Onset and maximum values of electromyographic amplitude during prone hip extension after neurodynamic technique in patients with lumbosciatic pain: A pilot study.

PubMed

Horment-Lara, Giselle; Cruz-Montecinos, Carlos; Núñez-Cortés, Rodrigo; Letelier-Horta, Pablo; Henriquez-Fuentes, Luis

2016-04-01

The mechanisms underlying the effects of neurodynamic techniques are still unknown. Therefore, the aim of this study was to provide a starting point for future research on explaining why neurodynamic techniques affect muscular activities in patients with sciatic pain. A double-blind trial was conducted in 12 patients with lumbosciatica. Surface electromyography activity was assessed for different muscles during prone hip extension. Pre- and post-intervention values for muscle activity onset and maximal amplitude signals were determined. There was a significant reduction in the surface electromyography activity of maximal amplitude in the erector spinae and contralateral erector spinae (p < 0.05). Additionally, gluteus maximus (p < 0.05) activity onset was delayed post-intervention. Self-neurodynamic sliding techniques modify muscular activity and onset during prone hip extension, possibly reducing unnecessary adaptations for protecting injured components. Future work will analyze the effects of self-neurodynamic sliding techniques during other physical tasks. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sciatic nerve stiffness is not changed immediately after a slump neurodynamics technique.

PubMed

Neto, Tiago; Freitas, Sandro R; Andrade, Ricardo J; Gomes, João; Vaz, João; Mendes, Bruno; Firmino, Telmo; Nordez, Antoine; Oliveira, Raúl

2017-01-01

Neurodynamics techniques aim to assess and improve neural mechanosensitivity. However, there is no in vivo evidence regarding the mechanical effects of these techniques in the nerve stiffness. This study examined the immediate effects of a slump neurodynamics technique in the sciatic nerve shear wave velocity (SWV. i.e. an index of stiffness) using ultrasound-based elastography. Fourteen healthy participants were included in this experiment. Sciatic SWV and ankle passive torque were measured during a passive ankle dorsiflexion motion (2°/s), before and immediately after 3 minutes of slump neurodynamics technique, randomly applied to one lower limb. The contralateral limb served as control. The slump intervention did not change the sciatic SWV (P=0.78), nor the dorsiflexion passive torque (P=0.14), throughout the ankle dorsiflexion motion. Excellent values of intra-rater repeatability (ICC=0.88, 0.68-0.96), and low values of standard error of measurement (0.59 m/s, 0.35-1.15m/s), were observed for the SWV measurements. The sciatic nerve stiffness of healthy participants did not change immediately after a slump neurodynamics technique, suggesting a compliance of the neural tissue to tensile loads. However, these results ought to be confirmed using other neurodynamics techniques and in other populations (e.g. peripheral neuropathies). III.

Computational Intelligence Applications for Defense

DTIC Science & Technology

2011-02-18

Eds. Neurodynamics of Higher-Level Cognition and Consciousness. Heidelberg, Germany: Springer-Verlag, 2007. [29] L. I. Perlovsky, R. Kozma...Editorial - Neurodynamics of Cognition and Consciousness,” In Neurodynamics of Cognition and Consciousness, Perlovsky, L., R. Kozma, Eds., Springer...difficulties: complexity and logic……………………………………………………...3 3. Cognitive mechanisms: mathematical models and experimental evidence………………...4 4

Sciatic nerve stiffness is not changed immediately after a slump neurodynamics technique

PubMed Central

Neto, Tiago; Freitas, Sandro R; Andrade, Ricardo J; Gomes, João; Vaz, João; Mendes, Bruno; Firmino, Telmo; Nordez, Antoine; Oliveira, Raúl

2017-01-01

Summary Background Neurodynamics techniques aim to assess and improve neural mechanosensitivity. However, there is no in vivo evidence regarding the mechanical effects of these techniques in the nerve stiffness. This study examined the immediate effects of a slump neurodynamics technique in the sciatic nerve shear wave velocity (SWV. i.e. an index of stiffness) using ultrasound-based elastography. Methods Fourteen healthy participants were included in this experiment. Sciatic SWV and ankle passive torque were measured during a passive ankle dorsiflexion motion (2°/s), before and immediately after 3 minutes of slump neurodynamics technique, randomly applied to one lower limb. The contralateral limb served as control. Results The slump intervention did not change the sciatic SWV (P=0.78), nor the dorsiflexion passive torque (P=0.14), throughout the ankle dorsiflexion motion. Excellent values of intra-rater repeatability (ICC=0.88, 0.68–0.96), and low values of standard error of measurement (0.59 m/s, 0.35–1.15m/s), were observed for the SWV measurements. Conclusions The sciatic nerve stiffness of healthy participants did not change immediately after a slump neurodynamics technique, suggesting a compliance of the neural tissue to tensile loads. However, these results ought to be confirmed using other neurodynamics techniques and in other populations (e.g. peripheral neuropathies). Level of evidence III. PMID:29387655

Methodology Investigation of AI(Artificial Intelligence) Test Officer Support Tool. Volume 2

DTIC Science & Technology

1989-03-01

a mathematical representation of a PE and its connections. This representation describes the " neurodynamics " of a PE. A sigmoid transfer function is...Element(i) Neurodynamics : Summation Function: Wo*XO + W,*X + W*X "X 0 0 1 1 2 W~fn Transfer Function: F(k) = (1 + e k) Output: x. - F(I) Figure 2-4...simplifies the description of the network operations. Thus, one or more PEs grouped together, with the same neurodynamics , is a layer [reference 5]. A

Implantable Microsystems for Anatomical Rewiring of Cortical Circuitry: A New Approach for Brain Repair

DTIC Science & Technology

2009-03-01

dopamine or serotonin, provide outputs to large regions of the brain that affect mood, learning, and cognition [4]. Hence, understanding brain function on a...Sutton, B. T. Higashikubo, C. A. Chestek, H. J. Chiel, and H. B. Martin, “Diamond electrodes for neurodynamic studies in Aplysia californica,” Diam

[Neurodynamic Bases of Imitation Learning and Episodic Memory].

PubMed

Tsukerman, V D

2016-01-01

In this review, three essentially important processes in development of cognitive behavior are considered: knowledge of a spatial environment by means of physical activity, coding and a call of an existential context of episodic memory and imitation learning based on the mirror neural mechanism. The data show that the parietal and frontal system of learning by imitation, allows the developing organism to seize skills of management and motive synergies in perisomatic space, to understand intentions and the purposes of observed actions of other individuals. At the same time a widely distributed parietal and frontal and entorhinal-hippocampal system mediates spatial knowledge and the solution of the navigation tasks important for creation of an existential context of episodic memory.

Normal neurodynamic responses of the femoral slump test.

PubMed

Lai, Weng-Hang; Shih, Yi-Fen; Lin, Pei-Ling; Chen, Wen-Yin; Ma, Hsiao-Li

2012-04-01

Femoral slump test is a neurodynamic testing, which could be used to assess the mechanosensitivity of the femoral component of the nervous system. Although Trainor and Pinnington reported the diagnosis accuracy of the femoral slump test, the neurodynamic responses of the femoral slump test have never been studied. The purposes of this study were to evaluate whether maneuvers that changed the nerve tension altered the responses of the femoral slump test and if these responses were influenced by gender and leg dominance; and to identify the correlations between flexibility and measured hip extension angle. Thirty-two asymptomatic subjects (16 males, 16 females) were recruited. The femoral slump test was performed in trunk slump and neutral positions, and cervical extension was used as the structure differential technique. Hip extension angle and visual analog scale (VAS) of thigh pain was measured during the test. Our results showed the decrease of nerve tension significantly increased hip extension ROM (P < 0.001) and lowered pain intensity (P < 0.001). The hip extension ROM was similar between genders but smaller for the dominant leg, as compared to the non-dominant side (P < 0.05); and the hip ROM did not correlate with any of the flexibility indices (P > 0.05). These findings indicated that femoral slump test resulted in normal neurodynamic responses in individuals free of lower extremity problems, and these responses were independent of the influence of muscle flexibility or gender. Future research should emphasize the use of femoral slump test in patient groups such as low back and anterior knee pain. Copyright © 2011 Elsevier Ltd. All rights reserved.

ViSA: A Neurodynamic Model for Visuo-Spatial Working Memory, Attentional Blink, and Conscious Access

ERIC Educational Resources Information Center

Simione, Luca; Raffone, Antonino; Wolters, Gezinus; Salmas, Paola; Nakatani, Chie; Belardinelli, Marta Olivetti; van Leeuwen, Cees

2012-01-01

Two separate lines of study have clarified the role of selectivity in conscious access to visual information. Both involve presenting multiple targets and distracters: one "simultaneously" in a spatially distributed fashion, the other "sequentially" at a single location. To understand their findings in a unified framework, we propose a…

Machine Understanding of Human Implicit Intention

DTIC Science & Technology

2013-05-18

Cognitive Neurodynamics , Hokkaido, Japan, June 2011, Hokkaido, Japan (Plenary Talk) - Soo-Young Lee, Implicit Intention Recognition and Hierarchical...subject’s response with the accuracy of about 80% by SVM. 15. SUBJECT TERMS Brain Science and Engineering; Cognitive Neuroscience; Human-Computer...oscillations have been related to a variety of functions such as perception, cognition , sleep, etc. For a long time, researchers have found the sensory and

Towards oscillations-based simulation of social systems: a neurodynamic approach

NASA Astrophysics Data System (ADS)

Plikynas, Darius; Basinskas, Gytis; Laukaitis, Algirdas

2015-04-01

This multidisciplinary work presents synopsis of theories in the search for common field-like fundamental principles of self-organisation and communication existing on quantum, cellular, and even social levels. Based on these fundamental principles, we formulate conceptually novel social neuroscience paradigm (OSIMAS), which envisages social systems emerging from the coherent neurodynamical processes taking place in the individual mind-fields. In this way, societies are understood as global processes emerging from the superposition of the conscious and subconscious mind-fields of individual members of society. For the experimental validation of the biologically inspired OSIMAS paradigm, we have designed a framework of EEG-based experiments. Initial baseline individual tests of spectral cross-correlations of EEG-recorded brainwave patterns for some mental states have been provided in this paper. Preliminary experimental results do not refute the main OSIMAS postulates. This paper also provides some insights for the construction of OSIMAS-based simulation models.

Statistical Neurodynamics.

NASA Astrophysics Data System (ADS)

Paine, Gregory Harold

1982-03-01

The primary objective of the thesis is to explore the dynamical properties of small nerve networks by means of the methods of statistical mechanics. To this end, a general formalism is developed and applied to elementary groupings of model neurons which are driven by either constant (steady state) or nonconstant (nonsteady state) forces. Neuronal models described by a system of coupled, nonlinear, first-order, ordinary differential equations are considered. A linearized form of the neuronal equations is studied in detail. A Lagrange function corresponding to the linear neural network is constructed which, through a Legendre transformation, provides a constant of motion. By invoking the Maximum-Entropy Principle with the single integral of motion as a constraint, a probability distribution function for the network in a steady state can be obtained. The formalism is implemented for some simple networks driven by a constant force; accordingly, the analysis focuses on a study of fluctuations about the steady state. In particular, a network composed of N noninteracting neurons, termed Free Thinkers, is considered in detail, with a view to interpretation and numerical estimation of the Lagrange multiplier corresponding to the constant of motion. As an archetypical example of a net of interacting neurons, the classical neural oscillator, consisting of two mutually inhibitory neurons, is investigated. It is further shown that in the case of a network driven by a nonconstant force, the Maximum-Entropy Principle can be applied to determine a probability distribution functional describing the network in a nonsteady state. The above examples are reconsidered with nonconstant driving forces which produce small deviations from the steady state. Numerical studies are performed on simplified models of two physical systems: the starfish central nervous system and the mammalian olfactory bulb. Discussions are given as to how statistical neurodynamics can be used to gain a better understanding of the behavior of these systems.

Output Feedback-Based Boundary Control of Uncertain Coupled Semilinear Parabolic PDE Using Neurodynamic Programming.

PubMed

Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

2018-04-01

In this paper, neurodynamic programming-based output feedback boundary control of distributed parameter systems governed by uncertain coupled semilinear parabolic partial differential equations (PDEs) under Neumann or Dirichlet boundary control conditions is introduced. First, Hamilton-Jacobi-Bellman (HJB) equation is formulated in the original PDE domain and the optimal control policy is derived using the value functional as the solution of the HJB equation. Subsequently, a novel observer is developed to estimate the system states given the uncertain nonlinearity in PDE dynamics and measured outputs. Consequently, the suboptimal boundary control policy is obtained by forward-in-time estimation of the value functional using a neural network (NN)-based online approximator and estimated state vector obtained from the NN observer. Novel adaptive tuning laws in continuous time are proposed for learning the value functional online to satisfy the HJB equation along system trajectories while ensuring the closed-loop stability. Local uniformly ultimate boundedness of the closed-loop system is verified by using Lyapunov theory. The performance of the proposed controller is verified via simulation on an unstable coupled diffusion reaction process.

Efforts and Programs of the Department of Defense Relating to the Prevention, Mitigation, and Treatment of Blast Injuries

DTIC Science & Technology

2008-01-01

potential data from health control subjects. Investigators have published three papers on this research; one in Cognitive Neurodynamics and two...included in the Proceedings of the First International Conference on Cognitive Neurodynamics . Prototype Bandage Under Development to Control Hemorrhage...exposures such as blast events. This includes determination of scientifically based tests and standards for cognitive , emotional, and physical duty

On consciousness, resting state fMRI, and neurodynamics

PubMed Central

2010-01-01

Background During the last years, functional magnetic resonance imaging (fMRI) of the brain has been introduced as a new tool to measure consciousness, both in a clinical setting and in a basic neurocognitive research. Moreover, advanced mathematical methods and theories have arrived the field of fMRI (e.g. computational neuroimaging), and functional and structural brain connectivity can now be assessed non-invasively. Results The present work deals with a pluralistic approach to "consciousness'', where we connect theory and tools from three quite different disciplines: (1) philosophy of mind (emergentism and global workspace theory), (2) functional neuroimaging acquisitions, and (3) theory of deterministic and statistical neurodynamics – in particular the Wilson-Cowan model and stochastic resonance. Conclusions Based on recent experimental and theoretical work, we believe that the study of large-scale neuronal processes (activity fluctuations, state transitions) that goes on in the living human brain while examined with functional MRI during "resting state", can deepen our understanding of graded consciousness in a clinical setting, and clarify the concept of "consiousness" in neurocognitive and neurophilosophy research. PMID:20522270

Regulating Cortical Neurodynamics for Past, Present and Future

NASA Astrophysics Data System (ADS)

Liljenström, Hans

2002-09-01

Behaving systems, biological as well as artificial, need to respond quickly and accurately to changes in the environment. The response is dependent on stored memories, and novel situations should be learnt for the guidance of future behavior. A highly nonlinear system dynamics is required in order to cope with a complex and changing environment, and this dynamics should be regulated to match the demands of the current situation, and to predict future behavior. In many cases the dynamics should be regulated to minimize processing time. We use computer simulations of cortical structures in order to investigate how the neurodynamics of these systems can be regulated for optimal performance in an unknown and changing environment. In particular, we study how cortical oscillations can serve to amplify weak signals and sustain an input pattern for more accurate information processing, and how chaotic-like behavior could increase the sensitivity in initial, exploratory states. We mimic regulating mechanisms based on neuromodulators, intrinsic noise levels, and various synchronizing effects. We find optimal noise levels where system performance is maximized, and neuromodulatory strategies for an efficient pattern recognition, where the anticipatory state of the system plays an important role.

Optical Processing.

DTIC Science & Technology

1985-12-31

34 Optics Letters, 2 (1), 1-3 (1978). 7. Grossberg, S., "Adaptive Resonance in Development, Perception and Cognition ," SIAM-AMS Proc., 13, 107-156...Illusions," Biol. Cybernetics, 23, 187-202, (1976b). 11. Grossberg, S., "How Does A Brain Build a Cognitive Code?", Psychol. Review, 87 (1), 1-51 (1980...34perceptron" (F. Rosenblatt, Principles of Neurodynamics ), workers in the neural network field have been seeking to understand how neural networks can perform

Near Optimal Event-Triggered Control of Nonlinear Discrete-Time Systems Using Neurodynamic Programming.

PubMed

Sahoo, Avimanyu; Xu, Hao; Jagannathan, Sarangapani

2016-09-01

This paper presents an event-triggered near optimal control of uncertain nonlinear discrete-time systems. Event-driven neurodynamic programming (NDP) is utilized to design the control policy. A neural network (NN)-based identifier, with event-based state and input vectors, is utilized to learn the system dynamics. An actor-critic framework is used to learn the cost function and the optimal control input. The NN weights of the identifier, the critic, and the actor NNs are tuned aperiodically once every triggered instant. An adaptive event-trigger condition to decide the trigger instants is derived. Thus, a suitable number of events are generated to ensure a desired accuracy of approximation. A near optimal performance is achieved without using value and/or policy iterations. A detailed analysis of nontrivial inter-event times with an explicit formula to show the reduction in computation is also derived. The Lyapunov technique is used in conjunction with the event-trigger condition to guarantee the ultimate boundedness of the closed-loop system. The simulation results are included to verify the performance of the controller. The net result is the development of event-driven NDP.

Learning Complex Cell Invariance from Natural Videos: A Plausibility Proof

DTIC Science & Technology

2007-12-26

is in the McGovern Institute for Brain Research at MIT, as well as in the Dept. of Brain & Cognitive Sciences, and which is affiliated with the...stimulation induce plasticity? Proc. Nat. Acad. Sci. USA, 92:9682–9686. Deco, G. and Rolls, E. T. (2004). A neurodynamical cor- tical model of visual attention...and invariant object recognition. Vision Res, 44(6):621–42. Deco, G. and Rolls, E. T. (2005). Neurodynamics of biased competition and cooperation for

Neural nets with terminal chaos for simulation of non-deterministic patterns

NASA Technical Reports Server (NTRS)

Zak, Michail

1993-01-01

Models for simulating some aspects of neural intelligence are presented and discussed. Special attention is given to terminal neurodynamics as a particular architecture of terminal dynamics suitable for modeling information flows. Applications of terminal chaos to information fusion as well as to planning and modeling coordination among neurons in biological systems are disussed.

Dynamical aspects of behavior generation under constraints

PubMed Central

Harter, Derek; Achunala, Srinivas

2007-01-01

Dynamic adaptation is a key feature of brains helping to maintain the quality of their performance in the face of increasingly difficult constraints. How to achieve high-quality performance under demanding real-time conditions is an important question in the study of cognitive behaviors. Animals and humans are embedded in and constrained by their environments. Our goal is to improve the understanding of the dynamics of the interacting brain–environment system by studying human behaviors when completing constrained tasks and by modeling the observed behavior. In this article we present results of experiments with humans performing tasks on the computer under variable time and resource constraints. We compare various models of behavior generation in order to describe the observed human performance. Finally we speculate on mechanisms how chaotic neurodynamics can contribute to the generation of flexible human behaviors under constraints. PMID:19003514

Interdisciplinary Study on Artificial Intelligence.

DTIC Science & Technology

1983-07-01

systems, uiophysics of information processing, cognitive science, and traditional artificial intelligence. The objective behi d this objective was to...information processing, cognitive science, and traditional * artificial intelligence. The objective behind this objective was to provide a vehicle for reviewing...Another departure from ’classical’ neurodynamics must be sought in the strong coupling between the micro and macroscopic scales. No other physical mechanism

Neurodynamical model of collective brain

NASA Technical Reports Server (NTRS)

Zak, Michail

1992-01-01

A dynamical system which mimics collective purposeful activities of a set of units of intelligence is introduced and discussed. A global control of the unit activities is replaced by the probabilistic correlations between them. These correlations are learned during a long term period of performing collective tasks, and are stored in the synaptic interconnections. The model is represented by a system of ordinary differential equations with terminal attractors and repellers, and does not contain any man-made digital devices.

Self-Organized Criticality, Plasticity and Sensorimotor Coupling. Explorations with a Neurorobotic Model in a Behavioural Preference Task

PubMed Central

Aguilera, Miguel; Barandiaran, Xabier E.; Bedia, Manuel G.; Seron, Francisco

2015-01-01

During the last two decades, analysis of 1/ƒ noise in cognitive science has led to a considerable progress in the way we understand the organization of our mental life. However, there is still a lack of specific models providing explanations of how 1/ƒ noise is generated in coupled brain-body-environment systems, since existing models and experiments typically target either externally observable behaviour or isolated neuronal systems but do not address the interplay between neuronal mechanisms and sensorimotor dynamics. We present a conceptual model of a minimal neurorobotic agent solving a behavioural task that makes it possible to relate mechanistic (neurodynamic) and behavioural levels of description. The model consists of a simulated robot controlled by a network of Kuramoto oscillators with homeostatic plasticity and the ability to develop behavioural preferences mediated by sensorimotor patterns. With only three oscillators, this simple model displays self-organized criticality in the form of robust 1/ƒ noise and a wide multifractal spectrum. We show that the emergence of self-organized criticality and 1/ƒ noise in our model is the result of three simultaneous conditions: a) non-linear interaction dynamics capable of generating stable collective patterns, b) internal plastic mechanisms modulating the sensorimotor flows, and c) strong sensorimotor coupling with the environment that induces transient metastable neurodynamic regimes. We carry out a number of experiments to show that both synaptic plasticity and strong sensorimotor coupling play a necessary role, as constituents of self-organized criticality, in the generation of 1/ƒ noise. The experiments also shown to be useful to test the robustness of 1/ƒ scaling comparing the results of different techniques. We finally discuss the role of conceptual models as mediators between nomothetic and mechanistic models and how they can inform future experimental research where self-organized critically includes sensorimotor coupling among the essential interaction-dominant process giving rise to 1/ƒ noise. PMID:25706744

Top-down and bottom-up neurodynamic evidence in patients with tinnitus.

PubMed

Hong, Sung Kwang; Park, Sejik; Ahn, Min-Hee; Min, Byoung-Kyong

2016-12-01

Although a peripheral auditory (bottom-up) deficit is an essential prerequisite for the generation of tinnitus, central cognitive (top-down) impairment has also been shown to be an inherent neuropathological mechanism. Using an auditory oddball paradigm (for top-down analyses) and a passive listening paradigm (for bottom-up analyses) while recording electroencephalograms (EEGs), we investigated whether top-down or bottom-up components were more critical in the neuropathology of tinnitus, independent of peripheral hearing loss. We observed significantly reduced P300 amplitudes (reflecting fundamental cognitive processes such as attention) and evoked theta power (reflecting top-down regulation in memory systems) for target stimuli at the tinnitus frequency of patients with tinnitus but without hearing loss. The contingent negative variation (reflecting top-down expectation of a subsequent event prior to stimulation) and N100 (reflecting auditory bottom-up selective attention) were different between the healthy and patient groups. Interestingly, when tinnitus patients were divided into two subgroups based on their P300 amplitudes, their P170 and N200 components, and annoyance and distress indices to their tinnitus sound were different. EEG theta-band power and its Granger causal neurodynamic results consistently support a double dissociation of these two groups in both top-down and bottom-up tasks. Directed cortical connectivity corroborates that the tinnitus network involves the anterior cingulate and the parahippocampal areas, where higher-order top-down control is generated. Together, our observations provide neurophysiological and neurodynamic evidence revealing a differential engagement of top-down impairment along with deficits in bottom-up processing in patients with tinnitus but without hearing loss. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Differential diagnosis and management of an older runner with an atypical neurodynamic presentation: a case for clinical reasoning.

PubMed

Sylvain, Jonathan; Reiman, Michael P

2015-04-01

Case Report. The purpose of this case report is to describe the clinical reasoning process involved with the differential diagnosis and management of a 69 year-old male runner reporting a six month history of insidious onset of left sided low back and buttock pain of low to medium degree of irritability. The case presented describes the utilization of clinical reasoning by a clinician in fellowship training when a patient with atypical adverse neurodynamic dysfunction related to running was encountered. The patient's physical examination was relatively unremarkable. Assessment of the patient's subjective history, self-report measures [Oswestry Disability Index (ODI), global rating of change scale (GROC)], objective findings, and tests and measures led to a working diagnosis of atypical adverse peripheral neurodynamic dysfunction. The lumbar spine, sacroiliac joint, hip joint and lower extremity were ruled out by a comprehensive subjective and objective examination. The diagnosis of adverse neurodynamic dysfunction became a diagnosis of exclusion. Returning two and a half weeks after initial evaluation the patient reported no pain with running. Twelve weeks after the initiation of physical therapy, the patient was contacted via email. He was sent, and asked to fill out an ODI. The patient demonstrated an improvement in ODI from 10% to 2%. He also reported that he continued to run after treatment without pain. Determining the source of a patient complaint can occasionally be an arduous undertaking. Pathological sources of a patient's symptoms may not be easily determined. Development of differential diagnosis and clinical reasoning skills is imperative. Improving clinical reasoning skills requires deliberate practice through reflective thinking before, during, and after patient interactions. Refinement of these skills leads to the primary goal of identifying the patient's clinical presentation, thus matching it with the most effective treatment approach. Level 4.

Biomorphic Networks for ATR and Higher-Level Processing.

DTIC Science & Technology

1998-01-10

Publications during this period: 1. N.H. Farhat, "Biomorphic Dynamical Networks for Cognition and Control", Journal of Intelligent and Rototic Systems...34 Neurodynamic networks for recognition of radar targets", Ph.D. dissertation, University of Pennsyl- vania, 1992. 2. J. Wood, "Invariant pattern...167-177,1998. 167 © 1998 Kluwer Academic Publishers. Printed in the Netherlands. Biomorphic Dynamical Networks for Cognition and Control N. H

Active Control of Complex Systems via Dynamic (Recurrent) Neural Networks

DTIC Science & Technology

1992-05-30

course, to on-going changes brought about by learning processes. As research in neurodynamics proceeded, the concept of reverberatory information flows...Microstructure of Cognition . Vol. 1: Foundations, M.I.T. Press, Cambridge, Massachusetts, pp. 354-361, 1986. 100 I Schwarz, G., "Estimating the dimension of a...Continually Running Fully Recurrent Neural Networks, ICS Report 8805, Institute of Cognitive Science, University of California at San Diego, 1988. 10 II

A MURI Center for Intelligent Biomimetic Image Processing and Classification

DTIC Science & Technology

2007-11-01

Grossberg, S., Editor of a new journal on Current Opinion in Cognitive Neurodynamics , 2005. 34. Grossberg, S., Editor of the new International...Department of Cognitive and Neural Systems 677 Beacon Street Boston MA 02215 steve(&bu.edu Phone: 617-353-7857 Fax: 617-353-7755 http://cns.bu.edu...memory, learning of sequential plans, and sequence performance during cognitive information processing; (8) coordinated ballistic and smooth pursuit

Memory Reconsolidation and Computational Learning

DTIC Science & Technology

2010-03-01

Cooper and H.T. Siegelmann, "Memory Reconsolidation for Natural Language Processing," Cognitive Neurodynamics , 3, 2009: 365-372. M.M. Olsen, N...computerized memories and other state of the art cognitive architectures, our memory system has the ability to process on-line and in real-time as...on both continuous and binary inputs, unlike state of the art methods in case based reasoning and in cognitive architectures, which are bound to

ViSA: a neurodynamic model for visuo-spatial working memory, attentional blink, and conscious access.

PubMed

Simione, Luca; Raffone, Antonino; Wolters, Gezinus; Salmas, Paola; Nakatani, Chie; Belardinelli, Marta Olivetti; van Leeuwen, Cees

2012-10-01

Two separate lines of study have clarified the role of selectivity in conscious access to visual information. Both involve presenting multiple targets and distracters: one simultaneously in a spatially distributed fashion, the other sequentially at a single location. To understand their findings in a unified framework, we propose a neurodynamic model for Visual Selection and Awareness (ViSA). ViSA supports the view that neural representations for conscious access and visuo-spatial working memory are globally distributed and are based on recurrent interactions between perceptual and access control processors. Its flexible global workspace mechanisms enable a unitary account of a broad range of effects: It accounts for the limited storage capacity of visuo-spatial working memory, attentional cueing, and efficient selection with multi-object displays, as well as for the attentional blink and associated sparing and masking effects. In particular, the speed of consolidation for storage in visuo-spatial working memory in ViSA is not fixed but depends adaptively on the input and recurrent signaling. Slowing down of consolidation due to weak bottom-up and recurrent input as a result of brief presentation and masking leads to the attentional blink. Thus, ViSA goes beyond earlier 2-stage and neuronal global workspace accounts of conscious processing limitations. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Extending Hypothesis Testing of Edge Organizations Using Functional Magnetic Resonance Imaging (fMRI) During ELICIT

DTIC Science & Technology

2010-06-01

task difficulty and response correctness on neural systems supporting fluid reasoning. Cognitive Neurodynamics 1 (1): 71-84. Kaplan, J.T., Iacoboni...dynamic influences on decision-making and trust during social interaction. ELICITing Behavior ELICIT is designed to explore social and cognitive ...a person’s own self-awareness in the game experience, (2) their cognitive processes of reasoning, and (3) the modulation of uncertainty that primes

The Neurodynamics of Affect in the Laboratory Predicts Persistence of Real-World Emotional Responses.

PubMed

Heller, Aaron S; Fox, Andrew S; Wing, Erik K; McQuisition, Kaitlyn M; Vack, Nathan J; Davidson, Richard J

2015-07-22

Failure to sustain positive affect over time is a hallmark of depression and other psychopathologies, but the mechanisms supporting the ability to sustain positive emotional responses are poorly understood. Here, we investigated the neural correlates associated with the persistence of positive affect in the real world by conducting two experiments in humans: an fMRI task of reward responses and an experience-sampling task measuring emotional responses to a reward obtained in the field. The magnitude of DLPFC engagement to rewards administered in the laboratory predicted reactivity of real-world positive emotion following a reward administered in the field. Sustained ventral striatum engagement in the laboratory positively predicted the duration of real-world positive emotional responses. These results suggest that common pathways are associated with the unfolding of neural processes over seconds and with the dynamics of emotions experienced over minutes. Examining such dynamics may facilitate a better understanding of the brain-behavior associations underlying emotion. Significance statement: How real-world emotion, experienced over seconds, minutes, and hours, is instantiated in the brain over the course of milliseconds and seconds is unknown. We combined a novel, real-world experience-sampling task with fMRI to examine how individual differences in real-world emotion, experienced over minutes and hours, is subserved by affective neurodynamics of brain activity over the course of seconds. When winning money in the real world, individuals sustaining positive emotion the longest were those with the most prolonged ventral striatal activity. These results suggest that common pathways are associated with the unfolding of neural processes over seconds and with the dynamics of emotions experienced over minutes. Examining such dynamics may facilitate a better understanding of the brain-behavior associations underlying emotion. Copyright © 2015 the authors 0270-6474/15/3510503-07$15.00/0.

Central sensitization does not identify patients with carpal tunnel syndrome who are likely to achieve short-term success with physical therapy.

PubMed

Fernández-de-Las-Peñas, César; Cleland, Joshua A; Ortega-Santiago, Ricardo; de-la-Llave-Rincon, Ana Isabel; Martínez-Perez, Almudena; Pareja, Juan A

2010-11-01

The aim of the current study was to identify whether hyperexcitability of the central nervous system is a prognostic factor for individuals with carpal tunnel syndrome (CTS) likely to experience rapid and clinical self-reported improvement following a physical therapy program including soft tissue mobilization and nerve slider neurodynamic interventions. Women presenting with clinical and electrophysiological findings of CTS were involved in a prospective single-arm trial. Participants underwent a standardized examination and then a physical therapy session. The physical therapy sessions included both soft tissue mobilization directed at the anatomical sites of potential median nerve entrapment and a passive nerve slider neurodynamic technique targeted to the median nerve. Pressure pain thresholds (PPT) over the median, radial and ulnar nerves, C5-C6 zygapophyseal joint, carpal tunnel and tibialis anterior muscle were assessed bilaterally. Additionally, thermal detection and pain thresholds were measured over the carpal tunnel and thenar eminence bilaterally to evaluate central nervous system excitability. Subjects were classified as responders (having achieved a successful outcome) or non-responders based on self-perceived recovery. Variables were entered into a stepwise logistic regression model to determine the most accurate variables for determining prognosis. Data from 72 women were included in the analysis, of which 35 experienced a successful outcome (48.6%). Three variables including PPT over the C5-C6 joint affected side <137 kPa, HPT carpal tunnel affected side <39.6º and general health >66 points were identified. If 2 out of 3 variables were present (LR + 14.8), the likelihood of success increased from 48.6 to 93.3%. We identified 3 factors that may be associated with a rapid clinical response to both soft tissue mobilization and nerve slider neurodynamic techniques targeted to the median nerve in women presenting with CTS. Our results support that widespread central sensitization may not be present in women with CTS who are likely to achieve a successful outcome with physical therapy. Future studies are now necessary to validate these findings.

A Randomised, Placebo-Controlled Trial of Neurodynamic Sliders on Hamstring Responses in Footballers with Hamstring Tightness

PubMed Central

Areeudomwong, Pattanasin; Oatyimprai, Ketsarakon; Pathumb, Saranchana

2016-01-01

Background Neurodynamics intervention is known to increase apparent muscle extensibility, but information regarding hamstring responses after a neurodynamic sliders (NS) technique is scarce. The aim of this study was to evaluate the effects of NS on apparent hamstring extensibility and activity in footballers with hamstring tightness. Methods Forty eligible healthy male footballers with hamstring tightness were each randomly allocated to either a 4-week NS technique or a control group (CG) receiving placebo shortwave intervention. Knee extension angles were measured with the passive knee extension test, and maximal voluntary isometric contraction (MVIC) of hamstrings was measured by a surface electromyography at baseline and after intervention sessions. Results The results showed that NS produced a statistically and clinically significant increase in knee extension angle compared to CG (P < 0.001); however, there was no difference between the groups receiving MVIC of hamstrings. Within group comparison, NS also provided a significant increase in knee extension angle (P < 0.001), whereas the control group did not. There was no change in hamstring MVIC in either group after intervention. Conclusions The findings of this study reveal that four weeks of NS technique improved apparent hamstring extensibility but did not change the hamstring activity in footballers with hamstring tightness. PMID:28090180

Effects of Thai Dancing on Median Neurodynamic Response During 4-Hour Computer Use.

PubMed

Mekhora, Keerin; Septham, Chatdao; Jalayondeja, Wattana

2015-06-01

To investigate the effects of Thai dancing on median neurodynamic response during 4-hour computer use. Twenty-four healthy participants aged 20-30 years performed 5 minutes of Thai dancing including Prom See Na, Yoong Fon Hang, Sod Soy Mala, Lor Keaw and Cha Nee Rai Mai during a 10-minute break of 4-hour computer use. All participants were assessed for nerve tension by elbow range of motion ofupper limb neurodynamic test 1 (ULNT1) and components of quick test. The discomfort was measured by visual analogue discomfort scale (VADS). These measurements were assessed before and after computer work. The statistical analyses employed paired t-test for continuous outcome and Friedman's test. The median nerve tension (indicated by elbow range of motion) was significantly reduced at before and after work, when 5 minutes of Thai dancing was introduced during the break. While components of the quick test emphasized that Thai dance immediately helped reduce the median nerve tension. The VADS in eight body areas increased over the period of 4 hours, but decreased after performing Thai dancing (p<0.05). Thai dancing helped relieve median nerve tension and body discomfort. It may be recommended as an exercise during break for computer users who continuously work to prevent WMSDs.

Manual therapy and neurodynamic mobilization in a patient with peroneal nerve paralysis: a case report.

PubMed

Villafañe, Jorge Hugo; Pillastrini, Paolo; Borboni, Alberto

2013-09-01

The purpose of this case report is to describe a therapeutic intervention for peroneal nerve paralysis involving the sciatic nerve. A 24-year-old man presented with peroneal nerve paralysis with decreased sensation, severe pain in the popliteal fossa, and steppage gait, which occurred 3 days prior to the consultation. Magnetic resonance imaging and electromyography confirmed lumbar disk herniation with sciatic common peroneal nerve entrapment in the popliteal fossa. A combined treatment protocol of spinal and fibular head manipulation and neurodynamic mobilization including soft tissue work of the psoas and hamstring muscles was performed. Outcome measures were assessed at pretreatment, 1 week posttreatment, and 3-month follow-up and included numeric pain rating scale, range of motion, pressure pain threshold, and manual muscle testing. Treatment interventions were applied for 3 sessions over a period of 1 week. Results showed reduction of the patient's subjective pain and considerable improvement in range of motion, strength, and sensation in his left foot, which was restored to full function. A combined program of spinal and fibular head manipulation and neurodynamic mobilization reduced pain, increased range of motion and strength, and restored full function to the left leg in this patient who had severe functional impairment related to a compressed left common peroneal nerve.

Learning and Adaptive Hybrid Systems for Nonlinear Control

DTIC Science & Technology

1991-05-01

34 Invention Report, S81-64, File 1, Office of Technology Liscensirig, Stanford University, 1982. [Ros62J Rosenblatt, F., Principles of Neurodynamics ...Explorations in the Microstructure of Cognition , vol. 1, Rumelhart, D., and J. McClelland, ed., MIT Press, Carbnbdge, MA, 1986. [RI-1W86] Rumnelhart, D., 0...Microstructure of Cognition , vol. 1, Rumelhart, D., and J. McClelland, ed., MIT Pres, Cambridge, MA, 1986. [Sain67] Samuel, A., "Some Studies in Machine Learning

Chaotic itinerancy in the oscillator neural network without Lyapunov functions.

PubMed

Uchiyama, Satoki; Fujisaka, Hirokazu

2004-09-01

Chaotic itinerancy (CI), which is defined as an incessant spontaneous switching phenomenon among attractor ruins in deterministic dynamical systems without Lyapunov functions, is numerically studied in the case of an oscillator neural network model. The model is the pseudoinverse-matrix version of the previous model [S. Uchiyama and H. Fujisaka, Phys. Rev. E 65, 061912 (2002)] that was studied theoretically with the aid of statistical neurodynamics. It is found that CI in neural nets can be understood as the intermittent dynamics of weakly destabilized chaotic retrieval solutions. Copyright 2004 American Institute of Physics

Neural Networks: An Overview

DTIC Science & Technology

1991-05-01

Hall, 1967. 6. Rosenblatt, F., Principles of Neurodynamics , Spartan Books, 1962. 7. Minsky, M. and Papert, S., Perceptrons, MIT Press, Revised Edition...sentations by Error Propagation, Rumelhart and McClelland (Eds.), Parallel Distributed Processing: Explorations in the Microstructure of Cognition , Vol

Function Prediction Using Recurrent Neural Networks

DTIC Science & Technology

1991-12-01

of Neurodynamics : Perceptrons and the Theory of Brain Mechanisms. Washington: Spartan Books, 1959. 16. Ruck, Dennis W. Characterization of Multilayer...Computing, 2(2) (Fall 1990). 18. Rumelhart, David E., et al. Parallel Distributed Processing: Explorations in the Microstructure of Cognition , Volume 1

Investigating Digital Optical Computing with Spatial Light Rebroadcasters

DTIC Science & Technology

1991-10-31

3303, 1991 5 5: I 66. F. Rosenblatt, Principles of neurodynamics : Perceptrons and the theory of brain mechanism, Spartan, Washington, 1961. 67. D. E...eds., Parallel Distributed Processing: Explorations in the Microstructure of Cognition , Vol-I : Foundations, MIT Press, 1986. 68. A. Ayyalusamy

Brain resting-state networks in adolescents with high-functioning autism: Analysis of spatial connectivity and temporal neurodynamics.

PubMed

Bernas, Antoine; Barendse, Evelien M; Aldenkamp, Albert P; Backes, Walter H; Hofman, Paul A M; Hendriks, Marc P H; Kessels, Roy P C; Willems, Frans M J; de With, Peter H N; Zinger, Svitlana; Jansen, Jacobus F A

2018-02-01

Autism spectrum disorder (ASD) is mainly characterized by functional and communication impairments as well as restrictive and repetitive behavior. The leading hypothesis for the neural basis of autism postulates globally abnormal brain connectivity, which can be assessed using functional magnetic resonance imaging (fMRI). Even in the absence of a task, the brain exhibits a high degree of functional connectivity, known as intrinsic, or resting-state, connectivity. Global default connectivity in individuals with autism versus controls is not well characterized, especially for a high-functioning young population. The aim of this study is to test whether high-functioning adolescents with ASD (HFA) have an abnormal resting-state functional connectivity. We performed spatial and temporal analyses on resting-state networks (RSNs) in 13 HFA adolescents and 13 IQ- and age-matched controls. For the spatial analysis, we used probabilistic independent component analysis (ICA) and a permutation statistical method to reveal the RSN differences between the groups. For the temporal analysis, we applied Granger causality to find differences in temporal neurodynamics. Controls and HFA display very similar patterns and strengths of resting-state connectivity. We do not find any significant differences between HFA adolescents and controls in the spatial resting-state connectivity. However, in the temporal dynamics of this connectivity, we did find differences in the causal effect properties of RSNs originating in temporal and prefrontal cortices. The results show a difference between HFA and controls in the temporal neurodynamics from the ventral attention network to the salience-executive network: a pathway involving cognitive, executive, and emotion-related cortices. We hypothesized that this weaker dynamic pathway is due to a subtle trigger challenging the cognitive state prior to the resting state.

Effect of leg dominance, gender and age on sensory responses to structural differentiation of straight leg raise test in asymptomatic subjects: a cross-sectional study

PubMed Central

Torres Lacomba, María; de la Villa Polo, Pedro

2017-01-01

Study design Cross-sectional study. Objectives To assess the effect of structural differentiation on sensory responses of asymptomatic individuals to standard neurodynamic tests of straight leg raise (SLR) and to evaluate the relevance of leg dominance, gender, and age. Background SLR test is a well-known neurodynamic test among physical therapists; no studies to date have investigated the influence of gender, age, and leg dominance to the sensory responses of this neurodynamic test and its structured differentiating maneuver. Methods Thirty (16 women) asymptomatic individuals enrolled in this study. Dominancy test was performed for each participant. Pain intensity using visual analogue scale (VAS), symptoms location in a body chart, nature of symptoms evoked, and hip range of motion (ROM) were recorded and compared at ankle neutral position (N-SLR) and dorsiflexion (DF-SLR) in both legs at the point of pain tolerance during SLR (P2). In addition, hip ROM was recorded at the onset of pain (P1). Results There was a statistically significant sex main effect for P1 and P2 between N-SLR and DF-SLR (p < 0.05). Mean hip ROM during the SLR was more than 10° greater in women than men. There was no statistically significant interaction between leg dominance and age group in N-SLR, DF-SLR, and VAS. Pain intensity was moderate for each SLR test. Symptoms most often described were stretch (96.7%), followed by tightness (70%) in the posterior thigh and leg. Conclusions SLR hip ROM is influenced by sex in asymptomatic individuals, leading to a greater hip ROM in SLR in women. Age and limb dominance are not relevant to SLR hip ROM or pain intensity. PMID:28559668

Numerical Analysis for Relevant Features in Intrusion Detection (NARFid)

DTIC Science & Technology

2009-03-01

Rosenblatt, Frank. Principles of Neurodynamics : Perceptrons and the Theory of Brain Mechanisms. Spartan Books, Washington DC, 1961. 74. Rossey, Lee M., Robert...editors), Parallel distributed process- ing: Explorations in the microstructure of cognition , Volume 1: Foundations. MIT Press, 1986. 76. Russel, Stuart and

Experimental analysis of chaotic neural network models for combinatorial optimization under a unifying framework.

PubMed

Kwok, T; Smith, K A

2000-09-01

The aim of this paper is to study both the theoretical and experimental properties of chaotic neural network (CNN) models for solving combinatorial optimization problems. Previously we have proposed a unifying framework which encompasses the three main model types, namely, Chen and Aihara's chaotic simulated annealing (CSA) with decaying self-coupling, Wang and Smith's CSA with decaying timestep, and the Hopfield network with chaotic noise. Each of these models can be represented as a special case under the framework for certain conditions. This paper combines the framework with experimental results to provide new insights into the effect of the chaotic neurodynamics of each model. By solving the N-queen problem of various sizes with computer simulations, the CNN models are compared in different parameter spaces, with optimization performance measured in terms of feasibility, efficiency, robustness and scalability. Furthermore, characteristic chaotic neurodynamics crucial to effective optimization are identified, together with a guide to choosing the corresponding model parameters.

Dynamic least-squares kernel density modeling of Fokker-Planck equations with application to neural population.

PubMed

Shotorban, Babak

2010-04-01

The dynamic least-squares kernel density (LSQKD) model [C. Pantano and B. Shotorban, Phys. Rev. E 76, 066705 (2007)] is used to solve the Fokker-Planck equations. In this model the probability density function (PDF) is approximated by a linear combination of basis functions with unknown parameters whose governing equations are determined by a global least-squares approximation of the PDF in the phase space. In this work basis functions are set to be Gaussian for which the mean, variance, and covariances are governed by a set of partial differential equations (PDEs) or ordinary differential equations (ODEs) depending on what phase-space variables are approximated by Gaussian functions. Three sample problems of univariate double-well potential, bivariate bistable neurodynamical system [G. Deco and D. Martí, Phys. Rev. E 75, 031913 (2007)], and bivariate Brownian particles in a nonuniform gas are studied. The LSQKD is verified for these problems as its results are compared against the results of the method of characteristics in nondiffusive cases and the stochastic particle method in diffusive cases. For the double-well potential problem it is observed that for low to moderate diffusivity the dynamic LSQKD well predicts the stationary PDF for which there is an exact solution. A similar observation is made for the bistable neurodynamical system. In both these problems least-squares approximation is made on all phase-space variables resulting in a set of ODEs with time as the independent variable for the Gaussian function parameters. In the problem of Brownian particles in a nonuniform gas, this approximation is made only for the particle velocity variable leading to a set of PDEs with time and particle position as independent variables. Solving these PDEs, a very good performance by LSQKD is observed for a wide range of diffusivities.

Monaural Speech Segregation by Integrating Primitive and Schema-Based Analysis

DTIC Science & Technology

2008-02-03

vol. 19, pp. 475-492. Wang D.L. and Chang P.S. (2008): An oscillatory correlation model of auditory streaming. Cognitive Neurodynamics , vol. 2, pp...Subcontracts DeLiang Wang (Principal Investigator) March 2008 Department of Computer Science & Engineering and Center for Cognitive Science The

Application of an Adaptive Clustering Network to Flight Control of a Fighter Aircraft. Phase 1

DTIC Science & Technology

1991-12-19

whether the underlying neurodynamics are appropriate to the dynamics of the controlled element as well as the broad objectives of the control process...Dept. of Brain & Cognitive Sciences ........................ 1 Massachusetts Institute of Technology Cambridge, MA 02139 Attn: Dr. M. Jordan Dept. of

The Harmonic Sieve: A Novel Application of Fourier Analysis to Machine Learning Theory and Practice.

DTIC Science & Technology

1995-08-23

1987. [Ros62] F. Rosenblatt. Principles of Neurodynamics : Perceptrons and the Theory of Brain Mechanisms. Spartan Books, 1962. [RHW86] D. E...editors, Parallel Distributed Processing: Explorations in the Micro structures of Cognition , volume 1, chapter 8, pages 318-362. MIT Press, 1986

Behavioral Functions of the Mesolimbic Dopaminergic System: an Affective Neuroethological Perspective

PubMed Central

Alcaro, Antonio; Huber, Robert; Panksepp, Jaak

2008-01-01

The mesolimbic dopaminergic (ML-DA) system has been recognized for its central role in motivated behaviors, various types of reward, and, more recently, in cognitive processes. Functional theories have emphasized DA's involvement in the orchestration of goal-directed behaviors, and in the promotion and reinforcement of learning. The affective neuroethological perspective presented here, views the ML-DA system in terms of its ability to activate an instinctual emotional appetitive state (SEEKING) evolved to induce organisms to search for all varieties of life-supporting stimuli and to avoid harms. A description of the anatomical framework in which the ML system is embedded is followed by the argument that the SEEKING disposition emerges through functional integration of ventral basal ganglia (BG) into thalamocortical activities. Filtering cortical and limbic input that spread into BG, DA transmission promotes the “release” of neural activity patterns that induce active SEEKING behaviors when expressed at the motor level. Reverberation of these patterns constitutes a neurodynamic process for the inclusion of cognitive and perceptual representations within the extended networks of the SEEKING urge. In this way, the SEEKING disposition influences attention, incentive salience, associative learning, and anticipatory predictions. In our view, the rewarding properties of drugs of abuse are, in part, caused by the activation of the SEEKING disposition, ranging from appetitive drive to persistent craving depending on the intensity of the affect. The implications of such a view for understanding addiction are considered, with particular emphasis on factors predisposing individuals to develop compulsive drug seeking behaviors. PMID:17905440

Behavioral functions of the mesolimbic dopaminergic system: an affective neuroethological perspective.

PubMed

Alcaro, Antonio; Huber, Robert; Panksepp, Jaak

2007-12-01

The mesolimbic dopaminergic (ML-DA) system has been recognized for its central role in motivated behaviors, various types of reward, and, more recently, in cognitive processes. Functional theories have emphasized DA's involvement in the orchestration of goal-directed behaviors and in the promotion and reinforcement of learning. The affective neuroethological perspective presented here views the ML-DA system in terms of its ability to activate an instinctual emotional appetitive state (SEEKING) evolved to induce organisms to search for all varieties of life-supporting stimuli and to avoid harms. A description of the anatomical framework in which the ML system is embedded is followed by the argument that the SEEKING disposition emerges through functional integration of ventral basal ganglia (BG) into thalamocortical activities. Filtering cortical and limbic input that spreads into BG, DA transmission promotes the "release" of neural activity patterns that induce active SEEKING behaviors when expressed at the motor level. Reverberation of these patterns constitutes a neurodynamic process for the inclusion of cognitive and perceptual representations within the extended networks of the SEEKING urge. In this way, the SEEKING disposition influences attention, incentive salience, associative learning, and anticipatory predictions. In our view, the rewarding properties of drugs of abuse are, in part, caused by the activation of the SEEKING disposition, ranging from appetitive drive to persistent craving depending on the intensity of the affect. The implications of such a view for understanding addiction are considered, with particular emphasis on factors predisposing individuals to develop compulsive drug seeking behaviors.

Neurodynamics With Spatial Self-Organization

NASA Technical Reports Server (NTRS)

Zak, Michail A.

1993-01-01

Report presents theoretical study of dynamics of neural network organizing own response in both phase space and in position space. Postulates several mathematical models of dynamics including spatial derivatives representing local interconnections among neurons. Shows how neural responses propagate via these interconnections and how spatial pattern of neural responses formed in homogeneous biological neural network.

Audiovisual Matching in Speech and Nonspeech Sounds: A Neurodynamical Model

ERIC Educational Resources Information Center

Loh, Marco; Schmid, Gabriele; Deco, Gustavo; Ziegler, Wolfram

2010-01-01

Audiovisual speech perception provides an opportunity to investigate the mechanisms underlying multimodal processing. By using nonspeech stimuli, it is possible to investigate the degree to which audiovisual processing is specific to the speech domain. It has been shown in a match-to-sample design that matching across modalities is more difficult…

Theoretical Investigation of Optical Computing Based on Neural Network Models.

DTIC Science & Technology

1987-09-29

34 Cognitive and Psychological Computation with Neu- ral Models," IEEE Trans. Sys., Man, and cyber., SMC-13, p. 799, 1983. 20’ K. Nakano, "Association-A...7),482(1986). 211 F. Rosenblatt, Principles of Neurodynamics : Perceptron and the The- ory of Brain Mechanisms, Spartan Books, Washington,(1961). 22

Feature Extraction and Classification of FLIR Imagery Using Relative Locations of Non-Homogeneous Regions with Feedforward Neural Networks

DTIC Science & Technology

1992-04-01

Proceedings of Tri-Service Data Fusion Symposium, Johns Hopkins University, May 1989. 39. F. Rosenblatt. Principles of Neurodynamics : Perceptrons and the...104 47. David E. Rummelhart and James L. McClelland. Parallel Distributed Processing: Explorations in the Microstructure of Cognition , volume 1. The

Collective neurodynamic optimization for economic emission dispatch problem considering valve point effect in microgrid.

PubMed

Wang, Tiancai; He, Xing; Huang, Tingwen; Li, Chuandong; Zhang, Wei

2017-09-01

The economic emission dispatch (EED) problem aims to control generation cost and reduce the impact of waste gas on the environment. It has multiple constraints and nonconvex objectives. To solve it, the collective neurodynamic optimization (CNO) method, which combines heuristic approach and projection neural network (PNN), is attempted to optimize scheduling of an electrical microgrid with ten thermal generators and minimize the plus of generation and emission cost. As the objective function has non-derivative points considering valve point effect (VPE), differential inclusion approach is employed in the PNN model introduced to deal with them. Under certain conditions, the local optimality and convergence of the dynamic model for the optimization problem is analyzed. The capability of the algorithm is verified in a complicated situation, where transmission loss and prohibited operating zones are considered. In addition, the dynamic variation of load power at demand side is considered and the optimal scheduling of generators within 24 h is described. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phase synchronization of neuronal noise in mouse hippocampal epileptiform dynamics.

PubMed

Serletis, Demitre; Carlen, Peter L; Valiante, Taufik A; Bardakjian, Berj L

2013-02-01

Organized brain activity is the result of dynamical, segregated neuronal signals that may be used to investigate synchronization effects using sophisticated neuroengineering techniques. Phase synchrony analysis, in particular, has emerged as a promising methodology to study transient and frequency-specific coupling effects across multi-site signals. In this study, we investigated phase synchronization in intracellular recordings of interictal and ictal epileptiform events recorded from pairs of cells in the whole (intact) mouse hippocampus. In particular, we focused our analysis on the background noise-like activity (NLA), previously reported to exhibit complex neurodynamical properties. Our results show evidence for increased linear and nonlinear phase coupling in NLA across three frequency bands [theta (4-10 Hz), beta (12-30 Hz) and gamma (30-80 Hz)] in the ictal compared to interictal state dynamics. We also present qualitative and statistical evidence for increased phase synchronization in the theta, beta and gamma frequency bands from paired recordings of ictal NLA. Overall, our results validate the use of background NLA in the neurodynamical study of epileptiform transitions and suggest that what is considered "neuronal noise" is amenable to synchronization effects in the spatiotemporal domain.

Reliability and diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression: a pilot study.

PubMed

Trainor, Kate; Pinnington, Mark A

2011-03-01

It has been proposed that neurodynamic examination can assist differential diagnosis of upper/mid lumbar nerve root compression; however, the diagnostic validity of many of these tests has yet to be established. This pilot study aimed to establish the diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression in subjects with suspected lumbosacral radicular pain. Two independent examiners performed the slump knee bend test on subjects with radicular leg pain. Inter-tester reliability was calculated using the kappa coefficient. Slump knee bend test results were compared with magnetic resonance imaging findings, and diagnostic accuracy measures were calculated including sensitivity, specificity, predictive values and likelihood ratios. Orthopaedic spinal clinic, secondary care. Sixteen patients with radicular leg pain. All four subjects with mid lumbar nerve root compression on magnetic resonance imaging were correctly identified with the slump knee bend test; however, it was falsely positive in two individuals without the condition. Inter-tester reliability for the slump knee bend test using the kappa coefficient was 0.71 (95% confidence interval 0.33 to 1.0). Diagnostic validity calculations for the slump knee bend test (95% confidence intervals) were: sensitivity, 100% (40 to 100%); specificity, 83% (52 to 98%); positive predictive value, 67% (22 to 96%); negative predictive value, 100% (69 to 100%); positive likelihood ratio, 6.0 (1.58 to 19.4); and negative likelihood ratio, 0 (0 to 0.6). Results indicate good inter-tester reliability and suggest that the slump knee bend test has potential to be a useful clinical test for identifying patients with mid lumbar nerve root compression. Further investigation is needed on larger numbers of patients to confirm these findings. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Integration of the InTime Technique in the Neurodynamic Program of Assistance to Children with Learning Disabilities

ERIC Educational Resources Information Center

Ratner, Faina Lazarevna; Efimova, Victoria Leonidovna; Efimov, Oleg Igorevich

2015-01-01

The article describes the results of application of the "inTime" neuroacoustic training by Advanced Brain Technologies (USA) when they were organizing assistance to children who had learning disabilities. This training optimizes the functional state of the brain by using sounds of various frequency and rhythm. The effectiveness of the…

Cognitive Architecture with Evolutionary Dynamics Solves Insight Problem.

PubMed

Fedor, Anna; Zachar, István; Szilágyi, András; Öllinger, Michael; de Vladar, Harold P; Szathmáry, Eörs

2017-01-01

In this paper, we show that a neurally implemented a cognitive architecture with evolutionary dynamics can solve the four-tree problem. Our model, called Darwinian Neurodynamics, assumes that the unconscious mechanism of problem solving during insight tasks is a Darwinian process. It is based on the evolution of patterns that represent candidate solutions to a problem, and are stored and reproduced by a population of attractor networks. In our first experiment, we used human data as a benchmark and showed that the model behaves comparably to humans: it shows an improvement in performance if it is pretrained and primed appropriately, just like human participants in Kershaw et al. (2013)'s experiment. In the second experiment, we further investigated the effects of pretraining and priming in a two-by-two design and found a beginner's luck type of effect: solution rate was highest in the condition that was primed, but not pretrained with patterns relevant for the task. In the third experiment, we showed that deficits in computational capacity and learning abilities decreased the performance of the model, as expected. We conclude that Darwinian Neurodynamics is a promising model of human problem solving that deserves further investigation.

Multi-AUV Target Search Based on Bioinspired Neurodynamics Model in 3-D Underwater Environments.

PubMed

Cao, Xiang; Zhu, Daqi; Yang, Simon X

2016-11-01

Target search in 3-D underwater environments is a challenge in multiple autonomous underwater vehicles (multi-AUVs) exploration. This paper focuses on an effective strategy for multi-AUV target search in the 3-D underwater environments with obstacles. First, the Dempster-Shafer theory of evidence is applied to extract information of environment from the sonar data to build a grid map of the underwater environments. Second, a topologically organized bioinspired neurodynamics model based on the grid map is constructed to represent the dynamic environment. The target globally attracts the AUVs through the dynamic neural activity landscape of the model, while the obstacles locally push the AUVs away to avoid collision. Finally, the AUVs plan their search path to the targets autonomously by a steepest gradient descent rule. The proposed algorithm deals with various situations, such as static targets search, dynamic targets search, and one or several AUVs break down in the 3-D underwater environments with obstacles. The simulation results show that the proposed algorithm is capable of guiding multi-AUV to achieve search task of multiple targets with higher efficiency and adaptability compared with other algorithms.

Cognitive Architecture with Evolutionary Dynamics Solves Insight Problem

PubMed Central

Fedor, Anna; Zachar, István; Szilágyi, András; Öllinger, Michael; de Vladar, Harold P.; Szathmáry, Eörs

2017-01-01

In this paper, we show that a neurally implemented a cognitive architecture with evolutionary dynamics can solve the four-tree problem. Our model, called Darwinian Neurodynamics, assumes that the unconscious mechanism of problem solving during insight tasks is a Darwinian process. It is based on the evolution of patterns that represent candidate solutions to a problem, and are stored and reproduced by a population of attractor networks. In our first experiment, we used human data as a benchmark and showed that the model behaves comparably to humans: it shows an improvement in performance if it is pretrained and primed appropriately, just like human participants in Kershaw et al. (2013)'s experiment. In the second experiment, we further investigated the effects of pretraining and priming in a two-by-two design and found a beginner's luck type of effect: solution rate was highest in the condition that was primed, but not pretrained with patterns relevant for the task. In the third experiment, we showed that deficits in computational capacity and learning abilities decreased the performance of the model, as expected. We conclude that Darwinian Neurodynamics is a promising model of human problem solving that deserves further investigation. PMID:28405191

Joint Data Management for MOVINT Data-to-Decision Making

DTIC Science & Technology

2011-07-01

flux tensor , aligned motion history images, and related approaches have been shown to be versatile approaches [12, 16, 17, 18]. Scaling these...methods include voting , neural networks, fuzzy logic, neuro-dynamic programming, support vector machines, Bayesian and Dempster-Shafer methods. One way...Information Fusion, 2010. [16] F. Bunyak, K. Palaniappan, S. K. Nath, G. Seetharaman, “Flux tensor constrained geodesic active contours with sensor fusion

Modeling the Neurodynamics of Submarine Piloting and Navigation Teams

DTIC Science & Technology

2014-05-07

phenomena. The Hurst exponent , H, which is commonly used in a number of scientific fields, provides an estimate of correlation overtime scales...times series for a SPAN performance and CWT representation. The CWT is superimposed by scaling exponent trend near a time of stress. Scaling... exponents at the outset correspond to corrective or anticorrelated behavior. Scaling exponents increase throughout as the team manages the incident and

The Development of a Research Environment for Neural Networks: Instantiating Neocognitions

DTIC Science & Technology

1990-12-21

interactive activation to adaptive reso- nance. Cognitive Science, 11:23-63. Reprinted in (Grossberg, 1988). Grossberg, S., editor (1988). Neural...higher order correlation network. Physica 22D, pages 276-306. Rosenblatt, F. (1962). Principles of Neurodynamics : Perceptrons and the Theory of Brain...and the PDP Research Group (1986b). Parallel Dis- tributed Processing: Ezplorations in the Microstructures of Cognition , volume 1: Foun- dations

Efficacy of Manual Therapy Including Neurodynamic Techniques for the Treatment of Carpal Tunnel Syndrome: A Randomized Controlled Trial.

PubMed

Wolny, Tomasz; Saulicz, Edward; Linek, Paweł; Shacklock, Michael; Myśliwiec, Andrzej

2017-05-01

The purpose of this randomized trial was to compare the efficacy of manual therapy, including the use of neurodynamic techniques, with electrophysical modalities on patients with mild and moderate carpal tunnel syndrome (CTS). The study included 140 CTS patients who were randomly assigned to the manual therapy (MT) group, which included the use of neurodynamic techniques, functional massage, and carpal bone mobilizations techniques, or to the electrophysical modalities (EM) group, which included laser and ultrasound therapy. Nerve conduction, pain severity, symptom severity, and functional status measured by the Boston Carpal Tunnel Questionnaire were assessed before and after treatment. Therapy was conducted twice weekly and both groups received 20 therapy sessions. A baseline assessment revealed group differences in sensory conduction of the median nerve (P < .01) but not in motor conduction (P = .82). Four weeks after the last treatment procedure, nerve conduction was examined again. In the MT group, median nerve sensory conduction velocity increased by 34% and motor conduction velocity by 6% (in both cases, P < .01). There was no change in median nerve sensory and motor conduction velocities in the EM. Distal motor latency was decreased (P < .01) in both groups. A baseline assessment revealed no group differences in pain severity, symptom severity, or functional status. Immediately after therapy, analysis of variance revealed group differences in pain severity (P < .01), with a reduction in pain in both groups (MT: 290%, P < .01; EM: 47%, P < .01). There were group differences in symptom severity (P < .01) and function (P < .01) on the Boston Carpal Tunnel Questionnaire. Both groups had an improvement in functional status (MT: 47%, P < .01; EM: 9%, P < .01) and a reduction in subjective CTS symptoms (MT: 67%, P < .01; EM: 15%, P < .01). Both therapies had a positive effect on nerve conduction, pain reduction, functional status, and subjective symptoms in individuals with CTS. However, the results regarding pain reduction, subjective symptoms, and functional status were better in the MT group. Copyright © 2017. Published by Elsevier Inc.

Dynamic Decision Making in Complex Task Environments: Principles and Neural Mechanisms

DTIC Science & Technology

2013-03-01

Dynamical models of cognition . Mathematical models of mental processes. Human performance optimization. U U U U Dr. Jay Myung 703-696-8487 Reset 1...we have continued to develop a neurodynamic theory of decision making, using a combination of computational and experimental approaches, to address...a long history in the field of human cognitive psychology. The theoretical foundations of this research can be traced back to signal detection

Evaluating the Effects of Interface Disruption Using fNIR Spectroscopy

DTIC Science & Technology

2011-02-28

Error Potentials in Brain- Computer Interfaces. ADVANCES IN COGNITIVE NEURODYNAMICS , 2008: p. 777-782. 21. Nieuwenhuis S, et al., Psychophysiology...introduced until the 1990‟s and holds great potential for extremely non-invasive cognitive state measurement. It is significantly easier and faster to...As a reminder, the general protocol is as follows: 1) Researchers gather benchmark tasks from cognitive psychology that elicit high and low

The olfactory system as the gateway to the neural correlates of consciousness

PubMed Central

Merrick, Christina; Godwin, Christine A.; Geisler, Mark W.; Morsella, Ezequiel

2014-01-01

How consciousness is generated by the nervous system remains one of the greatest mysteries in science. Investigators from diverse fields have begun to unravel this puzzle by contrasting conscious and unconscious processes. In this way, it has been revealed that the two kinds of processes differ in terms of the underlying neural events and associated cognitive mechanisms. We propose that, for several reasons, the olfactory system provides a unique portal through which to examine this contrast. For this purpose, the olfactory system is beneficial in terms of its (a) neuroanatomical aspects, (b) phenomenological and cognitive/mechanistic properties, and (c) neurodynamic (e.g., brain oscillations) properties. In this review, we discuss how each of these properties and aspects of the olfactory system can illuminate the contrast between conscious and unconscious processing in the brain. We conclude by delineating the most fruitful avenues of research and by entertaining hypotheses that, in order for an olfactory content to be conscious, that content must participate in a network that is large-scale, both in terms of the neural systems involved and the scope of information integration. PMID:24454300

A neural coding scheme reproducing foraging trajectories

NASA Astrophysics Data System (ADS)

Gutiérrez, Esther D.; Cabrera, Juan Luis

2015-12-01

The movement of many animals may follow Lévy patterns. The underlying generating neuronal dynamics of such a behavior is unknown. In this paper we show that a novel discovery of multifractality in winnerless competition (WLC) systems reveals a potential encoding mechanism that is translatable into two dimensional superdiffusive Lévy movements. The validity of our approach is tested on a conductance based neuronal model showing WLC and through the extraction of Lévy flights inducing fractals from recordings of rat hippocampus during open field foraging. Further insights are gained analyzing mice motor cortex neurons and non motor cell signals. The proposed mechanism provides a plausible explanation for the neuro-dynamical fundamentals of spatial searching patterns observed in animals (including humans) and illustrates an until now unknown way to encode information in neuronal temporal series.

Bistability induces episodic spike communication by inhibitory neurons in neuronal networks.

PubMed

Kazantsev, V B; Asatryan, S Yu

2011-09-01

Bistability is one of the important features of nonlinear dynamical systems. In neurodynamics, bistability has been found in basic Hodgkin-Huxley equations describing the cell membrane dynamics. When the neuron is clamped near its threshold, the stable rest potential may coexist with the stable limit cycle describing periodic spiking. However, this effect is often neglected in network computations where the neurons are typically reduced to threshold firing units (e.g., integrate-and-fire models). We found that the bistability may induce spike communication by inhibitory coupled neurons in the spiking network. The communication is realized in the form of episodic discharges with synchronous (correlated) spikes during the episodes. A spiking phase map is constructed to describe the synchronization and to estimate basic spike phase locking modes.

[Neurocognitive deficit and social cognition in schizophrenia].

PubMed

Rychkova, O V; Gurevich, G L

2012-01-01

To study the association between neurocognitive deficit and impairment of social cognition in schizophrenia, we assessed 30 patients and 30 healthy people (controls) using clinical, psychometric and psychological tests. Based on the results obtained in the study, authors could single out a specific block of impairment which was not associated with perceptive and gnostic deficits. The data confirmed the significant contribution of deficit neurodynamic and regulatory parameters in the impairment of social cognition in schizophrenia.

Perceptrons and Pattern Recognition

DTIC Science & Technology

1967-09-01

invariant ~isual patterns. Rosenblatt, F •. , !t_i~ip_les of Neurodynamics , Spartan Books, 1962. Introg~ces and discusses many parallel-network...classification ;of the patterns -th~selves, and their r~ cognition by per~eptrons. It· would b~ too much to ask for an absolute classification of "patt~’""’ls...function-of the level of existing cognitive structure. 0.5 Seductive Aspects of Perceptro~a, II: Parallel Computation The perceptron was conceived

Preliminary Structural Design - Defining the Design Space

DTIC Science & Technology

1993-02-01

York, 1949 7. Rosenblatt, R., Prnciples of Neurodynamics , New York, Spartan Books, 1959 8. Swift, R.,"Structural Design Using Neural Networks," Ph.D...Explorations in the Microstructure of Cognition . Vol. 1 Foundations D. E. Rumelhart and J.L. McClelland Editors, MIT Press, 1986 40. Parker, D. B...Processing: Explorations in the Microstructure of Cognition , MIT Press 1986 45. Schittkowski, K., Nonlinear o a gmi codes Lecture Notes in Economics and

Short-Term EEG Spectral Pattern as a Single Event in EEG Phenomenology

PubMed Central

Fingelkurts, Al. A; Fingelkurts, An. A

2010-01-01

Spectral decomposition, to this day, still remains the main analytical paradigm for the analysis of EEG oscillations. However, conventional spectral analysis assesses the mean characteristics of the EEG power spectra averaged out over extended periods of time and/or broad frequency bands, thus resulting in a “static” picture which cannot reflect adequately the underlying neurodynamic. A relatively new promising area in the study of EEG is based on reducing the signal to elementary short-term spectra of various types in accordance with the number of types of EEG stationary segments instead of using averaged power spectrum for the whole EEG. It is suggested that the various perceptual and cognitive operations associated with a mental or behavioural condition constitute a single distinguishable neurophysiological state with a distinct and reliable spectral pattern. In this case, one type of short-term spectral pattern may be considered as a single event in EEG phenomenology. To support this assumption the following issues are considered in detail: (a) the relations between local EEG short-term spectral pattern of particular type and the actual state of the neurons in underlying network and a volume conduction; (b) relationship between morphology of EEG short-term spectral pattern and the state of the underlying neurodynamical system i.e. neuronal assembly; (c) relation of different spectral pattern components to a distinct physiological mechanism; (d) relation of different spectral pattern components to different functional significance; (e) developmental changes of spectral pattern components; (f) heredity of the variance in the individual spectral pattern and its components; (g) intra-individual stability of the sets of EEG short-term spectral patterns and their percent ratio; (h) discrete dynamics of EEG short-term spectral patterns. Functional relevance (consistency) of EEG short-term spectral patterns in accordance with the changes of brain functional state, cognitive task and with different neuropsychopathologies is demonstrated. PMID:21379390

A neural coding scheme reproducing foraging trajectories

PubMed Central

Gutiérrez, Esther D.; Cabrera, Juan Luis

2015-01-01

The movement of many animals may follow Lévy patterns. The underlying generating neuronal dynamics of such a behavior is unknown. In this paper we show that a novel discovery of multifractality in winnerless competition (WLC) systems reveals a potential encoding mechanism that is translatable into two dimensional superdiffusive Lévy movements. The validity of our approach is tested on a conductance based neuronal model showing WLC and through the extraction of Lévy flights inducing fractals from recordings of rat hippocampus during open field foraging. Further insights are gained analyzing mice motor cortex neurons and non motor cell signals. The proposed mechanism provides a plausible explanation for the neuro-dynamical fundamentals of spatial searching patterns observed in animals (including humans) and illustrates an until now unknown way to encode information in neuronal temporal series. PMID:26648311

Achieving "organic compositionality" through self-organization: reviews on brain-inspired robotics experiments.

PubMed

Tani, Jun; Nishimoto, Ryunosuke; Paine, Rainer W

2008-05-01

The current paper examines how compositional structures can self-organize in given neuro-dynamical systems when robot agents are forced to learn multiple goal-directed behaviors simultaneously. Firstly, we propose a basic model accounting for the roles of parietal-premotor interactions for representing skills for goal-directed behaviors. The basic model had been implemented in a set of robotics experiments employing different neural network architectures. The comparative reviews among those experimental results address the issues of local vs distributed representations in representing behavior and the effectiveness of level structures associated with different sensory-motor articulation mechanisms. It is concluded that the compositional structures can be acquired "organically" by achieving generalization in learning and by capturing the contextual nature of skilled behaviors under specific conditions. Furthermore, the paper discusses possible feedback for empirical neuroscience studies in the future.

Semi-inner-products in Banach Spaces with Applications to Regularized Learning, Sampling, and Sparse Approximation

DTIC Science & Technology

2016-03-13

dynamics of percept formation modeled as operant (selectionist) process, Cognitive Neurodynamics , (08 2013): 0. doi: 10.1007/s11571-013-9262-0 Jun Zhang... cognitive principles for categorization. Our execution plan include three specific topics (“Aims”) 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13...while rooted in human cognitive principles for categorization. Our execution plan include three specific topics (“Aims”) 1. Apply RKBS theory to

A Brain-Machine-Brain Interface for Rewiring of Cortical Circuitry after Traumatic Brain Injury

DTIC Science & Technology

2014-09-01

2004. He served as Guest Coeditor of a special issue on applied neurodynamics for the Journal of Neural Engineering with Dr. Peter Thomas in December...for the millions of individuals who are left with permanent motor and cognitive impairments after acquired brain injury, as occurs in stroke and...Other investigators have proposed a closed-loop approach for a cognitive prosthesis that has shown promise in animal models (40). Other potential

Dynamic musical communication of core affect

PubMed Central

Flaig, Nicole K.; Large, Edward W.

2013-01-01

Is there something special about the way music communicates feelings? Theorists since Meyer (1956) have attempted to explain how music could stimulate varied and subtle affective experiences by violating learned expectancies, or by mimicking other forms of social interaction. Our proposal is that music speaks to the brain in its own language; it need not imitate any other form of communication. We review recent theoretical and empirical literature, which suggests that all conscious processes consist of dynamic neural events, produced by spatially dispersed processes in the physical brain. Intentional thought and affective experience arise as dynamical aspects of neural events taking place in multiple brain areas simultaneously. At any given moment, this content comprises a unified “scene” that is integrated into a dynamic core through synchrony of neuronal oscillations. We propose that (1) neurodynamic synchrony with musical stimuli gives rise to musical qualia including tonal and temporal expectancies, and that (2) music-synchronous responses couple into core neurodynamics, enabling music to directly modulate core affect. Expressive music performance, for example, may recruit rhythm-synchronous neural responses to support affective communication. We suggest that the dynamic relationship between musical expression and the experience of affect presents a unique opportunity for the study of emotional experience. This may help elucidate the neural mechanisms underlying arousal and valence, and offer a new approach to exploring the complex dynamics of the how and why of emotional experience. PMID:24672492

Dynamic musical communication of core affect.

PubMed

Flaig, Nicole K; Large, Edward W

2014-01-01

Is there something special about the way music communicates feelings? Theorists since Meyer (1956) have attempted to explain how music could stimulate varied and subtle affective experiences by violating learned expectancies, or by mimicking other forms of social interaction. Our proposal is that music speaks to the brain in its own language; it need not imitate any other form of communication. We review recent theoretical and empirical literature, which suggests that all conscious processes consist of dynamic neural events, produced by spatially dispersed processes in the physical brain. Intentional thought and affective experience arise as dynamical aspects of neural events taking place in multiple brain areas simultaneously. At any given moment, this content comprises a unified "scene" that is integrated into a dynamic core through synchrony of neuronal oscillations. We propose that (1) neurodynamic synchrony with musical stimuli gives rise to musical qualia including tonal and temporal expectancies, and that (2) music-synchronous responses couple into core neurodynamics, enabling music to directly modulate core affect. Expressive music performance, for example, may recruit rhythm-synchronous neural responses to support affective communication. We suggest that the dynamic relationship between musical expression and the experience of affect presents a unique opportunity for the study of emotional experience. This may help elucidate the neural mechanisms underlying arousal and valence, and offer a new approach to exploring the complex dynamics of the how and why of emotional experience.

Validity of the Upper Limb Neurodynamic Test 1 for the diagnosis of Carpal Tunnel Syndrome. The role of structural differentiation.

PubMed

Bueno-Gracia, Elena; Tricás-Moreno, José Miguel; Fanlo-Mazas, Pablo; Malo-Urriés, Miguel; Haddad-Garay, María; Estébanez-de-Miguel, Elena; Hidalgo-García, César; Krauss, John R

2016-04-01

Several studies have analysed the use of the Upper Limb Neurodynamic Test 1 (ULNT1) for diagnosing Carpal Tunnel Syndrome (CTS) obtaining weak diagnostic accuracy, which could be related to the lack of consensus in the selected diagnostic criteria of ULNT1. To determine the concurrent validity of ULNT1 in comparison to Nerve Conduction Studies (NCS) for the diagnosis of CTS, considering the structural differentiation (SD) as an essential part of the diagnosis. Prospective diagnostic test study. Individuals with suspected CTS referred for NCS were invited to voluntarily participate in the study. Each participant was tested with NCS and ULNT1. ULNT1 result was considered positive when the patient's clinical symptoms were reproduced during the test and symptoms changed during contralateral neck side bending (SD). 58 Participants (17 men, 44 women) with suspected CTS and a total of 95 limbs were examined using the NCS and ULNT1. Sensitivity of the ULNT1 was 57.9%, specificity was 84.2%, and the positive and negative likelihood ratios were 3.67 and 0.50 respectively. Results obtained in the study may indicate the ability of the ULNT1 to generate small shifts from pre-test to post-test probability. However, imprecision in the CIs limits interpretation from the data. 1b. Published by Elsevier Ltd.

Validity and reliability of Internet-based physiotherapy assessment for musculoskeletal disorders: a systematic review.

PubMed

Mani, Suresh; Sharma, Shobha; Omar, Baharudin; Paungmali, Aatit; Joseph, Leonard

2017-04-01

Purpose The purpose of this review is to systematically explore and summarise the validity and reliability of telerehabilitation (TR)-based physiotherapy assessment for musculoskeletal disorders. Method A comprehensive systematic literature review was conducted using a number of electronic databases: PubMed, EMBASE, PsycINFO, Cochrane Library and CINAHL, published between January 2000 and May 2015. The studies examined the validity, inter- and intra-rater reliabilities of TR-based physiotherapy assessment for musculoskeletal conditions were included. Two independent reviewers used the Quality Appraisal Tool for studies of diagnostic Reliability (QAREL) and the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool to assess the methodological quality of reliability and validity studies respectively. Results A total of 898 hits were achieved, of which 11 articles based on inclusion criteria were reviewed. Nine studies explored the concurrent validity, inter- and intra-rater reliabilities, while two studies examined only the concurrent validity. Reviewed studies were moderate to good in methodological quality. The physiotherapy assessments such as pain, swelling, range of motion, muscle strength, balance, gait and functional assessment demonstrated good concurrent validity. However, the reported concurrent validity of lumbar spine posture, special orthopaedic tests, neurodynamic tests and scar assessments ranged from low to moderate. Conclusion TR-based physiotherapy assessment was technically feasible with overall good concurrent validity and excellent reliability, except for lumbar spine posture, orthopaedic special tests, neurodynamic testa and scar assessment.

The influence of scapular depression on upper limb neurodynamic test responses

PubMed Central

Legakis, Allison; Boyd, Benjamin S

2012-01-01

Objectives Upper limb neurodynamic testing (ULNT) can be used clinically to assist in identifying neural tissue involvement in patients with upper quarter pain and dysfunction. Consideration for scapular positioning is a crucial component of ULNT standardization, as variations in positioning may dramatically impact sensory and motor responses. This study aimed to determine if there was a meaningful difference in test outcomes when the ULNT was performed in alternative scapular positions. Methods This cross-sectional study included 40 asymptomatic individuals. Repeated ULNT testing was performed on the dominant limb with the scapula blocked in neutral (ULNTb) and in scapular depression (ULNTd). Sensory responses, muscle activity, and range of motion outcomes were compared between the two test variations. Results Pre-positioning in scapular depression (ULNTd) led to reduced elbow extension range of motion, provoked greater upper trapezius muscle activity and an earlier onset and broader area of sensory responses compared to ULNTb. Discussion During ULNTb, the limbs were taken further into range and elicited reduced muscle activation and more localized sensory response providing a less vigorous version of the test. This study demonstrates that scapular positioning has a meaningful impact on ULNT test outcomes in healthy, asymptomatic individuals. The ULNTd can be considered a more vigorous version that may be appropriate when the cervical motions commonly utilized for structural differentiation are limited or contraindicated. PMID:23633886

Robust model predictive control of nonlinear systems with unmodeled dynamics and bounded uncertainties based on neural networks.

PubMed

Yan, Zheng; Wang, Jun

2014-03-01

This paper presents a neural network approach to robust model predictive control (MPC) for constrained discrete-time nonlinear systems with unmodeled dynamics affected by bounded uncertainties. The exact nonlinear model of underlying process is not precisely known, but a partially known nominal model is available. This partially known nonlinear model is first decomposed to an affine term plus an unknown high-order term via Jacobian linearization. The linearization residue combined with unmodeled dynamics is then modeled using an extreme learning machine via supervised learning. The minimax methodology is exploited to deal with bounded uncertainties. The minimax optimization problem is reformulated as a convex minimization problem and is iteratively solved by a two-layer recurrent neural network. The proposed neurodynamic approach to nonlinear MPC improves the computational efficiency and sheds a light for real-time implementability of MPC technology. Simulation results are provided to substantiate the effectiveness and characteristics of the proposed approach.

[The influence of individually fitted controlled breathing frequency on the heart rate variability indexes].

PubMed

Chuian, O M; Biriukova, O O; Ravaieva, M Iu

2010-01-01

We studied the changes in indexes of variability of heart rate and fractal neurodynamics under conditions of controlled breathing on fluctuation frequency of a spectrum of heart rate. It is shown that the controlled breathing, which frequency corresponds to a frequency of localization of the maximum peak of capacity ofa heart rate in low-frequency is a powerful mechanism of management of heart rate and change of a functional condition of an organism as a whole.

[Neurophysiologic mechanisms of combat post-extreme state of health].

PubMed

Tsygan, V N

2014-10-01

The effects of ecological and occupational stress (EOS) on brain neurodynamics of Soviet and Afghanistan servicemen have been studied. The investigations have been made in Afghanistan. Neurophysiological characteristics of traumatic stress and consequences of combat trauma were studied in patients wounded in Afghanistan, in the acute phase as well as since 0.5-3 years after leaving the battlefield. The combined effect of combat situation, hot climate, highlands and desert forms EOS. It does not cause an adaptation process in servicemen. EOS is characterized by changes in bioelectrical indices of brain in interhemispheric relations both as a whole and in isolated rhythm components of EEG, by activating the stress limiting system. It exhibits pathopsychological and autonomic components which remain significant during 3 years after leaving the combat conditions. The formation of a general adaptation syndrome is prevented in explosion trauma under the influence of EOS.

Neuronal boost to evolutionary dynamics.

PubMed

de Vladar, Harold P; Szathmáry, Eörs

2015-12-06

Standard evolutionary dynamics is limited by the constraints of the genetic system. A central message of evolutionary neurodynamics is that evolutionary dynamics in the brain can happen in a neuronal niche in real time, despite the fact that neurons do not reproduce. We show that Hebbian learning and structural synaptic plasticity broaden the capacity for informational replication and guided variability provided a neuronally plausible mechanism of replication is in place. The synergy between learning and selection is more efficient than the equivalent search by mutation selection. We also consider asymmetric landscapes and show that the learning weights become correlated with the fitness gradient. That is, the neuronal complexes learn the local properties of the fitness landscape, resulting in the generation of variability directed towards the direction of fitness increase, as if mutations in a genetic pool were drawn such that they would increase reproductive success. Evolution might thus be more efficient within evolved brains than among organisms out in the wild.

The brain's connective core and its role in animal cognition

PubMed Central

Shanahan, Murray

2012-01-01

This paper addresses the question of how the brain of an animal achieves cognitive integration—that is to say how it manages to bring its fullest resources to bear on an ongoing situation. To fully exploit its cognitive resources, whether inherited or acquired through experience, it must be possible for unanticipated coalitions of brain processes to form. This facilitates the novel recombination of the elements of an existing behavioural repertoire, and thereby enables innovation. But in a system comprising massively many anatomically distributed assemblies of neurons, it is far from clear how such open-ended coalition formation is possible. The present paper draws on contemporary findings in brain connectivity and neurodynamics, as well as the literature of artificial intelligence, to outline a possible answer in terms of the brain's most richly connected and topologically central structures, its so-called connective core. PMID:22927569

An annealed chaotic maximum neural network for bipartite subgraph problem.

PubMed

Wang, Jiahai; Tang, Zheng; Wang, Ronglong

2004-04-01

In this paper, based on maximum neural network, we propose a new parallel algorithm that can help the maximum neural network escape from local minima by including a transient chaotic neurodynamics for bipartite subgraph problem. The goal of the bipartite subgraph problem, which is an NP- complete problem, is to remove the minimum number of edges in a given graph such that the remaining graph is a bipartite graph. Lee et al. presented a parallel algorithm using the maximum neural model (winner-take-all neuron model) for this NP- complete problem. The maximum neural model always guarantees a valid solution and greatly reduces the search space without a burden on the parameter-tuning. However, the model has a tendency to converge to a local minimum easily because it is based on the steepest descent method. By adding a negative self-feedback to the maximum neural network, we proposed a new parallel algorithm that introduces richer and more flexible chaotic dynamics and can prevent the network from getting stuck at local minima. After the chaotic dynamics vanishes, the proposed algorithm is then fundamentally reined by the gradient descent dynamics and usually converges to a stable equilibrium point. The proposed algorithm has the advantages of both the maximum neural network and the chaotic neurodynamics. A large number of instances have been simulated to verify the proposed algorithm. The simulation results show that our algorithm finds the optimum or near-optimum solution for the bipartite subgraph problem superior to that of the best existing parallel algorithms.

The validity of upper-limb neurodynamic tests for detecting peripheral neuropathic pain.

PubMed

Nee, Robert J; Jull, Gwendolen A; Vicenzino, Bill; Coppieters, Michel W

2012-05-01

The validity of upper-limb neurodynamic tests (ULNTs) for detecting peripheral neuropathic pain (PNP) was assessed by reviewing the evidence on plausibility, the definition of a positive test, reliability, and concurrent validity. Evidence was identified by a structured search for peer-reviewed articles published in English before May 2011. The quality of concurrent validity studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool, where appropriate. Biomechanical and experimental pain data support the plausibility of ULNTs. Evidence suggests that a positive ULNT should at least partially reproduce the patient's symptoms and that structural differentiation should change these symptoms. Data indicate that this definition of a positive ULNT is reliable when used clinically. Limited evidence suggests that the median nerve test, but not the radial nerve test, helps determine whether a patient has cervical radiculopathy. The median nerve test does not help diagnose carpal tunnel syndrome. These findings should be interpreted cautiously, because diagnostic accuracy might have been distorted by the investigators' definitions of a positive ULNT. Furthermore, patients with PNP who presented with increased nerve mechanosensitivity rather than conduction loss might have been incorrectly classified by electrophysiological reference standards as not having PNP. The only evidence for concurrent validity of the ulnar nerve test was a case study on cubital tunnel syndrome. We recommend that researchers develop more comprehensive reference standards for PNP to accurately assess the concurrent validity of ULNTs and continue investigating the predictive validity of ULNTs for prognosis or treatment response.

M.G. Velarde: Succint Biography. Doing Science in Spain as a Maverick

NASA Astrophysics Data System (ADS)

Ryazantsev, Yu. S.

A succint account is presented about the professional career of Prof. Manuel García Velarde. Different periods illustrate his engagement with science, education and (domestic and international) organizational endeavor. The chapter also oversees some of the major areas of research he has covered with significant scientific achievements. They embrace kinetic theory, statistical mechanics, thermodynamics, fluid physics, geophysics, optics and lasers, ferromagnetism, electron transport theory, acoustics, elasticity, wave theory, reaction-diffusion science, biophysics, active lattice dynamics, and neuro-dynamics, all phenomena and methodologies treated from the unifying perspective of nonlinear dynamics.

The neuropsychology of development hemispheric laterality, limbic language, and the origin of thought.

PubMed

Joseph, R

1982-01-01

Discussed evidence and assumptions that concern hemispheric laterality and asymmetrical functional representation. It is hypothesized that the asymmetrical linguistic-motor vs. sensory-spatial-affective representation of function may be a result of differential rates of cortical, subcortical and spinal motor-sensory maturation. Evidence with regard to embryological and early postnatal neurological development is reviewed. It is argued that motor areas mature before sensory and that the left hemisphere develops prior to the right, such that the left hemisphere gains a competitive advantage in the acquisition of motor representation, whereas the later maturing right has an advantage in the establishment of sensory-affective synaptic representation, including that of limbic mediation. The influences of these differing maturational events on cognitive and psychic functioning are examined, particularly with regard to limbic influences on the development of language, thought, and mental imagery, and the effects of early emotional experience on later behavior. Thinking is viewed in part as a left hemisphere internalization of egocentric language, the internalization of which corresponds to the increasing maturation of intra-cortical and subcortical structures and fiber pathways, and the myelination of the callosal connections that subserve information transfer between the hemispheres. It is argued that thought is a means of organizing, interpreting, and explaining impulses that arise in the non-linguistic portions of the nervous system so that the language dependent regions may achieve understanding. In addition, the neurodynamics and mechanisms involved in the mislabeling, misinterpretation, and inhibition of impulses, desires, and emotional expression are discussed in relation to disturbances in psychic functioning.

Neural mechanisms of hypnosis and meditation.

PubMed

De Benedittis, Giuseppe

2015-12-01

Hypnosis has been an elusive concept for science for a long time. However, the explosive advances in neuroscience in the last few decades have provided a "bridge of understanding" between classical neurophysiological studies and psychophysiological studies. These studies have shed new light on the neural basis of the hypnotic experience. Furthermore, an ambitious new area of research is focusing on mapping the core processes of psychotherapy and the neurobiology/underlying them. Hypnosis research offers powerful techniques to isolate psychological processes in ways that allow their neural bases to be mapped. The Hypnotic Brain can serve as a way to tap neurocognitive questions and our cognitive assays can in turn shed new light on the neural bases of hypnosis. This cross-talk should enhance research and clinical applications. An increasing body of evidence provides insight in the neural mechanisms of the Meditative Brain. Discrete meditative styles are likely to target different neurodynamic patterns. Recent findings emphasize increased attentional resources activating the attentional and salience networks with coherent perception. Cognitive and emotional equanimity gives rise to an eudaimonic state, made of calm, resilience and stability, readiness to express compassion and empathy, a main goal of Buddhist practices. Structural changes in gray matter of key areas of the brain involved in learning processes suggest that these skills can be learned through practice. Hypnosis and Meditation represent two important, historical and influential landmarks of Western and Eastern civilization and culture respectively. Neuroscience has beginning to provide a better understanding of the mechanisms of both Hypnotic and Meditative Brain, outlining similarities but also differences between the two states and processes. It is important not to view either the Eastern or the Western system as superior to the other. Cross-fertilization of the ancient Eastern meditation techniques presented with Western modern clinical hypnosis will hopefully result in each enriching the other. Copyright © 2015 Elsevier Ltd. All rights reserved.

Neural learning of constrained nonlinear transformations

NASA Technical Reports Server (NTRS)

Barhen, Jacob; Gulati, Sandeep; Zak, Michail

1989-01-01

Two issues that are fundamental to developing autonomous intelligent robots, namely, rudimentary learning capability and dexterous manipulation, are examined. A powerful neural learning formalism is introduced for addressing a large class of nonlinear mapping problems, including redundant manipulator inverse kinematics, commonly encountered during the design of real-time adaptive control mechanisms. Artificial neural networks with terminal attractor dynamics are used. The rapid network convergence resulting from the infinite local stability of these attractors allows the development of fast neural learning algorithms. Approaches to manipulator inverse kinematics are reviewed, the neurodynamics model is discussed, and the neural learning algorithm is presented.

Neuronal boost to evolutionary dynamics

PubMed Central

de Vladar, Harold P.; Szathmáry, Eörs

2015-01-01

Standard evolutionary dynamics is limited by the constraints of the genetic system. A central message of evolutionary neurodynamics is that evolutionary dynamics in the brain can happen in a neuronal niche in real time, despite the fact that neurons do not reproduce. We show that Hebbian learning and structural synaptic plasticity broaden the capacity for informational replication and guided variability provided a neuronally plausible mechanism of replication is in place. The synergy between learning and selection is more efficient than the equivalent search by mutation selection. We also consider asymmetric landscapes and show that the learning weights become correlated with the fitness gradient. That is, the neuronal complexes learn the local properties of the fitness landscape, resulting in the generation of variability directed towards the direction of fitness increase, as if mutations in a genetic pool were drawn such that they would increase reproductive success. Evolution might thus be more efficient within evolved brains than among organisms out in the wild. PMID:26640653

Adaptive Self-Tuning Networks

NASA Astrophysics Data System (ADS)

Knox, H. A.; Draelos, T.; Young, C. J.; Lawry, B.; Chael, E. P.; Faust, A.; Peterson, M. G.

2015-12-01

The quality of automatic detections from seismic sensor networks depends on a large number of data processing parameters that interact in complex ways. The largely manual process of identifying effective parameters is painstaking and does not guarantee that the resulting controls are the optimal configuration settings. Yet, achieving superior automatic detection of seismic events is closely related to these parameters. We present an automated sensor tuning (AST) system that learns near-optimal parameter settings for each event type using neuro-dynamic programming (reinforcement learning) trained with historic data. AST learns to test the raw signal against all event-settings and automatically self-tunes to an emerging event in real-time. The overall goal is to reduce the number of missed legitimate event detections and the number of false event detections. Reducing false alarms early in the seismic pipeline processing will have a significant impact on this goal. Applicable both for existing sensor performance boosting and new sensor deployment, this system provides an important new method to automatically tune complex remote sensing systems. Systems tuned in this way will achieve better performance than is currently possible by manual tuning, and with much less time and effort devoted to the tuning process. With ground truth on detections in seismic waveforms from a network of stations, we show that AST increases the probability of detection while decreasing false alarms.

Neurodynamic mobilization and foam rolling improved delayed-onset muscle soreness in a healthy adult population: a randomized controlled clinical trial.

PubMed

Romero-Moraleda, Blanca; La Touche, Roy; Lerma-Lara, Sergio; Ferrer-Peña, Raúl; Paredes, Víctor; Peinado, Ana Belén; Muñoz-García, Daniel

2017-01-01

Compare the immediate effects of a Neurodynamic Mobilization (NM) treatment or foam roller (FR) treatment after DOMS. Double blind randomised clinical trial. The participants performed 100 drop jumps (5 sets of 20 repetitions, separated by 2 min rests) from a 0.5-m high box in a University biomechanics laboratory to induce muscle soreness. The participants were randomly assigned in a counter-balanced fashion to either a FR or NM treatment group. Thirty-two healthy subjects (21 males and 11 females, mean age 22.6 ± 2.2 years) were randomly assigned into the NM group ( n  = 16) or the FR group ( n  = 16). The numeric pain rating scale (NPRS; 0-10), isometric leg strength with dynamometry, surface electromyography at maximum voluntary isometric contraction (MVIC) and muscle peak activation (MPA) upon landing after a test jump were measured at baseline, 48 h after baseline before treatment, and immediately after treatment. Both groups showed significant reduction in NPRS scores after treatment (NM: 59%, p  < .01; FR: 45%, p  < .01), but no difference was found between them ( p  > .05). The percentage change improvement in the MVIC for the rectus femoris was the only significant difference between the groups ( p  < 0.05) at post-treatment. After treatment, only the FR group had a statistically significant improvement ( p  < 0.01) in strength compared to pre-treatment. Our results illustrate that both treatments are effective in reducing pain perception after DOMS whereas only FR application showed differences for the MVIC in the rectus femoris and strength.

Reliability and validity of clinical tests to assess the anatomical integrity of the cervical spine in adults with neck pain and its associated disorders: Part 1-A systematic review from the Cervical Assessment and Diagnosis Research Evaluation (CADRE) Collaboration.

PubMed

Lemeunier, Nadège; da Silva-Oolup, S; Chow, N; Southerst, D; Carroll, L; Wong, J J; Shearer, H; Mastragostino, P; Cox, J; Côté, E; Murnaghan, K; Sutton, D; Côté, P

2017-09-01

To determine the reliability and validity of clinical tests to assess the anatomical integrity of the cervical spine in adults with neck pain and its associated disorders. We updated the systematic review of the 2000-2010 Bone and Joint Decade Task Force on Neck Pain and its Associated Disorders. We also searched the literature to identify studies on the reliability and validity of Doppler velocimetry for the evaluation of cervical arteries. Two independent reviewers screened and critically appraised studies. We conducted a best evidence synthesis of low risk of bias studies and ranked the phases of investigations using the classification proposed by Sackett and Haynes. We screened 9022 articles and critically appraised 8 studies; all 8 studies had low risk of bias (three reliability and five validity Phase II-III studies). Preliminary evidence suggests that the extension-rotation test may be reliable and has adequate validity to rule out pain arising from facet joints. The evidence suggests variable reliability and preliminary validity for the evaluation of cervical radiculopathy including neurological examination (manual motor testing, dermatomal sensory testing, deep tendon reflexes, and pathological reflex testing), Spurling's and the upper limb neurodynamic tests. No evidence was found for doppler velocimetry. Little evidence exists to support the use of clinical tests to evaluate the anatomical integrity of the cervical spine in adults with neck pain and its associated disorders. We found preliminary evidence to support the use of the extension-rotation test, neurological examination, Spurling's and the upper limb neurodynamic tests.

Effects of lower limb neurodynamic mobilization on intraneural fluid dispersion of the fourth lumbar nerve root: an unembalmed cadaveric investigation

PubMed Central

Gilbert, Kerry K.; Smith, Michael P.; Sobczak, Stéphane; James, C. Roger; Sizer, Phillip S.; Brismée, Jean-Michel

2015-01-01

Objectives Manual and physical therapists incorporate neurodynamic mobilisation (NDM) to improve function and decrease pain. Little is known about the mechanisms by which these interventions affect neural tissue. The objective of this research was to assess the effects of repetitive straight leg raise (SLR) NDM on the fluid dynamics within the fourth lumbar nerve root in unembalmed cadavers. Methods A biomimetic solution (Toluidine Blue Stock 1% and Plasma) was injected intraneurally, deep to the epineurium, into the L4 nerve roots of seven unembalmed cadavers. The initial dye spread was allowed to stabilise and measured with a digital calliper. Once the initial longitudinal dye spread stabilised, an intervention strategy (repetitive SLR) was applied incorporating NDMs (stretch/relax cycles) at a rate of 30 repetitions per minute for 5 minutes. Post-intervention calliper measurements of the longitudinal dye spread were measured. Results The mean experimental posttest longitudinal dye spread measurement (1.1 ± 0.9 mm) was significantly greater (P = 0.02) than the initial stabilised pretest longitudinal dye spread measurement. Increases ranged from 0.0 to 2.6 mm and represented an average of 7.9% and up to an 18.1% increase in longitudinal dye spread. Discussion Passive NDM in the form of repetitive SLR induced a significant increase in longitudinal fluid dispersion in the L4 nerve root of human cadaveric specimen. Lower limb NDM may be beneficial in promoting nerve function by limiting or altering intraneural fluid accumulation within the nerve root, thus preventing the adverse effects of intraneural oedema. PMID:26955255

Neurodynamic responses to the femoral slump test in patients with anterior knee pain syndrome.

PubMed

Lin, Pei-Ling; Shih, Yi-Fen; Chen, Wen-Yin; Ma, Hsiao-Li

2014-05-01

Matched-control, cross-sectional study. The purpose of this study was to compare the responses to the femoral slump test (FST), including the change in hip range of motion and level of discomfort, between subjects with and without anterior knee pain. Anterior knee pain syndrome is a common problem among adults. The FST is the neurodynamic test used to assess the mechanosensitivity of the femoral component of the nervous system. However, as of yet, there is no literature discussing the use of the FST in patients with anterior knee pain. Thirty patients with anterior knee pain and 30 control participants, matched by gender, age, and dominant leg, were recruited. The subjects received the FST, during which the hip extension angle and the location and intensity of pain/discomfort were recorded. Reproduction of symptoms that were alleviated by neck extension was interpreted as a positive test. Differences in hip extension angle and pain intensity between groups were examined using a 2-way, repeated-measures analysis of variance and a Kruskal-Wallis analysis. The level of significance was set at α = .05. Subjects with anterior knee pain had a smaller hip extension angle than that of controls (-3.6° ± 5.3° versus 0.6° ± 6.1°; mean difference, 4.2°; 95% confidence interval [CI]: 1.24°, 7.15°; P = .006). Eight patients with anterior knee pain showed a positive FST, and those with a positive FST had a smaller hip extension angle (-5.7° ± 4.5°) than that of controls (mean difference, 6.3°; 95% CI: 0.8°, 11.8°; P = .007). There was no difference in the hip extension angle between the positive and negative FST groups (mean difference, 2.9°; 95% CI: -8.5°, 2.0°) or between the negative FST and control groups (mean difference, 3.4°; 95% CI: -0.4°, 7.3°). Results of this study suggest that altered mechanosensitivity of the femoral nerve occurred in the patients with anterior knee pain who presented with a positive FST. The role of increased mechanosensitivity in the development and management of anterior knee pain should be investigated in the future.

A Screening Mechanism Differentiating True from False Pain during Empathy.

PubMed

Sun, Ya-Bin; Lin, Xiao-Xiao; Ye, Wen; Wang, Ning; Wang, Jin-Yan; Luo, Fei

2017-09-13

Empathizing with another's suffering is important in social interactions. Empathic behavior is selectively elicited from genuine, meaningful pain but not from fake, meaningless scenarios. However, the brain's screening mechanism of false information from meaningful events and the time course for the screening process remains unclear. Using EEG combined with principle components analysis (PCA) techniques, here we compared temporal neurodynamics between the observation of pain and no-pain pictures as well as between true (painful expressions and needle-penetrated arms) and false (needle-penetrated faces with neutral expressions) pain pictures. The results revealed that pain vs. no-pain information is differentiated in the very early ERP components, i.e., the N1/P1 for the face and arm pictures categories and the VPP/N170 for the facial expression category while the mid-latency ERP components, N2 and P3, played key roles in differentiating true from false situations. The complex of N2 and P3 components may serve as a screening mechanism through which observers allocate their attentions to more important or relevant events and screen out false environmental information. This is the first study to describe and provide a time course of the screening process during pain empathy. These findings shed new light on the understanding of empathic processing.

Reappraising entrapment neuropathies--mechanisms, diagnosis and management.

PubMed

Schmid, Annina B; Nee, Robert J; Coppieters, Michel W

2013-12-01

The diagnosis of entrapment neuropathies can be difficult because symptoms and signs often do not follow textbook descriptions and vary significantly between patients with the same diagnosis. Signs and symptoms which spread outside of the innervation territory of the affected nerve or nerve root are common. This Masterclass provides insight into relevant mechanisms that may account for this extraterritorial spread in patients with entrapment neuropathies, with an emphasis on neuroinflammation at the level of the dorsal root ganglia and spinal cord, as well as changes in subcortical and cortical regions. Furthermore, we describe how clinical tests and technical investigations may identify these mechanisms if interpreted in the context of gain or loss of function. The management of neuropathies also remains challenging. Common treatment strategies such as joint mobilisation, neurodynamic exercises, education, and medications are discussed in terms of their potential to influence certain mechanisms at the site of nerve injury or in the central nervous system. The mechanism-oriented approach for this Masterclass seems warranted given the limitations in the current evidence for the diagnosis and management of entrapment neuropathies. Copyright © 2013 Elsevier Ltd. All rights reserved.

Self-organizing high-order cognitive functions in artificial agents: implications for possible prefrontal cortex mechanisms.

PubMed

Maniadakis, Michail; Trahanias, Panos; Tani, Jun

2012-09-01

In our daily life, we often adapt plans and behaviors according to dynamically changing world circumstances, selecting activities that make us feel more confident about the future. In this adaptation, the prefrontal cortex (PFC) is believed to have an important role, applying executive control on other cognitive processes to achieve context switching and confidence monitoring; however, many questions remain open regarding the nature of neural processes supporting executive control. The current work explores possible mechanisms of this high-order cognitive function, transferring executing control in the domain of artificial cognitive systems. In particular, we study the self-organization of artificial neural networks accomplishing a robotic rule-switching task analogous to the Wisconsin Card Sorting Test. The obtained results show that behavioral rules may be encoded in neuro-dynamic attractors, with their geometric arrangements in phase space affecting the shaping of confidence. Analysis of the emergent dynamical structures suggests possible explanations of the interactions of high-level and low-level processes in the real brain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Morphology and the gradient of a symmetric potential predict gait transitions of dogs.

PubMed

Wilshin, Simon; Haynes, G Clark; Porteous, Jack; Koditschek, Daniel; Revzen, Shai; Spence, Andrew J

2017-08-01

Gaits and gait transitions play a central role in the movement of animals. Symmetry is thought to govern the structure of the nervous system, and constrain the limb motions of quadrupeds. We quantify the symmetry of dog gaits with respect to combinations of bilateral, fore-aft, and spatio-temporal symmetry groups. We tested the ability of symmetries to model motion capture data of dogs walking, trotting and transitioning between those gaits. Fully symmetric models performed comparably to asymmetric with only a [Formula: see text] increase in the residual sum of squares and only one-quarter of the parameters. This required adding a spatio-temporal shift representing a lag between fore and hind limbs. Without this shift, the symmetric model residual sum of squares was [Formula: see text] larger. This shift is related to (linear regression, [Formula: see text], [Formula: see text]) dog morphology. That this symmetry is respected throughout the gaits and transitions indicates that it generalizes outside a single gait. We propose that relative phasing of limb motions can be described by an interaction potential with a symmetric structure. This approach can be extended to the study of interaction of neurodynamic and kinematic variables, providing a system-level model that couples neuronal central pattern generator networks and mechanical models.

A systems medicine research approach for studying alcohol addiction.

PubMed

Spanagel, Rainer; Durstewitz, Daniel; Hansson, Anita; Heinz, Andreas; Kiefer, Falk; Köhr, Georg; Matthäus, Franziska; Nöthen, Markus M; Noori, Hamid R; Obermayer, Klaus; Rietschel, Marcella; Schloss, Patrick; Scholz, Henrike; Schumann, Gunter; Smolka, Michael; Sommer, Wolfgang; Vengeliene, Valentina; Walter, Henrik; Wurst, Wolfgang; Zimmermann, Uli S; Stringer, Sven; Smits, Yannick; Derks, Eske M

2013-11-01

According to the World Health Organization, about 2 billion people drink alcohol. Excessive alcohol consumption can result in alcohol addiction, which is one of the most prevalent neuropsychiatric diseases afflicting our society today. Prevention and intervention of alcohol binging in adolescents and treatment of alcoholism are major unmet challenges affecting our health-care system and society alike. Our newly formed German SysMedAlcoholism consortium is using a new systems medicine approach and intends (1) to define individual neurobehavioral risk profiles in adolescents that are predictive of alcohol use disorders later in life and (2) to identify new pharmacological targets and molecules for the treatment of alcoholism. To achieve these goals, we will use omics-information from epigenomics, genetics transcriptomics, neurodynamics, global neurochemical connectomes and neuroimaging (IMAGEN; Schumann et al. ) to feed mathematical prediction modules provided by two Bernstein Centers for Computational Neurosciences (Berlin and Heidelberg/Mannheim), the results of which will subsequently be functionally validated in independent clinical samples and appropriate animal models. This approach will lead to new early intervention strategies and identify innovative molecules for relapse prevention that will be tested in experimental human studies. This research program will ultimately help in consolidating addiction research clusters in Germany that can effectively conduct large clinical trials, implement early intervention strategies and impact political and healthcare decision makers. © 2013 Society for the Study of Addiction.

Multimodal interactions in typically and atypically developing children: natural versus artificial environments.

PubMed

Giannopulu, Irini

2013-11-01

This review addresses the central role played by multimodal interactions in neurocognitive development. We first analyzed our studies of multimodal verbal and nonverbal cognition and emotional interactions within neuronal, that is, natural environments in typically developing children. We then tried to relate them to the topic of creating artificial environments using mobile toy robots to neurorehabilitate severely autistic children. By doing so, both neural/natural and artificial environments are considered as the basis of neuronal organization and reorganization. The common thread underlying the thinking behind this approach revolves around the brain's intrinsic properties: neuroplasticity and the fact that the brain is neurodynamic. In our approach, neural organization and reorganization using natural or artificial environments aspires to bring computational perspectives into cognitive developmental neuroscience.

The SEEKING mind: primal neuro-affective substrates for appetitive incentive states and their pathological dynamics in addictions and depression.

PubMed

Alcaro, Antonio; Panksepp, Jaak

2011-10-01

Appetitive motivation and incentive states are essential functions sustained by a common emotional brain process, the SEEKING disposition, which drives explorative and approach behaviors, sustains goal-directed activity, promotes anticipatory cognitions, and evokes feelings of positive excitement which control reward-learning. All such functions are orchestrated by the same "archetypical" neural processes, activated in ancient subcortical areas and transported to the forebrain by the mesolimbic dopamine (ML-DA) system. In mammals, the neurophysiology of the SEEKING urge is expressed by DA-promoted high-frequency oscillations, in the form of transient and synchronized gamma waves (>30Hz) emerging in limbic forebrain and diffusing throughout basal ganglia-thalamocortical (BG-T-C) circuits. These patterns may be considered basic "SEEKING neurodynamic impulses" which represent the primary-process exploratory disposition getting integrated with information relative to the external and the internal environment. Abnormal manifestation of SEEKING and its neural substrates are evident in clinical depression and addiction. Specifically, depression is characterized by reduced recruitment of SEEKING, while addictions reflect re-organizations of the SEEKING disposition around ultra-specific appetitive memories and compulsive activities. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comparing the Cognitive Process of Circular Causality in Two Patients with Strokes through Qualitative Analysis.

PubMed

Derakhshanrad, Seyed Alireza; Piven, Emily; Ghoochani, Bahareh Zeynalzadeh

2017-10-01

Walter J. Freeman pioneered the neurodynamic model of brain activity when he described the brain dynamics for cognitive information transfer as the process of circular causality at intention, meaning, and perception (IMP) levels. This view contributed substantially to establishment of the Intention, Meaning, and Perception Model of Neuro-occupation in occupational therapy. As described by the model, IMP levels are three components of the brain dynamics system, with nonlinear connections that enable cognitive function to be processed in a circular causality fashion, known as Cognitive Process of Circular Causality (CPCC). Although considerable research has been devoted to study the brain dynamics by sophisticated computerized imaging techniques, less attention has been paid to study it through investigating the adaptation process of thoughts and behaviors. To explore how CPCC manifested thinking and behavioral patterns, a qualitative case study was conducted on two matched female participants with strokes, who were of comparable ages, affected sides, and other characteristics, except for their resilience and motivational behaviors. CPCC was compared by matrix analysis between two participants, using content analysis with pre-determined categories. Different patterns of thinking and behavior may have happened, due to disparate regulation of CPCC between two participants.

Capture of fixation by rotational flow; a deterministic hypothesis regarding scaling and stochasticity in fixational eye movements

PubMed Central

Wilkinson, Nicholas M.; Metta, Giorgio

2014-01-01

Visual scan paths exhibit complex, stochastic dynamics. Even during visual fixation, the eye is in constant motion. Fixational drift and tremor are thought to reflect fluctuations in the persistent neural activity of neural integrators in the oculomotor brainstem, which integrate sequences of transient saccadic velocity signals into a short term memory of eye position. Despite intensive research and much progress, the precise mechanisms by which oculomotor posture is maintained remain elusive. Drift exhibits a stochastic statistical profile which has been modeled using random walk formalisms. Tremor is widely dismissed as noise. Here we focus on the dynamical profile of fixational tremor, and argue that tremor may be a signal which usefully reflects the workings of oculomotor postural control. We identify signatures reminiscent of a certain flavor of transient neurodynamics; toric traveling waves which rotate around a central phase singularity. Spiral waves play an organizational role in dynamical systems at many scales throughout nature, though their potential functional role in brain activity remains a matter of educated speculation. Spiral waves have a repertoire of functionally interesting dynamical properties, including persistence, which suggest that they could in theory contribute to persistent neural activity in the oculomotor postural control system. Whilst speculative, the singularity hypothesis of oculomotor postural control implies testable predictions, and could provide the beginnings of an integrated dynamical framework for eye movements across scales. PMID:24616670

Neurodynamic evaluation of hearing aid features using EEG correlates of listening effort.

PubMed

Bernarding, Corinna; Strauss, Daniel J; Hannemann, Ronny; Seidler, Harald; Corona-Strauss, Farah I

2017-06-01

In this study, we propose a novel estimate of listening effort using electroencephalographic data. This method is a translation of our past findings, gained from the evoked electroencephalographic activity, to the oscillatory EEG activity. To test this technique, electroencephalographic data from experienced hearing aid users with moderate hearing loss were recorded, wearing hearing aids. The investigated hearing aid settings were: a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off, and a setting using omnidirectional microphones without any noise reduction. The results suggest that the electroencephalographic estimate of listening effort seems to be a useful tool to map the exerted effort of the participants. In addition, the results indicate that a directional processing mode can reduce the listening effort in multitalker listening situations.

Solving large scale traveling salesman problems by chaotic neurodynamics.

PubMed

Hasegawa, Mikio; Ikeguch, Tohru; Aihara, Kazuyuki

2002-03-01

We propose a novel approach for solving large scale traveling salesman problems (TSPs) by chaotic dynamics. First, we realize the tabu search on a neural network, by utilizing the refractory effects as the tabu effects. Then, we extend it to a chaotic neural network version. We propose two types of chaotic searching methods, which are based on two different tabu searches. While the first one requires neurons of the order of n2 for an n-city TSP, the second one requires only n neurons. Moreover, an automatic parameter tuning method of our chaotic neural network is presented for easy application to various problems. Last, we show that our method with n neurons is applicable to large TSPs such as an 85,900-city problem and exhibits better performance than the conventional stochastic searches and the tabu searches.

Effects of noise on a computational model for disease states of mood disorders

NASA Astrophysics Data System (ADS)

Tobias Huber, Martin; Krieg, Jürgen-Christian; Braun, Hans Albert; Moss, Frank

2000-03-01

Nonlinear dynamics are currently proposed to explain the progressive course of recurrent mood disorders starting with isolated episodes and ending with accelerated irregular (``chaotic") mood fluctuations. Such a low-dimensional disease model is attractive because of its principal accordance with biological disease models, i.e. the kindling and biological rhythms model. However, most natural systems are nonlinear and noisy and several studies in the neuro- and physical sciences have demonstrated interesting cooperative behaviors arising from interacting random and deterministic dynamics. Here, we consider the effects of noise on a recent neurodynamical model for the timecourse of affective disorders (Huber et al.: Biological Psychiatry 1999;46:256-262). We describe noise effects on temporal patterns and mean episode frequencies of various in computo disease states. Our simulations demonstrate that noise can cause unstructured randomness or can maximize periodic order. The frequency of episode occurence can increase with noise but it can also remain unaffected or even can decrease. We show further that noise can make visible bifurcations before they would normally occur under deterministic conditions and we quantify this behavior with a recently developed statistical method. All these effects depend critically on both, the dynamic state and the noise intensity. Implications for neurobiology and course of mood disorders are discussed.

Neurodynamic oscillators

NASA Technical Reports Server (NTRS)

Espinosa, Ismael; Gonzalez, Hortensia; Quiza, Jorge; Gonazalez, J. Jesus; Arroyo, Ruben; Lara, Ritaluz

1995-01-01

Oscillation of electrical activity has been found in many nervous systems, from invertebrates to vertebrates including man. There exists experimental evidence of very simple circuits with the capability of oscillation. Neurons with intrinsic oscillation have been found and also neural circuits where oscillation is a property of the network. These two types of oscillations coexist in many instances. It is nowadays hypothesized that behind synchronization and oscillation there is a system of coupled oscillators responsible for activities that range from locomotion and feature binding in vision to control of sleep and circadian rhythms. The huge knowledge that has been acquired on oscillators from the times of Lord Rayleigh has made the simulation of neural oscillators a very active endeavor. This has been enhanced with more recent physiological findings about small neural circuits by means of intracellular and extracellular recordings as well as imaging methods. The future of this interdisciplinary field looks very promising; some researchers are going into quantum mechanics with the idea of trying to provide a quantum description of the brain. In this work we describe some simulations using neuron models by means of which we form simple neural networks that have the capability of oscillation. We analyze the oscillatory activity with root locus method, cross-correlation histograms, and phase planes. In the more complicated neural network models there is the possibility of chaotic oscillatory activity and we study that by means of Lyapunov exponents. The companion paper shows an example of that kind.

Willed action, free will, and the stochastic neurodynamics of decision-making

PubMed Central

Rolls, Edmund T.

2012-01-01

It is shown that the randomness of the firing times of neurons in decision-making attractor neuronal networks that is present before the decision cues are applied can cause statistical fluctuations that influence the decision that will be taken. In this rigorous sense, it is possible to partially predict decisions before they are made. This raises issues about free will and determinism. There are many decision-making networks in the brain. Some decision systems operate to choose between gene-specified rewards such as taste, touch, and beauty (in for example the peacock's tail). Other processes capable of planning ahead with multiple steps held in working memory may require correction by higher order thoughts that may involve explicit, conscious, processing. The explicit system can allow the gene-specified rewards not to be selected or deferred. The decisions between the selfish gene-specified rewards, and the explicitly calculated rewards that are in the interests of the individual, the phenotype, may themselves be influenced by noise in the brain. When the explicit planning system does take the decision, it can report on its decision-making, and can provide a causal account rather than a confabulation about the decision process. We might use the terms “willed action” and “free will” to refer to the operation of the planning system that can think ahead over several steps held in working memory with which it can take explicit decisions. Reduced connectivity in some of the default mode cortical regions including the precuneus that are active during self-initiated action appears to be related to the reduction in the sense of self and agency, of causing willed actions, that can be present in schizophrenia. PMID:22973205

Putting reins on the brain. How the body and environment use it

PubMed Central

Dotov, Dobromir G.

2014-01-01

Radical embodied cognitive neuroscience (RECN) will probably rely on dynamical systems theory (DST) and complex systems theory for methods and formalism. Yet, there have been plenty of non-radical neurodynamicists out there for quite some time. How much of their work fits with radical embodied cognitive science, what do they need RECN for, and what are the inconsistencies between RECN and established neurodynamics that would have to be resolved? This paper is both theoretical hypothesis and review. First, it provides a brief overview of the typical, purely structural considerations why the central nervous systems (CNS) should be treated as a nonlinear dynamical system and what this entails. The reader will learn about the circular causality enclosing brain and behavior and different attempts to formalize this circularity. Then, three different attempts at linking dynamics and theory of brain function are described in more detail and criticized. A fourth method based on ecological psychology could fix some of the issues that the others encounter. It is argued that studying self-organization of the brain without taking its ecological embedding into account is insufficient. Finally, based on existing theoretical work we propose two roles that the CNS has to be fulfilling in order to allow an animal to behave adequately in its niche. In its first role the CNS has to be enslaved easily by patterns of behavior that guide the animal through its environment. In the second role the brain has to flexibly switch among patterns, what can be called the metastable circuit breaker. The relevance of this idea is supported using certain motor symptoms of Parkinson’s disease (PD). These symptoms can be explained as consequent to an excessive stability of the (metastable) circuit breaker. PMID:25346675

Spontaneous tempo and rhythmic entrainment in a bonobo (Pan paniscus).

PubMed

Large, Edward W; Gray, Patricia M

2015-11-01

The emergence of speech and music in the human species represent major evolutionary transitions that enabled the use of complex, temporally structured acoustic signals to coordinate social interaction. While the fundamental capacity for temporal coordination with complex acoustic signals has been shown in a few distantly related species, the extent to which nonhuman primates exhibit sensitivity to auditory rhythms remains controversial. In Experiment 1, we assessed spontaneous motor tempo and tempo matching in a bonobo (Pan paniscus), in the context of a social drumming interaction. In Experiment 2, the bonobo spontaneously entrained and synchronized her drum strikes within a range around her spontaneous motor tempo. Our results are consistent with the hypothesis that the evolution of acoustic communication builds upon fundamental neurodynamic mechanisms that can be found in a wide range of species, and are recruited for social interactions. (c) 2015 APA, all rights reserved).

Analysis of electromyographic activity in spastic biceps brachii muscle following neural mobilization.

PubMed

Castilho, Jéssica; Ferreira, Luiz Alfredo Braun; Pereira, Wagner Menna; Neto, Hugo Pasini; Morelli, José Geraldo da Silva; Brandalize, Danielle; Kerppers, Ivo Ilvan; Oliveira, Claudia Santos

2012-07-01

Hypertonia is prevalent in anti-gravity muscles, such as the biceps brachii. Neural mobilization is one of the techniques currently used to reduce spasticity. The aim of the present study was to assess electromyographic (EMG) activity in spastic biceps brachii muscles before and after neural mobilization of the upper limb contralateral to the hemiplegia. Repeated pre-test and post-test EMG measurements were performed on six stroke victims with grade 1 or 2 spasticity (Modified Ashworth Scale). The Upper Limb Neurodynamic Test (ULNT1) was the mobilization technique employed. After neural mobilization contralateral to the lesion, electromyographic activity in the biceps brachii decreased by 17% and 11% for 90° flexion and complete extension of the elbow, respectively. However, the results were not statistically significant (p gt; 0.05). When performed using contralateral techniques, neural mobilization alters the electrical signal of spastic muscles. Copyright © 2011 Elsevier Ltd. All rights reserved.

Recurrent hamstring muscle injury: applying the limited evidence in the professional football setting with a seven-point programme

PubMed Central

Brukner, Peter; Nealon, Andrew; Morgan, Christopher; Burgess, Darren; Dunn, Andrew

2014-01-01

Recurrent hamstring injuries are a major problem in sports such as football. The aim of this paper was to use a clinical example to describe a treatment strategy for the management of recurrent hamstring injuries and examine the evidence for each intervention. A professional footballer sustained five hamstring injuries in a relatively short period of time. The injury was managed successfully with a seven-point programme—biomechanical assessment and correction, neurodynamics, core stability, eccentric strengthening, an overload running programme, injection therapies and stretching/relaxation. The evidence for each of these treatment options is reviewed. It is impossible to be definite about which aspects of the programme contributed to a successful outcome. Only limited evidence is available in most cases; therefore, decisions regarding the use of different treatment modalities must be made by using a combination of clinical experience and research evidence. PMID:23322894

The neuronal dynamics underlying cognitive flexibility in set shifting tasks.

PubMed

Stemme, Anja; Deco, Gustavo; Busch, Astrid

2007-12-01

The ability to switch attention from one aspect of an object to another or in other words to switch the "attentional set" as investigated in tasks like the "Wisconsin Card Sorting Test" is commonly referred to as cognitive flexibility. In this work we present a biophysically detailed neurodynamical model which illustrates the neuronal base of the processes related to this cognitive flexibility. For this purpose we conducted behavioral experiments which allow the combined evaluation of different aspects of set shifting tasks: uninstructed set shifts as investigated in Wisconsin-like tasks, effects of stimulus congruency as investigated in Stroop-like tasks and the contribution of working memory as investigated in "Delayed-Match-to-Sample" tasks. The work describes how general experimental findings are usable to design the architecture of a biophysical detailed though minimalistic model with a high orientation on neurobiological findings and how, in turn, the simulations support experimental investigations. The resulting model is able to account for experimental and individual response times and error rates and enables the switch of attention as a system inherent model feature: The switching process suggested by the model is based on the memorization of the visual stimuli and does not require any synaptic learning. The operation of the model thus demonstrates with at least a high probability the neuronal dynamics underlying a key component of human behavior: the ability to adapt behavior according to context requirements--cognitive flexibility.

Statistical similarities of pre-earthquake electromagnetic emissions to biological and economic extreme events

NASA Astrophysics Data System (ADS)

Potirakis, Stelios M.; Contoyiannis, Yiannis; Kopanas, John; Kalimeris, Anastasios; Antonopoulos, George; Peratzakis, Athanasios; Eftaxias, Konstantinos; Nomicos, Costantinos

2014-05-01

When one considers a phenomenon that is "complex" refers to a system whose phenomenological laws that describe the global behavior of the system, are not necessarily directly related to the "microscopic" laws that regulate the evolution of its elementary parts. The field of study of complex systems considers that the dynamics of complex systems are founded on universal principles that may be used to describe disparate problems ranging from particle physics to economies of societies. Several authors have suggested that earthquake (EQ) dynamics can be analyzed within similar mathematical frameworks with economy dynamics, and neurodynamics. A central property of the EQ preparation process is the occurrence of coherent large-scale collective behavior with a very rich structure, resulting from repeated nonlinear interactions among the constituents of the system. As a result, nonextensive statistics is an appropriate, physically meaningful, tool for the study of EQ dynamics. Since the fracture induced electromagnetic (EM) precursors are observable manifestations of the underlying EQ preparation process, the analysis of a fracture induced EM precursor observed prior to the occurrence of a large EQ can also be conducted within the nonextensive statistics framework. Within the frame of the investigation for universal principles that may hold for different dynamical systems that are related to the genesis of extreme events, we present here statistical similarities of the pre-earthquake EM emissions related to an EQ, with the pre-ictal electrical brain activity related to an epileptic seizure, and with the pre-crisis economic observables related to the collapse of a share. It is demonstrated the all three dynamical systems' observables can be analyzed in the frame of nonextensive statistical mechanics, while the frequency-size relations of appropriately defined "events" that precede the extreme event related to each one of these different systems present striking quantitative similarities. It is also demonstrated that, for the considered systems, the nonextensive parameter q increases as the extreme event approaches, which indicates that the strength of the long-memory / long-range interactions between the constituents of the system increases characterizing the dynamics of the system.

Control and Synchronization of Heteroclinic Chaos: Implications for Neurodynamics

NASA Astrophysics Data System (ADS)

Arecchi, F. Tito

2004-12-01

Heteroclinic chaos (HC) implies the recurrent return of the dynamical trajectory to a saddle focus (SF) in whose neighborhood the system response to an external perturbation is very high and hence it is very easy to lock to an external stimulus. Thus HC appears as the easiest way to encode information in time by a train of equal spikes occurring at erratic times. Implementing such a dynamics with a single mode CO2 laser with feedback, we have a heteroclinic connection between the SF and a saddle node (SN) whose role it to regularize the phase space orbit away from SF. Due to these two different fixed points, the laser intensity displays identical spikes separated by erratic ISIs (interspike intervals). Such a dynamics is highly prone to spike-synchronization, either by an external signal or by mutual interaction in a network of identical systems. Applications to communication and noise induced synchronization will be reported. In experimental neuroscience a recent finding is that feature binding ,that is, combination of external stimuli with internal memories into new coherent patterns of meaning, implies the mutual synchronization of axonal spike trains in neurons which can be far away and yet share the same sequence. Several dynamical systems have been proposed to model such a behavior. We introduce a measurable parameter, namely, the synchronization "propensity". Propensity is the amount of synchronization achieved in a chaotic system by a small sinusoidal perturbation of a control parameter. It is very low for coupled Lorenz or FitzHugh-Nagumo chains. It displays isolated peaks for the Hindmarsh-Rose model, showing that this is a convenient description of the bursting behavior typical of neurons in the CPG (central pattern generator) system. Instead, HC shows a high propensity over a wide input frequency range, demonstrating that it is the most convenient model for semantic neurons.

Deconstructing the “Resting” State: Exploring the Temporal Dynamics of Frontal Alpha Asymmetry as an Endophenotype for Depression

PubMed Central

Allen, John J. B.; Cohen, Michael X

2010-01-01

Asymmetry in frontal electrocortical alpha-band (8–13 Hz) activity recorded during resting situations (i.e., in absence of a specific task) has been investigated in relation to emotion and depression for over 30 years. This asymmetry reflects an aspect of endogenous cortical dynamics that is stable over repeated measurements and that may serve as an endophenotype for mood or other psychiatric disorders. In nearly all of this research, EEG activity is averaged across several minutes, obscuring transient dynamics that unfold on the scale of milliseconds to seconds. Such dynamic states may ultimately have greater value in linking brain activity to surface EEG asymmetry, thus improving its status as an endophenotype for depression. Here we introduce novel metrics for characterizing frontal alpha asymmetry that provide a more in-depth neurodynamical understanding of recurrent endogenous cortical processes during the resting-state. The metrics are based on transient “bursts” of asymmetry that occur frequently during the resting-state. In a sample of 306 young adults, 143 with a lifetime diagnosis of major depressive disorder (62 currently symptomatic), three questions were addressed: (1) How do novel peri-burst metrics of dynamic asymmetry compare to conventional fast-Fourier transform-based metrics? (2) Do peri-burst metrics adequately differentiate depressed from non-depressed participants? and, (3) what EEG dynamics surround the asymmetry bursts? Peri-burst metrics correlated with traditional measures of asymmetry, and were sensitive to both current and past episodes of major depression. Moreover, asymmetry bursts were characterized by a transient lateralized alpha suppression that is highly consistent in phase across bursts, and a concurrent contralateral transient alpha enhancement that is less tightly phase-locked across bursts. This approach opens new possibilities for investigating rapid cortical dynamics during resting-state EEG. PMID:21228910

Dissipation of ‘dark energy’ by cortex in knowledge retrieval

NASA Astrophysics Data System (ADS)

Capolupo, Antonio; Freeman, Walter J.; Vitiello, Giuseppe

2013-03-01

We have devised a thermodynamic model of cortical neurodynamics expressed at the classical level by neural networks and at the quantum level by dissipative quantum field theory. Our model is based on features in the spatial images of cortical activity newly revealed by high-density electrode arrays. We have incorporated the mechanism and necessity for so-called dark energy in knowledge retrieval. We have extended the model first using the Carnot cycle to define our measures for energy, entropy and temperature, and then using the Rankine cycle to incorporate criticality and phase transitions. We describe the dynamics of two interactive fields of neural activity that express knowledge, one at high and the other at low energy density, and the two operators that create and annihilate the fields. We postulate that the extremely high density of energy sequestered briefly in cortical activity patterns can account for the vividness, richness of associations, and emotional intensity of memories recalled by stimuli.

Dreaming of mathematical neuroscience for half a century.

PubMed

Amari, Shun-ichi

2013-01-01

Theoreticians have been enchanted by the secrets of the brain for many years: how and why does it work so well? There has been a long history of searching for its mechanisms. Theoretical or even mathematical scientists have proposed various models of neural networks which has led to the birth of a new field of research. We can think of the 'pre-historic' period of Rashevski and Wiener, and then the period of perceptrons which is the beginning of learning machines, neurodynamics approaches, and further connectionist approaches. Now is currently the period of computational neuroscience. I have been working in this field for nearly half a century, and have experienced its repeated rise and fall. Now having reached very old age, I would like to state my own endeavors on establishing mathematical neuroscience for half a century, from a personal, even biased, point of view. It would be my pleasure if my experiences could encourage young researchers to participate in mathematical neuroscience. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dissipation of 'dark energy' by cortex in knowledge retrieval.

PubMed

Capolupo, Antonio; Freeman, Walter J; Vitiello, Giuseppe

2013-03-01

We have devised a thermodynamic model of cortical neurodynamics expressed at the classical level by neural networks and at the quantum level by dissipative quantum field theory. Our model is based on features in the spatial images of cortical activity newly revealed by high-density electrode arrays. We have incorporated the mechanism and necessity for so-called dark energy in knowledge retrieval. We have extended the model first using the Carnot cycle to define our measures for energy, entropy and temperature, and then using the Rankine cycle to incorporate criticality and phase transitions. We describe the dynamics of two interactive fields of neural activity that express knowledge, one at high and the other at low energy density, and the two operators that create and annihilate the fields. We postulate that the extremely high density of energy sequestered briefly in cortical activity patterns can account for the vividness, richness of associations, and emotional intensity of memories recalled by stimuli. Copyright © 2013 Elsevier B.V. All rights reserved.

Dynamics of the brain: Mathematical models and non-invasive experimental studies

NASA Astrophysics Data System (ADS)

Toronov, V.; Myllylä, T.; Kiviniemi, V.; Tuchin, V. V.

2013-10-01

Dynamics is an essential aspect of the brain function. In this article we review theoretical models of neural and haemodynamic processes in the human brain and experimental non-invasive techniques developed to study brain functions and to measure dynamic characteristics, such as neurodynamics, neurovascular coupling, haemodynamic changes due to brain activity and autoregulation, and cerebral metabolic rate of oxygen. We focus on emerging theoretical biophysical models and experimental functional neuroimaging results, obtained mostly by functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS). We also included our current results on the effects of blood pressure variations on cerebral haemodynamics and simultaneous measurements of fast processes in the brain by near-infrared spectroscopy and a very novel functional MRI technique called magnetic resonance encephalography. Based on a rapid progress in theoretical and experimental techniques and due to the growing computational capacities and combined use of rapidly improving and emerging neuroimaging techniques we anticipate during next decade great achievements in the overall knowledge of the human brain.

Breeding novel solutions in the brain: a model of Darwinian neurodynamics.

PubMed

Szilágyi, András; Zachar, István; Fedor, Anna; de Vladar, Harold P; Szathmáry, Eörs

2016-01-01

Background : The fact that surplus connections and neurons are pruned during development is well established. We complement this selectionist picture by a proof-of-principle model of evolutionary search in the brain, that accounts for new variations in theory space. We present a model for Darwinian evolutionary search for candidate solutions in the brain. Methods : We combine known components of the brain - recurrent neural networks (acting as attractors), the action selection loop and implicit working memory - to provide the appropriate Darwinian architecture. We employ a population of attractor networks with palimpsest memory. The action selection loop is employed with winners-share-all dynamics to select for candidate solutions that are transiently stored in implicit working memory. Results : We document two processes: selection of stored solutions and evolutionary search for novel solutions. During the replication of candidate solutions attractor networks occasionally produce recombinant patterns, increasing variation on which selection can act. Combinatorial search acts on multiplying units (activity patterns) with hereditary variation and novel variants appear due to (i) noisy recall of patterns from the attractor networks, (ii) noise during transmission of candidate solutions as messages between networks, and, (iii) spontaneously generated, untrained patterns in spurious attractors. Conclusions : Attractor dynamics of recurrent neural networks can be used to model Darwinian search. The proposed architecture can be used for fast search among stored solutions (by selection) and for evolutionary search when novel candidate solutions are generated in successive iterations. Since all the suggested components are present in advanced nervous systems, we hypothesize that the brain could implement a truly evolutionary combinatorial search system, capable of generating novel variants.

Accuracy of clinical neurological examination in diagnosing lumbo-sacral radiculopathy: a systematic literature review.

PubMed

Tawa, Nassib; Rhoda, Anthea; Diener, Ina

2017-02-23

Lumbar radiculopathy remains a clinical challenge among primary care clinicians in both assessment and diagnosis. This often leads to misdiagnosis and inappropriate treatment of patients resulting in poor health outcomes, exacerbating this already debilitating condition. This review evaluated 12 primary diagnostic accuracy studies that specifically assessed the performance of various individual and grouped clinical neurological tests in detecting nerve root impingement, as established in the current literature. Eight electronic data bases were searched for relevant articles from inception until July 2016. All primary diagnostic studies which investigated the accuracy of clinical neurological test (s) in diagnosing lumbar radiculopathy among patients with low back and referred leg symptoms were screened for inclusion. Qualifying studies were retrieved and independently assessed for methodological quality using the 'Quality Assessment of Diagnostic tests Accuracy Studies' criteria. A total of 12 studies which investigated standard components of clinical neurological examination of (sensory, motor, tendon reflex and neuro-dynamics) of the lumbo-sacral spine were included. The mean inter-observer agreement on quality assessment by two independent reviewers was fair (k = 0.3 - 0.7). The diagnostic performance of sensory testing using MR imaging as a reference standard demonstrated a sensitivity (confidence interval 95%) 0.61 (0.47-0.73) and a specificity of 0.63 (0.38-0.84). Motor tests sensitivity was poor to moderate, ranging from 0.13 (0.04-0.31) to 0.61 (0.36-0.83). Generally, the diagnostic performance of reflex testing was notably good with specificity ranging from (confidence interval 95%) 0.60 (0.51-0.69) to 0.93 (0.87-0.97) and sensitivity ranging from 0.14 (0.09-0.21) to 0.67 (0.21-0.94). Femoral nerve stretch test had a high sensitivity of (confidence interval 95%) 1.00 (0.40-1.00) and specificity of 0.83 (0.52-0.98) while SLR test recorded a mean sensitivity of 0.84 (0.72-0.92) and specificity of 0.78 (0.67-0.87). There is a scarcity of studies on the diagnostic accuracy of clinical neurological examination testing. Furthermore there seem to be a disconnect among researchers regarding the diagnostic utility of lower limb neuro-dynamic tests which include the Straight Leg Raise and Femoral Nerve tests for sciatic and femoral nerve respectively. Whether these tests are able to detect the presence of disc herniation and subsequent nerve root compression or hyper-sensitivity of the sacral and femoral plexus due to mechanical irritation still remains debatable.

Off-line simulation inspires insight: A neurodynamics approach to efficient robot task learning.

PubMed

Sousa, Emanuel; Erlhagen, Wolfram; Ferreira, Flora; Bicho, Estela

2015-12-01

There is currently an increasing demand for robots able to acquire the sequential organization of tasks from social learning interactions with ordinary people. Interactive learning-by-demonstration and communication is a promising research topic in current robotics research. However, the efficient acquisition of generalized task representations that allow the robot to adapt to different users and contexts is a major challenge. In this paper, we present a dynamic neural field (DNF) model that is inspired by the hypothesis that the nervous system uses the off-line re-activation of initial memory traces to incrementally incorporate new information into structured knowledge. To achieve this, the model combines fast activation-based learning to robustly represent sequential information from single task demonstrations with slower, weight-based learning during internal simulations to establish longer-term associations between neural populations representing individual subtasks. The efficiency of the learning process is tested in an assembly paradigm in which the humanoid robot ARoS learns to construct a toy vehicle from its parts. User demonstrations with different serial orders together with the correction of initial prediction errors allow the robot to acquire generalized task knowledge about possible serial orders and the longer term dependencies between subgoals in very few social learning interactions. This success is shown in a joint action scenario in which ARoS uses the newly acquired assembly plan to construct the toy together with a human partner. Copyright © 2015 Elsevier Ltd. All rights reserved.

Linking online gaming and addictive behavior: converging evidence for a general reward deficiency in frequent online gamers.

PubMed

Hahn, Tim; Notebaert, Karolien Hilde; Dresler, Thomas; Kowarsch, Linda; Reif, Andreas; Fallgatter, Andreas J

2014-01-01

Millions of people regularly play so-called massively multiplayer online role playing games (MMORPGs). Recently, it has been argued that MMORPG overuse is becoming a significant health problem worldwide. Symptoms such as tolerance, withdrawal, and craving have been described. Based on behavioral, resting state, and task-related neuroimaging data, we test whether frequent players of the MMORPG "World of Warcraft" (WoW) - similar to drug addicts and individuals with an increased risk for addictions - show a generally deficient reward system. In frequent players of the MMORPG "World of Warcraft" (WoW-players) and in a control group of non-gamers we assessed (1) trait sensitivity to reward (SR), (2) BOLD responses during monetary reward processing in the ventral striatum, and (3) ventral-striatal resting-state dynamics. We found a decreased neural activation in the ventral striatum during the anticipation of both small and large monetary rewards. Additionally, we show generally altered neurodynamics in this region independent of any specific task for WoW players (resting state). On the behavioral level, we found differences in trait SR, suggesting that the reward processing deficiencies found in this study are not a consequence of gaming, but predisposed to it. These findings empirically support a direct link between frequent online gaming and the broad field of behavioral and drug addiction research, thus opening new avenues for clinical interventions in addicted gamers and potentially improving the assessment of addiction-risk in the vast population of frequent gamers.

Applying the Neurodynamics of Emotional Circular Causalities in Psychosocial and Cognitive Therapy using Multi-Sensory Environments: An ORBDE Case Study Analysis.

PubMed

Ryan, Janice

2017-10-01

This exploratory, evidence-based practice research study focuses on presenting a plausible mesoscopic brain dynamics hypothesis for the benefits of treating clients with psychosocial and cognitive challenges using a mindful therapeutic approach and multi-sensory environments. After an extensive neuroscientific review of the therapeutic benefits of mindfulness, a multi-sensory environment is presented as a window of therapeutic opportunity to more quickly and efficiently facilitate the neurobiological experience of becoming more mindful or conscious of self and environment. The complementary relationship between the default mode network and the executive attention network is offered as a neurobiological hypothesis that could explain positive occupational engagement pattern shifts in a case study video of a hospice client with advanced dementia during multi-sensory environment treatment. Orbital Decomposition is used for a video analysis that shows a significant behavioral pattern shift consistent with dampening of the perceptual system attractors that contribute to negative emotional circular causalities in a variety of client populations. This treatment approach may also prove to be valuable for any person who has developed circular causalities due to feelings of isolation, victimization, or abuse. A case is made for broader applications of this intervention that may positively influence perception during the information transfer and processing of hippocampal learning. Future research is called for to determine if positive affective, interpersonal, and occupational engagement pattern shifts during treatment are related to the improved default mode network-executive attention network synchrony characteristic of increased mindfulness.

Refinement of learned skilled movement representation in motor cortex deep output layer

PubMed Central

Li, Qian; Ko, Ho; Qian, Zhong-Ming; Yan, Leo Y. C.; Chan, Danny C. W.; Arbuthnott, Gordon; Ke, Ya; Yung, Wing-Ho

2017-01-01

The mechanisms underlying the emergence of learned motor skill representation in primary motor cortex (M1) are not well understood. Specifically, how motor representation in the deep output layer 5b (L5b) is shaped by motor learning remains virtually unknown. In rats undergoing motor skill training, we detect a subpopulation of task-recruited L5b neurons that not only become more movement-encoding, but their activities are also more structured and temporally aligned to motor execution with a timescale of refinement in tens-of-milliseconds. Field potentials evoked at L5b in vivo exhibit persistent long-term potentiation (LTP) that parallels motor performance. Intracortical dopamine denervation impairs motor learning, and disrupts the LTP profile as well as the emergent neurodynamical properties of task-recruited L5b neurons. Thus, dopamine-dependent recruitment of L5b neuronal ensembles via synaptic reorganization may allow the motor cortex to generate more temporally structured, movement-encoding output signal from M1 to downstream circuitry that drives increased uniformity and precision of movement during motor learning. PMID:28598433

[Neuropsychological evaluation of children in low conciseness state after a severe traumatic brain injury].

PubMed

Fufaeva, E V; Mikadze, Yu V; Lukyanov, V I

2017-01-01

To follow up patterns of cognitive recovery in children (6-17 years of age) at the first four months after a severe traumatic brain injury (TBI). Seventeen children with TBI (GCS ≤8) were evaluated with the Coma Recovery Scale-R (CRS). Children were stratified into three groups according to their consciousness recovery. Seven children regained their consciousness completely and were assessed by the Luria Neuropsychological Battery test. Six children remained in the minimally conscious state (MCS) and were tested by the adapted procedure of neuropsychological assessment during the first four months. Four children with low level of consciousness were evaluated with CRS. The most destroying functions at the early recovery period were the processing speed (neurodynamics of mental activity), executive functions and memory. Children with the anterior cortex damage had the slowest dynamics of recovery. The slower dynamics of consciousness recovery was combined with severe primary damages of visual gnosis, speech and executive functions according to neuropsychological examination. The positive dynamics of consciousness recovery was combined with early behavioral changes and the greater rate of behavioral changes.

Neural manual vs. robotic assisted mobilization to improve motion and reduce pain hypersensitivity in hand osteoarthritis: study protocol for a randomized controlled trial.

PubMed

Villafañe, Jorge Hugo; Valdes, Kristin; Imperio, Grace; Borboni, Alberto; Cantero-Téllez, Raquel; Galeri, Silvia; Negrini, Stefano

2017-05-01

[Purpose] The aim of the present study is to detail the protocol for a randomised controlled trial (RCT) of neural manual vs. robotic assisted on pain in sensitivity as well as analyse the quantitative and qualitative movement of hand in subjects with hand osteoarthritis. [Subjects and Methods] Seventy-two patients, aged 50 to 90 years old of both genders, with a diagnosis of hand Osteoarthritis (OA), will be recruited. Two groups of 36 participants will receive an experimental intervention (neurodynamic mobilization intervention plus exercise) or a control intervention (robotic assisted passive mobilization plus exercise) for 12 sessions over 4 weeks. Assessment points will be at baseline, end of therapy, and 1 and 3 months after end of therapy. The outcomes of this intervention will be pain and determine the central pain processing mechanisms. [Result] Not applicable. [Conclusion] If there is a reduction in pain hypersensitivity in hand OA patients it can suggest that supraspinal pain-inhibitory areas, including the periaqueductal gray matter, can be stimulated by joint mobilization.

Breathing as a Fundamental Rhythm of Brain Function.

PubMed

Heck, Detlef H; McAfee, Samuel S; Liu, Yu; Babajani-Feremi, Abbas; Rezaie, Roozbeh; Freeman, Walter J; Wheless, James W; Papanicolaou, Andrew C; Ruszinkó, Miklós; Sokolov, Yury; Kozma, Robert

2016-01-01

Ongoing fluctuations of neuronal activity have long been considered intrinsic noise that introduces unavoidable and unwanted variability into neuronal processing, which the brain eliminates by averaging across population activity (Georgopoulos et al., 1986; Lee et al., 1988; Shadlen and Newsome, 1994; Maynard et al., 1999). It is now understood, that the seemingly random fluctuations of cortical activity form highly structured patterns, including oscillations at various frequencies, that modulate evoked neuronal responses (Arieli et al., 1996; Poulet and Petersen, 2008; He, 2013) and affect sensory perception (Linkenkaer-Hansen et al., 2004; Boly et al., 2007; Sadaghiani et al., 2009; Vinnik et al., 2012; Palva et al., 2013). Ongoing cortical activity is driven by proprioceptive and interoceptive inputs. In addition, it is partially intrinsically generated in which case it may be related to mental processes (Fox and Raichle, 2007; Deco et al., 2011). Here we argue that respiration, via multiple sensory pathways, contributes a rhythmic component to the ongoing cortical activity. We suggest that this rhythmic activity modulates the temporal organization of cortical neurodynamics, thereby linking higher cortical functions to the process of breathing.

Linking Online Gaming and Addictive Behavior: Converging Evidence for a General Reward Deficiency in Frequent Online Gamers

PubMed Central

Hahn, Tim; Notebaert, Karolien Hilde; Dresler, Thomas; Kowarsch, Linda; Reif, Andreas; Fallgatter, Andreas J.

2014-01-01

Millions of people regularly play so-called massively multiplayer online role playing games (MMORPGs). Recently, it has been argued that MMORPG overuse is becoming a significant health problem worldwide. Symptoms such as tolerance, withdrawal, and craving have been described. Based on behavioral, resting state, and task-related neuroimaging data, we test whether frequent players of the MMORPG “World of Warcraft” (WoW) – similar to drug addicts and individuals with an increased risk for addictions – show a generally deficient reward system. In frequent players of the MMORPG “World of Warcraft” (WoW-players) and in a control group of non-gamers we assessed (1) trait sensitivity to reward (SR), (2) BOLD responses during monetary reward processing in the ventral striatum, and (3) ventral-striatal resting-state dynamics. We found a decreased neural activation in the ventral striatum during the anticipation of both small and large monetary rewards. Additionally, we show generally altered neurodynamics in this region independent of any specific task for WoW players (resting state). On the behavioral level, we found differences in trait SR, suggesting that the reward processing deficiencies found in this study are not a consequence of gaming, but predisposed to it. These findings empirically support a direct link between frequent online gaming and the broad field of behavioral and drug addiction research, thus opening new avenues for clinical interventions in addicted gamers and potentially improving the assessment of addiction-risk in the vast population of frequent gamers. PMID:25426039

The situated HKB model: how sensorimotor spatial coupling can alter oscillatory brain dynamics

PubMed Central

Aguilera, Miguel; Bedia, Manuel G.; Santos, Bruno A.; Barandiaran, Xabier E.

2013-01-01

Despite the increase of both dynamic and embodied/situated approaches in cognitive science, there is still little research on how coordination dynamics under a closed sensorimotor loop might induce qualitatively different patterns of neural oscillations compared to those found in isolated systems. We take as a departure point the Haken-Kelso-Bunz (HKB) model, a generic model for dynamic coordination between two oscillatory components, which has proven useful for a vast range of applications in cognitive science and whose dynamical properties are well understood. In order to explore the properties of this model under closed sensorimotor conditions we present what we call the situated HKB model: a robotic model that performs a gradient climbing task and whose “brain” is modeled by the HKB equation. We solve the differential equations that define the agent-environment coupling for increasing values of the agent's sensitivity (sensor gain), finding different behavioral strategies. These results are compared with two different models: a decoupled HKB with no sensory input and a passively-coupled HKB that is also decoupled but receives a structured input generated by a situated agent. We can precisely quantify and qualitatively describe how the properties of the system, when studied in coupled conditions, radically change in a manner that cannot be deduced from the decoupled HKB models alone. We also present the notion of neurodynamic signature as the dynamic pattern that correlates with a specific behavior and we show how only a situated agent can display this signature compared to an agent that simply receives the exact same sensory input. To our knowledge, this is the first analytical solution of the HKB equation in a sensorimotor loop and qualitative and quantitative analytic comparison of spatially coupled vs. decoupled oscillatory controllers. Finally, we discuss the limitations and possible generalization of our model to contemporary neuroscience and philosophy of mind. PMID:23986692

[The neurodynamic core of consciousness and neural Darwinism].

PubMed

Ibáñez, A

In the last decades, the scientific study of consciousness in the scope of the cognitive neurosciences can be considered one of the greatest challenges of contemporary science. The Gerald Edelman theory of consciousness is one of the most promising and controversial perspectives. This theory stands out by its approach to topics usually rejected by other neurophysiologic theories of consciousness, as the case of the neurophysiologic explanation of qualia. The goal of this paper is to review the dynamic core theory of consciousness, presenting the main features of the theory, analyzing the explanation strategies, their empirical extensions, and elaborating some critical considerations about the possibility of the neuroscientific study of qualia. The central and additional theoretical components are analyzed, emphasizing its ontological, restrictive and explanatory assumptions. The properties of conscious phenomena and their cerebral correlates as advanced by the theory are described, and finally its experiments and empirical extensions are examined. The explanatory strategies of the theory are analyzed, based on conceptual isomorphism between the phenomenological properties and the neurophysiological and mathematical measures. Some criticisms could be raised about the limitations of the dynamic core theory, especially regarding its account of the so-called 'hard problem' of consciousness or qualia.

Christfried Jakob's late views (1930-1949) on the psychogenetic function of the cerebral cortex and its localization: culmination of the neurophilosophical thought of a keen brain observer.

PubMed

Théodoridou, Zoë D; Triarhou, Lazaros C

2012-04-01

This article follows the culmination of the scientific thought of the neurobiologist Christfried Jakob (1866-1956) during the later part of his career, based on publications from 1930 to 1949, when he was between 64 and 83 years of age. Jakob emphasized the necessity of bridging philosophy to the biological sciences, neurobiology in particular. Thus, we consider him as one of the early protagonists in the emergence of neurophilosophy in the 20th century. The topics that occupied his mind were the foundations for a future philosophy of the brain, and the 'neurobiogenetic', 'neurodynamic', and 'neuropsychogenetic' problems in relation to how consciousness emerges. Jakob's views have many elements in common with great thinkers of philosophy and psychology, including Immanuel Kant, William James, Edmund Husserl, Henri Bergson, Jean Piaget and Willard Quine. A common denominator can also be discerned between Jakob's dynamic approach and certain aspects of cybernetics and neurophenomenology. Jakob propounded the interdisciplinarity of sciences as an indispensable tool for ultimately solving the enigma of consciousness. Copyright © 2011 Elsevier Inc. All rights reserved.

Neuronal avalanches, epileptic quakes and other transient forms of neurodynamics.

PubMed

Milton, John G

2012-07-01

Power-law behaviors in brain activity in healthy animals, in the form of neuronal avalanches, potentially benefit the computational activities of the brain, including information storage, transmission and processing. In contrast, power-law behaviors associated with seizures, in the form of epileptic quakes, potentially interfere with the brain's computational activities. This review draws attention to the potential roles played by homeostatic mechanisms and multistable time-delayed recurrent inhibitory loops in the generation of power-law phenomena. Moreover, it is suggested that distinctions between health and disease are scale-dependent. In other words, what is abnormal and defines disease it is not the propagation of neural activity but the propagation of activity in a neural population that is large enough to interfere with the normal activities of the brain. From this point of view, epilepsy is a disease that results from a failure of mechanisms, possibly located in part in the cortex itself or in the deep brain nuclei and brainstem, which truncate or otherwise confine the spatiotemporal scales of these power-law phenomena. © 2012 The Author. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Nonlinear analysis of EEGs of patients with major depression during different emotional states.

PubMed

Akdemir Akar, Saime; Kara, Sadık; Agambayev, Sümeyra; Bilgiç, Vedat

2015-12-01

Although patients with major depressive disorder (MDD) have dysfunctions in cognitive behaviors and the regulation of emotions, the underlying brain dynamics of the pathophysiology are unclear. Therefore, nonlinear techniques can be used to understand the dynamic behavior of the EEG signals of MDD patients. To investigate and clarify the dynamics of MDD patients׳ brains during different emotional states, EEG recordings were analyzed using nonlinear techniques. The purpose of the present study was to assess whether there are different EEG complexities that discriminate between MDD patients and healthy controls during emotional processing. Therefore, nonlinear parameters, such as Katz fractal dimension (KFD), Higuchi fractal dimension (HFD), Shannon entropy (ShEn), Lempel-Ziv complexity (LZC) and Kolmogorov complexity (KC), were computed from the EEG signals of two groups under different experimental states: noise (negative emotional content) and music (positive emotional content) periods. First, higher complexity values were generated by MDD patients relative to controls. Significant differences were obtained in the frontal and parietal scalp locations using KFD (p<0.001), HFD (p<0.05), and LZC (p=0.05). Second, lower complexities were observed only in the controls when they were subjected to music compared to the resting baseline state in the frontal (p<0.05) and parietal (p=0.005) regions. In contrast, the LZC and KFD values of patients increased in the music period compared to the resting state in the frontal region (p<0.05). Third, the patients׳ brains had higher complexities when they were exposed to noise stimulus than did the controls׳ brains. Moreover, MDD patients׳ negative emotional bias was demonstrated by their higher brain complexities during the noise period than the music stimulus. Additionally, we found that the KFD, HFD and LZC values were more sensitive in discriminating between patients and controls than the ShEn and KC measures, according to the results of ANOVA and ROC calculations. It can be concluded that the nonlinear analysis may be a useful and discriminative tool in investigating the neuro-dynamic properties of the brain in patients with MDD during emotional stimulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spatiotemporal neurodynamics of automatic temporal expectancy in 9-month old infants.

PubMed

Mento, Giovanni; Valenza, Eloisa

2016-11-04

Anticipating events occurrence (Temporal Expectancy) is a crucial capacity for survival. Yet, there is little evidence about the presence of cortical anticipatory activity from infancy. In this study we recorded the High-density electrophysiological activity in 9 month-old infants and adults undergoing an audio-visual S1-S2 paradigm simulating a lifelike "Peekaboo" game inducing automatic temporal expectancy of smiling faces. The results indicate in the S2-preceding Contingent Negative Variation (CNV) an early electrophysiological signature of expectancy-based anticipatory cortical activity. Moreover, the progressive CNV amplitude increasing across the task suggested that implicit temporal rule learning is at the basis of expectancy building-up over time. Cortical source reconstruction suggested a common CNV generator between adults and infants in the right prefrontal cortex. The decrease in the activity of this area across the task (time-on-task effect) further implied an early, core role of this region in implicit temporal rule learning. By contrast, a time-on-task activity boost was found in the supplementary motor area (SMA) in adults and in the temporoparietal regions in infants. Altogether, our findings suggest that the capacity of the human brain to translate temporal predictions into anticipatory neural activity emerges ontogenetically early, although the underlying spatiotemporal cortical dynamics change across development.

Medical diagnosis of cubital tunnel syndrome ameliorated with thrust manipulation of the elbow and carpals

PubMed Central

Kearns, Gary; Wang, Sharon

2012-01-01

This case report describes the effectiveness of thrust manipulation to the elbow and carpals in the management of a patient referred with a medical diagnosis of cubital tunnel syndrome (CuTS). The patient was a 45-year-old woman with a 6-week history of right medial elbow pain, ulnar wrist pain, and intermittent paresthesia in the ulnar nerve distribution. Upon initial assessment, she presented with a positive elbow flexion test and upper limb neurodynamic test with ulnar nerve bias. A biomechanical assessment of the elbow and carpals revealed a loss of lateral glide of the humerus on the ulna and a loss of palmar glide of the triquetral on the hamate. After the patient received two thrust manipulations of the elbow and one thrust manipulation of the carpals over the course of four sessions, her pain and paresthesia were resolved. This case demonstrates that the use of thrust manipulation to the elbow and carpals may be an effective approach in the management of insidious onset CuTS. This patient was successfully treated with thrust manipulation when joint dysfunction of the elbow and wrist were appropriately identified. This case report may shed light on the examination and management of insidious onset CuTS. PMID:23633888

Population density equations for stochastic processes with memory kernels

NASA Astrophysics Data System (ADS)

Lai, Yi Ming; de Kamps, Marc

2017-06-01

We present a method for solving population density equations (PDEs)-a mean-field technique describing homogeneous populations of uncoupled neurons—where the populations can be subject to non-Markov noise for arbitrary distributions of jump sizes. The method combines recent developments in two different disciplines that traditionally have had limited interaction: computational neuroscience and the theory of random networks. The method uses a geometric binning scheme, based on the method of characteristics, to capture the deterministic neurodynamics of the population, separating the deterministic and stochastic process cleanly. We can independently vary the choice of the deterministic model and the model for the stochastic process, leading to a highly modular numerical solution strategy. We demonstrate this by replacing the master equation implicit in many formulations of the PDE formalism by a generalization called the generalized Montroll-Weiss equation—a recent result from random network theory—describing a random walker subject to transitions realized by a non-Markovian process. We demonstrate the method for leaky- and quadratic-integrate and fire neurons subject to spike trains with Poisson and gamma-distributed interspike intervals. We are able to model jump responses for both models accurately to both excitatory and inhibitory input under the assumption that all inputs are generated by one renewal process.

The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs

PubMed Central

Carhart-Harris, Robin L.; Leech, Robert; Hellyer, Peter J.; Shanahan, Murray; Feilding, Amanda; Tagliazucchi, Enzo; Chialvo, Dante R.; Nutt, David

2014-01-01

Entropy is a dimensionless quantity that is used for measuring uncertainty about the state of a system but it can also imply physical qualities, where high entropy is synonymous with high disorder. Entropy is applied here in the context of states of consciousness and their associated neurodynamics, with a particular focus on the psychedelic state. The psychedelic state is considered an exemplar of a primitive or primary state of consciousness that preceded the development of modern, adult, human, normal waking consciousness. Based on neuroimaging data with psilocybin, a classic psychedelic drug, it is argued that the defining feature of “primary states” is elevated entropy in certain aspects of brain function, such as the repertoire of functional connectivity motifs that form and fragment across time. Indeed, since there is a greater repertoire of connectivity motifs in the psychedelic state than in normal waking consciousness, this implies that primary states may exhibit “criticality,” i.e., the property of being poised at a “critical” point in a transition zone between order and disorder where certain phenomena such as power-law scaling appear. Moreover, if primary states are critical, then this suggests that entropy is suppressed in normal waking consciousness, meaning that the brain operates just below criticality. It is argued that this entropy suppression furnishes normal waking consciousness with a constrained quality and associated metacognitive functions, including reality-testing and self-awareness. It is also proposed that entry into primary states depends on a collapse of the normally highly organized activity within the default-mode network (DMN) and a decoupling between the DMN and the medial temporal lobes (which are normally significantly coupled). These hypotheses can be tested by examining brain activity and associated cognition in other candidate primary states such as rapid eye movement (REM) sleep and early psychosis and comparing these with non-primary states such as normal waking consciousness and the anaesthetized state. PMID:24550805

The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs.

PubMed

Carhart-Harris, Robin L; Leech, Robert; Hellyer, Peter J; Shanahan, Murray; Feilding, Amanda; Tagliazucchi, Enzo; Chialvo, Dante R; Nutt, David

2014-01-01

Entropy is a dimensionless quantity that is used for measuring uncertainty about the state of a system but it can also imply physical qualities, where high entropy is synonymous with high disorder. Entropy is applied here in the context of states of consciousness and their associated neurodynamics, with a particular focus on the psychedelic state. The psychedelic state is considered an exemplar of a primitive or primary state of consciousness that preceded the development of modern, adult, human, normal waking consciousness. Based on neuroimaging data with psilocybin, a classic psychedelic drug, it is argued that the defining feature of "primary states" is elevated entropy in certain aspects of brain function, such as the repertoire of functional connectivity motifs that form and fragment across time. Indeed, since there is a greater repertoire of connectivity motifs in the psychedelic state than in normal waking consciousness, this implies that primary states may exhibit "criticality," i.e., the property of being poised at a "critical" point in a transition zone between order and disorder where certain phenomena such as power-law scaling appear. Moreover, if primary states are critical, then this suggests that entropy is suppressed in normal waking consciousness, meaning that the brain operates just below criticality. It is argued that this entropy suppression furnishes normal waking consciousness with a constrained quality and associated metacognitive functions, including reality-testing and self-awareness. It is also proposed that entry into primary states depends on a collapse of the normally highly organized activity within the default-mode network (DMN) and a decoupling between the DMN and the medial temporal lobes (which are normally significantly coupled). These hypotheses can be tested by examining brain activity and associated cognition in other candidate primary states such as rapid eye movement (REM) sleep and early psychosis and comparing these with non-primary states such as normal waking consciousness and the anaesthetized state.

Cycles of insanity and creativity within contemplative neural systems.

PubMed

Thaler, Stephen L

2016-09-01

Random connection weight disturbances within an assembly of artificial neural networks (ANN) drive a progression of activation patterns that are tantamount to the memories and ideas nucleating within the brain's cortex. The numerical evaluation of these pattern-based notions by another, more placid system of ANNs governs the magnitude of weight disturbances administered to the former assembly, that perturbative intensity in turn controlling the novelty of the resulting ideational stream as well as the retention of newly formed concepts. In search of solution patterns to posed problems, such collaborating neural systems autonomously cycle between two extremes in mean synaptic perturbation level. The higher limit, characterized by chaos and inattentiveness to exogenous input patterns, is the regime in which ideas first form and incubate. The lower bound, marked by relative synaptic tranquility, is favorable to the reactivation and reinforcement of concepts first seeded during heightened perturbation. When considering this synthetic neural architecture as a cognitive model, the proposed source of such synaptic fluctuations is volume neurotransmitter release within cortex where both ideational and critic nets are commingled. As a result of their overlap, not only are the generative cortical networks suffused with neurotransmitters, but also those functioning in a critic role, leading to altered 'opinions' about the perturbation-driven stream of consciousness that then govern the injection of neurotransmitters into cortex. The likely effect of such chemical feedback is that the brain constantly cycles between states of idea generating chaos and perception stabilizing tranquility in much the same way that creative artificial neural systems do. Postulating that ideas are potentially useful or interesting false memories born within such turmoil, creativity appears to take place through a cyclic process consisting of alternating phases of (1) cognitive incapacitation, during which confabulatory notions incubate, and (2) synaptic calm when these incubated thoughts reemerge and reinforce themselves as they are then recognized for their value by a lucid perceptual apparatus. Extremes in such cycling, especially within the former dysfunctional phase, would be problematic from a mental health perspective. Whereas the literature is replete with findings linking creativity and various psychopathologies, the main hypothesis advanced herein is that the neurodynamics of both phenomena are the same. If vindicated, this theory may lead to advanced treatments that could potentially boost creativity as well as safeguard against the associated cognitive and psychological disorders, all through control of just one parameter, the difference between cortical concentrations of excitatory and inhibitory neurotransmitters. Copyright © 2016 Elsevier Ltd. All rights reserved.

Frontal Preparatory Neural Oscillations Associated with Cognitive Control: A Developmental Study Comparing Young Adults and Adolescents

PubMed Central

Hwang, Kai; Ghuman, Avniel S.; Manoach, Dara S.; Jones, Stephanie R.; Luna, Beatriz

2016-01-01

Functional magnetic resonance imaging (fMRI) studies suggest that age-related changes in the frontal cortex may underlie developmental improvements in cognitive control. In the present study we used magnetoencephalography (MEG) to identify frontal oscillatory neurodynamics that support age-related improvements in cognitive control during adolescence. We characterized the differences in neural oscillations in adolescents and adults during the preparation to suppress a prepotent saccade (antisaccade trials – AS) compared to preparing to generate a more automatic saccade (prosaccade trials – PS). We found that for adults, AS were associated with increased beta-band (16–38 Hz) power in the dorsal lateral prefrontal cortex (DLPFC), enhanced alpha- to low beta-band (10–18 Hz) power in the frontal eye field (FEF) that predicted performance, and increased cross-frequency alpha-beta (10–26 Hz) amplitude coupling between the DLPFC and the FEF. Developmental comparisons between adults and adolescents revealed similar engagement of DLPFC beta-band power but weaker FEF alpha-band power, and lower cross-frequency coupling between the DLPFC and the FEF in adolescents. These results suggest that lateral prefrontal neural activity associated with cognitive control is adult-like by adolescence; the development of cognitive control from adolescence to adulthood is instead associated with increases in prefrontal connectivity and strengthening of inhibition signaling for suppressing task-incompatible processes. PMID:27173759

Neurodynamics of executive control processes in bilinguals: evidence from ERP and source reconstruction analyses.

PubMed

Heidlmayr, Karin; Hemforth, Barbara; Moutier, Sylvain; Isel, Frédéric

2015-01-01

The present study was designed to examine the impact of bilingualism on the neuronal activity in different executive control processes namely conflict monitoring, control implementation (i.e., interference suppression and conflict resolution) and overcoming of inhibition. Twenty-two highly proficient but non-balanced successive French-German bilingual adults and 22 monolingual adults performed a combined Stroop/Negative priming task while event-related potential (ERP) were recorded online. The data revealed that the ERP effects were reduced in bilinguals in comparison to monolinguals but only in the Stroop task and limited to the N400 and the sustained fronto-central negative-going potential time windows. This result suggests that bilingualism may impact the process of control implementation rather than the process of conflict monitoring (N200). Critically, our study revealed a differential time course of the involvement of the anterior cingulate cortex (ACC) and the prefrontal cortex (PFC) in conflict processing. While the ACC showed major activation in the early time windows (N200 and N400) but not in the latest time window (late sustained negative-going potential), the PFC became unilaterally active in the left hemisphere in the N400 and the late sustained negative-going potential time windows. Taken together, the present electroencephalography data lend support to a cascading neurophysiological model of executive control processes, in which ACC and PFC may play a determining role.

Neurodynamics of executive control processes in bilinguals: evidence from ERP and source reconstruction analyses

PubMed Central

Heidlmayr, Karin; Hemforth, Barbara; Moutier, Sylvain; Isel, Frédéric

2015-01-01

The present study was designed to examine the impact of bilingualism on the neuronal activity in different executive control processes namely conflict monitoring, control implementation (i.e., interference suppression and conflict resolution) and overcoming of inhibition. Twenty-two highly proficient but non-balanced successive French–German bilingual adults and 22 monolingual adults performed a combined Stroop/Negative priming task while event-related potential (ERP) were recorded online. The data revealed that the ERP effects were reduced in bilinguals in comparison to monolinguals but only in the Stroop task and limited to the N400 and the sustained fronto-central negative-going potential time windows. This result suggests that bilingualism may impact the process of control implementation rather than the process of conflict monitoring (N200). Critically, our study revealed a differential time course of the involvement of the anterior cingulate cortex (ACC) and the prefrontal cortex (PFC) in conflict processing. While the ACC showed major activation in the early time windows (N200 and N400) but not in the latest time window (late sustained negative-going potential), the PFC became unilaterally active in the left hemisphere in the N400 and the late sustained negative-going potential time windows. Taken together, the present electroencephalography data lend support to a cascading neurophysiological model of executive control processes, in which ACC and PFC may play a determining role. PMID:26124740

[Association of cognitive impairments with carbohydrate and lipid metabolic parameters in type 2 diabetes mellitus patients undergoing coronary bypass surgery].

PubMed

Trubnikova, О А; Mamontova, A S; Tarasova, I V; Maleva, O V; Kuzmina, A A; Barbarash, O L

2015-01-01

AIM. To comparatively analyze neuropsychological parameters in patients with coronary artery disease (CAD) depending on the presence of type 2 diabetes mellitus (DM) and to evaluate their relationship to carbohydrate and lipid metabolic parameters. Fifty-two male patients with type 2 DM (mean age 58.0 ± 5.7 years) and 46 male patients without this condition (mean age 57.1 ± 6.2 years) were examined. Besides standard clinical examination, neurophysiological testing and determinations of glycated hemoglobin (HbA(1c),) and insulin concentrations, QUICKI index, and blood lipid profile were made. The patients with DM differed from those without DM in the lower speeds of sensorimotor reactions during neurodynamic testing and in worse attention values. In the patients with type 2 DM, the worse neuropsychological status was associated with the higher plasma concentrations of glucose, insulin, HbA(1c), total cholesterol, low-density lipoproteins, and triglycerides and with the lower levels of high-density lipoproteins. These relationships were not observed in the patients without DM. The patients with CAD concurrent with DM had a worse neurophysiological status than those without DM. Only the DM group demonstrated a relationship between cognitive impairments and carbohydrate metabolic markers. Carbohydrate and lipid metabolic disturbances may be assumed to make a negative contribution to the development of cognitive impairments in patients with CAD concurrent with type 2 DM.

3D+T motion analysis with nanosensors

NASA Astrophysics Data System (ADS)

Leduc, Jean-Pierre

2017-09-01

This paper addresses the problem of motion analysis performed in a signal sampled on an irregular grid spread in 3-dimensional space and time (3D+T). Nanosensors can be randomly scattered in the field to form a "sensor network". Once released, each nanosensor transmits at its own fixed pace information which corresponds to some physical variable measured in the field. Each nanosensor is supposed to have a limited lifetime given by a Poisson-exponential distribution after release. The motion analysis is supported by a model based on a Lie group called the Galilei group that refers to the actual mechanics that takes place on some given geometry. The Galilei group has representations in the Hilbert space of the captured signals. Those representations have the properties to be unitary, irreducible and square-integrable and to enable the existence of admissible continuous wavelets fit for motion analysis. The motion analysis can be considered as a so-called "inverse problem" where the physical model is inferred to estimate the kinematical parameters of interest. The estimation of the kinematical parameters is performed by a gradient algorithm. The gradient algorithm extends in the trajectory determination. Trajectory computation is related to a Lagrangian-Hamiltonian formulation and fits into a neuro-dynamic programming approach that can be implemented in the form of a Q-learning algorithm. Applications relevant for this problem can be found in medical imaging, Earth science, military, and neurophysiology.

Dynamic functional connectivity and individual differences in emotions during social stress.

PubMed

Tobia, Michael J; Hayashi, Koby; Ballard, Grey; Gotlib, Ian H; Waugh, Christian E

2017-12-01

Exposure to acute stress induces multiple emotional responses, each with their own unique temporal dynamics. Dynamic functional connectivity (dFC) measures the temporal variability of network synchrony and captures individual differences in network neurodynamics. This study investigated the relationship between dFC and individual differences in emotions induced by an acute psychosocial stressor. Sixteen healthy adult women underwent fMRI scanning during a social evaluative threat (SET) task, and retrospectively completed questionnaires that assessed individual differences in subjectively experienced positive and negative emotions about stress and stress relief during the task. Group dFC was decomposed with parallel factor analysis (PARAFAC) into 10 components, each with a temporal signature, spatial network of functionally connected regions, and vector of participant loadings that captures individual differences in dFC. Participant loadings of two networks were positively correlated with stress-related emotions, indicating the existence of networks for positive and negative emotions. The emotion-related networks involved the ventromedial prefrontal cortex, cingulate cortex, anterior insula, and amygdala, among other distributed brain regions, and time signatures for these emotion-related networks were uncorrelated. These findings demonstrate that individual differences in stress-induced positive and negative emotions are each uniquely associated with large-scale brain networks, and suggest that dFC is a mechanism that generates individual differences in the emotional components of the stress response. Hum Brain Mapp 38:6185-6205, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A cortical network model of cognitive and emotional influences in human decision making.

PubMed

Nazir, Azadeh Hassannejad; Liljenström, Hans

2015-10-01

Decision making (DM)(2) is a complex process that appears to involve several brain structures. In particular, amygdala, orbitofrontal cortex (OFC) and lateral prefrontal cortex (LPFC) seem to be essential in human decision making, where both emotional and cognitive aspects are taken into account. In this paper, we present a computational network model representing the neural information processing of DM, from perception to behavior. We model the population dynamics of the three neural structures (amygdala, OFC and LPFC), as well as their interaction. In our model, the neurodynamic activity of amygdala and OFC represents the neural correlates of secondary emotion, while the activity of certain neural populations in OFC alone represents the outcome expectancy of different options. The cognitive/rational aspect of DM is associated with LPFC. Our model is intended to give insights on the emotional and cognitive processes involved in DM under various internal and external contexts. Different options for actions are represented by the oscillatory activity of cell assemblies, which may change due to experience and learning. Knowledge and experience of the outcome of our decisions and actions can eventually result in changes in our neural structures, attitudes and behaviors. Simulation results may have implications for how we make decisions for our individual actions, as well as for societal choices, where we take examples from transport and its impact on CO2 emissions and climate change. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Estimating direction in brain-behavior interactions: Proactive and reactive brain states in driving.

PubMed

Garcia, Javier O; Brooks, Justin; Kerick, Scott; Johnson, Tony; Mullen, Tim R; Vettel, Jean M

2017-04-15

Conventional neuroimaging analyses have ascribed function to particular brain regions, exploiting the power of the subtraction technique in fMRI and event-related potential analyses in EEG. Moving beyond this convention, many researchers have begun exploring network-based neurodynamics and coordination between brain regions as a function of behavioral parameters or environmental statistics; however, most approaches average evoked activity across the experimental session to study task-dependent networks. Here, we examined on-going oscillatory activity as measured with EEG and use a methodology to estimate directionality in brain-behavior interactions. After source reconstruction, activity within specific frequency bands (delta: 2-3Hz; theta: 4-7Hz; alpha: 8-12Hz; beta: 13-25Hz) in a priori regions of interest was linked to continuous behavioral measurements, and we used a predictive filtering scheme to estimate the asymmetry between brain-to-behavior and behavior-to-brain prediction using a variant of Granger causality. We applied this approach to a simulated driving task and examined directed relationships between brain activity and continuous driving performance (steering behavior or vehicle heading error). Our results indicated that two neuro-behavioral states may be explored with this methodology: a Proactive brain state that actively plans the response to the sensory information and is characterized by delta-beta activity, and a Reactive brain state that processes incoming information and reacts to environmental statistics primarily within the alpha band. Published by Elsevier Inc.

Neurodynamics of an election.

PubMed

da Rocha, Armando Freitas; Rocha, Fábio Theoto; Burattini, Marcelo Nascimento; Massad, Eduardo

2010-09-10

Variables influencing decision-making in real settings, as in the case of voting decisions, are uncontrollable and in many times even unknown to the experimenter. In this case, the experimenter has to study the intention to decide (vote) as close as possible in time to the moment of the real decision (election day). Here, we investigated the brain activity associated with the voting intention declared 1 week before the election day of the Brazilian Firearms Control Referendum about prohibiting the commerce of firearms. Two alliances arose in the Congress to run the campaigns for YES (for the prohibition of firearm commerce) and NO (against the prohibition of firearm commerce) voting. Time constraints imposed by the necessity of studying a reasonable number (here, 32) of voters during a very short time (5 days) made the EEG the tool of choice for recording the brain activity associated with voting decision. Recent fMRI and EEG studies have shown decision-making as a process due to the enrollment of defined neuronal networks. In this work, a special EEG technique is applied to study the topology of the voting decision-making networks and is compared to the results of standard ERP procedures. The results show that voting decision-making enrolled networks in charge of calculating the benefits and risks of the decision of prohibiting or allowing firearm commerce and that the topology of such networks was vote- (i.e., YES/NO-) sensitive. 2010 Elsevier B.V. All rights reserved.

The Parkinsonian Subthalamic Network: Measures of Power, Linear, and Non-linear Synchronization and their Relationship to L-DOPA Treatment and OFF State Motor Severity.

PubMed

West, Timothy; Farmer, Simon; Berthouze, Luc; Jha, Ashwani; Beudel, Martijn; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Brown, Peter; Litvak, Vladimir

2016-01-01

In this paper we investigated the dopaminergic modulation of neuronal interactions occurring in the subthalamic nucleus (STN) during Parkinson's disease (PD). We utilized linear measures of local and long range synchrony such as power and coherence, as well as Detrended Fluctuation Analysis for Phase Synchrony (DFA-PS)- a recently developed non-linear method that computes the extent of long tailed autocorrelations present in the phase interactions between two coupled signals. Through analysis of local field potentials (LFPs) taken from the STN we seek to determine changes in the neurodynamics that may underpin the pathophysiology of PD in a group of 12 patients who had undergone surgery for deep brain stimulation. We demonstrate up modulation of alpha-theta (5-12 Hz) band power in response to L-DOPA treatment, whilst low beta band power (15-20 Hz) band-power is suppressed. We also find evidence for significant local connectivity within the region surrounding STN although there was evidence for its modulation via administration of L-DOPA. Further to this we present evidence for a positive correlation between the phase ordering of bilateral STN interactions and the severity of bradykinetic and rigidity symptoms in PD. Although, the ability of non-linear measures to predict clinical state did not exceed standard measures such as beta power, these measures may help identify the connections which play a role in pathological dynamics.

Multimodal physiotherapy treatment based on a biobehavioral approach for patients with chronic cervico-craniofacial pain: a prospective case series.

PubMed

Marcos-Martín, Fernando; González-Ferrero, Luis; Martín-Alcocer, Noelia; Paris-Alemany, Alba; La Touche, Roy

2018-01-17

The purpose of this prospective case series was to observe and describe changes in patients with chronic cervico-craniofacial pain of muscular origin treated with multimodal physiotherapy based on a biobehavioral approach. Nine patients diagnosed with chronic myofascial temporomandibular disorder and neck pain were treated with 6 sessions over the course of 2 weeks including: (1) orthopedic manual physiotherapy (joint mobilizations, neurodynamic mobilization, and dynamic soft tissue mobilizations); (2) therapeutic exercises (motor control and muscular endurance exercises); and (3) patient education. The outcome measures of craniofacial (CF-PDI) and neck disability (NDI), kinesiophobia (TSK-11) and catastrophizing (PCS), and range of cervical and mandibular motion (ROM) and posture were collected at baseline, and at 2 and 14 weeks post-baseline. Compared to baseline, statistically significant (p < 0.01) and clinically meaningful improvements that surpassed the minimal detectable change were observed at 14 weeks in CF-PDI (mean change, 8.11 points; 95% confidence interval (CI): 2.55 to 13.69; d = 1.38), in NDI (mean change, 5 cm; 95% CI: 1.74-8.25; d = 0.98), and in the TSK-11 (mean change, 6.55 cm; 95% CI: 2.79-10.32; d = 1.44). Clinically meaningful improvements in self-reported disability, psychological factors, ROM, and craniocervical posture were observed following a multimodal physiotherapy treatment based on a biobehavioral approach.

THE DYNAMICS OF A NEUROMUSCULAR SYSTEM FUNCTIONAL CONDITION DURING THE PREPARATION FOR IMPORTANT CONTESTS

PubMed Central

Titov, G.

1973-01-01

The aim of this research was to determine a conjugation of the functional condition dynamics of the neuromuscular organs, visual analyser, latent period of the motorial activity and supporting kinosthetic functions at different stages of preparation of the sportsmen for important contests. The following research methods were used to achieve this aim: a functional mobility of the neuromuscular organs was determined with the help of an electrostimulation method (excitability thresholds, frequency range of optimum and maximum rhythm, data on the changes of a bioelectric potential in relation to electrical stimuli); a functional condition of the visual analyser was determined with the use of an electrostimulation method (excitability thresholds, frequency range of phosefan in the reaction to a threshold irritant); a grey matter neurodynamics was determined with the help of a chronoreflexometry using an audio irritant of a different power with the preliminary strain of motor centres or without it; supporting kinosthetic functions were determined with the help of seismotremography and stabilography (frequency and amplitude of tremor, deviations of the gravity centre of the body in different positions of the Romberg test). All the research on the systems mentioned was carried out within the preparatory, main and contest periods during the preparation for the important contests. Gymnasts, boxers and fencers were under observation. In all there were carried out 570 observations of 54 sportsmen of a high sporting qualification. The functional condition of the visual analyser at a satisfactory level of training was characterised by relatively low excitability thresholds and high frequency limits of phosefan. The functional mobility of the neuromuscular organs was reduced during this period. The supporting kinosthetic functions became apparent in the instability of frequency and amplitude tremor characteristics and general gravity centre deviations. The latent period of the motor movement reaction was the longest without the preliminary strain of the motor centres. The performance of intense training efforts was accompanied by distinct symptoms of the nervous system excitement against a background of the reduced functional mobility of the neuromuscular organs. Just before the main contests, when the sportsmen were in good training condition, the excitability thresholds of the visual analyser were slightly increasing; frequency limits of phosefan were falling; functional mobility of the neuromuscular organs achieved the highest value; supporting kinosthetic functions were characterised by stable values of the tremor frequency and amplitude and of the deviations of the general gravity centre of the body; minimum latent period of the motor movement reaction was dependent upon the preliminary strain of the motor centres. The data obtained gave us the opportunity to assume that the functional condition dynamics of the systems under consideration might characterise the level of an operative rest, as A. A. Ukhtomsky saw it, as a combatant readiness for physical activity.

Autism, Attention, and Alpha Oscillations: An Electrophysiological Study of Attentional Capture.

PubMed

Keehn, Brandon; Westerfield, Marissa; Müller, Ralph-Axel; Townsend, Jeanne

2017-09-01

Autism spectrum disorder (ASD) is associated with deficits in adaptively orienting attention to behaviorally-relevant information. Neural oscillatory activity plays a key role in brain function and provides a high-resolution temporal marker of attention dynamics. Alpha band (8-12 Hz) activity is associated with both selecting task-relevant stimuli and filtering task-irrelevant information. The present study used electroencephalography (EEG) to examine alpha-band oscillatory activity associated with attentional capture in nineteen children with ASD and twenty-one age- and IQ-matched typically developing (TD) children. Participants completed a rapid serial visual presentation paradigm designed to investigate responses to behaviorally-relevant targets and contingent attention capture by task-irrelevant distractors, which either did or did not share a behaviorally-relevant feature. Participants also completed six minutes of eyes-open resting EEG. In contrast to their TD peers, children with ASD did not evidence posterior alpha desynchronization to behaviorally-relevant targets. Additionally, reduced target-related desynchronization and poorer target detection were associated with increased ASD symptomatology. TD children also showed behavioral and electrophysiological evidence of contingent attention capture, whereas children with ASD showed no behavioral facilitation or alpha desynchronization to distractors that shared a task-relevant feature. Lastly, children with ASD had significantly decreased resting alpha power, and for all participants increased resting alpha levels were associated with greater task-related alpha desynchronization. These results suggest that in ASD under-responsivity and impairments in orienting to salient events within their environment are reflected by atypical EEG oscillatory neurodynamics, which may signify atypical arousal levels and/or an excitatory/inhibitory imbalance.

Classification of epileptic seizures using wavelet packet log energy and norm entropies with recurrent Elman neural network classifier.

PubMed

Raghu, S; Sriraam, N; Kumar, G Pradeep

2017-02-01

Electroencephalogram shortly termed as EEG is considered as the fundamental segment for the assessment of the neural activities in the brain. In cognitive neuroscience domain, EEG-based assessment method is found to be superior due to its non-invasive ability to detect deep brain structure while exhibiting superior spatial resolutions. Especially for studying the neurodynamic behavior of epileptic seizures, EEG recordings reflect the neuronal activity of the brain and thus provide required clinical diagnostic information for the neurologist. This specific proposed study makes use of wavelet packet based log and norm entropies with a recurrent Elman neural network (REN) for the automated detection of epileptic seizures. Three conditions, normal, pre-ictal and epileptic EEG recordings were considered for the proposed study. An adaptive Weiner filter was initially applied to remove the power line noise of 50 Hz from raw EEG recordings. Raw EEGs were segmented into 1 s patterns to ensure stationarity of the signal. Then wavelet packet using Haar wavelet with a five level decomposition was introduced and two entropies, log and norm were estimated and were applied to REN classifier to perform binary classification. The non-linear Wilcoxon statistical test was applied to observe the variation in the features under these conditions. The effect of log energy entropy (without wavelets) was also studied. It was found from the simulation results that the wavelet packet log entropy with REN classifier yielded a classification accuracy of 99.70 % for normal-pre-ictal, 99.70 % for normal-epileptic and 99.85 % for pre-ictal-epileptic.

Amphetamine Exerts Dose-Dependent Changes in Prefrontal Cortex Attractor Dynamics during Working Memory

PubMed Central

Balaguer-Ballester, Emili; Seamans, Jeremy K.; Phillips, Anthony G.; Durstewitz, Daniel

2015-01-01

Modulation of neural activity by monoamine neurotransmitters is thought to play an essential role in shaping computational neurodynamics in the neocortex, especially in prefrontal regions. Computational theories propose that monoamines may exert bidirectional (concentration-dependent) effects on cognition by altering prefrontal cortical attractor dynamics according to an inverted U-shaped function. To date, this hypothesis has not been addressed directly, in part because of the absence of appropriate statistical methods required to assess attractor-like behavior in vivo. The present study used a combination of advanced multivariate statistical, time series analysis, and machine learning methods to assess dynamic changes in network activity from multiple single-unit recordings from the medial prefrontal cortex (mPFC) of rats while the animals performed a foraging task guided by working memory after pretreatment with different doses of d-amphetamine (AMPH), which increases monoamine efflux in the mPFC. A dose-dependent, bidirectional effect of AMPH on neural dynamics in the mPFC was observed. Specifically, a 1.0 mg/kg dose of AMPH accentuated separation between task-epoch-specific population states and convergence toward these states. In contrast, a 3.3 mg/kg dose diminished separation and convergence toward task-epoch-specific population states, which was paralleled by deficits in cognitive performance. These results support the computationally derived hypothesis that moderate increases in monoamine efflux would enhance attractor stability, whereas high frontal monoamine levels would severely diminish it. Furthermore, they are consistent with the proposed inverted U-shaped and concentration-dependent modulation of cortical efficiency by monoamines. PMID:26180194

Specific electrophysiological components disentangle affective sharing and empathic concern in psychopathy.

PubMed

Decety, Jean; Lewis, Kimberly L; Cowell, Jason M

2015-07-01

Empathic impairment is one of the hallmarks of psychopathy, a personality dimension associated with poverty in affective reactions, lack of attachment to others, and a callous disregard for the feelings, rights, and welfare of others. Neuroscience research on the relation between empathy and psychopathy has predominately focused on the affective sharing and cognitive components of empathy in forensic populations, and much less on empathic concern. The current study used high-density electroencephalography in a community sample to examine the spatiotemporal neurodynamic responses when viewing people in physical distress under two subjective contexts: one evoking affective sharing, the other, empathic concern. Results indicate that early automatic (175-275 ms) and later controlled responses (LPP 400-1,000 ms) were differentially modulated by engagement in affective sharing or empathic concern. Importantly, the late event-related potentials (ERP) component was significantly impacted by dispositional empathy and psychopathy, but the early component was not. Individual differences in dispositional empathic concern directly predicted gamma coherence (25-40 Hz), whereas psychopathy was inversely modulatory. Interestingly, significant suppression in the mu/alpha band (8-13 Hz) when perceiving others in distress was positively associated with higher trait psychopathy, which argues against the assumption that sensorimotor resonance underpins empathy. Greater scores on trait psychopathy were inversely related to subjective ratings of both empathic concern and affective sharing. Overall, the study demonstrates that neural markers of affective sharing and empathic concern to the same cues of another's distress can be distinguished at an electrophysiological level, and that psychopathy alters later time-locked differentiations and spectral coherence associated with empathic concern. Copyright © 2015 the American Physiological Society.

Specific electrophysiological components disentangle affective sharing and empathic concern in psychopathy

PubMed Central

Lewis, Kimberly L.; Cowell, Jason M.

2015-01-01

Empathic impairment is one of the hallmarks of psychopathy, a personality dimension associated with poverty in affective reactions, lack of attachment to others, and a callous disregard for the feelings, rights, and welfare of others. Neuroscience research on the relation between empathy and psychopathy has predominately focused on the affective sharing and cognitive components of empathy in forensic populations, and much less on empathic concern. The current study used high-density electroencephalography in a community sample to examine the spatiotemporal neurodynamic responses when viewing people in physical distress under two subjective contexts: one evoking affective sharing, the other, empathic concern. Results indicate that early automatic (175–275 ms) and later controlled responses (LPP 400–1,000 ms) were differentially modulated by engagement in affective sharing or empathic concern. Importantly, the late event-related potentials (ERP) component was significantly impacted by dispositional empathy and psychopathy, but the early component was not. Individual differences in dispositional empathic concern directly predicted gamma coherence (25–40 Hz), whereas psychopathy was inversely modulatory. Interestingly, significant suppression in the mu/alpha band (8–13 Hz) when perceiving others in distress was positively associated with higher trait psychopathy, which argues against the assumption that sensorimotor resonance underpins empathy. Greater scores on trait psychopathy were inversely related to subjective ratings of both empathic concern and affective sharing. Overall, the study demonstrates that neural markers of affective sharing and empathic concern to the same cues of another's distress can be distinguished at an electrophysiological level, and that psychopathy alters later time-locked differentiations and spectral coherence associated with empathic concern. PMID:25948868

Neurodynamics for auditory stream segregation: tracking sounds in the mustached bat's natural environment.

PubMed

Kanwal, Jagmeet S; Medvedev, Andrei V; Micheyl, Christophe

2003-08-01

During navigation and the search phase of foraging, mustached bats emit approximately 25 ms long echolocation pulses (at 10-40 Hz) that contain multiple harmonics of a constant frequency (CF) component followed by a short (3 ms) downward frequency modulation. In the context of auditory stream segregation, therefore, bats may either perceive a coherent pulse-echo sequence (PEPE...), or segregated pulse and echo streams (P-P-P... and E-E-E...). To identify the neural mechanisms for stream segregation in bats, we developed a simple yet realistic neural network model with seven layers and 420 nodes. Our model required recurrent and lateral inhibition to enable output nodes in the network to 'latch-on' to a single tone (corresponding to a CF component in either the pulse or echo), i.e., exhibit differential suppression by the alternating two tones presented at a high rate (> 10 Hz). To test the applicability of our model to echolocation, we obtained neurophysiological data from the primary auditory cortex of awake mustached bats. Event-related potentials reliably reproduced the latching behaviour observed at output nodes in the network. Pulse as well as nontarget (clutter) echo CFs facilitated this latching. Individual single unit responses were erratic, but when summed over several recording sites, they also exhibited reliable latching behaviour even at 40 Hz. On the basis of these findings, we propose that a neural correlate of auditory stream segregation is present within localized synaptic activity in the mustached bat's auditory cortex and this mechanism may enhance the perception of echolocation sounds in the natural environment.

What is the normal response to structural differentiation within the slump and straight leg raise tests?

PubMed

Herrington, Lee; Bendix, Katie; Cornwell, Catherine; Fielden, Nicola; Hankey, Karen

2008-08-01

The purpose of the study was to assess the effect of structural differentiation or sensitising manoeuvres on responses of normal subjects to standard neurodynamic tests of straight leg raise (SLR) and slump test. Eighty-eight (39 males and 49 females) asymptomatic subjects were examined (aged 18-39 mean age 21.9+/-4.1 years). Knee flexion angle was measured using a goniometer during the slump test in two conditions cervical flexion and extension. Hip flexion angle was measured using a goniometer during SLR test in two conditions; ankle dorsi-flexion and neutral. The change in knee flexion, following addition of the structural differentiating manoeuvre to the slump test, was a significant increase in knee flexion angle for both males (change in knee angle; 6.6+/-4.7 degrees /18.7+/-17.5%, p<0.01) and females (change in knee angle 5.4+/-5.8 degrees /17.6+/-23.7%, p<0.01), though showed no difference between sides (p>0.05). During the SLR test, a significant reduction in hip flexion occurred following structural differentiation for both groups (change in hip angle; males = 9.5+/-8.3 degrees /21.5+/-18.8%, p<0.01; females = 15.2+/-9.5 degrees /25.9+/-13.9%, p<0.01), though showed no difference between sides (p>0.05). Structural differentiating manoeuvres have a significant effect on test response in terms of range of movement even in normal asymptomatic individuals. These responses should be taken into account during the assessment clinical reasoning process.

Navy Health Care Executive Competencies

DTIC Science & Technology

2006-04-04

Understanding 10 Information 1 Familiarization with Civilian Health Care and Other Understanding Business 9 Government Systems I Understanding TRICARE 3...Operational Experience/Understanding 10* Acquisitions/Contracting I Understanding Business 9 Automated Health System Information I Understanding TRICARE...Operational Experience/Understanding 10* Acquisitions/Contracting Understanding Business 9 Automated Health System Information Understanding TRICARE 3

EDITORIAL: Why we need a new journal in neural engineering

NASA Astrophysics Data System (ADS)

Durand, Dominique M.

2004-03-01

The field of neural engineering crystallizes for many engineers and scientists an area of research at the interface between neuroscience and engineering. For the last 15 years or so, the discipline of neural engineering (neuroengineering) has slowly appeared at conferences as a theme or track. The first conference devoted entirely to this area was the 1st International IEEE EMBS Conference on Neural Engineering which took place in Capri, Italy in 2003. Understanding how the brain works is considered the ultimate frontier and challenge in science. The complexity of the brain is so great that understanding even the most basic functions will require that we fully exploit all the tools currently at our disposal in science and engineering and simultaneously develop new methods of analysis. While neuroscientists and engineers from varied fields such as brain anatomy, neural development and electrophysiology have made great strides in the analysis of this complex organ, there remains a great deal yet to be uncovered. The potential for applications and remedies deriving from scientific discoveries and breakthroughs is extremely high. As a result of the growing availability of micromachining technology, research into neurotechnology has grown relatively rapidly in recent years and appears to be approaching a critical mass. For example, by understanding how neuronal circuits process and store information, we could design computers with capabilities beyond current limits. By understanding how neurons develop and grow, we could develop new technologies for spinal cord repair or central nervous system repair following neurological disorders. Moreover, discoveries related to higher-level cognitive function and consciousness could have a profound influence on how humans make sense of their surroundings and interact with each other. The ability to successfully interface the brain with external electronics would have enormous implications for our society and facilitate a revolutionary change in the quality of life of persons with sensory and/or motor deficits. Microelectrode technology represents the initial step towards this goal and has already improved the quality of life of many patients, as is evident from the success of auditory prostheses. The cost to society of neurological disorders such as stroke, Parkinson's disease, Alzheimer's disease and epilepsy is staggering. Stroke, which is the third leading cause of death in North America, runs up costs of 40 billion to society per year for its treatment. Costs associated with brain disorders are estimated at 285 billion. Breakthroughs in this field will have a significant impact on the market for enabling technologies. The market for neurological medical devices totaled 2 billion in 1999 and is projected to grow at a rate of 20 to 30% in the next ten years, far outpacing the market for cardiac devices. Although we have all recognized the importance of interdisciplinary research (see the NIH Road map at http://nihroadmap.nih.gov/), the fields of neuroscience and engineering have remained compartmentalized. Collaboration is still difficult since the language of these disciplines is different. Moreover, the scientific journals in these fields are also clearly separate. Researchers involved in neural engineering have a choice of publishing their research in either neuroscience-oriented journals such as Journal of Neuroscience, Journal of Neurophysiology and Brain Research or in engineering journals such as IEEE Transactions on Biomedical Engineering, IEEE Transactions on Neural Systems and Rehabilitation and Annals of Biomedical Engineering. There is no journal currently available focusing on the interdisciplinary field of neural engineering. In order to capitalize on the potential of neural engineering to investigate neural function and to solve problems related to neural disorders, it is necessary to break down the traditional barriers between neuroscientists and engineers not just in the laboratory but also in the publication of scientific papers. We do, therefore, need a new journal that provides a platform for this emerging interdisciplinary field of neural engineering where neuroscientists, neurobiologists and engineers can publish their work in one periodical that spans the disciplines. Journal of Neural Engineering will provide this platform. The new journal will publish full-length articles of the highest quality and importance in the field of neural engineering at the molecular, cellular and systems levels. The scope of Journal of Neural Engineering encompasses experimental, computational and theoretical aspects of neural interfacing, neuroelectronics, neuromechanical systems, neuroinformatics, neuroimaging, neural prostheses, artificial and biological neural circuits, neural control, neural tissue regeneration, neural signal processing, neural modeling and neuro-computation. The scope of the journal has both depth and breadth in areas relevant to the interface between neuroscience and engineering. There will be two Editors-in-Chief, with expertise covering both engineering and neuroscience. Experts in the areas encompassed by the journal's scope have been identified for the Editorial Board and the composition of the board will be continually updated to address the developments in this new and exciting field. The first issue of this new journal covers a variety of topics that combine neuroscience and engineering: mental state recognition from EEG signals, analysis of body motion in Parkinson's patients, non-linear dynamics of the respiratory system, automatic identification of saccade-related visual evoked potentials, multiple electrode stimulators, algorithms to estimate the causal relationship between brain sources, diffusion tensor imaging in the brain and phase synchronization of neural activity in vitro. This broad array of manuscripts focusing on neural imaging, neurophysiology, neural signal processing, neuroelectronics and neuro-dynamics can be found for the first time within the pages of a single journal: Journal of Neural Engineering. I am grateful to Institute of Physics Publishing and Jane Roscoe in particular for putting together this new journal to accommodate the fast-growing field of neural engineering. I am also grateful to Andrew Schwartz who has agreed to be the co-Editor-in-Chief for the journal.

Conditional bistability, a generic cellular mnemonic mechanism for robust and flexible working memory computations.

PubMed

Rodriguez, Guillaume; Sarazin, Matthieu; Clemente, Alexandra; Holden, Stephanie; Paz, Jeanne T; Delord, Bruno

2018-04-30

Persistent neural activity, the substrate of working memory, is thought to emerge from synaptic reverberation within recurrent networks. However, reverberation models do not robustly explain fundamental dynamics of persistent activity, including high-spiking irregularity, large intertrial variability, and state transitions. While cellular bistability may contribute to persistent activity, its rigidity appears incompatible with persistent activity labile characteristics. Here, we unravel in a cellular model a form of spike-mediated conditional bistability that is robust, generic and provides a rich repertoire of mnemonic computations. Under asynchronous synaptic inputs of the awakened state, conditional bistability generates spiking/bursting episodes, accounting for the irregularity, variability and state transitions characterizing persistent activity. This mechanism has likely been overlooked because of the sub-threshold input it requires and we predict how to assess it experimentally. Our results suggest a reexamination of the role of intrinsic properties in the collective network dynamics responsible for flexible working memory. SIGNIFICANCE STATEMENT This study unravels a novel form of intrinsic neuronal property, i.e. conditional bistability. We show that, thanks of its conditional character, conditional bistability favors the emergence of flexible and robust forms of persistent activity in PFC neural networks, in opposition to previously studied classical forms of absolute bistability. Specifically, we demonstrate for the first time that conditional bistability 1) is a generic biophysical spike-dependent mechanism of layer V pyramidal neurons in the PFC and that 2) it accounts for essential neurodynamical features for the organisation and flexibility of PFC persistent activity (the large irregularity and intertrial variability of the discharge and its organization under discrete stable states), which remain unexplained in a robust fashion by current models. Copyright © 2018 the authors.

Test-retest Reliability in Reporting the Pain Induced by a Pain Provocation Test: Further Validation of a Novel Approach for Pain Drawing Acquisition and Analysis.

PubMed

Leoni, Diego; Falla, Deborah; Heitz, Carolin; Capra, Gianpiero; Clijsen, Ron; Egloff, Michele; Cescon, Corrado; Baeyens, Jean-Pierre; Barbero, Marco

2017-02-01

Pain drawings (PD) are frequently used in research to illustrate the pain response to pain provocation tests. However, there is a lack of data on the reliability in defining the extent and location of pain. We investigated the test-retest reliability in reporting an acute painful sensation induced by a pain provocation test using a novel approach for PD acquisition and analysis in healthy volunteers. Forty healthy volunteers participated. Each participant underwent 2 upper limb neurodynamic tests 1 (ULNT1), once to the point of pain onset (PO) and once until the point of submaximal pain (SP). After each ULNT1, participants completed 2 consecutive PD with an interval of 1 minute. Custom software was used to quantify the pain extent and analyze the pain overlap. The test-retest reliability of pain extent was examined using Intraclass Correlation Coefficient (ICC 2,1 ) and Bland-Altman plots. Pain location reliability was examined using the Jaccard similarity coefficient (JSC). The ICC values for PO and SP were 0.98 (95% CI: 0.96-0.99) and 0.97 (95% CI: 0.95-0.98), respectively. The mean difference and 95% limits of agreement (± 1.96 SD) in the Bland-Altman plots were 14 pixels (-1080;1110) for PO, and 145 (-1610;1900) for SP. The median JSCs (Q1;Q3) were 0.73 (0.64;0.80) for PO and 0.76 (0.65;0.79) for SP. Pain drawings is a reliable instrument to investigate pain extent and pain location in healthy individuals experiencing an acute painful sensation induced by a pain provocation test. © 2016 World Institute of Pain.

Value of physical tests in diagnosing cervical radiculopathy: a systematic review.

PubMed

Thoomes, Erik J; van Geest, Sarita; van der Windt, Danielle A; Falla, Deborah; Verhagen, Arianne P; Koes, Bart W; Thoomes-de Graaf, Marloes; Kuijper, Barbara; Scholten-Peeters, Wendy G M; Vleggeert-Lankamp, Carmen L

2018-01-01

In clinical practice, the diagnosis of cervical radiculopathy is based on information from the patient's history, physical examination, and diagnostic imaging. Various physical tests may be performed, but their diagnostic accuracy is unknown. This study aimed to summarize and update the evidence on diagnostic performance of tests carried out during a physical examination for the diagnosis of cervical radiculopathy. A review of the accuracy of diagnostic tests was carried out. The study sample comprised diagnostic studies comparing results of tests performed during a physical examination in diagnosing cervical radiculopathy with a reference standard of imaging or surgical findings. Sensitivity, specificity, likelihood ratios are presented, together with pooled results for sensitivity and specificity. A literature search up to March 2016 was performed in CENTRAL, PubMed (MEDLINE), Embase, CINAHL, Web of Science, and Google Scholar. The methodological quality of studies was assessed using the QUADAS-2. Five diagnostic accuracy studies were identified. Only Spurling's test was evaluated in more than one study, showing high specificity ranging from 0.89 to 1.00 (95% confidence interval [CI]: 0.59-1.00); sensitivity varied from 0.38 to 0.97 (95% CI: 0.21-0.99). No studies were found that assessed the diagnostic accuracy of widely used neurological tests such as key muscle strength, tendon reflexes, and sensory impairments. There is limited evidence for accuracy of physical examination tests for the diagnosis of cervical radiculopathy. When consistent with patient history, clinicians may use a combination of Spurling's, axial traction, and an Arm Squeeze test to increase the likelihood of a cervical radiculopathy, whereas a combined results of four negative neurodynamics tests and an Arm Squeeze test could be used to rule out the disorder. Copyright © 2017 Elsevier Inc. All rights reserved.

Information theoretic measures of network coordination in high-frequency scalp EEG reveal dynamic patterns associated with seizure termination

PubMed Central

Stamoulis, Catherine; Schomer, Donald L.; Chang, Bernard S.

2013-01-01

How a seizure terminates is still under-studied and, despite its clinical importance, remains an obscure phase of seizure evolution. Recent studies of seizure-related scalp EEGs at frequencies >100 Hz suggest that neural activity, in the form of oscillations and/or neuronal network interactions, may play an important role in preictal/ictal seizure evolution [2, 31]. However, the role of high-frequency activity in seizure termination, is unknown, if it exists at all. Using information theoretic measures of network coordination, this study investigated ictal and immediate postictal neurodynamic interactions encoded in scalp EEGs from a relatively small sample of 8 patients with focal epilepsy and multiple seizures originating in temporal and/or frontal brain regions, at frequencies ≤100 Hz and >100 Hz, respectively. Despite some heterogeneity in the dynamics of these interactions, consistent patterns were also estimated. Specifically, in several seizures, linear or non-linear increase in high-frequency neuronal coordination during ictal intervals, coincided with a corresponding decrease in coordination at frequencies <100 Hz, suggesting a potential interference role of high-frequency activity, to disrupt abnormal ictal synchrony at lower frequencies. These changes in network synchrony started at least 20–30 sec prior to seizure offset, depending on the seizure duration. Opposite patterns were estimated at frequencies ≤100 Hz in several seizures. These results raise the possibility that high-frequency interference may occur in the form of progressive network coordination during the ictal interval, which continues during the postictal interval. This may be one of several possible mechanisms that facilitate seizure termination. In fact, inhibition of pairwise interactions between EEGs by other signals in their spatial neighborhood, quantified by negative interaction information, was estimated at frequencies ≤100 Hz, at least in some seizures. PMID:23608198

Fish Swim, Rocks Sit, and Lungs Breathe: Expert-Novice Understanding of Complex Systems

ERIC Educational Resources Information Center

Hmelo-Silver, Cindy E.; Marathe, Surabhi; Liu, Lei

2007-01-01

Understanding complex systems is fundamental to understanding science. The complexity of such systems makes them very difficult to understand because they are composed of multiple interrelated levels that interact in dynamic ways. The goal of this study was to understand how experts and novices differed in their understanding of two complex…

Understanding Complex Natural Systems by Articulating Structure-Behavior-Function Models

ERIC Educational Resources Information Center

Vattam, Swaroop S.; Goel, Ashok K.; Rugaber, Spencer; Hmelo-Silver, Cindy E.; Jordan, Rebecca; Gray, Steven; Sinha, Suparna

2011-01-01

Artificial intelligence research on creative design has led to Structure-Behavior-Function (SBF) models that emphasize functions as abstractions for organizing understanding of physical systems. Empirical studies on understanding complex systems suggest that novice understanding is shallow, typically focusing on their visible structures and…

Understanding terminological systems. II: Experience with conceptual and formal representation of structure.

PubMed

de Keizer, N F; Abu-Hanna, A

2000-03-01

This article describes the application of two popular conceptual and formal representation formalisms, as part of a framework for understanding terminological systems. A precise understanding of the structure of a terminological system is essential to assess existing terminological systems, to recognize patterns in various systems and to build new terminological systems. Our experience with the application of this framework to five well-known terminological systems is described.

"Wood already touched by fire is not hard to set alight": Comment on "Constraints to applying systems thinking concepts in health systems: A regional perspective from surveying stakeholders in Eastern Mediterranean countries".

PubMed

Agyepong, Irene Akua

2015-03-01

A major constraint to the application of any form of knowledge and principles is the awareness, understanding and acceptance of the knowledge and principles. Systems Thinking (ST) is a way of understanding and thinking about the nature of health systems and how to make and implement decisions within health systems to maximize desired and minimize undesired effects. A major constraint to applying ST within health systems in Low- and Middle-Income Countries (LMICs) would appear to be an awareness and understanding of ST and how to apply it. This is a fundamental constraint and in the increasing desire to enable the application of ST concepts in health systems in LMIC and understand and evaluate the effects; an essential first step is going to be enabling of a wide spread as well as deeper understanding of ST and how to apply this understanding.

A Framework for Understanding the Characteristics of Complexity in Biology

ERIC Educational Resources Information Center

Dauer, Joseph; Dauer, Jenny

2016-01-01

Understanding the functioning of natural systems is not easy, although there is general agreement that understanding complex systems is an important goal for science education. Defining what makes a natural system complex will assist in identifying gaps in research on student reasoning about systems. The goal of this commentary is to propose a…

Does Teaching Students How to Explicitly Model the Causal Structure of Systems Improve Their Understanding of These Systems?

ERIC Educational Resources Information Center

Jensen, Eva

2014-01-01

If students really understand the systems they study, they would be able to tell how changes in the system would affect a result. This demands that the students understand the mechanisms that drive its behaviour. The study investigates potential merits of learning how to explicitly model the causal structure of systems. The approach and…

Modeling systems-level dynamics: Understanding without mechanistic explanation in integrative systems biology.

PubMed

MacLeod, Miles; Nersessian, Nancy J

2015-02-01

In this paper we draw upon rich ethnographic data of two systems biology labs to explore the roles of explanation and understanding in large-scale systems modeling. We illustrate practices that depart from the goal of dynamic mechanistic explanation for the sake of more limited modeling goals. These processes use abstract mathematical formulations of bio-molecular interactions and data fitting techniques which we call top-down abstraction to trade away accurate mechanistic accounts of large-scale systems for specific information about aspects of those systems. We characterize these practices as pragmatic responses to the constraints many modelers of large-scale systems face, which in turn generate more limited pragmatic non-mechanistic forms of understanding of systems. These forms aim at knowledge of how to predict system responses in order to manipulate and control some aspects of them. We propose that this analysis of understanding provides a way to interpret what many systems biologists are aiming for in practice when they talk about the objective of a "systems-level understanding." Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterising the Development of the Understanding of Human Body Systems in High-School Biology Students--A Longitudinal Study

ERIC Educational Resources Information Center

Snapir, Zohar; Eberbach, Catherine; Ben-Zvi-Assaraf, Orit; Hmelo-Silver, Cindy; Tripto, Jaklin

2017-01-01

Science education today has become increasingly focused on research into complex natural, social and technological systems. In this study, we examined the development of high-school biology students' systems understanding of the human body, in a three-year longitudinal study. The development of the students' system understanding was evaluated…

Students' understanding of a groundwater system and attitudes towards groundwater use and conservation

NASA Astrophysics Data System (ADS)

Pan, Yi-Ting; Liu, Shu-Chiu

2018-03-01

The purpose of this study was to investigate students' understanding of groundwater as a system, and to further examine whether and how their understanding is related to attitudes towards groundwater use and conservation. A total of 676 junior high school students completed a groundwater survey including a drawing activity and a questionnaire. An additional group of university students with environmental science majors were recruited for the survey for the purpose of determining reasonable expectations and validating interpretations of the results. Analysis of student drawings indicated that students generally held an incomplete and unconnected understanding of the groundwater system. Correlation analysis showed that student levels of understanding were associated with their perceptions of environmental impacts as well as environmental concern regarding groundwater problems. These findings re-emphasised the importance of promoting students' understanding of environmental systems, as well as their ability to think systemically.

A diagnosis-based clinical decision rule for spinal pain part 2: review of the literature

PubMed Central

Murphy, Donald R; Hurwitz, Eric L; Nelson, Craig F

2008-01-01

Background Spinal pain is a common and often disabling problem. The research on various treatments for spinal pain has, for the most part, suggested that while several interventions have demonstrated mild to moderate short-term benefit, no single treatment has a major impact on either pain or disability. There is great need for more accurate diagnosis in patients with spinal pain. In a previous paper, the theoretical model of a diagnosis-based clinical decision rule was presented. The approach is designed to provide the clinician with a strategy for arriving at a specific working diagnosis from which treatment decisions can be made. It is based on three questions of diagnosis. In the current paper, the literature on the reliability and validity of the assessment procedures that are included in the diagnosis-based clinical decision rule is presented. Methods The databases of Medline, Cinahl, Embase and MANTIS were searched for studies that evaluated the reliability and validity of clinic-based diagnostic procedures for patients with spinal pain that have relevance for questions 2 (which investigates characteristics of the pain source) and 3 (which investigates perpetuating factors of the pain experience). In addition, the reference list of identified papers and authors' libraries were searched. Results A total of 1769 articles were retrieved, of which 138 were deemed relevant. Fifty-one studies related to reliability and 76 related to validity. One study evaluated both reliability and validity. Conclusion Regarding some aspects of the DBCDR, there are a number of studies that allow the clinician to have a reasonable degree of confidence in his or her findings. This is particularly true for centralization signs, neurodynamic signs and psychological perpetuating factors. There are other aspects of the DBCDR in which a lesser degree of confidence is warranted, and in which further research is needed. PMID:18694490

Information theoretic measures of network coordination in high-frequency scalp EEG reveal dynamic patterns associated with seizure termination.

PubMed

Stamoulis, Catherine; Schomer, Donald L; Chang, Bernard S

2013-08-01

How a seizure terminates is still under-studied and, despite its clinical importance, remains an obscure phase of seizure evolution. Recent studies of seizure-related scalp EEGs at frequencies >100 Hz suggest that neural activity, in the form of oscillations and/or neuronal network interactions, may play an important role in preictal/ictal seizure evolution (Andrade-Valenca et al., 2011; Stamoulis et al., 2012). However, the role of high-frequency activity in seizure termination, is unknown, if it exists at all. Using information theoretic measures of network coordination, this study investigated ictal and immediate postictal neurodynamic interactions encoded in scalp EEGs from a relatively small sample of 8 patients with focal epilepsy and multiple seizures originating in temporal and/or frontal brain regions, at frequencies ≤ 100 Hz and >100 Hz, respectively. Despite some heterogeneity in the dynamics of these interactions, consistent patterns were also estimated. Specifically, in several seizures, linear or non-linear increase in high-frequency neuronal coordination during ictal intervals, coincided with a corresponding decrease in coordination at frequencies <100 Hz, suggesting a potential interference role of high-frequency activity, to disrupt abnormal ictal synchrony at lower frequencies. These changes in network synchrony started at least 20-30s prior to seizure offset, depending on the seizure duration. Opposite patterns were estimated at frequencies ≤ 100 Hz in several seizures. These results raise the possibility that high-frequency interference may occur in the form of progressive network coordination during the ictal interval, which continues during the postictal interval. This may be one of several possible mechanisms that facilitate seizure termination. In fact, inhibition of pairwise interactions between EEGs by other signals in their spatial neighborhood, quantified by negative interaction information, was estimated at frequencies ≤ 100 Hz, at least in some seizures. Copyright © 2013 Elsevier B.V. All rights reserved.

Characterising the development of the understanding of human body systems in high-school biology students - a longitudinal study

NASA Astrophysics Data System (ADS)

Snapir, Zohar; Eberbach, Catherine; Ben-Zvi-Assaraf, Orit; Hmelo-Silver, Cindy; Tripto, Jaklin

2017-10-01

Science education today has become increasingly focused on research into complex natural, social and technological systems. In this study, we examined the development of high-school biology students' systems understanding of the human body, in a three-year longitudinal study. The development of the students' system understanding was evaluated using the Components Mechanisms Phenomena (CMP) framework for conceptual representation. We coded and analysed the repertory grid personal constructs of 67 high-school biology students at 4 points throughout the study. Our data analysis builds on the assumption that systems understanding entails a perception of all the system categories, including structures within the system (its Components), specific processes and interactions at the macro and micro levels (Mechanisms), and the Phenomena that present the macro scale of processes and patterns within a system. Our findings suggest that as the learning process progressed, the systems understanding of our students became more advanced, moving forward within each of the major CMP categories. Moreover, there was an increase in the mechanism complexity presented by the students, manifested by more students describing mechanisms at the molecular level. Thus, the 'mechanism' category and the micro level are critical components that enable students to understand system-level phenomena such as homeostasis.

Thai student existing understanding about the solar system model and the motion of the stars

NASA Astrophysics Data System (ADS)

Anantasook, Sakanan; Yuenyong, Chokchai

2018-01-01

The paper examined Thai student existing understanding about the solar system model and the motion of the stars. The participants included 141 Grade 9 students in four different schools of the Surin province, Thailand. Methodology regarded interpretive paradigm. The tool of interpretation included the Student Celestial Motion Conception Questionnaire (SCMCQ) and informal interview. Given understandings in the SCMCQ were read through and categorized according to students' understandings. Then, students were further probed as informal interview. Students' understandings in each category were counted and percentages computed. Finally, students' understandings across four different schools were compared and contrasted using the percentage of student responses in each category. The findings revealed that most students understand about Sun-Moon-Earth (SME) system and solar system model as well, they can use scientific explanations to explain the celestial objects in solar system and how they orbiting. Unfortunately, most of students (more than 70%) never know about the Polaris, the North Star, and 90.1% of them never know about the ecliptic, and probably also the 12 zodiac constellations. These existing understanding suggested some ideas of teaching and learning about solar system model and the motion of the stars. The paper, then, discussed some learning activities to enhance students to further construct meaning about solar system model and the motion of the stars.

Continuous whole-system monitoring toward rapid understanding of production HPC applications and systems

DOE PAGES

Agelastos, Anthony; Allan, Benjamin; Brandt, Jim; ...

2016-05-18

A detailed understanding of HPC applications’ resource needs and their complex interactions with each other and HPC platform resources are critical to achieving scalability and performance. Such understanding has been difficult to achieve because typical application profiling tools do not capture the behaviors of codes under the potentially wide spectrum of actual production conditions and because typical monitoring tools do not capture system resource usage information with high enough fidelity to gain sufficient insight into application performance and demands. In this paper we present both system and application profiling results based on data obtained through synchronized system wide monitoring onmore » a production HPC cluster at Sandia National Laboratories (SNL). We demonstrate analytic and visualization techniques that we are using to characterize application and system resource usage under production conditions for better understanding of application resource needs. Furthermore, our goals are to improve application performance (through understanding application-to-resource mapping and system throughput) and to ensure that future system capabilities match their intended workloads.« less

Discourse Understanding. Technical Report No. 391.

ERIC Educational Resources Information Center

Scha, R. J. H.; And Others

Artificial intelligence research on natural language understanding is discussed in this report using the notions that (1) natural language understanding systems must "see" sentences as elements whose significance resides in the contribution they make to the larger whole, and (2) a natural language understanding computer system must…

Understanding the Resilience of Socio-Ecological Systems to the Impacts from Chronic Pressures

EPA Science Inventory

As understanding of the resilience of social-ecological systems to disasters has increased, a concurrent understanding of the resilience of those systems to chronic problems has not. To address this need, the U.S. Environmental Protection Agency is piloting a research effort to f...

Promoting Conceptual Change for Complex Systems Understanding: Outcomes of an Agent-Based Participatory Simulation

NASA Astrophysics Data System (ADS)

Rates, Christopher A.; Mulvey, Bridget K.; Feldon, David F.

2016-08-01

Components of complex systems apply across multiple subject areas, and teaching these components may help students build unifying conceptual links. Students, however, often have difficulty learning these components, and limited research exists to understand what types of interventions may best help improve understanding. We investigated 32 high school students' understandings of complex systems components and whether an agent-based simulation could improve their understandings. Pretest and posttest essays were coded for changes in six components to determine whether students showed more expert thinking about the complex system of the Chesapeake Bay watershed. Results showed significant improvement for the components Emergence ( r = .26, p = .03), Order ( r = .37, p = .002), and Tradeoffs ( r = .44, p = .001). Implications include that the experiential nature of the simulation has the potential to support conceptual change for some complex systems components, presenting a promising option for complex systems instruction.

Earth Systems Education: Origins and Opportunities. Science Education for Global Understanding. Second Edition.

ERIC Educational Resources Information Center

University of Northern Colorado, Greeley.

This publication introduces and provides a framework for Earth Systems Education (ESE), an effort to establish within U.S. schools more effective programs designed to increase the public's understanding of the Earth system. The publication presents seven "understandings" around which curriculum can be organized and materials selected in…

Working the College System: Six Strategies for Building a Personal Powerbase

ERIC Educational Resources Information Center

Simplicio, Joseph S. C.

2008-01-01

Within each college system there are prescribed formalized methods for accomplishing tasks and achieving established goals. To truly understand how a college, or any large organization functions, it is vital to understand the basis of the formal structure. Those individuals who understand formal systems within a college can use this knowledge to…

How does undergraduate college biology students' level of understanding, in regard to the role of the seed plant root system, relate to their level of understanding of photosynthesis?

NASA Astrophysics Data System (ADS)

Njeng'ere, James Gicheha

This research study investigated how undergraduate college biology students' level of understanding of the role of the seed plant root system relates to their level of understanding of photosynthesis. This research was conducted with 65 undergraduate non-majors biology who had completed 1 year of biology at Louisiana State University in Baton Rouge and Southeastern Louisiana University in Hammond. A root probe instrument was developed from some scientifically acceptable propositional statements about the root system, the process of photosynthesis, as well as the holistic nature of the tree. These were derived from research reviews of the science education and the arboriculture literature. This was administered to 65 students selected randomly from class lists of the two institutions. Most of the root probe's items were based on the Live Oak tree. An in-depth, clinical interview-based analysis was conducted with 12 of those tested students. A team of root experts participated by designing, validating and answering the same questions that the students were asked. A "systems" lens as defined by a team of college instructors, root experts (Shigo, 1991), and this researcher was used to interpret the results. A correlational coefficient determining students' level of understanding of the root system and their level of understanding of the process of photosynthesis was established by means of Pearson's r correlation (r = 0.328) using the SAS statistical analysis (SAS, 1987). From this a coefficient of determination (r2 = 0.104) was determined. Students' level of understanding of the Live Oak root system (mean score 5.94) was not statistically different from their level of understanding of the process of photosynthesis (mean score 5.54) as assessed by the root probe, t (129) = 0.137, p > 0.05 one tailed-test. This suggests that, to some degree, level of the root system limits level of understanding of photosynthesis and vice versa. Analysis of quantitative and qualitative data revealed that students who applied principles of systems thinking performed better than those who did not. Students' understanding of the root system of the Live Oak tree was hindered by understanding of, plant food, the nonwoody roots, and the tree as a system.

Understanding Systems Theory for U.S. Marines

DTIC Science & Technology

2007-01-01

Combat Development Command Quantico, Virginia 22134-5068 FUTURE WAR Understanding Systems Theory for U.S. Marines SUBMITTED IN...Systems Theory for U.S. Marines 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...attached as Appendix C). Developing solutions requires understanding the problem( s ). In complex situations, some behavior of the target system

Systems Biology as an Integrated Platform for Bioinformatics, Systems Synthetic Biology, and Systems Metabolic Engineering

PubMed Central

Chen, Bor-Sen; Wu, Chia-Chou

2013-01-01

Systems biology aims at achieving a system-level understanding of living organisms and applying this knowledge to various fields such as synthetic biology, metabolic engineering, and medicine. System-level understanding of living organisms can be derived from insight into: (i) system structure and the mechanism of biological networks such as gene regulation, protein interactions, signaling, and metabolic pathways; (ii) system dynamics of biological networks, which provides an understanding of stability, robustness, and transduction ability through system identification, and through system analysis methods; (iii) system control methods at different levels of biological networks, which provide an understanding of systematic mechanisms to robustly control system states, minimize malfunctions, and provide potential therapeutic targets in disease treatment; (iv) systematic design methods for the modification and construction of biological networks with desired behaviors, which provide system design principles and system simulations for synthetic biology designs and systems metabolic engineering. This review describes current developments in systems biology, systems synthetic biology, and systems metabolic engineering for engineering and biology researchers. We also discuss challenges and future prospects for systems biology and the concept of systems biology as an integrated platform for bioinformatics, systems synthetic biology, and systems metabolic engineering. PMID:24709875

Systems biology as an integrated platform for bioinformatics, systems synthetic biology, and systems metabolic engineering.

PubMed

Chen, Bor-Sen; Wu, Chia-Chou

2013-10-11

Systems biology aims at achieving a system-level understanding of living organisms and applying this knowledge to various fields such as synthetic biology, metabolic engineering, and medicine. System-level understanding of living organisms can be derived from insight into: (i) system structure and the mechanism of biological networks such as gene regulation, protein interactions, signaling, and metabolic pathways; (ii) system dynamics of biological networks, which provides an understanding of stability, robustness, and transduction ability through system identification, and through system analysis methods; (iii) system control methods at different levels of biological networks, which provide an understanding of systematic mechanisms to robustly control system states, minimize malfunctions, and provide potential therapeutic targets in disease treatment; (iv) systematic design methods for the modification and construction of biological networks with desired behaviors, which provide system design principles and system simulations for synthetic biology designs and systems metabolic engineering. This review describes current developments in systems biology, systems synthetic biology, and systems metabolic engineering for engineering and biology researchers. We also discuss challenges and future prospects for systems biology and the concept of systems biology as an integrated platform for bioinformatics, systems synthetic biology, and systems metabolic engineering.

Understanding Digital Learning from the Perspective of Systems Dynamics

ERIC Educational Resources Information Center

Kok, Ayse

2009-01-01

The System Dynamics approach can be seen as a new way of understanding dynamical phenonema (natural, physical, biological, etc.) that occur in our daily lives taking into consideration not only single pairs of cause-effect variables, but the functioning of the system as a whole. This approach also provides the students with a new understanding in…

Conceptualizing Climate Change in the Context of a Climate System: Implications for Climate and Environmental Education

ERIC Educational Resources Information Center

Shepardson, Daniel P.; Niyogi, Dev; Roychoudhury, Anita; Hirsch, Andrew

2012-01-01

Today there is much interest in teaching secondary students about climate change. Much of this effort has focused directly on students' understanding of climate change. We hypothesize, however, that in order for students to understand climate change they must first understand climate as a system and how changes to this system due to both natural…

Enhanced Systemic Understanding of the Information Environment in Complex Crisis Management - Analytical Concept, Version 1.0

DTIC Science & Technology

2010-10-22

4. TITLE AND SUBTITLE Enhanced Systemic Understanding of the Information Environment in Complex Crisis Management Analytical Concept, Version 1.0...Email: schmidtb@iabg.de UNCLASSIFIED FOR PUBLIC RELEASE – Enhanced Systemic Understanding of the Information Environment in Complex Crisis ...multinational crisis management and the security sector about the significance and characteristics of the information environment. The framework is

Effect of Knowledge Integration Activities on Students' Perception of the Earth's Crust as a Cyclic System.

ERIC Educational Resources Information Center

Kali, Yael; Orion, Nir; Eylon, Bat-Sheva

2003-01-01

Characterizes students' understanding of the rock cycle system. Examines effects of a knowledge integration activity on their system thinking. Interprets answers to an open-ended test using a systems thinking continuum ranging from a completely static view of the system to an understanding of the system's cyclic nature. Reports meaningful…

Systems biology approach to bioremediation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakraborty, Romy; Wu, Cindy H.; Hazen, Terry C.

2012-06-01

Bioremediation has historically been approached as a ‘black box’ in terms of our fundamental understanding. Thus it succeeds and fails, seldom without a complete understanding of why. Systems biology is an integrated research approach to study complex biological systems, by investigating interactions and networks at the molecular, cellular, community, and ecosystem level. The knowledge of these interactions within individual components is fundamental to understanding the dynamics of the ecosystem under investigation. Finally, understanding and modeling functional microbial community structure and stress responses in environments at all levels have tremendous implications for our fundamental understanding of hydrobiogeochemical processes and the potentialmore » for making bioremediation breakthroughs and illuminating the ‘black box’.« less

Systems genetics approaches to understand complex traits

PubMed Central

Civelek, Mete; Lusis, Aldons J.

2014-01-01

Systems genetics is an approach to understand the flow of biological information that underlies complex traits. It uses a range of experimental and statistical methods to quantitate and integrate intermediate phenotypes, such as transcript, protein or metabolite levels, in populations that vary for traits of interest. Systems genetics studies have provided the first global view of the molecular architecture of complex traits and are useful for the identification of genes, pathways and networks that underlie common human diseases. Given the urgent need to understand how the thousands of loci that have been identified in genome-wide association studies contribute to disease susceptibility, systems genetics is likely to become an increasingly important approach to understanding both biology and disease. PMID:24296534

Speech Understanding with a New Implant Technology: A Comparative Study with a New Nonskin Penetrating Baha System

PubMed Central

Caversaccio, Marco

2014-01-01

Objective. To compare hearing and speech understanding between a new, nonskin penetrating Baha system (Baha Attract) to the current Baha system using a skin-penetrating abutment. Methods. Hearing and speech understanding were measured in 16 experienced Baha users. The transmission path via the abutment was compared to a simulated Baha Attract transmission path by attaching the implantable magnet to the abutment and then by adding a sample of artificial skin and the external parts of the Baha Attract system. Four different measurements were performed: bone conduction thresholds directly through the sound processor (BC Direct), aided sound field thresholds, aided speech understanding in quiet, and aided speech understanding in noise. Results. The simulated Baha Attract transmission path introduced an attenuation starting from approximately 5 dB at 1000 Hz, increasing to 20–25 dB above 6000 Hz. However, aided sound field threshold shows smaller differences and aided speech understanding in quiet and in noise does not differ significantly between the two transmission paths. Conclusion. The Baha Attract system transmission path introduces predominately high frequency attenuation. This attenuation can be partially compensated by adequate fitting of the speech processor. No significant decrease in speech understanding in either quiet or in noise was found. PMID:25140314

Embodied experiences for science learning: A cognitive linguistics exploration of middle school students' language in learning about water

NASA Astrophysics Data System (ADS)

Salinas Barrios, Ivan Eduardo

I investigated linguistic patterns in middle school students' writing to understand their relevant embodied experiences for learning science. Embodied experiences are those limited by the perceptual and motor constraints of the human body. Recent research indicates student understanding of science needs embodied experiences. Recent emphases of science education researchers in the practices of science suggest that students' understanding of systems and their structure, scale, size, representations, and causality are crosscutting concepts that unify all scientific disciplinary areas. To discern the relationship between linguistic patterns and embodied experiences, I relied on Cognitive Linguistics, a field within cognitive sciences that pays attention to language organization and use assuming that language reflects the human cognitive system. Particularly, I investigated the embodied experiences that 268 middle school students learning about water brought to understanding: i) systems and system structure; ii) scale, size and representations; and iii) causality. Using content analysis, I explored students' language in search of patterns regarding linguistic phenomena described within cognitive linguistics: image schemas, conceptual metaphors, event schemas, semantical roles, and force-dynamics. I found several common embodied experiences organizing students' understanding of crosscutting concepts. Perception of boundaries and change in location and perception of spatial organization in the vertical axis are relevant embodied experiences for students' understanding of systems and system structure. Direct object manipulation and perception of size with and without locomotion are relevant for understanding scale, size and representations. Direct applications of force and consequential perception of movement or change in form are relevant for understanding of causality. I discuss implications of these findings for research and science teaching.

48 CFR 316.770-2 - Memoranda of understanding.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Memoranda of understanding. 316.770-2 Section 316.770-2 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... contrary to the language of the solicitation or prospective contract. A memorandum of understanding does...

48 CFR 316.770-2 - Memoranda of understanding.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Memoranda of understanding. 316.770-2 Section 316.770-2 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... contrary to the language of the solicitation or prospective contract. A memorandum of understanding does...

48 CFR 316.770-2 - Memoranda of understanding.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Memoranda of understanding. 316.770-2 Section 316.770-2 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... contrary to the language of the solicitation or prospective contract. A memorandum of understanding does...

48 CFR 316.770-2 - Memoranda of understanding.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Memoranda of understanding. 316.770-2 Section 316.770-2 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... contrary to the language of the solicitation or prospective contract. A memorandum of understanding does...

48 CFR 316.770-2 - Memoranda of understanding.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Memoranda of understanding. 316.770-2 Section 316.770-2 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... contrary to the language of the solicitation or prospective contract. A memorandum of understanding does...

Indigenous Knowledge - A Holistic View Through a Food Security Lens

NASA Astrophysics Data System (ADS)

Angnaboogok, V.; Behe, C.; Daniel, R. G.

2017-12-01

Rapid changes occurring within the Arctic heighten the need to understand the multiple drivers pushing change and their cumulative impacts. Most importantly to better understand Arctic change a holistic view is needed that can only be achieved through bringing together multiple knowledge systems and scientific disciplines. Inuit have called the Arctic home from time immemorial acquiring a knowledge system. The Inuit knowledge system continues to grow, and holds methodologies and assessment processes that provide a pathway for holistically understanding the Arctic. This holistic view is largely attributed to a focus on relationships between system components, close attention to food webs, and a unique understanding of interconnecting systems. The Alaskan Inuit understanding of food security represents an Indigenous way of viewing the world - where food security encompasses complex and interlinked cultural and environmental systems. These systems are comprised of connections among the health of people, animals, and plants; the different states of land, sea, and air; and the cultural fabric held together by language, cultural expression, and social integrity. Within the Inuit knowledge system, it is impossible to disentangle some of these relationships; when we discuss an Inuit food security perspective, it is this interconnectivity and these relationships that we refer to. This presentation will offer an introduction to what it means to adopt a food security lens approach - a view needed to build our knowledge of the changes that are occurring and further our understanding of cumulative impacts while illuminating the nexus between all pieces that make up Arctic ecosystems.

How Information Visualization Systems Change Users' Understandings of Complex Data

ERIC Educational Resources Information Center

Allendoerfer, Kenneth Robert

2009-01-01

User-centered evaluations of information systems often focus on the usability of the system rather its usefulness. This study examined how a using an interactive knowledge-domain visualization (KDV) system affected users' understanding of a domain. Interactive KDVs allow users to create graphical representations of domains that depict important…

A Preliminary Comparison of Student and Professional Motivations for Choosing Information Systems

ERIC Educational Resources Information Center

Brooks, Nita; Korzaan, Melinda; Ceccucci, Wendy

2014-01-01

Demand for qualified information systems professionals continues to rise. Additionally, over the past decade, enrollment in information systems-related educational programs has declined. In order to understand why and to better understand how to position information systems undergraduate programs to recruit and retain students, this study provides…

Understanding Transportation Systems : An Integrated Approach to Modeling Complex Transportation Systems

DOT National Transportation Integrated Search

2013-01-01

The ability to model and understand the complex dynamics of intelligent agents as they interact within a transportation system could lead to revolutionary advances in transportation engineering and intermodal surface transportation in the United Stat...

Assessing Understanding of Complex Causal Networks Using an Interactive Game

ERIC Educational Resources Information Center

Ross, Joel

2013-01-01

Assessing people's understanding of the causal relationships found in large-scale complex systems may be necessary for addressing many critical social concerns, such as environmental sustainability. Existing methods for assessing systems thinking and causal understanding frequently use the technique of cognitive causal mapping. However, the…

Five Lectures on Artificial Intelligence

DTIC Science & Technology

1974-09-01

large systems The current projects on speech understanding (which I will describe iater) are an exception to this, dealing explicitly with the problem...learns that "Fred lives in Sydney", we must find some new fact to resolve the tension — 1 SPEECH UNDERSTANDING SYSTEMS perhaps he lives in a zco It is...possible Speech Understanding Systems Most of the problems described above might be characterized as relating to the chunking of knowledge. Such ideas are

Impact of Three-Dimensional Printed Pelvicaliceal System Models on Residents' Understanding of Pelvicaliceal System Anatomy Before Percutaneous Nephrolithotripsy Surgery: A Pilot Study.

PubMed

Atalay, Hasan Anıl; Ülker, Volkan; Alkan, İlter; Canat, Halil Lütfi; Özkuvancı, Ünsal; Altunrende, Fatih

2016-10-01

To investigate the impact of three-dimensional (3D) printed pelvicaliceal system models on residents' understanding of pelvicaliceal system anatomy before percutaneous nephrolithotripsy (PCNL). Patients with unilateral complex renal stones indicating PCNL were selected. Usable data of patients were obtained from CT-scans in Digital Imaging and Communications in Medicine (DICOM) format. Mimics software version 16.0 (Materialise, Belgium) was used for segmentation and extraction of pelvicaliceal systems (PCSs). All DICOM-formatted files were converted to the stereolithography file format. Finally, fused deposition modeling was used to create plasticine 3D models of PCSs. A questionnaire was designed so that residents could assess the 3D models' effects on their understanding of the anatomy of the pelvicaliceal system before PCNL (Fig. 3). Five patients' anatomically accurate models of the human renal collecting system were effectively generated (Figs. 1 and 2). After presentation of the 3D models, residents were 86% and 88% better at determining the number of anterior and posterior calices, respectively, 60% better at understanding stone location, and 64% better at determining optimal entry calix into the collecting system (Fig. 5). Generating kidney models of PCSs using 3D printing technology is feasible, and the models were accepted by residents as aids in surgical planning and understanding of pelvicaliceal system anatomy before PCNL.

Moving through the Solar System: Using Movement Activities To Learn about the Solar System.

ERIC Educational Resources Information Center

Nygard, Bonnie; Shaw, Donna Gail

1997-01-01

Presents a rationale for acknowledging the importance of movement to learning to help children understand abstract concepts. Includes seven activities that employ movement to enable students to understand the nature of the solar system. (DDR)

How Well Do Students in Secondary School Understand Temporal Development of Dynamical Systems?

ERIC Educational Resources Information Center

Forjan, Matej; Grubelnik, Vladimir

2015-01-01

Despite difficulties understanding the dynamics of complex systems only simple dynamical systems without feedback connections have been taught in secondary school physics. Consequently, students do not have opportunities to develop intuition of temporal development of systems, whose dynamics are conditioned by the influence of feedback processes.…

Covering the Bases: Exploring Alternative Systems

ERIC Educational Resources Information Center

Kurz, Terri L.; Garcia, Jorge

2015-01-01

Since the 1950s, the understanding of how the base 10 system works has been encouraged through alternative base systems (Price 1995; Woodward 2004). If high school students are given opportunities to learn other base systems and analyze what they denote, we believe that they will better understand the structure of base 10 and its operations…

Using Simulations in Linked Courses to Foster Student Understanding of Complex Political Institutions

ERIC Educational Resources Information Center

Williams, Michelle Hale

2015-01-01

Political institutions provide basic building blocks for understanding and comparing political systems. Yet, students often struggle to understand the implications of institutional choice, such as electoral system rules, especially when the formulas and calculations used to determine seat allocation can be multilevel and complex. This study brings…

Students' Understandings of Human Organs and Organ Systems.

ERIC Educational Resources Information Center

Reiss, Michael J.; Tunnicliffe, Sue Dale

2001-01-01

Discusses students' understandings of their own internal structure. Analysis shows the extent to which student understanding increases with age and the degree to which students know more about some organs and organ systems than others. Gender differences in the drawings were generally not large and there were some intriguing differences in the…

Exploring Students' Understanding of Ordinary Differential Equations Using Computer Algebraic System (CAS)

ERIC Educational Resources Information Center

Maat, Siti Mistima; Zakaria, Effandi

2011-01-01

Ordinary differential equations (ODEs) are one of the important topics in engineering mathematics that lead to the understanding of technical concepts among students. This study was conducted to explore the students' understanding of ODEs when they solve ODE questions using a traditional method as well as a computer algebraic system, particularly…

Promoting Conceptual Change for Complex Systems Understanding: Outcomes of an Agent-Based Participatory Simulation

ERIC Educational Resources Information Center

Rates, Christopher A.; Mulvey, Bridget K.; Feldon, David F.

2016-01-01

Components of complex systems apply across multiple subject areas, and teaching these components may help students build unifying conceptual links. Students, however, often have difficulty learning these components, and limited research exists to understand what types of interventions may best help improve understanding. We investigated 32 high…

Getting the lead out: understanding risks in the distribution system

EPA Science Inventory

This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation me...

From Global Sustainability to Inclusive Education: Understanding urban children's ideas about the food system

NASA Astrophysics Data System (ADS)

Calabrese Barton, Angela; Koch, Pamela D.; Contento, Isobel R.; Hagiwara, Sumi

2005-08-01

The purpose of this paper is to report our findings from a qualitative study intended to develop our understandings of: what high-poverty urban children understand and believe about food and food systems; and how such children transform and use that knowledge in their everyday lives (i.e. how do they express their scientific literacies including content understandings, process understandings, habits of mind in these content areas). This qualitative study is part of a larger study focused on understanding and developing science and nutritional literacies among high-poverty urban fourth-grade through sixth-grade students and their teachers and caregivers.

Developing Students' Understanding of Complex Systems in the Geosciences (Invited)

NASA Astrophysics Data System (ADS)

Manduca, C. A.; Mogk, D. W.; Bice, D. M.; Pyle, E.; Slotta, J.

2010-12-01

Developing a systems perspective is a commonly cited goal for geosciences courses and programs. This perspective is a powerful tool for critical thinking, problem solving and integrative thinking across and beyond the sciences. In April 2010, a NSF funded ‘On the Cutting Edge’ workshop brought together 45 geoscience faculty, education and cognitive science researchers, and faculty from other STEM and social science disciplines that make use of a complex systems approach. The workshop participants focused on understanding the challenges inherent in developing an understanding of complex systems and the teaching strategies currently in use across the disciplines. These include using models and visualizations to allow students to experiment with complex systems, using projects and problems to give students experience with data and observations derived from a complex system, and using illustrated lectures and discussions and analogies to illuminate the salient aspects of complex systems. The workshop website contains a collection of teaching activities, instructional resources and courses that demonstrate these approaches. The workshop participants concluded that research leading to a clear articulation of what constitutes understanding complex system behavior is needed, as are instruments and performance measures that could be used to assess this understanding. Developing the ability to recognize complex systems and understand their behavior is a significant learning task that cannot be achieved in a single course. Rather it is a type of literacy that should be taught in a progression extending from elementary school to college and across the disciplines. Research defining this progression and its endpoints is needed. Full information about the workshop, its discussions, and resulting collections of courses, activities, references and ideas are available on the workshop website.

Thiol/disulfide redox states in signaling and sensing

PubMed Central

Go, Young-Mi; Jones, Dean P.

2015-01-01

Rapid advances in redox systems biology are creating new opportunities to understand complexities of human disease and contributions of environmental exposures. New understanding of thiol-disulfide systems have occurred during the past decade as a consequence of the discoveries that thiol and disulfide systems are maintained in kinetically controlled steady-states displaced from thermodynamic equilibrium, that a widely distributed family of NADPH oxidases produces oxidants that function in cell signaling, and that a family of peroxiredoxins utilize thioredoxin as a reductant to complement the well-studied glutathione antioxidant system for peroxide elimination and redox regulation. This review focuses on thiol/disulfide redox state in biologic systems and the knowledge base available to support development of integrated redox systems biology models to better understand the function and dysfunction of thiol-disulfide redox systems. In particular, central principles have emerged concerning redox compartmentalization and utility of thiol/disulfide redox measures as indicators of physiologic function. Advances in redox proteomics show that, in addition to functioning in protein active sites and cell signaling, cysteine residues also serve as redox sensors to integrate biologic functions. These advances provide a framework for translation of redox systems biology concepts to practical use in understanding and treating human disease. Biological responses to cadmium, a widespread environmental agent, are used to illustrate the utility of these advances to the understanding of complex pleiotropic toxicities. PMID:23356510

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agelastos, Anthony; Allan, Benjamin; Brandt, Jim

A detailed understanding of HPC applications’ resource needs and their complex interactions with each other and HPC platform resources are critical to achieving scalability and performance. Such understanding has been difficult to achieve because typical application profiling tools do not capture the behaviors of codes under the potentially wide spectrum of actual production conditions and because typical monitoring tools do not capture system resource usage information with high enough fidelity to gain sufficient insight into application performance and demands. In this paper we present both system and application profiling results based on data obtained through synchronized system wide monitoring onmore » a production HPC cluster at Sandia National Laboratories (SNL). We demonstrate analytic and visualization techniques that we are using to characterize application and system resource usage under production conditions for better understanding of application resource needs. Furthermore, our goals are to improve application performance (through understanding application-to-resource mapping and system throughput) and to ensure that future system capabilities match their intended workloads.« less

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXIII, I--MAINTAINING THE FUEL SYSTEM, PART II--CATERPILLAR DIESEL ENGINE, II--UNDERSTANDING STEERING SYSTEMS.

ERIC Educational Resources Information Center

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE FUEL INJECTION SYSTEM AND THE STEERING SYSTEM OF DIESEL POWERED VEHICLES. TOPICS ARE FUEL INJECTION SECTION, AND DESCRIPTION OF THE STEERING SYSTEM. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL BRANCH PROGRAMED TRAINING…

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XIII, I--MAINTAINING THE FUEL SYSTEM (PART III), CUMMINS DIESEL ENGINES, II--RADIATOR SHUTTER SYSTEM.

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE CONSTRUCTION, OPERATION, AND MAINTENANCE OF THE DIESEL ENGINE FUEL AND RADIATOR SHUTTER SYSTEMS. TOPICS ARE (1) MORE ABOUT THE CUMMINS FUEL SYSTEM, (2) CALIBRATING THE PT FUEL PUMP, (3) CALIBRATING THE FUEL INJECTORS, (4) UNDERSTANDING THE SHUTTER SYSTEM, (5) THE…

System Simulation Modeling: A Case Study Illustration of the Model Development Life Cycle

Treesearch

Janice K. Wiedenbeck; D. Earl Kline

1994-01-01

Systems simulation modeling techniques offer a method of representing the individual elements of a manufacturing system and their interactions. By developing and experimenting with simulation models, one can obtain a better understanding of the overall physical system. Forest products industries are beginning to understand the importance of simulation modeling to help...

Implementation of an Adaptive Learning System Using a Bayesian Network

ERIC Educational Resources Information Center

Yasuda, Keiji; Kawashima, Hiroyuki; Hata, Yoko; Kimura, Hiroaki

2015-01-01

An adaptive learning system is proposed that incorporates a Bayesian network to efficiently gauge learners' understanding at the course-unit level. Also, learners receive content that is adapted to their measured level of understanding. The system works on an iPad via the Edmodo platform. A field experiment using the system in an elementary school…

[Influence of mixing ratios of a FM-system on speech understanding of CI-users].

PubMed

Hey, M; Anft, D; Hocke, T; Scholz, G; Hessel, H; Begall, K

2009-05-01

At school we find two major acoustic situations: (first) the "teacher is talking" being disturbed by the pupils making noise and (second) another "pupil is talking" disturbed by other pupils. The understanding of words and sentences in hearing impaired patients with a cochlear implant (CI) in a noisy situation can be improved by using a FM system. The aim of this study is to test speech understanding depending on mixing ratios between FM input and microphone input to the speech processor in different circumstances. Speech understanding was evaluated using the adaptive Oldenburger sentence test (OLSA) in background noise. CI patients used the FM system Microlink for Freedom CIs together with a Campus transmitter (Phonak AG). 17 postlingually deafened adults were tested, using unilateral Freedom cochlear implant systems (Cochlear Ltd). A group of eight normally hearing adults was used as a control group in the same setup. We found that the median value of L (50)=1.6 dB in CI patients without a FM system is higher than the median value of L(50)=-13 dB in normally hearing subjects. The sentence recognition in CI patients with FM system increased with increasing mixing ratio. The benefit using the FM system to understand the teacher is of high advantage in any mixing ratio. The difference between the L(50) values in situations with or without a FM-system is 15 dB for the mixing ratio 3:1 (FM to microphone). If we take into account an increase of 15% per dB in the OLSA (at L(50)) in CI patients, the difference of 15 dB means a calculated advantage of 225%. The speech understanding during the second condition ("pupil is talking") however remained nearly the same in all used mixing ratios. The calculations showed no statistical difference between these situations with and without a FM system. The speaker comprehension for the two investigated listening conditions showed different results. Understanding in the "teacher is talking" situation increased with increasing mixing ratio (FM to microphone) and in the "pupil is talking" situation remained on the same level. We could not find an optimal FM setting for both listening conditions. This leads to different suggestions for different listening conditions. All patients showed an increased speech understanding in noisy environments. This result strongly encourages the use of a FM-system in a classroom.

Students' Understanding of a Groundwater System and Attitudes towards Groundwater Use and Conservation

ERIC Educational Resources Information Center

Pan, Yi-Ting; Liu, Shu-Chiu

2018-01-01

The purpose of this study was to investigate students' understanding of groundwater as a system, and to further examine whether and how their understanding is related to attitudes towards groundwater use and conservation. A total of 676 junior high school students completed a groundwater survey including a drawing activity and a questionnaire. An…

Approaches for scalable modeling and emulation of cyber systems : LDRD final report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayo, Jackson R.; Minnich, Ronald G.; Armstrong, Robert C.

2009-09-01

The goal of this research was to combine theoretical and computational approaches to better understand the potential emergent behaviors of large-scale cyber systems, such as networks of {approx} 10{sup 6} computers. The scale and sophistication of modern computer software, hardware, and deployed networked systems have significantly exceeded the computational research community's ability to understand, model, and predict current and future behaviors. This predictive understanding, however, is critical to the development of new approaches for proactively designing new systems or enhancing existing systems with robustness to current and future cyber threats, including distributed malware such as botnets. We have developed preliminarymore » theoretical and modeling capabilities that can ultimately answer questions such as: How would we reboot the Internet if it were taken down? Can we change network protocols to make them more secure without disrupting existing Internet connectivity and traffic flow? We have begun to address these issues by developing new capabilities for understanding and modeling Internet systems at scale. Specifically, we have addressed the need for scalable network simulation by carrying out emulations of a network with {approx} 10{sup 6} virtualized operating system instances on a high-performance computing cluster - a 'virtual Internet'. We have also explored mappings between previously studied emergent behaviors of complex systems and their potential cyber counterparts. Our results provide foundational capabilities for further research toward understanding the effects of complexity in cyber systems, to allow anticipating and thwarting hackers.« less

Modeling Earth's Climate

ERIC Educational Resources Information Center

Pallant, Amy; Lee, Hee-Sun; Pryputniewicz, Sara

2012-01-01

Systems thinking suggests that one can best understand a complex system by studying the interrelationships of its component parts rather than looking at the individual parts in isolation. With ongoing concern about the effects of climate change, using innovative materials to help students understand how Earth's systems connect with each other is…

A protocol for parameterization and calibration of RZWQM2 in field research

USDA-ARS?s Scientific Manuscript database

Use of agricultural system models in field research requires a full understanding of both the model and the system it simulates. Since the 1960s, agricultural system models have increased tremendously in their complexity due to greater understanding of the processes simulated, their application to r...

Understanding Air-Liquid Interface Cell Exposure Systems: A Comprehensive Assessment of Various Systems Under Identical Conditions

EPA Science Inventory

Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI system design features that permit reproducible a...

Children's and Adolescents' Thoughts on Pollution: Cognitive Abilities Required to Understand Environmental Systems

ERIC Educational Resources Information Center

Rodríguez, Manuel; Kohen, Raquel; Delval, Juan

2015-01-01

Pollution phenomena are complex systems in which different parts are integrated by means of causal and temporal relationships. To understand pollution, children must develop some cognitive abilities related to system thinking and temporal and causal inferential reasoning. These cognitive abilities constrain and guide how children understand…

A systems biology approach to understanding impacts of environmental contaminants on fish reproduction

EPA Science Inventory

Over the past decade, our research team at the US EPA Mid-Continent Ecology Division has employed systems biology approaches to examine and understand impacts of environmental contaminants on fish reproduction. Our systems biology approach is one in which iterations of model cons...

Understanding Time-driven Activity-based Costing.

PubMed

Sharan, Alok D; Schroeder, Gregory D; West, Michael E; Vaccaro, Alexander R

2016-03-01

Transitioning to a value-based health care system will require providers to increasingly scrutinize their outcomes and costs. Although there has been a great deal of effort to understand outcomes, cost accounting in health care has been a greater challenge. Currently the cost accounting methods used by hospitals and providers are based off a fee-for-service system. As resources become increasingly scarce and the health care system attempts to understand which services provide the greatest value, it will be critically important to understand the true costs of delivering a service. An understanding of the true costs of a particular service will help providers make smarter decisions on how to allocate and utilize resources as well as determine which activities are nonvalue added. Achieving value will require providers to have a greater focus on accurate outcome data as well as better methods of cost accounting.

In situ Probe Science at Saturn

NASA Technical Reports Server (NTRS)

Atkinson, D.H.; Lunine, J.I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.;

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXIV, I--MAINTAINING THE FUEL SYSTEM PART III--CATERPILLAR DIESEL ENGINE, II--UNDERSTANDING THE VOLTAGE REGULATOR/ALTERNATOR.

ERIC Educational Resources Information Center

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE FUEL AND BATTERY CHARGING SYSTEM. TOPICS ARE (1) INJECTION TIMING CONTROLS, (2) GOVERNOR, (3) FUEL SYSTEM MAINTENANCE TIPS, (4) THE CHARGING SYSTEM, (5) REGULATING THE GENERATOR/ALTERNATOR, AND (6) CHARGING SYSTEM SERVICE…

Understanding Infusion Pumps.

PubMed

Mandel, Jeff E

2018-04-01

Infusion systems are complicated electromechanical systems that are used to deliver anesthetic drugs with moderate precision. Four types of systems are described-gravity feed, in-line piston, peristaltic, and syringe. These systems are subject to a number of failure modes-occlusion, disconnection, siphoning, infiltration, and air bubbles. The relative advantages of the various systems and some of the monitoring capabilities are discussed. A brief example of the use of an infusion system during anesthetic induction is presented. With understanding of the functioning of these systems, users may develop greater comfort.

CDC Vital Signs: Cervical Cancer is Preventable

MedlinePlus

... die of cervical cancer. Doctors, nurses, and health systems can: Help women understand what screening tests are ... Title X Family Planning Doctors, nurses, and health systems can Help women understand which screening tests are ...

Health care organizations as complex systems: new perspectives on design and management.

PubMed

McDaniel, Reuben R; Driebe, Dean J; Lanham, Holly Jordan

2013-01-01

We discuss the impact of complexity science on the design and management of health care organizations over the past decade. We provide an overview of complexity science issues and their impact on thinking about health care systems, particularly with the rising importance of information systems. We also present a complexity science perspective on current issues in today's health care organizations and suggest ways that this perspective might help in approaching these issues. We review selected research, focusing on work in which we participated, to identify specific examples of applications of complexity science. We then take a look at information systems in health care organizations from a complexity viewpoint. Complexity science is a fundamentally different way of understanding nature and has influenced the thinking of scholars and practitioners as they have attempted to understand health care organizations. Many scholars study health care organizations as complex adaptive systems and through this perspective develop new management strategies. Most important, perhaps, is the understanding that attention to relationships and interdependencies is critical for developing effective management strategies. Increased understanding of complexity science can enhance the ability of researchers and practitioners to develop new ways of understanding and improving health care organizations. This analysis opens new vistas for scholars and practitioners attempting to understand health care organizations as complex adaptive systems. The analysis holds value for those already familiar with this approach as well as those who may not be as familiar.

First-Year Medical Students' Conceptual Understanding of and Resistance to Conceptual Change Concerning the Central Cardiovascular System

ERIC Educational Resources Information Center

Mikkila-Erdmann, Mirjamaija; Sodervik, Ilona; Vilppu, Henna; Kaapa, Pekka; Olkinuora, Erkki

2012-01-01

Medical students often have initial understanding concerning medical domains, such as the central cardiovascular system (CCVS), when they enter the study programme. These notions may to some extent be in conflict with scientific understanding, which can be seen as a challenge for medical teaching. Hence, the purpose of this study was to analyse…

An association account of false belief understanding.

PubMed

De Bruin, L C; Newen, A

2012-05-01

The elicited-response false belief task has traditionally been considered as reliably indicating that children acquire an understanding of false belief around 4 years of age. However, recent investigations using spontaneous-response tasks suggest that false belief understanding emerges much earlier. This leads to a developmental paradox: if young infants already understand false belief, then why do they fail the elicited-response false belief task? We postulate two systems to account for the development of false belief understanding: an association module, which provides infants with the capacity to register congruent associations between agents and objects, and an operating system, which allows them to transform these associations into incongruent associations through a process of inhibition, selection and representation. The interaction between the association module and the operating system enables infants to register increasingly complex associations on the basis of another agent's movements, visual perspective and propositional attitudes. This allows us account for the full range of findings on false belief understanding. Copyright © 2012 Elsevier B.V. All rights reserved.

Automated Sensor Tuning for Seismic Event Detection at a Carbon Capture, Utilization, and Storage Site, Farnsworth Unit, Ochiltree County, Texas

NASA Astrophysics Data System (ADS)

Ziegler, A.; Balch, R. S.; Knox, H. A.; Van Wijk, J. W.; Draelos, T.; Peterson, M. G.

2016-12-01

We present results (e.g. seismic detections and STA/LTA detection parameters) from a continuous downhole seismic array in the Farnsworth Field, an oil field in Northern Texas that hosts an ongoing carbon capture, utilization, and storage project. Specifically, we evaluate data from a passive vertical monitoring array consisting of 16 levels of 3-component 15Hz geophones installed in the field and continuously recording since January 2014. This detection database is directly compared to ancillary data (i.e. wellbore pressure) to determine if there is any relationship between seismic observables and CO2 injection and pressure maintenance in the field. Of particular interest is detection of relatively low-amplitude signals constituting long-period long-duration (LPLD) events that may be associated with slow shear-slip analogous to low frequency tectonic tremor. While this category of seismic event provides great insight into dynamic behavior of the pressurized subsurface, it is inherently difficult to detect. To automatically detect seismic events using effective data processing parameters, an automated sensor tuning (AST) algorithm developed by Sandia National Laboratories is being utilized. AST exploits ideas from neuro-dynamic programming (reinforcement learning) to automatically self-tune and determine optimal detection parameter settings. AST adapts in near real-time to changing conditions and automatically self-tune a signal detector to identify (detect) only signals from events of interest, leading to a reduction in the number of missed legitimate event detections and the number of false event detections. Funding for this project is provided by the U.S. Department of Energy's (DOE) National Energy Technology Laboratory (NETL) through the Southwest Regional Partnership on Carbon Sequestration (SWP) under Award No. DE-FC26-05NT42591. Additional support has been provided by site operator Chaparral Energy, L.L.C. and Schlumberger Carbon Services. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

From the Field to the Classroom: Developing Scientifically Literate Citizens Using the Understanding Global Change Framework in Education and Citizen Science

NASA Astrophysics Data System (ADS)

Toupin, C.; Bean, J. R.; Gavenus, K.; Johnson, H.; Toupin, S.

2017-12-01

With the copious amount of science and pseudoscience reported on by non-experts in the media, it is critical for educators to help students develop into scientifically literate citizens. One of the most direct ways to help students develop deep scientific understanding and the skills to critically question the information they encounter is to bring science into their daily experiences and to contextualize scientific inquiry within the classroom. Our work aims to use a systems-based models approach to engage students in science, in both formal and informal contexts. Using the Understanding Global Change (UGC) and the Understanding Science models developed at the Museum of Paleontology at UC Berkeley, high school students from Arizona were tasked with developing a viable citizen science program for use at the Center for Alaskan Coastal Studies in Homer, Alaska. Experts used the UGC model to help students define why they were doing the work, and give context to the importance of citizen science. Empowered with an understanding of the scientific process, excited by the purpose of their work and how it could contribute to the scientific community, students whole-heartedly worked together to develop intertidal monitoring protocols for two locations while staying at Peterson Bay Field Station, Homer. Students, instructors, and scientists used system models to communicate and discuss their understanding of the biological, physical, and chemical processes in Kachemak Bay. This systems-based models approach is also being used in an integrative high school physics, chemistry, and biology curriculum in a truly unprecedented manner. Using the Understanding Global Change framework to organize curriculum scope and sequence, the course addresses how the earth systems work, how interdisciplinary science knowledge is necessary to understand those systems, and how scientists and students can measure changes within those systems.

Understanding the Cray X1 System

NASA Technical Reports Server (NTRS)

Cheung, Samson

2004-01-01

This paper helps the reader understand the characteristics of the Cray X1 vector supercomputer system, and provides hints and information to enable the reader to port codes to the system. It provides a comparison between the basic performance of the X1 platform and other platforms that are available at NASA Ames Research Center. A set of codes, solving the Laplacian equation with different parallel paradigms, is used to understand some features of the X1 compiler. An example code from the NAS Parallel Benchmarks is used to demonstrate performance optimization on the X1 platform.

The busy social brain: evidence for automaticity and control in the neural systems supporting social cognition and action understanding.

PubMed

Spunt, Robert P; Lieberman, Matthew D

2013-01-01

Much social-cognitive processing is believed to occur automatically; however, the relative automaticity of the brain systems underlying social cognition remains largely undetermined. We used functional MRI to test for automaticity in the functioning of two brain systems that research has indicated are important for understanding other people's behavior: the mirror neuron system and the mentalizing system. Participants remembered either easy phone numbers (low cognitive load) or difficult phone numbers (high cognitive load) while observing actions after adopting one of four comprehension goals. For all four goals, mirror neuron system activation showed relatively little evidence of modulation by load; in contrast, the association of mentalizing system activation with the goal of inferring the actor's mental state was extinguished by increased cognitive load. These results support a dual-process model of the brain systems underlying action understanding and social cognition; the mirror neuron system supports automatic behavior identification, and the mentalizing system supports controlled social causal attribution.

Heliophysics 2009 Roadmap and Global Change: Possibilities for Improved Understanding of the Connection

NASA Technical Reports Server (NTRS)

Spann, Jim

2010-01-01

Heliophysics is the science that includes all aspects of the research needed to understand the Sun and its effects on the Earth and the solar system. Six science targets: 1. Origins of Near-Earth Plasma - to understand the origin and transport of terrestrial plasma from its source to the magnetosphere and solar wind. 2. Solar Energetic Particle Acceleration and Transport - to understand how and where solar eruptions accelerate energetic particles that reach Earth. 3. Ion-Neutral Coupling in the Atmosphere - to understand how neutral winds control ionospheric variability. 4. Climate Impacts of Space Radiation - to understand our atmosphere s response to auroral, radiation belt, and solar energetic particles, and the associated effects on nitric oxide (NO) and ozone. 5. Dynamic Geospace Coupling - to understand how magnetospheric dynamics provides energy into the coupled ionosphere-magnetosphere system. 6. Heliospheric Magnetics - to understand the flow and dynamics of transient magnetic structures form the solar interior to Earth.

Comparing Virtual and Physical Robotics Environments for Supporting Complex Systems and Computational Thinking

ERIC Educational Resources Information Center

Berland, Matthew; Wilensky, Uri

2015-01-01

Both complex systems methods (such as agent-based modeling) and computational methods (such as programming) provide powerful ways for students to understand new phenomena. To understand how to effectively teach complex systems and computational content to younger students, we conducted a study in four urban middle school classrooms comparing…

Learning and Understanding System Stability Using Illustrative Dynamic Texture Examples

ERIC Educational Resources Information Center

Liu, Huaping; Xiao, Wei; Zhao, Hongyan; Sun, Fuchun

2014-01-01

System stability is a basic concept in courses on dynamic system analysis and control for undergraduate students with computer science backgrounds. Typically, this was taught using a simple simulation example of an inverted pendulum. Unfortunately, many difficult issues arise in the learning and understanding of the concepts of stability,…

You and the System: An Alternative to Revolution.

ERIC Educational Resources Information Center

Rodeck, Mrs. Willard; And Others

This curriculum guide for secondary grades encourages new young voters to understand and participate in the political system. A major objective is to help students consider the political system as an agent of change, and, moreover, to help them understand how individuals control, influence, and change government. Students learn that there are many…

Calculator Logic Systems and Mathematical Understandings.

ERIC Educational Resources Information Center

Burrows, Enid R.

This monograph is aimed at helping the reader understand the built-in logic of various calculator operating systems. It is an outgrowth of workshop contacts with in-service and pre-service teachers of mathematics and is in response to their request for a book on the subject of calculator logic systems and calculator algorithms. The mathematical…

Develop a Systems Approach to Characterizing and Predicting Thyroid Toxicity using an Amphibian Model

EPA Science Inventory

This research makes use of in vitro and in vivo approaches to understand and discriminate the compensatory and toxicological responses of the highly regulated HPT system. Development of an initial systems model will be based on the current understanding of the HPT axis and the co...

The Effect of Conceptual Diagrams on Aviation Mechanics' Technical Systems Understanding.

ERIC Educational Resources Information Center

Satchwell, Richard E.; Johnson, Scott D.

A quasi-experimental study explored the effect of functional flow diagrams on technical system understanding. An individualized field training package which contained schematic diagrams that illustrated an aircraft's electrical system was complimented with functional flow diagrams. In a 4-week treatment, a control group of 10 students enrolled in…

On the role of patterns in understanding the functioning of soil-vegetation-atmosphere systems

USDA-ARS?s Scientific Manuscript database

In this paper, we review the role of patterns to improve our understanding of water, mass and energy exchange processes in soil-vegetation-atmosphere systems. We explore the main mechanisms that lead to the formation of patterns in these systems and discuss different approaches to characterizing and...

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXI, I--MAINTAINING THE AIR SYSTEM--CATERPILLAR DIESEL ENGINE, II--UNDERSTANDING REAR END SUSPENSION.

ERIC Educational Resources Information Center

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE AIR SYSTEM AND REAR AXLE SUSPENSION USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) AIR INDUCTION AND EXHAUST SYSTEM, (2) VALVE MECHANISM, (3) TROUBLESHOOTING THE AIR SYSTEM, (4) PURPOSE OF VEHICLE SUSPENSION, (5) TANDEM…

The Nested Systems of Local School Development: Understanding Improved Interaction and Capacities in the Different Sub-Systems of Schools

ERIC Educational Resources Information Center

Adolfsson, Carl-Henrik; Alvunger, Daniel

2017-01-01

In school systems around the world, there is an increasing focus on students' academic achievement. The challenge of how to improve schools is an important issue for all levels in the school system. However, a central question of both practical and theoretical relevance is how it is possible to understand why (or why not) school-development…

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXII, I--MAINTAINING THE FUEL SYSTEM (PART I)--CUMMINS DIESEL ENGINE, II--UNDERSTANDING THE DIFFERENTIAL.

ERIC Educational Resources Information Center

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE FUNCTION AND MAINTENANCE OF THE DIESEL ENGINE FUEL SYSTEM AND DIFFERENTIAL DRIVE UNITS USED IN DIESEL POWERED VEHICLES. TOPICS ARE (1) FUEL SYSTEM COMPARISONS, (2) FUEL SYSTEM SUPPLY COMPONENTS, (3) FUEL SUPPLY SECTION MAINTENANCE, (4) FUNCTION OF THE DIFFERENTIAL,…

Dissecting innate immune responses with the tools of systems biology.

PubMed

Smith, Kelly D; Bolouri, Hamid

2005-02-01

Systems biology strives to derive accurate predictive descriptions of complex systems such as innate immunity. The innate immune system is essential for host defense, yet the resulting inflammatory response must be tightly regulated. Current understanding indicates that this system is controlled by complex regulatory networks, which maintain homoeostasis while accurately distinguishing pathogenic infections from harmless exposures. Recent studies have used high throughput technologies and computational techniques that presage predictive models and will be the foundation of a systems level understanding of innate immunity.

Mountain hydrology of the western United States

USGS Publications Warehouse

Bales, Roger C.; Molotch, Noah P.; Painter, Thomas H; Dettinger, Michael D.; Rice, Robert; Dozier, Jeff

2006-01-01

Climate change and climate variability, population growth, and land use change drive the need for new hydrologic knowledge and understanding. In the mountainous West and other similar areas worldwide, three pressing hydrologic needs stand out: first, to better understand the processes controlling the partitioning of energy and water fluxes within and out from these systems; second, to better understand feedbacks between hydrological fluxes and biogeochemical and ecological processes; and, third, to enhance our physical and empirical understanding with integrated measurement strategies and information systems. We envision an integrative approach to monitoring, modeling, and sensing the mountain environment that will improve understanding and prediction of hydrologic fluxes and processes. Here extensive monitoring of energy fluxes and hydrologic states are needed to supplement existing measurements, which are largely limited to streamflow and snow water equivalent. Ground‐based observing systems must be explicitly designed for integration with remotely sensed data and for scaling up to basins and whole ranges.

Disbonding effects on elastic wave generation and reception by bonded piezoelectric sensor systems

NASA Astrophysics Data System (ADS)

Blackshire, James L.; Martin, Steven A.; Na, Jeong K.

2007-04-01

Durable integrated sensor systems are needed for long-term health monitoring evaluations of aerospace systems. For legacy aircraft the primary means of implementing a sensor system will be through surface mounting or bonding of the sensors to the structure. Previous work has shown that the performance of surface-bonded piezo sensors can degrade due to environmental effects such as vibrations, temperature fluctuations, and substrate flexure motions. This performance degradation included sensor cracking, disbonding, and general loss of efficiency over time. In this research effort, the bonding state of a piezo sensor system was systematically studied to understand and improve the long-term durability and survivability of the sensor system. Analytic and computational models were developed and used to understand elastic wave generation and reception performance for various states of sensor disbond. Experimental studies were also conducted using scanning laser vibrometry, pitch-catch ultrasound, and pulse-echo ultrasound methods to understand elastic wave propagation effects in thin plate materials. Significant performance loss was observed for increasing levels of sensor disbond as well as characteristic frequency signatures which may be useful in understanding sensor performance levels for future structural health monitoring systems.

Environmental stressors influencing hormones and systems physiology in cattle

PubMed Central

2014-01-01

Environmental stressors undoubtedly influence organismal biology, specifically the endocrine system that, in turn, impact cattle at the systems physiology level. Despite the significant advances in understanding the genetic determinants of the ideal dairy or beef cow, there is a grave lack of understanding of the systems physiology and effects of the environmental stressors that interfere with the endocrine system. This is a major problem because the lack of such knowledge is preventing advances in understanding gene-environment interactions and developing science-based solutions to these challenges. In this review, we synthesize the current knowledge on the nature of the major environmental stressors, such as climate (heat, cold, wind, and humidity), nutrition (feeds, feeding systems, and endocrine disruptors) and management (housing density and conditions, transportation, weaning practices). We summarize the impact of each one of these factors on cattle at the systems level, and provide solutions for the challenges. PMID:24996419

Management of Water Quality Data Within the Corps of Engineers, 1979.

DTIC Science & Technology

1980-12-01

integrated data base systems have been in the business area. SIR was developed for scientific researchers. 3. An evaluation of the system is as follows. a...of the UPGRADE system. 3. An evaluation of the system is as follows. a. Advanatges : (1) Anyone who understands the data and principles of anal- ysis...A BASIC UNDERSTANDING OF THE STRUCTURE OF THE UPGRADE SYSTEM START SINRTCOMPUTER ECET IE.ECUTE UPGRADE IA IDN IFY ERINAL TYPE SELECTION OF OPERATIONAL

A history of the autonomic nervous system: part II: from Reil to the modern era.

PubMed

Oakes, Peter C; Fisahn, Christian; Iwanaga, Joe; DiLorenzo, Daniel; Oskouian, Rod J; Tubbs, R Shane

2016-12-01

The history of the study of the autonomic nervous system is rich. At the beginning of the nineteenth century, scientists were beginning to more firmly grasp the reality of this part of the human nervous system. The evolution of our understanding of the autonomic nervous system has a rich history. Our current understanding is based on centuries of research and trial and error.

How Systems Engineering and Risk Management Defend Against Murphy's Law and Human Error

NASA Technical Reports Server (NTRS)

Bay, Michael; Connley, Warren

2004-01-01

Systems Engineering and Risk Management processes can work synergistically to defend against the causes of many mission ending failures. Defending against mission ending failures is facilitated by fostering a team that has a healthy respect for Murphy's Law and a team with a of curiosity for how things work, how they can fail, and what they need to know. This curiosity is channeled into making the unknowns known or what is uncertain more certain. Efforts to assure mission success require the expenditure of energy in the following areas: 1. Understanding what defines Mission Success as guided by the customer's needs, objectives and constraints. 2. Understanding how the system is supposed to work and how the system is to be produced, fueled by the curiosity of how the system should work and how it should be produced. 3. Understanding how the system can fail and how the system might not be produced on time and within cost, fueled by the curiosity of how the system might fail and how production might be difficult. 4. Understanding what we need to know and what we need learn for proper completion of the above three items, fueled by the curiosity of what we might not know in order to make the best decisions.

Directly Comparing Computer and Human Performance in Language Understanding and Visual Reasoning.

ERIC Educational Resources Information Center

Baker, Eva L.; And Others

Evaluation models are being developed for assessing artificial intelligence (AI) systems in terms of similar performance by groups of people. Natural language understanding and vision systems are the areas of concentration. In simplest terms, the goal is to norm a given natural language system's performance on a sample of people. The specific…

Studies Of Vibrations In Gearboxes

NASA Technical Reports Server (NTRS)

Choy, Fred K.; Ruan, Yeefeng F.; Tu, Yu K.; Zakrajsek, James J.; Oswald, Fred B.; Coy, John J.; Townsend, Dennis P.

1994-01-01

Three NASA technical memorandums summarize studies of vibrations in gearboxes. Directed toward understanding and reducing gearbox noise caused by coupling of vibrations from meshing gears, through gear shafts and their bearings, to surfaces of gearbox housings. Practical systems in which understanding and reduction of gearbox noise beneficial include helicopter, car, and truck transmissions; stationary geared systems; and gear-driven actuator systems.

What Influences Geography Teachers' Usage of Geographic Information Systems? A Structural Equation Analysis

ERIC Educational Resources Information Center

Lay, Jinn-Guey; Chi, Yu-Lin; Hsieh, Yeu-Sheng; Chen, Yu-Wen

2013-01-01

Understanding the usage of the geographic information system (GIS) among geography teachers is a crucial step in evaluating the current dissemination of GIS knowledge and skills in Taiwan's educational system. The primary contribution of this research is to further our understanding of the factors that affect teachers' GIS usage. The structural…

What Is the Value of @*#? Deepening Teachers' Understanding of Place Value

ERIC Educational Resources Information Center

Hopkins, Theresa M.; Cady, Jo Ann

2007-01-01

This article reports on the use of a unique number system to facilitate teachers' understanding of the concepts of place value. Teachers' mastery of base-ten may hinder their recognition of the difficulties students have with place value, so the authors created a number system that used five symbols to represent values. Using this system, teachers…

Collaborative Modelling of the Vascular System--Designing and Evaluating a New Learning Method for Secondary Students

ERIC Educational Resources Information Center

Haugwitz, Marion; Sandmann, Angela

2010-01-01

Understanding biological structures and functions is often difficult because of their complexity and micro-structure. For example, the vascular system is a complex and only partly visible system. Constructing models to better understand biological functions is seen as a suitable learning method. Models function as simplified versions of real…

Systems Integration Challenges for a National Space Launch System

NASA Technical Reports Server (NTRS)

May, Todd A.

2011-01-01

System Integration was refined through the complexity and early failures experienced in rocket flight. System Integration encompasses many different viewpoints of the system development. System Integration must ensure consistency in development and operations activities. Human Space Flight tends toward large, complex systems. Understanding the system fs operational and use context is the guiding principle for System Integration: (1) Sizeable costs can be driven into systems by not fully understanding context (2). Adhering to the system context throughout the system fs life cycle is essential to maintaining efficient System Integration. System Integration exists within the System Architecture. Beautiful systems are simple in use and operation -- Block upgrades facilitate manageable steps in functionality evolution. Effective System Integration requires a stable system concept. Communication is essential to system simplicity

Learning the organization: a model for health system analysis for new nurse administrators.

PubMed

Clark, Mary Jo

2004-01-01

Health systems are large and complex organizations in which multiple components and processes influence system outcomes. In order to effectively position themselves in such organizations, nurse administrators new to a system must gain a rapid understanding of overall system operation. Such understanding is facilitated by use of a model for system analysis. The model presented here examines the dynamic interrelationships between and among internal and external elements as they affect system performance. External elements to be analyzed include environmental factors and characteristics of system clientele. Internal elements flow from the mission and goals of the system and include system culture, services, resources, and outcomes.

Knowledge, Understanding, and Behavior

DTIC Science & Technology

2003-10-04

UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP021346 TITLE: Knowledge , Understanding , and Behavior DISTRIBUTION... Knowledge , Understanding , and Behavior James Albus Intelligent Systems Division , National Institute of Standards and Technology, Gaithersburg, MD 20899 301... understanding ? How does understanding the world works, and knowledge of procedures for using influence behavior? These are philosophical questions models to

Information-Theoretic Approach May Shed a Light to a Better Understanding and Sustaining the Integrity of Ecological-Societal Systems under Changing Climate

NASA Astrophysics Data System (ADS)

Kim, J.

2016-12-01

Considering high levels of uncertainty, epistemological conflicts over facts and values, and a sense of urgency, normal paradigm-driven science will be insufficient to mobilize people and nation toward sustainability. The conceptual framework to bridge the societal system dynamics with that of natural ecosystems in which humanity operates remains deficient. The key to understanding their coevolution is to understand `self-organization.' Information-theoretic approach may shed a light to provide a potential framework which enables not only to bridge human and nature but also to generate useful knowledge for understanding and sustaining the integrity of ecological-societal systems. How can information theory help understand the interface between ecological systems and social systems? How to delineate self-organizing processes and ensure them to fulfil sustainability? How to evaluate the flow of information from data through models to decision-makers? These are the core questions posed by sustainability science in which visioneering (i.e., the engineering of vision) is an essential framework. Yet, visioneering has neither quantitative measure nor information theoretic framework to work with and teach. This presentation is an attempt to accommodate the framework of self-organizing hierarchical open systems with visioneering into a common information-theoretic framework. A case study is presented with the UN/FAO's communal vision of climate-smart agriculture (CSA) which pursues a trilemma of efficiency, mitigation, and resilience. Challenges of delineating and facilitating self-organizing systems are discussed using transdisciplinary toold such as complex systems thinking, dynamic process network analysis and multi-agent systems modeling. Acknowledgments: This study was supported by the Korea Meteorological Administration Research and Development Program under Grant KMA-2012-0001-A (WISE project).

Using Functional Flow Diagrams to Enhance Technical Systems Understanding.

ERIC Educational Resources Information Center

Satchwell, Richard E.

1997-01-01

A treatment group of 20 aviation students used training manuals that presented functional flow diagrams before schematic diagrams. Comparison of data from 10 controls on a card-sort task showed that functional flow diagrams enhanced understanding of technical systems. (SK)

Therapy for Childhood Sexual Abuse Survivors using Attachment and Family Systems Theory Orientations.

PubMed

Karakurt, Gunnur; Silver, Kristin E

2014-01-01

The aim of this paper is to understand the effects of childhood sexual abuse on a survivor's later life. For understanding and treating the emotional distress and interpersonal problems resulting from childhood sexual abuse, attachment theory provides a valuable framework. When this framework is combined with family systems theory, it can help therapists understand the family context where sexual abuse occurs and how this affects health and functioning throughout the lifespan. Case examples of female adult sexual abuse survivors are also explored, with insight from the intersection of systems and attachment theories.

The MIT Summit Speech Recognition System: A Progress Report

DTIC Science & Technology

1989-01-01

understanding of the human communication process. Despite recent development of some speech recognition systems with high accuracy, the performance of such...over the past four decades on human communication , in the hope that such systems will one day have a performance approaching that of humans. We are...optimize its use. Third, the system must have a stochastic component to deal with the present state of ignorance in our understanding of the human

[The ontogeny of the mirror neuron system].

PubMed

Myowa-Yamakoshi, Masako

2014-06-01

Abstract Humans utilize the mirror neuron system to understand and predict others' actions. However, the ontogeny of the mirror neuron system remains unknown. Whether mirror neuron function is an innate trait or whether mirror neurons acquire their sensorimotor matching properties ontogenetically remains to be clarified. In this paper, I review the ontogenetic theory of the mirror neuron system. I then discuss the functioning of the mirror neuron system in the context of social cognitive abilities, which are unique to humans. Recently, some researchers argue that it is too early to interpret the function of mirror neurons as an understanding of the underlying psychological states of others. They imply that such functioning would require inferential cognitive processes that are known to involve areas outside the mirror neuron system. Filling in this missing link may be the key to elucidating the unique ability of humans to understand others' actions.

Molecular microenvironments: Solvent interactions with nucleic acid bases and ions

NASA Technical Reports Server (NTRS)

Macelroy, R. D.; Pohorille, A.

1986-01-01

The possibility of reconstructing plausible sequences of events in prebiotic molecular evolution is limited by the lack of fossil remains. However, with hindsight, one goal of molecular evolution was obvious: the development of molecular systems that became constituents of living systems. By understanding the interactions among molecules that are likely to have been present in the prebiotic environment, and that could have served as components in protobiotic molecular systems, plausible evolutionary sequences can be suggested. When stable aggregations of molecules form, a net decrease in free energy is observed in the system. Such changes occur when solvent molecules interact among themselves, as well as when they interact with organic species. A significant decrease in free energy, in systems of solvent and organic molecules, is due to entropy changes in the solvent. Entropy-driven interactioins played a major role in the organization of prebiotic systems, and understanding the energetics of them is essential to understanding molecular evolution.

Family Systems Training for Medical Students.

PubMed

Thabrew, Hiran

2018-05-01

To evaluate whether a workshop on family systems delivered to medical students could improve participants' understanding of families from a systemic point of view and help them recognise and address systemic issues that may be affecting their patients. Fifth year (senior) medical students ( n = 36) from the University of Auckland participated in a 90-min workshop about family systems. Pre- and post-workshop, self-reported measures of knowledge and confidence were completed and qualitative feedback was also obtained from participants. The workshop was well received and its interactive and role-play based nature were particularly appreciated. Participants reported gains in all explored areas of knowledge and understanding, suggesting that the workshop met its desired aims. This workshop is an educationally effective and expedient way to equip medical students with some knowledge and understanding about family systems. It may benefit their future work with individual patients and families.

Structural Complexity in Linguistic Systems Research Topic 3: Mathematical Sciences

DTIC Science & Technology

2015-04-01

understanding of structure (pattern, correlation, memory , semantics , ...) observed in linguistic systems and process? On this score we believe the...on our understanding of structure (pattern, correlation, memory , semantics , ...) observed in linguistic systems and process? On this score we believe...promised to overcome these difficulties, since it gives a clear and constructive view of structure in memoryful stochastic processes. In principle, this

The Use of Complex Adaptive Systems as a Generative Metaphor in an Action Research Study of an Organisation

ERIC Educational Resources Information Center

Brown, Callum

2008-01-01

Understanding the dynamic behaviour of organisations is challenging and this study uses a model of complex adaptive systems as a generative metaphor to address this challenge. The research question addressed is: How might a conceptual model of complex adaptive systems be used to assist in understanding the dynamic nature of organisations? Using an…

Predictors of Interpersonal Trust in Virtual Distributed Teams

DTIC Science & Technology

2008-09-01

understand systems that are very complex in nature . Such understanding is essential to facilitate building or maintaining operators’ mental models of the...a significant impact on overall system performance. Specifically, the level of automation that combined human generation of options with computer...and/or computer servers had a significant impact on automated system performance. Additionally, Parasuraman, Sheridan, & Wickens (2000) proposed

Evaluating a Bilingual Text-Mining System with a Taxonomy of Key Words and Hierarchical Visualization for Understanding Learner-Generated Text

ERIC Educational Resources Information Center

Kong, Siu Cheung; Li, Ping; Song, Yanjie

2018-01-01

This study evaluated a bilingual text-mining system, which incorporated a bilingual taxonomy of key words and provided hierarchical visualization, for understanding learner-generated text in the learning management systems through automatic identification and counting of matching key words. A class of 27 in-service teachers studied a course…

Supporting Indigenous Students' Understanding of the Numeration System of Their First Language

ERIC Educational Resources Information Center

Cortina, Jose Luis

2013-01-01

Results from a project conducted in Mexico are discussed, in which a group of 17 indigenous teachers analyzed the numeration systems of their first language. The main goal of the project is to develop resources that help teachers in supporting students' understanding of the systems. In the first phase of the project, the central organizing ideas…

Understanding the Barriers to College Access for Former Foster Youth at the Los Angeles Community College District

ERIC Educational Resources Information Center

Sousa, John Chaves

2013-01-01

Generally referred to as aged-out youth, approximately 20,000 former foster youth leave foster care each year, with very few enrolling into the community college system. Many enroll into a college system without a clear understanding of the system. Unable to maneuver, most former foster youth will drop out. The current exploratory, comparative…

How Pre-Service Teachers Navigate Trade-Offs of Food Systems across Time Scales: A Lens for Exploring Understandings of Sustainability

ERIC Educational Resources Information Center

Yamashita, Lina; Hayes, Kathryn; Trexler, Cary J.

2017-01-01

In response to the increasing recognition of the need for sustainable food systems, research on students' and educators' knowledge of food systems and sustainability more broadly has grown but has generally focused on what people "fail" to understand. Moving away from this deficit approach, the present study used semi-structured…

The spatiotemporal system dynamics of acquired resistance in an engineered microecology.

PubMed

Datla, Udaya Sree; Mather, William H; Chen, Sheng; Shoultz, Isaac W; Täuber, Uwe C; Jones, Caroline N; Butzin, Nicholas C

2017-11-22

Great strides have been made in the understanding of complex networks; however, our understanding of natural microecologies is limited. Modelling of complex natural ecological systems has allowed for new findings, but these models typically ignore the constant evolution of species. Due to the complexity of natural systems, unanticipated interactions may lead to erroneous conclusions concerning the role of specific molecular components. To address this, we use a synthetic system to understand the spatiotemporal dynamics of growth and to study acquired resistance in vivo. Our system differs from earlier synthetic systems in that it focuses on the evolution of a microecology from a killer-prey relationship to coexistence using two different non-motile Escherichia coli strains. Using empirical data, we developed the first ecological model emphasising the concept of the constant evolution of species, where the survival of the prey species is dependent on location (distance from the killer) or the evolution of resistance. Our simple model, when expanded to complex microecological association studies under varied spatial and nutrient backgrounds may help to understand the complex relationships between multiple species in intricate natural ecological networks. This type of microecological study has become increasingly important, especially with the emergence of antibiotic-resistant pathogens.

Mathematical modeling of physiological systems: an essential tool for discovery.

PubMed

Glynn, Patric; Unudurthi, Sathya D; Hund, Thomas J

2014-08-28

Mathematical models are invaluable tools for understanding the relationships between components of a complex system. In the biological context, mathematical models help us understand the complex web of interrelations between various components (DNA, proteins, enzymes, signaling molecules etc.) in a biological system, gain better understanding of the system as a whole, and in turn predict its behavior in an altered state (e.g. disease). Mathematical modeling has enhanced our understanding of multiple complex biological processes like enzyme kinetics, metabolic networks, signal transduction pathways, gene regulatory networks, and electrophysiology. With recent advances in high throughput data generation methods, computational techniques and mathematical modeling have become even more central to the study of biological systems. In this review, we provide a brief history and highlight some of the important applications of modeling in biological systems with an emphasis on the study of excitable cells. We conclude with a discussion about opportunities and challenges for mathematical modeling going forward. In a larger sense, the review is designed to help answer a simple but important question that theoreticians frequently face from interested but skeptical colleagues on the experimental side: "What is the value of a model?" Copyright © 2014 Elsevier Inc. All rights reserved.

Modelling ecological systems in a changing world

PubMed Central

Evans, Matthew R.

2012-01-01

The world is changing at an unprecedented rate. In such a situation, we need to understand the nature of the change and to make predictions about the way in which it might affect systems of interest; often we may also wish to understand what might be done to mitigate the predicted effects. In ecology, we usually make such predictions (or forecasts) by making use of mathematical models that describe the system and projecting them into the future, under changed conditions. Approaches emphasizing the desirability of simple models with analytical tractability and those that use assumed causal relationships derived statistically from data currently dominate ecological modelling. Although such models are excellent at describing the way in which a system has behaved, they are poor at predicting its future state, especially in novel conditions. In order to address questions about the impact of environmental change, and to understand what, if any, action might be taken to ameliorate it, ecologists need to develop the ability to project models into novel, future conditions. This will require the development of models based on understanding the processes that result in a system behaving the way it does, rather than relying on a description of the system, as a whole, remaining valid indefinitely. PMID:22144381

Climate change: Cropping system changes and adaptations

USDA-ARS?s Scientific Manuscript database

Climate change impacts the life of every person; however, there is little comprehensive understanding of the direct and indirect effects of climate change on agriculture. Since our food, feed, fiber, and fruit is derived from agricultural systems, understanding the effects of changing temperature, p...

What is New in Understanding how the Whole Works

NASA Astrophysics Data System (ADS)

San Miguel, Maxi

Cybernetics, systems science, synergetics, global systems, complexity - what is new in understanding how the whole works? There are two new opportunities that pose at least two challenges: the availability of massive data and the direct social relevance of the field of research...

The Immune System: Basis of so much Health and Disease: 2. Innate Immunity.

PubMed

Scully, Crispian; Georgakopoulou, Eleni A; Hassona, Yazan

2017-03-01

The immune system is the body’s primary defence mechanism against infections, and disturbances in the system can cause disease if the system fails in defence functions (in immunocompromised people), or if the activity is detrimental to the host (as in auto-immune and auto-inflammatory states). A healthy immune system is also essential to normal health of dental and oral tissues. This series presents the basics for the understanding of the immune system, this article covering innate immunity. Clinical relevance: Modern dental clinicians need a basic understanding of the immune system as it underlies health and disease.

The Immune System: Basis of so much Health and Disease: 3. Adaptive Immunity.

PubMed

Scully, Crispian; Georgakopoulou, Eleni A; Hassona, Yazan

2017-04-01

The immune system is the body’s primary defence mechanism against infections, and disturbances in the system can cause disease if the system fails in defence functions (in immunocompromised people), or if the activity is detrimental to the host (as in auto-immune and auto-inflammatory states). A healthy immune system is also essential to normal health of dental and oral tissues. This series presents the basics for the understanding of the immune system; this article covers adaptive immunity. Clinical relevance: Dental clinicians need a basic understanding of the immune system as it underlies health and disease.

Podium: Ranking Data Using Mixed-Initiative Visual Analytics.

PubMed

Wall, Emily; Das, Subhajit; Chawla, Ravish; Kalidindi, Bharath; Brown, Eli T; Endert, Alex

2018-01-01

People often rank and order data points as a vital part of making decisions. Multi-attribute ranking systems are a common tool used to make these data-driven decisions. Such systems often take the form of a table-based visualization in which users assign weights to the attributes representing the quantifiable importance of each attribute to a decision, which the system then uses to compute a ranking of the data. However, these systems assume that users are able to quantify their conceptual understanding of how important particular attributes are to a decision. This is not always easy or even possible for users to do. Rather, people often have a more holistic understanding of the data. They form opinions that data point A is better than data point B but do not necessarily know which attributes are important. To address these challenges, we present a visual analytic application to help people rank multi-variate data points. We developed a prototype system, Podium, that allows users to drag rows in the table to rank order data points based on their perception of the relative value of the data. Podium then infers a weighting model using Ranking SVM that satisfies the user's data preferences as closely as possible. Whereas past systems help users understand the relationships between data points based on changes to attribute weights, our approach helps users to understand the attributes that might inform their understanding of the data. We present two usage scenarios to describe some of the potential uses of our proposed technique: (1) understanding which attributes contribute to a user's subjective preferences for data, and (2) deconstructing attributes of importance for existing rankings. Our proposed approach makes powerful machine learning techniques more usable to those who may not have expertise in these areas.

Understanding multinational companies in public health systems, using a competitive advantage framework.

PubMed

Lethbridge, Jane

2011-07-01

This paper discusses the findings of a study which developed five case studies of five multinational health care companies involved in public health care systems. Strategies were analysed in terms of attitude to marketing, pricing and regulation. The company strategies have been subjected to an analysis using Porter's Five Forces, a business strategy framework, which is unusual in health policy studies. This paper shows how analysing company strategy using a business tool can contribute to understanding the strategies of global capital in national health systems. It shows how social science methodologies can draw from business methods to explain company strategies. The five companies considered in this paper demonstrate that their strategies have many dimensions, which fit into Porter's Five Forces of comparative advantage. More importantly the Five Forces can be used to identify factors that influence company entry into public health care systems. The process of examining the strategic objectives of five health care companies shows that a business tool can help to explain the actions and motives of health care companies towards public health care systems, and so contribute to a better understanding of the strategies of global capital in national health systems. Health service commissioners need to understand this dynamic process, which will evolve as the nature of public health care systems change.

20 CFR 662.300 - What is the Memorandum of Understanding (MOU)?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false What is the Memorandum of Understanding (MOU... Understanding for the One-Stop Delivery System § 662.300 What is the Memorandum of Understanding (MOU)? (a) The Memorandum of Understanding (MOU) is an agreement developed and executed between the Local Board, with the...

Science-Based, Community-Driven Approach to Reducing Glacier Lake Outburst Flood Risks in the Nepal Himalaya

NASA Astrophysics Data System (ADS)

Rounce, D.; McKinney, D. C.; Byers, A. C.; Shrestha, M. K.; Cuellar, A. D.; Sherpa, S. F.

2016-12-01

Over the past several decades, hundreds of lower altitude Himalayan glaciers have been melting, leaving behind new glacier lakes, holding millions of cubic meters of water. Usually contained by dams of loose boulders and soil, these lakes present a risk of glacial lake outburst floods (GLOFs). These glacial-dominated areas pose unique challenges to downstream communities in adapting to global climate change, particularly in terms of increasing threats of GLOFs. This interdisciplinary research captures unique knowledge of the Himalayan region and contributes to the development of a new generation of scientists in the area of coupled natural and human systems of glacier-dominated mountain systems. The goals of the research are to: (1) Understand natural system dynamics through an analysis of the impacts of climate change on glacial lakes, (2) Understand the human system dynamics through the strengthening of community resiliency to glacial lake hazards by developing community-driven glacial lake risk reduction systems, (3) Understand how the natural system affects the human system through the assessment of local ecological knowledge and understanding of hydrological resources and the vulnerability of the social-ecological system to GLOF hazard, and (4) Understand how the human system affects the natural system through the design and modeling of community-driven solutions to analyze the reduction of flood risk and the evolution of glacial lakes. The project integrates in situ physical and societal observations with geospatial analyses, intensive glacial hydrology and outburst flood modeling, key respondents' interviews, and community level mappings and focus groups. The Imja glacial lake in the Khumbu region of Nepal is the field research site. The project is assessing outburst flood-related processes that include glacier hydrology, river flow, hydraulics, and sediment/debris transport models. These natural system impacts are being integrated with the human science aspects to evaluate socio-economic impacts of potential outburst flood events on communities, households, and ecotourism.

A review of human factors challenges of complex adaptive systems: discovering and understanding chaos in human performance.

PubMed

Karwowski, Waldemar

2012-12-01

In this paper, the author explores a need for a greater understanding of the true nature of human-system interactions from the perspective of the theory of complex adaptive systems, including the essence of complexity, emergent properties of system behavior, nonlinear systems dynamics, and deterministic chaos. Human performance, more often than not, constitutes complex adaptive phenomena with emergent properties that exhibit nonlinear dynamical (chaotic) behaviors. The complexity challenges in the design and management of contemporary work systems, including service systems, are explored. Examples of selected applications of the concepts of nonlinear dynamics to the study of human physical performance are provided. Understanding and applications of the concepts of theory of complex adaptive and dynamical systems should significantly improve the effectiveness of human-centered design efforts of a large system of systems. Performance of many contemporary work systems and environments may be sensitive to the initial conditions and may exhibit dynamic nonlinear properties and chaotic system behaviors. Human-centered design of emergent human-system interactions requires application of the theories of nonlinear dynamics and complex adaptive system. The success of future human-systems integration efforts requires the fusion of paradigms, knowledge, design principles, and methodologies of human factors and ergonomics with those of the science of complex adaptive systems as well as modern systems engineering.

Automated speech understanding: the next generation

NASA Astrophysics Data System (ADS)

Picone, J.; Ebel, W. J.; Deshmukh, N.

1995-04-01

Modern speech understanding systems merge interdisciplinary technologies from Signal Processing, Pattern Recognition, Natural Language, and Linguistics into a unified statistical framework. These systems, which have applications in a wide range of signal processing problems, represent a revolution in Digital Signal Processing (DSP). Once a field dominated by vector-oriented processors and linear algebra-based mathematics, the current generation of DSP-based systems rely on sophisticated statistical models implemented using a complex software paradigm. Such systems are now capable of understanding continuous speech input for vocabularies of several thousand words in operational environments. The current generation of deployed systems, based on small vocabularies of isolated words, will soon be replaced by a new technology offering natural language access to vast information resources such as the Internet, and provide completely automated voice interfaces for mundane tasks such as travel planning and directory assistance.

Supporting second grade lower secondary school students’ understanding of linear equation system in two variables using ethnomathematics

NASA Astrophysics Data System (ADS)

Nursyahidah, F.; Saputro, B. A.; Rubowo, M. R.

2018-03-01

The aim of this research is to know the students’ understanding of linear equation system in two variables using Ethnomathematics and to acquire learning trajectory of linear equation system in two variables for the second grade of lower secondary school students. This research used methodology of design research that consists of three phases, there are preliminary design, teaching experiment, and retrospective analysis. Subject of this study is 28 second grade students of Sekolah Menengah Pertama (SMP) 37 Semarang. The result of this research shows that the students’ understanding in linear equation system in two variables can be stimulated by using Ethnomathematics in selling buying tradition in Peterongan traditional market in Central Java as a context. All of strategies and model that was applied by students and also their result discussion shows how construction and contribution of students can help them to understand concept of linear equation system in two variables. All the activities that were done by students produce learning trajectory to gain the goal of learning. Each steps of learning trajectory of students have an important role in understanding the concept from informal to the formal level. Learning trajectory using Ethnomathematics that is produced consist of watching video of selling buying activity in Peterongan traditional market to construct linear equation in two variables, determine the solution of linear equation in two variables, construct model of linear equation system in two variables from contextual problem, and solving a contextual problem related to linear equation system in two variables.

Linking Complexity with Cultural Historical Activity Theory

ERIC Educational Resources Information Center

McMurtry, Angus

2006-01-01

This paper explores the similarities and differences between complexity science's and cultural-historical activity theory's understandings of human learning. Notable similarities include their emphasis on the importance of social systems or collectives in understanding human knowledge and practices, as well as their characterization of systems'…

Using the Work System Method with Freshman Information Systems Students

ERIC Educational Resources Information Center

Recker, Jan; Alter, Steven

2012-01-01

Recent surveys of information technology management professionals show that understanding business domains in terms of business productivity and cost reduction potential, knowledge of different vertical industry segments and their information requirements, understanding of business processes and client-facing skills are more critical for…

Inspiring Integration in College Students Reading Multiple Biology Texts

ERIC Educational Resources Information Center

Firetto, Carla

2013-01-01

Introductory biology courses typically present topics on related biological systems across separate chapters and lectures. A complete foundational understanding requires that students understand how these biological systems are related. Unfortunately, spontaneous generation of these connections is rare for novice learners. These experiments focus…

Japanese Children's Understanding of Notational Systems

ERIC Educational Resources Information Center

Takahashi, Noboru

2012-01-01

This study examined Japanese children's understanding of two Japanese notational systems: "hiragana" and "kanji". In three experiments, 126 3- to 6-year-olds were asked to name words written in hiragana or kanji as they appeared with different pictures. Consistent with Bialystok ("Journal of Experimental Child…

How Earth Educators Can Help Students Develop a Holistic Understanding of Sustainability

NASA Astrophysics Data System (ADS)

Curren, R. R.; Metzger, E. P.

2017-12-01

With their expert understanding of planetary systems, Earth educators play a pivotal role in helping students understand the scientific dimensions of solution-resistant ("wicked") challenges to sustainability that arise from complex interactions between intertwined and co-evolving natural and human systems. However, teaching the science of sustainability in isolation from consideration of human values and social dynamics leaves students with a fragmented understanding and obscures the underlying drivers of unsustainability. Geoscience instructors who wish to address sustainability in their courses may feel ill-equipped to engage students in investigation of the fundamental nature of sustainability and its social and ethical facets. This presentation will blend disciplinary perspectives from Earth system science, philosophy, psychology, and anthropology to: 1) outline a way to conceptualize sustainability that synthesizes scientific, social, and ethical perspectives and 2) provide an overview of resources and teaching strategies designed to help students connect science content to the socio-political dimensions of sustainability through activities and assignments that promote active learning, systems thinking, reflection, and collaborative problem-solving.

Revisiting competition in a classic model system using formal links between theory and data.

PubMed

Hart, Simon P; Burgin, Jacqueline R; Marshall, Dustin J

2012-09-01

Formal links between theory and data are a critical goal for ecology. However, while our current understanding of competition provides the foundation for solving many derived ecological problems, this understanding is fractured because competition theory and data are rarely unified. Conclusions from seminal studies in space-limited benthic marine systems, in particular, have been very influential for our general understanding of competition, but rely on traditional empirical methods with limited inferential power and compatibility with theory. Here we explicitly link mathematical theory with experimental field data to provide a more sophisticated understanding of competition in this classic model system. In contrast to predictions from conceptual models, our estimates of competition coefficients show that a dominant space competitor can be equally affected by interspecific competition with a poor competitor (traditionally defined) as it is by intraspecific competition. More generally, the often-invoked competitive hierarchies and intransitivities in this system might be usefully revisited using more sophisticated empirical and analytical approaches.

Laboratory model of the cardiovascular system for experimental demonstration of pulse wave propagation

NASA Astrophysics Data System (ADS)

Stojadinović, Bojana; Nestorović, Zorica; Djurić, Biljana; Tenne, Tamar; Zikich, Dragoslav; Žikić, Dejan

2017-03-01

The velocity by which a disturbance moves through the medium is the wave velocity. Pulse wave velocity is among the key parameters in hemodynamics. Investigation of wave propagation through the fluid-filled elastic tube has a great importance for the proper biophysical understanding of the nature of blood flow through the cardiovascular system. Here, we present a laboratory model of the cardiovascular system. We have designed an experimental setup which can help medical and nursing students to properly learn and understand basic fluid hemodynamic principles, pulse wave and the phenomenon of wave propagation in blood vessels. Demonstration of wave propagation allowed a real time observation of the formation of compression and expansion waves by students, thus enabling them to better understand the difference between the two waves, and also to measure the pulse wave velocity for different fluid viscosities. The laboratory model of the cardiovascular system could be useful as an active learning methodology and a complementary tool for understanding basic principles of hemodynamics.

The Motor System: The Whole and its Parts

PubMed Central

Otten, E.

2001-01-01

Our knowledge of components of the human motor system has been growing steadily, but our understanding of its integration into a system is lagging behind. It is suggested that a combination of measurements of forces and movements of the motor system in a functionally meaningful environment in conjunction with computer simulations of the motor system may help us in understanding motor system properties. Neurotrauma can be seen as a natural deviation, with recovery as a slow path to yet another deviant state of the motor system. In that form they may be useful in explaining the close interaction between form and function of the human motor system. PMID:11530882

Approximate Matching as a Key Technique in Organization of Natural and Artificial Intelligence

NASA Technical Reports Server (NTRS)

Mack, Marilyn; Lapir, Gennadi M.; Berkovich, Simon

2000-01-01

The basic property of an intelligent system, natural or artificial, is "understanding". We consider the following formalization of the idea of "understanding" among information systems. When system I issues a request to system 2, it expects a certain kind of desirable reaction. If such a reaction occurs, system I assumes that its request was "understood". In application to simple, "push-button" systems the situation is trivial because in a small system the required relationship between input requests and desired outputs could be specified exactly. As systems grow, the situation becomes more complex and matching between requests and actions becomes approximate.

The Immune System: Basis of so much Health and Disease: 4. Immunocytes.

PubMed

Scully, Crispian; Georgakopoulou, Eleni A; Hassona, Yazan

2017-05-01

The immune system is the body’s primary defence mechanism against infections, and disturbances in the system can cause disease if the system fails in defence functions (in immunocompromised people), or if the activity is detrimental to the host (as in auto-immune and auto-inflammatory states). A healthy immune system is also essential to normal health of dental and oral tissues. This series presents the basics for the understanding of the immune system, this article covers cells of the immune system (immunocytes). Clinical relevance: Modern dental clinicians need a basic understanding of the immune system as it underlies health and disease.

Mathematical and Computational Modeling in Complex Biological Systems

PubMed Central

Li, Wenyang; Zhu, Xiaoliang

2017-01-01

The biological process and molecular functions involved in the cancer progression remain difficult to understand for biologists and clinical doctors. Recent developments in high-throughput technologies urge the systems biology to achieve more precise models for complex diseases. Computational and mathematical models are gradually being used to help us understand the omics data produced by high-throughput experimental techniques. The use of computational models in systems biology allows us to explore the pathogenesis of complex diseases, improve our understanding of the latent molecular mechanisms, and promote treatment strategy optimization and new drug discovery. Currently, it is urgent to bridge the gap between the developments of high-throughput technologies and systemic modeling of the biological process in cancer research. In this review, we firstly studied several typical mathematical modeling approaches of biological systems in different scales and deeply analyzed their characteristics, advantages, applications, and limitations. Next, three potential research directions in systems modeling were summarized. To conclude, this review provides an update of important solutions using computational modeling approaches in systems biology. PMID:28386558

Mathematical and Computational Modeling in Complex Biological Systems.

PubMed

Ji, Zhiwei; Yan, Ke; Li, Wenyang; Hu, Haigen; Zhu, Xiaoliang

2017-01-01

The biological process and molecular functions involved in the cancer progression remain difficult to understand for biologists and clinical doctors. Recent developments in high-throughput technologies urge the systems biology to achieve more precise models for complex diseases. Computational and mathematical models are gradually being used to help us understand the omics data produced by high-throughput experimental techniques. The use of computational models in systems biology allows us to explore the pathogenesis of complex diseases, improve our understanding of the latent molecular mechanisms, and promote treatment strategy optimization and new drug discovery. Currently, it is urgent to bridge the gap between the developments of high-throughput technologies and systemic modeling of the biological process in cancer research. In this review, we firstly studied several typical mathematical modeling approaches of biological systems in different scales and deeply analyzed their characteristics, advantages, applications, and limitations. Next, three potential research directions in systems modeling were summarized. To conclude, this review provides an update of important solutions using computational modeling approaches in systems biology.

Lessons from Jurassic Park: patients as complex adaptive systems.

PubMed

Katerndahl, David A

2009-08-01

With realization that non-linearity is generally the rule rather than the exception in nature, viewing patients and families as complex adaptive systems may lead to a better understanding of health and illness. Doctors who successfully practise the 'art' of medicine may recognize non-linear principles at work without having the jargon needed to label them. Complex adaptive systems are systems composed of multiple components that display complexity and adaptation to input. These systems consist of self-organized components, which display complex dynamics, ranging from simple periodicity to chaotic and random patterns showing trends over time. Understanding the non-linear dynamics of phenomena both internal and external to our patients can (1) improve our definition of 'health'; (2) improve our understanding of patients, disease and the systems in which they converge; (3) be applied to future monitoring systems; and (4) be used to possibly engineer change. Such a non-linear view of the world is quite congruent with the generalist perspective.

Time to shift from systems thinking-talking to systems thinking-action: Comment on "Constraints to applying systems thinking concepts in health systems: A regional perspective from surveying stakeholders in Eastern Mediterranean countries".

PubMed

Holmes, Bev J; Noel, Kevin

2015-04-01

A recent International Journal of Health Policy and Management (IJHPM) article by Fadi El-Jardali and colleagues makes an important contribution to the literature on health system strengthening by reporting on a survey of healthcare stakeholders in Low- and Middle-Income Countries (LMICs) about Systems Thinking (ST). The study's main contributions are its confirmation that healthcare stakeholders understand the importance of ST but do not know how to act on that understanding, and the call for collective action by the global community of systems thinkers committed to healthcare improvement. We offer three basic considerations for next steps by this community, derived from our recent work in ST and the related field of Knowledge Translation (KT): resist the temptation to adopt a reductionist approach; recognize not everyone needs to understand ST; and do not wait for everything to be in place before getting started.

A history of the autonomic nervous system: part I: from Galen to Bichat.

PubMed

Oakes, Peter C; Fisahn, Christian; Iwanaga, Joe; DiLorenzo, Daniel; Oskouian, Rod J; Tubbs, R Shane

2016-12-01

The development of our current understanding of the autonomic nervous system has a rich history with many international contributors. Although our thoughts of an autonomic nervous system arose with the Greeks, the evolution and final understanding of this neural network would not be fully realized until centuries later. Therefore, our current knowledge of this system is based on hundreds of years of hypotheses and testing and was contributed to by many historic figures.

System Integration and Control in a Speech Understanding System

DTIC Science & Technology

1975-09-01

aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if...visible. a way that allows the The s~cond part of the paper describes an executive that uses information from these knowledge sources in 1ts control...strategy, System Integration and Control Page 1 A speech understanding system must use manY kinds of knowledge , each playing a particular role during

Applied information system-based in enhancing students' understanding towards higher order thinking (HOTS)

NASA Astrophysics Data System (ADS)

Hua, Ang Kean; Ping, Owi Wei

2017-05-01

The application of information and communications technology (ICT) had become more important in our daily life, especially in educational field. Teachers are encouraged to use information system-based in teaching Mathematical courses. Higher Order Thinking Skills (HOTS) approach is unable to explain using chalk and talk methods. It needs students to analyze, evaluate, and create by their own natural abilities. The aim of this research study was to evaluate the effectiveness of the application information system-based in enhance the students understanding about HOTS question. Mixed-methods or quantitative and qualitative approach was applied in collecting data, which involve only the standard five students and the teachers in Sabak Bernam, Selangor. Pra-postests was held before and after using information system-based in teaching to evaluate the students' understanding. The result from post-test indicates significant improvement which proves that the use of information system based able to enhance students' understanding about HOTS question and solve it. There were several factor influenced the students such as students' attitude, teachers attraction, school facilities, and computer approach. Teachers play an important role in attracting students to learn. Therefore, the school should provide a conducive learning environment and good facilities for students to learn so that they are able to access more information and always exposed to new knowledge. As conclusion, information system-based are able to enhance students understanding the need of HOTS questions and solve it.

No question about exciting questions in cell biology.

PubMed

Pollard, Thomas D

2013-12-01

Although we have a good grasp of many important processes in cell biology, including knowledge of many molecules involved and how they interact with each other, we still do not understand most of the dynamical features that are the essence of living systems. Fortunately, we now have the ability to dissect biological systems in enough detail to understand their dynamics, including the use of mathematical models to account for past observations and predict future experiments. This deep level of mechanistic understanding should be our goal—not simply to satisfy our scientific curiosity, but also to understand the causes of disease well enough to predict risks, make early diagnoses, and treat effectively. Many big questions remain to be answered before we reach this goal of understanding cellular dynamics.

Evaluation methodology for query-based scene understanding systems

NASA Astrophysics Data System (ADS)

Huster, Todd P.; Ross, Timothy D.; Culbertson, Jared L.

2015-05-01

In this paper, we are proposing a method for the principled evaluation of scene understanding systems in a query-based framework. We can think of a query-based scene understanding system as a generalization of typical sensor exploitation systems where instead of performing a narrowly defined task (e.g., detect, track, classify, etc.), the system can perform general user-defined tasks specified in a query language. Examples of this type of system have been developed as part of DARPA's Mathematics of Sensing, Exploitation, and Execution (MSEE) program. There is a body of literature on the evaluation of typical sensor exploitation systems, but the open-ended nature of the query interface introduces new aspects to the evaluation problem that have not been widely considered before. In this paper, we state the evaluation problem and propose an approach to efficiently learn about the quality of the system under test. We consider the objective of the evaluation to be to build a performance model of the system under test, and we rely on the principles of Bayesian experiment design to help construct and select optimal queries for learning about the parameters of that model.

Development and Validation of a Two-Tier Instrument to Examine Understanding of Internal Transport in Plants and the Human Circulatory System

ERIC Educational Resources Information Center

Wang, Jing-Ru

2004-01-01

This study is intended to develop an assessment instrument to investigate students' understandings about internal transport in plants and human circulatory system. A refined process of a two-tier diagnostic test was used to develop the instrument. Finally, three versions of the Internal Transport in Plants and the Human Circulatory System test…

A Qualitative Study of Agricultural Literacy in Urban Youth: What Do Elementary Students Understand about the Agri-Food System?

ERIC Educational Resources Information Center

Hess, Alexander J.; Trexler, Cary J.

2011-01-01

Agricultural literacy of K-12 students is a national priority for both scientific and agricultural education professional organizations. Development of curricula to address this priority has not been informed by research on what K-12 students understand about the agri-food system. While students' knowledge of food and fiber system facts have been…

15 CFR 700.63 - Letters of Understanding.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Letters of Understanding. 700.63... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Official Actions § 700.63 Letters of Understanding. (a) A Letter of Understanding is an official action which may be issued in resolving special priorities assistance...

Putting the system back into systems change: a framework for understanding and changing organizational and community systems.

PubMed

Foster-Fishman, Pennie G; Nowell, Branda; Yang, Huilan

2007-06-01

Systems change has emerged as a dominant frame through which local, state, and national funders and practitioners across a wide array of fields approach their work. In most of these efforts, change agents and scholars strive to shift human services and community systems to create better and more just outcomes and improve the status quo. Despite this, there is a dearth of frameworks that scholars, practitioners, and funders can draw upon to aid them in understanding, designing, and assessing this process from a systemic perspective. This paper provides one framework--grounded in systems thinking and change literatures--for understanding and identifying the fundamental system parts and interdependencies that can help to explain system functioning and leverage systems change. The proposed framework highlights the importance of attending to both the deep and apparent structures within a system as well as the interactions and interdependencies among these system parts. This includes attending to the dominant normative, resource, regulative, and operational characteristics that dictate the behavior and lived experiences of system members. The value of engaging critical stakeholders in problem definition, boundary construction, and systems analysis are also discussed. The implications of this framework for systems change researchers and practitioners are discussed.

OZONE AND NATURAL SYSTEMS: UNDERSTANDING EXPOSURE, RESPONSE, AND RISK

EPA Science Inventory

Research aimed at understanding the response of plants to ozone has been conducted for over four decades but little of it has addressed intact natural systems. Even so, there is sufficient information at this time to establish air quality standards that will protect natural terr...

Students' Developing Understanding of Water in Environmental Systems

ERIC Educational Resources Information Center

Covitt, Beth A.; Gunckel, Kristin L.; Anderson, Charles W.

2009-01-01

The authors developed a framework of empirically grounded curricular goals for water-science literacy and documented the challenges that students face in achieving these goals. Water-related environmental science literacy requires an understanding of connected natural and human-engineered systems at multiple scales ranging from atomic-molecular…

Understanding changes of stomatal conductance under different atmospheric humidity levels for different tropical rainforest species in Biosphere 2

NASA Astrophysics Data System (ADS)

Tornito, A. J. G.

2016-12-01

Understanding the dynamics of climate change is one of the biggest questions that scientists across the globe ask today. With understanding climate change comes the need to understand the ecological systems and how their biological and chemical processes contribute to climate change. As ocean ecosystems, rainforests are very productive systems and are responsible for most of the world's carbon budget. To maintain cooler conditions, tropical forests mitigate warming through evapotranspiration. The purpose of this project was to measure short-term plasticity by looking at stomatal conductance levels of different tropical rainforest species of plants in the rainforest, savannah, and desert habitats in the Biosphere 2 facility in Oracle, Arizona. It is known that stomatal conductance is affected by CO2, H2O, and light availability. It has been observed that temperature levels may not affect stomatal conductance because of the variability associated with it. Results indicated that there is a potential trend amongst these rainforest species when placed in different humidity percentage areas. By understanding stomatal conductance in response to humidity, we can better understand how productive rainforest systems are when humidity levels decrease, which may potentially occur as Earth undergoes global climate change.

Geochemistry and the Understanding of Groundwater Systems

NASA Astrophysics Data System (ADS)

Glynn, P. D.; Plummer, L. N.; Weissmann, G. S.; Stute, M.

2009-12-01

Geochemical techniques and concepts have made major contributions to the understanding of groundwater systems. Advances continue to be made through (1) development of measurement and characterization techniques, (2) improvements in computer technology, networks and numerical modeling, (3) investigation of coupled geologic, hydrologic, geochemical and biologic processes, and (4) scaling of individual observations, processes or subsystem models into larger coherent model frameworks. Many applications benefit from progress in these areas, such as: (1) understanding paleoenvironments, in particular paleoclimate, through the use of groundwater archives, (2) assessing the sustainability (recharge and depletion) of groundwater resources, and (3) their vulnerability to contamination, (4) evaluating the capacity and consequences of subsurface waste isolation (e.g. geologic carbon sequestration, nuclear and chemical waste disposal), (5) assessing the potential for mitigation/transformation of anthropogenic contaminants in groundwater systems, and (6) understanding the effect of groundwater lag times in ecosystem-scale responses to natural events, land-use changes, human impacts, and remediation efforts. Obtaining “representative” groundwater samples is difficult and progress in obtaining “representative” samples, or interpreting them, requires new techniques in characterizing groundwater system heterogeneity. Better characterization and simulation of groundwater system heterogeneity (both physical and geochemical) is critical to interpreting the meaning of groundwater “ages”; to understanding and predicting groundwater flow, solute transport, and geochemical evolution; and to quantifying groundwater recharge and discharge processes. Research advances will also come from greater use and progress (1) in the application of environmental tracers to ground water dating and in the analysis of new geochemical tracers (e.g. compound specific isotopic analyses, noble gas isotopes, analyses of natural organic tracers), (2) in inverse geochemical and hydrological modeling, (3) in the understanding and simulation of coupled biological, geological, geochemical and hydrological processes, and (4) in the description and quantification of processes occurring at the boundaries of groundwater systems (e.g. unsaturated zone processes, groundwater/surface water interactions, impacts of changing geomorphology and vegetation). Improvements are needed in the integration of widely diverse information. Better techniques are needed to construct coherent conceptual frameworks from individual observations, simulated or reconstructed information, process models, and intermediate scale models. Iterating between data collection, interpretation, and the application of forward, inverse, and statistical modeling tools is likely to provide progress in this area. Quantifying groundwater system processes by using an open-system thermodynamic approach in a common mass- and energy-flow framework will also facilitate comparison and understanding of diverse processes.

Toward Harnessing User Feedback For Machine Learning

DTIC Science & Technology

2006-10-02

machine learning systems. If this resource-the users themselves-could somehow work hand-in-hand with machine learning systems, the accuracy of learning systems could be improved and the users? understanding and trust of the system could improve as well. We conducted a think-aloud study to see how willing users were to provide feedback and to understand what kinds of feedback users could give. Users were shown explanations of machine learning predictions and asked to provide feedback to improve the predictions. We found that users

An investigation of the role of current and future remote sensing data systems in numerical meteorology

NASA Technical Reports Server (NTRS)

Diak, George R.; Smith, William L.

1992-01-01

A flexible system for performing observing system simulation experiments which made contributions to meteorology across all elements of the observing system simulation experiment (OSSE) components was developed. Future work will seek better understanding of the links between satellite-measured radiation and radiative transfer in the clear, cloudy and precipitating atmosphere and investigate how that understanding might be applied to improve the depiction of the initial state and the treatment of physical processes in forecast models of the atmosphere.

Video-CRM: understanding customer behaviors in stores

NASA Astrophysics Data System (ADS)

Haritaoglu, Ismail; Flickner, Myron; Beymer, David

2013-03-01

This paper describes two real-time computer vision systems created 10 years ago that detect and track people in stores to obtain insights of customer behavior while shopping. The first system uses a single color camera to identify shopping groups in the checkout line. Shopping groups are identified by analyzing the inter-body distances coupled with the cashier's activities to detect checkout transactions start and end times. The second system uses multiple overhead narrow-baseline stereo cameras to detect and track people, their body posture and parts to understand customer interactions with products such as "customer picking a product from a shelf". In pilot studies both systems demonstrated real-time performance and sufficient accuracy to enable more detailed understanding of customer behavior and extract actionable real-time retail analytics.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jansen, F.

The use of integrated PET/MRI systems in clinical applications can best benefit from understanding their technological advances and limitations. The currently available clinical PET/MRI systems have their own characteristics. Thorough analyses of existing technical data and evaluation of necessary performance metrics for quality assurances could be conducted to optimize application-specific PET/MRI protocols. This Symposium will focus on technical advances and limitations of clinical PET/MRI systems, and how this exciting imaging modality can be utilized in applications that can benefit from both PET and MRI. Learning Objectives: To understand the technological advances of clinical PET/MRI systems To correctly identify clinical applicationsmore » that can benefit from PET/MRI To understand ongoing work to further improve the current PET/MRI technology Floris Jansen is a GE Healthcare employee.« less

Plant Systems Biology at the Single-Cell Level.

PubMed

Libault, Marc; Pingault, Lise; Zogli, Prince; Schiefelbein, John

2017-11-01

Our understanding of plant biology is increasingly being built upon studies using 'omics and system biology approaches performed at the level of the entire plant, organ, or tissue. Although these approaches open new avenues to better understand plant biology, they suffer from the cellular complexity of the analyzed sample. Recent methodological advances now allow plant scientists to overcome this limitation and enable biological analyses of single-cells or single-cell-types. Coupled with the development of bioinformatics and functional genomics resources, these studies provide opportunities for high-resolution systems analyses of plant phenomena. In this review, we describe the recent advances, current challenges, and future directions in exploring the biology of single-cells and single-cell-types to enhance our understanding of plant biology as a system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Understanding the immune response to seasonal influenza vaccination in older adults: a systems biology approach.

PubMed

Lambert, Nathaniel D; Ovsyannikova, Inna G; Pankratz, V Shane; Jacobson, Robert M; Poland, Gregory A

2012-08-01

Annual vaccination against seasonal influenza is recommended to decrease disease-related mortality and morbidity. However, one population that responds suboptimally to influenza vaccine is adults over the age of 65 years. The natural aging process is associated with a complex deterioration of multiple components of the host immune system. Research into this phenomenon, known as immunosenescence, has shown that aging alters both the innate and adaptive branches of the immune system. The intricate mechanisms involved in immune response to influenza vaccine, and how these responses are altered with age, have led us to adopt a more encompassing systems biology approach to understand exactly why the response to vaccination diminishes with age. Here, the authors review what changes occur with immunosenescence, and some immunogenetic factors that influence response, and outline the systems biology approach to understand the immune response to seasonal influenza vaccination in older adults.

Managing Systemic Change: Future Roles for Social Learning Systems and Communities of Practice?

NASA Astrophysics Data System (ADS)

Blackmore, Chris

The Open University course that prompted this book, and for which it is part of the required reading, focuses on managing systemic change. The course is designed for people who want to develop their skills and understanding in systems thinking and practice, to be used in a range of different domains. Most of the examples in the course come from work-based settings. The idea of managing in this context is mainly about appreciating situations with others, recognising what actions are desirable and feasible and for whom, and getting organised, in order to affect or respond to change in a positive way. It has little to do with control. As Vickers (1978, p. 81) said 'I do not think it too much to hope that an understanding of systemic relations may bring us a better understanding of our limitations and even our possibilities.'

A systemic approach to understanding mental health and services.

PubMed

Cohen, Mark

2017-10-01

In the UK mental health and associated NHS services face considerable challenges. This paper aims to form an understanding both of the complexity of context in which services operate and the means by which services have sought to meet these challenges. Systemic principles as have been applied to public service organisations with reference to interpersonal relations, the wider social culture and its manifestation in service provision. The analysis suggests that the wider culture has shaped service demand and the approaches adopted by services resulting in a number of unintended consequences, reinforcing loops, increased workload demands and the limited value of services. The systemic modelling of this situation provides a necessary overview prior to future policy development. The paper concludes that mental health and attendant services requires a systemic understanding and a whole system approach to reform. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Our changing planet: The FY 1993 US global change research program. A supplement to the US President's fiscal year 1993 budget

NASA Technical Reports Server (NTRS)

1992-01-01

An improved predictive understanding of the integrated Earth system, including human interactions, will provide direct benefits by anticipating and planning for possible impacts on commerce, agriculture, energy, resource utilization, human safety, and environmental quality. The central goal of the U.S. Global Change Research Program (USGCRP) is to help establish the scientific understanding and the basis for national and international policymaking related to natural and human-induced changes in the global Earth system. This will be accomplished through: (1) establishing an integrated, comprehensive, long-term program of documenting the Earth system on a global scale; (2) conducting a program of focused studies to improve our understanding of the physical, geological, chemical, biological, and social processes that influence the Earth system processes; and (3) developing integrated conceptual and predictive Earth system models.

Understanding School System Administration: Studies of the Contemporary Chief Education Officer. Educational Policy Perspective Series.

ERIC Educational Resources Information Center

Leithwood, Kenneth, Ed.; Musella, Donald, Ed.

This volume presents several distinctive but related empirical studies and opinion pieces about chief education officers (CEOs). The collection begins with (1) "Introduction: A Framework for Understanding School System Administration" (Kenneth Leithwood and Donald Musella). Section A, "Chief Education Officers' Practices and…

Understanding Competence. A Development Paper.

ERIC Educational Resources Information Center

National Inst. of Adult Continuing Education, Leicester (England). Unit for the Development of Adult Continuing Education.

Competence is one of the outcomes of learning. Competence embraces both specific task skills and the understanding, knowledge, attitude, and personal skills required to carry out that task effectively. An education and training system built on a broad definition of competence would give greater control to the users of the system (the individuals…

Visuals and Visualisation of Human Body Systems

ERIC Educational Resources Information Center

Mathai, Sindhu; Ramadas, Jayashree

2009-01-01

This paper explores the role of diagrams and text in middle school students' understanding and visualisation of human body systems. We develop a common framework based on structure and function to assess students' responses across diagram and verbal modes. Visualisation is defined in terms of understanding transformations on structure and relating…

On the Importance of Coherence in the Study of Character Development

ERIC Educational Resources Information Center

Callina, Kristina Schmid; Lerner, Richard M.

2017-01-01

Nucci (this issue) gives a compelling conceptualization of the ideas needed to understand character as a multifaceted developmental system. In this article, we focus on the idea of coherence as it applies to understanding character development, education, and assessment. Using ideas from relational developmental systems (RDS) metatheory, we…

Towards a Systemic Theory of Gifted Education

ERIC Educational Resources Information Center

Ziegler, Albert; Phillipson, Shane N.

2012-01-01

In this target article, we argue that current approaches to gifted education are based on the erroneous view that to understand the development of exceptionality we need to understand firstly the components of giftedness, including cognitive such as intelligence and non-cognitive factors such as motivation. In contrast, systemic approaches to…

Virtual Solar System Project: Building Understanding through Model Building.

ERIC Educational Resources Information Center

Barab, Sasha A.; Hay, Kenneth E.; Barnett, Michael; Keating, Thomas

2000-01-01

Describes an introductory astronomy course for undergraduate students in which students use three-dimensional (3-D) modeling tools to model the solar system and develop rich understandings of astronomical phenomena. Indicates that 3-D modeling can be used effectively in regular undergraduate university courses as a tool to develop understandings…

Understanding the Impact of Individual Differences on Learner Performance Using Hypermedia Systems

ERIC Educational Resources Information Center

Alhajri, Rana; Alhunaiyyan, Ahmed A.; AlMousa, Eba'

2017-01-01

In recent studies, there has been focus on understanding learner performance and behaviour using Web-Based Instruction (WBI) systems which accommodate individual differences. Studies have investigated the performance of these differences individually such as gender, cognitive style and prior knowledge. In this article, the authors describe a…

Fear, Loathing and Ambivalence toward Learning and Teaching Mathematics: Preservice Teachers' Perspectives

ERIC Educational Resources Information Center

Itter, Diane; Meyers, Noel

2017-01-01

Preservice teachers graduate from an education system that shapes their mathematical understandings, beliefs and attitudes, and then re-enter that system to shape their own students' mathematical understandings, beliefs, and attitudes. Unfortunately, many of our future teachers have developed negative attitudes symptomatic of a self-perpetuating…

Web-based e-learning and virtual lab of human-artificial immune system.

PubMed

Gong, Tao; Ding, Yongsheng; Xiong, Qin

2014-05-01

Human immune system is as important in keeping the body healthy as the brain in supporting the intelligence. However, the traditional models of the human immune system are built on the mathematics equations, which are not easy for students to understand. To help the students to understand the immune systems, a web-based e-learning approach with virtual lab is designed for the intelligent system control course by using new intelligent educational technology. Comparing the traditional graduate educational model within the classroom, the web-based e-learning with the virtual lab shows the higher inspiration in guiding the graduate students to think independently and innovatively, as the students said. It has been found that this web-based immune e-learning system with the online virtual lab is useful for teaching the graduate students to understand the immune systems in an easier way and design their simulations more creatively and cooperatively. The teaching practice shows that the optimum web-based e-learning system can be used to increase the learning effectiveness of the students.

Imitation and Action Understanding in Autistic Spectrum Disorders: How Valid Is the Hypothesis of a Deficit in the Mirror Neuron System?

ERIC Educational Resources Information Center

Hamilton, Antonia F. de C.; Brindley, Rachel M.; Frith, Uta

2007-01-01

The motor mirror neuron system supports imitation and goal understanding in typical adults. Recently, it has been proposed that a deficit in this mirror neuron system might contribute to poor imitation performance in children with autistic spectrum disorders (ASD) and might be a cause of poor social abilities in these children. We aimed to test…

Information Fusion Issues in the UK Environmental Science Community

NASA Astrophysics Data System (ADS)

Giles, J. R.

2010-12-01

The Earth is a complex, interacting system which cannot be neatly divided by discipline boundaries. To gain an holistic understanding of even a component of an Earth System requires researchers to draw information from multiple disciplines and integrate these to develop a broader understanding. But the barriers to achieving this are formidable. Research funders attempting to encourage the integration of information across disciplines need to take into account culture issues, the impact of intrusion of projects on existing information systems, ontologies and semantics, scale issues, heterogeneity and the uncertainties associated with combining information from diverse sources. Culture - There is a cultural dualism in the environmental sciences were information sharing is both rewarded and discouraged. Researchers who share information both gain new opportunities and risk reducing their chances of being first author in an high-impact journal. The culture of the environmental science community has to be managed to ensure that information fusion activities are encouraged. Intrusion - Existing information systems have an inertia of there own because of the intellectual and financial capital invested within them. Information fusion activities must recognise and seek to minimise the potential impact of their projects on existing systems. Low intrusion information fusions systems such as OGC web-service and the OpenMI Standard are to be preferred to whole-sale replacement of existing systems. Ontology and Semantics - Linking information across disciplines requires a clear understanding of the concepts deployed in the vocabulary used to describe them. Such work is a critical first step to creating routine information fusion. It is essential that national bodies, such as geological surveys organisations, document and publish their ontologies, semantics, etc. Scale - Environmental processes operate at scales ranging from microns to the scale of the Solar System and potentially beyond. The many different scales involved provide serious challenges to information fusion which need to be researched. Heterogeneity - Natural systems are heterogeneous, that is a system consisting of multiple components each of which may have considerable internal variation. Modelling Earth Systems requires recognition of the inherent complexity. Uncertainty - Understanding the uncertainties within a single information source can be difficult. Understanding the uncertainties across a system of linked models, each drawn from multiple information resources, represents a considerable challenge that must be addressed. The challenges to overcome appear insurmountable to individual research groups; but the potential rewards, in terms of a fuller scientific understanding of Earth Systems, are significant. A major international effort must be mounted to tackle these barriers and enable routine information fusion.

Reforming the road freight transportation system using systems thinking: An investigation of Coronial inquests in Australia.

PubMed

Newnam, Sharon; Goode, Natassia; Salmon, Paul; Stevenson, Mark

2017-04-01

Road freight transport is considered to be one of the most dangerous industries in Australia, accounting for over 30% of all work fatalities. Whilst system reform (i.e., change to policy and practice) is needed, it is not clear what this reform should be, or what approaches should be used to drive it. This article argues that road freight transportation reform should be underpinned by a systems thinking approach. Efforts to understand crash causation should be focused beyond the driver and identify contributing factors at other levels with the road freight system. Accordingly, we present the findings from a study that examined whether Australian Coronial investigations into road freight crashes reflect support appropriate system reform. Content analysis was used to identify the contributing factors and interrelations implicated in the road freight crashes described in publicly available Australian Coroner's inquest reports from the last 10 years (2004-2014; n=21). The results found evidence to suggest that the Coronial inquests provide some understanding of the complex system of factors influencing road freight transportation crashes in Australia. However, there was a lack of evidence to suggest an understanding of system-based reform based on the identification of reductionist-focused recommendations. It is concluded that researchers and practitioners (ie., government and industry) need to work together to develop prevention efforts focused on system reforms. Systems thinking based data collection and analysis frameworks are urgently required to help develop this understanding in road freight transportation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Understanding multinational companies in public health systems, using a competitive advantage framework

PubMed Central

2011-01-01

Background This paper discusses the findings of a study which developed five case studies of five multinational health care companies involved in public health care systems. Strategies were analysed in terms of attitude to marketing, pricing and regulation. The company strategies have been subjected to an analysis using Porter's Five Forces, a business strategy framework, which is unusual in health policy studies. Methods This paper shows how analysing company strategy using a business tool can contribute to understanding the strategies of global capital in national health systems. It shows how social science methodologies can draw from business methods to explain company strategies. Results The five companies considered in this paper demonstrate that their strategies have many dimensions, which fit into Porter's Five Forces of comparative advantage. More importantly the Five Forces can be used to identify factors that influence company entry into public health care systems. Conclusions The process of examining the strategic objectives of five health care companies shows that a business tool can help to explain the actions and motives of health care companies towards public health care systems, and so contribute to a better understanding of the strategies of global capital in national health systems. Health service commissioners need to understand this dynamic process, which will evolve as the nature of public health care systems change. PMID:21722372

Extracting semantics from audio-visual content: the final frontier in multimedia retrieval.

PubMed

Naphade, M R; Huang, T S

2002-01-01

Multimedia understanding is a fast emerging interdisciplinary research area. There is tremendous potential for effective use of multimedia content through intelligent analysis. Diverse application areas are increasingly relying on multimedia understanding systems. Advances in multimedia understanding are related directly to advances in signal processing, computer vision, pattern recognition, multimedia databases, and smart sensors. We review the state-of-the-art techniques in multimedia retrieval. In particular, we discuss how multimedia retrieval can be viewed as a pattern recognition problem. We discuss how reliance on powerful pattern recognition and machine learning techniques is increasing in the field of multimedia retrieval. We review the state-of-the-art multimedia understanding systems with particular emphasis on a system for semantic video indexing centered around multijects and multinets. We discuss how semantic retrieval is centered around concepts and context and the various mechanisms for modeling concepts and context.

Understanding Biological Regulation Through Synthetic Biology.

PubMed

Bashor, Caleb J; Collins, James J

2018-05-20

Engineering synthetic gene regulatory circuits proceeds through iterative cycles of design, building, and testing. Initial circuit designs must rely on often-incomplete models of regulation established by fields of reductive inquiry-biochemistry and molecular and systems biology. As differences in designed and experimentally observed circuit behavior are inevitably encountered, investigated, and resolved, each turn of the engineering cycle can force a resynthesis in understanding of natural network function. Here, we outline research that uses the process of gene circuit engineering to advance biological discovery. Synthetic gene circuit engineering research has not only refined our understanding of cellular regulation but furnished biologists with a toolkit that can be directed at natural systems to exact precision manipulation of network structure. As we discuss, using circuit engineering to predictively reorganize, rewire, and reconstruct cellular regulation serves as the ultimate means of testing and understanding how cellular phenotype emerges from systems-level network function.

From biological and social network metaphors to coupled bio-social wireless networks

PubMed Central

Barrett, Christopher L.; Eubank, Stephen; Anil Kumar, V.S.; Marathe, Madhav V.

2010-01-01

Biological and social analogies have been long applied to complex systems. Inspiration has been drawn from biological solutions to solve problems in engineering products and systems, ranging from Velcro to camouflage to robotics to adaptive and learning computing methods. In this paper, we present an overview of recent advances in understanding biological systems as networks and use this understanding to design and analyse wireless communication networks. We expand on two applications, namely cognitive sensing and control and wireless epidemiology. We discuss how our work in these two applications is motivated by biological metaphors. We believe that recent advances in computing and communications coupled with advances in health and social sciences raise the possibility of studying coupled bio-social communication networks. We argue that we can better utilise the advances in our understanding of one class of networks to better our understanding of the other. PMID:21643462

Tele-auscultation support system with mixed reality navigation.

PubMed

Hori, Kenta; Uchida, Yusuke; Kan, Tsukasa; Minami, Maya; Naito, Chisako; Kuroda, Tomohiro; Takahashi, Hideya; Ando, Masahiko; Kawamura, Takashi; Kume, Naoto; Okamoto, Kazuya; Takemura, Tadamasa; Yoshihara, Hiroyuki

2013-01-01

The aim of this research is to develop an information support system for tele-auscultation. In auscultation, a doctor requires to understand condition of applying a stethoscope, in addition to auscultatory sounds. The proposed system includes intuitive navigation system of stethoscope operation, in addition to conventional audio streaming system of auscultatory sounds and conventional video conferencing system for telecommunication. Mixed reality technology is applied for intuitive navigation of the stethoscope. Information, such as position, contact condition and breath, is overlaid on a view of the patient's chest. The contact condition of the stethoscope is measured by e-textile contact sensors. The breath is measured by a band type breath sensor. In a simulated tele-auscultation experiment, the stethoscope with the contact sensors and the breath sensor were evaluated. The results show that the presentation of the contact condition was not understandable enough for navigating the stethoscope handling. The time series of the breath phases was usable for the remote doctor to understand the breath condition of the patient.

Systems Biology-Based Platforms to Accelerate Research of Emerging Infectious Diseases.

PubMed

Oh, Soo Jin; Choi, Young Ki; Shin, Ok Sarah

2018-03-01

Emerging infectious diseases (EIDs) pose a major threat to public health and security. Given the dynamic nature and significant impact of EIDs, the most effective way to prevent and protect against them is to develop vaccines in advance. Systems biology approaches provide an integrative way to understand the complex immune response to pathogens. They can lead to a greater understanding of EID pathogenesis and facilitate the evaluation of newly developed vaccine-induced immunity in a timely manner. In recent years, advances in high throughput technologies have enabled researchers to successfully apply systems biology methods to analyze immune responses to a variety of pathogens and vaccines. Despite recent advances, computational and biological challenges impede wider application of systems biology approaches. This review highlights recent advances in the fields of systems immunology and vaccinology, and presents ways that systems biology-based platforms can be applied to accelerate a deeper understanding of the molecular mechanisms of immunity against EIDs. © Copyright: Yonsei University College of Medicine 2018.

Systems Biology-Based Platforms to Accelerate Research of Emerging Infectious Diseases

PubMed Central

2018-01-01

Emerging infectious diseases (EIDs) pose a major threat to public health and security. Given the dynamic nature and significant impact of EIDs, the most effective way to prevent and protect against them is to develop vaccines in advance. Systems biology approaches provide an integrative way to understand the complex immune response to pathogens. They can lead to a greater understanding of EID pathogenesis and facilitate the evaluation of newly developed vaccine-induced immunity in a timely manner. In recent years, advances in high throughput technologies have enabled researchers to successfully apply systems biology methods to analyze immune responses to a variety of pathogens and vaccines. Despite recent advances, computational and biological challenges impede wider application of systems biology approaches. This review highlights recent advances in the fields of systems immunology and vaccinology, and presents ways that systems biology-based platforms can be applied to accelerate a deeper understanding of the molecular mechanisms of immunity against EIDs. PMID:29436184

Interactions Among Plants, Insects, and Microbes: Elucidation of Inter-Organismal Chemical Communications in Agricultural Ecology.

PubMed

Beck, John J; Alborn, Hans; Block, Anna; Christensen, Shawn A; Hunter, Charles T; Rering, Caitlin C; Seidl-Adams, Irmgard; Stuhl, Charles; Torto, Baldwyn; Tumlinson, James H

2018-06-12

The last two decades have witnessed a sustained increase in the study of plant-emitted volatiles and their role in plant-insect, plant-microbe and plant-plant interactions. While each of these binary systems involves complex chemical and biochemical processes between two organisms, the progression of increasing complexity of a ternary system (i.e., plant-insect-microbe), and the study of a ternary system requires non-trivial planning. This planning can include: an experimental design that factors in potential overarching ecological interactions regarding the binary or ternary system; correctly identifying and understanding unexpected observations that may occur during the experiment; and, thorough interpretation of the resultant data. This challenge of planning, performing and interpreting a plant's defensive response to multiple biotic stressors will be even greater when abiotic stressors (i.e., temperature or water) are factored into the system. To fully understand the system, we need to not only continue to investigate and understand the volatile profiles, but also include and understand the biochemistry of the plant's response to these stressors. In this paper, we provide examples and discuss interaction considerations with respect to how readers and future authors of the Journal of Agricultural and Food Chemistry can contribute their expertise toward the extraction and interpretation of chemical information exchanged between agricultural commodities and their associated pests. This holistic, multidisciplinary and thoughtful approach to interactions of plants, insects, and microbes, and the resultant response of the plants, can lead to a better understanding of agricultural ecology, in turn leading to practical and viable solutions to agricultural problems.

Toward a multiscale modeling framework for understanding serotonergic function

PubMed Central

Wong-Lin, KongFatt; Wang, Da-Hui; Moustafa, Ahmed A; Cohen, Jeremiah Y; Nakamura, Kae

2017-01-01

Despite its importance in regulating emotion and mental wellbeing, the complex structure and function of the serotonergic system present formidable challenges toward understanding its mechanisms. In this paper, we review studies investigating the interactions between serotonergic and related brain systems and their behavior at multiple scales, with a focus on biologically-based computational modeling. We first discuss serotonergic intracellular signaling and neuronal excitability, followed by neuronal circuit and systems levels. At each level of organization, we will discuss the experimental work accompanied by related computational modeling work. We then suggest that a multiscale modeling approach that integrates the various levels of neurobiological organization could potentially transform the way we understand the complex functions associated with serotonin. PMID:28417684

Understanding natural language for spacecraft sequencing

NASA Technical Reports Server (NTRS)

Katz, Boris; Brooks, Robert N., Jr.

1987-01-01

The paper describes a natural language understanding system, START, that translates English text into a knowledge base. The understanding and the generating modules of START share a Grammar which is built upon reversible transformations. Users can retrieve information by querying the knowledge base in English; the system then produces an English response. START can be easily adapted to many different domains. One such domain is spacecraft sequencing. A high-level overview of sequencing as it is practiced at JPL is presented in the paper, and three areas within this activity are identified for potential application of the START system. Examples are given of an actual dialog with START based on simulated data for the Mars Observer mission.

Building an Open Source Framework for Integrated Catchment Modeling

NASA Astrophysics Data System (ADS)

Jagers, B.; Meijers, E.; Villars, M.

2015-12-01

In order to develop effective strategies and associated policies for environmental management, we need to understand the dynamics of the natural system as a whole and the human role therein. This understanding is gained by comparing our mental model of the world with observations from the field. However, to properly understand the system we should look at dynamics of water, sediments, water quality, and ecology throughout the whole system from catchment to coast both at the surface and in the subsurface. Numerical models are indispensable in helping us understand the interactions of the overall system, but we need to be able to update and adjust them to improve our understanding and test our hypotheses. To support researchers around the world with this challenging task we started a few years ago with the development of a new open source modeling environment DeltaShell that integrates distributed hydrological models with 1D, 2D, and 3D hydraulic models including generic components for the tracking of sediment, water quality, and ecological quantities throughout the hydrological cycle composed of the aforementioned components. The open source approach combined with a modular approach based on open standards, which allow for easy adjustment and expansion as demands and knowledge grow, provides an ideal starting point for addressing challenging integrated environmental questions.

Impact of audio narrated animation on students' understanding and learning environment based on gender

NASA Astrophysics Data System (ADS)

Nasrudin, Ajeng Ratih; Setiawan, Wawan; Sanjaya, Yayan

2017-05-01

This study is titled the impact of audio narrated animation on students' understanding in learning humanrespiratory system based on gender. This study was conducted in eight grade of junior high school. This study aims to investigate the difference of students' understanding and learning environment at boys and girls classes in learning human respiratory system using audio narrated animation. Research method that is used is quasy experiment with matching pre-test post-test comparison group design. The procedures of study are: (1) preliminary study and learning habituation using audio narrated animation; (2) implementation of learning using audio narrated animation and taking data; (3) analysis and discussion. The result of analysis shows that there is significant difference on students' understanding and learning environment at boys and girls classes in learning human respiratory system using audio narrated animation, both in general and specifically in achieving learning indicators. The discussion related to the impact of audio narrated animation, gender characteristics, and constructivist learning environment. It can be concluded that there is significant difference of students' understanding at boys and girls classes in learning human respiratory system using audio narrated animation. Additionally, based on interpretation of students' respond, there is the difference increment of agreement level in learning environment.

Systems immunology: just getting started.

PubMed

Davis, Mark M; Tato, Cristina M; Furman, David

2017-06-20

Systems-biology approaches in immunology take various forms, but here we review strategies for measuring a broad swath of immunological functions as a means of discovering previously unknown relationships and phenomena and as a powerful way of understanding the immune system as a whole. This approach has rejuvenated the field of vaccine development and has fostered hope that new ways will be found to combat infectious diseases that have proven refractory to classical approaches. Systems immunology also presents an important new strategy for understanding human immunity directly, taking advantage of the many ways the immune system of humans can be manipulated.

Systems immunology: just getting started

PubMed Central

Davis, Mark M; Tato, Cristina M; Furman, David

2018-01-01

Systems-biology approaches in immunology take various forms, but here we review strategies for measuring a broad swath of immunological functions as a means of discovering previously unknown relationships and phenomena and as a powerful way of understanding the immune system as a whole. This approach has rejuvenated the field of vaccine development and has fostered hope that new ways will be found to combat infectious diseases that have proven refractory to classical approaches. Systems immunology also presents an important new strategy for understanding human immunity directly, taking advantage of the many ways the immune system of humans can be manipulated. PMID:28632713

Honey bee surveillance: a tool for understanding and improving honey bee health.

PubMed

Lee, Kathleen; Steinhauer, Nathalie; Travis, Dominic A; Meixner, Marina D; Deen, John; vanEngelsdorp, Dennis

2015-08-01

Honey bee surveillance systems are increasingly used to characterize honey bee health and disease burdens of bees in different regions and/or over time. In addition to quantifying disease prevalence, surveillance systems can identify risk factors associated with colony morbidity and mortality. Surveillance systems are often observational, and prove particularly useful when searching for risk factors in real world complex systems. We review recent examples of surveillance systems with particular emphasis on how these efforts have helped increase our understanding of honey bee health. Copyright © 2015 Elsevier Inc. All rights reserved.

Earth observing system: 1989 reference handbook

NASA Technical Reports Server (NTRS)

1989-01-01

NASA is studying a coordinated effort called the Mission to Planet Earth to understand global change. The goals are to understand the Earth as a system, and to determine those processes that contribute to the environmental balance, as well as those that may result in changes. The Earth Observing System (Eos) is the centerpiece of the program. Eos will create an integrated scientific observing system that will enable multidisciplinary study of the Earth including the atmosphere, oceans, land surface, polar regions, and solid Earth. Science goals, the Eos data and information system, experiments, measuring instruments, and interdisciplinary investigations are described.

Social-Ecological Resilience and Environmental Education: Synopsis, Application, Implications

ERIC Educational Resources Information Center

Plummer, Ryan

2010-01-01

The resilience approach is rooted in ecology and is being advanced as a means to understand change in social-ecological systems. How can resilience be applied to understanding change in social systems, including in environmental education? In probing this question the main resilience approaches are described, the manner in which they may be…

A Study of Students' Reasoning about Probabilistic Causality: Implications for Understanding Complex Systems and for Instructional Design

ERIC Educational Resources Information Center

Grotzer, Tina A.; Solis, S. Lynneth; Tutwiler, M. Shane; Cuzzolino, Megan Powell

2017-01-01

Understanding complex systems requires reasoning about causal relationships that behave or appear to behave probabilistically. Features such as distributed agency, large spatial scales, and time delays obscure co-variation relationships and complex interactions can result in non-deterministic relationships between causes and effects that are best…

Salient Beliefs in Majoring in Management Information Systems: An Elicitation Study

ERIC Educational Resources Information Center

Chipidza, Wallace; Green, Gina; Riemenschneider, Cindy

2016-01-01

Research utilizing the Theory of Planned Behavior to understand behavior should first elicit beliefs about the phenomenon from the target population. In order to understand the reasons why students choose to major or not major in Management Information Systems (MIS), we elicited beliefs from 136 students attending university in the United States…

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT III, AUTOMATIC TRANSMISSIONS--HYDRAULICS (PART I).

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO INTRODUCE BASIC HYDRAULIC PRINCIPLES AND PROVIDE AN UNDERSTANDING OF HYDRAULIC TRANSMISSIONS USED IN DIESEL POWERED VEHICLES. TOPICS ARE WHY USE HYDRAULICS, REVIEWING BASIC PHYSICS LAWS IN RELATION TO HYDRAULICS, UNDERSTANDING THE HYDRAULIC SYSTEM, AND DEVELOPING A BASIC HYDRAULIC SYSTEM. THE MODULE…

Understanding the business of employed physician practices.

PubMed

Sanford, Kathleen D

2013-09-01

Health system leaders should understand issues related to finance, compliance, human resources, quality, and safety in their employed physician practices to better support the success of these practices. New business and payment models are driving operational changes in physician offices. Catholic Health Initiatives (CHI) has added new system roles and responsibilities to oversee physician practices.

Islam through the History and Culture of Pakistan. Fulbright-Hays Summer Seminar Abroad Project, 1994.

ERIC Educational Resources Information Center

Wilson, William E.

This project introduces a syllabus for studying comparative politics among Canada, Pakistan, and Japan. Students learn that comparative politics provides an understanding of how different political systems operate and the importance of culture in understanding politics. Three functions are addressed in the course: system functions, process…

Understanding Suicide among Sexual Minority Youth in America: An Ecological Systems Analysis

ERIC Educational Resources Information Center

Hong, Jun Sung; Espelage, Dorothy L.; Kral, Michael J.

2011-01-01

This article examines major risk factors for suicide among sexual minority youth using Bronfenbrenner's ecological systems theory. Although suicidal behavior among sexual minority youth is a major public concern in the United States, understanding of this phenomenon has been limited since the majority of empirical research studies have addressed…

Semantic Grammar: An Engineering Technique for Constructing Natural Language Understanding Systems.

ERIC Educational Resources Information Center

Burton, Richard R.

In an attempt to overcome the lack of natural means of communication between student and computer, this thesis addresses the problem of developing a system which can understand natural language within an educational problem-solving environment. The nature of the environment imposes efficiency, habitability, self-teachability, and awareness of…

Connecting Earth Systems: Developing Holistic Understanding through the Earth-System-Science Model

ERIC Educational Resources Information Center

Gagnon, Valoree; Bradway, Heather

2012-01-01

For many years, Earth science concepts have been taught as thematic units with lessons in nice, neat chapter packages complete with labs and notes. But compartmentalized Earth science no longer exists, and implementing teaching methods that support student development of holistic understandings can be a time-consuming and difficult task. While…

Understanding of Relation Structures of Graphical Models by Lower Secondary Students

ERIC Educational Resources Information Center

van Buuren, Onne; Heck, André; Ellermeijer, Ton

2016-01-01

A learning path has been developed on system dynamical graphical modelling, integrated into the Dutch lower secondary physics curriculum. As part of the developmental research for this learning path, students' understanding of the relation structures shown in the diagrams of graphical system dynamics based models has been investigated. One of our…

Students' Understanding of Equilibrium and Stability: The Case of Dynamic Systems

ERIC Educational Resources Information Center

Canu, Michaël; de Hosson, Cécile; Duque, Mauricio

2016-01-01

Engineering students in control courses have been observed to lack an understanding of equilibrium and stability, both of which are crucial concepts in this discipline. The introduction of these concepts is generally based on the study of classical examples from Newtonian mechanics supplemented with a control system. Equilibrium and stability are…

The Cultural Understanding of Inclusion and Its Development within a Centralised System

ERIC Educational Resources Information Center

Strogilos, Vasilis

2012-01-01

This paper discusses inclusion in relation to centralised systems, in particular the constraints central control makes upon decisions at school level. The discussion is empowered by an evaluative case study research undertaken to understand the development of inclusion in contexts where flexible teaching and curriculum change are sometimes hard to…

Exploring Novel Tools for Assessing High School Students' Meaningful Understanding of Organic Reactions

ERIC Educational Resources Information Center

Vachliotis, Theodoros; Salta, Katerina; Vasiliou, Petroula; Tzougraki, Chryssa

2011-01-01

Systemic assessment questions (SAQs) are novel assessment tools used in the context of the Systemic Approach to Teaching and Learning (SATL) model. The purpose of this model is to enhance students' meaningful understanding of scientific concepts by use of constructivist concept mapping procedures, which emphasize the development of systems…

Early Elementary Students' Understanding of Complex Ecosystems: A Learning Progression Approach

ERIC Educational Resources Information Center

Hokayem, Hayat; Gotwals, Amelia Wenk

2016-01-01

Engaging in systemic reasoning about ecological issues is critical for early elementary students to develop future understanding of critical environmental issues such as global warming and loss of biodiversity. However, ecological issues are rarely taught in ways to highlight systemic reasoning in elementary schools. In this study, we conducted…

Exploring the Decision Landscape: Integration and Display of Ecosystem Services & Indicators Using the Driver-Pressure-State-Impact-Response Framework and Dynamic Web Application

EPA Science Inventory

Making decisions to increase community or regional sustainability requires a comprehensive understanding of the linkages between environmental, social, and economic systems. We present a visualization tool that can improve decision processes by enhancing understanding of system c...

Discerning Technological Systems Related to Everyday Objects: Mapping the Variation in Pupils' Experience

ERIC Educational Resources Information Center

Svensson, Maria; Ingerman, Ake

2010-01-01

Understanding technology today implies more than being able to use the technological objects present in our everyday lives. Our society is increasingly integrated with technological systems, of which technological objects, and their function, form a part. Technological literacy in that context implies understanding how knowledge is constituted in…

Role of ICT in Shaping the Future of Pakistani Higher Education System

ERIC Educational Resources Information Center

Shaikh, Zaffar Ahmed; Khoja, Shakeel Ahmed

2011-01-01

This study examined the challenges faced by the Pakistani higher education system (HES) in integrating information and communication technology (ICT); it aimed at understanding ICT needs, measuring the increase in ICT demand, determining the relationship between ICT and HES performance, and understanding how the HES copes with the challenges of…

The Effect of Functional Flow Diagrams on Apprentice Aircraft Mechanics' Technical System Understanding.

ERIC Educational Resources Information Center

Johnson, Scott D.; Satchwell, Richard E.

1993-01-01

Describes an experimental study that tested the impact of a conceptual illustration on college students' understanding of the structure, function, and behavior of complex technical systems. The use of functional flow diagrams in aircraft mechanics' training is explained, a concept map analysis is discussed, and implications for technical training…

A Manual for Understanding and Improving Counselor/Client Interview Behavior.

ERIC Educational Resources Information Center

Santoro, David A.

This manual was devised to help supervisors, counselors, trainees, and other educators to better understand and improve counselor/client interview behavior through utilization of the Counselor Client Behavior Analysis System (CCBA). The CCBA is an interaction training and/or research schema designed to provide a formalized feedback system on the…

Understanding the Earth Systems of Malawi: Ecological Sustainability, Culture, and Place-Based Education

ERIC Educational Resources Information Center

Glasson, George E.; Frykholm, Jeffrey A.; Mhango, Ndalapa A.; Phiri, Absalom D.

2006-01-01

The purpose of this 2-year study was to investigate Malawian teacher educators' perspectives and dispositions toward teaching about ecological sustainability issues in Malawi, a developing country in sub-Sahara Africa. This study was embedded in a larger theoretical framework of investigating earth systems science through the understanding of…

Thick thermal barrier coatings for diesel engines

NASA Technical Reports Server (NTRS)

Beardsley, M. Brad

1995-01-01

Caterpillar's approach to applying thick thermal barrier coatings (TTBC's) to diesel engine combustion chambers has been to use advanced modeling techniques to predict engine conditions and combine this information with fundamental property evaluation of TTBC systems to predict engine performance and TTBC stress states. Engine testing has been used to verify the predicted performance of the TTBC systems and provide information on failure mechanisms. The objective Caterpillar's program to date has been to advance the fundamental understanding of thick thermal barrier coating systems. Previous reviews of thermal barrier coating technology concluded that the current level of understanding of coating system behavior is inadequate and the lack of fundamental understanding may impeded the application of TTBC's to diesel engines. Areas of TTBC technology being examined in this program include powder characteristics and chemistry; bond coat composition; coating design, microstructure, and thickness as they affect properties, durability, and reliability; and TTBC 'aging' effects (microstructural and property changes) under diesel engine operating conditions. Methods to evaluate the reliability and durability of TTBC's have been developed that attempt to understand the fundamental strength of TTBC's for particular stress states.

Thick thermal barrier coatings for diesel engines

NASA Technical Reports Server (NTRS)

Beardsley, M. B.

1995-01-01

Caterpillar's approach to applying Thick Thermal Barrier Coatings (TTBC's) to diesel engine combustion chambers has been to use advanced modeling techniques to predict engine conditions and combine this information with fundamental property evaluation of TTBC systems to predict engine performance and TTBC stress states. Engine testing has been used to verify the predicted performance of the TTBC systems and provide information on failure mechanisms. The objective of Caterpillar's subcontract with ORNL is to advance the fundamental understanding of thick thermal barrier coating systems. Previous reviews of thermal barrier coating technology concluded that the current level of understanding of coating system behavior is inadequate and the lack of fundamental understanding may impede the application of TTBC's to diesel engines. Areas of TTBC technology being examined in this program include powder characteristics and chemistry; bond coat composition; coating design, microstructure, and thickness as they affect properties, durability, and reliability; and TTBC 'aging' effects (microstructural and property changes) under diesel engine operating conditions. Methods to evaluate the reliability and durability of TTBC's have been developed that attempt to understand the fundamental strength of TTBC's for particular stress states.

Cyber Selection Test Research Effort for U.S. Army New Accessions

DTIC Science & Technology

2017-10-12

assessment game 3. Develop an operational version of the STA game which incorporates assessments from phase 1 and (through game -play) examines...3 more STA abilities •5 STA behaviors 4. Validate the system thinking assessment game in an operational setting C O M PL ET ED PL AN N ED Research...Information Identifies Elements of Systems Models Relationships Understands System Dynamics Evaluates & Revises Model Applies Understanding to Problem STA Game

A Model to Measure Bombardier/Navigator Performance during Radar Navigation in Device 2F114, A-6E Weapon System Trainer.

DTIC Science & Technology

1981-03-01

systems, sub- systems, equipment, weapons, tactics, missions, etc. Concepts and Principles - Fundamental truths, ideas, opinions and thoughts formed from...verification, etc. Grasping the meaning of concepts and principles , i.e., understanding the basic principles of infrared and radar detection. Understanding...concepts, principles , procedures, etc.). Analysis A demonstration of a learned process of breaking down material (i.e., data, other information) into

Physics and psychophysics of color reproduction

NASA Astrophysics Data System (ADS)

Giorgianni, Edward J.

1991-08-01

The successful design of a color-imaging system requires knowledge of the factors used to produce and control color. This knowledge can be derived, in part, from measurements of the physical properties of the imaging system. Color itself, however, is a perceptual response and cannot be directly measured. Though the visual process begins with physics, as radiant energy reaching the eyes, it is in the mind of the observer that the stimuli produced from this radiant energy are interpreted and organized to form meaningful perceptions, including the perception of color. A comprehensive understanding of color reproduction, therefore, requires not only a knowledge of the physical properties of color-imaging systems but also an understanding of the physics, psychophysics, and psychology of the human observer. The human visual process is quite complex; in many ways the physical properties of color-imaging systems are easier to understand.

Systems Medicine: The Future of Medical Genomics, Healthcare, and Wellness.

PubMed

Saqi, Mansoor; Pellet, Johann; Roznovat, Irina; Mazein, Alexander; Ballereau, Stéphane; De Meulder, Bertrand; Auffray, Charles

2016-01-01

Recent advances in genomics have led to the rapid and relatively inexpensive collection of patient molecular data including multiple types of omics data. The integration of these data with clinical measurements has the potential to impact on our understanding of the molecular basis of disease and on disease management. Systems medicine is an approach to understanding disease through an integration of large patient datasets. It offers the possibility for personalized strategies for healthcare through the development of a new taxonomy of disease. Advanced computing will be an important component in effectively implementing systems medicine. In this chapter we describe three computational challenges associated with systems medicine: disease subtype discovery using integrated datasets, obtaining a mechanistic understanding of disease, and the development of an informatics platform for the mining, analysis, and visualization of data emerging from translational medicine studies.

MO-FG-207-03: Maximizing the Utility of Integrated PET/MRI in Clinical Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Behr, S.

2015-06-15

The use of integrated PET/MRI systems in clinical applications can best benefit from understanding their technological advances and limitations. The currently available clinical PET/MRI systems have their own characteristics. Thorough analyses of existing technical data and evaluation of necessary performance metrics for quality assurances could be conducted to optimize application-specific PET/MRI protocols. This Symposium will focus on technical advances and limitations of clinical PET/MRI systems, and how this exciting imaging modality can be utilized in applications that can benefit from both PET and MRI. Learning Objectives: To understand the technological advances of clinical PET/MRI systems To correctly identify clinical applicationsmore » that can benefit from PET/MRI To understand ongoing work to further improve the current PET/MRI technology Floris Jansen is a GE Healthcare employee.« less

MO-FG-207-00: Technological Advances in PET/MR Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

2015-06-15

The use of integrated PET/MRI systems in clinical applications can best benefit from understanding their technological advances and limitations. The currently available clinical PET/MRI systems have their own characteristics. Thorough analyses of existing technical data and evaluation of necessary performance metrics for quality assurances could be conducted to optimize application-specific PET/MRI protocols. This Symposium will focus on technical advances and limitations of clinical PET/MRI systems, and how this exciting imaging modality can be utilized in applications that can benefit from both PET and MRI. Learning Objectives: To understand the technological advances of clinical PET/MRI systems To correctly identify clinical applicationsmore » that can benefit from PET/MRI To understand ongoing work to further improve the current PET/MRI technology Floris Jansen is a GE Healthcare employee.« less

Understanding Microplastic Distribution: A Global Citizen Monitoring Effort

NASA Astrophysics Data System (ADS)

Barrows, A.

2016-02-01

Understanding distribution and abundance of microplastics in the world's oceans will continue to help inform global law-making. Through recruiting and training over 500 volunteers our study has collected over 1000 samples from remote and populated areas world-wide. Samples include water collected at the sea surface and throughout the water column. Surface to depth sampling has provided insight into vertical plastic distribution. The development of unique field and laboratory methodology has enabled plastics to be quantified down to 50 µm. In 2015, the study expanded to include global freshwater systems. By understanding plastic patterns, distribution and concentration in large and small watersheds we will better understand how freshwater systems are contributing to marine microplastic pollution.

Understanding Global Change: Frameworks and Models for Teaching Systems Thinking

NASA Astrophysics Data System (ADS)

Bean, J. R.; Mitchell, K.; Zoehfeld, K.; Oshry, A.; Menicucci, A. J.; White, L. D.; Marshall, C. R.

2017-12-01

The scientific and education communities must impart to teachers, students, and the public an understanding of how the various factors that drive climate and global change operate, and why the rates and magnitudes of these changes related to human perturbation of Earth system processes today are cause for deep concern. Even though effective educational modules explaining components of the Earth and climate system exist, interdisciplinary learning tools are necessary to conceptually link the causes and consequences of global changes. To address this issue, the Understanding Global Change Project at the University of California Museum of Paleontology (UCMP) at UC Berkeley developed an interdisciplinary framework that organizes global change topics into three categories: (1) causes of climate change, both human and non-human (e.g., burning of fossil fuels, deforestation, Earth's tilt and orbit), (2) Earth system processes that shape the way the Earth works (e.g., Earth's energy budget, water cycle), and (3) the measurable changes in the Earth system (e.g., temperature, precipitation, ocean acidification). To facilitate student learning about the Earth as a dynamic, interacting system, a website will provide visualizations of Earth system models and written descriptions of how each framework topic is conceptually linked to other components of the framework. These visualizations and textual summarizations of relationships and feedbacks in the Earth system are a unique and crucial contribution to science communication and education, informed by a team of interdisciplinary scientists and educators. The system models are also mechanisms by which scientists can communicate how their own work informs our understanding of the Earth system. Educators can provide context and relevancy for authentic datasets and concurrently can assess student understanding of the interconnectedness of global change phenomena. The UGC resources will be available through a web-based platform and scalable professional development programming to facilitate systemic changes in the teaching and learning about climate and global change. We are establishing a diverse community of scientists and educators across the country that are using these tools, and plan to create local networks supported by UGC staff and partners.

Information systems and human error in the lab.

PubMed

Bissell, Michael G

2004-01-01

Health system costs in clinical laboratories are incurred daily due to human error. Indeed, a major impetus for automating clinical laboratories has always been the opportunity it presents to simultaneously reduce cost and improve quality of operations by decreasing human error. But merely automating these processes is not enough. To the extent that introduction of these systems results in operators having less practice in dealing with unexpected events or becoming deskilled in problemsolving, however new kinds of error will likely appear. Clinical laboratories could potentially benefit by integrating findings on human error from modern behavioral science into their operations. Fully understanding human error requires a deep understanding of human information processing and cognition. Predicting and preventing negative consequences requires application of this understanding to laboratory operations. Although the occurrence of a particular error at a particular instant cannot be absolutely prevented, human error rates can be reduced. The following principles are key: an understanding of the process of learning in relation to error; understanding the origin of errors since this knowledge can be used to reduce their occurrence; optimal systems should be forgiving to the operator by absorbing errors, at least for a time; although much is known by industrial psychologists about how to write operating procedures and instructions in ways that reduce the probability of error, this expertise is hardly ever put to use in the laboratory; and a feedback mechanism must be designed into the system that enables the operator to recognize in real time that an error has occurred.

Impacting Early Childhood Teachers' Understanding of the Complexities of Place Value

ERIC Educational Resources Information Center

Cady, Jo Ann; Hopkins, Theresa M.; Price, Jamie

2014-01-01

In order to help children gain a more robust understanding of place value, teachers must understand the connections and relationships among the related concepts as well as possess knowledge of how children learn early number concepts. Unfortunately, teachers' familiarity with the base-ten number system and/or lack of an understanding of…

Abasy Atlas: a comprehensive inventory of systems, global network properties and systems-level elements across bacteria

PubMed Central

Ibarra-Arellano, Miguel A.; Campos-González, Adrián I.; Treviño-Quintanilla, Luis G.; Tauch, Andreas; Freyre-González, Julio A.

2016-01-01

The availability of databases electronically encoding curated regulatory networks and of high-throughput technologies and methods to discover regulatory interactions provides an invaluable source of data to understand the principles underpinning the organization and evolution of these networks responsible for cellular regulation. Nevertheless, data on these sources never goes beyond the regulon level despite the fact that regulatory networks are complex hierarchical-modular structures still challenging our understanding. This brings the necessity for an inventory of systems across a large range of organisms, a key step to rendering feasible comparative systems biology approaches. In this work, we take the first step towards a global understanding of the regulatory networks organization by making a cartography of the functional architectures of diverse bacteria. Abasy (Across-bacteria systems) Atlas provides a comprehensive inventory of annotated functional systems, global network properties and systems-level elements (global regulators, modular genes shaping functional systems, basal machinery genes and intermodular genes) predicted by the natural decomposition approach for reconstructed and meta-curated regulatory networks across a large range of bacteria, including pathogenically and biotechnologically relevant organisms. The meta-curation of regulatory datasets provides the most complete and reliable set of regulatory interactions currently available, which can even be projected into subsets by considering the force or weight of evidence supporting them or the systems that they belong to. Besides, Abasy Atlas provides data enabling large-scale comparative systems biology studies aimed at understanding the common principles and particular lifestyle adaptions of systems across bacteria. Abasy Atlas contains systems and system-level elements for 50 regulatory networks comprising 78 649 regulatory interactions covering 42 bacteria in nine taxa, containing 3708 regulons and 1776 systems. All this brings together a large corpus of data that will surely inspire studies to generate hypothesis regarding the principles governing the evolution and organization of systems and the functional architectures controlling them. Database URL: http://abasy.ccg.unam.mx PMID:27242034

Managed care: employers' influence on the health care system.

PubMed

Corder, K T; Phoon, J; Barter, M

1996-01-01

Health care reform is a complex issue involving many key sectors including providers, consumers, insurers, employers, and the government. System changes must involve all sectors for reform to be effective. Each sector has a responsibility to understand not only its own role in the health care system, but the roles of others as well. The role of business employers is often not apparent to health care providers, especially nurses. Understanding the influence employers have on the health care system is vital if providers want to be proactive change agents ensuring quality care.

Understanding pictorial information in biology: students' cognitive activities and visual reading strategies

NASA Astrophysics Data System (ADS)

Brandstetter, Miriam; Sandmann, Angela; Florian, Christine

2017-06-01

In classroom, scientific contents are increasingly communicated through visual forms of representations. Students' learning outcomes rely on their ability to read and understand pictorial information. Understanding pictorial information in biology requires cognitive effort and can be challenging to students. Yet evidence-based knowledge about students' visual reading strategies during the process of understanding pictorial information is pending. Therefore, 42 students at the age of 14-15 were asked to think aloud while trying to understand visual representations of the blood circulatory system and the patellar reflex. A category system was developed differentiating 16 categories of cognitive activities. A Principal Component Analysis revealed two underlying patterns of activities that can be interpreted as visual reading strategies: 1. Inferences predominated by using a problem-solving schema; 2. Inferences predominated by recall of prior content knowledge. Each pattern consists of a specific set of cognitive activities that reflect selection, organisation and integration of pictorial information as well as different levels of expertise. The results give detailed insights into cognitive activities of students who were required to understand the pictorial information of complex organ systems. They provide an evidence-based foundation to derive instructional aids that can promote students pictorial-information-based learning on different levels of expertise.

Global change modeling for Northern Eurasia: a review and strategies to move forward

NASA Astrophysics Data System (ADS)

Monier, E.; Kicklighter, D. W.; Sokolov, A. P.; Zhuang, Q.; Sokolik, I. N.; Lawford, R. G.; Kappas, M.; Paltsev, S.; Groisman, P. Y.

2017-12-01

Northern Eurasia is made up of a complex and diverse set of physical, ecological, climatic and human systems, which provide important ecosystem services including the storage of substantial stocks of carbon in its terrestrial ecosystems. At the same time, the region has experienced dramatic climate change, natural disturbances and changes in land management practices over the past century. For these reasons, Northern Eurasia is both a critical region to understand and a complex system with substantial challenges for the modeling community. This review is designed to highlight the state of past and ongoing efforts of the research community to understand and model these environmental, socioeconomic, and climatic changes. We further aim to provide perspectives on the future direction of global change modeling to improve our understanding of the role of Northern Eurasia in the coupled human-Earth system. Modeling efforts have shown that environmental and socioeconomic changes in Northern Eurasia can have major impacts on biodiversity, ecosystems services, environmental sustainability, and the carbon cycle of the region, and beyond. These impacts have the potential to feedback onto and alter the global Earth system. We find that past and ongoing studies have largely focused on specific components of Earth system dynamics and have not systematically examined their feedbacks to the global Earth system and to society. We identify the crucial role of Earth system models in advancing our understanding of feedbacks within the region and with the global system. We further argue for the need for integrated assessment models (IAMs), a suite of models that couple human activity models to Earth system models, which are key to address many emerging issues that require a representation of the coupled human-Earth system.

A review of and perspectives on global change modeling for Northern Eurasia

NASA Astrophysics Data System (ADS)

Monier, Erwan; Kicklighter, David W.; Sokolov, Andrei P.; Zhuang, Qianlai; Sokolik, Irina N.; Lawford, Richard; Kappas, Martin; Paltsev, Sergey V.; Groisman, Pavel Ya

2017-08-01

Northern Eurasia is made up of a complex and diverse set of physical, ecological, climatic and human systems, which provide important ecosystem services including the storage of substantial stocks of carbon in its terrestrial ecosystems. At the same time, the region has experienced dramatic climate change, natural disturbances and changes in land management practices over the past century. For these reasons, Northern Eurasia is both a critical region to understand and a complex system with substantial challenges for the modeling community. This review is designed to highlight the state of past and ongoing efforts of the research community to understand and model these environmental, socioeconomic, and climatic changes. We further aim to provide perspectives on the future direction of global change modeling to improve our understanding of the role of Northern Eurasia in the coupled human-Earth system. Modeling efforts have shown that environmental and socioeconomic changes in Northern Eurasia can have major impacts on biodiversity, ecosystems services, environmental sustainability, and the carbon cycle of the region, and beyond. These impacts have the potential to feedback onto and alter the global Earth system. We find that past and ongoing studies have largely focused on specific components of Earth system dynamics and have not systematically examined their feedbacks to the global Earth system and to society. We identify the crucial role of Earth system models in advancing our understanding of feedbacks within the region and with the global system. We further argue for the need for integrated assessment models (IAMs), a suite of models that couple human activity models to Earth system models, which are key to address many emerging issues that require a representation of the coupled human-Earth system.

Professional perspectives on systemic barriers to admission avoidance: learning from a system dynamics study of older people's admission pathways.

PubMed

Walsh, Bronagh; Lattimer, Valerie; Wintrup, Julie; Brailsford, Sally

2015-06-01

There is debate worldwide about the best way to manage increased healthcare demand within ageing populations, particularly rising rates of unplanned and avoidable hospital admissions. To understand health and social care professionals' perspectives on barriers to admission avoidance throughout the admissions journey, in particular: the causes of avoidable admissions in older people; drivers of admission and barriers to use of admission avoidance strategies; and improvements to reduce unnecessary admissions. A qualitative framework analysis of interview data from a System dynamics (SD) modelling study. Semi-structured interviews were conducted with twenty health and social care professionals with experience of older people's admissions. The interviews were used to build understanding of factors facilitating or hindering admission avoidance across the admissions system. Data were analysed using framework analysis. Three overarching themes emerged: understanding the needs of the patient group; understanding the whole system; and systemwide access to expertise in care of older people. There were diverse views on the underlying reasons for avoidable admissions and recognition of the need for whole-system approaches to service redesign. Participants recommended system redesign that recognises the specific needs of older people, but there was no consensus on underlying patient needs or specific service developments. Access to expertise in management of older and frailer patients was seen as a barrier to admission avoidance throughout the system. Providing access to expertise and leadership in care of frail older people across the admissions system presents a challenge for service managers and nurse educators but is seen as a prerequisite for effective admission avoidance. System redesign to meet the needs of frail older people requires agreement on causes of avoidable admission and underlying patient needs. © 2014 John Wiley & Sons Ltd.

Autonomous Attitude Determination System (AADS). Volume 1: System description

NASA Technical Reports Server (NTRS)

Saralkar, K.; Frenkel, Y.; Klitsch, G.; Liu, K. S.; Lefferts, E.; Tasaki, K.; Snow, F.; Garrahan, J.

1982-01-01

Information necessary to understand the Autonomous Attitude Determination System (AADS) is presented. Topics include AADS requirements, program structure, algorithms, and system generation and execution.

Planetary Migration and Kuiper Belt Dynamics

NASA Astrophysics Data System (ADS)

Malhotra, Renu

The Kuiper belt holds memory of the dynamical processes that shaped the architecture of the solar system, including the orbital migration history of the giant planets. We propose studies of the orbital dynamics of the Kuiper Belt in order to understand the origin of its complex dynamical structure and its link to the orbital migration history of the giant planets. By means of numerical simulations, statistical tests, as well as analytical calculations we will (1) investigate the origin of resonant Kuiper belt objects to test alternative scenarios of Neptune's migration history, (2) investigate the long term dynamical evolution of the Haumea family of Kuiper Belt objects in order to improve the age estimate of this family, and (3) investigate resonance-sticking behavior and the Kozai-Lidov mechanism and its role in the origin of the extended scattered disk. These studies directly support the goals of the NASA-OSS program by improving our understanding of the origin of the solar system's architecture. Our results will provide constraints on the nature and timing of the dynamical excitation event that is thought to have occurred in early solar system history and to have determined the architecture of the present-day solar system; our results will also provide deeper theoretical understanding of sticky mean motion resonances which contribute greatly to the longevity of many small bodies, improve our understanding of dynamical transport of planetesimals in planetary systems, and help interpret observations of other planetary systems.

Comparison of Students' Understanding of Functions in Classes Following English and Israeli National Curricula

ERIC Educational Resources Information Center

Watson, Anne; Ayalon, Michal; Lerman, Stephen

2018-01-01

This paper arises from a study of how concepts related to understanding functions develop for students across the years of secondary/high school, using small samples from two different curricula systems: England and Israel. We used a survey consisting of function tasks developed in collaboration with teachers from both curriculum systems. We…

A World-System Approach to Post-Catastrophe International Relief

ERIC Educational Resources Information Center

Letukas, Lynn; Barnshaw, John

2008-01-01

As our understanding of disaster shifts from an event concentrated in time and space to a social occasion occurring across time and space, so too must our explanations of disaster shift from theories of the middle range to broader theoretical frameworks. We explore the world-system approach in an effort to understand the upper limits of theory for…

Why Don't Well-Educated Adults Understand Accumulation? A Challenge to Researchers, Educators, and Citizens

ERIC Educational Resources Information Center

Cronin, Matthew A.; Gonzalez, Cleotilde; Sterman, John D.

2009-01-01

Accumulation is a fundamental process in dynamic systems: inventory accumulates production less shipments; the national debt accumulates the federal deficit. Effective decision making in such systems requires an understanding of the relationship between stocks and the flows that alter them. However, highly educated people are often unable to infer…

The Role of Organizational Context and External Influences in the Implementation of Evidence-Based Programs: An Exploratory Study. Report IV

ERIC Educational Resources Information Center

Collins, Ashleigh; Burkhauser, Mary

2008-01-01

The implementation of high-quality evidence-based practices cannot occur without facilitative administration, systems-level partnerships, and decision-support data systems. The authors believe that understanding "what works" in program "implementation" is just as important as understanding "what works" in a program "model." Recently, researchers…

Farm to Table and beyond: Helping Students Make Sense of the Global Food System

ERIC Educational Resources Information Center

Koch, Pamela; Barton, Angela Calabrese; Contento, Isobel; Crabtree, Margo

2008-01-01

It is not enough for students to acquire knowledge about how food is produced and processed; they must also come to understand the biological and environmental contexts in which food production, processing, and transportation take place. Through diagramming, students begin to understand that our food system has a series of interacting parts and…

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT XXI, MICHIGAN/CLARK TRANSMISSION--COMPLETE POWER TRAIN.

ERIC Educational Resources Information Center

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MOSULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF A SPECIFIC POWER TRAIN SYSTEM USED ON DIESEL POWERED EQUIPMENT. TOPICS ARE EXAMINING THE POWER FLOW, UNIT OIL FLOW, AND OIL PRESSURE IN THE CONVERTER AND TRANSMISSION SYSTEM. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL PROGRAM TRAINING FILM "UNDERSTANDING THE…

Action Learning for Organizational and Systemic Development: Towards a "Both-and" Understanding of "I" and "We"

ERIC Educational Resources Information Center

Rigg, Clare

2008-01-01

In public services delivery, action learning is increasingly employed in the hope of improving capacity to address complex, multi-casual and "wicked" social issues to improve the lives of citizens. Yet the understanding of how and why action learning might have potential for enhancing organizational or systemic capability rarely goes…

Understanding Ionic Bonding--A Scan across the Croatian Education System

ERIC Educational Resources Information Center

Vladušic, R.; Bucat, R. B.; Ožic, M.

2016-01-01

A study was conducted on the understandings of the accepted model of ionic substances that are held by participants at all levels of the chemical education system in Croatia, including secondary school students, university students, and chemistry teachers. We follow the research of Taber who found that a diagram of a layer of a sodium chloride…

Understanding Learner Agency as a Complex Dynamic System

ERIC Educational Resources Information Center

Mercer, Sarah

2011-01-01

This paper attempts to contribute to a fuller understanding of the nature of language learner agency by considering it as a complex dynamic system. The purpose of the study was to explore detailed situated data to examine to what extent it is feasible to view learner agency through the lens of complexity theory. Data were generated through a…

Illustrative Memorandum of Understanding: Between a Public Institution or System and an Affiliated Foundation

ERIC Educational Resources Information Center

Association of Governing Boards of Universities and Colleges, 2014

2014-01-01

A decade ago, the Association of Governing Boards of Universities and Colleges (AGB) and the Council for Advancement and Support of Education (CASE), working with a national task force, developed an illustrative memorandum of understanding (MOU) that was widely promulgated and served as a model for agreements at many institutions and systems. This…

Scientific Models Help Students Understand the Water Cycle

ERIC Educational Resources Information Center

Forbes, Cory; Vo, Tina; Zangori, Laura; Schwarz, Christina

2015-01-01

The water cycle is a large, complex system that encompasses ideas across the K-12 science curriculum. By the time students leave fifth grade, they should understand "that a system is a group of related parts that make up a whole and can carry out functions its individual parts cannot" and be able to describe both components and processes…

Fundamental research on spiking, recovery and understanding seed coat nep counts in AFIS analysis of pre-opened cotton

USDA-ARS?s Scientific Manuscript database

Understanding seed coat fragment (SCF) spiking results in Advanced Fiber Information Systems (AFIS) analysis of seed coat neps (SCN) in ginned cottons was confounded by side processes in the system such as particle crushing that results in inflated recoveries. A high degree of machine (AFIS)-fiber ...

Meaningful Understanding and Systems Thinking in Organic Chemistry: Validating Measurement and Exploring Relationships

ERIC Educational Resources Information Center

Vachliotis, Theodoros; Salta, Katerina; Tzougraki, Chryssa

2014-01-01

The purpose of this study was dual: First, to develop and validate assessment schemes for assessing 11th grade students' meaningful understanding of organic chemistry concepts, as well as their systems thinking skills in the domain. Second, to explore the relationship between the two constructs of interest based on students' performance…

The Virtual Solar System Project: Developing Conceptual Understanding of Astronomical Concepts through Building Three-Dimensional Computational Models.

ERIC Educational Resources Information Center

Keating, Thomas; Barnett, Michael; Barab, Sasha A.; Hay, Kenneth E.

2002-01-01

Describes the Virtual Solar System (VSS) course which is one of the first attempts to integrate three-dimensional (3-D) computer modeling as a central component of introductory undergraduate education. Assesses changes in student understanding of astronomy concepts as a result of participating in an experimental introductory astronomy course in…

Reliability achievement in high technology space systems

NASA Technical Reports Server (NTRS)

Lindstrom, D. L.

1981-01-01

The production of failure-free hardware is discussed. The elements required to achieve such hardware are: technical expertise to design, analyze, and fully understand the design; use of high reliability parts and materials control in the manufacturing process; and testing to understand the system and weed out defects. The durability of the Hughes family of satellites is highlighted.

48 CFR 1552.215-74 - Advanced understanding-uncompensated time.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Advanced understanding... Clauses 1552.215-74 Advanced understanding—uncompensated time. As prescribed in 1515.408(b), insert the following provision or one substantially the same as the following provision: Advanced Understanding...

ARITHMETIC PROGRAM FOURTH YEAR.

ERIC Educational Resources Information Center

GARBER, CLAIRE N.

THE 4TH YEAR SHOULD CONTINUE THE SEQUENTIAL PRESENTATION MATHEMATICAL UNDERSTANDINGS AND RELATIONSHIPS. NEW LEARNINGS SHOULD BE PRESENTED CONCRETELY IN SOCIAL SETTINGS WITHIN THE CHILDREN'S FRAMEWORK OF UNDERSTANDING. GRAPHIC MATERIALS MAY BE USED TO BRIDGE THE UNDERSTANDINGS FROM THE CONCRETE TO THE ABSTRACT LEVEL. THE NUMBER SYSTEM UNIT SHOULD…

Characteristics, processes, and causes of the spatio-temporal variabilities of the East Asian monsoon system

NASA Astrophysics Data System (ADS)

Huang, Ronghui; Chen, Jilong; Wang, Lin; Lin, Zhongda

2012-09-01

Recent advances in the study of the characteristics, processes, and causes of spatio-temporal variabilities of the East Asian monsoon (EAM) system are reviewed in this paper. The understanding of the EAM system has improved in many aspects: the basic characteristics of horizontal and vertical structures, the annual cycle of the East Asian summer monsoon (EASM) system and the East Asian winter monsoon (EAWM) system, the characteristics of the spatio-temporal variabilities of the EASM system and the EAWM system, and especially the multiple modes of the EAM system and their spatio-temporal variabilities. Some new results have also been achieved in understanding the atmosphere-ocean interaction and atmosphere-land interaction processes that affect the variability of the EAM system. Based on recent studies, the EAM system can be seen as more than a circulation system, it can be viewed as an atmosphere-ocean-land coupled system, namely, the EAM climate system. In addition, further progress has been made in diagnosing the internal physical mechanisms of EAM climate system variability, especially regarding the characteristics and properties of the East Asia-Pacific (EAP) teleconnection over East Asia and the North Pacific, the "Silk Road" teleconnection along the westerly jet stream in the upper troposphere over the Asian continent, and the dynamical effects of quasi-stationary planetary wave activity on EAM system variability. At the end of the paper, some scientific problems regarding understanding the EAM system variability are proposed for further study.

Systems biology: the case for a systems science approach to diabetes.

PubMed

Petrasek, Danny

2008-01-01

The unprecedented accumulation of biological data in recent decades has underscored the need to organize and integrate the massive collection of information. In addition, there is rising agreement among biologists that a complete understanding of a single cell will not lead directly to a complete understanding of a system of cells. The success of a systems science approach in engineering and physics may be of great value in the evolution of biological science. This article reviews some examples that suggest the importance of a systems biology approach and, in addition, advance one specific systems science principle, the conservation of uncertainty, which may give insight into the emergent behavior of numerous biological and physiological phenomena.

Global Night-Time Lights for Observing Human Activity

NASA Technical Reports Server (NTRS)

Hipskind, Stephen R.; Elvidge, Chris; Gurney, K.; Imhoff, Mark; Bounoua, Lahouari; Sheffner, Edwin; Nemani, Ramakrishna R.; Pettit, Donald R.; Fischer, Marc

2011-01-01

We present a concept for a small satellite mission to make systematic, global observations of night-time lights with spatial resolution suitable for discerning the extent, type and density of human settlements. The observations will also allow better understanding of fine scale fossil fuel CO2 emission distribution. The NASA Earth Science Decadal Survey recommends more focus on direct observations of human influence on the Earth system. The most dramatic and compelling observations of human presence on the Earth are the night light observations taken by the Defence Meteorological System Program (DMSP) Operational Linescan System (OLS). Beyond delineating the footprint of human presence, night light data, when assembled and evaluated with complementary data sets, can determine the fine scale spatial distribution of global fossil fuel CO2 emissions. Understanding fossil fuel carbon emissions is critical to understanding the entire carbon cycle, and especially the carbon exchange between terrestrial and oceanic systems.

Getting the lead out: understanding risks in the distribution ...

EPA Pesticide Factsheets

This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap. Invited presentation on topics indicated as of interest. With exposure to lead as the context, this presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap.

Techniques for Fault Detection and Visualization of Telemetry Dependence Relationships for Root Cause Fault Analysis in Complex Systems

NASA Astrophysics Data System (ADS)

Guy, Nathaniel

This thesis explores new ways of looking at telemetry data, from a time-correlative perspective, in order to see patterns within the data that may suggest root causes of system faults. It was thought initially that visualizing an animated Pearson Correlation Coefficient (PCC) matrix for telemetry channels would be sufficient to give new understanding; however, testing showed that the high dimensionality and inability to easily look at change over time in this approach impeded understanding. Different correlative techniques, combined with the time curve visualization proposed by Bach et al (2015), were adapted to visualize both raw telemetry and telemetry data correlations. Review revealed that these new techniques give insights into the data, and an intuitive grasp of data families, which show the effectiveness of this approach for enhancing system understanding and assisting with root cause analysis for complex aerospace systems.

Toward a theory of punctuated subsistence change.

PubMed

Ullah, Isaac I T; Kuijt, Ian; Freeman, Jacob

2015-08-04

Discourse on the origins and spread of domesticated species focuses on universal causal explanations or unique regional or temporal trajectories. Despite new data as to the context and physical processes of early domestication, researchers still do not understand the types of system-level reorganizations required to transition from foraging to farming. Drawing upon dynamical systems theory and the concepts of attractors and repellors, we develop an understanding of subsistence transition and a description of variation in, and emergence of, human subsistence systems. The overlooked role of attractors and repellors in these systems helps explain why the origins of agriculture occurred quickly in some times and places, but slowly in others. A deeper understanding of the interactions of a limited set of variables that control the size of attractors (a proxy for resilience), such as population size, number of dry months, net primary productivity, and settlement fixity, provides new insights into the origin and spread of domesticated species in human economies.

Network information analysis reveals risk perception transmission in a behaviour-influenza dynamics system.

PubMed

Liao, C-M; You, S-H; Cheng, Y-H

2015-01-01

Influenza poses a significant public health burden worldwide. Understanding how and to what extent people would change their behaviour in response to influenza outbreaks is critical for formulating public health policies. We incorporated the information-theoretic framework into a behaviour-influenza (BI) transmission dynamics system in order to understand the effects of individual behavioural change on influenza epidemics. We showed that information transmission of risk perception played a crucial role in the spread of health-seeking behaviour throughout influenza epidemics. Here a network BI model provides a new approach for understanding the risk perception spread and human behavioural change during disease outbreaks. Our study allows simultaneous consideration of epidemiological, psychological, and social factors as predictors of individual perception rates in behaviour-disease transmission systems. We suggest that a monitoring system with precise information on risk perception should be constructed to effectively promote health behaviours in preparation for emerging disease outbreaks.

Video Analysis and Remote Digital Ethnography: Approaches to understanding user perspectives and processes involving healthcare information technology.

PubMed

Kushniruk, Andre W; Borycki, Elizabeth M

2015-01-01

Innovations in healthcare information systems promise to revolutionize and streamline healthcare processes worldwide. However, the complexity of these systems and the need to better understand issues related to human-computer interaction have slowed progress in this area. In this chapter the authors describe their work in using methods adapted from usability engineering, video ethnography and analysis of digital log files for improving our understanding of complex real-world healthcare interactions between humans and technology. The approaches taken are cost-effective and practical and can provide detailed ethnographic data on issues health professionals and consumers encounter while using systems as well as potential safety problems. The work is important in that it can be used in techno-anthropology to characterize complex user interactions with technologies and also to provide feedback into redesign and optimization of improved healthcare information systems.

MO-FG-207-01: Technological Advances and Challenges: Experience with the First Integrated Whole-Body PET/MRI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laforest, R.

2015-06-15

The use of integrated PET/MRI systems in clinical applications can best benefit from understanding their technological advances and limitations. The currently available clinical PET/MRI systems have their own characteristics. Thorough analyses of existing technical data and evaluation of necessary performance metrics for quality assurances could be conducted to optimize application-specific PET/MRI protocols. This Symposium will focus on technical advances and limitations of clinical PET/MRI systems, and how this exciting imaging modality can be utilized in applications that can benefit from both PET and MRI. Learning Objectives: To understand the technological advances of clinical PET/MRI systems To correctly identify clinical applicationsmore » that can benefit from PET/MRI To understand ongoing work to further improve the current PET/MRI technology Floris Jansen is a GE Healthcare employee.« less

System-level musings about system-level science (Invited)

NASA Astrophysics Data System (ADS)

Liu, W.

2009-12-01

In teleology, a system has a purpose. In physics, a system has a tendency. For example, a mechanical system has a tendency to lower its potential energy. A thermodynamic system has a tendency to increase its entropy. Therefore, if geospace is seen as a system, what is its tendency? Surprisingly or not, there is no simple answer to this question. Or, to flip the statement, the answer is complex, or complexity. We can understand generally why complexity arises, as the geospace boundary is open to influences from the solar wind and Earth’s atmosphere and components of the system couple to each other in a myriad of ways to make the systemic behavior highly nonlinear. But this still begs the question: What is the system-level approach to geospace science? A reductionist view might assert that as our understanding of a component or subsystem progresses to a certain point, we can couple some together to understand the system on a higher level. However, in practice, a subsystem can almost never been observed in isolation with others. Even if such is possible, there is no guarantee that the subsystem behavior will not change when coupled to others. Hence, there is no guarantee that a subsystem, such as the ring current, has an innate and intrinsic behavior like a hydrogen atom. An absolutist conclusion from this logic can be sobering, as one would have to trace a flash of aurora to the nucleosynthesis in the solar core. The practical answer, however, is more promising; it is a mix of the common sense we call reductionism and awareness that, especially when strongly coupled, subsystems can experience behavioral changes, breakdowns, and catastrophes. If the stock answer to the systemic tendency of geospace is complexity, the objective of the system-level approach to geospace science is to define, measure, and understand this complexity. I will use the example of magnetotail dynamics to illuminate some key points in this talk.

Health Belief Systems and the Psychobiology of War

PubMed Central

Elgee, Neil J.

1984-01-01

Belief systems overlie powerful biological and psychological forces that are root causes of war. Much as in medicine where an appreciation of health belief systems is necessary in the control of illness and disease, so the paths to the control of war may lie in an understanding of belief systems and ways to circumvent them. Such understanding gives strong theoretical support to many time-honored but underutilized international initiative and educational ventures. The effort of the medical community to educate the public about biomedical aspects of nuclear war should gain more balance and sophistication with an appreciation of belief systems in the psychobiology of war. PMID:6741137

Systems Thinking to Improve the Public’s Health

PubMed Central

Leischow, Scott J.; Best, Allan; Trochim, William M.; Clark, Pamela I.; Gallagher, Richard S.; Marcus, Stephen E.; Matthews, Eva

2014-01-01

Improving population health requires understanding and changing societal structures and functions, but countervailing forces sometimes undermine those changes, thus reflecting the adaptive complexity inherent in public health systems. The purpose of this paper is to propose systems thinking as a conceptual rubric for the practice of team science in public health, and transdisciplinary, translational research as a catalyst for promoting the functional efficiency of science. The paper lays a foundation for the conceptual understanding of systems thinking and transdisciplinary research, and will provide illustrative examples within and beyond public health. A set of recommendations for a systems-centric approach to translational science will be presented. PMID:18619400

Synthetic biology through biomolecular design and engineering.

PubMed

Channon, Kevin; Bromley, Elizabeth H C; Woolfson, Derek N

2008-08-01

Synthetic biology is a rapidly growing field that has emerged in a global, multidisciplinary effort among biologists, chemists, engineers, physicists, and mathematicians. Broadly, the field has two complementary goals: To improve understanding of biological systems through mimicry and to produce bio-orthogonal systems with new functions. Here we review the area specifically with reference to the concept of synthetic biology space, that is, a hierarchy of components for, and approaches to generating new synthetic and functional systems to test, advance, and apply our understanding of biological systems. In keeping with this issue of Current Opinion in Structural Biology, we focus largely on the design and engineering of biomolecule-based components and systems.

Planetary Rings

NASA Astrophysics Data System (ADS)

Gordon, M. K.; Araki, S.; Black, G. J.; Bosh, A. S.; Brahic, A.; Brooks, S. M.; Charnoz, S.; Colwell, J. E.; Cuzzi, J. N.; Dones, L.; Durisen, R. H.; Esposito, L. W.; Ferrari, C.; Festou, M.; French, R. G.; Giuliatti-Winter, S. M.; Graps, A. L.; Hamilton, D. P.; Horanyi, M.; Karjalainen, R. M.; Krivov, A. V.; Krueger, H.; Larson, S. M.; Levison, H. F.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Namouni, F.; Nicholson, P. D.; Olkin, C. B.; Poulet, F.; Rappaport, N. J.; Salo, H. J.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Stewart, G. R.; Yanamandra-Fisher, P.

2002-08-01

The past two decades have witnessed dramatic changes in our view and understanding of planetary rings. We now know that each of the giant planets in the Solar System possesses a complex and unique ring system. Recent studies have identified complex gravitational interactions between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto, or collisions between, parent bodies. Yet, as far as we have come, our understanding is far from complete. The fundamental questions confronting ring scientists at the beginning of the twenty-first century are those regarding the origin, age and evolution of the various ring systems, in the broadest context. Understanding the origin and age requires us to know the current ring properties, and to understand the dominant evolutionary processes and how they influence ring properties. Here we discuss a prioritized list of the key questions, the answers to which would provide the greatest improvement in our understanding of planetary rings. We then outline the initiatives, missions, and other supporting activities needed to address those questions, and recommend priorities for the coming decade in planetary ring science.

Intent inferencing with a model-based operator's associate

NASA Technical Reports Server (NTRS)

Jones, Patricia M.; Mitchell, Christine M.; Rubin, Kenneth S.

1989-01-01

A portion of the Operator Function Model Expert System (OFMspert) research project is described. OFMspert is an architecture for an intelligent operator's associate or assistant that can aid the human operator of a complex, dynamic system. Intelligent aiding requires both understanding and control. The understanding (i.e., intent inferencing) ability of the operator's associate is discussed. Understanding or intent inferencing requires a model of the human operator; the usefulness of an intelligent aid depends directly on the fidelity and completeness of its underlying model. The model chosen for this research is the operator function model (OFM). The OFM represents operator functions, subfunctions, tasks, and actions as a heterarchic-hierarchic network of finite state automata, where the arcs in the network are system triggering events. The OFM provides the structure for intent inferencing in that operator functions and subfunctions correspond to likely operator goals and plans. A blackboard system similar to that of Human Associative Processor (HASP) is proposed as the implementation of intent inferencing function. This system postulates operator intentions based on current system state and attempts to interpret observed operator actions in light of these hypothesized intentions.

Real-Time Visualization of Network Behaviors for Situational Awareness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Best, Daniel M.; Bohn, Shawn J.; Love, Douglas V.

Plentiful, complex, and dynamic data make understanding the state of an enterprise network difficult. Although visualization can help analysts understand baseline behaviors in network traffic and identify off-normal events, visual analysis systems often do not scale well to operational data volumes (in the hundreds of millions to billions of transactions per day) nor to analysis of emergent trends in real-time data. We present a system that combines multiple, complementary visualization techniques coupled with in-stream analytics, behavioral modeling of network actors, and a high-throughput processing platform called MeDICi. This system provides situational understanding of real-time network activity to help analysts takemore » proactive response steps. We have developed these techniques using requirements gathered from the government users for which the tools are being developed. By linking multiple visualization tools to a streaming analytic pipeline, and designing each tool to support a particular kind of analysis (from high-level awareness to detailed investigation), analysts can understand the behavior of a network across multiple levels of abstraction.« less

Sustainability or collapse: what can we learn from integrating the history of humans and the rest of nature?

PubMed

Costanza, Robert; Graumlich, Lisa; Steffen, Will; Crumley, Carole; Dearing, John; Hibbard, Kathy; Leemans, Rik; Redman, Charles; Schimel, David

2007-11-01

Understanding the history of how humans have interacted with the rest of nature can help clarify the options for managing our increasingly interconnected global system. Simple, deterministic relationships between environmental stress and social change are inadequate. Extreme drought, for instance, triggered both social collapse and ingenious management of water through irrigation. Human responses to change, in turn, feed into climate and ecological systems, producing a complex web of multidirectional connections in time and space. Integrated records of the co-evolving human-environment system over millennia are needed to provide a basis for a deeper understanding of the present and for forecasting the future. This requires the major task of assembling and integrating regional and global historical, archaeological, and paleoenvironmental records. Humans cannot predict the future. But, if we can adequately understand the past, we can use that understanding to influence our decisions and to create a better, more sustainable and desirable future.

Modeling Complex Cross-Systems Software Interfaces Using SysML

NASA Technical Reports Server (NTRS)

Mandutianu, Sanda; Morillo, Ron; Simpson, Kim; Liepack, Otfrid; Bonanne, Kevin

2013-01-01

The complex flight and ground systems for NASA human space exploration are designed, built, operated and managed as separate programs and projects. However, each system relies on one or more of the other systems in order to accomplish specific mission objectives, creating a complex, tightly coupled architecture. Thus, there is a fundamental need to understand how each system interacts with the other. To determine if a model-based system engineering approach could be utilized to assist with understanding the complex system interactions, the NASA Engineering and Safety Center (NESC) sponsored a task to develop an approach for performing cross-system behavior modeling. This paper presents the results of applying Model Based Systems Engineering (MBSE) principles using the System Modeling Language (SysML) to define cross-system behaviors and how they map to crosssystem software interfaces documented in system-level Interface Control Documents (ICDs).

Learning immunology from the yellow fever vaccine: innate immunity to systems vaccinology.

PubMed

Pulendran, Bali

2009-10-01

Despite their great success, we understand little about how effective vaccines stimulate protective immune responses. Two recent developments promise to yield such understanding: the appreciation of the crucial role of the innate immune system in sensing microorganisms and tuning immune responses, and advances in systems biology. Here I review how these developments are yielding insights into the mechanism of action of the yellow fever vaccine, one of the most successful vaccines ever developed, and the broader implications for vaccinology.

FAST Modularization Framework for Wind Turbine Simulation: Full-System Linearization

DOE PAGES

Jonkman, Jason M.; Jonkman, Bonnie J.

2016-10-03

The wind engineering community relies on multiphysics engineering software to run nonlinear time-domain simulations e.g. for design-standards-based loads analysis. Although most physics involved in wind energy are nonlinear, linearization of the underlying nonlinear system equations is often advantageous to understand the system response and exploit well-established methods and tools for analyzing linear systems. Here, this paper presents the development and verification of the new linearization functionality of the open-source engineering tool FAST v8 for land-based wind turbines, as well as the concepts and mathematical background needed to understand and apply it correctly.

FAST modularization framework for wind turbine simulation: full-system linearization

NASA Astrophysics Data System (ADS)

Jonkman, J. M.; Jonkman, B. J.

2016-09-01

The wind engineering community relies on multiphysics engineering software to run nonlinear time-domain simulations e.g. for design-standards-based loads analysis. Although most physics involved in wind energy are nonlinear, linearization of the underlying nonlinear system equations is often advantageous to understand the system response and exploit well- established methods and tools for analyzing linear systems. This paper presents the development and verification of the new linearization functionality of the open-source engineering tool FAST v8 for land-based wind turbines, as well as the concepts and mathematical background needed to understand and apply it correctly.

Discussion of "Representation of People's Decisions in Health Information Systems: A Complementary Approach for Understanding Health Care Systems and Population Health".

PubMed

Al-Shorbaji, Najeeb; Borycki, Elizabeth M; Kimura, Michio; Lehmann, Christoph U; Lorenzi, Nancy M; Moura, Lincoln A; Winter, Alfred

2017-02-01

This article is part of a For-Discussion-Section of Methods of Information in Medicine about the paper "Representation of People's Decisions in Health Information Systems: A Complementary Approach for Understanding Health Care Systems and Population Health" written by Fernan Gonzalez Bernaldo de Quiros, Adriana Ruth Dawidowski, and Silvana Figar. It is introduced by an editorial. This article contains the combined commentaries invited to independently comment on the paper of de Quiros, Dawidowski, and Figar. In subsequent issues the discussion can continue through letters to the editor.

Student Teachers' Ways of Thinking and Ways of Understanding Digestion and the Digestive System in Biology

ERIC Educational Resources Information Center

Çimer, Sabiha Odabasi; Ursavas, Nazihan

2012-01-01

The purpose of this study was to identify the ways in which student teachers understand digestion and the digestive system and, subsequently, their ways of thinking, as reflected in their problem solving approaches and the justification schemes that they used to validate their claims. For this purpose, clinical interviews were conducted with 10…

Making a Map of Science: General Systems Theory as a Conceptual Framework for Tertiary Science Education.

ERIC Educational Resources Information Center

Gulyaev, Sergei A.; Stonyer, Heather R.

2002-01-01

Develops an integrated approach based on the use of general systems theory (GST) and the concept of 'mapping' scientific knowledge to provide students with tools for a more holistic understanding of science. Uses GST as the core methodology for understanding science and its complexity. Discusses the role of scientific community in producing…

The "Life at the Poles" Study Unit: Developing Junior High School Students' Ability to Recognize the Relations between Earth Systems

ERIC Educational Resources Information Center

Assaraf, Orit Ben-Zvi; Orpaz, Idit

2010-01-01

Understanding of Earth's systems, including the crucial role of human beings within them, is an important part of citizens' ability to think intelligently and critically about the environment, pollution, sustainability and other socio-economic and scientific issues central to life in the modern world. Part of this understanding involves seeing the…

Design Experiments: Developing and Testing an Intervention for Elementary School-Age Students Who Use Non-Mainstream American English Dialects

ERIC Educational Resources Information Center

Thomas-Tate, Shurita; Connor, Carol McDonald; Johnson, Lakeisha

2013-01-01

Reading comprehension, defined as the active extraction and construction of meaning from all kinds of text, requires children to fluently decode and understand what they are reading. Basic processes underlying reading comprehension are complex and call on the oral language system and a conscious understanding of this system, i.e., metalinguistic…

Undergraduate Students' Mental Models of the Climate System

ERIC Educational Resources Information Center

Mehta, Jignesh

2017-01-01

The climate, being a complex system, is difficult for people to understand. If better education is to be designed to improve the public's understanding of the subject, educators must be aware of the prior knowledge that students bring with them to the classroom since it is through that prism that people make sense of the world. As such, the aim of…

Lessons Learned in Systemic District Reform: A Cross-District Analysis from the Comprehensive Aligned Instructional System (CAIS) Benchmarking Study

ERIC Educational Resources Information Center

Waters, Louise Bay; Vargo, Merrill

2008-01-01

Urban district reform has been hampered by the challenge of understanding and supporting the tremendous complexity of district change. Improving this understanding through actionable, practice-based research is the purpose of this study. The authors began the study with the hypothesis that achieving districts both align their instructional systems…

Progress report on understanding AFIS seed coat nep levels in pre-opened slivers on the Advanced Fiber Information System (AFIS)

USDA-ARS?s Scientific Manuscript database

The Advanced Fiber Information System (AFIS) is utilized in this segment of the research project to study how seed coat neps are measured. A patent search was conducted, and studied to assist with the understanding of the AFIS measurement of this impurity in raw cotton. The older AFIS 2 is primari...

Towards an Analytical Framework for Understanding the Development of a Quality Assurance System in an International Joint Programme

ERIC Educational Resources Information Center

Zheng, Gaoming; Cai, Yuzhuo; Ma, Shaozhuang

2017-01-01

This paper intends to construct an analytical framework for understanding quality assurance in international joint programmes and to test it in a case analysis of a European--Chinese joint doctoral degree programme. The development of a quality assurance system for an international joint programme is understood as an institutionalization process…

"Toward High School Biology": Helping Middle School Students Understand Chemical Reactions and Conservation of Mass in Nonliving and Living Systems

ERIC Educational Resources Information Center

Herrmann-Abell, Cari F.; Koppal, Mary; Roseman, Jo Ellen

2016-01-01

Modern biology has become increasingly molecular in nature, requiring students to understand basic chemical concepts. Studies show, however, that many students fail to grasp ideas about atom rearrangement and conservation during chemical reactions or the application of these ideas to biological systems. To help provide students with a better…

Developing a Deeper Understanding of "Mathematics Teaching Expertise": An Examination of Three Chinese Mathematics Teachers' Resource Systems as Windows into Their Work and Expertise

ERIC Educational Resources Information Center

Pepin, Birgit; Xu, Binyan; Trouche, Luc; Wang, Chongyang

2017-01-01

In order to develop a deeper understanding of mathematics teaching expertise, in this study we use the Documentational Approach to Didactics to explore the resource systems of three Chinese mathematics "expert" teachers. Exploiting the Western and Eastern literature we examine the notion of "mathematics teaching expertise", as…

Robotics and Science Literacy: Thinking Skills, Science Process Skills and Systems Understanding

ERIC Educational Resources Information Center

Sullivan, Florence R.

2008-01-01

This paper reports the results of a study of the relationship of robotics activity to the use of science literacy skills and the development of systems understanding in middle school students. Twenty-six 11-12-year-olds (22 males and 4 females) attending an intensive robotics course offered at a summer camp for academically advanced students…

Revisiting the Blended Learning Literature: Using a Complex Adaptive Systems Framework

ERIC Educational Resources Information Center

Wang, Yuping; Han, Xibin; Yang, Juan

2015-01-01

This research has two aims: (1) to bridge a gap in blended learning research--the lack of a systems approach to the understanding of blended learning research and practice, and (2) to promote a more comprehensive understanding of what has been achieved and what needs to be achieved in blended learning research and practice. To achieve these aims,…

Native American Students' Understanding of Geologic Time Scale: 4th-8th Grade Ojibwe Students' Understanding of Earth's Geologic History

ERIC Educational Resources Information Center

Nam, Younkyeong; Karahan, Engin; Roehrig, Gillian

2016-01-01

Geologic time scale is a very important concept for understanding long-term earth system events such as climate change. This study examines forty-three 4th-8th grade Native American--particularly Ojibwe tribe--students' understanding of relative ordering and absolute time of Earth's significant geological and biological events. This study also…

Does Climate Care about Land?

NASA Astrophysics Data System (ADS)

Dawson, E.; Lague, M. M.; Swann, A. L. S.

2017-12-01

Everyone knows that plants are influenced by the climate they live in. However, the reverse is also true: plants can influence climate both locally and globally by changing atmospheric circulation. Uncovering the role that plants play in climate has been challenging—the interactions are complex and vary greatly in different regions of the world. We lack a systematic understanding of the role of vegetation in the climate system. Using a new simplified land model coupled to a modern Earth System Model (ESM), we are able to separate the individual influences of the land system in the context of modern ESMs. For example, with our model we are able to test how the capacity of the land to hold water influences the atmosphere. If less water is able to evaporate, this could lead to substantial warming, and could even influence clouds. Understanding specifically where and how the atmosphere is influenced by the land surface improves our understanding of how future changes in the land surface will in turn feedback on climate, and how that will impact people. This improved understanding also advances our knowledge of the key role biology plays in driving the global climate system.

Insights from Modeling the Integrated Climate, Biogeochemical Cycles, Human Activities and Their Interactions in the ACME Earth System Model

NASA Astrophysics Data System (ADS)

Leung, L. R.; Thornton, P. E.; Riley, W. J.; Calvin, K. V.

2017-12-01

Towards the goal of understanding the contributions from natural and managed systems to current and future greenhouse gas fluxes and carbon-climate and carbon-CO2 feedbacks, efforts have been underway to improve representations of the terrestrial, river, and human components of the ACME earth system model. Broadly, our efforts include implementation and comparison of approaches to represent the nutrient cycles and nutrient limitations on ecosystem production, extending the river transport model to represent sediment and riverine biogeochemistry, and coupling of human systems such as irrigation, reservoir operations, and energy and land use with the ACME land and river components. Numerical experiments have been designed to understand how terrestrial carbon, nitrogen, and phosphorus cycles regulate climate system feedbacks and the sensitivity of the feedbacks to different model treatments, examine key processes governing sediment and biogeochemistry in the rivers and their role in the carbon cycle, and exploring the impacts of human systems in perturbing the hydrological and carbon cycles and their interactions. This presentation will briefly introduce the ACME modeling approaches and discuss preliminary results and insights from numerical experiments that lay the foundation for improving understanding of the integrated climate-biogeochemistry-human system.

Integrated Safety Analysis Teams

NASA Technical Reports Server (NTRS)

Wetherholt, Jonathan C.

2008-01-01

Today's complex systems require understanding beyond one person s capability to comprehend. Each system requires a team to divide the system into understandable subsystems which can then be analyzed with an Integrated Hazard Analysis. The team must have both specific experiences and diversity of experience. Safety experience and system understanding are not always manifested in one individual. Group dynamics make the difference between success and failure as well as the difference between a difficult task and a rewarding experience. There are examples in the news which demonstrate the need to connect the pieces of a system into a complete picture. The Columbia disaster is now a standard example of a low consequence hazard in one part of the system; the External Tank is a catastrophic hazard cause for a companion subsystem, the Space Shuttle Orbiter. The interaction between the hardware, the manufacturing process, the handling, and the operations contributed to the problem. Each of these had analysis performed, but who constituted the team which integrated this analysis together? This paper will explore some of the methods used for dividing up a complex system; and how one integration team has analyzed the parts. How this analysis has been documented in one particular launch space vehicle case will also be discussed.

A biologically inspired neural network model to transformation invariant object recognition

NASA Astrophysics Data System (ADS)

Iftekharuddin, Khan M.; Li, Yaqin; Siddiqui, Faraz

2007-09-01

Transformation invariant image recognition has been an active research area due to its widespread applications in a variety of fields such as military operations, robotics, medical practices, geographic scene analysis, and many others. The primary goal for this research is detection of objects in the presence of image transformations such as changes in resolution, rotation, translation, scale and occlusion. We investigate a biologically-inspired neural network (NN) model for such transformation-invariant object recognition. In a classical training-testing setup for NN, the performance is largely dependent on the range of transformation or orientation involved in training. However, an even more serious dilemma is that there may not be enough training data available for successful learning or even no training data at all. To alleviate this problem, a biologically inspired reinforcement learning (RL) approach is proposed. In this paper, the RL approach is explored for object recognition with different types of transformations such as changes in scale, size, resolution and rotation. The RL is implemented in an adaptive critic design (ACD) framework, which approximates the neuro-dynamic programming of an action network and a critic network, respectively. Two ACD algorithms such as Heuristic Dynamic Programming (HDP) and Dual Heuristic dynamic Programming (DHP) are investigated to obtain transformation invariant object recognition. The two learning algorithms are evaluated statistically using simulated transformations in images as well as with a large-scale UMIST face database with pose variations. In the face database authentication case, the 90° out-of-plane rotation of faces from 20 different subjects in the UMIST database is used. Our simulations show promising results for both designs for transformation-invariant object recognition and authentication of faces. Comparing the two algorithms, DHP outperforms HDP in learning capability, as DHP takes fewer steps to perform a successful recognition task in general. Further, the residual critic error in DHP is generally smaller than that of HDP, and DHP achieves a 100% success rate more frequently than HDP for individual objects/subjects. On the other hand, HDP is more robust than the DHP as far as success rate across the database is concerned when applied in a stochastic and uncertain environment, and the computational time involved in DHP is more.

Extractive Regimes: Toward a Better Understanding of Indonesian Development

ERIC Educational Resources Information Center

Gellert, Paul K.

2010-01-01

This article proposes the concept of an extractive regime to understand Indonesia's developmental trajectory from 1966 to 1998. The concept contributes to world-systems, globalization, and commodity-based approaches to understanding peripheral development. An extractive regime is defined by its reliance on extraction of multiple natural resources…

20 CFR 662.300 - What is the Memorandum of Understanding (MOU)?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false What is the Memorandum of Understanding (MOU)? 662.300 Section 662.300 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF... Memorandum of Understanding for the One-Stop Delivery System § 662.300 What is the Memorandum of...

Ecological Understanding 1: Ways of Experiencing Photosynthesis.

ERIC Educational Resources Information Center

Carlsson, Britta

2002-01-01

Investigates 10 student teachers' understanding of the different ways in which the function of the ecosystem could be experienced. Explores the functional aspects of the ecosystem using a system approach. Concludes that the idea of transformation is crucial to more complex ways of understanding photosynthesis. (Contains 62 references.) (Author/YDS)

A Recursive Theory for the Mathematical Understanding--Some Elements and Implications.

ERIC Educational Resources Information Center

Pirie, Susan; Kieren, Thomas

There has been considerable interest in mathematical understanding. Both those attempting to build, and those questioning the possibility of building intelligent artificial tutoring systems, struggle with the notions of mathematical understanding. The purpose of this essay is to show a transcendently recursive theory of mathematical understanding…

Students' Understanding of Advanced Properties of Java Exceptions

ERIC Educational Resources Information Center

Rashkovits, Rami; Lavy, Ilana

2012-01-01

This study examines how Information Systems Engineering School students on the verge of their graduation understand the mechanism of exception handling. The main contributions of this paper are as follows: we construct a questionnaire aimed at examining students' level of understanding concerning exceptions; we classify and analyse the students'…

Systems Biology Approaches for Understanding Genome Architecture.

PubMed

Sewitz, Sven; Lipkow, Karen

2016-01-01

The linear and three-dimensional arrangement and composition of chromatin in eukaryotic genomes underlies the mechanisms directing gene regulation. Understanding this organization requires the integration of many data types and experimental results. Here we describe the approach of integrating genome-wide protein-DNA binding data to determine chromatin states. To investigate spatial aspects of genome organization, we present a detailed description of how to run stochastic simulations of protein movements within a simulated nucleus in 3D. This systems level approach enables the development of novel questions aimed at understanding the basic mechanisms that regulate genome dynamics.

A Geographic Information Science (GISc) Approach to Characterizing Spatiotemporal Patterns of Terrorist Incidents in Iraq, 2004-2009

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medina, Richard M; Siebeneck, Laura K.; Hepner, George F.

2011-01-01

As terrorism on all scales continues, it is necessary to improve understanding of terrorist and insurgent activities. This article takes a Geographic Information Systems (GIS) approach to advance the understanding of spatial, social, political, and cultural triggers that influence terrorism incidents. Spatial, temporal, and spatiotemporal patterns of terrorist attacks are examined to improve knowledge about terrorist systems of training, planning, and actions. The results of this study aim to provide a foundation for understanding attack patterns and tactics in emerging havens as well as inform the creation and implementation of various counterterrorism measures.

Unified Synthesis Product (USP) Recommendations

NASA Astrophysics Data System (ADS)

Peterson, T. C.

2009-05-01

The USP identifies a number of areas in which inadequate information or understanding hampers our ability to estimate likely future climate change and its impacts. For example, our knowledge of changes in tornadoes, hail, and ice storms is quite limited, making it difficult to know if and how such events have changed as climate has warmed, and how they might change in the future. Research on ecological responses to climate change also is limited, as is our understanding of social responses. The Report identifies the five most important gaps in knowledge and offers some thoughts on how to address those gaps: 1. Expand our understanding of climate change impacts. There is a clear need to increase understanding of how ecosystems, social and economic systems, human health, and the built environment will be affected by climate change in the context of other stresses. This includes ecosystems as well as economic systems, human health, and the built environment. 2. Refine ability to project climate change at local scales. One of the main messages to emerge from the past decade of synthesis and assessments is that while climate change is a global issue, it has a great deal of regional variability. There is an indisputable need to improve understanding of climate system effects at these smaller scales, because these are often the scales of decision-making in society. 3. Expand capacity to provide decision makers and the public with relevant information on climate change and its impacts. The United States has tremendous potential to create more comprehensive measurement, archive, and data-access systems that could provide great benefit to society. 4. Improve understanding of and ability to identify thresholds likely to lead to abrupt changes in the climate system. Paleoclimatic data shows that climate can and has changed quite abruptly when certain thresholds are crossed. Similarly, there is evidence that ecological and human systems can undergo abrupt change when tipping points are reached. 5. Enhance understanding of how society can adapt to climate change in the context of multiple stresses. There is currently limited knowledge about the ability of communities, regions, and sectors to adapt to future climate change. It is essential to improve understanding of how the capacity to adapt to a changing climate might be exercised, and the vulnerabilities to climate change and other environmental stresses that might remain. Results from these efforts would inform future assessments that continue building our understanding of humanity's impacts on climate, and climate's impacts on us. Such assessments will continue to play a role in helping the U.S. respond to changing conditions. A vision for future climate change assessments includes both sustained extensive practitioner and stakeholder involvement, and periodic, targeted, scientifically rigorous reports similar to the CCSP Synthesis and Assessment Products.

Higher education provision using systems thinking approach - case studies

NASA Astrophysics Data System (ADS)

Dhukaram, Anandhi Vivekanandan; Sgouropoulou, Cleo; Feldman, Gerald; Amini, Ardavan

2018-01-01

The purpose of this paper is to highlight the complexities involved in higher education provision and how systems thinking and socio-technical systems (STS) thinking approach can be used to understand the education ecosystem. Systems thinking perspective is provided using two case studies: the development of European Learner Mobility (EuroLM) service and the delivery of Enterprise System Management (ESM) course at the Birmingham City University, UK. The case studies present how systems thinking using STS approaches like applied organisational change and Cognitive Work Analysis can be used to capture a conceptual model of the education system for understanding the interactions and relationships between the people, technology, processes and the organisations. Using systems thinking perspective, EuroLM has developed a set of technical standards addressed to the European systems developers and ESM delivery ensures that students communicate and collaborate.

The Learning Reconstruction of Particle System and Linear Momentum Conservation in Introductory Physics Course

NASA Astrophysics Data System (ADS)

Karim, S.; Saepuzaman, D.; Sriyansyah, S. P.

2016-08-01

This study is initiated by low achievement of prospective teachers in understanding concepts in introductory physics course. In this case, a problem has been identified that students cannot develop their thinking skills required for building physics concepts. Therefore, this study will reconstruct a learning process, emphasizing a physics concept building. The outcome will design physics lesson plans for the concepts of particle system as well as linear momentum conservation. A descriptive analysis method will be used in order to investigate the process of learning reconstruction carried out by students. In this process, the students’ conceptual understanding will be evaluated using essay tests for concepts of particle system and linear momentum conservation. The result shows that the learning reconstruction has successfully supported the students’ understanding of physics concept.

Advances in Solar Heating and Cooling Systems

ERIC Educational Resources Information Center

Ward, Dan S.

1976-01-01

Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

Elementary student and prospective teachers' agri-food system literacy: Understandings of agricultural and science education's goals for learning

NASA Astrophysics Data System (ADS)

Trexler, Cary Jay

1999-09-01

Although rhetoric abounds in the agricultural education literature regarding the public's dearth of agri-food system literacy, problems arise when establishing educational interventions to help ameliorate illiteracy. Researchers do not fully know what individuals understand about the complex agri-food system. Hence, educational programs and curricula may focus on areas where students already possess well developed and scientifically accurate schemata, while ignoring other areas where incompatible or naive understandings persist. Democratic decisions about complex societal and environmental issues, such as trade-offs of our industrial agri-food system, require individuals to possess understandings of complex interrelationships. This exploratory qualitative study determines what two groups---elementary students and prospective elementary school teachers---understand about selected concepts foundational to agri-food system literacy. To ground the study in current national education curricular standards, a synthesis of both agricultural and science education benchmarks was developed. This helped structure interviews with the study's informants: nine elementary students and nine prospective elementary teachers. Analysis of discourse was based upon a conceptual change methodology. Findings showed that informant background and non-school experiences were linked to agri-food system literacy, while formal, in-school learning was not. For elementary students, high socio-economic status, gardening and not living in urban areas were correlates with literacy; the prospective teacher group exhibited similar trends. Informants understood that food came from farms where plants and animals were raised. For the majority, however, farms were described as large gardens. Additionally, informants lacked a clear understanding of the roles soil and fertilizers play in crop production. Further, few spoke of weeds as competitors with crops for growth requirements. Informants understood that agricultural technologies saved time and reduced labor and were concerned with the immediate impact of agricultural pollution. They, however, did not link their food and fiber consumption with resources use or environmental impact. Additionally, half of the prospective teachers did not understand genetics well enough to discuss how humans engineer life. Notable differences were found between teachers and students in 17% of the elementary benchmarks. Differences between the two groups were found in the elementary students' lack of ability to proffer cause-effect relationships, especially in regard to the use of agricultural technologies.

Imitation and action understanding in autistic spectrum disorders: how valid is the hypothesis of a deficit in the mirror neuron system?

PubMed

Hamilton, Antonia F de C; Brindley, Rachel M; Frith, Uta

2007-04-09

The motor mirror neuron system supports imitation and goal understanding in typical adults. Recently, it has been proposed that a deficit in this mirror neuron system might contribute to poor imitation performance in children with autistic spectrum disorders (ASD) and might be a cause of poor social abilities in these children. We aimed to test this hypothesis by examining the performance of 25 children with ASD and 31 typical children of the same verbal mental age on four action representation tasks and a theory of mind battery. Both typical and autistic children had the same tendency to imitate an adult's goals, to imitate in a mirror fashion and to imitate grasps in a motor planning task. Children with ASD showed superior performance on a gesture recognition task. These imitation and gesture recognition tasks all rely on the mirror neuron system in typical adults, but performance was not impaired in children with ASD. In contrast, the ASD group were impaired on the theory of mind tasks. These results provide clear evidence against a general imitation impairment and a global mirror neuron system deficit in children with autism. We suggest this data can best be understood in terms of multiple brain systems for different types of imitation and action understanding, and that the ability to understand and imitate the goals of hand actions is intact in children with ASD.