016-01-01

    The purpose of this project was to examine what influencing factor that has had an impact on the presumed increasement of the use of networking among academics on the labour market and how it is expressed. On the basis of the influence from globalization on the labour market it can be concluded that the globalization has transformed the labour market into a market based on the organization of networks. In this new organization there is a greater emphasis on employees having social qualificati...

  12. Remote assessment of cultural heritage environments with wireless sensor array networks.

    Science.gov (United States)

    Agbota, Henoc; Mitchell, John E; Odlyha, Marianne; Strlič, Matija

    2014-05-19

    The logistics and cost of environmental monitoring can represent challenges for heritage managers, partly because of the sheer number of environmental parameters to consider. There is a need for a system, capable of monitoring the holistic impact of the environment on cultural materials while remaining relatively easy to use and providing remote access. This paper describes a dosimetric system based on piezoelectric quartz crystal technology. The prototype sensing module consists of an array of piezoelectric quartz crystals (PQC) coated with different metals (Fe, Cu, Ni and Sn) and includes a temperature and relative humidity sensor. The communication module involves an 802.15.4 low-power radio and a GPRS gateway which allows real time visualisation of the measurements online. An energy management protocol ensures that the system consumes very low power between measurements. The paper also describes the results and experiences from two heritage field deployments, at Apsley House in London, UK, and at the Royal Palaces of Abomey in Benin. Evaluation of PQC measurements, temperature, relative humidity and the rate of successful transmission over the communication systems are also reported.

  13. Temporal and spatial differences in intracellular Ca++ changes elicited by K+ and glutamate in single cultured neocortical neurons

    DEFF Research Database (Denmark)

    Belhage, B; Frandsen, A; Schousboe, A

    1996-01-01

    characteristics of voltage gated Ca++ channels are dramatically different in cell bodies and neurites. Moreover, the distribution of L-type channels activated by glutamate differs in cell bodies and neurites. Such differences in the spatial distribution of Ca++ channels are likely to be of major importance...... after exposure to K+. The Ca++ channel blockers verapamil and nifedipine affecting N- and L-type channels, respectively had differential effects on K+ stimulated increases in [Ca++]i. Nifedipine only affected the increase marginally whereas verapamil inhibited the response by 50-60% both in cell bodies...

  14. Legal Analysis of Constructing Network Security System --View of Network Security Culture%建立网络安全保障体系的法律思考——以网络安全文化为视角

    Institute of Scientific and Technical Information of China (English)

    王铁占; 安海兴

    2011-01-01

    The information network movement system frequency suffers the destruction, has the value information to steal repeatedly, is main threat which the current network security faces. Under the network security culture frame, through legislation, establishes the stan perfect network security legal li government by law function and be an urgent matter. the enhancement networking legislation and the safety control administration dard network security service industry development the legal framework, the ability system, raises the network user safety idea, the display morals in the so on, the establishment should to the threat network security safeguard system%信息网络运行系统频遭破坏导致有价值信息屡被窃取,是当前网络安全面临的主要威胁。在网络安全文化框架下,通过加强网络技术立法与安全管理行政立法,建立规范网络安全服务业发展的法律体系,完善网络安全法律责任制度,培养网络用户安全理念,发挥道德在法治中的作用,建立应对威胁的网络安全保障体系是当务之急。

  15. Tcf3 represses Wnt-β-catenin signaling and maintains neural stem cell population during neocortical development.

    Directory of Open Access Journals (Sweden)

    Atsushi Kuwahara

    Full Text Available During mouse neocortical development, the Wnt-β-catenin signaling pathway plays essential roles in various phenomena including neuronal differentiation and proliferation of neural precursor cells (NPCs. Production of the appropriate number of neurons without depletion of the NPC population requires precise regulation of the balance between differentiation and maintenance of NPCs. However, the mechanism that suppresses Wnt signaling to prevent premature neuronal differentiation of NPCs is poorly understood. We now show that the HMG box transcription factor Tcf3 (also known as Tcf7l1 contributes to this mechanism. Tcf3 is highly expressed in undifferentiated NPCs in the mouse neocortex, and its expression is reduced in intermediate neuronal progenitors (INPs committed to the neuronal fate. We found Tcf3 to be a repressor of Wnt signaling in neocortical NPCs in a reporter gene assay. Tcf3 bound to the promoter of the proneural bHLH gene Neurogenin1 (Neurog1 and repressed its expression. Consistent with this, Tcf3 repressed neuronal differentiation and increased the self-renewal activity of NPCs. We also found that Wnt signal stimulation reduces the level of Tcf3, and increases those of Tcf1 (also known as Tcf7 and Lef1, positive mediators of Wnt signaling, in NPCs. Together, these results suggest that Tcf3 antagonizes Wnt signaling in NPCs, thereby maintaining their undifferentiated state in the neocortex and that Wnt signaling promotes the transition from Tcf3-mediated repression to Tcf1/Lef1-mediated enhancement of Wnt signaling, constituting a positive feedback loop that facilitates neuronal differentiation.

  16. Comparison of practice based research network based quality improvement technical assistance and evaluation to other ongoing quality improvement efforts for changes in agency culture.

    Science.gov (United States)

    Livingood, William C; Peden, Angela H; Shah, Gulzar H; Marshall, Nandi A; Gonzalez, Ketty M; Toal, Russell B; Alexander, Dayna S; Wright, Alesha R; Woodhouse, Lynn D

    2015-07-31

    Public health agencies in the USA are increasingly challenged to adopt Quality Improvement (QI) strategies to enhance performance. Many of the functional and structural barriers to effective use of QI can be found in the organizational culture of public health agencies. The purpose of this study was to assess the impact of public health practice based research network (PBRN) evaluation and technical assistance for QI interventions on the organizational culture of public health agencies in Georgia, USA. An online survey of key informants in Georgia's districts and county health departments was used to compare perceptions of characteristics of organizational QI culture between PBRN supported QI districts and non-PBRN supported districts before and after the QI interventions. The primary outcomes of concern were number and percentage of reported increases in characteristics of QI culture as measured by key informant responses to items assessing organizational QI practices from a validated instrument on QI Collaboratives. Survey results were analyzed using Multi-level Mixed Effects Logistic Model, which accounts for clustering/nesting. Increases in QI organizational culture were consistent for all 10- items on a QI organizational culture survey related to: leadership support, use of data, on-going QI, and team collaboration. Statistically significant odds ratios were calculated for differences in increased QI organizational culture between PBRN-QI supported districts compared to Non-PBRN supported districts for 5 of the 10 items, after adjusting for District clustering of county health departments. Agency culture, considered by many QI experts as the main goal of QI, is different than use of specific QI methods, such as Plan-Do-Study-Act (PDSA) cycles or root-cause analyses. The specific use of a QI method does not necessarily reflect culture change. Attempts to measure QI culture are newly emerging. This study documented significant improvements in characteristics of

  17. Mapping thalamocortical network pathology in temporal lobe epilepsy.

    Science.gov (United States)

    Bernhardt, Boris C; Bernasconi, Neda; Kim, Hosung; Bernasconi, Andrea

    2012-01-10

    Although experimental work has provided evidence that the thalamus is a crucial relay structure in temporal lobe epilepsy (TLE), the relation of the thalamus to neocortical pathology remains unclear. To assess thalamocortical network pathology in TLE, we mapped pointwise patterns of thalamic atrophy and statistically related them to neocortical thinning. We studied cross-sectionally 36 patients with drug-resistant TLE and 19 age- and sex-matched healthy control subjects using high-resolution MRI. To localize thalamic pathology, we converted manual labels into surface meshes using the spherical harmonic description and calculated local deformations relative to a template. In addition, we measured cortical thickness by means of the constrained Laplacian anatomic segmentation using proximity algorithm. Compared with control subjects, patients with TLE showed ipsilateral thalamic atrophy that was located along the medial surface, encompassing anterior, medial, and posterior divisions. Unbiased analysis correlating the degree of medial thalamic atrophy with cortical thickness measurements mapped bilateral frontocentral, lateral temporal, and mesiotemporal cortices. These areas overlapped with those of cortical thinning found when patients were compared with control subjects. Thalamic atrophy intensified with a longer duration of epilepsy and was more severe in patients with a history of febrile convulsions. The degree and distribution of thalamic pathology relates to the topography and extent of neocortical atrophy, lending support to the concept that the thalamus is an important hub in the pathologic network of TLE.

  18. Mechanisms of memory storage in a model perirhinal network.

    Science.gov (United States)

    Samarth, Pranit; Ball, John M; Unal, Gunes; Paré, Denis; Nair, Satish S

    2017-01-01

    The perirhinal cortex supports recognition and associative memory. Prior unit recording studies revealed that recognition memory involves a reduced responsiveness of perirhinal cells to familiar stimuli whereas associative memory formation is linked to increasing perirhinal responses to paired stimuli. Both effects are thought to depend on perirhinal plasticity but it is unclear how the same network could support these opposite forms of plasticity. However, a recent study showed that when neocortical inputs are repeatedly activated, depression or potentiation could develop, depending on the extent to which the stimulated neocortical activity recruited intrinsic longitudinal connections. We developed a biophysically realistic perirhinal model that reproduced these phenomena and used it to investigate perirhinal mechanisms of associative memory. These analyzes revealed that associative plasticity is critically dependent on a specific subset of neurons, termed conjunctive cells (CCs). When the model network was trained with spatially distributed but coincident neocortical inputs, CCs acquired excitatory responses to the paired inputs and conveyed them to distributed perirhinal sites via longitudinal projections. CC ablation during recall abolished expression of the associative memory. However, CC ablation during training did not prevent memory formation because new CCs emerged, revealing that competitive synaptic interactions governs the formation of CC assemblies.

  19. An Exploration of Professional Culture Differentials and Their Potential Impact on the Information Assurance Component of Optical Transmission Networks Design

    Science.gov (United States)

    Cuthrell, Michael Gerard

    2011-01-01

    Optical transmission networks are an integral component of the critical infrastructures for many nations. Many people believe that optical transmission networks are impenetrable. In actuality, these networks possess weaknesses that can be exploited to bring about harm. An emerging Information Assurance (IA) industry has as its goals: to…

  20. Seamless Combination of Fluorescence-Activated Cell Sorting and Hanging-Drop Networks for Individual Handling and Culturing of Stem Cells and Microtissue Spheroids.

    Science.gov (United States)

    Birchler, Axel; Berger, Mischa; Jäggin, Verena; Lopes, Telma; Etzrodt, Martin; Misun, Patrick Mark; Pena-Francesch, Maria; Schroeder, Timm; Hierlemann, Andreas; Frey, Olivier

    2016-01-19

    Open microfluidic cell culturing devices offer new possibilities to simplify loading, culturing, and harvesting of individual cells or microtissues due to the fact that liquids and cells/microtissues are directly accessible. We present a complete workflow for microfluidic handling and culturing of individual cells and microtissue spheroids, which is based on the hanging-drop network concept: The open microfluidic devices are seamlessly combined with fluorescence-activated cell sorting (FACS), so that individual cells, including stem cells, can be directly sorted into specified culturing compartments in a fully automated way and at high accuracy. Moreover, already assembled microtissue spheroids can be loaded into the microfluidic structures by using a conventional pipet. Cell and microtissue culturing is then performed in hanging drops under controlled perfusion. On-chip drop size control measures were applied to stabilize the system. Cells and microtissue spheroids can be retrieved from the chip by using a parallelized transfer method. The presented methodology holds great promise for combinatorial screening of stem-cell and multicellular-spheroid cultures.

  1. Sustained release of stem cell factor in a double network hydrogel for ex vivo culture of cord blood-derived CD34+ cells.

    Science.gov (United States)

    Zhang, Yuanhao; Pan, Xiuwei; Shi, Zhen; Cai, Haibo; Gao, Yun; Zhang, Weian

    2018-04-01

    Stem cell factor (SCF) is considered as a commonly indispensable cytokine for proliferation of haematopoietic stem cells (HSCs), which is used in large dosages during ex vivo culture. The work presented here aimed to reduce the consumption of SCF by sustained release but still support cells proliferation and maintain the multipotency of HSCs. Stem cell factor was physically encapsulated within a hyaluronic acid/gelatin double network (HGDN) hydrogel to achieve a slow release rate. CD34 + cells were cultured within the SCF-loaded HGDN hydrogel for 14 days. The cell number, phenotype and functional capacity were investigated after culture. The HGDN hydrogels had desirable properties and encapsulated SCF kept being released for more than 6 days. SCF remained the native bioactivity, and the proliferation of HSCs within the SCF-loaded HGDN hydrogel was not affected, although the consumption of SCF was only a quarter in comparison with the conventional culture. Moreover, CD34 + cells harvested from the SCF-loaded HGDN hydrogels generated more multipotent colony-forming units (CFU-GEMM). The data suggested that the SCF-loaded HGDN hydrogel could support ex vivo culture of HSCs, thus providing a cost-effective culture protocol for HSCs. © 2017 John Wiley & Sons Ltd.

  2. Mutual exchange between Polish and Belgian magazines: a case study in cultural mobility within the interwar network of the avant-garde

    Directory of Open Access Journals (Sweden)

    Michał Wenderski

    2015-07-01

    Full Text Available In January 1924, Flemish avant-garde magazine Het Overzicht published a list of its congenial modernist for­ma­tions named ‘Het Netwerk’. It named nineteen magazines from Europe, the United States and Brazil, including the Polish magazine Zwrotnica. It exemplified the close and direct relationships within the supranational network of the avant-garde. Various formations belonging to this network, both bigger and smaller nodes, were linked to each other, often directly through befriended artists and writers. It did not only concern places such as Paris or Berlin, but also less pivotal nodes of the avant-garde network. In this paper I will present a case study of two countries, namely Poland and Belgium, as an example of European interwar cultural mobility. Joined in their pursuit of modern art, and crossing national and linguistic frontiers, Polish, French and Dutch-language magazines exchanged and re-printed each other’s texts and artworks, a practice also discussed in the correspondence between their representatives. Based on such tangible traces I will describe the cultural mobility and mutual exchange between the Polish and Belgian modernist journals, and attempt to shed light on the features, dynamics, and key figures of the network.

  3. In vitro co-cultures of human gut bacterial species as predicted from co-occurrence network analysis

    DEFF Research Database (Denmark)

    Das, Promi; Ji, Boyang; Kovatcheva-Datchary, Petia

    2018-01-01

    Network analysis of large metagenomic datasets generated by current sequencing technologies can reveal significant co-occurrence patterns between microbial species of a biological community. These patterns can be analyzed in terms of pairwise combinations between all species comprising a community...... thetaiotaomicron, as well as Faecalibacterium prausnitzii and Roseburia inulinivorans as model organisms for our study. We then delineate the outcome of the co-cultures when equal distributions of resources were provided. The growth behavior of the co-culture was found to be dependent on the types of microbial...... species present, their specific metabolic activities, and resulting changes in the culture environment. Through this reductionist approach and using novel in vitro combinations of microbial species under anaerobic conditions, the results of this work will aid in the understanding and design of synthetic...

  4. ­La restructuration du réseau culturel français au quotidien The everyday reconstruction of French cultural network La reestructuración cotidiana de la red cultural francesa

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    Christophe Premat

    2013-03-01

    Full Text Available Il s’agit de comprendre les transformations des conditions du métier d’agent culturel à la lumière des réformes en cours du réseau culturel français. La restructuration des activités culturelles des Instituts est-elle le signe d’une privatisation de l’action culturelle extérieure de l’État ? La coopération culturelle serait-elle alors prise en charge par d’autres acteurs ? Afin de répondre à ces questions, l’article s’appuie sur une étude de cas, celle de l’Institut français de Stockholm, qui a abandonné une partie de ses activités au profit d’autres actions de coopération.The article tries to understand how current reforms of the French cultural network might transform the profession of cultural agent. The question is whether the restructuring of cultural institutes’ cultural activities reflects a privatization of the State’s external cultural action, and if other actors might then assume responsibility for cultural cooperation. It responds with a case study of the French cultural centre in Stockholm, which gave up a part of its activities to adopt other cooperation actions.En este trabajo tratamos de comprender las transformaciones de las condiciones del oficio de agente cultural a la luz de las reformas actuales en la red cultural francesa. ¿Es la reestructuración de las actividades culturales de los Institutos el signo de una privatización de la acción cultural exterior del Estado ? ¿Otros actores tomarían entonces en sus manos la cooperación cultural ? Con el fin de responder a esas preguntas, el artículo se apoya en un estudio de caso realizado por el Instituto francés de Estocolmo, el cual abandonó una parte de sus actividades para encargarse de otras acciones de cooperación.

  5. AMPA receptor mediated excitotoxicity in neocortical neurons is developmentally regulated and dependent upon receptor desensitization

    DEFF Research Database (Denmark)

    Jensen, J B; Schousboe, A; Pickering, D S

    1998-01-01

    with a fast and rapidly desensitizing response, this could explain the relatively low toxicity produced by 500 microM AMPA. This was investigated by blocking AMPA receptor desensitization with cyclothiazide. Using a lower concentration (25 microM) of AMPA, addition of 50 microM cyclothiazide increased...... the AMPA induced excitotoxicity in cultured cortical neurons at all DIV except for DIV 2. This combination of AMPA + cyclothiazide yielded 77% cell death for DIV 12 cultures. In contrast to the results observed with 500 microM AMPA, the neurotoxicity mediated directly by AMPA receptors when desensitization...

  6. Statistical adjustment of culture-independent diagnostic tests for trend analysis in the Foodborne Diseases Active Surveillance Network (FoodNet), USA.

    Science.gov (United States)

    Gu, Weidong; Dutta, Vikrant; Patrick, Mary; Bruce, Beau B; Geissler, Aimee; Huang, Jennifer; Fitzgerald, Collette; Henao, Olga

    2018-03-19

    Culture-independent diagnostic tests (CIDTs) are increasingly used to diagnose Campylobacter infection in the Foodborne Diseases Active Surveillance Network (FoodNet). Because CIDTs have different performance characteristics compared with culture, which has been used historically and is still used to diagnose campylobacteriosis, adjustment of cases diagnosed by CIDT is needed to compare with culture-confirmed cases for monitoring incidence trends. We identified the necessary parameters for CIDT adjustment using culture as the gold standard, and derived formulas to calculate positive predictive values (PPVs). We conducted a literature review and meta-analysis to examine the variability in CIDT performance and Campylobacter prevalence applicable to FoodNet sites. We then developed a Monte Carlo method to estimate test-type and site-specific PPVs with their associated uncertainties. The uncertainty in our estimated PPVs was largely derived from uncertainty about the specificity of CIDTs and low prevalence of Campylobacter in tested samples. Stable CIDT-adjusted incidences of Campylobacter cases from 2012 to 2015 were observed compared with a decline in culture-confirmed incidence. We highlight the lack of data on the total numbers of tested samples as one of main limitations for CIDT adjustment. Our results demonstrate the importance of adjusting CIDTs for understanding trends in Campylobacter incidence in FoodNet.

  7. Korean immigrants don't buy health insurance: The influences of culture on self-employed Korean immigrants focusing on structure and functions of social networks.

    Science.gov (United States)

    Oh, Hyunsung; Jeong, Chung Hyeon

    2017-10-01

    Culture has been pinpointed as a culprit of disparities in health insurance coverage between Korean immigrants and other ethnic groups. This study explored specific mechanisms by which culture influences a decision to buy health insurance among self-employed Korean immigrants living in ethnic enclaves by focusing on the structure and functions of social networks. Between March and June 2015, we recruited 24 Korean immigrant adults (aged 18 or older) who identified as self-employed and being uninsured for substantial periods before 2014 in Southern California. Interviews were conducted in Korean, and Korean transcripts were translated into English by two bilingual interpreters. Using constant comparative analysis, we explored why participants didn't purchase health insurance after migrating to the United States and how their social networks influenced their decisions whether to purchase health insurance. Results indicate Korean immigrants sought health information from dense and homogeneous social networks whose members are mostly Korean immigrants embedded in similar social contexts. Social learning was frequently observed when people sought health care while uninsured. However, respondents often noted social ties do not provide helpful information about benefits, costs, and ways to use health insurance. "Koreans don't buy health insurance" was a dominant social norm reported by most respondents. Findings indicate that social learning and normative influence occur inside social networks and these mechanisms seemingly prevent purchasing of health insurance. In addition to the individual mandate in the Patient Protection and Affordable Care Act, more targeted approaches that consider the structure and functions of social networks could improve the public health of Korean immigrants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy.

    Science.gov (United States)

    Neubauer, Florian B; Sederberg, Audrey; MacLean, Jason N

    2014-01-01

    During the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant structures into epileptiform discharges. Further, it is not known whether aberrant areas recruit or entrain healthy ones into pathological activity. Here we study the dynamics of local circuit activity during the spread of epileptiform discharges in the zero-magnesium in vitro model of epilepsy. We employ high-speed multi-photon imaging in combination with dual whole-cell recordings in acute thalamocortical (TC) slices of the juvenile mouse to characterize the generalization of epileptic activity between neocortex and thalamus. We find that, although both structures are exposed to zero-magnesium, the initial onset of focal epileptiform discharge occurs in cortex. This suggests that local recurrent connectivity that is particularly prevalent in cortex is important for the initiation of seizure activity. Subsequent recruitment of thalamus into joint, generalized discharges is coincident with an increase in the coherence of local cortical circuit activity that itself does not depend on thalamus. Finally, the intensity of population discharges is positively correlated between both brain areas. This suggests that during and after seizure generalization not only the timing but also the amplitude of epileptiform discharges in thalamus is entrained by cortex. Together these results suggest a central role of neocortical activity for the onset and the structure of pathological recruitment of thalamus into joint synchronous epileptiform discharges.

  9. HERC 1 ubiquitin ligase mutation affects neocortical, CA3 hippocampal and spinal cord projection neurons. An ultrastructural study

    Directory of Open Access Journals (Sweden)

    Rocío eRuiz

    2016-04-01

    Full Text Available The spontaneous mutation tambaleante is caused by the Gly483Glu substitution in the highly conserved N terminal RCC1-like domain of the HERC1 protein, which leads to the increase of mutated protein levels responsible for cerebellar Purkinje cell death by autophagy. Until now, Purkinje cells have been the only central nervous neurons reported as being targeted by the mutation, and their degeneration elicits an ataxic syndrome in adult mutant mice. However, the ultrastructural analysis performed here demonstrates that signs of autophagy, such as autophagosomes, lysosomes, and altered mitochondria, are present in neocortical pyramidal, CA3 hippocampal pyramidal, and spinal cord motor neurons. The main difference is that the reduction in the number of neurons affected in the tambaleante mutation in the neocortex, the hippocampus, and the spinal cord is not so evident as the dramatic loss of cerebellar Purkinje cells. Interestingly, signs of autophagy are absent in both interneurons and neuroglia cells. Affected neurons have in common that they are projection neurons which receive strong and varied synaptic inputs, and possess the highest degree of neuronal activity. Therefore, because the integrity of the ubiquitin-proteasome system is essential for protein degradation and, hence, for normal protein turnover, it could be hypothesized that the deleterious effects of the misrouting of these pathways would depend directly on the neuronal activity.

  10. Optogenetic activation of neocortical neurons in vivo with a sapphire-based micro-scale LED probe

    Directory of Open Access Journals (Sweden)

    Niall eMcAlinden

    2015-05-01

    Full Text Available Optogenetics has proven to be a revolutionary technology in neuroscience and has advanced continuously over the past decade. However, optical stimulation technologies for in vivo need to be developed to match the advances in genetics and biochemistry that have driven this field. In particular, conventional approaches for in vivo optical illumination have a limitation on the achievable spatio-temporal resolution. Here we utilize a sapphire-based microscale gallium nitride light-emitting diode (µLED probe to activate neocortical neurons in vivo. The probes were designed to contain independently controllable multiple µLEDs, emitting at 450 nm wavelength with an irradiance of up to 2 W/mm2. Monte-Carlo stimulations predicted that optical stimulation using a µLED can modulate neural activity within a localized region. To validate this prediction, we tested this probe in the mouse neocortex that expressed channelrhodopsin-2 (ChR2 and compared the results with optical stimulation through a fiber at the cortical surface. We confirmed that both approaches reliably induced action potentials in cortical neurons and that the µLED probe evoked strong responses in deep neurons. Due to the possibility to integrate many optical stimulation sites onto a single shank, the µLED probe is thus a promising approach to control neurons locally in vivo.

  11. The Roles of Religious Culture and Moral Knowledge Teachers in Organizing Their Students Relationships with Social Networks

    Science.gov (United States)

    Turan, Emine Zehra; Isçitürk, Gökçe Becit

    2017-01-01

    In parallel to the improvements experienced in information and communication systems in recent years, any use of Internet, especially the social networks by children and adolescents has been noticed to be increasing gradually. Use of social networks that starts at early ages has exposed children to some dangers. For that reason, the responsibility…

  12. The UK-SEA-ME Psychosocial-Cultural Cancer Research Network: setting the stage for applied qualitative research on cancer health behaviour in southeast Asia and the Middle East.

    Science.gov (United States)

    Lim, Jennifer N W

    2011-01-01

    Psychosocial and cultural factors influencing cancer health behaviour have not been systematically investigated outside the western culture, and qualitative research is the best approach for this type of social research. The research methods employed to study health problems in Asia predominantly are quantitative techniques. The set up of the first psychosocial cancer research network in Asia marks the beginning of a collaboration to promote and spearhead applied qualitative healthcare research in cancer in the UK, Southeast Asia and the Middle East. This paper sets out the rationale, objectives and mission for the UK-SEA-ME Psychosocial-Cultural Cancer Research Network. The UK-SEA-ME network is made up of collaborators from the University of Leeds (UK), the University of Malaya (Malaysia), the National University of Singapore (Singapore) and the University of United Arab Emirates (UAE). The network promotes applied qualitative research to investigate the psychosocial and cultural factors influencing delayed and late presentation and diagnosis for cancer (breast cancer) in partner countries, as well as advocating the use of the mixed-methods research approach. The network also offers knowledge transfer for capacity building within network universities. The mission of the network is to improve public awareness about the importance of early management and prevention of cancer through research in Asia.

  13. Role of socio-cultural and economic factors in cyprinid fish distribution networks and consumption in Lawa Lake region, Northeast Thailand: Novel perspectives on Opisthorchis viverrini transmission dynamics.

    Science.gov (United States)

    Kim, Christina Sunyoung; Smith, John F; Suwannatrai, Apiporn; Echaubard, Pierre; Wilcox, Bruce; Kaewkes, Sasithorn; Sithithaworn, Paiboon; Sripa, Banchob

    2017-06-01

    Opisthorchis viverrini (Ov) is a fish-borne parasite endemic in parts of Lao PDR, Cambodia, southern Vietnam and Northeast Thailand (Isaan) where an estimated 10 million people are infected. Human Ov infection, associated with hepatobiliary complications, including cholangiocarcinoma (CCA), occurs when infected fish are consumed raw or undercooked, a longstanding cultural tradition in the region. This mixed- methods descriptive study was carried out in Isaan villages around Lawa Lake, Khon Kaen Province, known for their Ov endemicity. Focus group discussions (FGDs) and in depth interviews (IDIs) were used to explore socio-cultural determinants underlying raw fish consumption practices, and global positioning system (GPS) devices to map local fish distribution networks. Qualitative data affirmed major socio-cultural and dietary lifestyle transitions occurring consequent on recent decades of modernization policies and practices, but also the persistence of Isaan traditional raw-fish eating practices and incorrect beliefs about infection risk avoidance. Fish traders/middlemen purchase most of the catch at the lakeshore and play the dominant role in district market fish distribution networks, at least for the larger and less likely infected, fish species. The lower economic value of the small potentially-infected cyprinid fish means local fishermen typically distribute them free, or sell cheaply, to family and friends, effectively concentrating infection risk in already highly Ov infected villages. Our study confirmed the persistence of traditional Isaan raw-fish meal practices, despite major ongoing socio-cultural lifestyle transitions and decades of Ov infection health education programs. We contend that diffuse socio-cultural drivers underpin this practice, including its role as a valued cultural identity marker. A "fish economics" factor was also evident in the concentration of more likely infected fish back into local villages due to their low economic value at

  14. Network Ambivalence

    Directory of Open Access Journals (Sweden)

    Patrick Jagoda

    2015-08-01

    Full Text Available The language of networks now describes everything from the Internet to the economy to terrorist organizations. In distinction to a common view of networks as a universal, originary, or necessary form that promises to explain everything from neural structures to online traffic, this essay emphasizes the contingency of the network imaginary. Network form, in its role as our current cultural dominant, makes scarcely imaginable the possibility of an alternative or an outside uninflected by networks. If so many things and relationships are figured as networks, however, then what is not a network? If a network points towards particular logics and qualities of relation in our historical present, what others might we envision in the future? In  many ways, these questions are unanswerable from within the contemporary moment. Instead of seeking an avant-garde approach (to move beyond networks or opting out of networks (in some cases, to recover elements of pre-networked existence, this essay proposes a third orientation: one of ambivalence that operates as a mode of extreme presence. I propose the concept of "network aesthetics," which can be tracked across artistic media and cultural forms, as a model, style, and pedagogy for approaching interconnection in the twenty-first century. The following essay is excerpted from Network Ambivalence (Forthcoming from University of Chicago Press. 

  15. Association of Plasma Neurofilament Light Chain with Neocortical Amyloid-β Load and Cognitive Performance in Cognitively Normal Elderly Participants.

    Science.gov (United States)

    Chatterjee, Pratishtha; Goozee, Kathryn; Sohrabi, Hamid R; Shen, Kaikai; Shah, Tejal; Asih, Prita R; Dave, Preeti; ManYan, Candice; Taddei, Kevin; Chung, Roger; Zetterberg, Henrik; Blennow, Kaj; Martins, Ralph N

    2018-01-01

    The disruption of neurofilament, an axonal cytoskeletal protein, in neurodegenerative conditions may result in neuronal damage and its release into the cerebrospinal fluid and blood. In Alzheimer's disease (AD), neurofilament light chain (NFL), a neurofilament subunit, is elevated in the cerebrospinal fluid and blood. Investigate the association of plasma NFL with preclinical-AD features, such as high neocortical amyloid-β load (NAL) and subjective memory complaints, and cognitive performance in cognitively normal older adults. Plasma NFL concentrations were measured employing the single molecule array platform in participants from the Kerr Anglican Retirement Village Initiative in Ageing Health cohort, aged 65- 90 years. Participants underwent a battery of neuropsychological testing to evaluate cognitive performance and were categorized as low NAL (NAL-, n = 65) and high NAL (NAL+, n = 35) assessed via PET, and further stratified into subjective memory complainers (SMC; nNAL- = 51, nNAL+ = 25) and non-SMC (nNAL- = 14, nNAL+ = 10) based on the Memory Assessment Clinic- Questionnaire. Plasma NFL inversely correlated with cognitive performance. No significant difference in NFL was observed between NAL+ and NAL- participants; however, within APOEɛ4 non-carriers, higher NAL was observed in individuals with NFL concentrations within quartiles 3 and 4 (versus quartile 1). Additionally, within the NAL+ participants, SMC had a trend of higher NFL compared to non-SMC. Plasma NFL is inversely associated with cognitive performance in elderly individuals. While plasma NFL may not reflect NAL in individuals with normal global cognition, the current observations indicate that onset of axonal injury, reflected by increased plasma NFL, within the preclinical phase of AD may contribute to the pathogenesis of AD.

  16. Heteromeric Kv7.2/7.3 channels differentially regulate action potential initiation and conduction in neocortical myelinated axons.

    Science.gov (United States)

    Battefeld, Arne; Tran, Baouyen T; Gavrilis, Jason; Cooper, Edward C; Kole, Maarten H P

    2014-03-05

    Rapid energy-efficient signaling along vertebrate axons is achieved through intricate subcellular arrangements of voltage-gated ion channels and myelination. One recently appreciated example is the tight colocalization of K(v)7 potassium channels and voltage-gated sodium (Na(v)) channels in the axonal initial segment and nodes of Ranvier. The local biophysical properties of these K(v)7 channels and the functional impact of colocalization with Na(v) channels remain poorly understood. Here, we quantitatively examined K(v)7 channels in myelinated axons of rat neocortical pyramidal neurons using high-resolution confocal imaging and patch-clamp recording. K(v)7.2 and 7.3 immunoreactivity steeply increased within the distal two-thirds of the axon initial segment and was mirrored by the conductance density estimates, which increased from ~12 (proximal) to 150 pS μm(-2) (distal). The axonal initial segment and nodal M-currents were similar in voltage dependence and kinetics, carried by K(v)7.2/7.3 heterotetramers, 4% activated at the resting membrane potential and rapidly activated with single-exponential time constants (~15 ms at 28 mV). Experiments and computational modeling showed that while somatodendritic K(v)7 channels are strongly activated by the backpropagating action potential to attenuate the afterdepolarization and repetitive firing, axonal K(v)7 channels are minimally recruited by the forward-propagating action potential. Instead, in nodal domains K(v)7.2/7.3 channels were found to increase Na(v) channel availability and action potential amplitude by stabilizing the resting membrane potential. Thus, K(v)7 clustering near axonal Na(v) channels serves specific and context-dependent roles, both restraining initiation and enhancing conduction of the action potential.

  17. Increasing research capacity and changing the culture of primary care towards reflective inquiring practice: the experience of the West London Research Network (WeLReN).

    Science.gov (United States)

    Thomas, P; While, A

    2001-05-01

    A number of primary care research networks were set up throughout England in 1998 in order to (1) improve the quality of primary care research (2) increase the research capacity of primary care, and (3) change the culture of primary care towards reflective inquiring practice (NHSE, 2000b). It is not clear how best to operate a network to achieve these diverse aims. This paper describes the first 30 months of a network that adopted a whole system approach in the belief that this would offer the best chance of simultaneously achieving the three aims. A cycle of activity was designed to facilitate the formation of multidisciplinary coalitions of interest for research with complementary 'top down' and 'bottom up' programmes of work co-existing. At least 330 people participated in the generation of research questions of whom one third (33%) were general practitioners, 16% community nurses, 6% practice managers and other primary care practitioners. Over two fifths (43%) were 'key allies'--academics, health authority staff, community workers and project workers. One fifth (110) of all practices (500) in the WeLReN area have collaborated in at least one research project. The ratio of doctor:nurse participation in the 24 research project teams was markedly different in the supported coalitions (2:1) compared to projects devised and led by more experienced researchers (6:1). The evidence suggests that it is possible to operate a primary care research network in a way that develops coalitions of interest from different parts of the health care system as well as both 'top down' and 'bottom up' led projects. It is too early to tell if the approach will be able to achieve its aims in the long-term but the activity data are encouraging. There is a need for more research on the theoretical basis of network operation.

  18. Novel chemometric strategy based on the application of artificial neural networks to crossed mixture design for the improvement of recombinant protein production in continuous culture.

    Science.gov (United States)

    Didier, Caroline; Forno, Guillermina; Etcheverrigaray, Marina; Kratje, Ricardo; Goicoechea, Héctor

    2009-09-21

    The optimal blends of six compounds that should be present in culture media used in recombinant protein production were determined by means of artificial neural networks (ANN) coupled with crossed mixture experimental design. This combination constitutes a novel approach to develop a medium for cultivating genetically engineered mammalian cells. The compounds were collected in two mixtures of three elements each, and the experimental space was determined by a crossed mixture design. Empirical data from 51 experimental units were used in a multiresponse analysis to train artificial neural networks which satisfy different requirements, in order to define two new culture media (Medium 1 and Medium 2) to be used in a continuous biopharmaceutical production process. These media were tested in a bioreactor to produce a recombinant protein in CHO cells. Remarkably, for both predicted media all responses satisfied the predefined goals pursued during the analysis, except in the case of the specific growth rate (mu) observed for Medium 1. ANN analysis proved to be a suitable methodology to be used when dealing with complex experimental designs, as frequently occurs in the optimization of production processes in the biotechnology area. The present work is a new example of the use of ANN for the resolution of a complex, real life system, successfully employed in the context of a biopharmaceutical production process.

  19. Enhanced Sensitivity to Rapid Input Fluctuations by Nonlinear Threshold Dynamics in Neocortical Pyramidal Neurons.

    Science.gov (United States)

    Mensi, Skander; Hagens, Olivier; Gerstner, Wulfram; Pozzorini, Christian

    2016-02-01

    The way in which single neurons transform input into output spike trains has fundamental consequences for network coding. Theories and modeling studies based on standard Integrate-and-Fire models implicitly assume that, in response to increasingly strong inputs, neurons modify their coding strategy by progressively reducing their selective sensitivity to rapid input fluctuations. Combining mathematical modeling with in vitro experiments, we demonstrate that, in L5 pyramidal neurons, the firing threshold dynamics adaptively adjust the effective timescale of somatic integration in order to preserve sensitivity to rapid signals over a broad range of input statistics. For that, a new Generalized Integrate-and-Fire model featuring nonlinear firing threshold dynamics and conductance-based adaptation is introduced that outperforms state-of-the-art neuron models in predicting the spiking activity of neurons responding to a variety of in vivo-like fluctuating currents. Our model allows for efficient parameter extraction and can be analytically mapped to a Generalized Linear Model in which both the input filter--describing somatic integration--and the spike-history filter--accounting for spike-frequency adaptation--dynamically adapt to the input statistics, as experimentally observed. Overall, our results provide new insights on the computational role of different biophysical processes known to underlie adaptive coding in single neurons and support previous theoretical findings indicating that the nonlinear dynamics of the firing threshold due to Na+-channel inactivation regulate the sensitivity to rapid input fluctuations.

  20. Micropit: a new cell culturing approach for characterization of solitary astrocytes and small networks of these glial cells

    Directory of Open Access Journals (Sweden)

    William Lee

    2008-12-01

    Full Text Available Astrocytes play an important role in cell-cell signaling in the mammalian central nervous system. The ability of astrocytes to communicate with surrounding cells through gap-junctional coupling or signaling via the release of transmitters makes characterization of these cells difficult in vitro and even more so in vivo. To simplify the complexity of common in vitro systems, introduced by intercellular communication between astrocytes, we developed a novel cell culturing method, in which purified rat visual cortical astrocytes were grown in spatially defined cell-adhesion wells which we termed micropits. We showed that astrocytes cultured in micropit regions were viable and exhibited similar characteristics of Ca2+ dynamics and astrocytic marker expression to those of cells cultured in non-micropit regions. Examination of intracellular Ca2+ oscillations in solitary astrocytes cultured in micropits revealed less variable oscillations than those of non-micropit grouped astrocytes, which were in contact with their neighbors. Solitary cells in micropit regions can undergo ATP-mediated astrocyte-microglia signaling, demonstrating that this culturing method can also be used to investigate glial-glial interactions in a spatially well-defined microenvironment.

  1. Comparison of slow and fast neocortical neuron migration using a new in vitro model

    Directory of Open Access Journals (Sweden)

    Carney Laurel H

    2008-06-01

    Full Text Available Abstract Background Mutations, toxic insults and radiation exposure are known to slow or arrest the migration of cortical neurons, in most cases by unknown mechanisms. The movement of migrating neurons is saltatory, reflecting the intermittent movement of the nucleus (nucleokinesis within the confines of the plasma membrane. Each nucleokinetic movement is analogous to a step. Thus, average migration speed could be reduced by lowering step frequency and/or step distance. Results To assess the kinetic features of cortical neuron migration we developed a cell culture system that supports fiber-guided migration. In this system, the majority of fiber-apposed cells were neurons, expressed age-appropriate cortical-layer specific markers and migrated during a 30 min imaging period. Comparison of the slowest and fastest quartiles of cells revealed a 5-fold difference in average speed. The major determinant of average speed in slower cells (6–26 μm/hr was step frequency, while step distance was the critical determinant of average speed in faster cells (>26 μm/hr. Surprisingly, step distance was largely determined by the average duration of the step, rather than the speed of nucleokinesis during the step, which differed by only 1.3-fold between the slowest and fastest quartiles. Conclusion Saltatory event frequency and duration, not nucleokinetic speed, are the major determinants of average migration speed in healthy neurons. Alteration of either saltatory event frequency or duration should be considered along with nucleokinetic abnormalities as possible contributors to pathological conditions.

  2. Exploring the potential relationship between indoor air quality and the concentration of airborne culturable fungi: a combined experimental and neural network modeling study.

    Science.gov (United States)

    Liu, Zhijian; Cheng, Kewei; Li, Hao; Cao, Guoqing; Wu, Di; Shi, Yunjie

    2018-02-01

    Indoor airborne culturable fungi exposure has been closely linked to occupants' health. However, conventional measurement of indoor airborne fungal concentration is complicated and usually requires around one week for fungi incubation in laboratory. To provide an ultra-fast solution, here, for the first time, a knowledge-based machine learning model is developed with the inputs of indoor air quality data for estimating the concentration of indoor airborne culturable fungi. To construct a database for statistical analysis and model training, 249 data groups of air quality indicators (concentration of indoor airborne culturable fungi, indoor/outdoor PM 2.5 and PM 10 concentrations, indoor temperature, indoor relative humidity, and indoor CO 2 concentration) were measured from 85 residential buildings of Baoding (China) during the period of 2016.11.15-2017.03.15. Our results show that artificial neural network (ANN) with one hidden layer has good prediction performances, compared to a support vector machine (SVM). With the tolerance of ± 30%, the prediction accuracy of the ANN model with ten hidden nodes can at highest reach 83.33% in the testing set. Most importantly, we here provide a quick method for estimating the concentration of indoor airborne fungi that can be applied to real-time evaluation.

  3. Environmental factors shaping cultured free-living amoebae and their associated bacterial community within drinking water network.

    Science.gov (United States)

    Delafont, Vincent; Bouchon, Didier; Héchard, Yann; Moulin, Laurent

    2016-09-01

    Free-living amoebae (FLA) constitute an important part of eukaryotic populations colonising drinking water networks. However, little is known about the factors influencing their ecology in such environments. Because of their status as reservoir of potentially pathogenic bacteria, understanding environmental factors impacting FLA populations and their associated bacterial community is crucial. Through sampling of a large drinking water network, the diversity of cultivable FLA and their bacterial community were investigated by an amplicon sequencing approach, and their correlation with physicochemical parameters was studied. While FLA ubiquitously colonised the water network all year long, significant changes in population composition were observed. These changes were partially explained by several environmental parameters, namely water origin, temperature, pH and chlorine concentration. The characterisation of FLA associated bacterial community reflected a diverse but rather stable consortium composed of nearly 1400 OTUs. The definition of a core community highlighted the predominance of only few genera, majorly dominated by Pseudomonas and Stenotrophomonas. Co-occurrence analysis also showed significant patterns of FLA-bacteria association, and allowed uncovering potentially new FLA - bacteria interactions. From our knowledge, this study is the first that combines a large sampling scheme with high-throughput identification of FLA together with associated bacteria, along with their influencing environmental parameters. Our results demonstrate the importance of physicochemical parameters in the ecology of FLA and their bacterial community in water networks. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Evidence for a cerebral cortical thickness network anti-correlated with amygdalar volume in healthy youths: implications for the neural substrates of emotion regulation.

    Science.gov (United States)

    Albaugh, Matthew D; Ducharme, Simon; Collins, D Louis; Botteron, Kelly N; Althoff, Robert R; Evans, Alan C; Karama, Sherif; Hudziak, James J

    2013-05-01

    Recent functional connectivity studies have demonstrated that, in resting humans, activity in a dorsally-situated neocortical network is inversely associated with activity in the amygdalae. Similarly, in human neuroimaging studies, aspects of emotion regulation have been associated with increased activity in dorsolateral, dorsomedial, orbital and ventromedial prefrontal regions, as well as concomitant decreases in amygdalar activity. These findings indicate the presence of two countervailing systems in the human brain that are reciprocally related: a dorsally-situated cognitive control network, and a ventrally-situated limbic network. We investigated the extent to which this functional reciprocity between limbic and dorsal neocortical regions is recapitulated from a purely structural standpoint. Specifically, we hypothesized that amygdalar volume would be related to cerebral cortical thickness in cortical regions implicated in aspects of emotion regulation. In 297 typically developing youths (162 females, 135 males; 572 MRIs), the relationship between cortical thickness and amygdalar volume was characterized. Amygdalar volume was found to be inversely associated with thickness in bilateral dorsolateral and dorsomedial prefrontal, inferior parietal, as well as bilateral orbital and ventromedial prefrontal cortices. Our findings are in line with previous work demonstrating that a predominantly dorsally-centered neocortical network is reciprocally related to core limbic structures such as the amygdalae. Future research may benefit from investigating the extent to which such cortical-limbic morphometric relations are qualified by the presence of mood and anxiety psychopathology. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Cited2 Regulates Neocortical Layer II/III Generation and Somatosensory Callosal Projection Neuron Development and Connectivity.

    Science.gov (United States)

    Fame, Ryann M; MacDonald, Jessica L; Dunwoodie, Sally L; Takahashi, Emi; Macklis, Jeffrey D

    2016-06-15

    The neocortex contains hundreds to thousands of distinct subtypes of precisely connected neurons, allowing it to perform remarkably complex tasks of high-level cognition. Callosal projection neurons (CPN) connect the cerebral hemispheres via the corpus callosum, integrating cortical information and playing key roles in associative cognition. CPN are a strikingly diverse set of neuronal subpopulations, and development of this diversity requires precise control by a complex, interactive set of molecular effectors. We have found that the transcriptional coregulator Cited2 regulates and refines two stages of CPN development. Cited2 is expressed broadly by progenitors in the embryonic day 15.5 subventricular zone, during the peak of superficial layer CPN birth, with a progressive postmitotic refinement in expression, becoming restricted to CPN of the somatosensory cortex postnatally. We generated progenitor-stage and postmitotic forebrain-specific Cited2 conditional knock-out mice, using the Emx1-Cre and NEX-Cre mouse lines, respectively. We demonstrate that Cited2 functions in progenitors, but is not necessary postmitotically, to regulate both (1) broad generation of layer II/III CPN and (2) acquisition of precise area-specific molecular identity and axonal/dendritic connectivity of somatosensory CPN. This novel CPN subtype-specific and area-specific control from progenitor action of Cited2 adds yet another layer of complexity to the multistage developmental regulation of neocortical development. This study identifies Cited2 as a novel subtype-specific and area-specific control over development of distinct subpopulations within the broad population of callosal projection neurons (CPN), whose axons connect the two cerebral hemispheres via the corpus callosum (CC). Currently, how the remarkable diversity of CPN subtypes is specified, and how they differentiate to form highly precise and specific circuits, are largely unknown. We found that Cited2 functions within

  6. Evidence-based practice center network and health technology assessment in the United States: bridging the cultural gap.

    Science.gov (United States)

    Sarría-Santamera, Antonio; Matchar, David B; Westermann-Clark, Emma V; Patwardhan, Meenal B

    2006-01-01

    The purpose of this study was to identify the Evidence-Based Practice Center (EPC) network participants' perceptions of the characteristics of the EPC process and the relationship of the process to the success of EPC reports. Semistructured interviews were conducted with the three groups involved in the EPC: EPC staff, Agency for Healthcare Research and Quality (AHRQ) staff, and representatives of partner organizations. The analysis of the coded transcripts revealed three related major themes, which form the conceptual basis for the interpretation presented here: the definition of a successful report, the determinants of a successful report, and the role of AHRQ in the process. A successful report is a report that is used. The ultimate success of the core health technology assessment objective, moving from research to policy, depends on balancing two values: excellence and relevance. Our findings are consistent with the "two communities thesis," which postulates the existence of two camps that confer different values to excellence and relevance, with resulting tension. A promising model for approaching this tension is integration or collaboration, which requires linking researchers and policy makers, promoting productive dialogues about the formulation and timing of analysis, and early consideration of how the resulting analysis will be used. This effort suggests that actively blurring the frontiers between these two groups will enhance their interaction. Furthermore, enhancing the role of the AHRQ as scientific broker will maximize the potential of the EPC network.

  7. Political Culture, Indigenous Participation, and Communication Networks during the Colonial Crisis. The Case of the Peruvian Viceroyalty, 1809-1914

    Directory of Open Access Journals (Sweden)

    Luis Miguel Glave

    2008-07-01

    Full Text Available When the juntista movement bursted out in the Viceroyalty of Peru, the society had already been living in constant agitation for several decades. The oligarchical aristocracies rearranged after the 1780 crisis kept up an open struggle for power. Racial, cultural, and political divisions became more visible. Among the Indians, defeat had left a void that was being filled up by local chieftainships  and a collective  sensibility  returning to  myths and building an ongoing memory  of resistance. The Church and local authorities came to fulfill the role of guardians of collective rights,  and an almost  underwater current of legal and political resistance could be felt in the towns  and villas of every region. This  work  seeks these  new  actors,  rescued  from  oblivion, for they offer a new face for the rebellious  towns  and allow a bet­ ter understanding of the cultural  and political processes  in the Americas.

  8. Epidemic microclusters of blood-culture proven sepsis in very-low-birth weight infants: experience of the German Neonatal Network.

    Science.gov (United States)

    Härtel, Christoph; Faust, Kirstin; Avenarius, Stefan; Bohnhorst, Bettina; Emeis, Michael; Gebauer, Corinna; Groneck, Peter; Heitmann, Friedhelm; Hoehn, Thomas; Hubert, Mechthild; Kribs, Angela; Küster, Helmut; Laux, Reinhard; Mögel, Michael; Müller, Dirk; Olbertz, Dirk; Roll, Claudia; Siegel, Jens; Stein, Anja; Vochem, Matthias; Weller, Ursula; von der Wense, Axel; Wieg, Christian; Wintgens, Jürgen; Hemmelmann, Claudia; Simon, Arne; Herting, Egbert; Göpel, Wolfgang

    2012-01-01

    We evaluated blood culture-proven sepsis episodes occurring in microclusters in very-low-birth-weight infants born in the German Neonatal Network (GNN) during 2009-2010. Thirty-seven centers participated in GNN; 23 centers enrolled ≥50 VLBW infants in the study period. Data quality was approved by on-site monitoring. Microclusters of sepsis were defined as occurrence of at least two blood-culture proven sepsis events in different patients of one center within 3 months with the same bacterial species. For microcluster analysis, we selected sepsis episodes with typically cross-transmitted bacteria of high clinical significance including gram-negative rods and Enterococcus spp. In our cohort, 12/2110 (0.6%) infants were documented with an early-onset sepsis and 235 late-onset sepsis episodes (≥72 h of age) occurred in 203/2110 (9.6%) VLBW infants. In 182/235 (77.4%) late-onset sepsis episodes gram-positive bacteria were documented, while coagulase negative staphylococci were found to be the most predominant pathogens (48.5%, 95%CI: 42.01-55.01). Candida spp. and gram-negative bacilli caused 10/235 (4.3%, 95%CI: 1.68% -6.83%) and 43/235 (18.5%) late-onset sepsis episodes, respectively. Eleven microclusters of blood-culture proven sepsis were detected in 7 hospitals involving a total 26 infants. 16/26 cluster patients suffered from Klebsiella spp. sepsis. The median time interval between the first patient's Klebsiella spp. sepsis and cluster cases was 14.1 days (interquartile range: 1-27 days). First patients in the cluster, their linked cases and sporadic sepsis events did not show significant differences in short term outcome parameters. Microclusters of infection are an important phenomenon for late-onset sepsis. Most gram-negative cluster infections occur within 30 days after the first patient was diagnosed and Klebsiella spp. play a major role. It is essential to monitor epidemic microclusters of sepsis in surveillance networks to adapt clinical practice

  9. Effect of Prenatal Protein Malnutrition on Long-Term Potentiation and BDNF Protein Expression in the Rat Entorhinal Cortex after Neocortical and Hippocampal Tetanization

    Directory of Open Access Journals (Sweden)

    Alejandro Hernández

    2008-01-01

    Full Text Available Reduction of the protein content from 25 to 8% casein in the diet of pregnant rats results in impaired neocortical long-term potentiation (LTP of the offspring together with lower visuospatial memory performance. The present study was aimed to investigate whether this type of maternal malnutrition could result in modification of plastic capabilities of the entorhinal cortex (EC in the adult progeny. Unlike normal eutrophic controls, 55–60-day-old prenatally malnourished rats were unable to develop LTP in the medial EC to tetanizing stimulation delivered to either the ipsilateral occipital cortex or the CA1 hippocampal region. Tetanizing stimulation of CA1 also failed to increase the concentration of brain-derived neurotrophic factor (BDNF in the EC of malnourished rats. Impaired capacity of the EC of prenatally malnourished rats to develop LTP and to increase BDNF levels during adulthood may be an important factor contributing to deficits in learning performance having adult prenatally malnourished animals.

  10. Effect of prenatal protein malnutrition on long-term potentiation and BDNF protein expression in the rat entorhinal cortex after neocortical and hippocampal tetanization.

    Science.gov (United States)

    Hernández, Alejandro; Burgos, Héctor; Mondaca, Mauricio; Barra, Rafael; Núñez, Héctor; Pérez, Hernán; Soto-Moyano, Rubén; Sierralta, Walter; Fernández, Victor; Olivares, Ricardo; Valladares, Luis

    2008-01-01

    Reduction of the protein content from 25 to 8% casein in the diet of pregnant rats results in impaired neocortical long-term potentiation (LTP) of the offspring together with lower visuospatial memory performance. The present study was aimed to investigate whether this type of maternal malnutrition could result in modification of plastic capabilities of the entorhinal cortex (EC) in the adult progeny. Unlike normal eutrophic controls, 55-60-day-old prenatally malnourished rats were unable to develop LTP in the medial EC to tetanizing stimulation delivered to either the ipsilateral occipital cortex or the CA1 hippocampal region. Tetanizing stimulation of CA1 also failed to increase the concentration of brain-derived neurotrophic factor (BDNF) in the EC of malnourished rats. Impaired capacity of the EC of prenatally malnourished rats to develop LTP and to increase BDNF levels during adulthood may be an important factor contributing to deficits in learning performance having adult prenatally malnourished animals.

  11. Neocortical concentrations of neuropeptides in senile dementia of the Alzheimer and Lewy body type: comparison with Parkinson's disease and severity correlations.

    Science.gov (United States)

    Leake, A; Perry, E K; Perry, R H; Jabeen, S; Fairbairn, A F; McKeith, I G; Ferrier, I N

    1991-02-15

    Corticotropin releasing hormone (CRH), somatostatin (SRIF), and arginine vasopressin (AVP) concentrations were estimated using radioimmunoassay in the temporal and occipital cortices in postmortem brain from patients clinically and neuropathologically diagnosed as senile dementia of the Lewy body type (SDLT), senile dementia of the Alzheimer type (SDAT), and Parkinson's disease (PD) and from neurologically normal controls. The concentration of temporal and occipital neocortical CRH was diminished in both SDAT and SDLT compared to control values, whereas SRIF was reduced only in temporal cortex in both these conditions. In contrast, the concentrations of both CRH and SRIF were unaltered in PD. The concentrations of AVP in SDLT, SDAT, and PD were similar to those found in the control groups. The decrement in SRIF, but not CRH, was found to be correlated with some indices of severity of illness in SDAT; a similar but nonsignificant trend for SRIF was observed in SDLT.

  12. The Outwardly Rectifying Current of Layer 5 Neocortical Neurons that was Originally Identified as "Non-Specific Cationic" Is Essentially a Potassium Current.

    Directory of Open Access Journals (Sweden)

    Omer Revah

    Full Text Available In whole-cell patch clamp recordings from layer 5 neocortical neurons, blockade of voltage gated sodium and calcium channels leaves a cesium current that is outward rectifying. This current was originally identified as a "non-specific cationic current", and subsequently it was hypothesized that it is mediated by TRP channels. In order to test this hypothesis, we used fluorescence imaging of intracellular sodium and calcium indicators, and found no evidence to suggest that it is associated with influx of either of these ions to the cell body or dendrites. Moreover, the current is still prominent in neurons from TRPC1-/- and TRPC5-/- mice. The effects on the current of various blocking agents, and especially its sensitivity to intracellular tetraethylammonium, suggest that it is not a non-specific cationic current, but rather that it is generated by cesium-permeable delayed rectifier potassium channels.

  13. The Role of Cultural and Identity Differences in Self-expression of Iranian Users of Social Networking Sites; A Case Study of Students of Tehran University, Amirkabir University, and Sharif University of Technology

    Directory of Open Access Journals (Sweden)

    H. Molaei

    2017-12-01

    Full Text Available Social media with their features such as interactivity, participatory, and user-generated content have provided a great opportunity for self-expression of the users. However, cultural differences affect the extent and modality of users’ self-expression. This study aims to investigate the modality of self-expression of Iranian users of the social networking sites. In doing so, an online survey was conducted among the students of three Iran universities: University of Tehran, Amirkabir University of Technology, and Sharif University of Technology. A total of 371 students participated in the study. Having conducted quantitative analysis, the study results showed that women and ethnic minorities are more inclined to support their cultural differences compared to men and ethnic majority group. Supporting cultural differences was observed more among Shia religious majority group. Religious minorities expressed less tendency to create content in social networking sites and as a result support their religious identity.

  14. The DISC (Diabetes in Social Context) Study-evaluation of a culturally sensitive social network intervention for diabetic patients in lower socioeconomic groups: a study protocol.

    Science.gov (United States)

    Vissenberg, Charlotte; Nierkens, Vera; Uitewaal, Paul J M; Geraci, Diana; Middelkoop, Barend J C; Nijpels, Giel; Stronks, Karien

    2012-03-19

    Compared to those in higher socioeconomic groups, diabetic patients in lower socioeconomic groups have less favourable metabolic control and experience more diabetes-related complications. They encounter specific barriers that hinder optimal diabetes self-management, including a lack of social support and other psychosocial mechanisms in their immediate social environments. Powerful Together with Diabetes is a culturally sensitive social network intervention specifically targeted to ethnic Dutch, Moroccan, Turkish, and Surinamese diabetic patients in lower socioeconomic groups. For ten months, patients will participate in peer support groups in which they will share experiences, support each other in maintaining healthy lifestyles, and learn skills to resist social pressure. At the same time, their significant others will also receive an intervention, aimed at maximizing support for and minimizing the negative social influences on diabetes self-management. This study aims to test the effectiveness of Powerful Together with Diabetes. We will use a quasi-experimental design with an intervention group (Group 1) and two comparison groups (Groups 2 and 3), N = 128 in each group. Group 1 will receive Powerful Together with Diabetes. Group 2 will receive Know your Sugar, a six-week group intervention that does not focus on the participants' social environments. Group 3 receives standard care only. Participants in Groups 1 and 2 will be interviewed and physically examined at baseline, 3, 10, and 16 months. We will compare their haemoglobin A1C levels with the haemoglobin A1C levels of Group 3. Main outcome measures are haemoglobin A1C, diabetes-related quality of life, diabetes self-management, health-related, and intermediate outcome measures. We will conduct a process evaluation and a qualitative study to gain more insights into the intervention fidelity, feasibility, and changes in the psychosocial mechanism in the participants' immediate social environments. With this

  15. The DISC (Diabetes in Social Context Study-evaluation of a culturally sensitive social network intervention for diabetic patients in lower socioeconomic groups: a study protocol

    Directory of Open Access Journals (Sweden)

    Vissenberg Charlotte

    2012-03-01

    Full Text Available Abstract Background Compared to those in higher socioeconomic groups, diabetic patients in lower socioeconomic groups have less favourable metabolic control and experience more diabetes-related complications. They encounter specific barriers that hinder optimal diabetes self-management, including a lack of social support and other psychosocial mechanisms in their immediate social environments. Powerful Together with Diabetes is a culturally sensitive social network intervention specifically targeted to ethnic Dutch, Moroccan, Turkish, and Surinamese diabetic patients in lower socioeconomic groups. For ten months, patients will participate in peer support groups in which they will share experiences, support each other in maintaining healthy lifestyles, and learn skills to resist social pressure. At the same time, their significant others will also receive an intervention, aimed at maximizing support for and minimizing the negative social influences on diabetes self-management. This study aims to test the effectiveness of Powerful Together with Diabetes. Methods/Design We will use a quasi-experimental design with an intervention group (Group 1 and two comparison groups (Groups 2 and 3, N = 128 in each group. Group 1 will receive Powerful Together with Diabetes. Group 2 will receive Know your Sugar, a six-week group intervention that does not focus on the participants' social environments. Group 3 receives standard care only. Participants in Groups 1 and 2 will be interviewed and physically examined at baseline, 3, 10, and 16 months. We will compare their haemoglobin A1C levels with the haemoglobin A1C levels of Group 3. Main outcome measures are haemoglobin A1C, diabetes-related quality of life, diabetes self-management, health-related, and intermediate outcome measures. We will conduct a process evaluation and a qualitative study to gain more insights into the intervention fidelity, feasibility, and changes in the psychosocial mechanism in the

  16. Pintadas network

    OpenAIRE

    Cruz, Maria do Carmo Meirelles T.

    2006-01-01

    The Pintadas Network has been organized in Pintadas, a small municipality (11.254 inhabitants) in Bahia, located in the semi-arid region. It has been composed by civil society organizacions (social, productive, cultural and religious organizations and a credit cooperative), with support from the local town hall and from national and international institutions. The Network is a space for articulation, which intends to formulate, execute, follow-up, inspect and evaluate the municipal public pol...

  17. Decreased graft survival in liver transplant recipients of donors with positive blood cultures: a review of the United Network for Organ Sharing dataset.

    Science.gov (United States)

    Huaman, Moises A; Vilchez, Valery; Mei, Xiaonan; Shah, Malay B; Daily, Michael F; Berger, Jonathan; Gedaly, Roberto

    2017-06-01

    Liver transplantation using blood culture positive donors (BCPD) has allowed a significant expansion of the donor pool. We aimed to characterize BCPD and assess the outcomes of BCPD liver transplant recipients. We retrieved data from the United Network for Organ Sharing (UNOS) registry on all adults who underwent primary, single-organ deceased-donor liver transplantation in the USA between 2008 and 2013. Patients were classified into two cohorts: the BCPD cohort and the non-BCPD cohort. One-year graft and patient survival were compared between cohorts using Kaplan-Meier estimates and Cox models. A total of 28 961 patients were included. There were 2316 (8.0%) recipients of BCPD. BCPD were more likely to be older, female, black, diabetic, hypertensive, and obese compared to non-BCPD. Graft survival was significantly lower in BCPD recipients compared to non-BCPD recipients (Kaplan-Meier, 0.85 vs. 0.87; P = 0.009). Results remained significant in propensity-matched analysis (P = 0.038). BCPD was independently associated with decreased graft survival (adjusted HR; 1.10, 95% CI 1.01-1.20; P = 0.04). There were no significant differences in patient survival between study groups. BCPD was associated with decreased graft survival in liver transplant recipients. Studies are needed to identify subgroups of BCPD with the highest risk of graft failure and characterize the underlying pathogenic mechanisms. © 2016 Steunstichting ESOT.

  18. Corrigendum to “Long-term valproic acid exposure increases the number of neocortical neurons in the developing rat brain" [Neurosci.Lett. 580 (2014) 12–16] A possible new animal model of autism

    DEFF Research Database (Denmark)

    Sabers, Anne; Bertelsen, Freja C B; Scheel-Krüger, Jørgen

    2015-01-01

    The aim of this study was to test the hypothesis that long-term fetal valproic acid (VPA) exposure at doses relevant to the human clinic interferes with normal brain development. Pregnant rats were given intraperitoneal injections of VPA (20 mg/kg or 100 mg/kg) continuously during the last 9......–12 days of pregnancy and during the lactation period until sacrifice on the 23rd postnatal day. Total number of neocortical neurons was estimated using the optical fraction at or and frontal cortical thicknesses were sampled in VPA exposed pups compared with an unexposed control group. We found that pups....... Pups exposed to 100 mg/kg, but not to 20 mg/kg VPA displayed a significant (p brain development by disturbing neocortical organization...

  19. Electro-acupuncture at different acupoints modulating the relative specific brain functional network

    Science.gov (United States)

    Fang, Jiliang; Wang, Xiaoling; Wang, Yin; Liu, Hesheng; Hong, Yang; Liu, Jun; Zhou, Kehua; Wang, Lei; Xue, Chao; Song, Ming; Liu, Baoyan; Zhu, Bing

    2010-11-01

    Objective: The specific brain effects of acupoint are important scientific concern in acupuncture. However, previous acupuncture fMRI studies focused on acupoints in muscle layer on the limb. Therefore, researches on acupoints within connective tissue at trunk are warranted. Material and Methods: Brain effects of acupuncture on abdomen at acupoints Guanyuan (CV4) and Zhongwan (CV12) were tested using fMRI on 21 healthy volunteers. The data acquisition was performed at resting state, during needle retention, electroacupuncture (EA) and post-EA resting state. Needling sensations were rated after every electroacupuncture (EA) procedure. The needling sensations and the brain functional activity and connectivity were compared between CV4 and CV12 using SPSS, SPM2 and the local and remote connectivity maps. Results and conclusion: EA at CV4 and CV12 induced apparent deactivation effects in the limbic-paralimbic-neocortical network. The default mode of the brain was modified by needle retention and EA, respectively. The functional brain network was significantly changed post EA. However, the minor differences existed between these two acupoints. The results demonstrated similarity between functional brain network mode of acupuncture modulation and functional circuits of emotional and cognitive regulation. Acupuncture may produce analgesia, anti-anxiety and anti-depression via the limbic-paralimbic-neocortical network (LPNN).

  20. Cultural neurolinguistics.

    Science.gov (United States)

    Chen, Chuansheng; Xue, Gui; Mei, Leilei; Chen, Chunhui; Dong, Qi

    2009-01-01

    As the only species that evolved to possess a language faculty, humans have been surprisingly generative in creating a diverse array of language systems. These systems vary in phonology, morphology, syntax, and written forms. Before the advent of modern brain-imaging techniques, little was known about how differences across languages are reflected in the brain. This chapter aims to provide an overview of an emerging area of research - cultural neurolinguistics - that examines systematic cross-cultural/crosslinguistic variations in the neural networks of languages. We first briefly describe general brain networks for written and spoken languages. We then discuss language-specific brain regions by highlighting differences in neural bases of different scripts (logographic vs. alphabetic scripts), orthographies (transparent vs. nontransparent orthographies), and tonality (tonal vs. atonal languages). We also discuss neural basis of second language and the role of native language experience in second-language acquisition. In the last section, we outline a general model that integrates culture and neural bases of language and discuss future directions of research in this area.

  1. Episodic memory in aspects of large-scale brain networks

    Science.gov (United States)

    Jeong, Woorim; Chung, Chun Kee; Kim, June Sic

    2015-01-01

    Understanding human episodic memory in aspects of large-scale brain networks has become one of the central themes in neuroscience over the last decade. Traditionally, episodic memory was regarded as mostly relying on medial temporal lobe (MTL) structures. However, recent studies have suggested involvement of more widely distributed cortical network and the importance of its interactive roles in the memory process. Both direct and indirect neuro-modulations of the memory network have been tried in experimental treatments of memory disorders. In this review, we focus on the functional organization of the MTL and other neocortical areas in episodic memory. Task-related neuroimaging studies together with lesion studies suggested that specific sub-regions of the MTL are responsible for specific components of memory. However, recent studies have emphasized that connectivity within MTL structures and even their network dynamics with other cortical areas are essential in the memory process. Resting-state functional network studies also have revealed that memory function is subserved by not only the MTL system but also a distributed network, particularly the default-mode network (DMN). Furthermore, researchers have begun to investigate memory networks throughout the entire brain not restricted to the specific resting-state network (RSN). Altered patterns of functional connectivity (FC) among distributed brain regions were observed in patients with memory impairments. Recently, studies have shown that brain stimulation may impact memory through modulating functional networks, carrying future implications of a novel interventional therapy for memory impairment. PMID:26321939

  2. Episodic memory in aspects of large-scale brain networks

    Directory of Open Access Journals (Sweden)

    Woorim eJeong

    2015-08-01

    Full Text Available Understanding human episodic memory in aspects of large-scale brain networks has become one of the central themes in neuroscience over the last decade. Traditionally, episodic memory was regarded as mostly relying on medial temporal lobe (MTL structures. However, recent studies have suggested involvement of more widely distributed cortical network and the importance of its interactive roles in the memory process. Both direct and indirect neuro-modulations of the memory network have been tried in experimental treatments of memory disorders. In this review, we focus on the functional organization of the MTL and other neocortical areas in episodic memory. Task-related neuroimaging studies together with lesion studies suggested that specific sub-regions of the MTL are responsible for specific components of memory. However, recent studies have emphasized that connectivity within MTL structures and even their network dynamics with other cortical areas are essential in the memory process. Resting-state functional network studies also have revealed that memory function is subserved by not only the MTL system but also a distributed network, particularly the default-mode network. Furthermore, researchers have begun to investigate memory networks throughout the entire brain not restricted to the specific resting-state network. Altered patterns of functional connectivity among distributed brain regions were observed in patients with memory impairments. Recently, studies have shown that brain stimulation may impact memory through modulating functional networks, carrying future implications of a novel interventional therapy for memory impairment.

  3. Global Networking.

    Science.gov (United States)

    Lynch, Clifford

    1997-01-01

    Discusses the state of the Internet. Highlights include the magnitude of the infrastructure, costs, its increasing pace, constraints in international links, provision of network capacity to homes and small businesses, cable television modems, political and cultural problems, the digital library concept, search engines, the failure of personal…

  4. The Role of Cultural and Identity Differences in Self-expression of Iranian Users of Social Networking Sites; A Case Study of Students of Tehran University, Amirkabir University, and Sharif University of Technology

    OpenAIRE

    H. Molaei; Z. Majdizadeh

    2017-01-01

    Social media with their features such as interactivity, participatory, and user-generated content have provided a great opportunity for self-expression of the users. However, cultural differences affect the extent and modality of users’ self-expression. This study aims to investigate the modality of self-expression of Iranian users of the social networking sites. In doing so, an online survey was conducted among the students of three Iran universities: University of Tehran, Amirkabir Universi...

  5. Diluted connectivity in pattern association networks facilitates the recall of information from the hippocampus to the neocortex.

    Science.gov (United States)

    Rolls, Edmund T

    2015-01-01

    The recall of information stored in the hippocampus involves a series of corticocortical backprojections via the entorhinal cortex, parahippocampal gyrus, and one or more neocortical stages. Each stage is considered to be a pattern association network, with the retrieval cue at each stage the firing of neurons in the previous stage. The leading factor that determines the capacity of this multistage pattern association backprojection pathway is the number of connections onto any one neuron, which provides a quantitative basis for why there are as many backprojections between adjacent stages in the hierarchy as forward projections. The issue arises of why this multistage backprojection system uses diluted connectivity. One reason is that a multistage backprojection system with expansion of neuron numbers at each stage enables the hippocampus to address during recall the very large numbers of neocortical neurons, which would otherwise require hippocampal neurons to make very large numbers of synapses if they were directly onto neocortical neurons. The second reason is that as shown here, diluted connectivity in the backprojection pathways reduces the probability of more than one connection onto a receiving neuron in the backprojecting pathways, which otherwise reduces the capacity of the system, that is the number of memories that can be recalled from the hippocampus to the neocortex. For similar reasons, diluted connectivity is advantageous in pattern association networks in other brain systems such as the orbitofrontal cortex and amygdala; for related reasons, in autoassociation networks in, for example, the hippocampal CA3 and the neocortex; and for the different reason that diluted connectivity facilitates the operation of competitive networks in forward-connected cortical systems. © 2015 Elsevier B.V. All rights reserved.

  6. Network Culture, Performance & Corporate Responsibility

    OpenAIRE

    Silvio M. Brondoni

    2003-01-01

    The growth and sustainability of free market economies highlights the need to define rules more suited to the current condition of market globalisation and also encourages firms to adopt more transparent and accountable corporate responsibility (and corporate social responsibility, namely the relationship between the company, environment and social setting). From a managerial perspective, corporate responsibility is linked to ensure the lasting pursuit of the company mission, seeking increasi...

  7. Imaging Cajal's neuronal avalanche: how wide-field optical imaging of the point-spread advanced the understanding of neocortical structure-function relationship.

    Science.gov (United States)

    Frostig, Ron D; Chen-Bee, Cynthia H; Johnson, Brett A; Jacobs, Nathan S

    2017-07-01

    This review brings together a collection of studies that specifically use wide-field high-resolution mesoscopic level imaging techniques (intrinsic signal optical imaging; voltage-sensitive dye optical imaging) to image the cortical point spread (PS): the total spread of cortical activation comprising a large neuronal ensemble evoked by spatially restricted (point) stimulation of the sensory periphery (e.g., whisker, pure tone, point visual stimulation). The collective imaging findings, combined with supporting anatomical and electrophysiological findings, revealed some key aspects about the PS including its very large (radius of several mm) and relatively symmetrical spatial extent capable of crossing cytoarchitectural borders and trespassing into other cortical areas; its relationship with underlying evoked subthreshold activity and underlying anatomical system of long-range horizontal projections within gray matter, both also crossing borders; its contextual modulation and plasticity; the ability of its relative spatiotemporal profile to remain invariant to major changes in stimulation parameters; its potential role as a building block for integrative cortical activity; and its ubiquitous presence across various cortical areas and across mammalian species. Together, these findings advance our understanding about the neocortex at the mesoscopic level by underscoring that the cortical PS constitutes a fundamental motif of neocortical structure-function relationship.

  8. Successful declarative memory formation is associated with ongoing activity during encoding in a distributed neocortical network related to working memory: a magnetoencephalography study.

    NARCIS (Netherlands)

    Takashima, A.; Jensen, O.; Oostenveld, R.; Maris, E.G.G.; Coevering, M. van de; Fernandez, G.S.E.

    2006-01-01

    The aim of the present study was to investigate the spatio-temporal characteristics of the neural correlates of declarative memory formation as assessed by the subsequent memory effect, i.e. the difference in encoding activity between subsequently remembered and subsequently forgotten items.

  9. Successful declarative memory formation is associated with ongoing activity during encoding in a distributed neocortical network related to working memory: A magnetoencephalography study

    NARCIS (Netherlands)

    Takashima, A.; Jensen, O.; Oostenveld, R.; Maris, E.G.G.; Coevering, M. van de; Fernandez, G.S.E.

    2006-01-01

    The aim of the present study was to investigate the spatio-temporal characteristics of the neural correlates of declarative memory formation as assessed by the subsequent memory effect, i.e. the difference in encoding activity between subsequently remembered and subsequently forgotten items.

  10. Small Worlds and Cultural Polarization

    NARCIS (Netherlands)

    Flache, Andreas; Macy, Michael W.

    2011-01-01

    Building on Granovetter's theory of the "strength of weak ties,'' research on "small-world'' networks suggests that bridges between clusters in a social network (long-range ties) promote cultural diffusion, homogeneity, and integration. We show that this macro-level implication of network structure

  11. Infection with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance--Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2012-2015.

    Science.gov (United States)

    Huang, Jennifer Y; Henao, Olga L; Griffin, Patricia M; Vugia, Duc J; Cronquist, Alicia B; Hurd, Sharon; Tobin-D'Angelo, Melissa; Ryan, Patricia; Smith, Kirk; Lathrop, Sarah; Zansky, Shelley; Cieslak, Paul R; Dunn, John; Holt, Kristin G; Wolpert, Beverly J; Patrick, Mary E

    2016-04-15

    To evaluate progress toward prevention of enteric and foodborne illnesses in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) monitors the incidence of laboratory-confirmed infections caused by nine pathogens transmitted commonly through food in 10 U.S. sites. This report summarizes preliminary 2015 data and describes trends since 2012. In 2015, FoodNet reported 20,107 confirmed cases (defined as culture-confirmed bacterial infections and laboratory-confirmed parasitic infections), 4,531 hospitalizations, and 77 deaths. FoodNet also received reports of 3,112 positive culture-independent diagnostic tests (CIDTs) without culture-confirmation, a number that has markedly increased since 2012. Diagnostic testing practices for enteric pathogens are rapidly moving away from culture-based methods. The continued shift from culture-based methods to CIDTs that do not produce the isolates needed to distinguish between strains and subtypes affects the interpretation of public health surveillance data and ability to monitor progress toward prevention efforts. Expanded case definitions and strategies for obtaining bacterial isolates are crucial during this transition period.

  12. Intergenerational Relationships in Cross-Cultural Comparison: How Social Networks Frame Intergenerational Relations between Mothers and Grandmothers in Japan, Korea, China, Indonesia, Israel, Germany, and Turkey

    Science.gov (United States)

    Nauck, Bernhard; Suckow, Jana

    2006-01-01

    The article explores the relevance of intergenerational relationships within the overall network of young mothers and grandmothers in seven societies: Japan, Korea, China, Indonesia, Turkey, Israel, and Germany. The empirical base is 2,945 named network members in 249 pairs of interviews of grandmothers and their daughters from a cross-cultural…

  13. The true ‘EURESCO’? The Council of Europe,transnational networking and the emergence of European Community cultural policies, 1970–90

    NARCIS (Netherlands)

    Calligaro, Oriane; Patel, Kiran Klaus

    2017-01-01

    The roots of EU action in the field of culture lie in the 1970s. At the time, the Council of Europe (CoE), the United Nations Education, Scientific and Cultural Organization (UNESCO) and other organizations were already established players in the field. This article analyses the incremental and

  14. Mapping to mouse chromosome 3 of the gene encoding latexin (Lxn) expressed in neocortical neurons in a region-specific manner

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Ming-hao; Uratani, Yoshihiko; Arimatsu, Yasuyoshi [Mitsubishi Kasei Institute of Life Sciences, Tokyo (Japan)

    1997-02-01

    Latexin was first found as a 29-kDa antigen expressed in a subset of neurons in infragranular layers of lateral, but not dorsal, neocortical areas in the rat using a monoclonal antibody PC3.1. It was found that the vast majority of latexin-expressing neurons in both layers V and VI within the lateral neocortex were generated concurrently at Embryonic Day 15, demonstrating a strict correlation between the molecular identity of neurons and the time of their generation. Since neurons expressing latexin are located in the restricted part of the neocortex, latexin has been used as a useful molecular marker to elucidate the mechanism underlying cortical regional specification. The latexin cDNA isolated from a cDNA library of the rat cerebral cortex encodes a protein composed of 223-amino-acid residues containing two potential Ca{sup 2+}/calmodulin-dependent protein kinase sites and one cGMP-dependent protein kinase phosphorylation site. The absence of any signal peptide or potential transmembrane domain is consistent with the apparent cytosolic localization of latexin in the rat brain. The transcripts of latexin were expressed in not only neutral but also nonneural tissues (e.g., lung, spleen, kidney, heart, and digestive tracts). Recently, it has been demonstrated that latexin purified from the rat brain has inhibitory activity against carboxypeptidase A1, carboxypeptidase A2, and mast cell carboxypeptidase A, with less carboxypeptidase B-inhibiting activity. The amino acid sequence deduced from the rat latexin cDNA has no strict homology to any sequences so far known. Genomic Southern blot analysis using a cDNA probe of rat latexin suggested that the gene encoding latexin in the rat has homologues in other mammalian species and in the chicken, but not in the nematode, fly, or frog. 9 refs., 1 fig.

  15. Citizenship and cultural diversity in agenda of cultural policies

    Directory of Open Access Journals (Sweden)

    Patricia Silva Dorneles

    2016-01-01

    Full Text Available This is a discussion paper which aims to contribute to the systematization of studies, concepts and practices on cultural policies which have been developed in previous years in Brazil and are orienting cultural actions and public programs in the country, also influencing the Occupational Therapy. Citizenship and Cultural Diversity are concepts under construction and are part of the of the agenda of cultural policies and as well as the reflections and practices of various occupational therapists who are acting in a constant dialogue with the cultural area by means of the formation in cultural management, cultural mapping, programs and grant projects aimed to promote inventive identities, traditional communities, native populations, urban mobility, and cultural networks and exchange initiatives, among others. The article presents the process of this conceptual construction and the constitution of experiences aiming the democratization of the culture in the history of Brazilian cultural public policies, over which are being discussed approach paths and possibilities for Occupational Therapy.

  16. Spatial patterns of atrophy, hypometabolism, and amyloid deposition in Alzheimer's disease correspond to dissociable functional brain networks.

    Science.gov (United States)

    Grothe, Michel J; Teipel, Stefan J

    2016-01-01

    Recent neuroimaging studies of Alzheimer's disease (AD) have emphasized topographical similarities between AD-related brain changes and a prominent cortical association network called the default-mode network (DMN). However, the specificity of distinct imaging abnormalities for the DMN compared to other intrinsic connectivity networks (ICNs) of the limbic and heteromodal association cortex has not yet been examined systematically. We assessed regional amyloid load using AV45-PET, neuronal metabolism using FDG-PET, and gray matter volume using structural MRI in 473 participants from the Alzheimer's Disease Neuroimaging Initiative, including preclinical, predementia, and clinically manifest AD stages. Complementary region-of-interest and voxel-based analyses were used to assess disease stage- and modality-specific changes within seven principle ICNs of the human brain as defined by a standardized functional connectivity atlas. Amyloid deposition in AD dementia showed a preference for the DMN, but high effect sizes were also observed for other neocortical ICNs, most notably the frontoparietal-control network. Atrophic changes were most specific for an anterior limbic network, followed by the DMN, whereas other neocortical networks were relatively spared. Hypometabolism appeared to be a mixture of both amyloid- and atrophy-related profiles. Similar patterns of modality-dependent network specificity were also observed in the predementia and, for amyloid deposition, in the preclinical stage. These quantitative data confirm a high vulnerability of the DMN for multimodal imaging abnormalities in AD. However, rather than being selective for the DMN, imaging abnormalities more generally affect higher order cognitive networks and, importantly, the vulnerability profiles of these networks markedly differ for distinct aspects of AD pathology. © 2015 Wiley Periodicals, Inc.

  17. Learning by Knowledge Networking across Cultures - The Experience of Joint Courses in Environmental Studies for Malaysian and Danish Engineering and Science students

    DEFF Research Database (Denmark)

    Wangel, Arne; Stærdahl, Jens; Bransholm Pedersen, Kirsten

    2003-01-01

    Engineers and planners working in trans-national production and aid project interventions in Third World countries must be able to 're-invent' technological systems across cultures and plan and build capacities of their counterparts. A series of joint courses on cleaner production (CP) and enviro......Engineers and planners working in trans-national production and aid project interventions in Third World countries must be able to 're-invent' technological systems across cultures and plan and build capacities of their counterparts. A series of joint courses on cleaner production (CP...... of the obstacles into resources for knowledge sharing. However, students have stressed their positive experience of cross-cultural communication. While a joint course of three-week duration by itself may involve only limited cross-cultural learning, serving primarily as an introduction to a long-term field study...

  18. Psychosocial Predictors of Students’ Use of Social Networking Sites: The Role of Culture, Self-Construals, Psychological Well-Being and Personality

    OpenAIRE

    Lee, Soon

    2017-01-01

    The thesis aimed to examine the significance of psychosocial factors (culture, self-construal, psychological well-being, and personality) in predicting SNS usages. Three quantitative studies were conducted. The first study identified cross-cultural differences in SNS usages between Malaysia, South Korea and China, and found the significance of the self-construal in predicting SNS usages. The second study revealed the significance of the severity of depression and OCD symptoms in predicting pa...

  19. Statistical Inference for Cultural Consensus Theory

    Science.gov (United States)

    2014-02-24

    Social Network Conference XXXII , Redondo Beach, California, March 2012. Agrawal, K. (Presenter), and Batchelder, W. H. Cultural Consensus Theory...Aggregating Complete Signed Graphs Under a Balance Constraint -- Part 2. International Sunbelt Social Network Conference XXXII , Redondo Beach

  20. Incidence and Trends of Infections with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance - Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2013-2016.

    Science.gov (United States)

    Marder, Ellyn P; Cieslak, Paul R; Cronquist, Alicia B; Dunn, John; Lathrop, Sarah; Rabatsky-Ehr, Therese; Ryan, Patricia; Smith, Kirk; Tobin-D'Angelo, Melissa; Vugia, Duc J; Zansky, Shelley; Holt, Kristin G; Wolpert, Beverly J; Lynch, Michael; Tauxe, Robert; Geissler, Aimee L

    2017-04-21

    Foodborne diseases represent a substantial public health concern in the United States. CDC's Foodborne Diseases Active Surveillance Network (FoodNet) monitors cases reported from 10 U.S. sites* of laboratory-diagnosed infections caused by nine enteric pathogens commonly transmitted through food. This report describes preliminary surveillance data for 2016 on the nine pathogens and changes in incidences compared with 2013-2015. In 2016, FoodNet identified 24,029 infections, 5,512 hospitalizations, and 98 deaths caused by these pathogens. The use of culture-independent diagnostic tests (CIDTs) by clinical laboratories to detect enteric pathogens has been steadily increasing since FoodNet began surveying clinical laboratories in 2010 (1). CIDTs complicate the interpretation of FoodNet surveillance data because pathogen detection could be affected by changes in health care provider behaviors or laboratory testing practices (2). Health care providers might be more likely to order CIDTs because these tests are quicker and easier to use than traditional culture methods, a circumstance that could increase pathogen detection (3). Similarly, pathogen detection could also be increasing as clinical laboratories adopt DNA-based syndromic panels, which include pathogens not often included in routine stool culture (4,5). In addition, CIDTs do not yield isolates, which public health officials rely on to distinguish pathogen subtypes, determine antimicrobial resistance, monitor trends, and detect outbreaks. To obtain isolates for infections identified by CIDTs, laboratories must perform reflex culture † ; if clinical laboratories do not, the burden of culturing falls to state public health laboratories, which might not be able to absorb that burden as the adoption of these tests increases (2). Strategies are needed to preserve access to bacterial isolates for further characterization and to determine the effect of changing trends in testing practices on surveillance.

  1. Reactive oxygen species levels and DNA fragmentation on astrocytes in primary culture after acute exposure to low intensity microwave electromagnetic field.

    Science.gov (United States)

    Campisi, Agata; Gulino, Marisa; Acquaviva, Rosaria; Bellia, Paolo; Raciti, Giuseppina; Grasso, Rosaria; Musumeci, Francesco; Vanella, Angelo; Triglia, Antonio

    2010-03-31

    The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields (EMF) in the microwave range was studied. Differentiated astroglial cell cultures at 14 days in vitro were exposed for 5, 10, or 20min to either 900MHz continuous waves or 900MHz waves modulated in amplitude at 50Hz using a sinusoidal waveform and 100% modulation index. The strength of the electric field (rms value) at the sample position was 10V/m. No change in cellular viability evaluated by MTT test and lactate dehydrogenase release was observed. A significant increase in ROS levels and DNA fragmentation was found only after exposure of the astrocytes to modulated EMF for 20min. No evident effects were detected when shorter time intervals or continuous waves were used. The irradiation conditions allowed the exclusion of any possible thermal effect. Our data demonstrate, for the first time, that even acute exposure to low intensity EMF induces ROS production and DNA fragmentation in astrocytes in primary cultures, which also represent the principal target of modulated EMF. Our findings also suggest the hypothesis that the effects could be due to hyperstimulation of the glutamate receptors, which play a crucial role in acute and chronic brain damage. Furthermore, the results show the importance of the amplitude modulation in the interaction between EMF and neocortical astrocytes. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  2. Changes in the Excitability of Neocortical Neurons in a Mouse Model of Amyotrophic Lateral Sclerosis Are Not Specific to Corticospinal Neurons and Are Modulated by Advancing Disease.

    Science.gov (United States)

    Kim, Juhyun; Hughes, Ethan G; Shetty, Ashwin S; Arlotta, Paola; Goff, Loyal A; Bergles, Dwight E; Brown, Solange P

    2017-09-13

    Cell type-specific changes in neuronal excitability have been proposed to contribute to the selective degeneration of corticospinal neurons in amyotrophic lateral sclerosis (ALS) and to neocortical hyperexcitability, a prominent feature of both inherited and sporadic variants of the disease, but the mechanisms underlying selective loss of specific cell types in ALS are not known. We analyzed the physiological properties of distinct classes of cortical neurons in the motor cortex of hSOD1 G93A mice of both sexes and found that they all exhibit increases in intrinsic excitability that depend on disease stage. Targeted recordings and in vivo calcium imaging further revealed that neurons adapt their functional properties to normalize cortical excitability as the disease progresses. Although different neuron classes all exhibited increases in intrinsic excitability, transcriptional profiling indicated that the molecular mechanisms underlying these changes are cell type specific. The increases in excitability in both excitatory and inhibitory cortical neurons show that selective dysfunction of neuronal cell types cannot account for the specific vulnerability of corticospinal motor neurons in ALS. Furthermore, the stage-dependent alterations in neuronal function highlight the ability of cortical circuits to adapt as disease progresses. These findings show that both disease stage and cell type must be considered when developing therapeutic strategies for treating ALS. SIGNIFICANCE STATEMENT It is not known why certain classes of neurons preferentially die in different neurodegenerative diseases. It has been proposed that the enhanced excitability of affected neurons is a major contributor to their selective loss. We show using a mouse model of amyotrophic lateral sclerosis (ALS), a disease in which corticospinal neurons exhibit selective vulnerability, that changes in excitability are not restricted to this neuronal class and that excitability does not increase

  3. Hippocampal and neocortical metabolite ratio in patients with complex partial seizure: short TE and long TE techniques using single voxel proton MR spectroscopy

    International Nuclear Information System (INIS)

    Chung, Jin Il; Kim, Dong Ik; Lee, Byung In; Lee, Seung Ik; Yoon, Pyeong Ho

    2000-01-01

    To compare hippocampal and neocortical metabolite ratios using single-voxel proton MR spectroscopy with different echo times in patients with complex partial seizure. Using a GE Signa 1.5T scanner with STEAM and PRESS sequences, automated single voxel proton MRS was used to determine metabolite ratio differences in the hippocampus and neocortex of nine complex partial seizure patients (mesial temporal sclerosis (n=3D5), status epilepticus (n=3D1), tumor (n=3D1), cortical dysplasia (n=3D1), occipital lobe epilepsy (n=3D1)). A total of 20 examinations were performed in the region of the hippocampus (n=3D17), temporal neocortex (n=3D1), and parieto-occipital gray matter (n=3D1). Voxel size range was 5.2-17.4 cm 3 . The calculated creatine (Cr) peak was employed as an internal reference and the relative ratio of N-acetylaspartate (NAA) and choline (Cho) was calculated for both short and long echo times using an automated PROBE/SV (GE Medical Systems) package. Each NAA/Cho ratio obtained using both PRESS and STEAM techniques was compared by means of statistical analysis (paired Student t-test). Using PRESS (long TE, 272 ms), NAA/Cho ratios were successfully calculated in 16 of 20 examinations; in four this was not possible due to noise levels of the Cr and Cho peaks. Using STEAM (short TE, 30 ms) NAA/Cho ratios were successfully calculated in 19 of 20 examinations; in one, the Cho peak could not be measured. Using PRESS and STEAM, mean and standard deviations for the NAA/Cho ratio were 1.22±0.50 and 1.16±0.36, respectively. There were no statistically significant differences in this ratio between the short and long TE method (p less than 0.01). In complex partial seizure patients, no significant metabolite differences were found between short and long echo times of single voxel proton MR spectroscopy. The metabolite ratio at different echo times can be reliably obtained using this simplified and automated PROBE/SV quantitation method. (author)

  4. Hippocampal and neocortical metabolite ratio in patients with complex partial seizure: short TE and long TE techniques using single voxel proton MR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Jin Il; Kim, Dong Ik; Lee, Byung In; Lee, Seung Ik; Yoon, Pyeong Ho [Medical College, Yonsei University, Seoul (Korea, Republic of)

    2000-08-01

    To compare hippocampal and neocortical metabolite ratios using single-voxel proton MR spectroscopy with different echo times in patients with complex partial seizure. Using a GE Signa 1.5T scanner with STEAM and PRESS sequences, automated single voxel proton MRS was used to determine metabolite ratio differences in the hippocampus and neocortex of nine complex partial seizure patients (mesial temporal sclerosis (n=3D5), status epilepticus (n=3D1), tumor (n=3D1), cortical dysplasia (n=3D1), occipital lobe epilepsy (n=3D1)). A total of 20 examinations were performed in the region of the hippocampus (n=3D17), temporal neocortex (n=3D1), and parieto-occipital gray matter (n=3D1). Voxel size range was 5.2-17.4 cm{sup 3}. The calculated creatine (Cr) peak was employed as an internal reference and the relative ratio of N-acetylaspartate (NAA) and choline (Cho) was calculated for both short and long echo times using an automated PROBE/SV (GE Medical Systems) package. Each NAA/Cho ratio obtained using both PRESS and STEAM techniques was compared by means of statistical analysis (paired Student t-test). Using PRESS (long TE, 272 ms), NAA/Cho ratios were successfully calculated in 16 of 20 examinations; in four this was not possible due to noise levels of the Cr and Cho peaks. Using STEAM (short TE, 30 ms) NAA/Cho ratios were successfully calculated in 19 of 20 examinations; in one, the Cho peak could not be measured. Using PRESS and STEAM, mean and standard deviations for the NAA/Cho ratio were 1.22{+-}0.50 and 1.16{+-}0.36, respectively. There were no statistically significant differences in this ratio between the short and long TE method (p less than 0.01). In complex partial seizure patients, no significant metabolite differences were found between short and long echo times of single voxel proton MR spectroscopy. The metabolite ratio at different echo times can be reliably obtained using this simplified and automated PROBE/SV quantitation method. (author)

  5. Urine culture

    Science.gov (United States)

    Culture and sensitivity - urine ... when urinating. You also may have a urine culture after you have been treated for an infection. ... when bacteria or yeast are found in the culture. This likely means that you have a urinary ...

  6. Safeguards Culture

    Energy Technology Data Exchange (ETDEWEB)

    Frazar, Sarah L.; Mladineo, Stephen V.

    2012-07-01

    The concepts of nuclear safety and security culture are well established; however, a common understanding of safeguards culture is not internationally recognized. Supported by the National Nuclear Security Administration, the authors prepared this report, an analysis of the concept of safeguards culture, and gauged its value to the safeguards community. The authors explored distinctions between safeguards culture, safeguards compliance, and safeguards performance, and evaluated synergies and differences between safeguards culture and safety/security culture. The report concludes with suggested next steps.

  7. Organizational culture

    OpenAIRE

    Schein, Edgar H.

    1988-01-01

    Cultural orientations of an organization can be its greatest strength, providing the basis for problem solving, cooperation, and communication. Culture, however, can also inhibit needed changes. Cultural changes typically happen slowly – but without cultural change, many other organizational changes are doomed to fail. The dominant culture of an organization is a major contributor to its success. But, of course, no organizational culture is purely one type or another. And the existence of sec...

  8. Digital culture as a converging paradigm for technology and culture: Challenges for the culture sector

    Directory of Open Access Journals (Sweden)

    Aleksandra Uzelac

    2010-05-01

    Full Text Available Digital culture is a new and complex concept. Digital advances are increasingly interacting with the world of culture and the arts, leading to a convergence of technologies, media and information and shaping communication modes. The new possibilities offered by the digital technologies -namely, global connectivity and the emergence of new networks- challenge our traditional understanding of culture and make it necessary for us to take on the board the concept of a digital culture. This article views digital culture as a new social system that determines experiences and opportunities for the citizens of today. Digital technologies and the networked environment have introduced new practices, opportunities and threats, and the culture sector needs to find appropriate ways for operating in this new reality.

  9. Cultural entrepreneurship

    NARCIS (Netherlands)

    A. Klamer (Arjo)

    2011-01-01

    textabstractCultural entrepreneurship is a new character in the cultural sector. This paper characterizes the cultural entrepreneur paying homage to the hermeneutic approach of Don Lavoie and others. The challenge is to render the "cultural" meaningful. An invention is the highlighting of the

  10. Industrial cultures

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    1996-01-01

    The chapter deals with different paradigms andtheories of cultural development. The problem toexplain change and methods to analyse developmentin different cultures are presented and discussed.......The chapter deals with different paradigms andtheories of cultural development. The problem toexplain change and methods to analyse developmentin different cultures are presented and discussed....

  11. Networks around entrepreneurs

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Ashourizadeh, Shayegheh; Jensen, Kent Wickstrøm

    2017-01-01

    Purpose: Entrepreneurs are networking with others to get advice for their businesses. The networking differs between men and women; notably, men are more often networking in the public sphere and women are more often networking in the private sphere. The aim here is to account for how such gender......Purpose: Entrepreneurs are networking with others to get advice for their businesses. The networking differs between men and women; notably, men are more often networking in the public sphere and women are more often networking in the private sphere. The aim here is to account for how...... such gendering of entrepreneurs’ networks differ between societies and cultures. Research Design: Based on survey data from the Global Entrepreneurships Monitor, a sample of 16,365 entrepreneurs is used to compare the gendering of entrepreneurs’ networks in China, and five countries largely located around...... the Persian Gulf, namely Yemen, Iran, Saudi Arabia, Qatar and United Arab Emirates. Findings: Analyses show that female entrepreneurs tend to have slightly larger private sphere networks than male entrepreneurs. The differences between male and female entrepreneurs’ networking in the public sphere...

  12. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  13. Urban sharing culture

    DEFF Research Database (Denmark)

    Fjalland, Emmy Laura Perez

    of the structures of the networked urban mobilities and holds the potentials to change the future mobilities. References Bauman, Zygmunt. 2000. Liquid Modernity. Cambridge: Polity. Beck, Ulrich. 1992. Risk Society: Towards a New Modernity (Published in Association with Theory, Culture & Society). London: SAGE......In urban areas sharing cultures, services and economies are rising. People share, rent and recycle their homes, cars, bikes, rides, tools, cloths, working space, knowhow and so on. The sharing culture can be understood as mobilities (Kesselring and Vogl 2013) of goods, values and ideas reshaping...... problems and side effects from concentration of consumption and contamination; and due to the shift from ownership to access it change our basic social cultural norms (Sayer 2005; Sayer 2011) about the ‘good’ life and social status (Freudendal-Pedersen 2007), commons and individuality, responsibility...

  14. ORGANIZATIONAL CULTURE AND MANAGEMENT CULTURE

    OpenAIRE

    Tudor Hobeanu; Loredana Vacarescu Hobeanu

    2010-01-01

    Communication reveals the importance of organizational culture and management culture supported by the remarkable results in economic and social level of organization. Their functions are presented and specific ways of expression levels of organizational culture and ways of adapting to the requirements of the organization's management culture.

  15. [Social networks in drinking behaviors among Japanese: support network, drinking network, and intervening network].

    Science.gov (United States)

    Yoshihara, Chika; Shimizu, Shinji

    2005-10-01

    The national representative sample was analyzed to examine the relationship between respondents' drinking practice and the social network which was constructed of three different types of network: support network, drinking network, and intervening network. Non-parametric statistical analysis was conducted with chi square method and ANOVA analysis, due to the risk of small samples in some basic tabulation cells. The main results are as follows: (1) In the support network of workplace associates, moderate drinkers enjoyed much more sociable support care than both nondrinkers and hard drinkers, which might suggest a similar effect as the French paradox. Meanwhile in the familial and kinship network, the more intervening care support was provided, the harder respondents' drinking practice. (2) The drinking network among Japanese people for both sexes is likely to be convergent upon certain types of network categories and not decentralized in various categories. This might reflect of the drinking culture of Japan, which permits people to drink everyday as a practice, especially male drinkers. Subsequently, solitary drinking is not optional for female drinkers. (3) Intervening network analysis showed that the harder the respondents' drinking practices, the more frequently their drinking behaviors were checked in almost all the categories of network. A rather complicated gender double-standard was found in the network of hard drinkers with their friends, particularly for female drinkers. Medical professionals played a similar intervening role for men as family and kinship networks but to a less degree than friends for females. The social network is considerably associated with respondents' drinking, providing both sociability for moderate drinkers and intervention for hard drinkers, depending on network categories. To minimize the risk of hard drinking and advance self-healthy drinking there should be more research development on drinking practice and the social network.

  16. Genome Wide Expression Profiling of Cancer Cell Lines Cultured in Microgravity Reveals Significant Dysregulation of Cell Cycle and MicroRNA Gene Networks.

    Directory of Open Access Journals (Sweden)

    Prasanna Vidyasekar

    Full Text Available Zero gravity causes several changes in metabolic and functional aspects of the human body and experiments in space flight have demonstrated alterations in cancer growth and progression. This study reports the genome wide expression profiling of a colorectal cancer cell line-DLD-1, and a lymphoblast leukemic cell line-MOLT-4, under simulated microgravity in an effort to understand central processes and cellular functions that are dysregulated among both cell lines. Altered cell morphology, reduced cell viability and an aberrant cell cycle profile in comparison to their static controls were observed in both cell lines under microgravity. The process of cell cycle in DLD-1 cells was markedly affected with reduced viability, reduced colony forming ability, an apoptotic population and dysregulation of cell cycle genes, oncogenes, and cancer progression and prognostic markers. DNA microarray analysis revealed 1801 (upregulated and 2542 (downregulated genes (>2 fold in DLD-1 cultures under microgravity while MOLT-4 cultures differentially expressed 349 (upregulated and 444 (downregulated genes (>2 fold under microgravity. The loss in cell proliferative capacity was corroborated with the downregulation of the cell cycle process as demonstrated by functional clustering of DNA microarray data using gene ontology terms. The genome wide expression profile also showed significant dysregulation of post transcriptional gene silencing machinery and multiple microRNA host genes that are potential tumor suppressors and proto-oncogenes including MIR22HG, MIR17HG and MIR21HG. The MIR22HG, a tumor-suppressor gene was one of the highest upregulated genes in the microarray data showing a 4.4 log fold upregulation under microgravity. Real time PCR validated the dysregulation in the host gene by demonstrating a 4.18 log fold upregulation of the miR-22 microRNA. Microarray data also showed dysregulation of direct targets of miR-22, SP1, CDK6 and CCNA2.

  17. Cultural commons and cultural evolution

    OpenAIRE

    Bravo, Giangiacomo

    2010-01-01

    Culture evolves following a process that is akin to biological evolution, although with some significant differences. At the same time culture has often a collective good value for human groups. This paper studies culture in an evolutionary perspective, with a focus on the implications of group definition for the coexistence of different cultures. A model of cultural evolution is presented where agents interacts in an artificial environment. The belonging to a specific memetic group is a majo...

  18. Karg, S. New projects within the FLAX Network. In: Karg S. (ed.) Flax (Linum usitatissimum L.) - a natural resource for food and textiles for 8000 years. Cross-disciplinary investigations on the evolution and cultural history of flax and linen. Programme and abstracts of the second

    DEFF Research Database (Denmark)

    Karg, Sabine

    2010-01-01

    Karg, S. New projects within the FLAX Network. In: Karg S. (ed.) Flax (Linum usitatissimum L.) - a natural resource for food and textiles for 8000 years. Cross-disciplinary investigations on the evolution and cultural history of flax and linen. Programme and abstracts of the second workshop 28...

  19. Inference of neuronal network spike dynamics and topology from calcium imaging data

    Directory of Open Access Journals (Sweden)

    Henry eLütcke

    2013-12-01

    Full Text Available Two-photon calcium imaging enables functional analysis of neuronal circuits by inferring action potential (AP occurrence ('spike trains' from cellular fluorescence signals. It remains unclear how experimental parameters such as signal-to-noise ratio (SNR and acquisition rate affect spike inference and whether additional information about network structure can be extracted. Here we present a simulation framework for quantitatively assessing how well spike dynamics and network topology can be inferred from noisy calcium imaging data. For simulated AP-evoked calcium transients in neocortical pyramidal cells, we analyzed the quality of spike inference as a function of SNR and data acquisition rate using a recently introduced peeling algorithm. Given experimentally attainable values of SNR and acquisition rate, neural spike trains could be reconstructed accurately and with up to millisecond precision. We then applied statistical neuronal network models to explore how remaining uncertainties in spike inference affect estimates of network connectivity and topological features of network organization. We define the experimental conditions suitable for inferring whether the network has a scale-free structure and determine how well hub neurons can be identified. Our findings provide a benchmark for future calcium imaging studies that aim to reliably infer neuronal network properties.

  20. The cultural contagion of conflict

    Science.gov (United States)

    Gelfand, Michele; Shteynberg, Garriy; Lee, Tiane; Lun, Janetta; Lyons, Sarah; Bell, Chris; Chiao, Joan Y.; Bruss, C. Bayan; Al Dabbagh, May; Aycan, Zeynep; Abdel-Latif, Abdel-Hamid; Dagher, Munqith; Khashan, Hilal; Soomro, Nazar

    2012-01-01

    Anecdotal evidence abounds that conflicts between two individuals can spread across networks to involve a multitude of others. We advance a cultural transmission model of intergroup conflict where conflict contagion is seen as a consequence of universal human traits (ingroup preference, outgroup hostility; i.e. parochial altruism) which give their strongest expression in particular cultural contexts. Qualitative interviews conducted in the Middle East, USA and Canada suggest that parochial altruism processes vary across cultural groups and are most likely to occur in collectivistic cultural contexts that have high ingroup loyalty. Implications for future neuroscience and computational research needed to understand the emergence of intergroup conflict are discussed. PMID:22271785

  1. Memory consolidation from seconds to weeks: A three-stage neural network model with autonomous reinstatement dynamics

    Directory of Open Access Journals (Sweden)

    Florian eFiebig

    2014-07-01

    Full Text Available Declarative long-term memories are not created at an instant. Gradual stabilization and temporally shifting dependence of acquired declarative memories on different brain regions - called systems consolidation - can be tracked in time by lesion experiments. The observation of temporally graded retrograde amnesia following hippocampal lesions, points to a gradual transfer of memory from hippocampus to neocortical long-term memory. Spontaneous reactivations of hippocampal memories, as observed in place cell reactivations during slow-wave-sleep, are supposed to drive neocortical reinstatements and facilitate this process.We propose a functional neural network implementation of these ideas and furthermore suggest an extended three-stage framework that also includes the prefrontal cortex and bridges the temporal chasm between working memory percepts on the scale of seconds and consolidated long-term memory on the scale of weeks or months.We show that our three-stage model can autonomously produce the necessary stochastic reactivation dynamics for successful episodic memory consolidation. The resulting learning system is shown to exhibit classical memory effects seen in experimental studies, such as retrograde and anterograde amnesia after simulated hippocampal lesioning; furthermore the model reproduces peculiar biological findings on memory modulation, such as retrograde facilitation of memory after suppressed acquisition of new long-term memories - similar to the effects of benzodiazepines on memory.

  2. Culturing Protozoa.

    Science.gov (United States)

    Stevenson, Paul

    1980-01-01

    Compares various nutrient media, growth conditions, and stock solutions used in culturing protozoa. A hay infusion in Chalkey's solution maintained at a stable temperature is recommended for producing the most dense and diverse cultures. (WB)

  3. Safety culture

    International Nuclear Information System (INIS)

    Keen, L.J.

    2003-01-01

    Safety culture has become a topic of increasing interest for industry and regulators as issues are raised on safety problems around the world. The keys to safety culture are organizational effectiveness, effective communications, organizational learning, and a culture that encourages the identification and resolution of safety issues. The necessity of a strong safety culture places an onus on all of us to continually question whether the safety measures already in place are sufficient, and are being applied. (author)

  4. Beyond Culture.

    Science.gov (United States)

    Barron, Daniel D.

    1993-01-01

    Discusses the lack of literature relating to cultural differences and school library media programs and reviews the book "Beyond Culture" by Edward T. Hall. Highlights include the population/environment crisis, cultural literacy, the use of technology, and Marshall McLuhan's idea of the global village. (LRW)

  5. Bile culture

    Science.gov (United States)

    Culture - bile ... is placed in a special dish called a culture medium to see if bacteria, viruses, or fungi ... Chernecky CC, Berger BJ. Body fluid - anaerobic culture. In: ... . 6th ed. St Louis, MO: Elsevier Saunders; 2013:225-226. Kim AY, ...

  6. Handling Culture

    NARCIS (Netherlands)

    Pieter van Nispen tot Pannerden

    2011-01-01

    The article indicates how companies may prepare for and deal with cultural differences. Because the research base is still rather limited an overall perspective may not be realised. After discussing definitions and concepts of culture, as well as values, cultural differences between states are

  7. Exploring network organization in practice

    DEFF Research Database (Denmark)

    Hu, Yimei; Sørensen, Olav Jull

    Constructing a network organization for global R&D is presented as a common sense practice in existing literature. However, there are still queries about the network organization, such as the persistence of hierarchies which make a network organization merely a “bureaucracy-lite” organization....... Furthermore, in practice, we rarely see radical organizational change towards a network organization that adopts an internal market. The co-existence of market, hierarchy and network triggered research interest. A multiple case study of three transnational corporations’ global R&D organization shows...... that there are different logical considerations when designing a network organization to facilitate innovation. I identify three types of network organizations: market-led, directed and culture-led network organizations. Different types of network organizations show that organizations are dual and even ternary systems...

  8. Emergence of Functional Specificity in Balanced Networks with Synaptic Plasticity.

    Directory of Open Access Journals (Sweden)

    Sadra Sadeh

    2015-06-01

    studies of sensory processing in neocortical network models equipped with synaptic plasticity.

  9. Cortical neurons and networks are dormant but fully responsive during isoelectric brain state.

    Science.gov (United States)

    Altwegg-Boussac, Tristan; Schramm, Adrien E; Ballestero, Jimena; Grosselin, Fanny; Chavez, Mario; Lecas, Sarah; Baulac, Michel; Naccache, Lionel; Demeret, Sophie; Navarro, Vincent; Mahon, Séverine; Charpier, Stéphane

    2017-09-01

    A continuous isoelectric electroencephalogram reflects an interruption of endogenously-generated activity in cortical networks and systematically results in a complete dissolution of conscious processes. This electro-cerebral inactivity occurs during various brain disorders, including hypothermia, drug intoxication, long-lasting anoxia and brain trauma. It can also be induced in a therapeutic context, following the administration of high doses of barbiturate-derived compounds, to interrupt a hyper-refractory status epilepticus. Although altered sensory responses can be occasionally observed on an isoelectric electroencephalogram, the electrical membrane properties and synaptic responses of individual neurons during this cerebral state remain largely unknown. The aim of the present study was to characterize the intracellular correlates of a barbiturate-induced isoelectric electroencephalogram and to analyse the sensory-evoked synaptic responses that can emerge from a brain deprived of spontaneous electrical activity. We first examined the sensory responsiveness from patients suffering from intractable status epilepticus and treated by administration of thiopental. Multimodal sensory responses could be evoked on the flat electroencephalogram, including visually-evoked potentials that were significantly amplified and delayed, with a high trial-to-trial reproducibility compared to awake healthy subjects. Using an analogous pharmacological procedure to induce prolonged electro-cerebral inactivity in the rat, we could describe its cortical and subcortical intracellular counterparts. Neocortical, hippocampal and thalamo-cortical neurons were all silent during the isoelectric state and displayed a flat membrane potential significantly hyperpolarized compared with spontaneously active control states. Nonetheless, all recorded neurons could fire action potentials in response to intracellularly injected depolarizing current pulses and their specific intrinsic

  10. Spatial Culture

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2012-01-01

    Spatial Culture – A Humanities Perspective Abstract of introductory essay by Henrik Reeh Secured by alliances between socio-political development and cultural practices, a new field of humanistic studies in spatial culture has developed since the 1990s. To focus on links between urban culture...... and modern society is, however, an intellectual practice which has a much longer history. Already in the 1980s, the debate on the modern and the postmodern cited Paris and Los Angeles as spatio-cultural illustrations of these major philosophical concepts. Earlier, in the history of critical studies, the work...... Foucault considered a constitutive feature of 20th-century thinking and one that continues to occupy intellectual and cultural debates in the third millennium. A conceptual framework is, nevertheless, necessary, if the humanities are to adequa-tely address city and space – themes that have long been...

  11. Opinion evolution in different social acquaintance networks.

    Science.gov (United States)

    Chen, Xi; Zhang, Xiao; Wu, Zhan; Wang, Hongwei; Wang, Guohua; Li, Wei

    2017-11-01

    Social acquaintance networks influenced by social culture and social policy have a great impact on public opinion evolution in daily life. Based on the differences between socio-culture and social policy, three different social acquaintance networks (kinship-priority acquaintance network, independence-priority acquaintance network, and hybrid acquaintance network) incorporating heredity proportion p h and variation proportion p v are proposed in this paper. Numerical experiments are conducted to investigate network topology and different phenomena during opinion evolution, using the Deffuant model. We found that in kinship-priority acquaintance networks, similar to the Chinese traditional acquaintance networks, opinions always achieve fragmentation, resulting in the formation of multiple large clusters and many small clusters due to the fact that individuals believe more in their relatives and live in a relatively closed environment. In independence-priority acquaintance networks, similar to Western acquaintance networks, the results are similar to those in the kinship-priority acquaintance network. In hybrid acquaintance networks, similar to the Chinese modern acquaintance networks, only a few clusters are formed indicating that in modern China, opinions are more likely to reach consensus on a large scale. These results are similar to the opinion evolution phenomena in modern society, proving the rationality and applicability of network models combined with social culture and policy. We also found a threshold curve p v +2p h =2.05 in the results for the final opinion clusters and evolution time. Above the threshold curve, opinions could easily reach consensus. Based on the above experimental results, a culture-policy-driven mechanism for the opinion dynamic is worth promoting in this paper, that is, opinion dynamics can be driven by different social cultures and policies through the influence of heredity and variation in interpersonal relationship networks. This

  12. Opinion evolution in different social acquaintance networks

    Science.gov (United States)

    Chen, Xi; Zhang, Xiao; Wu, Zhan; Wang, Hongwei; Wang, Guohua; Li, Wei

    2017-11-01

    Social acquaintance networks influenced by social culture and social policy have a great impact on public opinion evolution in daily life. Based on the differences between socio-culture and social policy, three different social acquaintance networks (kinship-priority acquaintance network, independence-priority acquaintance network, and hybrid acquaintance network) incorporating heredity proportion ph and variation proportion pv are proposed in this paper. Numerical experiments are conducted to investigate network topology and different phenomena during opinion evolution, using the Deffuant model. We found that in kinship-priority acquaintance networks, similar to the Chinese traditional acquaintance networks, opinions always achieve fragmentation, resulting in the formation of multiple large clusters and many small clusters due to the fact that individuals believe more in their relatives and live in a relatively closed environment. In independence-priority acquaintance networks, similar to Western acquaintance networks, the results are similar to those in the kinship-priority acquaintance network. In hybrid acquaintance networks, similar to the Chinese modern acquaintance networks, only a few clusters are formed indicating that in modern China, opinions are more likely to reach consensus on a large scale. These results are similar to the opinion evolution phenomena in modern society, proving the rationality and applicability of network models combined with social culture and policy. We also found a threshold curve pv+2 ph=2.05 in the results for the final opinion clusters and evolution time. Above the threshold curve, opinions could easily reach consensus. Based on the above experimental results, a culture-policy-driven mechanism for the opinion dynamic is worth promoting in this paper, that is, opinion dynamics can be driven by different social cultures and policies through the influence of heredity and variation in interpersonal relationship networks. This

  13. Cultural contrast

    Institute of Scientific and Technical Information of China (English)

    周志

    2016-01-01

    Chinese cultural contains a great number of styles;culture differentiation does not depend on region differentiation.This research would interpret what difference between Hong Kong and Shenzhen.1.Food culture in china Traditional Chinese medicine suggests eating local seasonal fruit and vegetables,as they are most suitable for the body during a particular season.It is also divided food into 3 characteristics:cooling foods,warming foods and balance or

  14. Culture evolves

    OpenAIRE

    Whiten, Andrew; Hinde, Robert A.; Laland, Kevin N.; Stringer, Christopher B.

    2011-01-01

    Culture pervades human lives and has allowed our species to create niches all around the world and its oceans, in ways quite unlike any other primate. Indeed, our cultural nature appears so distinctive that it is often thought to separate humanity from the rest of nature and the Darwinian forces that shape it. A contrary view arises through the recent discoveries of a diverse range of disciplines, here brought together to illustrate the scope of a burgeoning field of cultural evolution and to...

  15. Manuscript Cultures

    DEFF Research Database (Denmark)

    What do Mesoamerica, Greece, Byzantium, Island, Chad, Ethiopia, India, Tibet, China and Japan have in common? Like many other cultures of the world, they share a particular form of cultural heritage: ancient handwritten documents. In 2007, scholars from some20 countries around the world gathered...... at the University of Copenhagen for a workshop on manuscripts to compare notes. This event led to the publication of this volume, which brings together16 articles on philological, cultural, and material aspects of manuscripts in search for a common ground across disciplines and cultures....

  16. Skin or nail culture

    Science.gov (United States)

    Mucosal culture; Culture - skin; Culture - mucosal; Nail culture; Culture - fingernail; Fingernail culture ... There, it is placed in a special dish (culture). It is then watched to see if bacteria, ...

  17. Volumetric MRI for evaluation of regional pattern and progression of neocortical degeneration in Alzheimer's disease; MR-Volumetrie zur Darstellung von Verteilung und zeitlicher Abfolge neokortikaler Degeneration bei Morbus Alzheimer

    Energy Technology Data Exchange (ETDEWEB)

    Leinsinger, G. [Institut fuer Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Muenchen (Germany); Institut fuer Klinische Radiologie, LMU Muenchen, Ziemssenstrasse 1, 80336, Muenchen (Germany); Teipel, S.; Pruessner, J.; Hampel, H. [Klinik fuer Psychiatrie, Ludwig-Maximilians-Universitaet Muenchen, Muenchen (Germany); Wismueller, A.; Born, C.; Meindl, T.; Flatz, W.; Schoenberg, S.; Reiser, M. [Institut fuer Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Muenchen (Germany)

    2003-07-01

    Volumetric analysis of the corpus callosum and hippocampus using MRI in Alzheimer's disease (AD) to evaluate the regional pattern and progression of neocortical neurodegeneration. In subsequent studies we investigated patients with AD and healthy controls. Volumetry was based on MRI-data from a sagittal 3D T1w-gradient echo sequence. The corpus callosum (CC) was measured in a midsagittal slice, and subdivided into 5 subregions. Volumetry of the hippocampus/amygdala-formation (HAF) was performed by segmentation in coronary reoriented slices. In AD patients we found a significant atrophy in the rostrum und splenium of CC. The atrophy was correlated with the severity of dementia, but no correlation was found with the load of white matter lesions. In comparison with {sup 18}FDG-PET, we found a significant correlation of regional CC-atrophy with the regional decline of cortical glucose metabolism. A ROC-analysis demonstrated no significant differences in the diagostic accuracy of HAF volumetry and regional CC volumetry of the splenium (region C5) even in mild stages of dementia. Regional atrophy of CC can be used as a marker of neocortical degeneration even in early stages of dementia in AD. (orig.) [German] Volumetrische Analyse des Corpus callosum und Hippokampus mittels MRT bei der Alzheimer-Erkrankung (AD), mit dem Ziel die regionale Verteilung und Progression der neokortikalen relativ zur allokortikalen Neurodegeneration zu erfassen. In mehreren Studienabschnitten wurden Patienten mit AD und gesunde Kontrollen untersucht. Als Grundlage fuer die Volumetrie diente eine sagittale 3D-T1w-Gradientenechosequenz. Die Vermessung des Corpus callosum (CC) erfolgte in der mittsagittalen Schicht, wobei 5 Subregionen definiert wurden. Die Volumetrie des Hippokampus-Amygdala-Komplexes (HAK) wurde durch Segmentierung an koronar reorientierten Schichten durchgefuehrt. Bei Patienten mit AD fand sich eine signifikante Atrophie in Rostrum und Splenium des CC. Dabei zeigte sich

  18. Organizing Cultural Projects Through Legitimising as Cultural Entrepreneurship

    DEFF Research Database (Denmark)

    Lindkvist, Lars; Hjorth, Daniel

    2015-01-01

    Purpose This paper is a study of creating organization in the case of cultural projects; cultural entrepreneurship. This includes taking advantage of opportunities and using ones social capital through networks. It is a case study of Vandalorum which is an Swedish international art- and design...... and Design Centre. Findings The case of Vandalorum shows that organizing a cultural project like Vandalorum is characterized by no well-defined starting and stopping point, but – quite typically for entrepreneurship as an organization-creation process – builds momentum and legitimacy narratively. Originality...

  19. Declarative Networking

    CERN Document Server

    Loo, Boon Thau

    2012-01-01

    Declarative Networking is a programming methodology that enables developers to concisely specify network protocols and services, which are directly compiled to a dataflow framework that executes the specifications. Declarative networking proposes the use of a declarative query language for specifying and implementing network protocols, and employs a dataflow framework at runtime for communication and maintenance of network state. The primary goal of declarative networking is to greatly simplify the process of specifying, implementing, deploying and evolving a network design. In addition, decla

  20. Cultural probes

    DEFF Research Database (Denmark)

    Madsen, Jacob Østergaard

    The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation.......The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation....

  1. Cultural Communications.

    Science.gov (United States)

    Armas, Jose

    It is too often taken for granted that the communication process with culturally different children takes place as readily as it might with children from Anglo cultures. Most teachers receive training in verbal and formal communication skills; children come to school with nonverbal and informal communication skills. This initially can create…

  2. Connecting Culture

    DEFF Research Database (Denmark)

    Haugegaard, Rikke; Mynster Christensen, Maya

    2017-01-01

    The understanding of cultural dynamics in the area of operations is essential in to the accomplishment of military missions in international operations. The aim of this handbook is to introduce a tool enabling the use of culture as part of the military operational planning process....

  3. Stool Culture

    Science.gov (United States)

    ... infections and may be identified with a stool culture. Some important examples include: Escherichia coli 0157:H7 and other toxin- ... the toxin-producing C. difficile will be performed. Examples of other less common causes include: ... of stool cultures that are reported as negative usually reflect the ...

  4. Boosting Culture

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Culture makes up an indispensable part of our lives, just like material comfort. It is thought of as an important source of a nation’s vitality and creativity, and constitutes a key factor uniting the nation,while making it distinctive from other countries. It is also said culture is a productiv

  5. Internet culture

    CERN Document Server

    Porter, David

    2013-01-01

    The internet has recently grown from a fringe cultural phenomenon to a significant site of cultural production and transformation. Internet Culture maps this new domain of language, politics and identity, locating it within the histories of communication and the public sphere. Internet Culture offers a critical interrogation of the sustaining myths of the virtual world and of the implications of the current mass migration onto the electronic frontier. Among the topics discussed in Internet Culture are the virtual spaces and places created by the citizens of the Net and their claims to the hotly contested notion of "virtual community"; the virtual bodies that occupy such spaces; and the desires that animate these bodies. The contributors also examine the communication medium behind theworlds of the Net, analyzing the rhetorical conventions governing online discussion, literary antecedents,and potential pedagogical applications.

  6. Avatar Culture

    DEFF Research Database (Denmark)

    Koda, Tomoko; Ishida, Toru; Rehm, Matthias

    2009-01-01

    and Western designers. The goals of the study were: (1) to investigate cultural differences in avatar expression evaluation and apply findings from psychological studies of human facial expression recognition, (2) to identify expressions and design features that cause cultural differences in avatar facial...... expression interpretation. The results of our study confirmed that (1) there are cultural differences in interpreting avatars’ facial expressions, and the psychological theory that suggests physical proximity affects facial expression recognition accuracy is also applicable to avatar facial expressions, (2......Avatars are increasingly used to express our emotions in our online communications. Such avatars are used based on the assumption that avatar expressions are interpreted universally among all cultures. This paper investigated cross-cultural evaluations of avatar expressions designed by Japanese...

  7. CULTURAL TOURISM

    Directory of Open Access Journals (Sweden)

    Dana POP

    2016-07-01

    Full Text Available In this paper we will try to analyse the cultural tourism. We will start by referring to the complex concepts of tourism and culture and to the synergies existing between them. We will define cultural tourism and present its appearance and evolution as well as its importance as a modern form of tourism. We will present the various types of cultural tourism with their characteristics and the specific features of cultural tourists according to their interests. We will also mention that there are advantages and disadvantages for any kind of tourism depending on the position – local communities, companies or tourists. For the future we will refer to the new partnership between UNWTO and UNESCO.

  8. Field-theoretic approach to fluctuation effects in neural networks

    International Nuclear Information System (INIS)

    Buice, Michael A.; Cowan, Jack D.

    2007-01-01

    A well-defined stochastic theory for neural activity, which permits the calculation of arbitrary statistical moments and equations governing them, is a potentially valuable tool for theoretical neuroscience. We produce such a theory by analyzing the dynamics of neural activity using field theoretic methods for nonequilibrium statistical processes. Assuming that neural network activity is Markovian, we construct the effective spike model, which describes both neural fluctuations and response. This analysis leads to a systematic expansion of corrections to mean field theory, which for the effective spike model is a simple version of the Wilson-Cowan equation. We argue that neural activity governed by this model exhibits a dynamical phase transition which is in the universality class of directed percolation. More general models (which may incorporate refractoriness) can exhibit other universality classes, such as dynamic isotropic percolation. Because of the extremely high connectivity in typical networks, it is expected that higher-order terms in the systematic expansion are small for experimentally accessible measurements, and thus, consistent with measurements in neocortical slice preparations, we expect mean field exponents for the transition. We provide a quantitative criterion for the relative magnitude of each term in the systematic expansion, analogous to the Ginsburg criterion. Experimental identification of dynamic universality classes in vivo is an outstanding and important question for neuroscience

  9. Creating a Culture by Governance: Issues in Managing Culture

    Directory of Open Access Journals (Sweden)

    Ma. Victoria T. Herrera

    2001-12-01

    Full Text Available The management of culture involves a network of agencies, institutions and entities both from the public and private sectors. This is part of a collective process by which objects acwuire cultural significance. We create images of our nations, tell stories, and construct experiences for other people through exhibitions, festivals and other cultural activities. Our role is never neutral and it is important to recognize this power and the implications of our actions.In the Philippines, government has taken an active role in the production and management of culture. In spite of the relatively small percentage of funding spent on culture and the arts, it has extended support through various institutions and agencies that, at present, comprise a complex network. Through their respective programs, government has defined paths of cultural production-- from the larger policy framework for organizations to specific commemorative programs. Given this range of involvement, how has the state empowered people and organizations shape culture? What strategies has it taken to extend to support the production and distribution of culture?This paper focuses on two case studies that represent strategies the state has taken in cultural management. At a macro level, the changes the Cultural Center of the Philippines underwent reflect shifting policies and priorities. As products of changing political administrations, this institution went through a re-orientation of its mission. This came with an abrupt expansion in scale but without the necessary resources to support the CCP's new programs. At a micro level, the second evaluates the refurbished Rizal Shrine, Fort Santiago, one of the major projects of the now defunct National Centennial Commission. This underscores the need for a more transparent decision-making process, prioritizing the interest of the museum's public and not just that of the specialists who control the production of knowledge.

  10. Networks and Collaboration in Spanish Education Policy

    Science.gov (United States)

    Azorín, Cecilia M.; Muijs, Daniel

    2017-01-01

    Background: Networks play an important role in today's societies. As a consequence, changes are apparent in the political, economic, cultural, educational and social agendas. Purpose: The main goal of this article is to map the situation of school networks in Spain. The research questions are focused on what forms collaboration and networking take…

  11. Online Social Network Interactions:

    Directory of Open Access Journals (Sweden)

    Hui-Jung Chang

    2018-01-01

    Full Text Available A cross-cultural comparison of social networking structure on McDonald’s Facebook fan sites between Taiwan and the USA was conducted utilizing the individualism/collectivism dimension proposed by Hofstede. Four network indicators are used to describe the network structure of McDonald’s Facebook fan sites: size, density, clique and centralization. Individuals who post on both Facebook sites for the year of 2012 were considered as network participants for the purpose of the study. Due to the huge amount of data, only one thread of postings was sampled from each month of the year of 2012. The final data consists of 1002 postings written by 896 individuals and 5962 postings written by 5532 individuals from Taiwan and the USA respectively. The results indicated that the USA McDonald’s Facebook fan network has more fans, while Taiwan’s McDonald’s Facebook fan network is more densely connected. Cliques did form among the overall multiplex and within the individual uniplex networks in two countries, yet no significant differences were found between them. All the fan networks in both countries are relatively centralized, mostly on the site operators.

  12. Safety culture

    International Nuclear Information System (INIS)

    Drukraroff, C.

    2010-01-01

    The concept of Safety Culture was defined after Chernobyl's nuclear accident in 1986. It has not been exempt from discussion interpretations, adding riders, etc..., over the last 24 years because it has to do with human behavior and performance in the organizations. Safety Culture is not an easy task to define, assess and monitor. The proof of it is that today we still discussing and writing about it. How has been the evolution of Safety Culture at the Juzbado Factory since 1985 to today?. What is the strategy that we will be following in the future. (Author)

  13. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago Vanderlei; Giannitsarou, Chrysi; Johnson, CR

    2017-01-01

    We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and define a network aggregator that preserves network cohesion.

  14. Music Cultural Pedagogy in the "Network Society"

    Science.gov (United States)

    Sakai, Winfried

    2014-01-01

    The present contribution to theory construction in music educational research focuses on the contemporary requirements for general music education. One starting point are the normative claims of a democratic liberal education as to find in the field of critical pedagogy and the sociology of education. Another point of departure is provided by…

  15. The network researchers' network

    DEFF Research Database (Denmark)

    Henneberg, Stephan C.; Jiang, Zhizhong; Naudé, Peter

    2009-01-01

    The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987). In thi......The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987......). In this paper, based upon the papers presented at the 22 conferences held to date, we undertake a Social Network Analysis in order to examine the degree of co-publishing that has taken place between this group of researchers. We identify the different components in this database, and examine the large main...

  16. Paramilitary Culture.

    Science.gov (United States)

    Gibson, James William

    1989-01-01

    Identifies the movie, "Rambo," and "Soldier of Fortune" magazine as artifacts of "paramilitary culture." Contends that they are a social phenomenon which helps legitimate the United States government's rapid escalation of military forces. (MS)

  17. Rectal culture

    Science.gov (United States)

    ... have an infection of the rectum, such as gonorrhea . It may also be done instead of a ... infection. This may be: Bacterial infection Parasitic enterocolitis Gonorrhea Sometimes a culture shows that you are a ...

  18. A Socio-Cultural Model Based on Empirical Data of Cultural and Social Relationship

    DEFF Research Database (Denmark)

    Lipi, Afia Akhter; Nakano, Yukiko; Rehm, Matthias

    2010-01-01

    The goal of this paper is to integrate culture and social relationship as a computational term in an embodied conversational agent system by employing empirical and theoretical approach. We propose a parameter-based model that predicts nonverbal expressions appropriate for specific cultures...... in different social relationship. So, first, we introduce the theories of social and cultural characteristics. Then, we did corpus analysis of human interaction of two cultures in two different social situations and extracted empirical data and finally, by integrating socio-cultural characteristics...... with empirical data, we establish a parameterized network model that generates culture specific non-verbal expressions in different social relationships....

  19. Safety culture

    International Nuclear Information System (INIS)

    1991-01-01

    The response to a previous publication by the International Nuclear Safety Advisory Group (INSAG), indicated a broad international interest in expansion of the concept of Safety Culture, in such a way that its effectiveness in particular cases may be judged. This report responds to that need. In its manifestation, Safety Culture has two major components: the framework determined by organizational policy and by managerial action, and the response of individuals in working within and benefiting by the framework. 1 fig

  20. The Drama in Cross-Cultural Marriage

    African Journals Online (AJOL)

    As cultures from the sub-region of (Nigeria and then Africa), a continent which falls under those ... information networks and cross-cultural currents”. (IMF 101). ... that, globalisation is not about the 'integration of' but the 'opening up' of all ... growth and development, all parties concerned aspire to the same heights, view from ...

  1. Network cosmology.

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.

  2. European ecological networks and greenways

    DEFF Research Database (Denmark)

    Kristiansen, Ib; Jongman, Rob H.G.; Kulvik, Mart

    2004-01-01

    renewed. Within the framework of nature conservation, the notion of an ecological network has become increasingly important. Throughout Europe, regional and national approaches are in different phases of development, which are all based on recent landscape ecological principles. Ecological networks......In the context of European integration, networks are becoming increasingly important in both social and ecological sense. Since the beginning of the 1990s, societal and scientific exchanges are being restructured as the conceptual approaches towards new nature conservation strategies have been....... This complex interaction between cultural and natural features results in quite different ways for the elaboration of ecological networks and greenways....

  3. Urine culture - catheterized specimen

    Science.gov (United States)

    Culture - urine - catheterized specimen; Urine culture - catheterization; Catheterized urine specimen culture ... urinary tract infections may be found in the culture. This is called a contaminant. You may not ...

  4. Cultural tourism and tourism cultures

    DEFF Research Database (Denmark)

    Ooi, Can-Seng

    Presenting a comprehensive and dynamic understanding of cultural tourism, this volume examines cultural mediators and how they help tourists appreciate foreign cultures. It also shows how tourism experiences are strategically crafted by mediators, the complexity of the mediation process, and how...... various products are mediated differently. A number of different products are investigated, including destination brand identities, "living" cultures and everyday life, art and history. The author illustrates his arguments by comparing the tourism strategies of Copenhagen and Singapore, and demonstrates...... how tourism is an agent for social change. The author also offers an original and refreshing way of understanding tourist behaviour through the concept of the "versatile tourist". The book's empirical cases and dialogic framework provide new and deep insights into tourism activities. In his...

  5. Cultured Trash, Not Trash Culture

    Directory of Open Access Journals (Sweden)

    Taufiqurrohman Taufiqurrohman

    2017-09-01

    Full Text Available As civilized creature, human actually can manage trash as well as possible although it is often stereotyped as a vain thing. This article gives the proof that trash can be cultured as well so that a society can take benefits from the existence of it. This article parses ways of orderly managing it at schools, in this case two schools in Jepara. The results say that trash can be cultured by having an organization to manage the Trash Bank at schools and to train students to classify and recycle trash then take advantage of it by selling the collected and the recycled trash. It makes trash have good transformation of values, repelling against the prior stereotype. Finally, by taking example from Trash Bank management at schools, human can have so cultured trash that they would not be trapped by trash culture.

  6. Computational modeling of distinct neocortical oscillations driven by cell-type selective optogenetic drive: Separable resonant circuits controlled by low-threshold spiking and fast-spiking interneurons

    Directory of Open Access Journals (Sweden)

    Dorea Vierling-Claassen

    2010-11-01

    Full Text Available Selective optogenetic drive of fast spiking interneurons (FS leads to enhanced local field potential (LFP power across the traditional gamma frequency band (20-80Hz; Cardin et al., 2009. In contrast, drive to regular-spiking pyramidal cells (RS enhances power at lower frequencies, with a peak at 8 Hz. The first result is consistent with previous computational studies emphasizing the role of FS and the time constant of GABAA synaptic inhibition in gamma rhythmicity. However, the same theoretical models do not typically predict low-frequency LFP enhancement with RS drive. To develop hypotheses as to how the same network can support these contrasting behaviors, we constructed a biophysically principled network model of primary somatosensory neocortex containing FS, RS and low-threshold-spiking (LTS interneurons. Cells were modeled with detailed cell anatomy and physiology, multiple dendritic compartments, and included active somatic and dendritic ionic currents. Consistent with prior studies, the model demonstrated gamma resonance during FS drive, dependent on the time-constant of GABAA inhibition induced by synchronous FS activity. Lower frequency enhancement during RS drive was replicated only on inclusion of an inhibitory LTS population, whose activation was critically dependent on RS synchrony and evoked longer-lasting inhibition. Our results predict that differential recruitment of FS and LTS inhibitory populations is essential to the observed cortical dynamics and may provide a means for amplifying the natural expression of distinct oscillations in normal cortical processing.

  7. Early-life exposure to caffeine affects the construction and activity of cortical networks in mice.

    Science.gov (United States)

    Fazeli, Walid; Zappettini, Stefania; Marguet, Stephan Lawrence; Grendel, Jasper; Esclapez, Monique; Bernard, Christophe; Isbrandt, Dirk

    2017-09-01

    The consumption of psychoactive drugs during pregnancy can have deleterious effects on newborns. It remains unclear whether early-life exposure to caffeine, the most widely consumed psychoactive substance, alters brain development. We hypothesized that maternal caffeine ingestion during pregnancy and the early postnatal period in mice affects the construction and activity of cortical networks in offspring. To test this hypothesis, we focused on primary visual cortex (V1) as a model neocortical region. In a study design mimicking the daily consumption of approximately three cups of coffee during pregnancy in humans, caffeine was added to the drinking water of female mice and their offspring were compared to control offspring. Caffeine altered the construction of GABAergic neuronal networks in V1, as reflected by a reduced number of somatostatin-containing GABA neurons at postnatal days 6-7, with the remaining ones showing poorly developed dendritic arbors. These findings were accompanied by increased synaptic activity in vitro and elevated network activity in vivo in V1. Similarly, in vivo hippocampal network activity was altered from the neonatal period until adulthood. Finally, caffeine-exposed offspring showed increased seizure susceptibility in a hyperthermia-induced seizure model. In summary, our results indicate detrimental effects of developmental caffeine exposure on mouse brain development. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Gap junction networks can generate both ripple-like and fast ripple-like oscillations

    Science.gov (United States)

    Simon, Anna; Traub, Roger D.; Vladimirov, Nikita; Jenkins, Alistair; Nicholson, Claire; Whittaker, Roger G.; Schofield, Ian; Clowry, Gavin J.; Cunningham, Mark O.; Whittington, Miles A.

    2014-01-01

    Fast ripples (FRs) are network oscillations, defined variously as having frequencies of > 150 to > 250 Hz, with a controversial mechanism. FRs appear to indicate a propensity of cortical tissue to originate seizures. Here, we demonstrate field oscillations, at up to 400 Hz, in spontaneously epileptic human cortical tissue in vitro, and present a network model that could explain FRs themselves, and their relation to ‘ordinary’ (slower) ripples. We performed network simulations with model pyramidal neurons, having axons electrically coupled. Ripples ( 250 Hz, were sustained or interrupted, and had little jitter in the firing of individual axons. The form of model FR was similar to spontaneously occurring FRs in excised human epileptic tissue. In vitro, FRs were suppressed by a gap junction blocker. Our data suggest that a given network can produce ripples, FRs, or both, via gap junctions, and that FRs are favored by clusters of axonal gap junctions. If axonal gap junctions indeed occur in epileptic tissue, and are mediated by connexin 26 (recently shown to mediate coupling between immature neocortical pyramidal cells), then this prediction is testable. PMID:24118191

  9. Social networking services: technologies and applications

    OpenAIRE

    Puzyrnyy, Oleksandr

    2011-01-01

    Puzyrnyy, Oleksandr. 2011. Social networking services: technologies and applications. Bachelor's Thesis. Kemi-Tornio University of Applied Sciences. Business and Culture. Pages 52. The aim of this thesis is to describe the concept of social networking, its technological base, business opportunities and future perspectives. The study discovers how social networks are made and which different purposes they might have. In addition, social networking is viewed as a part of business strategy o...

  10. Collectivism as Potlatch in the Network Age

    OpenAIRE

    Iitaka, Toshikazu

    2012-01-01

    This paper is about collectivism in the network age. Many previous studies about network society consider collectivism to be an important factor for innovation in the network age. However, a few studies about seken focus on the negative effects of collectivism. Both approaches focus on the tradition of exchanging or giving gifts, called potlatch or gift culture, often observed in premodern communities. This tradition is considered a significant aspect for frequent networking, including inn...

  11. A Cultural Sexuality or a Sexual Culture?

    NARCIS (Netherlands)

    Vandermeersch, Patrick

    1990-01-01

    P. Vandermeersch, A Cultural Sexuality or a Sexual Culture? In: F. VAN DE VIJVER & G. HUTSCHEMAEKERS (ed.), The Investigation of Culture. Current Issues in Cultural Psychology, Tilburg, Tilburg University Press, 1990, 43-58.

  12. Taurine activates GABAergic networks in the neocortex of immature mice

    Directory of Open Access Journals (Sweden)

    Bogdan Aurel Sava

    2014-02-01

    Full Text Available Although it has been suggested that taurine is the main endogenous neurotransmitter acting on glycine receptors, the implications of glycine receptor-mediated taurine actions on immature neocortical networks have not been addressed yet. To investigate the influence of taurine on the excitability of neuronal networks in the immature neocortex, we performed whole-cell patch-clamp recordings from visually identified pyramidal neurons and interneurons in coronal slices from C57Bl/6 and GAD67-GFP transgenic mice (postnatal days 2-4. In 46 % of the pyramidal neurons bath-application of taurine at concentrations ≥ 300 mM significantly enhanced the frequency of postsynaptic currents (PSCs by 744.3 ± 93.8 % (n = 120 cells. This taurine-induced increase of PSC frequency was abolished by 0.2 mM tetrodotoxine, 1 mM strychnine or 3 mM gabazine, but was unaffected by the glutamatergic antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX and (± R(--3-(2-carboxypiperazine-4-yl-propyl-1-phosphonic acid (CPP, suggesting that taurine specifically activates GABAergic network activity projecting to pyramidal neurons. Cell-attached recordings revealed that taurine enhanced the frequency of action potentials in pyramidal neurons, indicating an excitatory action of the GABAergic PSCs. In order to identify the presynaptic targets of taurine we demonstrate that bath application of taurine induced in GAD67-GFP labeled interneurons an inward current that is mainly mediated by glycine receptors and can generate action potentials in these cells. We conclude from these results that taurine can enhance network excitability in the immature neocortex by selectively activating GABAergic interneurons via interactions with glycine receptors.

  13. Establishing a Statistical Link between Network Oscillations and Neural Synchrony.

    Directory of Open Access Journals (Sweden)

    Pengcheng Zhou

    2015-10-01

    Full Text Available Pairs of active neurons frequently fire action potentials or "spikes" nearly synchronously (i.e., within 5 ms of each other. This spike synchrony may occur by chance, based solely on the neurons' fluctuating firing patterns, or it may occur too frequently to be explicable by chance alone. When spike synchrony above chances levels is present, it may subserve computation for a specific cognitive process, or it could be an irrelevant byproduct of such computation. Either way, spike synchrony is a feature of neural data that should be explained. A point process regression framework has been developed previously for this purpose, using generalized linear models (GLMs. In this framework, the observed number of synchronous spikes is compared to the number predicted by chance under varying assumptions about the factors that affect each of the individual neuron's firing-rate functions. An important possible source of spike synchrony is network-wide oscillations, which may provide an essential mechanism of network information flow. To establish the statistical link between spike synchrony and network-wide oscillations, we have integrated oscillatory field potentials into our point process regression framework. We first extended a previously-published model of spike-field association and showed that we could recover phase relationships between oscillatory field potentials and firing rates. We then used this new framework to demonstrate the statistical relationship between oscillatory field potentials and spike synchrony in: 1 simulated neurons, 2 in vitro recordings of hippocampal CA1 pyramidal cells, and 3 in vivo recordings of neocortical V4 neurons. Our results provide a rigorous method for establishing a statistical link between network oscillations and neural synchrony.

  14. Telecommunication networks

    CERN Document Server

    Iannone, Eugenio

    2011-01-01

    Many argue that telecommunications network infrastructure is the most impressive and important technology ever developed. Analyzing the telecom market's constantly evolving trends, research directions, infrastructure, and vital needs, Telecommunication Networks responds with revolutionized engineering strategies to optimize network construction. Omnipresent in society, telecom networks integrate a wide range of technologies. These include quantum field theory for the study of optical amplifiers, software architectures for network control, abstract algebra required to design error correction co

  15. Cultural Resurrection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    "Who are we?Where are we from?"Humans have been pondering these questions since the day they first came into being.One of the ways we preserve memories of the past is through our cul- tural heritage that has been passed on from generation to genera- tion.Intangible cultural heritage,as well as tangible cultural her- itage,is essential to the continuity of human civilization. Since the United Nations Educational,Scientific and Cultural Organization(UNESCO)unveiled the Masterpieces of the Oral and Intangible Heritage of Humanity in 2001,China has had Kunqu opera,Guqin and its music,the art of Uygur Muqam of Xinjiang and the traditional Mongolian folk song Long Song added to UNESCO’s protection list.It is now one of the coun-

  16. Creative Network Communities in the Translocal Space of Digital Networks

    Directory of Open Access Journals (Sweden)

    Rasa Smite

    2013-01-01

    Full Text Available What should sociological research be in the age of Web 2.0? Considering that the task of “network sociology” is not only empirical research but also the interpretation of tendencies of the network culture, this research explores the rise of network communities within Eastern and Western Europe in the early Internet era. I coined the term creative networks to distinguish these early creative and social activities from today’s popular social networking. Thus I aimed to interpret the meaning of social action; the motivation of creative community actors, their main fields of activities and social organization forms; and the potential that these early developments contain for the future sustainability of networks. Data comprise interviews with networking experts and founders and members of various networks. Investigating respondents’ motivations for creating online networks and communities, and interpreting those terms, allows for comparing the creative networks of the 1990s with today’s social networks and for drawing conclusions.

  17. Japanese Shame Culture and American Guilt Culture

    Institute of Scientific and Technical Information of China (English)

    Lu Weijie

    2016-01-01

    Culture is an important factor contributing to the success of intercultural communication. In the east and west, there are many different cultures, among which Japanese shame culture and American guilt culture are two typical ones. Influenced by different cultures, these two countries have different characteristics, which reminds us that in intercultural communication culture should be paid much attention to.

  18. Ciberperiodismo, telefonía móvil y acciones culturales barriales en Medellín Digital journalism, mobil network and cultural actions in local neighborhood at Medellin

    Directory of Open Access Journals (Sweden)

    Blandón Gómez Hernando

    2010-07-01

    Full Text Available Este trabajo es un análisis del uso y apropiación de TIC por las comunidades populares de la ciudad y de la incidencia del ciberperiodismo en las organizaciones culturales barriales y de los gestores culturales de Medellín. Se realizaron encuestas a gestores culturales, directores de centros culturales y vecinos en los barrios Santa Cruz, la América, Buenos Aires, Santo Domingo y algunos de la comuna 10, en la ciudad de Medellín. Se analizaron portales culturales internacionales, nacionales y locales desde los criterios del periodismo electrónico o ciberperiodismo. Los resultados indican que en Medellín existe una brecha digital significativa en el uso y apropiación en TIC por parte de las organizaciones barriales, hecho que neutraliza la labor de las instituciones y gestores culturales por la falta de divulgación en el ámbito urbano. Esta aproximación se focaliza en los procesos de apropiación en TIC por parte de las instituciones culturales barriales, para crear un portal cultural interactivo e hipermedial, que permita incentivar una comunidad virtual, cuya plataforma sea la divulgación e interacción de las diversas propuestas y acciones culturales entre las organizaciones de los barrios de Medellín, a través de la telefonía móvil. This work carries out an analysis of the use and acquisition of Information and Communication Technologies (ICT and its impact on the exercise of digital journalism by arts institutions in local neighborhoods and arts managers in Medellín. For that goal, surveys were held among arts managers, directors of cultural centers and residents of the neighborhoods Santa Cruz, La América, Buenos Aires, Santo Domingo and some neighborhoods of Comuna 10 [a conglomerate of neighborhoods in the north-east of the city]. National and international arts portals were analysed based on the criteria of digital journalism. The results indicate the existence in Medellín of a significant digital gap in the use and

  19. Mayan Culture

    DEFF Research Database (Denmark)

    Hervik, Peter Bent

    1992-01-01

    The social categories « Maya » and « mestizo » habe been applied to denote the Yucatec Mayan people in Mexico. The A. examines the cluster of perceived attributes (schemata) evoked by the terms and how they relate to each other. He shows that there is an incongruency between them along the lines ...... of local and academic categorization, which is an implication of the different social spaces in which they arise. In spite of the incongruency and the cultural plurality evoked by their usage, the A. argues that the people of Yucatec share a single culture....

  20. Information cultures

    DEFF Research Database (Denmark)

    Skouvig, Laura

    2017-01-01

    The purpose of this article is to suggest a genealogy of the concept of information beyond the 20th century. The article discusses how the concept of information culture might provide a way of formulating such a genealogic strategy. The article approaches this purpose by providing a general...... narrative of premodern information cultures, examining works on early-modern scholars and 18th century savants and discussion of what seems to be a Foucauldian rupture in the conceptualization of information in 19th century England. The findings of the article are situated in the thinking that a genealogy...... of information would reveal that information had specific purposes in specific settings....

  1. Grindr Culture

    DEFF Research Database (Denmark)

    Shield, Andrew DJ

    2018-01-01

    This research note is based on ethnographic work in the greater Copenhagen area on the socio-sexual networking app Grindr and on interviews with twelve recent immigrants who use this platform. As an online space primarily for gay men, Grindr is a unique subculture in which to conduct research about...

  2. Temporal networks

    CERN Document Server

    Saramäki, Jari

    2013-01-01

    The concept of temporal networks is an extension of complex networks as a modeling framework to include information on when interactions between nodes happen. Many studies of the last decade examine how the static network structure affect dynamic systems on the network. In this traditional approach  the temporal aspects are pre-encoded in the dynamic system model. Temporal-network methods, on the other hand, lift the temporal information from the level of system dynamics to the mathematical representation of the contact network itself. This framework becomes particularly useful for cases where there is a lot of structure and heterogeneity both in the timings of interaction events and the network topology. The advantage compared to common static network approaches is the ability to design more accurate models in order to explain and predict large-scale dynamic phenomena (such as, e.g., epidemic outbreaks and other spreading phenomena). On the other hand, temporal network methods are mathematically and concept...

  3. Interconnected networks

    CERN Document Server

    2016-01-01

    This volume provides an introduction to and overview of the emerging field of interconnected networks which include multi layer or multiplex networks, as well as networks of networks. Such networks present structural and dynamical features quite different from those observed in isolated networks. The presence of links between different networks or layers of a network typically alters the way such interconnected networks behave – understanding the role of interconnecting links is therefore a crucial step towards a more accurate description of real-world systems. While examples of such dissimilar properties are becoming more abundant – for example regarding diffusion, robustness and competition – the root of such differences remains to be elucidated. Each chapter in this topical collection is self-contained and can be read on its own, thus making it also suitable as reference for experienced researchers wishing to focus on a particular topic.

  4. Hydroponic Culture

    Science.gov (United States)

    Steucek, G. L.; Yurkiewicz, W. J.

    1973-01-01

    Describes a hydroponic culture technique suitable for student exercises in biology. This technique of growing plants in nutrient solutions enhances plant growth, and is an excellent way to obtain intact plants with root systems free of soil or other particulate matter. (JR)

  5. Blood culture

    Science.gov (United States)

    ... There, it is placed in a special dish (culture). It is then watched to see if bacteria or other disease-causing germs grow. A gram stain may also ... any time the skin is broken) Alternative Names ... Charnot-Katsikas A. Specimen collection and handling for diagnosis of infectious diseases. In: McPherson RA, Pincus MR, eds. Henry's Clinical ...

  6. Cultural Usability

    DEFF Research Database (Denmark)

    Shi, Qingxin

    2007-01-01

    Culture has already played an important role in the global market. It not only affects products, but also impacts on usability evaluation methods. This project aims to examine in the established thinking aloud usability evaluation method (TA UEM), how does the evaluator build a supportive...

  7. Grindr Culture

    DEFF Research Database (Denmark)

    Shield, Andrew DJ

    2018-01-01

    intersections of sexuality with other socio-cultural categories such as race and migration background, but also gender and ability. I find that user experiences with exclusion and discrimination can be related to Grindr’s interface, such as its drop-down menus, the discourses circulated by Grindr users...

  8. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  9. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  10. La vocazione territoriale tra approccio sistemico e situazionista: analisi di una collaborazione culture driven tra aziende del made in Italy attraverso il caso del Contratto di Rete Polo Alta Moda Area Vestina / The territorial vocation between the “systemic” approach and the “situationist” approach: analysis of a culture-driven collaboration between Made-in-Italy firms. The case of the network contract of “Polo Alta Moda Area Vestina

    Directory of Open Access Journals (Sweden)

    Elena Cedrola

    2014-06-01

    view in literature, defined “unitary” or “systemic”. Both the viewpoints recognize the territory as a treasure chest of values and show the presence of different stakeholders. The main point of difference between the two views seems to be based on the territorial vocation. While recognizing both the presence of shared interests among the actors, the “situationist” vision does not recognize to vocation its “rationalizing power” as in the “systemic” vision. After a brief review of the literature on the issues of territory as a shared culture, network size and the territorial and extraterritorial network contract, the study of a network contract signed on June 8th 2010 between the companies making up the Polo Alta Moda Area Vestina will be introduced. Through the evidence emerging from some in-depth interviews, the dual role of Brioni as a territorial key player and leading company of the network will be investigated. The other actors of Polo Alta Moda will be then examined. The interviews have been conducted with the business managers of the most important enterprise belonging to the network agreement, Brioni Roman Style, the Development Manager for Fashion Industry at the Chamber of Commerce of Pescara and the Director of the Foundations participating to the contract.

  11. Contribution of Intrinsic Lactate to Maintenance of Seizure Activity in Neocortical Slices from Patients with Temporal Lobe Epilepsy and in Rat Entorhinal Cortex.

    Science.gov (United States)

    Angamo, Eskedar Ayele; ul Haq, Rizwan; Rösner, Jörg; Gabriel, Siegrun; Gerevich, Zoltán; Heinemann, Uwe; Kovács, Richard

    2017-08-23

    Neuronal lactate uptake supports energy metabolism associated with synaptic signaling and recovery of extracellular ion gradients following neuronal activation. Altered expression of the monocarboxylate transporters (MCT) in temporal lobe epilepsy (TLE) hampers lactate removal into the bloodstream. The resulting increase in parenchymal lactate levels might exert both, anti- and pro-ictogen effects, by causing acidosis and by supplementing energy metabolism, respectively. Hence, we assessed the contribution of lactate to the maintenance of transmembrane potassium gradients, synaptic signaling and pathological network activity in chronic epileptic human tissue. Stimulus induced and spontaneous field potentials and extracellular potassium concentration changes (∆[K⁺] O ) were recorded in parallel with tissue pO₂ and pH in slices from TLE patients while blocking MCTs by α-cyano-4-hydroxycinnamic acid (4-CIN) or d-lactate. Intrinsic lactate contributed to the oxidative energy metabolism in chronic epileptic tissue as revealed by the changes in pO₂ following blockade of lactate uptake. However, unlike the results in rat hippocampus, ∆[K⁺] O recovery kinetics and field potential amplitude did not depend on the presence of lactate. Remarkably, inhibition of lactate uptake exerted pH-independent anti-seizure effects both in healthy rat and chronic epileptic tissue and this effect was partly mediated via adenosine 1 receptor activation following decreased oxidative metabolism.

  12. Network workshop

    DEFF Research Database (Denmark)

    Bruun, Jesper; Evans, Robert Harry

    2014-01-01

    This paper describes the background for, realisation of and author reflections on a network workshop held at ESERA2013. As a new research area in science education, networks offer a unique opportunity to visualise and find patterns and relationships in complicated social or academic network data....... These include student relations and interactions and epistemic and linguistic networks of words, concepts and actions. Network methodology has already found use in science education research. However, while networks hold the potential for new insights, they have not yet found wide use in the science education...... research community. With this workshop, participants were offered a way into network science based on authentic educational research data. The workshop was constructed as an inquiry lesson with emphasis on user autonomy. Learning activities had participants choose to work with one of two cases of networks...

  13. Network Convergence

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Network Convergence. User is interested in application and content - not technical means of distribution. Boundaries between distribution channels fade out. Network convergence leads to seamless application and content solutions.

  14. Industrial Networks

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    Companies organize in a way that involves many activities that are external to the traditional organizational boundaries. This presents challenges to operations management and managing operations involves many issues and actions dealing with external networks. Taking a network perspective changes...

  15. Network Science

    National Research Council Canada - National Science Library

    Leland, Will

    2006-01-01

    OVERVIEW: (1) A committee of technical experts, military officers and R&D managers was assembled by the National Research Council to reach consensus on the nature of networks and network research. (2...

  16. Talking Culture

    DEFF Research Database (Denmark)

    Holmgreen, Lise-Lotte

    When Danish businesses move production abroad, ‘culture’ is often seen as a huge challenge to the successful outcome of cross-border collaboration. Therefore, business leaders often seek information and guidelines of how to cope in the vast amount of literature on culture and intercultural...... communication. Much of this literature is based on functionalist approaches providing the dos and don’ts of intercultural encounters. This involves inter alia conceptualising ‘culture’ as a relatively fixed, homogeneous entity of values, attitudes and norms shared by members of a group, often leading readers...... to adopt dichotomised understandings and discourses about other cultures (see e.g. Hofstede 2001; Jandt 1998; Trompenaars & Hampden-Turner 1997). However, experience shows that the world in which intercultural encounters take place is not as simple and easy to categorise as these approaches may suggest...

  17. MARKETING CULTURAL

    Directory of Open Access Journals (Sweden)

    Claudia Gómez Ramírez

    2013-07-01

    Full Text Available Este artículo analiza la definición de "Marketing" Cultural y la adaptación y beneficios del "marketing" tradicional respecto al conjunto de manifestaciones artísticas de las diversas industrias involucradas en el sector cultural o artístico; asimismo, se desagregan los conceptos básicos que lo componen como factor de éxito en dichas empresas. Se hace uso de la exposición de casos específicos para ilustrar la articulación de estos dos conceptos aparentemente contrapuestos, cultura y "marketing", y registra algunas reflexiones para que el lector se involucre en la construcción del concepto aquí presentado.

  18. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Roetter, Daniel Enrique Lucani

    2015-01-01

    Software Defined Networking (SDN) and Network Coding (NC) are two key concepts in networking that have garnered a large attention in recent years. On the one hand, SDN's potential to virtualize services in the Internet allows a large flexibility not only for routing data, but also to manage....... This paper advocates for the use of SDN to bring about future Internet and 5G network services by incorporating network coding (NC) functionalities. The inherent flexibility of both SDN and NC provides a fertile ground to envision more efficient, robust, and secure networking designs, that may also...

  19. Visual motion imagery neurofeedback based on the hMT+/V5 complex: evidence for a feedback-specific neural circuit involving neocortical and cerebellar regions

    Science.gov (United States)

    Banca, Paula; Sousa, Teresa; Catarina Duarte, Isabel; Castelo-Branco, Miguel

    2015-12-01

    Objective. Current approaches in neurofeedback/brain-computer interface research often focus on identifying, on a subject-by-subject basis, the neural regions that are best suited for self-driven modulation. It is known that the hMT+/V5 complex, an early visual cortical region, is recruited during explicit and implicit motion imagery, in addition to real motion perception. This study tests the feasibility of training healthy volunteers to regulate the level of activation in their hMT+/V5 complex using real-time fMRI neurofeedback and visual motion imagery strategies. Approach. We functionally localized the hMT+/V5 complex to further use as a target region for neurofeedback. An uniform strategy based on motion imagery was used to guide subjects to neuromodulate hMT+/V5. Main results. We found that 15/20 participants achieved successful neurofeedback. This modulation led to the recruitment of a specific network as further assessed by psychophysiological interaction analysis. This specific circuit, including hMT+/V5, putative V6 and medial cerebellum was activated for successful neurofeedback runs. The putamen and anterior insula were recruited for both successful and non-successful runs. Significance. Our findings indicate that hMT+/V5 is a region that can be modulated by focused imagery and that a specific cortico-cerebellar circuit is recruited during visual motion imagery leading to successful neurofeedback. These findings contribute to the debate on the relative potential of extrinsic (sensory) versus intrinsic (default-mode) brain regions in the clinical application of neurofeedback paradigms. This novel circuit might be a good target for future neurofeedback approaches that aim, for example, the training of focused attention in disorders such as ADHD.

  20. Intermittent Theta-Burst Transcranial Magnetic Stimulation Alters Electrical Properties of Fast-Spiking Neocortical Interneurons in an Age-Dependent Fashion

    Directory of Open Access Journals (Sweden)

    Kathrin eHoppenrath

    2016-03-01

    Full Text Available Modulation of human cortical excitability by repetitive transcranial magnetic stimulation (rTMS appears to be in part related to changed activity of inhibitory systems. Our own studies showed that intermittent theta-burst stimulation (iTBS applied via rTMS to rat cortex primarily affects the parvalbumin-expressing (PV fast-spiking interneurons (FSIs, evident via a strongly reduced PV expression. We further found the iTBS effect on PV to be age-dependent since no reduction in PV could be induced before the perineuronal nets (PNNs of FSIs start to grow around postnatal day 30. To elucidate possible iTBS-induced changes in the electrical properties of FSIs and cortical network activity during cortical critical period, we performed ex vivo – in vitro whole-cell patch clamp recordings from pre-labelled FSIs in the current study. FSIs of verum iTBS-treated rats displayed a higher excitability than sham-treated controls at PD29-38, evident as higher rates of induced action potential firing at low current injections (100-200 pA and a more depolarized resting membrane potential. This effect was absent in younger (PD26-28 and older animals (PD40-62. Slices of verum iTBS-treated rats further showed higher rates of spontaneous EPSCs. Based on these and previous findings we conclude that FSIs are particularly sensitive to theta-burst stimulation during early cortical development, when FSIs show an activity-driven step of maturation which is paralleled by intense growth of the PNNs and subsequent closure of the cortical critical period. Although to be proven further, rTMS may be a possible early intervention to compensate for hypo-activity related mal-development of cortical neuronal circuits.

  1. Intermittent Theta-Burst Transcranial Magnetic Stimulation Alters Electrical Properties of Fast-Spiking Neocortical Interneurons in an Age-Dependent Fashion.

    Science.gov (United States)

    Hoppenrath, Kathrin; Härtig, Wolfgang; Funke, Klaus

    2016-01-01

    Modulation of human cortical excitability by repetitive transcranial magnetic stimulation (rTMS) appears to be in part related to changed activity of inhibitory systems. Our own studies showed that intermittent theta-burst stimulation (iTBS) applied via rTMS to rat cortex primarily affects the parvalbumin-expressing (PV) fast-spiking interneurons (FSIs), evident via a strongly reduced PV expression. We further found the iTBS effect on PV to be age-dependent since no reduction in PV could be induced before the perineuronal nets (PNNs) of FSIs start to grow around postnatal day (PD) 30. To elucidate possible iTBS-induced changes in the electrical properties of FSIs and cortical network activity during cortical critical period, we performed ex vivo-in vitro whole-cell patch clamp recordings from pre-labeled FSIs in the current study. FSIs of verum iTBS-treated rats displayed a higher excitability than sham-treated controls at PD29-38, evident as higher rates of induced action potential firing at low current injections (100-200 pA) and a more depolarized resting membrane potential. This effect was absent in younger (PD26-28) and older animals (PD40-62). Slices of verum iTBS-treated rats further showed higher rates of spontaneous excitatory postsynaptic currents (sEPSCs). Based on these and previous findings we conclude that FSIs are particularly sensitive to TBS during early cortical development, when FSIs show an activity-driven step of maturation which is paralleled by intense growth of the PNNs and subsequent closure of the cortical critical period. Although to be proven further, rTMS may be a possible early intervention to compensate for hypo-activity related mal-development of cortical neuronal circuits.

  2. Network Simulation

    CERN Document Server

    Fujimoto, Richard

    2006-01-01

    "Network Simulation" presents a detailed introduction to the design, implementation, and use of network simulation tools. Discussion topics include the requirements and issues faced for simulator design and use in wired networks, wireless networks, distributed simulation environments, and fluid model abstractions. Several existing simulations are given as examples, with details regarding design decisions and why those decisions were made. Issues regarding performance and scalability are discussed in detail, describing how one can utilize distributed simulation methods to increase the

  3. Epileptogenic networks in nodular heterotopia: A stereoelectroencephalography study.

    Science.gov (United States)

    Pizzo, Francesca; Roehri, Nicolas; Catenoix, Hélène; Medina, Samuel; McGonigal, Aileen; Giusiano, Bernard; Carron, Romain; Scavarda, Didier; Ostrowsky, Karine; Lepine, Anne; Boulogne, Sébastien; Scholly, Julia; Hirsch, Edouard; Rheims, Sylvain; Bénar, Christian-George; Bartolomei, Fabrice

    2017-12-01

    Defining the roles of heterotopic and normotopic cortex in the epileptogenic networks in patients with nodular heterotopia is challenging. To elucidate this issue, we compared heterotopic and normotopic cortex using quantitative signal analysis on stereoelectroencephalography (SEEG) recordings. Clinically relevant biomarkers of epileptogenicity during ictal (epileptogenicity index; EI) and interictal recordings (high-frequency oscillation and spike) were evaluated in 19 patients undergoing SEEG. These biomarkers were then compared between heterotopic cortex and neocortical regions. Seizures were classified as normotopic, heterotopic, or normoheterotopic according to respective values of quantitative analysis (EI ≥0.3). A total of 1,246 contacts were analyzed: 259 in heterotopic tissue (heterotopic cortex), 873 in neocortex in the same lobe of the lesion (local neocortex), and 114 in neocortex distant from the lesion (distant neocortex). No significant difference in EI values, high-frequency oscillations, and spike rate was found comparing local neocortex and heterotopic cortex at a patient level, but local neocortex appears more epileptogenic (p < 0.001) than heterotopic cortex analyzing EI values at a seizure level. According to EI values, seizures were mostly normotopic (48.5%) or normoheterotopic (45.5%); only 6% were purely heterotopic. A good long-term treatment response was obtained in only two patients after thermocoagulation and surgical disconnection. This is the first quantitative SEEG study providing insight into the mechanisms generating seizures in nodular heterotopia. We demonstrate that both the heterotopic lesion and particularly the normotopic cortex are involved in the epileptogenic network. This could open new perspectives on multitarget treatments, other than resective surgery, aimed at modifying the epileptic network. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  4. Acupuncture, the limbic system, and the anticorrelated networks of the brain.

    Science.gov (United States)

    Hui, Kathleen K S; Marina, Ovidiu; Liu, Jing; Rosen, Bruce R; Kwong, Kenneth K

    2010-10-28

    The study of the mechanism of acupuncture action was revolutionized by the use of functional magnetic resonance imaging (fMRI). Over the past decade, our fMRI studies of healthy subjects have contributed substantially to elucidating the central effect of acupuncture on the human brain. These studies have shown that acupuncture stimulation, when associated with sensations comprising deqi, evokes deactivation of a limbic-paralimbic-neocortical network, which encompasses the limbic system, as well as activation of somatosensory brain regions. These networks closely match the default mode network and the anti-correlated task-positive network described in the literature. We have also shown that the effect of acupuncture on the brain is integrated at multiple levels, down to the brainstem and cerebellum. Our studies support the hypothesis that the effect of acupuncture on the brain goes beyond the effect of attention on the default mode network or the somatosensory stimulation of acupuncture needling. The amygdala and hypothalamus, in particular, show decreased activation during acupuncture stimulation that is not commonly associated with default mode network activity. At the same time, our research shows that acupuncture stimulation needs to be done carefully, limiting stimulation when the resulting sensations are very strong or when sharp pain is elicited. When acupuncture induced sharp pain, our studies show that the deactivation was attenuated or reversed in direction. Our results suggest that acupuncture mobilizes the functionally anti-correlated networks of the brain to mediate its actions, and that the effect is dependent on the psychophysical response. In this work we also discuss multiple avenues of future research, including the role of neurotransmitters, the effect of different acupuncture techniques, and the potential clinical application of our research findings to disease states including chronic pain, major depression, schizophrenia, autism, and Alzheimer

  5. Cultural Robotics: The Culture of Robotics and Robotics in Culture

    Directory of Open Access Journals (Sweden)

    Hooman Samani

    2013-12-01

    Full Text Available In this paper, we have investigated the concept of “Cultural Robotics” with regard to the evolution of social into cultural robots in the 21st Century. By defining the concept of culture, the potential development of a culture between humans and robots is explored. Based on the cultural values of the robotics developers, and the learning ability of current robots, cultural attributes in this regard are in the process of being formed, which would define the new concept of cultural robotics. According to the importance of the embodiment of robots in the sense of presence, the influence of robots in communication culture is anticipated. The sustainability of robotics culture based on diversity for cultural communities for various acceptance modalities is explored in order to anticipate the creation of different attributes of culture between robots and humans in the future.

  6. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimise the management of the Technical Network (TN), to facilitate understanding of the purpose of devices connected to the TN and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive e-mails from IT/CS asking them to add the corresponding information in the network database at "network-cern-ch". Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  7. La arquitectura cultural. / Cultural architecture.

    Directory of Open Access Journals (Sweden)

    Lobos, Jorge

    2004-12-01

    Full Text Available Este artículo releva la Arquitectura Cultural, que es plural y diversa en términos estéticos y conceptuales. Sugiere la apertura a otras dinámicas de comprensión de lo arquitectónico, a otras lógicas de construcción de las ciudades. Para aclarar el concepto se expone un breve ejemplo práctico./This article points out the "cultural architecture", which is plural and diverse in concept and aesthetic terms. It suggests the opening to other dinamics of comprehention of the architectural issue and the building of cities. The article presents a brief empirical example that clarifies the conceptual approach.

  8. Spatial networks

    Science.gov (United States)

    Barthélemy, Marc

    2011-02-01

    Complex systems are very often organized under the form of networks where nodes and edges are embedded in space. Transportation and mobility networks, Internet, mobile phone networks, power grids, social and contact networks, and neural networks, are all examples where space is relevant and where topology alone does not contain all the information. Characterizing and understanding the structure and the evolution of spatial networks is thus crucial for many different fields, ranging from urbanism to epidemiology. An important consequence of space on networks is that there is a cost associated with the length of edges which in turn has dramatic effects on the topological structure of these networks. We will thoroughly explain the current state of our understanding of how the spatial constraints affect the structure and properties of these networks. We will review the most recent empirical observations and the most important models of spatial networks. We will also discuss various processes which take place on these spatial networks, such as phase transitions, random walks, synchronization, navigation, resilience, and disease spread.

  9. Network science

    CERN Document Server

    Barabasi, Albert-Laszlo

    2016-01-01

    Networks are everywhere, from the Internet, to social networks, and the genetic networks that determine our biological existence. Illustrated throughout in full colour, this pioneering textbook, spanning a wide range of topics from physics to computer science, engineering, economics and the social sciences, introduces network science to an interdisciplinary audience. From the origins of the six degrees of separation to explaining why networks are robust to random failures, the author explores how viruses like Ebola and H1N1 spread, and why it is that our friends have more friends than we do. Using numerous real-world examples, this innovatively designed text includes clear delineation between undergraduate and graduate level material. The mathematical formulas and derivations are included within Advanced Topics sections, enabling use at a range of levels. Extensive online resources, including films and software for network analysis, make this a multifaceted companion for anyone with an interest in network sci...

  10. Vulnerability of network of networks

    Science.gov (United States)

    Havlin, S.; Kenett, D. Y.; Bashan, A.; Gao, J.; Stanley, H. E.

    2014-10-01

    Our dependence on networks - be they infrastructure, economic, social or others - leaves us prone to crises caused by the vulnerabilities of these networks. There is a great need to develop new methods to protect infrastructure networks and prevent cascade of failures (especially in cases of coupled networks). Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How, and at which cost can one restructure the network such that it will become more robust against malicious attacks? The gradual increase in attacks on the networks society depends on - Internet, mobile phone, transportation, air travel, banking, etc. - emphasize the need to develop new strategies to protect and defend these crucial networks of communication and infrastructure networks. One example is the threat of liquid explosives a few years ago, which completely shut down air travel for days, and has created extreme changes in regulations. Such threats and dangers warrant the need for new tools and strategies to defend critical infrastructure. In this paper we review recent advances in the theoretical understanding of the vulnerabilities of interdependent networks with and without spatial embedding, attack strategies and their affect on such networks of networks as well as recently developed strategies to optimize and repair failures caused by such attacks.

  11. Cultural Robotics: The Culture of Robotics and Robotics in Culture

    OpenAIRE

    Hooman Samani; Elham Saadatian; Natalie Pang; Doros Polydorou; Owen Noel Newton Fernando; Ryohei Nakatsu; Jeffrey Tzu Kwan Valino Koh

    2013-01-01

    In this paper, we have investigated the concept of “Cultural Robotics” with regard to the evolution of social into cultural robots in the 21st Century. By defining the concept of culture, the potential development of a culture between humans and robots is explored. Based on the cultural values of the robotics developers, and the learning ability of current robots, cultural attributes in this regard are in the process of being formed, which would define the new concept of cultural robotics. Ac...

  12. Black Culture

    Directory of Open Access Journals (Sweden)

    Angela Khristin Brown

    2013-07-01

    Full Text Available The migration of blacks in North America through slavery became united.  The population of blacks past downs a tradition of artist through art to native born citizens. The art tradition involved telling stories to each generation in black families. The black culture elevated by tradition created hope to determine their personal freedom to escape from poverty of enslavement and to establish a way of life through tradition. A way of personal freedoms was through getting a good education that lead to a better foundation and a better way of life.

  13. Culture Jamming Versus Popular Culture

    Directory of Open Access Journals (Sweden)

    Leonardia Acynthia Putri

    2013-11-01

    Full Text Available Abstract: This literature study researched Adbusters, the anti-commercial organization, and described the organization’s activities and media usage, mainly in the period of 2007-2010, which critized the populer culture. Adbusters is an organization which performs “Culture Jamming”; a rebellious act reacting towards commercialism domination in many aspects including popular culture. Compared to other similar organizations, Adbusters has been executing more various activisms using several media which other organizations do not use. This study used the Adbusters’ official website and blogs as main data sources. The data of Adbusters’ activities and media usage were categorized and analyzed, thus the tendency of its development can be described. This study also analyzed Adbusters’ activity using Media Hegemony Theory and Political Economy Media Theory. The media has been dominated by a certain group that owns politic and economic power, so the information flow has been dominated by them. Media and its contents have been commercialized, thus capitalism and commercialism have been considered as a common system that should run the world. Adbusters has been trying to stop the domination and change the society’s way of thinking into a more critical way of thinking.   Abstrak: Studi literatur ini meneliti tentang Adbusters, sebuah organisasi anti komersial, dengan mendeskripsikan aktivitas serta penggunaan media organisasi tersebut dari tahun 2007-2010 dalam mengkritisi budaya populer. Adbusters adalah organisasi yang melakukan Culture Jamming, aksi perlawanan terhadap dominasi komersialisme di segala aspek termasuk popular culture. Dibandingkan dengan organisasi lain yang serupa, aktivitas Adbusters lebih bervariasi dan menggunakan media-media yang tidak biasa digunakan organisasi lain. Penelitian ini menggunakan situs online resmi Adbusters sebagai sumber data utama. Data mengenai aktivitas dan

  14. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Hansen, Jonas; Roetter, Daniel Enrique Lucani; Krigslund, Jeppe

    2015-01-01

    Software defined networking has garnered large attention due to its potential to virtualize services in the Internet, introducing flexibility in the buffering, scheduling, processing, and routing of data in network routers. SDN breaks the deadlock that has kept Internet network protocols stagnant...... for decades, while applications and physical links have evolved. This article advocates for the use of SDN to bring about 5G network services by incorporating network coding (NC) functionalities. The latter constitutes a major leap forward compared to the state-of-the- art store and forward Internet paradigm...

  15. Technological Transformations of Reading Culture

    DEFF Research Database (Denmark)

    Albrechtslund, Anne-Mette Bech

    The increasing use of social media along with the rapidly developing digitization of the book has led to a range of new circumstances for writing, publishing and reading books, resulting in transformations in reading culture and practices. The social aspect of reading is emphasized when readers...... relations in the network of writers, publishers, readers, and reviewers. Similarly, the increasing use of electronic reading devices plays a key role in the acceleration of a culture in which the audience engages with cultural works in new ways. The print book has an “easy materiality” (Marshall, 2010, p....... 17), but with the electronic book, the materiality of reading becomes more ambiguous and malleable as the book as technology is being radically reconstructed. The purpose of this paper is to explore these changes through an investigation into the technology relations (Ihde, 1990) in fiction reading...

  16. Culture collections.

    Science.gov (United States)

    Smith, David

    2012-01-01

    Culture collections no matter their size, form, or institutional objectives play a role in underpinning microbiology, supplying the resources for study, innovation, and discovery. Their basic roles include providing a mechanism for ex situ conservation of organisms; they are repositories for strains subject to publication, taking in safe, confidential, and patent deposits from researchers. They supply strains for use; therefore, the microorganisms provided must be authentic and preserved well, and any associated information must be valid and sufficient to facilitate the confirmation of their identity and to facilitate their use. The organisms must be collected in compliance with international conventions, international and national legislation and distributed to users indicating clearly the terms and conditions under which they are received and can be used. Collections are harmonizing approaches and characterizing strains to meet user needs. No one single collection can carry out this task alone, and therefore, it is important that output and strategy are coordinated to ensure culture collections deliver the basic resources and services microbiological innovation requires. This chapter describes the types of collection and how they can implement quality management systems and operate to deliver their basic functions. The links to information sources given not only provide support for the practitioners within collections but also provide guidance to users on accessing the huge resource available and how they can help ensure microbiology has the resources and a solid platform for future development. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. PERSON IN SOCIAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Андрей Борисович Шалимов

    2013-11-01

    Full Text Available Purpose: Our scientific purpose is creation of practical model of person’s representation in social networks (Facebook, Twitter, Classmates. As user of social networks, person is made conditional not only upon its own identity, but also upon the information about himself, which he is ready to share with his friends in contact list. Goal-setting and practical activities for their achievement mean that you should apply force, it can completely eliminates systemic factors, the system of power relations, which overwhelms human being in social networks.Methodology: The reconstruction of the model of human in the popularity of social networksResults: There is descripton of practical model of person's representation in social networks, it includes the management of own identity and the audience (the list of contacts. When person manages own identity, he answers the question, «Whom I can dare to be?». Person perceives himself in social networks' being, he understands himself and his place in the world, he identifies.Managing the way in social media means that you answer the question «What I want to tell?». Person in social media looks at events in the field of culture, economy, politics, social relations through the prism of his own attitudes, he forms and formulates his own agenda and he is going to tell about himself through them.Practical implications: Everyday people’s life, practical activities, including marketing in social networks.DOI: http://dx.doi.org/10.12731/2218-7405-2013-9-51

  18. Social Networks and Political Parties in Chile

    OpenAIRE

    Adler Lomnitz, Larissa

    2002-01-01

    This paper describes the origin and evolution of two Chilean political parties (the Radical Party and the Christian Democrat Party) through the analysis of the social networks that originated and composed them. The aim of this study is to propose a model of national political cultures on the basis of the structure of social networks related to power and of the symbol system, which legitimizes it. The structure of social networks, horizontal and vertical, are based on reciprocal or redistribut...

  19. The Strategic Paradox of Social Networks

    Science.gov (United States)

    2011-03-18

    United States claimed to have met online.9 And in 2010, Facebook claimed over 500 million users, which would make the social networking service the...service culture, or occupational specialty. One drawback with social networks concerns the protection of individual privacy. Facebook , for...St ra te gy R es ea rc h Pr oj ec t THE STRATEGIC PARADOX OF SOCIAL NETWORKS BY COLONEL ROBERT COTE United States Marine Corps

  20. Networked Identities

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Larsen, Malene Charlotte

    2008-01-01

    of CoPs we shall argue that the metaphor or theory of networked learning is itself confronted with some central tensions and challenges that need to be addressed. We then explore these theoretical and analytic challenges to the network metaphor, through an analysis of a Danish social networking site. We......In this article we take up a critique of the concept of Communities of Practice (CoP) voiced by several authors, who suggest that networks may provide a better metaphor to understand social forms of organisation and learning. Through a discussion of the notion of networked learning and the critique...... argue that understanding meaning-making and ‘networked identities’ may be relevant analytic entry points in navigating the challenges....

  1. Ties that Bind: Cultural Referent Groups and Coping Strategies of Adult Women as Learners

    Science.gov (United States)

    Nanton, Carmela R.

    2009-01-01

    This chapter examines the cultural influences and applications of women's social capital networks on women's knowledge construction, community development, and autonomy within their cultures and the adult learning context.

  2. Hispanic Culture and Relational Cultural Theory

    Science.gov (United States)

    Ruiz, Elizabeth

    2005-01-01

    Traditional personality theories do not consider the impact of culture on personality development. Yet, to provide culturally relevant services to the increasing Hispanic population in the U.S., more culturally relevant theories must be identified. This paper presents Relational Cultural Theory (RCT) as an alternative model to understanding…

  3. Academic Culture and Campus Culture of Universities

    Science.gov (United States)

    Shen, Xi; Tian, Xianghong

    2012-01-01

    Academic culture of universities mainly consists of academic outlooks, academic spirits, academic ethics and academic environments. Campus culture in a university is characterized by individuality, academic feature, opening, leading, variety and creativity. The academic culture enhances the construction of campus culture. The campus culture…

  4. Culture-lovers and Culture-leavers

    NARCIS (Netherlands)

    Frank Huysmans; Andries van den Broek; Jos de Haan

    2005-01-01

    Who are the people in the Netherlands with an active interest in cultural heritage and the performing arts, and who prefer to leave these forms of culture alone? Have the size and composition of the groups of 'culture-lovers' and 'culture-leavers' changed since the end of the 1970s? These are the

  5. Network security

    CERN Document Server

    Perez, André

    2014-01-01

    This book introduces the security mechanisms deployed in Ethernet, Wireless-Fidelity (Wi-Fi), Internet Protocol (IP) and MultiProtocol Label Switching (MPLS) networks. These mechanisms are grouped throughout the book according to the following four functions: data protection, access control, network isolation, and data monitoring. Data protection is supplied by data confidentiality and integrity control services. Access control is provided by a third-party authentication service. Network isolation is supplied by the Virtual Private Network (VPN) service. Data monitoring consists of applying

  6. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago V. V.; Giannitsarou, Chryssi; Johnson, Charles R.

    2016-01-01

    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00199-016-0992-1 We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and d...

  7. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimize the management of the Technical Network (TN), to ease the understanding and purpose of devices connected to the TN, and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive email notifications from IT/CS asking them to add the corresponding information in the network database. Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  8. Social networks in primates: smart and tolerant species have more efficient networks.

    Science.gov (United States)

    Pasquaretta, Cristian; Levé, Marine; Claidière, Nicolas; van de Waal, Erica; Whiten, Andrew; MacIntosh, Andrew J J; Pelé, Marie; Bergstrom, Mackenzie L; Borgeaud, Christèle; Brosnan, Sarah F; Crofoot, Margaret C; Fedigan, Linda M; Fichtel, Claudia; Hopper, Lydia M; Mareno, Mary Catherine; Petit, Odile; Schnoell, Anna Viktoria; di Sorrentino, Eugenia Polizzi; Thierry, Bernard; Tiddi, Barbara; Sueur, Cédric

    2014-12-23

    Network optimality has been described in genes, proteins and human communicative networks. In the latter, optimality leads to the efficient transmission of information with a minimum number of connections. Whilst studies show that differences in centrality exist in animal networks with central individuals having higher fitness, network efficiency has never been studied in animal groups. Here we studied 78 groups of primates (24 species). We found that group size and neocortex ratio were correlated with network efficiency. Centralisation (whether several individuals are central in the group) and modularity (how a group is clustered) had opposing effects on network efficiency, showing that tolerant species have more efficient networks. Such network properties affecting individual fitness could be shaped by natural selection. Our results are in accordance with the social brain and cultural intelligence hypotheses, which suggest that the importance of network efficiency and information flow through social learning relates to cognitive abilities.

  9. Social networks in primates: smart and tolerant species have more efficient networks

    Science.gov (United States)

    Pasquaretta, Cristian; Levé, Marine; Claidière, Nicolas; van de Waal, Erica; Whiten, Andrew; MacIntosh, Andrew J. J.; Pelé, Marie; Bergstrom, Mackenzie L.; Borgeaud, Christèle; Brosnan, Sarah F.; Crofoot, Margaret C.; Fedigan, Linda M.; Fichtel, Claudia; Hopper, Lydia M.; Mareno, Mary Catherine; Petit, Odile; Schnoell, Anna Viktoria; di Sorrentino, Eugenia Polizzi; Thierry, Bernard; Tiddi, Barbara; Sueur, Cédric

    2014-01-01

    Network optimality has been described in genes, proteins and human communicative networks. In the latter, optimality leads to the efficient transmission of information with a minimum number of connections. Whilst studies show that differences in centrality exist in animal networks with central individuals having higher fitness, network efficiency has never been studied in animal groups. Here we studied 78 groups of primates (24 species). We found that group size and neocortex ratio were correlated with network efficiency. Centralisation (whether several individuals are central in the group) and modularity (how a group is clustered) had opposing effects on network efficiency, showing that tolerant species have more efficient networks. Such network properties affecting individual fitness could be shaped by natural selection. Our results are in accordance with the social brain and cultural intelligence hypotheses, which suggest that the importance of network efficiency and information flow through social learning relates to cognitive abilities. PMID:25534964

  10. FROM CULTURAL IMPOTENCE TO CULTURAL AMPUTATION

    Directory of Open Access Journals (Sweden)

    Sukhanov Vyacheslav Vladimirovich

    2013-02-01

    Full Text Available Cultural space of any state is formed by a population that is within its borders. In this article, the author introduces a new cultural definitions «cultural impotence» and «cultural amputation», justifying their use, both in terms of population of the Russian Federation and the European Union and America. The article analyzes the state of society and the cultural factors that influence the development of society in Russia, there are options to bring the country out of a deep cultural crisis. Also established a close relationship between the domestic policy of the state and development of culture.

  11. Cross-cultural and site-based influences on demographic, well-being, and social network predictors of risk perception in hazard and disaster settings in Ecuador and Mexico: predictors of risk perception in hazard and disaster settings in Ecuador and Mexico.

    Science.gov (United States)

    Jones, Eric C; Faas, Albert J; Murphy, Arthur D; Tobin, Graham A; Whiteford, Linda M; McCarty, Christopher

    2013-03-01

    Although virtually all comparative research about risk perception focuses on which hazards are of concern to people in different culture groups, much can be gained by focusing on predictors of levels of risk perception in various countries and places. In this case, we examine standard and novel predictors of risk perception in seven sites among communities affected by a flood in Mexico (one site) and volcanic eruptions in Mexico (one site) and Ecuador (five sites). We conducted more than 450 interviews with questions about how people feel at the time (after the disaster) regarding what happened in the past, their current concerns, and their expectations for the future. We explore how aspects of the context in which people live have an effect on how strongly people perceive natural hazards in relationship with demographic, well-being, and social network factors. Generally, our research indicates that levels of risk perception for past, present, and future aspects of a specific hazard are similar across these two countries and seven sites. However, these contexts produced different predictors of risk perception-in other words, there was little overlap between sites in the variables that predicted the past, present, or future aspects of risk perception in each site. Generally, current stress was related to perception of past danger of an event in the Mexican sites, but not in Ecuador; network variables were mainly important for perception of past danger (rather than future or present danger), although specific network correlates varied from site to site across the countries.

  12. Cultural Competence and the Operational Commander: Moving Beyond Cultural Awareness into Culture-Centric Warfare

    National Research Council Canada - National Science Library

    Karcanes, James A

    2007-01-01

    .... Understanding the different levels of cultural awareness -- cultural consideration, cultural understanding, and cultural competence -- will help usher in a new focus on culture-centric warfare...

  13. Overlay networks toward information networking

    CERN Document Server

    Tarkoma, Sasu

    2010-01-01

    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  14. INFLUENCES ON AND FROM THE SEGMENTATION OF NETWORKS - HYPOTHESES AND TESTS

    NARCIS (Netherlands)

    BAERVELDT, C; SNIJDERS, T

    This article discusses (a) the influence of network structure on the diffusion of (new) cultural behavior within the network and (b) the influence of external events, especially of social programs, on the diffusion of (new) cultural behavior, and on the network structure. Hypotheses are formulated

  15. Probabilistic Networks

    DEFF Research Database (Denmark)

    Jensen, Finn Verner; Lauritzen, Steffen Lilholt

    2001-01-01

    This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs.......This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs....

  16. Bipartite Networks

    NARCIS (Netherlands)

    Agneessens, F.; Moser, C.; Barnett, G.A.

    2011-01-01

    Bipartite networks refer to a specific kind of network in which the nodes (or actors) can be partitioned into two subsets based on the fact that no links exist between actors within each subset, but only between the two subsets. Due to the partition of actors in two sets and the absence of relations

  17. Fabrication and Operation of Microfluidic Hanging-Drop Networks.

    Science.gov (United States)

    Misun, Patrick M; Birchler, Axel K; Lang, Moritz; Hierlemann, Andreas; Frey, Olivier

    2018-01-01

    The hanging-drop network (HDN) is a technology platform based on a completely open microfluidic network at the bottom of an inverted, surface-patterned substrate. The platform is predominantly used for the formation, culturing, and interaction of self-assembled spherical microtissues (spheroids) under precisely controlled flow conditions. Here, we describe design, fabrication, and operation of microfluidic hanging-drop networks.

  18. Networks around Iranian entrepreneurs at home and in diaspora

    DEFF Research Database (Denmark)

    Cheraghi, Maryam; Yaghmaei, Emad

    2017-01-01

    Entrepreneurs rely on different types of networks like public and private. One reason for this difference between networks is a difference between cultures. Moreover, networking in public and private spheres has different consequences for entrepreneurial outcomes. The purpose of this study is to ...

  19. Temporal networks

    Science.gov (United States)

    Holme, Petter; Saramäki, Jari

    2012-10-01

    A great variety of systems in nature, society and technology-from the web of sexual contacts to the Internet, from the nervous system to power grids-can be modeled as graphs of vertices coupled by edges. The network structure, describing how the graph is wired, helps us understand, predict and optimize the behavior of dynamical systems. In many cases, however, the edges are not continuously active. As an example, in networks of communication via e-mail, text messages, or phone calls, edges represent sequences of instantaneous or practically instantaneous contacts. In some cases, edges are active for non-negligible periods of time: e.g., the proximity patterns of inpatients at hospitals can be represented by a graph where an edge between two individuals is on throughout the time they are at the same ward. Like network topology, the temporal structure of edge activations can affect dynamics of systems interacting through the network, from disease contagion on the network of patients to information diffusion over an e-mail network. In this review, we present the emergent field of temporal networks, and discuss methods for analyzing topological and temporal structure and models for elucidating their relation to the behavior of dynamical systems. In the light of traditional network theory, one can see this framework as moving the information of when things happen from the dynamical system on the network, to the network itself. Since fundamental properties, such as the transitivity of edges, do not necessarily hold in temporal networks, many of these methods need to be quite different from those for static networks. The study of temporal networks is very interdisciplinary in nature. Reflecting this, even the object of study has many names-temporal graphs, evolving graphs, time-varying graphs, time-aggregated graphs, time-stamped graphs, dynamic networks, dynamic graphs, dynamical graphs, and so on. This review covers different fields where temporal graphs are considered

  20. Network Affordances

    DEFF Research Database (Denmark)

    Samson, Audrey; Soon, Winnie

    2015-01-01

    This paper examines the notion of network affordance within the context of network art. Building on Gibson's theory (Gibson, 1979) we understand affordance as the perceived and actual parameters of a thing. We expand on Gaver's affordance of predictability (Gaver, 1996) to include ecological...... and computational parameters of unpredictability. We illustrate the notion of unpredictability by considering four specific works that were included in a network art exhibiton, SPEED SHOW [2.0] Hong Kong. The paper discusses how the artworks are contingent upon the parameteric relations (Parisi, 2013......), of the network. We introduce network affordance as a dynamic framework that could articulate the experienced tension arising from the (visible) symbolic representation of computational processes and its hidden occurrences. We base our proposal on the experience of both organising the SPEED SHOW and participating...

  1. Network chemistry, network toxicology, network informatics, and network behavioristics: A scientific outline

    OpenAIRE

    WenJun Zhang

    2016-01-01

    In present study, I proposed some new sciences: network chemistry, network toxicology, network informatics, and network behavioristics. The aims, scope and scientific foundation of these sciences are outlined.

  2. Serious Games Network

    Directory of Open Access Journals (Sweden)

    Carlos Vaz de Carvalho

    2013-11-01

    Full Text Available “Serious games” can be defined as (digital games used for purposes other than mere entertainment. Serious Games can be applied to a broad spectrum of areas, e.g. educational, healthcare, training in hazardous environments or situations. Game-based Learning, one aspect of Serious Games, are also more and more explored for all levels of education in different subjects, such as Ancient History. The SEGAN (SErious GAmes Network will create a Community of Practice on the Serious Games subject. The main objective is to create a stable (but expanding consortium to exchange ideas and experiences related to Serious Games. The SEGAN Network invites the people of the community of Archaeology, Cultural Heritage and Ancient History interested in Serious Games to join the net and to participate in their activities.

  3. Transnational Cultural Leadership as a Situated Practice : Dilemmas and Methods

    NARCIS (Netherlands)

    Kolsteeg, Johan

    2017-01-01

    In a longitudinal transnational research project, a network of European research institutions and field organisations aims to understand how cultural managers mediate global and local pressures concerning creative autonomy, economy and ideology. Among the research questions are which variables

  4. On Cultural And Academic Exchanges Between China And African ...

    African Journals Online (AJOL)

    ahavugimana

    Rwanda Journal, Series B: Social Sciences, Volume 2 No 1, 2015. Rwanda Journal ISSN .... setting up an African network or forum of research institutions and think- .... culture or ways of life is increasing in the public sphere. To take some.

  5. CONNECTION BETWEEN ECONOMICS, CULTURE AND CULTURAL DIPLOMACY

    Directory of Open Access Journals (Sweden)

    Agil Valiyev

    2017-09-01

    Full Text Available Today, culture is one of the main feeble factors of economic development.  The leading role of culture in economic development should be argued as multiplied: so, on firstly, as domestic value, on secondly, as a main factor of regional economic development advanced to raised gravity of different regions for residents, tourists and investors, on thirdly, as major parameters of social development based on tolerance, creativity and knowledge. To the different international experiences, culture is main part of economic development in our life. Cultural diversities are combined into a main reason economic development model. The article consist of explainations about the understanding of culture, cultural diplomacy and economics, approach on conflicts between culture and economics, to find how affecting of culture to economic development, the role of culture in economic development of Azerbaijan. The article can be considered as a useful resource  for experts and researchers conducting research in this field.

  6. Cultural Humility and Hospital Safety Culture.

    Science.gov (United States)

    Hook, Joshua N; Boan, David; Davis, Don E; Aten, Jamie D; Ruiz, John M; Maryon, Thomas

    2016-12-01

    Hospital safety culture is an integral part of providing high quality care for patients, as well as promoting a safe and healthy environment for healthcare workers. In this article, we explore the extent to which cultural humility, which involves openness to cultural diverse individuals and groups, is related to hospital safety culture. A sample of 2011 hospital employees from four hospitals completed measures of organizational cultural humility and hospital safety culture. Higher perceptions of organizational cultural humility were associated with higher levels of general perceptions of hospital safety, as well as more positive ratings on non-punitive response to error (i.e., mistakes of staff are not held against them), handoffs and transitions, and organizational learning. The cultural humility of one's organization may be an important factor to help improve hospital safety culture. We conclude by discussing potential directions for future research.

  7. Accelerating networks

    International Nuclear Information System (INIS)

    Smith, David M D; Onnela, Jukka-Pekka; Johnson, Neil F

    2007-01-01

    Evolving out-of-equilibrium networks have been under intense scrutiny recently. In many real-world settings the number of links added per new node is not constant but depends on the time at which the node is introduced in the system. This simple idea gives rise to the concept of accelerating networks, for which we review an existing definition and-after finding it somewhat constrictive-offer a new definition. The new definition provided here views network acceleration as a time dependent property of a given system as opposed to being a property of the specific algorithm applied to grow the network. The definition also covers both unweighted and weighted networks. As time-stamped network data becomes increasingly available, the proposed measures may be easily applied to such empirical datasets. As a simple case study we apply the concepts to study the evolution of three different instances of Wikipedia, namely, those in English, German, and Japanese, and find that the networks undergo different acceleration regimes in their evolution

  8. Recapitulating cortical development with organoid culture in vitro and modeling abnormal spindle-like (ASPM related primary) microcephaly disease

    Institute of Scientific and Technical Information of China (English)

    Rui Li; Le Sun; Ai Fang; Peng Li; Qian Wu; Xiaoqun Wang

    2017-01-01

    The development of a cerebral organoid culture in vitro offers an opportunity to generate human brain-like organs to investigate mechanisms of human disease that are specific to the neurogenesis of radial glial (RG) and outer radial glial (oRG) cells in the ventricular zone (VZ) and subventricular zone (SVZ) of the developing neocortex.Modeling neuronal progenitors and the organization that produces mature subcortical neuron subtypes during early stages of development is essential for studying human brain developmental diseases.Several previous efforts have shown to grow neural organoid in culture dishes successfully,however we demonstrate a new paradigm that recapitulates neocortical development process with VZ,OSVZ formation and the lamination organization of cortical layer structure.In addition,using patient-specific induced pluripotent stem cells (iPSCs) with dysfunction of the Aspm gene from a primary microcephaly patient,we demonstrate neurogenesis defects result in defective neuronal activity in patient organoids,suggesting a new strategy to study human developmental diseases in central nerve system.

  9. Neocortical connectivity during episodic memory formation.

    Science.gov (United States)

    Summerfield, Christopher; Greene, Matthew; Wager, Tor; Egner, Tobias; Hirsch, Joy; Mangels, Jennifer

    2006-05-01

    During the formation of new episodic memories, a rich array of perceptual information is bound together for long-term storage. However, the brain mechanisms by which sensory representations (such as colors, objects, or individuals) are selected for episodic encoding are currently unknown. We describe a functional magnetic resonance imaging experiment in which participants encoded the association between two classes of visual stimuli that elicit selective responses in the extrastriate visual cortex (faces and houses). Using connectivity analyses, we show that correlation in the hemodynamic signal between face- and place-sensitive voxels and the left dorsolateral prefrontal cortex is a reliable predictor of successful face-house binding. These data support the view that during episodic encoding, "top-down" control signals originating in the prefrontal cortex help determine which perceptual information is fated to be bound into the new episodic memory trace.

  10. Neocortical connectivity during episodic memory formation.

    Directory of Open Access Journals (Sweden)

    Christopher Summerfield

    2006-05-01

    Full Text Available During the formation of new episodic memories, a rich array of perceptual information is bound together for long-term storage. However, the brain mechanisms by which sensory representations (such as colors, objects, or individuals are selected for episodic encoding are currently unknown. We describe a functional magnetic resonance imaging experiment in which participants encoded the association between two classes of visual stimuli that elicit selective responses in the extrastriate visual cortex (faces and houses. Using connectivity analyses, we show that correlation in the hemodynamic signal between face- and place-sensitive voxels and the left dorsolateral prefrontal cortex is a reliable predictor of successful face-house binding. These data support the view that during episodic encoding, "top-down" control signals originating in the prefrontal cortex help determine which perceptual information is fated to be bound into the new episodic memory trace.

  11. NEOCORTICAL HYPERTROPHY FOLLOWING DEVELOPMENTAL HYPOTHYROIDISM IN RATS

    Science.gov (United States)

    Thyroid hormones (TH) are essential to the normal development of the brain. Although severe congenital hypothyroidism has long been associated with mental retardation and motor defects, it has only recently been established that even subtle decreases in maternal TH alter fetal br...

  12. Replicability and generalizability of PTSD networks

    DEFF Research Database (Denmark)

    Eiko I., Fried; Eidhof, Marloes B.; Palic, Sabina

    2018-01-01

    The growing literature conceptualizing mental disorders like Posttraumatic Stress Disorder (PTSD) as networks of interacting symptoms faces three key challenges. Prior studies predominantly used (a) small samples with low power for precise estimation, (b) non-clinical samples, and (c) single...... samples. This renders network structures in clinical data, and the extent to which networks replicate across datasets, unknown. To overcome these limitations, the present cross-cultural multisite study estimated regularized partial correlation networks of 16 PTSD symptoms across four datasets...... of traumatized patients receiving treatment for PTSD (total N=2,782). Despite differences in culture, trauma-type and severity of the samples, considerable similarities emerged, with moderate to high correlations between symptom profiles (0.43-0.82), network structures (0.62-0.74), and centrality estimates (0...

  13. Evolutionary approaches to cultural and linguistic diversity.

    Science.gov (United States)

    Steele, James; Jordan, Peter; Cochrane, Ethan

    2010-12-12

    Evolutionary approaches to cultural change are increasingly influential, and many scientists believe that a 'grand synthesis' is now in sight. The papers in this Theme Issue, which derives from a symposium held by the AHRC Centre for the Evolution of Cultural Diversity (University College London) in December 2008, focus on how the phylogenetic tree-building and network-based techniques used to estimate descent relationships in biology can be adapted to reconstruct cultural histories, where some degree of inter-societal diffusion will almost inevitably be superimposed on any deeper signal of a historical branching process. The disciplines represented include the three most purely 'cultural' fields from the four-field model of anthropology (cultural anthropology, archaeology and linguistic anthropology). In this short introduction, some context is provided from the history of anthropology, and key issues raised by the papers are highlighted.

  14. What Online Networks Offer: "Online Network Compositions and Online Learning Experiences of Three Ethnic Groups"

    Science.gov (United States)

    Lecluijze, Suzanne Elisabeth; de Haan, Mariëtte; Ünlüsoy, Asli

    2015-01-01

    This exploratory study examines ethno-cultural diversity in youth's narratives regarding their "online" learning experiences while also investigating how these narratives can be understood from the analysis of their online network structure and composition. Based on ego-network data of 79 respondents this study compared the…

  15. Social networks

    CERN Document Server

    Etaner-Uyar, A Sima

    2014-01-01

    The present volume provides a comprehensive resource for practitioners and researchers alike-both those new to the field as well as those who already have some experience. The work covers Social Network Analysis theory and methods with a focus on current applications and case studies applied in various domains such as mobile networks, security, machine learning and health. With the increasing popularity of Web 2.0, social media has become a widely used communication platform. Parallel to this development, Social Network Analysis gained in importance as a research field, while opening up many

  16. Network Warrior

    CERN Document Server

    Donahue, Gary

    2011-01-01

    Pick up where certification exams leave off. With this practical, in-depth guide to the entire network infrastructure, you'll learn how to deal with real Cisco networks, rather than the hypothetical situations presented on exams like the CCNA. Network Warrior takes you step by step through the world of routers, switches, firewalls, and other technologies based on the author's extensive field experience. You'll find new content for MPLS, IPv6, VoIP, and wireless in this completely revised second edition, along with examples of Cisco Nexus 5000 and 7000 switches throughout. Topics include: An

  17. Teaching Culture Through Films

    Institute of Scientific and Technical Information of China (English)

    徐婷

    2016-01-01

    Cultural teaching is an issue which is associated with complexity and paradox and also it is a big challenge for faculty. Teaching culture through films has become an important way of cross-cultural teaching This paper focuses on the reasons for teaching culture through films, the value and how it works. And finally it leads out the prospects of cultural teaching through films.

  18. Exploring Culture : Exercises, Stories and Synthetic Cultures

    NARCIS (Netherlands)

    Hofstede, G.J.

    2002-01-01

    A unique training book containing over 100 culture awareness exercises, dialogues, stories incidents and simulations that bring to life Geert Hofstede's five dimensions of culture. These dimensions are: power distance, collectivism versus individualism, femininity versus masculinity, uncertainly

  19. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC......)’ have not been considered much in the literature. In this article we present Heterodox networks as an innovative and alternate approach to handle the PTC congestion. We describe two different approaches to combat the PTC congestion where the traditional terrestrial infrastructure fails to provide......-Configurable Intelligent Distributed Antenna System (SCIDAS)’ that overlays intelligence over the conventional DAS architecture and latter is in the form of a swarm of intelligent hovering base stations working in a team to cooperatively resolve the PTC congestion at the Area of Event (AoE). A suitable network...

  20. Networking Japan

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    Human Resource Development was the first and remains an important pillar in Japanese foreign aid. I will argue that Japan has access to a global network of alumni who will co-define Japanese foreign aid in the future, because Japan has encouraged alumni societies and networking since 1965. A total...... of more than a million people in more than 100 countries have attended courses in Japan funded fully or partly by Japanese ODA since the inception of the technical assistance programs in 1954 through the Colombo Plan and since 1959 through the Association of Overseas Technical Scholarships (AOTS from 2009...... HIDA). Many of these alumni have and will in the future exchange ideas and keep contact not only to Japan, but also to fellow alumni around the globe and, thereby, practice south-south exchanges, which are made possible and traceable by their established alumni network and the World Network of Friends...

  1. Sentinel Network

    Science.gov (United States)

    The Sentinel Network is an integrated, electronic, national medical product safety initiative that compiles information about the safe and effective use of medical products accessible to patients and healthcare practitioners.

  2. Exchange Network

    Science.gov (United States)

    The Environmental Information Exchange Network (EN) is an Internet-based system used by state, tribal and territorial partners to securely share environmental and health information with one another and EPA.

  3. Diversity Networks

    Science.gov (United States)

    and professional growth of women through networking, mentoring and training. We strive to ensure that will be used. National Processing Center Seniors Leader: Jo Anne Hankins Champion: Eric Milliner NO

  4. Nepal Networking

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    , as a Danida fellow. Today, the older sister works in Nepal and the younger in Seattle, where they still make use of their personal networks including connections to their fellow alumni of technical assistance courses. Inspired by work on social remittances in combination with network theory , I argue......Technical Assistance courses have many functions apart from disseminating knowledge and information, one such function is to engender networks. During the course period, participants meet and establish contact and some of these contacts remain connections between alumni for many years after...... the courses are finished. The alumni networks depend on the uses they are put to by the individual alumni and the support they get from alumni and host countries. The United Nations initiated technical assistance courses in the late 1940s in order to train nationals from developing countries as a means...

  5. computer networks

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2002-01-01

    Full Text Available In this paper, we construct a new dynamic model for the Token Bucket (TB algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.

  6. Dehistoricized Cultural Identity and Cultural Othering

    Science.gov (United States)

    Weiguo, Qu

    2013-01-01

    The assumption that each culture has its own distinctive identity has been generally accepted in the discussion of cultural identities. Quite often identity formation is not perceived as a dynamic and interactive ongoing process that engages other cultures and involves change in its responses to different challenges at different times. I will…

  7. Cultural Understanding Through Cross-Cultural Analysis.

    Science.gov (United States)

    Briere, Jean-Francois

    1986-01-01

    A college course used an explicit intercultural approach and collective research activities to compare French and American cultures and to examine the reasons for cultural attitudes and culture conflict. Class assignments dealt with contrastive analyses of American and French institutions like advertising, cinema, feminism, etc. (MSE)

  8. Neural networks

    International Nuclear Information System (INIS)

    Denby, Bruce; Lindsey, Clark; Lyons, Louis

    1992-01-01

    The 1980s saw a tremendous renewal of interest in 'neural' information processing systems, or 'artificial neural networks', among computer scientists and computational biologists studying cognition. Since then, the growth of interest in neural networks in high energy physics, fueled by the need for new information processing technologies for the next generation of high energy proton colliders, can only be described as explosive

  9. Organizational Networks

    DEFF Research Database (Denmark)

    Grande, Bård; Sørensen, Ole Henning

    1998-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept of organizational network are identified and critically discussed. Special focus is placed on how information and communication technologies as communication mediators and cognitive pictures influence...... the organizational forms discussed in the paper. It is asserted that the underlying organizational phenomena are not changing but that the manifestations and representations are shifting due to technological developments....

  10. Microalgal Culture Collection Transfers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Milford Microalgal culture Collection holds over 200 live cultures representing 13 classes of of algae. The cultures are maintained in three different growing...

  11. Routine sputum culture

    Science.gov (United States)

    Sputum culture ... There, it is placed in a special dish (culture). It is then watched to see if bacteria ... Elsevier; 2018:chap 36. Chernecky CC, Berger BJ. Culture, routine. In: Chernecky CC, Berger BJ, eds. Laboratory ...

  12. Lymph node culture

    Science.gov (United States)

    Culture - lymph node ... or viruses grow. This process is called a culture. Sometimes, special stains are also used to identify specific cells or microorganisms before culture results are available. If needle aspiration does not ...

  13. Cross-cultural awareness

    OpenAIRE

    БУРЯК Н.Ю.

    2016-01-01

    The article deals with the importance of cultural awareness for businesspeople when they go abroad. It also gives some cultural advice and factors which are thought to be the most important in creating a culture.

  14. Teaching Culturally Diverse Students.

    Science.gov (United States)

    Correa, Vivian; Tulbert, Beth

    1991-01-01

    Characteristics of culturally diverse students are discussed in terms of language, culture, and socioeconomic factors. Meeting the educational needs of culturally diverse students can involve interactive teaming of professionals; parent involvement; and providing appropriate services, assessment, curriculum, and instruction. (JDD)

  15. Cerebrospinal fluid culture

    Science.gov (United States)

    ... Alternative Names Culture - CSF; Spinal fluid culture; CSF culture Images Pneumococci organism References Karcher DS, McPherson RA. Cerebrospinal, synovial, serous body fluids, and alternative specimens. In: McPherson RA, Pincus ...

  16. Organizations, projects and culture

    NARCIS (Netherlands)

    J. van Cleeff; Pieter van Nispen tot Pannerden

    2016-01-01

    Purpose: to explore and demonstrate the effects of organizational culture on projects, in particular project culture and project management style. Methodology/approach: descriptive and explorative; through students’ groups. Findings: the cultural relationship between organizations, their projects

  17. Cultura tecnológica e redes sociotécnicas: um estudo sobre o portal da rede municipal de ensino de São Paulo Technological culture and sociotechnical networks: a study of the São Paulo municipal school system web portal

    Directory of Open Access Journals (Sweden)

    Zulmira Medeiros

    2008-04-01

    change, situating in this context the educator and his/her appropriation of the technological culture. It then deals with the constitution of sociotechnical networks in the educational environment, having the Internet as a facilitator. In so doing, the text also touches on the issues of social networks and educational web portals. The fieldwork investigated the process of constitution of a sociotechnical network in a municipal school system. Observations, assessments, questionnaires, and interviews built a case study, in which it was possible to follow the creation, implementation, and use of an Internet portal as a new space for the communication, interaction, and exchange of information among the school community. The investigation centered on the figure of the educator and of his/her perception of this space. Based on the assumption that our relationship to technology entails a process of appropriation of the technological culture, which directly influences our actions in this networked society, we conclude that educational web portals can be used by schools in a productive way, in collaboration among the various agents of the educational community, once this process takes into account, amongst other factors, the technological culture of that particular community.

  18. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  19. Towards an International Culture: Gen Y Students and SNS?

    Science.gov (United States)

    Lichy, Jessica

    2012-01-01

    This article reports the findings of a small-scale investigation into the Internet user behaviour of generation Y (Gen Y) students, with particular reference to social networking sites. The study adds to the literature on cross-cultural Internet user behaviour with specific reference to Gen Y and social networking. It compares how a cohort of…

  20. Functional optical probing of the hippocampal trisynaptic circuit in vitro: network dynamics, filter properties, and polysynaptic induction of CA1 LTP.

    Science.gov (United States)

    Stepan, Jens; Dine, Julien; Eder, Matthias

    2015-01-01

    Decades of brain research have identified various parallel loops linking the hippocampus with neocortical areas, enabling the acquisition of spatial and episodic memories. Especially the hippocampal trisynaptic circuit [entorhinal cortex layer II → dentate gyrus (DG) → cornu ammonis (CA)-3 → CA1] was studied in great detail because of its seemingly simple connectivity and characteristic structures that are experimentally well accessible. While numerous researchers focused on functional aspects, obtained from a limited number of cells in distinct hippocampal subregions, little is known about the neuronal network dynamics which drive information across multiple synapses for subsequent long-term storage. Fast voltage-sensitive dye imaging in vitro allows real-time recording of activity patterns in large/meso-scale neuronal networks with high spatial resolution. In this way, we recently found that entorhinal theta-frequency input to the DG most effectively passes filter mechanisms of the trisynaptic circuit network, generating activity waves which propagate across the entire DG-CA axis. These "trisynaptic circuit waves" involve high-frequency firing of CA3 pyramidal neurons, leading to a rapid induction of classical NMDA receptor-dependent long-term potentiation (LTP) at CA3-CA1 synapses (CA1 LTP). CA1 LTP has been substantially evidenced to be essential for some forms of explicit learning in mammals. Here, we review data with particular reference to whole network-level approaches, illustrating how activity propagation can take place within the trisynaptic circuit to drive formation of CA1 LTP.